Title of Invention

A METHOD OF INSPECTING A PROPELLING FORCE EXERTING DEVICE

Abstract

A propelling force exerting device 20 for tensioner for presing an endless drive belt 10 via a tensioner in the straining direction to exert a tensile force on the endless drive belt 10 via a propelled member comprising: a pressing body 30 abutted against the propelled member at the front end and provided with a thread 34 at the rear portion thereof;the pressing body being supported by the casing 21 so as not to rotate about the axis but to move along the axis;a revolving shaft having a threaded portion 28 to be screwed on the thread 34;a bearing member 25 interposed between the rear portion of the revolving shaft 26 and the casing 21 for supporting the revolving shaft 26 so as to be capable of rotating about the axis while bearing a propelling reaction force exerted on the revolving shaft 26;and a spring 39 provided between the casing 21 and the revolving shaft 26 for urging the pressing body 30 fordward;characterized in that the pressing force and return torque is set within the compatible region interposed between the allowable wear limit to which one or both the tensioner and the endless drive belt 10 can resist wear and the allowable noise limit of noise generated when the endless drive belt 10 is forwarded on the two-dimensional map using the pressing force which is aprojecting force of the pressing body urged by the spring 39.

Full Text

FORM 2 THE PATENTS ACT 1970 [39 OF 1970] COMPLETE SPECIFICATION [See Section 10 ; rule 13]] "A method of inspecting a propelling force exerting device" HONDA GIKEN KOGYO KABUSHIKI KAISHA., a corporation of Japan having a place of business at 1-1 Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan. The following specification particularly describes the nature of the invention and the manner in which it is to be performed:- ORIGINAL 671/MUMNP/2002 GRANTED 23-5-2007 [Detailed Description of the Invention] [Technical Field to which the Invention Belongs] The present invention relates to an propelling force exerting device used in a tensioner for exerting a tensile force to an endless driving belt such as a cam chain in the internal combustion engine, and more specifically, to a lead-screw type propelling force exerting device. [Prior Art] In recent years, an internal combustion engine with reduced noise and vibrations is required in association with an increased requirement for high-quality internal combustion engines. On the other hand, improvement of durability of the internal combustion engine is required in association with speeding up of the internal combustion engine./ In general, when improving the durability of the cam chain, it is effective to lower a tensile force to be applied on the cam chain by a tensioner, but there is a tendency that lowering of a tensile force on the cam chain increases forwarding noise of the cam chain. Therefore, means for realizing both of improvement of wear resistance and noise reduction has been desired. The propelling force exerting device used in the tensioner for exerting an appropriate tensile force on the cam chain includes a lead-screw type propelling force exerting device which is simple in structure without using hydraulic pressure and provides reliable performance. As an example of inventions realizing the aforementioned requirements, there is an invention disclosed in Japanese Patent Laid-Open In the aforementioned lead-screw type propelling force exerting device, the proximal end portion of the revolving shaft that is screwed into the pressing body is rotatably supported by the casing via a bearing member, and a spring is provided for urging the pressing body in the projecting direction all the time, so that the pressing body is projected by a urging force of the spring and the tensioner exerts a required tensile force on the cam chain. In the invention disclosed in Japanese Patent Laid-Open NO.82557/2001 described above, in order to prevent lowering of a pressing force of the pressing body with respect to the cam chain due to wear of either one or both of the proximal end surface and the corner of the inner peripheral surface of the revolving shaft and the end surface and the corner of the outer peripheral surface of the bearing member after long term of use and thus reduction of the diameter of the portion in contact, the proximal end surface of the bearing member is inclined by a prescribed angle with respect to the plane orthogonal to the centerline of the bearing member to improve durability. In addition, in order to reduce forwarding noise of the cam chain generated during operation of the internal combustion engine, the spring constant of the spring for urging the revolving shaft and an initial urging force of the spring have been controlled. [Problems that the Invention is to Solve] However, when a pressing force of the propelling force exerting device for tensioner is increased to lower the noise level of the cam chain to a large extent, a repulsive force generated at the propelling force exerting device when a tensile force of the cam chain is increased grows eminently. Consequently, wear of the cam chain and the tensioner is promoted, and thus the tensile force of the cam chain is lowered adversely in a short time period, thereby impairing quiet operation. [Means for Solving the Problems and Advantages] The Inventors focused attention on the fact that the noise of the cam chain during forwarding and durability of the cam chain and the like is caused not only by a pressing force exerted on the tensioner by the propelling force exerting device, but also by a resistance force generated when the pressing body of the propelling force exerting device is pushed back. As a result, the inventor came to have an idea to digitize the resistance force as a return torque and set return torque and the pressing force in the compatible region between the allowable wear limit and allowable noise limit on a two-dimensional map using return torque and pressing force as variables. The pressing force described above is defined as a projecting force of the pressing body urged by the spring, and return torque is defined as a torque that is required for exerting a constant load in the direction against the pressing force of the propelling force exerting device and turning the revolving shaft at a constant number of revolution while overcoming an urging force and a frictional force of the spring. Being based on such idea, the present invention according to Claim 1 is a propelling force exerting device for tensioner for pressing a endless drive belt via a tensioner in the straining direction to exert a tensile force on the endless drive belt comprising: a pressing body abutted against the tensioner at the front end and provided with a thread at the rear portion thereof; the pressing body being supported by the casing so as not to rotate about the axis but to move along the axis; a revolving shaft having a threaded portion to be screwed on the thread; a bearing member interposed between the rear portion of the revolving shaft and the casing for supporting the revolving shaft so as to be capable of rotating about the axis while bearing a propelling reaction force exerted on the revolving shaft; and a spring provided between the casing and the revolving shaft for urging the pressing body forward; characterized in that the pressing force and return torque is set within the compatible region interposed between the allowable wear limit to which one or both of the tensioner and the endless drive belt can resist wear and the allowable noise limit of noise generated when the endless drive belt is being forwarded on the two-dimensional map using the pressing force which is a projecting force of the pressing body urged by the spring and return torque required for rotating the revolving shaft while overcoming the urging force and frictional force of the spring to force the pressing body to be retracted at a constant speed in a state in which a constant load is exerted on the pressing body as variables. Since the invention according to Claim 1 is constructed as described above, the pressing force and return torque is set within the compatible region interposed between the allowable wear limit to which one or both of the tensioner and the endless drive belt can resist wear and the allowable noise limit of the noise generated when the endless drive belt is forwarded by varying one or two or more of the tooth lead angle of the thread in the propelling force exerting device for tensioner, effective friction diameter between the revolving shaft and bearing member, and spring constant of the spring, and varying a initial urging force of the spring or the like to bring up the noise generated by the endless drive belt and durability of the endless drive belt and the tensioner to the optimal level. By constructing the invention as set forth in Claim 2, a propelling force exerting device wherein the pressing body is formed in the shape of a cylinder having a female thread on the inner peripheral surface thereof and the revolving shaft is formed with male thread on the outer peripheral surface thereof can be provided. In addition, by constructing the invention as set forth in Claim 3, inspection of the propelling force exerting device according to Claim 1 can be performed. Further, by constructing the invention as set forth in Claim 4, the propelling force exerting device as set forth in Claim 1 can be applied to the lifter for the cam chain tensioner in the internal combustion engine. Still further, by constructing the invention as set forth in Claim 5, the method of inspecting the propelling force exerting device as set forth in Claim 3 can be applied to the method of inspecting the lifter for the cam chain tensioner in the internal combustion engine. In addition, by constructing the invention as set forth in Claim 6, setting of the pressing force and return torque of the propelling force exerting device can reliably be performed. Further, by constructing the invention as set forth in Claim 7, the pressing force of the propelling force exerting device can be exerted effectively on the tensioner. Still further, by constructing the invention as set forth in Claim 8, wear resistance and deformation resistance can be given to the bearing member. In addition, by constructing the invention as set forth in Claim 9, the compatible region interposed between the allowable wear limit and the allowable noise limit can be broaden by lowering torque required for rotating the revolving shaft in the reverse direction without changing prescribed diameter of the end surface of the revolving shaft and the tooth lead angle of the thread. Further, by constructing the invention as set forth in Claim 10, steep fluctuation in repulsive force against the pressing force exerted from the pressing body to the endless drive belt can be damped, and thus durability of the endless drive belt and the propelling force exerting device can be improved. [Mode for Carrying Out the Invention] The embodiment shown in the drawing to which the invention is applied will now be described. [Brief Description of the Drawings] [Fig. 1] Fig. 1 is a right side view of the motorcycle provided with an internal combustion engine including a propelling force exerting device for tensioner according to the present invention mounted thereon. [Fig. 2] Fig. 2 is a vertical cross sectional side view showing a principal portion of the internal combustion engine shown in Fig. 1. [Fig. 3] Fig. 3 is a vertical cross sectional side view showing an embodiment of the propelling force exerting device for tensioner according to the present invention. [Fig. 4] Fig. 4 is a vertical cross sectional side view showing a method of inspecting an embodiment of the propelling force exerting device according to the present invention. [Fig. 5] Fig. 5 is a two-dimensional map using the pressing force N and return torque T in the propelling force exerting device as variables. 2, the cylinder head 3, and the crankcase 4 are integrally combined with each other by a nut to be screwed on the bolt or a stud bolt, not shown, and a cylinder head cover 5 is integrally combined above the cylinder head 3. A crankshaft 6 is rotatably supported on the mating surface between the cylinder block 2 and the crankcase 4, and a piston (not shown) is slidably fitted into the cylinder bore, not shown, formed on the cylinder head 3. The piston and the crankshaft 6 are connected via a connecting rod, not shown, so that the crankshaft 6 is rotated as the piston is reciprocated by combustion gas generated in the combustion chamber of the cylinder. Further, two camshafts 7 are rotatably supported on the mating surface between the cylinder head 3 and the cylinder head cover 5, and the camshafts 7 are provided with driven sprockets 8 fitted integrally on one end thereof respectively. An endless cam chain 10 (toothed belt is also applicable) is routed between a drive sprocket 9 integrally provided at one of the crankshaft 6 and the driven sprocket 8, so that when the crankshaft 6 rotates, the camshaft 7 is rotated at half the speed of rotation of the crankshaft 6. The cylinder head 3 is formed with an intake passage and an exhaust passage, not shown, in communicate with the combustion chamber, and an intake valve and an exhaust valve, not shown, are provided so as to bring into communication or to block between the combustion chamber and the air intake passage and the exhaust passage. The intake valve and the exhaust valve are connected to the cam (not shown) of the camshaft 7 via the locker arm or a valve lifter, not shown, so that, corresponding to the rotation of the camshaft 7, the intake valve and the exhaust valve are opened and closed at a prescribed timing while the crankshaft 6 makes two revolutions and the camshaft 7 makes one revolution. The proximal end 11a of the tensioner 11 is pivotally supported by the cylinder block 2 at the position close to the crankshaft 6, and the chain shoe 11b of the tensioner 11 is abutted against the cam chain between the drive sprocket 9 of the crankshaft 6 and the driven sprocket 8 of the cam shaft 7. At the position close to the distal end portion of the tensioner 11, the propelling force exerting device 20 is mounted on the cylinder head 3, and on the opposite side, a chain guide 12 is attached to the cam chain 10, so that the pressing force is exerted from the propelling force exerting device 20 onto the back portion 11e of the tensioner 11, and the cam chain 10 is strained by an appropriate tensile force as will be described later. The construction of the propelling force exerting device 20 will now be described. In the propelling force exerting device 20, the casing 21 formed of aluminum is formed with a storing hole 22, a mounting hole 23 that is smaller in diameter than the storing hole 22 coaxially on the bottom thereof, and a threaded hole 24 that is smaller in diameter than the mounting hole 23 coaxially toward the bottom. A cylindrical bearing member 25 with one side closed and having a hole on the bottom formed of hard carbon tool steel, especially of SK material, is integrally fitted in the mounting hole 23. The threaded hole 24 is constructed in such a manner that after the rotary motion of the stopper 40 is terminated, the pressing body 30 of the propelling force exerting device 20 is projected, and an appropriate stain force is applied to the cam chain 10, a screw, not shown, is screwed into the threaded hole 24 to close the threaded hole 24 tightly as will be described later. A proximal column portion 27 of the rotary shaft 26 is rotatably fitted in the bearing member 25, and the revolving shaft 26 is formed with a male thread 28 at the distal end portion thereof in the range longer than the stroke along which the pressing body 30 can project or retract. The proximal column portion 27 is formed with a groove 29 of a prescribed depth and width on the proximal end surface oriented in the direction of diameter. In addition, the pressing body 30 comprises a proximal cylindrical portion 31, a distal end member 32 integrally mounted on the distal end by means of a pin 32a, and a contact body 33 integrally fitted on the distal end member 32 via a resilient body 33a. The proximal end portion of the proximal cylindrical portion 31 is formed with a female thread 34 in the range longer than about one-fourth the male thread 2 8, or longer than two pitches of the thread, and the male thread 28 is screwed into the female thread 34. The outer peripheral surface of the proximal cylindrical portion 31 is formed with flat surfaces parallel with each other on the both sides of the cylindrical surface so that the rotation of the pressing body 30 is prevented by the parallel portion of the hole 36a of the cap 36 that will be described later and the flat surface of the proximal cylindrical portion. A guide cylinder 35 is loosely fitted in the proximal column portion 27 of the revolving shaft 26, and the proximal end of the proximal cylindrical portion 31 of the pressing body 30 is slidably inserted in the guide cylinder 35. A cap 36 for preventing the guide cylinder 35 from projecting and preventing the rotation of the proximal cylindrical portion 31 by being contact with the flap surface formed on both sides of the proximal cylindrical portion 31 of the pressing body 30 is fitted on the proximal cylindrical portion 31. A plurality of engaging claws 37 radially projecting from the cap 36 along the circumference thereof are engaged with the notch 21a at the distal end of the casing 21, and then a retaining ring 38 is attached in a circumferential groove 21b formed at the distal end of the casing 21 so that the cap 36 is engaged at the distal end of the casing 21. Furthermore, a coil spring 39 is interposed between the storing hole 22 of the casing 21 and the proximal column portion 27 of the revolving shaft 26 and the guiding cylinder 35, and the proximal end 3 9a of the coil spring 39 is bent at a right angle and engaged with the groove 29 of the proximal column portion 27, and then the distal end 39b of the coil spring 39 s projected outward from the casing 21 and locked in the notched shoulder 21c thereof. The casing 21 is formed with a oil feed hole 21d from the distal end of the casing 21 toward the mounting hole 23, and with a locking notch 21e in the shape of a cross when viewed from outside along the centerline of the threaded hole 24 on the outer periphery of the lower end of the threaded hole 24. In the propelling force exerting device 2 0 shown in Fig. 3, the revolving shaft 2 6 and the coil spring 3 9 are attached in the storing hole 22 of the casing 21 with the proximal bent portion 39a of the coil spring 39 engaged with the groove 29 formed on the proximal cylindrical portion 27 of the revolving shaft 26, and the distal end 39a of the coil spring 39 engaged with the notched shoulder 21c of the casing 21. In such a state, a stopper 4 0 is inserted from the end of the opening of the threaded hole 24 of the casing 21, and the distal end 40a of the stopper 40 is engaged with the groove 29 of the proximal column portion 27, and then the stopper 40 is twisted counterclockwise when viewed in the direction opposite from the direction A in Fig. 3 by a prescribed number of revolutions to provide the coil spring 39 clockwise return torque. Then the proximal overhanging portion 40b of the stopper 40 is engaged with the locking notch 21e of the casing 21, and the revolving shaft 26 is fixed so as not to rotate. Subsequently, the female thread 34 of the pressing body 30 is placed on the distal end of the male thread 28 of the revolving shaft 26 with the cap 36 fitted on the proximal cylindrical portion 31, then the pressing body 30 is rotated clockwise when viewed in the direction A to screw the female thread 34 toward the proximal end of the male thread 2 8 to engage the engaging claw 37 of the cap 36 with the distal notch 21a of the casing 21, and then the retaining ring 38 is attached in the distal circumferential groove 21b of the casing 21, so that a pressing force is generated at the propelling force exerting device 20. As shown in Fig. 2, when the stopper 40 is pulled out after the casing 21 of the propelling force exerting device 20 is mounted integrally on the cylinder head 3 so that the contact body 33 of the propelling force exerting device 20 abuts against the back portion l1C of the tensioner 11, restoring spring torque of the coil spring 39 for rotating the revolving shaft 26 clockwise when viewed in the direction A is released, and thus the revolving shaft 26 rotates in the same direction. Therefore, the pressing body 30 projects while being prevented from rotating by the cap 36, and thus provides a tensile force to the cam chain 10 via the tensioner 11. The pressing force N to project the pressing body 30 is determined by restoring spring torque of the coil spring 39, the diameter of the end surface D1 of the revolving shaft 26, friction coefficient between the revolving shaft 26 and the bearing member 25, tooth lead angle a of the male thread 28 and the female thread 34, and friction coefficient between the male thread 28 and the female thread 34. In the same way, a repulsive resistance generated when the contact body 33 abuts against the back portion l1C of the tensioner 11 and the pressing body 30 is pushed back via the tensioner 11 by a tensile force of the cam chain 10 is also determined by the same values described above. If the pressing force N to project the pressing body 30 and a repulsive resistance generated when the pressing body 30 is pushed back is not larger than a certain value, ruffling phenomenon of the cam chain 10 while being forwarded cannot be prevented, thereby generating noise. In contrast to it, when the pressing force or repulsive resistance is too large, a large tensile force generates at the cam chain 10, and frictional force between the cam chain 10 and the tensioner 11 increases to a large extent, and thus the cam chain 10 and the tensioner 11 are worn out and lowered in durability. Since the repulsive resistance is not static but dynamic, the Inventor measured return torque T from which dynamic repulsive resistance can be estimated by the use of a test apparatus 50 shown in Fig. 4. In the test apparatus 50 shown in Fig. 4, the holding cylinder 53 for holding the casing 21 of the propelling force exerting device 20 is installed stably on the top board 52 of the stand 51, and the top board 52 is formed with a hole 54 in which the stopper 40 can be inserted and rotated. ■[QQ42J-- In order to measure returning torque T by the use of the test apparatus 50, a turning device, not shown, is disposed from below the top board 52 , and a revolving tip claw (not shown) thereof is engaged with the groove 29 on the proximal column portion 27, and then a plumb bob 55 of a prescribed weight is placed on the proximal cylindrical portion 31 to secure the same with the pressing body 30 projected from the casing 21 by a prescribed length. Then, the revolving shaft 26 is rotated counterclockwise when viewed in the direction A by the turning device against the spring force of the coil spring 3 9 that urges the pressing body 30 in the projecting direction, and torque required for pulling the pressing body 30 back at a prescribed speed, in other words, for retracting the pressing body 30 into the casing 21 is measured by the torque sensor in the turning device. Torque obtained in this procedure is so called return torque T. (Q0d3] When measured data described above is plotted in the two-dimensional map having the pressing force N of the pressing body 30 described above on the abscissa axis and return torque T as a variable, a line X connecting ■ and the line Y connecting and , and the line Z connecting ♦ and can be obtained as shown in Fig. 5. The line X obtained by connecting ■ and is a characteristic line in the case where the end surface diameter D1 of proximal column portion 27 of the revolving shaft 26 is 12 mm, and the tooth lead angle a of the male thread 28 and the female thread 34 is 12 degrees, the line Y obtained by connecting ▲ and A is a characteristic line in the case where the end surface diameter D1is 12 mm, and the tooth lead angle a is 14 degrees, and the line Z obtained by connecting ♦ and O is a characteristic line in the case where the end surface diameter D1 is 9 mm, and the tooth lead angle a is 12 degrees. More specifically, the characteristic line X, representing the characteristic in the case where the end surface diameter D1 of the proximal column portion 27 of the revolving shaft 26 is large and the tooth lead angle a of the male thread 28 and the female thread 34 is small, shows that the effect of the frictional force on a constant pressing force N is significant and thus return torque T is large. The characteristic line Y, representing the characteristic in the case where the end surface diameter D1 is the same as X, and the tooth lead angle a is larger, shows that the effect of the frictional force on the constant pressing force N is light, and thus return torque T is small. The characteristic line Z, representing the characteristic in the case where the tooth lead angle a is the same as X, but the end surface diameter D1 is small, shows that the effect of the frictional force on the constant pressing force N is still lighter, and thus return torque T is significantly small. Further, in the characteristic lines X, Y, and z, the parts on the left side show that the number of twists applied to the coil spring 39 is small, and thus the values of pressing force N and returning torque T are small, while the parts on the right side show that the number of twists is large, and thus the values of pressing force N and return torque T are large. As a result of conducting experiments, the Inventor found that in the case where the propelling force exerting device 20 is installed on the front cylinder head 3 of the V-type four cylinder internal combustion engine 1 of 800 cc displacement, the limits of the pressing force N and return torque T required to suppress the noise level generated by the cam chain 10 below the allowable noise level are represented by the line S in Fig. 5, and if the pressing force N and return torque T are smaller than this allowable noise level S, the noise generated by the cam chain 10 exceeds the allowable level, and thus it is required to increase values of the pressing force N and return torque T to the level exceeding the allowable noise level S. Further, as a result of conducting experiments, the Inventor found that in the case where the propelling force exerting device 20 is installed on the front cylinder head 3 of the v-type four cylinder internal combustion engine 1 of 800 cc displacement, the limits of the pressing force N and return torque T required to maintain wear of the cam chain 10 and the tensioner 11 below the allowable level is represented by the line w in Fig 5, and if the pressing force N and return torque T are larger than this allowable wear limit W, wear of the cam chain 10 and the tensioner 11 increases, and thus it is necessary to lower the pressing force N and return torque T to the level below this allowable wear limit W. {0040] - In addition, the Inventor can, in the case where the propelling force exerting device 20 is installed on the front cylinder head 3 of the V-type four-cylinder internal combustion engine 1 of 800 cc displacement, lower the noise generating at the cam chain 10 to the allowable level and provide practical level of durability to the cam chain 10 and the tensioner 11 by setting the pressing force N and return torque T to the compatible region AL interposed between the allowable noise limit S and the allowable wear limit W. Furthermore, as a result of the aforementioned three types of tests, it was found that the propelling force exerting device 2 0 in which the end surface diameter D1 of the proximal column portion 27 of the revolving shaft 26 is 12 mm and the tooth lead angle a is 14 degrees, showing a characteristic represented by a characteristic line Y, is most preferable. In addition, by applying coating at least on one of the bearing member 25, the revolving shaft 26, and the pressing body 30, frictional force in the propelling force exerting device 20 can be lowered, and thus the wear resistance limit W in Fig. 5 can be moved upward to increase the lengths Xlf Yl Z1 of the characteristic lines X, Y, Z passing through the compatible region AL in the propelling force exerting device 20. [0052] In addition, the propelling force exerting device 20, being oriented at an almost right angle with respect to the line connecting the proximal end 11a and the back portion l1C of the tensioner 11, can bear the pressing force and return resistance of the propelling force exerting device 20 effectively. Though the spring for urging the revolving shaft 26 in the rotating direction is a coil spring 39 in the aforementioned embodiments, it may be a voluted spring wound vorticosely. Though the revolving shaft 2 6 is formed with the male thread 28 and the proximal cylindrical portion 31 of the pressing body 30 is formed with the female thread 34 in the aforementioned embodiment, it is also possible to form the female thread 34 on the revolving shaft 26, and the male thread 2 8 on the proximal cylindrical portion 31. [Description of the Reference Numerals and Signs] 0. . .motorcycle, 1...internal combustion engine, 2...cylinder block, 3...cylinder head, 4...crankcase, 5...cylinder head cover, 6...crankshaft, 7...cam shaft, 8...driven sprocket, 9...drive sprocket, 10...cam chain, 11...tensioner, 12...chain guide, 2 0...propelling force exerting device, 21...casing, 22...storing hole, 23...mounting hole, 24...thread hole, 25...bearing member, 2 6...revolving shaft, 2 7...proximal column portion, 28...male thread, 29...groove, 30...pressing body, 31...proximal cylindrical portion, 32..distal end member, 33...contact body, 34...female thread, 35...guiding cylinder, 36...cap, 37...engaging claw, 3 8...retaining ring, 39...coil spring, 40...stopper, 50...test apparatus, 51...stand, 52...top board, 53...holding cylinder, 54 — hole, 55...plumb bob WE CLAIM: 1. A method of analyzing forces on cam chain of engines using a propelling force exerting device for tensioner for pressing an endless drive belt via tensioner in the straining direction to exert a tensile force on the endless drive belt comprising: pressing body abutted against the tensioner at the front end and provided with a thread; the pressing body being supported by the casing so as not to rotate about the axis but to move along the axis; a revolving shaft having a threaded portion to be screwed on the thread; a bearing member interposed between the rear portion of the revolving shaft and the casing for supporting the revolving shaft so as to be capable of rotating about the axis while bearing a propelling reaction force exerted on the revolving shaft; and a spring provided between the casing and the revolving shaft for urging the pressing body forward; characterized in that the criterion is whether or not the pressing force and return torque exist within the compatible region interposed between the allowable wear limit to which on or both of the tensioner and the endless drive belt can resist wear and the allowable noise limit of noise generated when the endless drive belt is being forwarded on the two-dimensional map using the pressing force which is a projecting force of the pressing body urged by the spring and return torque required for rotating the revolving shaft while overcoming the urging force and frictional force of the spring to force the pressing body to be retracted at a constant speed in a state in which a constant load is exerted on the pressing body as variables. 2. A method of analyzing forces on cam chain of engines using a propelling force exerting device for tensioner as claimed in claim 1, wherein said pressing body is a cylindrical pressing body formed with female thread on the inner peripheral surface thereof, and the threaded portion of the revolving shaft is a male thread. 3. A method of analyzing forces on cam chain of engines using a propelling force exerting device for tensioner as claimed in claim 1, wherein the method of inspecting the propelling force exerting device is a method of inspecting a lifter for a cam chain tensioner in an internal combustion engine. 4. A method of analyzing forces on cam chain of engines using a propelling force exerting device for tensioner as claimed in claim 1, wherein setting of the pressing force and return torque is made by changing either one of or both of the end surface diameter of the revolving shaft and the tooth lead angle. 5 A method of analyzing forces on cam chain of engines using a propelling force exerting device substantially as herewith described with reference to the accompanying drawings. Dated 26th day of July, 2002. [RAJANAILAVADI] Of Remfry & Sagar Attorney for the applicants

Documents:

671-mum-2002-abstract(23-5-2007).doc

671-mum-2002-abstract(23-5-2007).pdf

671-mum-2002-cancelled pages(23-5-2007).pdf

671-mum-2002-claims(granted)-(23-5-2007).doc

671-mum-2002-claims(granted)-(23-5-2007).pdf

671-mum-2002-correspondence(5-2-2008).pdf

671-mum-2002-correspondence(ipo)-(22-1-2008).pdf

671-mum-2002-drawing(26-7-2002).pdf

671-mum-2002-form 1(22-5-2007).pdf

671-mum-2002-form 18(26-5-2006).pdf

671-mum-2002-form 2(granted)-(23-5-2007).doc

671-mum-2002-form 2(granted)-(23-5-2007).pdf

671-mum-2002-form 3(12-4-2004).pdf

671-mum-2002-form 3(22-5-2007).pdf

671-mum-2002-form 3(26-7-2002).pdf

671-mum-2002-form 5(26-7-2002).pdf

671-mum-2002-petition under rule 137(23-5-2007).pdf

671-mum-2002-petition under rule 138(23-5-2007).pdf

671-mum-2002-power of authority(16-10-2002).pdf

671-mum-2002-power of authority(23-5-2007).pdf

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