Title of Invention	TENSIONER
Abstract	To surely prevent a simple-structured, inexpensive stopper from being detached from a case. A tensioner 1 comprises a first shaft member 3 and a second shaft member 4 that are screwed into each other by screw parts 8 and 9, and a spring 5 that energizes and rotates the first shaft member 3 in only one preset direction, with the first shaft member, the second shaft member, and the spring 5 being accommodated in a case 2, and where said tensioner converts the energizing and rotating force of the spring 5 into a drive force for the second shaft member 4 by restraining the rotation of the second shaft member 4. A stopper 15, which is engaged with the first shaft member 3 so as to put the first shaft member 3 into a rotation-restraining condition that resists the energizing and rotating force of the spring 5, can be inserted into the case 2. The stopper 15 has a structure such that it closely contacts the case 2 or the first shaft member 3 so as to generate friction force for preventing the stopper 15 from being detached from the case 2.

Title of Invention

TENSIONER

Abstract

To surely prevent a simple-structured, inexpensive stopper from being detached from a case. A tensioner 1 comprises a first shaft member 3 and a second shaft member 4 that are screwed into each other by screw parts 8 and 9, and a spring 5 that energizes and rotates the first shaft member 3 in only one preset direction, with the first shaft member, the second shaft member, and the spring 5 being accommodated in a case 2, and where said tensioner converts the energizing and rotating force of the spring 5 into a drive force for the second shaft member 4 by restraining the rotation of the second shaft member 4. A stopper 15, which is engaged with the first shaft member 3 so as to put the first shaft member 3 into a rotation-restraining condition that resists the energizing and rotating force of the spring 5, can be inserted into the case 2. The stopper 15 has a structure such that it closely contacts the case 2 or the first shaft member 3 so as to generate friction force for preventing the stopper 15 from being detached from the case 2.

Full Text	FORM 2 THE PATENTS ACT, 1970 (39 of 1970) & THE PATENTS RULES, 2003 COMPLETE SPECIFICATION [See section 10, Rule 13] TENSIONER; NHK SPRING CO., LTD., A CORPORATION ORGANISED AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 10, FUKUURA 3-CHOME, KANAZAWA-KU, YOKOHAMA-SHI, KANAGAWA 236-0004 JAPAN THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED. Field of the Invention The present invention relates to a tensioner that keeps constant the tension of an endless belt or chain. Background Art of the Invention A tensioner pushes, with a predetermined force, for example, a timing chain or a timing belt that is used for the engine of an automobile, and acts to keep the tension constant if the timing chain or timing belt becomes elongated or loosened. Figure 21 shows the condition of a tensioner 100 when mounted to the engine body 200 of an automobile. Lubricating oil (not shown) is filled inside the engine body 200. A pair of cam sprockets 210, 210 and a crank sprocket 220 are arranged inside the engine body 200, and a timing chain 230 is hooked on the sprockets 210, 210 and the crank sprocket 220 in an endless manner. Also, the timing chain 230 slides on a chain guide 240 that is swingably arranged along the movement path of the timing chain 230. The tensioner 100 is equipped with a case 111 that has a flange part 112 that contacts a mounting face 250 that is formed on the engine body 200 and onto which the tensioner 100 is mounted. When a bolt 270 is fastened under the condition that the flange part 112 is in contact with the mounting face 250, the tensioner 100 is secured to the engine body 200. When the tensioner 100 is secured to the engine body 200, the case 111 penetrates through a mounting hole 260, and a drive shaft 120, which projects from the case 111, pushes the timing chain 230 via the chain guide 240, so that tension can be given to the timing chain 230. In the general structure of the tensioner 100, the drive shaft 120 and a rotary shaft 130 (see Figure 22) are accommodated in the case 111 under the condition that the drive shaft 120 and the rotary shaft 130 are screwed together. When the drive shaft 120 moves forward due to rotation of the rotary shaft 130, tension is given to the timing chain 230. The rotary shaft 130 is rotated by the energizing force of a spring 133 that is accommodated in the case 111. In the structure shown in Figure 22, a torsion spring is used as the spring 133. While one end of the spring 133 is locked to the case 111, the other end 133a is inserted into and locked inside the slit 130a of the rotary shaft 130, so that the rotary shaft 130 is energized and rotated. Prior to mounting the tensioner 100 onto the engine body 200, the tensioner 100 stores rotary energizing force that results due to the torsion of the spring 133. The tensioner 100 is mounted to the engine body 200 under a locked condition that maintains this rotary energizing force. After the tensioner 100 is assembled onto the engine body 200, the rotary energizing force of the spring 133 is released from the locked condition, and the rotary shaft 130 rotates. By this rotation, the drive shaft 120 moves forward, so that tension is given as described above. Accordingly, with such a tensioner it is necessary that the rotary energizing force of the spring 133 be maintained under a locked condition during the process of shipping, transporting, and so on of the tensioner — that is, until the tensioner is mounted onto the engine body 200. The locked condition is maintained by restraining the rotation of the rotary shaft 130, which is caused to rotate by the spring 133. For this reason, stoppers 137, 138 are used, as shown in Figure 22. Also, Patent Documents 1 and 2 describe structures using special stopper mechanisms. In Figure 22(a), a planar stopper 137, which has, in an integral manner, a leg part 137a and a locking part 137b, is used. The leg part 137a is inserted from the rear end of the case 111 and is engaged with the slit 130a of the rotary shaft 130. As shown in Figure 23, four engagement grooves 115 are formed on the rear-end face of the case 111 in such a way that one pair of engagement grooves 115 are arranged opposite to each other, and the other pair of engagement grooves 115 also are also arranged opposite to each other, with the two pairs arranged in such a way that if lines were drawn to connect the two engagement grooves 115 of each pair, the two lines would form a cross. The locking part 137b is engaged with a pair of the opposed engagement grooves 115, so that relative rotation of the stopper 137 against the case 111 is locked. By this locking, the leg part 137a stops the rotation of the rotary shaft 130. In Figure 22(b), a locking part 138b, which extends to a leg part 138a, is wide, and an engagement groove 115 is formed on the rear-end face of the case 111 at a position corresponding to the protruding-edge portion of the locking part 138b. After the leg part 138a is inserted from the rear end of the case 111, the locking part 138b is engaged with the engagement groove 115, so that the rotation of the rotary shaft 130 is stopped, as is similar to the arrangement shown in Figure 22(a). In the structures shown in Figure 22, each of the stoppers 137, 138 is engaged with the case 111 by the torque of the spring 133 acting on the rotary shaft 130, and the stoppers 137, 138 are kept attached to the case 111. In contrast to the above-specified condition, where a stopper 137 or 138 is held together with the case 111, when the stopper 137 or 138 is pulled out of the case, the rotary shaft 130 is released from its rotation-restraining condition. The rotary shaft 130 is then rotated by the energizing force of the spring 133, so that the drive shaft moves forward. After the stopper 137 or 138 is pulled out, a seal bolt (not shown) is screwed into the aperture of the case 111 where the stopper 137 or 138 had been inserted, so as to seal that aperture so that oil is prevented from leaking out of the case 111. In the structure described in Patent Document 1, a stopper mechanism is provided on a side face of the case, an aperture is provided in the side face of the case, a seal member is fitted into the aperture, and a pin-like stopper is inserted into the seal member from the outside of the case and is engaged with the rotary shaft. When the stopper is engaged with the rotary shaft, rotation of the rotary shaft is prevented. After the tensioner is mounted onto the engine body, the stopper is pulled out, so that the rotation-restraining condition is terminated, so that the rotary shaft can be rotated by the spring. In the structure described in Patent Document 2, a stopper mechanism is provided on the rear end of the case, with the stopper mechanism comprising a locking part that is provided on the rear end of the drive shaft, a release button that has a locking pawl that takes hold of the locking part so as to stop the forward movement of the drive shaft, and a cam that releases the locking pawl's hold on the locking part when the release button is pushed. After the tensioner is mounted onto the engine body, the release button is pushed so that the cam cancels the locking condition caused by the locking pawl, so that the drive shaft can move forward. [Patent Document 1] Japanese Published Unexamined Patent Application No. H2-278046 [Patent Document 2] Japanese Published Unexamined Patent Application No. H9-79330 Disclosure of the Invention Problems to Be Solved by the Invention In the above-mentioned structures of Patent Documents 1 and 2, a stopper mechanism also seals the case. Therefore, even after the stopper mechanism terminates the rotation- or drive-restraining condition, the stopper mechanism still serves as a sealing member, and therefore it is not necessary to mount a seal bolt onto the case to prevent leakage of oil from the case, which is a convenient feature of the above-mentioned structure. However, it is necessary to provide a special structure for the stopper mechanism, which increases the cost. In contrast, the structure shown in Figure 22 has the merit that the cost is reduced because a simple-structured stopper is used. However, with an engine that has a small displacement of approximately 50 cc, the torque of the spring 133 is small, and therefore the fixing force for holding the stopper 137 or 138 is also small. Therefore, the stopper is easily detached from the case 111 due to vibrations during transportation, and this detachment terminates the rotation-restraining condition of the rotary shaft 130, which causes the inconvenience of the drive shaft accidentally moving forward. To prevent detachment of the stopper, adhesive tape is attached in such a way that the adhesive tape covers the stopper. However, when adhesive tape is used, additional operations, such as attaching and later removing the adhesive tape, become necessary, which causes the problem of less-efficient workability. Also, when packaging the tensioner, it is necessary to pay attention to ensuring that the stopper will not be detached. However, this makes packaging very troublesome, which is a problem. The present invention has been made in view of the above-mentioned problems. One object of the present invention is to provide a tensioner that can surely prevent a stopper from being detached from the case, even when an inexpensive, simple-structured stopper is used. Means for Solving the Problems For achieving the above-mentioned object, a tensioner described in Claim 1 comprises a first shaft member and a second shaft member that are screwed into each other by screw parts, and a spring that rotates and energizes the first shaft member in only one preset direction, with the first shaft member, the second shaft member, and the spring being accommodated in a case, and converts the energizing and rotating force of the spring into the drive force of the second shaft member by restraining the rotation of the second shaft member; with the tensioner being characterized such that a stopper, which is engaged with the first shaft member so as to resist the energizing and rotating force of the spring and to put the first shaft member in a rotation-restraining condition, can be inserted into the case, and such that the stopper has a structure such that the stopper comes into close contact with the case or the first shaft member so as to generate friction force so as to prevent the stopper from being detached from the case. In the invention described in Claim 1, due to the insertion of the stopper in the case, the stopper comes into close contact with the case or the first shaft member, so that friction force is generated. This friction force surely holds the stopper in the case. Accordingly, the stopper is not detached even when vibrations act on the stopper and the case, or even when the torque of the spring is small. The invention according to Claim 2 is the tensioner described in Claim 1, and wherein (1) the case has, as one of its components, a supporting member that supports the rotation of the first shaft member, and (2) the stopper has such a structure that the stopper comes into close contact with the supporting member so as to generate the friction force. In the invention described in Claim 2, because the stopper comes into close contact with the supporting member, which is a component of the case, the stopper is securely held in the case and is not detached from the case. The invention according to Claim 3 is the tensioner described in Claim 1 or 2, and wherein (1) the stopper has (a) a leg portion that is engaged with the first shaft member, and (b) an action part that has a spring property, and (2) when the leg portion and the action part are inserted into the case, the action part is elastically deformed, so that the action parts come into close contact with the case or the first shaft member. In the invention described in Claim 3, when the action part is inserted into the case and is elastically deformed, the action part comes into close contact with the case or the first shaft member, so that the stopper is securely held in the case and is not detached from the case. Here, the leg portion puts the first shaft member in a rotation-restraining condition. The invention according to Claim 4 is the tensioner described in any one of Claims 1 through 3, and wherein (1) an aperture for mounting a seal bolt is formed in the case, and (2) the stopper is inserted into the case via the aperture. In the invention described in Claim 4, because the stopper can be inserted into the case via the aperture for mounting the seal bolt, the aperture can be used for both mounting the seal bolt and inserting the stopper. Effects of the Invention With the present invention, when the stopper is inserted into the case, the stopper comes into close contact with the case or the first shaft member so as to generate friction force, so that the stopper is securely held in the case. Therefore, even when vibrations act on the stopper and the case, or even when the torque of the spring is small, the stopper is not accidentally detached from the case. Also, because the stopper has a simple structure, an inexpensive tensioner can be provided. Brief Descriptions of the Drawings Figure 1 is a cross-sectional view showing the situation when the stopper is inserted into the first embodiment of the present invention. Figure 2 is a plan view of the first embodiment. Figure 3 is a cross-sectional view of the first embodiment. Figure 4 consists of a side view (4a) and a front view (4b) of the stopper used in the first embodiment. Figure 5 is a perspective view showing the situation when the stopper is inserted into the case. Figure 6 consists of a front view (6a )and a side view (6b) of the stopper used in the second embodiment. Figure 7 is a cross-sectional view showing the situation when the stopper is inserted into the second embodiment. Figure 8 consists of a side view (8a) and a front view (8b) of the stopper used in the third embodiment. Figure 9 is a cross-sectional view showing the situation when the stopper is inserted into the third embodiment. Figure 10 consists of a front view (10a) and a side view(l0b) of the stopper used in the fourth embodiment. Figure 11 is a cross-sectional view showing the situation when the stopper is inserted into the fourth embodiment. Figure 12 consists of a front view (12a) and a side view (12b) of the stopper used in a variation of the fourth embodiment. Figure 13 is a cross-sectional view showing the situation when the stopper is inserted into a variation of the fourth embodiment. Figure 14 is a cross-sectional view showing the first variation of the fifth embodiment. Figure 15 is a cross-sectional view showing the second variation of the fifth embodiment. Figure 16 consists of a cross-sectional view of the aperture 18 (16a) and a cross-sectional view of the stopper 15 (16b) showing the third variation of the fifth embodiment. Figure 17 is a cross-sectional view showing the fourth variation of the fifth embodiment. Figure 18 consists of a front view (18a), and a plan view (18b), and a side view (18c) showing the first variation of the sixth embodiment. Figure 19 consists of a front view (19a), a plan view (19b) a side view (19c) showing the second variation of the sixth embodiment. Figure 20 consists of a front view (20a), a plan view (20b), and a side view (20c) showing the third variation of the sixth embodiment. Figure 21 is a partial side view showing the situation when the tensioner is mounted to an engine body. Figures 22(a) and (b) are cross-sectional views showing conventional examples when variations of the stopper have been inserted into the case. Figure 23 is a perspective view showing the situation when the stopper of Figure 22(a) is engaged. Explanation of Numbers Used in the Drawings 1 tensioner 2 case 3 first shaft member 4 second shaft member 5 spring 6 bearing 8 male screw 9 female screw 15 stopper 15a leg part 15 b locking part 15 c action part 18 aperture 19 engagement groove Best Modes for Carrying Out the Invention The present invention will now be described in detail with reference to the embodiments illustrated in the drawings. For each embodiment, identical numbers are used to refer to identical members. (First Embodiment) Figures 1 through 5 show a tensioner 1 in a first embodiment of the present invention. Figure 1 is a cross-sectional view showing that a stopper is inserted. Figure 2 is a plan view of the tensioner 1. Figure 3 is a cross-sectional view of the entire tensioner 1. . Figure 4 is a side view and a plan view of the stopper. Figure 5 is a perspective view showing that the stopper is inserted. As shown in Figures 2 and 3, a tensioner 1 comprises a case 2, a first shaft member 3, a second shaft member 4, and a spring 5. The case 2 has (1) a shell part 2a, (2) a flange part 2b that extends outside from the circumference of the shell part 2a, and (3) an accommodation hole 2c that accommodates the first shaft member 3 and is formed in the shell part 2a in the axial direction (driving direction). The axial-tip portion of the accommodation hole 2c is open, and the first shaft member 3, the second shaft member 4, and the spring 5 are accommodated in the accommodation hole 2c. The flange 2b is for mounting the tensioner 1 onto an engine body, and a mounting hole 2d, through which penetrates a mounting bolt (not shown) that is to be screwed to the engine body, is formed in the flange part 2b. The first shaft member 3 and the second shaft member 4 are inserted into the accommodation hole 2c of the case 2 under the condition that the first shaft member 3 and the second shaft member 4 are screwed together. The first shaft member 3 is energized by the spring 5 and rotates, and the second shaft member 4 moves forward in the axial direction of the case 2 from the case 2 due to rotation of the first shaft member 3. In the first shaft member 3, a shaft part 3 a on the base-end side and a screw shaft part 3b on the tip-end side are integrally formed to extend in the axial direction of the tensioner 1 and a male screw 8 is formed on the outer periphery of the screw shaft part 3b. The second shaft member 4 is formed into a cylindrical shape, and is screwed to the shaft part 3 a of the first shaft member 3. Accordingly, a female screw 9 that is to be screwed with the male screw 8 is formed on the inner face of the second shaft member 4. A bearing 6 is secured to the tip portion of the case 2 by a snap ring 13. The bearing 6 is slidably penetrated by the second shaft member 4 and restrains the rotation of the second shaft member 4. Accordingly, a slide hole 6a, through which the second shaft member 4 penetrates, is formed in the bearing 6. The inner face of the slide hole 6a and the outer face of the second shaft member 4 are formed to have a cross-section of an approximately oval shape, a D-cut shape, a parallel-cut shape, or other non-circular shape, so that the bearing 6 restrains the rotation of the second shaft member 4. A cap 10 is secured to the tip portion of the second shaft member 4. In Figure 3, a portion of the first shaft member 3 where the first shaft member 3 and the second shaft member 4 are screwed together is inserted inside a cylindrical spacer 7. The spacer 7 faces the bearing 6 that is fixed to the tip portion of the case 2, and the bearing 6 prevents the spacer 7 from being detached from the case 2. A flange part 3c that has a large diameter is formed at the boundary portion between the shaft part 3 a and the screw shaft part 3b of the first shaft member 3, and the flange part 3c contacts the spacer 7. This prevents the first shaft member 3 and the second shaft member 4 from being detached from the case 2. A torsion spring is used as a spring 5 that energizes and rotates the first shaft member 3, which penetrates through a coil part of the spring 5. One end 5a of the spring 5 is locked to the case 2, and the other end 5b is locked to the first shaft member 3. Accordingly, when the spring 5 is twisted so as to give a predetermined torque, the first shaft member 3 rotates in the only direction in which it is preset to rotate, and under no condition rotates in the reverse rotation. The rotation force of the first shaft member 3 is transmitted to the second shaft member 4. However, as described above, because the rotation of the second shaft member 4 is restrained by the bearing 6, the rotation force is converted into a drive force, so that the second shaft member 4 does not rotate but instead moves forward in a linear direction from the case 2. This forward movement can give tension to a chain in the engine body. In order that the other end 5b of the spring 5 is engaged with the first shaft member 3, a slit 12 is formed on the base-end face of the shaft part 3a of the first shaft member 3. The slit 12 is formed so as to extend in the axial direction of the first shaft member 3 from the center portion of the base-end face of the shaft part 3 a. When the other end 5b of the spring 5 is inserted into the slit 12, the other end 5b is engaged with the first shaft member 3. As described below, a leg part 15a of a stopper 15 is inserted into and engaged with the slit 12. The rotation of the first shaft member 3 is supported both by the case 2 and by a supporting member that is arranged in the case 2. In Figure 3, a swivel plate 17 is installed in the case 2 as a supporting member. The swivel plate 17 is press-fitted to the base-end side of the accommodation hole 2c of the case 2 and is integrated with the case 2, so that the swivel plate 17, as a supporting member, is a component of the case 2. The inner face of the swivel plate 17 supports both the base-end face and side-face portion of the first shaft member 3 — with said side-face portion extending up from said base-end face — so that the swivel plate 17 supports the rotation of the first shaft member 3. An aperture 18 that is connected with the accommodation hole 2c is formed in the axial direction of the first shaft member 3 on the base-end side of the case 2. After the below-described stopper 15 is pulled out of the aperture 18, a seal bolt (not shown) is mounted into the aperture 18 by screwing or press-fitting, and the mounted seal bolt seals the case 2 so as to prevent oil from leaking from the case 2. Because the aperture 18 can be used for both mounting the seal bolt and inserting the stopper, the structure of the lower portion of the case 2 shown in Figure 3 can be made simple. An engagement groove 19 is formed on the base-end face of the case 2 and is engaged with the stopper 15. In this embodiment, the first shaft member 3 is put under a rotation-restraining condition by the stopper 15, and the stopper 15 is inserted through the aperture 18 of the case 2 and engaged with the first shaft member 3. As shown in Figure 4, the stopper 15 has a leg part 15a, and a wide, locking part 15b that is integrally formed on the base-end side of the leg part 15a. The leg part 15a is inserted into the slit 12 of the first shaft member 3, and is engaged with the first shaft member 3. The locking part 15b is engaged with the engagement groove 19 that is formed on the base-end face of the case 2. As shown in Figure 5, four engagement grooves 19 are formed on the base-end face of the case 2 in such a way that one pair of the engagement grooves 19 are arranged opposite to each other, and the other pair of the engagement grooves 19 also are also arranged opposite to each other, with the two pairs arranged in such a way that if lines were drawn to connect the two engagement grooves 19 of each pair, the two lines would form a cross. When the locking part 15b is engaged with the engagement grooves 19, and the leg part 15a is engaged with the slit 12, the stopper 15 acts to prevent the rotation of the first shaft member 3 that otherwise would result due to the energizing and rotating force of the spring 5. In addition, right and left action parts 15c are formed on the stopper 15 integrally with the leg part 15a and the locking part 15b. The right and left action parts 15c extend up from both faces of the locking part 15b in the direction of the leg part 15 a. The action parts 15c extend up from the both side faces of the locking part 15b, and gradually move away from the leg part 15a, so that tip portions of the action parts 15c are free ends. The right and left action parts 15 c have a spring force that is an elastic force that pushes the leg part 15a upward (upward as in Figure 4). The action parts 15c, the leg part 15a, and the locking part 15b can be integrally formed by molding, such as by injection molding using resin or rubber, or by press molding using metals. Also, the action parts 15c, the leg part 15a, and the locking part 15b can be formed using different members or different materials and then be integrated together to be used as the stopper 15. As shown in Figure 1, in this embodiment, under a free condition before the stopper 15 is inserted into the aperture 18 of the case 2, the maximum interval distance Z between the right and left action parts 15c is set larger than the diameter of the aperture 18. Accordingly, when the stopper 15 is inserted into the aperture 18, the right and left action parts 15c are elastically deformed so as to approach each other and to closely contact the inner face of the aperture 18. In this manner, when the action parts 15c closely contact the inner face of the aperture 18, friction force is generated between the action parts 15c and the aperture 18, so that the stopper 15 is securely held by the case 2, and is not detached from the case 2. The actions of this embodiment will now be described in reference to Figures 1 and 5. The first shaft member 3, the second shaft member 4 — which are under the condition that the first shaft member 3 and the second shaft member 4 are screwed together — and the spring 5 are assembled together, and inserted into the case 2. Then, the spring 5 is twisted, so that torque for energizing and rotating the first shaft member 3 is stored. Then, immediately after this twisting, the stopper 15 is inserted into the aperture 18 of the case 2. The stopper 15 is inserted into the aperture 18 of the case 2 under a free condition such that the right and left action parts 15c are separated from each other at their maximum interval distance Z. The stopper 15 is inserted into the aperture 18 from the leg part 15a as a leading end, that is, from the free-end side of the action parts 15c. The leg part 15a, by being inserted into the aperture 18, is inserted into and engages with the slit 12 of the first shaft member 3. Also, the locking part 15b is inserted into and engaged with the engagement groove 19 on the base-end face of the case 2. In this manner, when the leg part 15a is engaged with the slit 12 and the locking part 15b is engaged with the engagement groove 19, the first shaft member 3 is put under a rotation-restraining condition. In this case, before the leg part 15a is engaged with the first shaft member 3 and the locking part 15b is inserted into the engagement groove 19, the stopper 15 can be rotated. By doing do, the first shaft member 3 is rotated, and the spring 5 is twisted. When the stopper 15 is inserted into the aperture 18 of the case 2 as described above, the right and left action parts 15c of the stopper 15 are elastically deformed and closely contact the inner face of the aperture 18, as a result of which the action parts 15c generate a reaction force F against the case 2. Also, because the right and left action parts 15c closely contact the inner face of the aperture 18, a fixing force R, the size of which varies depending on the friction coefficient \x for the close contacting area, is generated in the axial direction of the first shaft member 3. The fixing force R satisfies the formula, R = F,. The larger the reaction force F and the apparent friction coefficient \x, the larger the fixing force R. In this embodiment, because the friction force — generated by close contact of the action parts 15c — holds the stopper 15 so that it is not detached from the aperture 18, the stopper 15 can be securely held in the case 2. Therefore, even when vibrations occur during transportation, the stopper 15 does not move in the axial direction of the first shaft member 3. Even when the torque of the spring 5 is low, the stopper 15 is prevented from being detached from the case 2. In this embodiment, because the stopper 15 is not detached from the case 2, a special measure for preventing detachment of the stopper 15 is not required. Also, detachment of the stopper 15 is prevented by the friction force that is generated due to the close contact of the action parts 15c with the aperture 18 of the case 2. The magnitude of this friction force can be set freely, irrespective of the torque of the spring 5, and therefore design flexibility is enhanced. Furthermore, because the stopper 15 can have a simple structure and be integrally formed using a single material, it can be provided at low cost. (Second Embodiment) Figures 6 and 7 show a second embodiment of the present invention. As shown in Figure 6, the stopper 15 of this embodiment is molded into a co-shape as seen from the front. The leg part 15a is positioned in the center, and the action parts 15c are positioned on both sides of the leg part 15a. The leg part 15a and the action parts 15c are integrally formed using a material such as resin or rubber. The action parts 15c extend from the base end of the leg part 15a in the sideways direction under a curving condition, and extend up more or less parallel to the leg part 15a. The tip portions of the action parts 15c are free ends. The right and left action parts 15c are bent toward the leg part 15a in a manner such that the free ends of the action parts 15c approach the leg part 15a. Thus, a spring property, capable of elastic deformation, is given to the action parts 15c. Furthermore, on the free-end sides of the right and left action parts 15c, protruding portions 15d that protrude toward the leg part 15a are formed on faces opposite the leg part 15a. The protrusion portions 15d closely contact the case 2 and, due to this close contact, friction force is generated on the action parts 15c. In this embodiment, the right and left action parts 15c also serve as locking parts to be engaged with the case 2. Figure 7 shows the situation when the stopper 15 is mounted to the case 2 in this embodiment. Engagement grooves 21, which are different from the engagement grooves 19 at the center portion, are formed on the outer peripheral sides of the base end of the case 2. The leg part 15a of the stopper 15 is inserted into the aperture 18 of the case 2, and the tip portion of the leg part 15a is inserted and locked in the slit 12 of the first shaft member 3. Therefore, when the stopper 15 is rotated in a way similar to that described above (in Paragraph [0042]), the spring 5 can be twisted and fastened via the first shaft member 3. Furthermore, when the stopper 15 is made to approach the case 2, the right and left action parts 15c are inserted into and engaged with the engagement grooves 21, and because the protrusion parts 15d of the action parts 15c closely contact the sidewall portions of the case 2, friction force is generated on those portions. The stopper 15 is securely held in the case 2 by this friction force, so as to prevent detachment of the stopper 15. (Third Embodiment) Figures 8 and 9 show a third embodiment of the present invention. As shown in Figure 8, in the stopper 15 of this embodiment, right and left action parts 15c are formed at the leg part 15a. The right and left action parts 15c are integrally formed so as to incline and expand in the sideways direction of the tip of the leg part 15 a. This inclination gives to the action parts 15c a spring property, making them capable of elastic deformation. The maximum interval distance Z between the right and left action parts 15c is set larger than the width of the slit 12 of the first shaft member 3. Also, a wide locking part 15b is integrally formed on the base end of the leg part 15a. In this embodiment also, the stopper 15 is integrally formed using a single material, such as resin, rubber, or metal. Each of the parts, including the action parts 15c, is not to be limited to the above materials, and each can be formed of a different material, and then the parts can be assembled together integrally. As shown in Figure 9, when the stopper 15 of this embodiment is inserted into the case 2 from the aperture 18, the leg part 15a and the action parts 15c are integrally inserted into the slit 12 of the first shaft member 3. In this insertion, the right and left action parts 15c are elastically deformed in a manner such that the distance between the right and left action parts 15c becomes small. Therefore, the action parts 15c closely contact the inner face of the slit 12 of the first shaft member 3 so as to generate friction force. The action parts 15c are prevented from being detached from the case 2, and thus the stopper 15 is prevented from being detached from the case 2. In the initial phase of inserting the locking part 15b into the aperture 18, the locking part 15b is not yet engaged with the engagement grooves 19 of the case 2, and therefore it is possible to rotate the stopper 15 so that the first shaft member 3 is rotated and the spring 5 is twisted and fastened. Then, by inserting the stopper 15 further, the locking part 15b is engaged with the engagement grooves 19, and as a result the first shaft member 3 is put under a rotation-restraining condition. In this embodiment also, the detachment of the stopper 15 can be surely prevented by the action parts 15c. [0054] (Fourth Embodiment) Figures 10 and 11 show a fourth embodiment of the present invention. As shown in Figure 10, the stopper 15 of this embodiment is formed somewhat like a U-shape, and its free-end sides are right and left action parts 15c that also serve as leg parts 15a. As shown in Figure 11, the right and left action parts 15c are inserted into the slit 12 of the first shaft member 3, and the maximum interval distance Z between the right and left action parts 15c under a free condition before insertion into the slit 12 is set larger than the diameter of the opening 17a of a swivel plate 17. Also, tapered parts 15e that taper toward the tip ends of the right and left action parts 15c are formed at the tip portions of the right and left action parts 15c. Furthermore, locking parts 15b, which expand outward in a stepped manner, are formed at the base ends of the right and left action parts 15c. In this embodiment, when the stopper 15 is inserted into the case 2 through the aperture 18, the tapered faces 15e at the tip portions contact the swivel plate 17, so that the action parts 15c are elastically deformed — in a manner so as to reduce the distance between the right and left action parts 15c — and pass through the swivel plate 17. By elastic deformation of the right and left action parts 15c, the outer faces of the action parts closely contact the inner face of the swivel plate 17 and generate friction force that prevents the stopper 15 from being detached from the case 2. Here, the locking parts 15b are engaged with the engagement grooves 19 of the case 2, so that the stopper 15 can put the first shaft member 3 into a rotation-restraining condition. Figures 12 and 13 show a variation of this embodiment. In this variation, protrusion portions 15 f that prevent the stopper 15 from coming off of the swivel plate 17 are formed outside on the free-end sides of the U-shaped stopper 15. Also in this variation, the right and left action parts 15c closely contact the inner face of the swivel plate 17 so as to generate friction force, so that the stopper 15 can be surely prevented from being detached from the case 2. In addition, in this variation, the protrusion portions 15f are formed on the right and left action parts 15 c, and therefore the fixing force against the swivel plate 17 becomes large, and thus detachment of the stopper 15 can be prevented more surely. (Fifth Embodiment) Figures 14 to 17 show a fifth embodiment of the present invention. In this embodiment, another relationship between the aperture 18 of the case 2 and the stopper 15 is shown. The stopper 15 has a leg part 15a that is inserted into the slit 12 of the first shaft member 3, a locking part 15b that is engaged with the engagement grooves 19 of the case 2, and right and left elastically-deformable action parts 15 c that have a spring property similar to that of the action parts 15c of the first embodiment. In a first variation of the fifth embodiment shown in Figure 14, the aperture 18 of the case 2 has a conical shape. The conical aperture 18 is a conical hole that has a gradient 9 and a diameter that is gradually reduced toward the first shaft member 3. In a second variation of the fifth embodiment shown in Figure 15, the inner face of the aperture 18 is made to have projections and indentations like a casting surface. In these embodiments, when the stopper 15 is inserted into the aperture 18, the action parts 15c rigidly closely contact the inside surface of the aperture 18, so that a large friction force is generated. Accordingly, detachment of the stopper 15 from the case 2 can be prevented more surely. In the above-mentioned embodiments, there is no need to specially process the action parts 15c of the stopper 15, or for them to have a special shape. Therefore, the stopper 15 can easily be manufactured at low cost. Also, wrinkling or multithread processing can be applied to the portion of the aperture 18 that contacts the action parts 15c of the stopper 15, or the aperture 18 can be formed into an inverted conical shape, which is opposite to that in Figure 14. Thus, the friction force against the stopper 15 can be made large, so that the stopper 15 can be stably held in the case 2. In third and fourth variations of the fifth embodiments shown in Figures 16 and 17, a screw 21 is formed on the inner face of the aperture 18. By forming the screw 21, a seal bolt can be screwed together with the aperture 18 after the stopper 15 is pulled out, so that oil can be prevented from leaking from the case 2. In Figure 16, when the action parts 15c of the stopper 15 contact the threads of the screw 21, friction force is generated. That is to say, the flat portions of the action parts 15c closely contact the screw 21, and therefore the screw 21 is not damaged at the time that the stopper 15 is pulled out from the case 2, which is a merit of the present invention. In Figure 17, projections and indentations 15g — which correspond to those of the screw 21 — are formed on the right and left action parts 15c of the stopper 15, and these projections and indentations 15g are fitted with the screw 21. Under such a fitting condition, because the action parts 15c rigidly closely contact the inside surface of the aperture 18, the stopper 15 can be fixed to the case 2 more stably. (Sixth Embodiment) Figures 18 through 20 show a sixth embodiment of the present invention. This embodiment includes variations of the action parts 15c of the stopper 15. In a first variation of the sixth embodiment shown in Figure 18, the portions of the right and left action parts 15c that contact the case 2, are formed like an arc. An arc-like face 15i is formed so as to extend in the direction in which the stopper 15 is inserted into the case 2. Therefore, the stopper can rigidly closely contact the inside surface of the aperture 18 of the case 2. In a second variation of the sixth embodiment shown in Figure 19, the arc-like faces 15i of the right and left action parts 15c are formed shorter than those in the embodiment shown in Figure 18. In this case also, the stopper can rigidly closely contact the inside surface of the aperture 18 of the case 2. In a third variation of the sixth embodiment shown in Figure 20, projections 15k are formed on the right and left action parts 15c. The projections 15k are formed so has to have inverted shapes so as to project in the direction opposite to the direction in which the stopper 15 is inserted into the aperture 18 of the case 2. By having such an inverted shape, the action parts 15c can rigidly closely contact the inside surface of the aperture 18, so that the stopper 15 can be rigidly held by the case 2. The present invention is not limited to the above-mentioned embodiments, and it can be changed in various ways. For example, the action parts 15c, which closely contact the case 2 or the swivel plate 17, can be formed into various shapes other than those in the above-described embodiments, and the positions at which the action parts 15c are arranged on the stopper 15 can be changed appropriately. Also, a spring other than a torsion spring, such as a spiral spring, can be used as the spring for energizing and rotating the first shaft member 3. Industrial Applicability Because the stopper is not detached from the case due to factors such as vibrations during transportation, the present invention can be effectively applied as a tensioner for a belt or chain that is used for a vehicle. WE CLAIM 1. A tensioner that comprises a first shaft member and a second shaft member that are screwed into each other by screw parts, and a spring that rotates and energizes the first shaft member in only one preset direction, with the first shaft member, the second shaft member, and the spring being accommodated in a case, and that converts the energizing and rotating force of the spring into a drive force for the second shaft member by restraining the rotation of the second shaft member; and wherein a stopper can be inserted into the case so as to engage with the first shaft member so as to resist the energizing and rotating force of the spring and to put the first shaft member in a rotation-restraining condition, and wherein the stopper has a structure such that it closely contacts the case or the first shaft member so as to generate friction force that prevents the stopper from getting detached from the case. 2. The tensioner described in Claim 1, and wherein said case has a supporting member that supports the rotation of the first shaft member as a component, and wherein said stopper has a structure so that it closely contacts the supporting member so as to generate said friction force. 3. The tensioner described in Claim 1 or 2, and wherein the stopper has a leg portion that is engaged with the first shaft member, and action parts that have a spring property, and wherein when the leg portion and the action parts are inserted into the case, the action part is elastically deformed, so that the action parts come into close contact with the case or the first shaft member. 4. The tensioner described in any of Claims 1 to 3, and wherein an aperture for mounting a seal bolt is formed in said case, and wherein said stopper is inserted into the case via said aperture. ABSTRACT To surely prevent a simple-structured, inexpensive stopper from being detached from a case. A tensioner 1 comprises a first shaft member 3 and a second shaft member 4 that are screwed into each other by screw parts 8 and 9, and a spring 5 that energizes and rotates the first shaft member 3 in only one preset direction, with the first shaft member, the second shaft member, and the spring 5 being accommodated in a case 2, and where said tensioner converts the energizing and rotating force of the spring 5 into a drive force for the second shaft member 4 by restraining the rotation of the second shaft member 4. A stopper 15, which is engaged with the first shaft member 3 so as to put the first shaft member 3 into a rotation-restraining condition that resists the energizing and rotating force of the spring 5, can be inserted into the case 2. The stopper 15 has a structure such that it closely contacts the case 2 or the first shaft member 3 so as to generate friction force for preventing the stopper 15 from being detached from the case 2.

Full Text

FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]
TENSIONER;
NHK SPRING CO., LTD., A CORPORATION ORGANISED AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 10, FUKUURA 3-CHOME, KANAZAWA-KU, YOKOHAMA-SHI, KANAGAWA 236-0004 JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

Field of the Invention
The present invention relates to a tensioner that keeps constant the tension of an endless belt or chain. Background Art of the Invention
A tensioner pushes, with a predetermined force, for example, a timing chain or a timing belt that is used for the engine of an automobile, and acts to keep the tension constant if the timing chain or timing belt becomes elongated or loosened.
Figure 21 shows the condition of a tensioner 100 when mounted to the engine body 200 of an automobile. Lubricating oil (not shown) is filled inside the engine body 200. A pair of cam sprockets 210, 210 and a crank sprocket 220 are arranged inside the engine body 200, and a timing chain 230 is hooked on the sprockets 210, 210 and the crank sprocket 220 in an endless manner. Also, the timing chain 230 slides on a chain guide 240 that is swingably arranged along the movement path of the timing chain 230.
The tensioner 100 is equipped with a case 111 that has a flange part 112 that contacts a mounting face 250 that is formed on the engine body 200 and onto which the tensioner 100 is mounted. When a bolt 270 is fastened under the condition that the flange part 112 is in contact with the mounting face 250, the tensioner 100 is secured to the engine body 200. When the tensioner 100 is secured to the engine body 200, the case 111 penetrates through a mounting hole 260, and a drive shaft 120, which projects from the case 111, pushes the timing chain 230 via the chain guide 240, so that tension can be given to the timing chain 230.
In the general structure of the tensioner 100, the drive shaft 120 and a rotary shaft 130 (see Figure 22) are accommodated in the case 111 under the condition that the drive shaft 120 and the rotary shaft 130 are screwed together. When the drive shaft 120

moves forward due to rotation of the rotary shaft 130, tension is given to the timing chain 230.
The rotary shaft 130 is rotated by the energizing force of a spring 133 that is accommodated in the case 111. In the structure shown in Figure 22, a torsion spring is used as the spring 133. While one end of the spring 133 is locked to the case 111, the other end 133a is inserted into and locked inside the slit 130a of the rotary shaft 130, so that the rotary shaft 130 is energized and rotated.
Prior to mounting the tensioner 100 onto the engine body 200, the tensioner 100 stores rotary energizing force that results due to the torsion of the spring 133. The tensioner 100 is mounted to the engine body 200 under a locked condition that maintains this rotary energizing force. After the tensioner 100 is assembled onto the engine body 200, the rotary energizing force of the spring 133 is released from the locked condition, and the rotary shaft 130 rotates. By this rotation, the drive shaft 120 moves forward, so that tension is given as described above. Accordingly, with such a tensioner it is necessary that the rotary energizing force of the spring 133 be maintained under a locked condition during the process of shipping, transporting, and so on of the tensioner — that is, until the tensioner is mounted onto the engine body 200. The locked condition is maintained by restraining the rotation of the rotary shaft 130, which is caused to rotate by the spring 133. For this reason, stoppers 137, 138 are used, as shown in Figure 22.
Also, Patent Documents 1 and 2 describe structures using special stopper mechanisms.
In Figure 22(a), a planar stopper 137, which has, in an integral manner, a leg part 137a and a locking part 137b, is used. The leg part 137a is inserted from the rear end of the case 111 and is engaged with the slit 130a of the rotary shaft 130. As shown in Figure 23, four engagement grooves 115 are formed on the rear-end face of the case 111 in such

a way that one pair of engagement grooves 115 are arranged opposite to each other, and the other pair of engagement grooves 115 also are also arranged opposite to each other, with the two pairs arranged in such a way that if lines were drawn to connect the two engagement grooves 115 of each pair, the two lines would form a cross. The locking part 137b is engaged with a pair of the opposed engagement grooves 115, so that relative rotation of the stopper 137 against the case 111 is locked. By this locking, the leg part 137a stops the rotation of the rotary shaft 130.
In Figure 22(b), a locking part 138b, which extends to a leg part 138a, is wide, and an engagement groove 115 is formed on the rear-end face of the case 111 at a position corresponding to the protruding-edge portion of the locking part 138b. After the leg part 138a is inserted from the rear end of the case 111, the locking part 138b is engaged with the engagement groove 115, so that the rotation of the rotary shaft 130 is stopped, as is similar to the arrangement shown in Figure 22(a).
In the structures shown in Figure 22, each of the stoppers 137, 138 is engaged with the case 111 by the torque of the spring 133 acting on the rotary shaft 130, and the stoppers 137, 138 are kept attached to the case 111. In contrast to the above-specified condition, where a stopper 137 or 138 is held together with the case 111, when the stopper 137 or 138 is pulled out of the case, the rotary shaft 130 is released from its rotation-restraining condition. The rotary shaft 130 is then rotated by the energizing force of the spring 133, so that the drive shaft moves forward. After the stopper 137 or 138 is pulled out, a seal bolt (not shown) is screwed into the aperture of the case 111 where the stopper 137 or 138 had been inserted, so as to seal that aperture so that oil is prevented from leaking out of the case 111.
In the structure described in Patent Document 1, a stopper mechanism is provided on a side face of the case, an aperture is provided in the side face of the case, a

seal member is fitted into the aperture, and a pin-like stopper is inserted into the seal member from the outside of the case and is engaged with the rotary shaft. When the stopper is engaged with the rotary shaft, rotation of the rotary shaft is prevented. After the tensioner is mounted onto the engine body, the stopper is pulled out, so that the rotation-restraining condition is terminated, so that the rotary shaft can be rotated by the spring.
In the structure described in Patent Document 2, a stopper mechanism is provided on the rear end of the case, with the stopper mechanism comprising
a locking part that is provided on the rear end of the drive shaft,
a release button that has a locking pawl that takes hold of the locking part so as to stop the forward movement of the drive shaft, and
a cam that releases the locking pawl's hold on the locking part when the release button is pushed.
After the tensioner is mounted onto the engine body, the release button is pushed so that the cam cancels the locking condition caused by the locking pawl, so that the drive shaft can move forward.
[Patent Document 1] Japanese Published Unexamined Patent Application No. H2-278046
[Patent Document 2] Japanese Published Unexamined Patent Application No. H9-79330 Disclosure of the Invention Problems to Be Solved by the Invention
In the above-mentioned structures of Patent Documents 1 and 2, a stopper mechanism also seals the case. Therefore, even after the stopper mechanism terminates the rotation- or drive-restraining condition, the stopper mechanism still serves as a sealing member, and therefore it is not necessary to mount a seal bolt onto the case to

prevent leakage of oil from the case, which is a convenient feature of the above-mentioned structure. However, it is necessary to provide a special structure for the stopper mechanism, which increases the cost.
In contrast, the structure shown in Figure 22 has the merit that the cost is reduced because a simple-structured stopper is used. However, with an engine that has a small displacement of approximately 50 cc, the torque of the spring 133 is small, and therefore the fixing force for holding the stopper 137 or 138 is also small. Therefore, the stopper is easily detached from the case 111 due to vibrations during transportation, and this detachment terminates the rotation-restraining condition of the rotary shaft 130, which causes the inconvenience of the drive shaft accidentally moving forward.
To prevent detachment of the stopper, adhesive tape is attached in such a way that the adhesive tape covers the stopper. However, when adhesive tape is used, additional operations, such as attaching and later removing the adhesive tape, become necessary, which causes the problem of less-efficient workability. Also, when packaging the tensioner, it is necessary to pay attention to ensuring that the stopper will not be detached. However, this makes packaging very troublesome, which is a problem.
The present invention has been made in view of the above-mentioned problems. One object of the present invention is to provide a tensioner that can surely prevent a stopper from being detached from the case, even when an inexpensive, simple-structured stopper is used. Means for Solving the Problems
For achieving the above-mentioned object, a tensioner described in Claim 1 comprises
a first shaft member and a second shaft member that are screwed into each other by screw parts, and

a spring that rotates and energizes the first shaft member in only one preset direction,
with the first shaft member, the second shaft member, and the spring being accommodated in a case,
and converts the energizing and rotating force of the spring into the drive force of the second shaft member by restraining the rotation of the second shaft member; with the tensioner being characterized such that
a stopper, which is engaged with the first shaft member so as to resist the energizing and rotating force of the spring and to put the first shaft member in a rotation-restraining condition, can be inserted into the case, and such that
the stopper has a structure such that the stopper comes into close contact with the case or the first shaft member so as to generate friction force so as to prevent the stopper from being detached from the case.
In the invention described in Claim 1, due to the insertion of the stopper in the case, the stopper comes into close contact with the case or the first shaft member, so that friction force is generated. This friction force surely holds the stopper in the case. Accordingly, the stopper is not detached even when vibrations act on the stopper and the case, or even when the torque of the spring is small.
The invention according to Claim 2 is the tensioner described in Claim 1, and wherein (1) the case has, as one of its components, a supporting member that supports the rotation of the first shaft member, and (2) the stopper has such a structure that the stopper comes into close contact with the supporting member so as to generate the friction force. In the invention described in Claim 2, because the stopper comes into close contact with the supporting member, which is a component of the case, the stopper is securely held in the case and is not detached from the case.

The invention according to Claim 3 is the tensioner described in Claim 1 or 2, and wherein (1) the stopper has (a) a leg portion that is engaged with the first shaft member, and (b) an action part that has a spring property, and (2) when the leg portion and the action part are inserted into the case, the action part is elastically deformed, so that the action parts come into close contact with the case or the first shaft member.
In the invention described in Claim 3, when the action part is inserted into the case and is elastically deformed, the action part comes into close contact with the case or the first shaft member, so that the stopper is securely held in the case and is not detached from the case. Here, the leg portion puts the first shaft member in a rotation-restraining condition.
The invention according to Claim 4 is the tensioner described in any one of Claims 1 through 3, and wherein (1) an aperture for mounting a seal bolt is formed in the case, and (2) the stopper is inserted into the case via the aperture.
In the invention described in Claim 4, because the stopper can be inserted into the case via the aperture for mounting the seal bolt, the aperture can be used for both mounting the seal bolt and inserting the stopper. Effects of the Invention
With the present invention, when the stopper is inserted into the case, the stopper comes into close contact with the case or the first shaft member so as to generate friction force, so that the stopper is securely held in the case. Therefore, even when vibrations act on the stopper and the case, or even when the torque of the spring is small, the stopper is not accidentally detached from the case. Also, because the stopper has a simple structure, an inexpensive tensioner can be provided. Brief Descriptions of the Drawings

Figure 1 is a cross-sectional view showing the situation when the stopper is inserted into the first embodiment of the present invention. Figure 2 is a plan view of the first embodiment. Figure 3 is a cross-sectional view of the first embodiment.
Figure 4 consists of a side view (4a) and a front view (4b) of the stopper used in the first embodiment.
Figure 5 is a perspective view showing the situation when the stopper is inserted into the case.
Figure 6 consists of a front view (6a )and a side view (6b) of the stopper used in the second embodiment.
Figure 7 is a cross-sectional view showing the situation when the stopper is inserted into the second embodiment.
Figure 8 consists of a side view (8a) and a front view (8b) of the stopper used in the third embodiment.
Figure 9 is a cross-sectional view showing the situation when the stopper is inserted into the third embodiment.
Figure 10 consists of a front view (10a) and a side view(l0b) of the stopper used in the fourth embodiment.
Figure 11 is a cross-sectional view showing the situation when the stopper is inserted into the fourth embodiment.
Figure 12 consists of a front view (12a) and a side view (12b) of the stopper used in a variation of the fourth embodiment.
Figure 13 is a cross-sectional view showing the situation when the stopper is inserted into a variation of the fourth embodiment. Figure 14 is a cross-sectional view showing the first variation of the fifth embodiment.

Figure 15 is a cross-sectional view showing the second variation of the fifth embodiment.
Figure 16 consists of a cross-sectional view of the aperture 18 (16a) and a cross-sectional
view of the stopper 15 (16b) showing the third variation of the fifth embodiment.
Figure 17 is a cross-sectional view showing the fourth variation of the fifth embodiment.
Figure 18 consists of a front view (18a), and a plan view (18b), and a side view (18c)
showing the first variation of the sixth embodiment.
Figure 19 consists of a front view (19a), a plan view (19b) a side view (19c) showing the
second variation of the sixth embodiment.
Figure 20 consists of a front view (20a), a plan view (20b), and a side view (20c) showing
the third variation of the sixth embodiment.
Figure 21 is a partial side view showing the situation when the tensioner is mounted to an
engine body.
Figures 22(a) and (b) are cross-sectional views showing conventional examples when
variations of the stopper have been inserted into the case.
Figure 23 is a perspective view showing the situation when the stopper of Figure 22(a) is
engaged.
Explanation of Numbers Used in the Drawings
1 tensioner
2 case
3 first shaft member
4 second shaft member
5 spring
6 bearing

8 male screw
9 female screw

15 stopper
15a leg part
15 b locking part
15 c action part
18 aperture
19 engagement groove
Best Modes for Carrying Out the Invention
The present invention will now be described in detail with reference to the embodiments illustrated in the drawings. For each embodiment, identical numbers are used to refer to identical members.
(First Embodiment)
Figures 1 through 5 show a tensioner 1 in a first embodiment of the present invention.
Figure 1 is a cross-sectional view showing that a stopper is inserted.
Figure 2 is a plan view of the tensioner 1.
Figure 3 is a cross-sectional view of the entire tensioner 1. .
Figure 4 is a side view and a plan view of the stopper.
Figure 5 is a perspective view showing that the stopper is inserted.
As shown in Figures 2 and 3, a tensioner 1 comprises a case 2, a first shaft member 3, a second shaft member 4, and a spring 5.
The case 2 has (1) a shell part 2a, (2) a flange part 2b that extends outside from the circumference of the shell part 2a, and (3) an accommodation hole 2c that accommodates the first shaft member 3 and is formed in the shell part 2a in the axial direction (driving direction). The axial-tip portion of the accommodation hole 2c is open,

and the first shaft member 3, the second shaft member 4, and the spring 5 are accommodated in the accommodation hole 2c. The flange 2b is for mounting the tensioner 1 onto an engine body, and a mounting hole 2d, through which penetrates a mounting bolt (not shown) that is to be screwed to the engine body, is formed in the flange part 2b.
The first shaft member 3 and the second shaft member 4 are inserted into the accommodation hole 2c of the case 2 under the condition that the first shaft member 3 and the second shaft member 4 are screwed together. The first shaft member 3 is energized by the spring 5 and rotates, and the second shaft member 4 moves forward in the axial direction of the case 2 from the case 2 due to rotation of the first shaft member 3.
In the first shaft member 3, a shaft part 3 a on the base-end side and a screw shaft part 3b on the tip-end side are integrally formed to extend in the axial direction of the tensioner 1 and a male screw 8 is formed on the outer periphery of the screw shaft part 3b. The second shaft member 4 is formed into a cylindrical shape, and is screwed to the shaft part 3 a of the first shaft member 3. Accordingly, a female screw 9 that is to be screwed with the male screw 8 is formed on the inner face of the second shaft member 4.
A bearing 6 is secured to the tip portion of the case 2 by a snap ring 13. The bearing 6 is slidably penetrated by the second shaft member 4 and restrains the rotation of the second shaft member 4. Accordingly, a slide hole 6a, through which the second shaft member 4 penetrates, is formed in the bearing 6. The inner face of the slide hole 6a and the outer face of the second shaft member 4 are formed to have a cross-section of an approximately oval shape, a D-cut shape, a parallel-cut shape, or other non-circular shape, so that the bearing 6 restrains the rotation of the second shaft member 4. A cap 10 is secured to the tip portion of the second shaft member 4.

In Figure 3, a portion of the first shaft member 3 where the first shaft member 3 and the second shaft member 4 are screwed together is inserted inside a cylindrical spacer 7. The spacer 7 faces the bearing 6 that is fixed to the tip portion of the case 2, and the bearing 6 prevents the spacer 7 from being detached from the case 2. A flange part 3c that has a large diameter is formed at the boundary portion between the shaft part 3 a and the screw shaft part 3b of the first shaft member 3, and the flange part 3c contacts the spacer 7. This prevents the first shaft member 3 and the second shaft member 4 from being detached from the case 2.
A torsion spring is used as a spring 5 that energizes and rotates the first shaft member 3, which penetrates through a coil part of the spring 5. One end 5a of the spring 5 is locked to the case 2, and the other end 5b is locked to the first shaft member 3. Accordingly, when the spring 5 is twisted so as to give a predetermined torque, the first shaft member 3 rotates in the only direction in which it is preset to rotate, and under no condition rotates in the reverse rotation. The rotation force of the first shaft member 3 is transmitted to the second shaft member 4. However, as described above, because the rotation of the second shaft member 4 is restrained by the bearing 6, the rotation force is converted into a drive force, so that the second shaft member 4 does not rotate but instead moves forward in a linear direction from the case 2. This forward movement can give tension to a chain in the engine body.
In order that the other end 5b of the spring 5 is engaged with the first shaft member 3, a slit 12 is formed on the base-end face of the shaft part 3a of the first shaft member 3. The slit 12 is formed so as to extend in the axial direction of the first shaft member 3 from the center portion of the base-end face of the shaft part 3 a. When the other end 5b of the spring 5 is inserted into the slit 12, the other end 5b is engaged with the first

shaft member 3. As described below, a leg part 15a of a stopper 15 is inserted into and engaged with the slit 12.
The rotation of the first shaft member 3 is supported both by the case 2 and by a supporting member that is arranged in the case 2. In Figure 3, a swivel plate 17 is installed in the case 2 as a supporting member. The swivel plate 17 is press-fitted to the base-end side of the accommodation hole 2c of the case 2 and is integrated with the case 2, so that the swivel plate 17, as a supporting member, is a component of the case 2. The inner face of the swivel plate 17 supports both the base-end face and side-face portion of the first shaft member 3 — with said side-face portion extending up from said base-end face — so that the swivel plate 17 supports the rotation of the first shaft member 3.
An aperture 18 that is connected with the accommodation hole 2c is formed in the axial direction of the first shaft member 3 on the base-end side of the case 2. After the below-described stopper 15 is pulled out of the aperture 18, a seal bolt (not shown) is mounted into the aperture 18 by screwing or press-fitting, and the mounted seal bolt seals the case 2 so as to prevent oil from leaking from the case 2. Because the aperture 18 can be used for both mounting the seal bolt and inserting the stopper, the structure of the lower portion of the case 2 shown in Figure 3 can be made simple. An engagement groove 19 is formed on the base-end face of the case 2 and is engaged with the stopper 15.
In this embodiment, the first shaft member 3 is put under a rotation-restraining condition by the stopper 15, and the stopper 15 is inserted through the aperture 18 of the case 2 and engaged with the first shaft member 3.
As shown in Figure 4, the stopper 15 has a leg part 15a, and a wide, locking part 15b that is integrally formed on the base-end side of the leg part 15a. The leg part 15a is inserted into the slit 12 of the first shaft member 3, and is engaged with the first shaft member 3. The locking part 15b is engaged with the engagement groove 19 that is formed

on the base-end face of the case 2. As shown in Figure 5, four engagement grooves 19 are formed on the base-end face of the case 2 in such a way that one pair of the engagement grooves 19 are arranged opposite to each other, and the other pair of the engagement grooves 19 also are also arranged opposite to each other, with the two pairs arranged in such a way that if lines were drawn to connect the two engagement grooves 19 of each pair, the two lines would form a cross. When the locking part 15b is engaged with the engagement grooves 19, and the leg part 15a is engaged with the slit 12, the stopper 15 acts to prevent the rotation of the first shaft member 3 that otherwise would result due to the energizing and rotating force of the spring 5.
In addition, right and left action parts 15c are formed on the stopper 15 integrally with the leg part 15a and the locking part 15b. The right and left action parts 15c extend up from both faces of the locking part 15b in the direction of the leg part 15 a. The action parts 15c extend up from the both side faces of the locking part 15b, and gradually move away from the leg part 15a, so that tip portions of the action parts 15c are free ends. The right and left action parts 15 c have a spring force that is an elastic force that pushes the leg part 15a upward (upward as in Figure 4). The action parts 15c, the leg part 15a, and the locking part 15b can be integrally formed by molding, such as by injection molding using resin or rubber, or by press molding using metals. Also, the action parts 15c, the leg part 15a, and the locking part 15b can be formed using different members or different materials and then be integrated together to be used as the stopper 15.
As shown in Figure 1, in this embodiment, under a free condition before the stopper 15 is inserted into the aperture 18 of the case 2, the maximum interval distance Z between the right and left action parts 15c is set larger than the diameter of the aperture 18. Accordingly, when the stopper 15 is inserted into the aperture 18, the right and left action parts 15c are elastically deformed so as to approach each other and to closely contact the

inner face of the aperture 18. In this manner, when the action parts 15c closely contact the inner face of the aperture 18, friction force is generated between the action parts 15c and the aperture 18, so that the stopper 15 is securely held by the case 2, and is not detached from the case 2.
The actions of this embodiment will now be described in reference to Figures 1 and 5. The first shaft member 3, the second shaft member 4 — which are under the condition that the first shaft member 3 and the second shaft member 4 are screwed together — and the spring 5 are assembled together, and inserted into the case 2. Then, the spring 5 is twisted, so that torque for energizing and rotating the first shaft member 3 is stored. Then, immediately after this twisting, the stopper 15 is inserted into the aperture 18 of the case 2.
The stopper 15 is inserted into the aperture 18 of the case 2 under a free condition such that the right and left action parts 15c are separated from each other at their maximum interval distance Z. The stopper 15 is inserted into the aperture 18 from the leg part 15a as a leading end, that is, from the free-end side of the action parts 15c. The leg part 15a, by being inserted into the aperture 18, is inserted into and engages with the slit 12 of the first shaft member 3. Also, the locking part 15b is inserted into and engaged with the engagement groove 19 on the base-end face of the case 2. In this manner, when the leg part 15a is engaged with the slit 12 and the locking part 15b is engaged with the engagement groove 19, the first shaft member 3 is put under a rotation-restraining condition. In this case, before the leg part 15a is engaged with the first shaft member 3 and the locking part 15b is inserted into the engagement groove 19, the stopper 15 can be rotated. By doing do, the first shaft member 3 is rotated, and the spring 5 is twisted.
When the stopper 15 is inserted into the aperture 18 of the case 2 as described above, the right and left action parts 15c of the stopper 15 are elastically deformed and

closely contact the inner face of the aperture 18, as a result of which the action parts 15c generate a reaction force F against the case 2. Also, because the right and left action parts 15c closely contact the inner face of the aperture 18, a fixing force R, the size of which varies depending on the friction coefficient \x for the close contacting area, is generated in the axial direction of the first shaft member 3. The fixing force R satisfies the formula, R = F,. The larger the reaction force F and the apparent friction coefficient \x, the larger the fixing force R. In this embodiment, because the friction force — generated by close contact of the action parts 15c — holds the stopper 15 so that it is not detached from the aperture 18, the stopper 15 can be securely held in the case 2. Therefore, even when vibrations occur during transportation, the stopper 15 does not move in the axial direction of the first shaft member 3. Even when the torque of the spring 5 is low, the stopper 15 is prevented from being detached from the case 2.
In this embodiment, because the stopper 15 is not detached from the case 2, a special measure for preventing detachment of the stopper 15 is not required. Also, detachment of the stopper 15 is prevented by the friction force that is generated due to the close contact of the action parts 15c with the aperture 18 of the case 2. The magnitude of this friction force can be set freely, irrespective of the torque of the spring 5, and therefore design flexibility is enhanced. Furthermore, because the stopper 15 can have a simple structure and be integrally formed using a single material, it can be provided at low cost.
(Second Embodiment) Figures 6 and 7 show a second embodiment of the present invention. As shown in Figure 6, the stopper 15 of this embodiment is molded into a co-shape as seen from the front. The leg part 15a is positioned in the center, and the action parts 15c are positioned on both sides of the leg part 15a. The leg part 15a and the action parts 15c are integrally formed using a material such as resin or rubber. The action parts 15c extend from the base end of

the leg part 15a in the sideways direction under a curving condition, and extend up more or less parallel to the leg part 15a. The tip portions of the action parts 15c are free ends. The right and left action parts 15c are bent toward the leg part 15a in a manner such that the free ends of the action parts 15c approach the leg part 15a. Thus, a spring property, capable of elastic deformation, is given to the action parts 15c.
Furthermore, on the free-end sides of the right and left action parts 15c, protruding portions 15d that protrude toward the leg part 15a are formed on faces opposite the leg part 15a. The protrusion portions 15d closely contact the case 2 and, due to this close contact, friction force is generated on the action parts 15c. In this embodiment, the right and left action parts 15c also serve as locking parts to be engaged with the case 2.
Figure 7 shows the situation when the stopper 15 is mounted to the case 2 in this embodiment. Engagement grooves 21, which are different from the engagement grooves 19 at the center portion, are formed on the outer peripheral sides of the base end of the case 2. The leg part 15a of the stopper 15 is inserted into the aperture 18 of the case 2, and the tip portion of the leg part 15a is inserted and locked in the slit 12 of the first shaft member 3. Therefore, when the stopper 15 is rotated in a way similar to that described above (in Paragraph [0042]), the spring 5 can be twisted and fastened via the first shaft member 3.
Furthermore, when the stopper 15 is made to approach the case 2, the right and left action parts 15c are inserted into and engaged with the engagement grooves 21, and because the protrusion parts 15d of the action parts 15c closely contact the sidewall portions of the case 2, friction force is generated on those portions. The stopper 15 is securely held in the case 2 by this friction force, so as to prevent detachment of the stopper 15.

(Third Embodiment)
Figures 8 and 9 show a third embodiment of the present invention. As shown in Figure 8, in the stopper 15 of this embodiment, right and left action parts 15c are formed at the leg part 15a. The right and left action parts 15c are integrally formed so as to incline and expand in the sideways direction of the tip of the leg part 15 a. This inclination gives to the action parts 15c a spring property, making them capable of elastic deformation. The maximum interval distance Z between the right and left action parts 15c is set larger than the width of the slit 12 of the first shaft member 3. Also, a wide locking part 15b is integrally formed on the base end of the leg part 15a. In this embodiment also, the stopper 15 is integrally formed using a single material, such as resin, rubber, or metal. Each of the parts, including the action parts 15c, is not to be limited to the above materials, and each can be formed of a different material, and then the parts can be assembled together integrally.
As shown in Figure 9, when the stopper 15 of this embodiment is inserted into the case 2 from the aperture 18, the leg part 15a and the action parts 15c are integrally inserted into the slit 12 of the first shaft member 3. In this insertion, the right and left action parts 15c are elastically deformed in a manner such that the distance between the right and left action parts 15c becomes small. Therefore, the action parts 15c closely contact the inner face of the slit 12 of the first shaft member 3 so as to generate friction force. The action parts 15c are prevented from being detached from the case 2, and thus the stopper 15 is prevented from being detached from the case 2.
In the initial phase of inserting the locking part 15b into the aperture 18, the locking part 15b is not yet engaged with the engagement grooves 19 of the case 2, and therefore it is possible to rotate the stopper 15 so that the first shaft member 3 is rotated and the spring 5 is twisted and fastened. Then, by inserting the stopper 15 further, the

locking part 15b is engaged with the engagement grooves 19, and as a result the first shaft member 3 is put under a rotation-restraining condition. In this embodiment also, the detachment of the stopper 15 can be surely prevented by the action parts 15c.
[0054] (Fourth Embodiment)
Figures 10 and 11 show a fourth embodiment of the present invention. As shown in Figure 10, the stopper 15 of this embodiment is formed somewhat like a U-shape, and its free-end sides are right and left action parts 15c that also serve as leg parts 15a. As shown in Figure 11, the right and left action parts 15c are inserted into the slit 12 of the first shaft member 3, and the maximum interval distance Z between the right and left action parts 15c under a free condition before insertion into the slit 12 is set larger than the diameter of the opening 17a of a swivel plate 17. Also, tapered parts 15e that taper toward the tip ends of the right and left action parts 15c are formed at the tip portions of the right and left action parts 15c. Furthermore, locking parts 15b, which expand outward in a stepped manner, are formed at the base ends of the right and left action parts 15c.
In this embodiment, when the stopper 15 is inserted into the case 2 through the aperture 18, the tapered faces 15e at the tip portions contact the swivel plate 17, so that the action parts 15c are elastically deformed — in a manner so as to reduce the distance between the right and left action parts 15c — and pass through the swivel plate 17. By elastic deformation of the right and left action parts 15c, the outer faces of the action parts closely contact the inner face of the swivel plate 17 and generate friction force that prevents the stopper 15 from being detached from the case 2. Here, the locking parts 15b are engaged with the engagement grooves 19 of the case 2, so that the stopper 15 can put the first shaft member 3 into a rotation-restraining condition.
Figures 12 and 13 show a variation of this embodiment. In this variation, protrusion portions 15 f that prevent the stopper 15 from coming off of the swivel plate 17

are formed outside on the free-end sides of the U-shaped stopper 15. Also in this variation, the right and left action parts 15c closely contact the inner face of the swivel plate 17 so as to generate friction force, so that the stopper 15 can be surely prevented from being detached from the case 2. In addition, in this variation, the protrusion portions 15f are formed on the right and left action parts 15 c, and therefore the fixing force against the swivel plate 17 becomes large, and thus detachment of the stopper 15 can be prevented more surely.
(Fifth Embodiment) Figures 14 to 17 show a fifth embodiment of the present invention. In this embodiment, another relationship between the aperture 18 of the case 2 and the stopper 15 is shown. The stopper 15 has a leg part 15a that is inserted into the slit 12 of the first shaft member 3, a locking part 15b that is engaged with the engagement grooves 19 of the case 2, and right and left elastically-deformable action parts 15 c that have a spring property similar to that of the action parts 15c of the first embodiment.
In a first variation of the fifth embodiment shown in Figure 14, the aperture 18 of the case 2 has a conical shape. The conical aperture 18 is a conical hole that has a gradient 9 and a diameter that is gradually reduced toward the first shaft member 3. In a second variation of the fifth embodiment shown in Figure 15, the inner face of the aperture 18 is made to have projections and indentations like a casting surface. In these embodiments, when the stopper 15 is inserted into the aperture 18, the action parts 15c rigidly closely contact the inside surface of the aperture 18, so that a large friction force is generated. Accordingly, detachment of the stopper 15 from the case 2 can be prevented more surely. In the above-mentioned embodiments, there is no need to specially process the action parts 15c of the stopper 15, or for them to have a special shape. Therefore, the stopper 15 can easily be manufactured at low cost.

Also, wrinkling or multithread processing can be applied to the portion of the aperture 18 that contacts the action parts 15c of the stopper 15, or the aperture 18 can be formed into an inverted conical shape, which is opposite to that in Figure 14. Thus, the friction force against the stopper 15 can be made large, so that the stopper 15 can be stably held in the case 2.
In third and fourth variations of the fifth embodiments shown in Figures 16 and 17, a screw 21 is formed on the inner face of the aperture 18. By forming the screw 21, a seal bolt can be screwed together with the aperture 18 after the stopper 15 is pulled out, so that oil can be prevented from leaking from the case 2. In Figure 16, when the action parts 15c of the stopper 15 contact the threads of the screw 21, friction force is generated. That is to say, the flat portions of the action parts 15c closely contact the screw 21, and therefore the screw 21 is not damaged at the time that the stopper 15 is pulled out from the case 2, which is a merit of the present invention.
In Figure 17, projections and indentations 15g — which correspond to those of the screw 21 — are formed on the right and left action parts 15c of the stopper 15, and these projections and indentations 15g are fitted with the screw 21. Under such a fitting condition, because the action parts 15c rigidly closely contact the inside surface of the aperture 18, the stopper 15 can be fixed to the case 2 more stably.
(Sixth Embodiment) Figures 18 through 20 show a sixth embodiment of the present invention. This embodiment includes variations of the action parts 15c of the stopper 15.
In a first variation of the sixth embodiment shown in Figure 18, the portions of the right and left action parts 15c that contact the case 2, are formed like an arc. An arc-like face 15i is formed so as to extend in the direction in which the stopper 15 is

inserted into the case 2. Therefore, the stopper can rigidly closely contact the inside surface of the aperture 18 of the case 2.
In a second variation of the sixth embodiment shown in Figure 19, the arc-like faces 15i of the right and left action parts 15c are formed shorter than those in the embodiment shown in Figure 18. In this case also, the stopper can rigidly closely contact the inside surface of the aperture 18 of the case 2.
In a third variation of the sixth embodiment shown in Figure 20, projections 15k are formed on the right and left action parts 15c. The projections 15k are formed so has to have inverted shapes so as to project in the direction opposite to the direction in which the stopper 15 is inserted into the aperture 18 of the case 2. By having such an inverted shape, the action parts 15c can rigidly closely contact the inside surface of the aperture 18, so that the stopper 15 can be rigidly held by the case 2.
The present invention is not limited to the above-mentioned embodiments, and it can be changed in various ways. For example, the action parts 15c, which closely contact the case 2 or the swivel plate 17, can be formed into various shapes other than those in the above-described embodiments, and the positions at which the action parts 15c are arranged on the stopper 15 can be changed appropriately. Also, a spring other than a torsion spring, such as a spiral spring, can be used as the spring for energizing and rotating the first shaft member 3. Industrial Applicability
Because the stopper is not detached from the case due to factors such as vibrations during transportation, the present invention can be effectively applied as a tensioner for a belt or chain that is used for a vehicle.

WE CLAIM
1. A tensioner that comprises
a first shaft member and a second shaft member that are screwed into each other by screw parts, and
a spring that rotates and energizes the first shaft member in only one preset direction, with the first shaft member, the second shaft member, and the spring being accommodated in a case,
and that converts the energizing and rotating force of the spring into a drive force for the second shaft member by restraining the rotation of the second shaft member; and wherein a stopper can be inserted into the case so as to engage with the first shaft member so as to resist the energizing and rotating force of the spring and to put the first shaft member in a rotation-restraining condition, and
wherein the stopper has a structure such that it closely contacts the case or the first shaft member so as to generate friction force that prevents the stopper from getting detached from the case.
2. The tensioner described in Claim 1, and wherein said case has a supporting member that supports the rotation of the first shaft member as a component, and wherein said stopper has a structure so that it closely contacts the supporting member so as to generate said friction force.
3. The tensioner described in Claim 1 or 2, and wherein the stopper has
a leg portion that is engaged with the first shaft member, and action parts that have a spring property, and wherein when the leg portion and the action parts are inserted into the case, the action part is elastically deformed, so that the action parts come into close contact with the case or the first shaft member.
4. The tensioner described in any of Claims 1 to 3, and wherein an aperture for mounting

a seal bolt is formed in said case, and wherein said stopper is inserted into the case via
said aperture.

ABSTRACT
To surely prevent a simple-structured, inexpensive stopper from being detached from a case. A tensioner 1 comprises
a first shaft member 3 and a second shaft member 4 that are screwed into each other by screw parts 8 and 9, and
a spring 5 that energizes and rotates the first shaft member 3 in only one preset direction,
with the first shaft member, the second shaft member, and the spring 5 being accommodated in a case 2,
and where said tensioner converts the energizing and rotating force of the spring 5 into a drive force for the second shaft member 4 by restraining the rotation of the second shaft member 4. A stopper 15, which is engaged with the first shaft member 3 so as to put the first shaft member 3 into a rotation-restraining condition that resists the energizing and rotating force of the spring 5, can be inserted into the case 2. The stopper 15 has a structure such that it closely contacts the case 2 or the first shaft member 3 so as to generate friction force for preventing the stopper 15 from being detached from the case 2.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=sRAa9JIWn5tJpg0YgBWbEw==&loc=vsnutRQWHdTHa1EUofPtPQ==

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Patent Number

279654

Indian Patent Application Number

1718/MUMNP/2007

PG Journal Number

05/2017

Publication Date

03-Feb-2017

Grant Date

27-Jan-2017

Date of Filing

18-Oct-2007

Name of Patentee

NHK SPRING CO. LTD.

Applicant Address

10, FUKUURA 3-CHOME, KANAZAWA-KU, YOKOHAMA-SHI, KANAGAWA

Inventors:

#	Inventor's Name	Inventor's Address
1	TANEHIRA AMANO	NHK SPRING CO LTD, 3131 MIYADAMURA, KAMIINA-GUN, NAGANO 399-4301
2	FUMIHISA INOUE	NHK SPRING CO LTD, 3131 MIYADAMURA, KAMIINA-GUN, NAGANO 399-4301
3	TAKAO KOBAYASHI	NHK SPRING CO LTD, 3131 MIYADAMURA, KAMIINA-GUN, NAGANO 399-4301
4	IKUOMI TAKAHASHI	NHK SPRING CO LTD, 3131 MIYADAMURA, KAMIINA-GUN, NAGANO 399-4301

PCT International Classification Number

F16H7/08

PCT International Application Number

PCT/JP2006/308243

PCT International Filing date

2006-04-19

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2005-125739	2005-04-22	Japan