Title of Invention	"CONTINUOUSLY VARIABLE TRANSMISSION APPARATUS"
Abstract	A continuously variable transmission apparatus comprising: an inputting member; an outputting member rotatable around the same axial line as that of said inputting member; a planetary gear mechanism having a sun gear connected to said inputting member; a ring gear; planetary gears meshing with said sun gear and said ring gear; and a planetary carrier rotatably supporting said planetary gears and connected to said outputting member; a rotation control member having the same rotational axial line as that of said inputting member; a one-way clutch, provided between said rotation control member and a fixed member, for restraining the rotation of said rotation control member in the direction reversed to the rotational direction of said inputting member and permitting the rotation of said rotation control member in the same direction as the rotational direction of said inputting member; a first centrifugal clutch, provided between said ring gear and said rotation control member speed of said inputting member reaches a first preset rotational speed and completing the engagement when the rotational speed of said inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch,, provided between said inputting member and said ring gear, for starting the engagement thereof when the rotational speed of said inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of said inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed.

Title of Invention

"CONTINUOUSLY VARIABLE TRANSMISSION APPARATUS"

Abstract

A continuously variable transmission apparatus comprising: an inputting member; an outputting member rotatable around the same axial line as that of said inputting member; a planetary gear mechanism having a sun gear connected to said inputting member; a ring gear; planetary gears meshing with said sun gear and said ring gear; and a planetary carrier rotatably supporting said planetary gears and connected to said outputting member; a rotation control member having the same rotational axial line as that of said inputting member; a one-way clutch, provided between said rotation control member and a fixed member, for restraining the rotation of said rotation control member in the direction reversed to the rotational direction of said inputting member and permitting the rotation of said rotation control member in the same direction as the rotational direction of said inputting member; a first centrifugal clutch, provided between said ring gear and said rotation control member speed of said inputting member reaches a first preset rotational speed and completing the engagement when the rotational speed of said inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch,, provided between said inputting member and said ring gear, for starting the engagement thereof when the rotational speed of said inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of said inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed.

Full Text	[Detailed Description of the Invention] [Applicable Industrial Field] The present invention relates to a continuously variable transmission for performing power transmission at a transmission gear ratio continuously variable between an input side and an output side. [Related Art] A continuously variable transmission using an endless belt has been known, for example, in Japanese Patent Laid-open No. [ Problem to be Solved by the Invention] The above-described related art belt-type continuously variable transmission, however, has disadvantages that the service life is poor because of wear of a belt and deterioration of the transmission gear ratio due to the wear; the transmission efficiency, particularly, on the high speed side is relatively low; and the structure is difficult to be made compact because the input side and output side are arranged to be separated from each other. In view of the foregoing, the present invention has been made, and an object of the present invention is to provide a continuously variable transmission capable of enhancing the service life and transmission efficiency with a compact structure. [Means for Solving the Problem] To achieve the above object, according to a preferred mode of the present invention, there is provided a continuously variable transmission including an inputting member; an outputting member rotatable around the same axial line as that of the inputting member; a planetary gear mechanism including a sun gear connected to the inputting member, a ring gear, planetary gears meshing with the sun gear and the ring gear, and a planetary carrier rotatably supporting the planetary gears and connected to the outputting member; a rotation control member having the same rotational axial line as that of the inputting member; a one-way clutch, provided between the rotation control member and a fixed member, for restraining the rotation of the rotation control member in the direction reversed to the rotational direction of the inputting member and permitting the rotation of the rotation control member in the same direction as the rotational direction of the inputting member; a first centrifugal clutch, provided between the ring gear and the rotation control member, for starting the engagement thereof when the rotational speed of the inputting member reaches a first preset rotational speed and completing the ' engagement when the rotational speed of the inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch, provided between the inputting member and the ring gear, for starting the engagement thereof when the rotational speed of the inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed. [Function] According to the above-described configuration of the continuously variable transmission, when a power having a rotational speed less than the first preset rotational speed is inputted in the inputting member, the ring gear is rotated in the direction reversed to the rotational direction of the inputting member by the rotation of the planetary gears depending on the rotation of the sun gear of the planetary gear mechanism. However, since the engagement of the first centrifugal clutch is not started at the rotational speed less than the first preset rotational speed, the ring gear is permitted to idle in the direction reversed to the rotational direction of the inputting member, as a result of which a power is not transmitted from the inputting member to the outputting member. When the rotational speed of the inputting member reaches the first preset rotational speed, the engagement of the first centrifugal clutch is started. At this time, a rotational power in the reverse direction to the rotational direction of the inputting member, which corresponds to the engagement force of the first centrifugal clutch, is transmitted to the rotation control member, while the rotational power in the direction reversed to the rotational direction of the inputting member is retrained by the one-way clutch. As a result, the ring gear is braked in accordance with the engagement force of the first centrifugal clutch, and the planetary carrier of the planetary gear mechanism is rotated in the same direction as that of the sun gear, that is, the inputting member in accordance with the rotational speed of the ring gear. A rotational power is thus transmitted to the planetary carrier, that is, the outputting member at a transmission gear ratio variable based on a change in the engagement force of the first centrifugal clutch depending on a change in the rotational speed of the inputting member. When the rotational speed of the inputting member is further increased to the second preset rotational speed, the engagement force of the first centrifugal clutch is maximized and the rotation of the ring gear is perfectly stopped, so that a rotational power is transmitted from the inputting member to the outputting member at a constant transmission gear ratio determined by the planetary gear mechanism. When the rotational speed of the inputting member reaches the third preset rotational speed, the engagement of the second centrifugal clutch is started, and thereby the ring gear is connected to the inputting member by the engagement force of the second centrifugal clutch and it is rotated in the same direction as that of the inputting member. A rotational power is thus transmitted to the outputting member at a transmission gear ratio variable based on a change in the engagement force of the second centrifugal clutch depending on a change in the rotational speed of the inputting member. At this time, the first centrifugal clutch is also in the engagement state; however, since the rotation control member is permitted to be rotated in the same direction as that of the inputting member, the ring gear is permitted to be rotated in the same direction as that of the inputting member. When the rotational speed of the inputtng member reaches the fourth preset rotational speed, the engagement of the second centrifugal clutch is completed and the ring gear is rotated in the state being perfectly integrated with the inputting member, so that the inputting member and the outputting member are rotated in the state being integrated with each other. Accordingly, the present invention relates to a continuously variable transmission apparatus comprising: an inputting member; an outputting member rotatable around the same axial line as that of said inputting member; a planetary gear mechanism having a sun gear connected to said inputting member; a ring gear; planetary gears meshing with said sun gear and said ring gear; and a planetary carrier rotatably supporting said planetary gears and connected to said outputting member; a rotation control member having the same rotational axial line as that of said inputting member; a one-way clutch, provided between said rotation control member and a fixed member, for restraining the rotation of said rotation control member in the direction reversed to the rotational direction of said inputting member; a first centrifugal clutch, provided between said ring gear and said rotation control member for starting eh engagement thereof; and a second centrifugal clutch, provided between said inputting member and said ring gear, for starting the engagement thereof [Brief Description of the Accompanying Drawing] [Fig. 1] A vertical sectional view of a first embodiment of a continuously variable transmission of the present invention. [Fig. 2] A schematic view showing the configuration of the continuously variable transmission. [Fig. 3] An enlarged sectional view taken on line 3-3 of Fig. 1- [Fig. 4] An enlarged sectional view taken on line 4-4 of Fig. 1- [Fig. 5] A graph showing a transmission torque characteristic. [Fig. 6] A graph showing a load characteristic of a disc spring. [Fig. 7] A vertical sectional view showing an essential portion of a second embodiment of the continuously variable transmission of the present invention. [Explanation of Character] 8: continuously variable transmission 12: inputting member 13: outputting member 14: planetary gear mechanism 16: rotation control member 17: fixed shaft as fixed member 18: one-way clutch 19: first centrifugal clutch 20, 20: second centrifugal clutch 35: sun gear 36: ring gear 37: planetary carrier 38: planetary gear [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the drawings. A first embodiment of the present invention is shown in Figs. 1 to 6. Fig. 1 is a vertical sectional view of a continuously variable transmission; Fig. 2 is a schematic view showing the configuration of the continuously variable transmission; Fig. 3 is an enlarged sectional view taken on line 3-3 of Fig. 1; Fig. 4 is an enlarged sectional view taken on line 4-4 of Fig. 1; Fig. 5 is a graph showing a transmission torque characteristic; and Fig. 6 is a graph showing a load characteristic of a disc spring. Referring first to Fig. 1, a transmission case 5 for containing a continuously variable transmission 8 is joined to the side portion of an engine mounted on a motor-bicycle (not shown). The continuously variable transmission 8 is interposed between an engine crank shaft 6 and an output gear 7 relatively rotatably supported on the crank shaft 6. The output gear 7 meshes with a reduction gear 9 connected to a drive wheel (not shown). A cylindrical bush 10 is mounted around the crank shaft 6. An inputting member 12 as one component of the continuously variable transmission 8 is spline-connected to the crank shaft 6, and a nut 11 for holding the inputting member 12 between the bush 10 and the same is screwed with the end portion of the crank shaft 6. The output gear 7 is relatively rotatably supported on the crank shaft 6 through the bush 10. Referring to Figs. 1 and 2, the continuously variable transmission 8 includes the inputting member 12 spline-connected to the crank shaft 6; an outputting member 13 rotatable around the same axial line as that" of the inputting member 12; a planetary gear mechanism 14 and a first one-way clutch 15 provided between the inputting member 12 and the outputting member 13; a rotation control member 16 rotatable around the same axial line as that of the inputting member 12; a second one-way clutch 18 provided between the rotation control member 16 and a fixed shaft (fixed member) 17 fixed on the transmission case 5 in line with the rotation control member 16; a first centrifugal clutch 19 provided between a ring gear 36 of the planetary gear mechanism 14 and the rotation control member 16; and a second centrifugal clutch 20 provided between the inputting member 12 and the ring gear 36. The inputting member 12 is formed in a disk shape on a plane perpendicular to the axial line of the crank shaft 6 . The inner peripheral portion of the inputting member 12 is spline-connected to the crank shaft 6. The outputting member 13 is formed in a cylindrical shape coaxially surrounding the bush 10. The outputting member 13 is relatively rotatably supported on the crack shaft 6 through the bush 10 with one end thereof being in sliding-contact with the inputting member 12. A gear 21, meshing with the output gear 7, is provided at the other end of the output ting member 13 . The inputting member 12 is integrally provided with a cylindrical portion 12a coaxially surrounding the outputting member 13 . The first one-way clutch 15 is provided between the cylindrical portion 12a and the outputting member 13 . Referring to Fig. 3, the one-way clutch 15 includes the outputting member 13; the cylindrical portion 12a of the inputting member 12; a plurality of roller keys 22 disposed between the outputting member 13 and the cylindrical portion 12a in such a manner as to be spaced at intervals in the circumferential direction; and a spring 23 commonly locked with the outer sides of the roller keys 22 . A plurality of inward recesses 24 are provided in the outer peripheral surface of the outputting member 13 in such a manner as to be spaced at intervals along the circumferential direction. The inner peripheral surface of the cylindrical portion 12a is closely opposed to the outer peripheral surface of the outputting member 13, and a plurality of outward recesses 25 corresponding to the inward recesses 24 are provided in the inner peripheral surface of the cylindrical portion 12a. The inward recess 24 includes an inward meshing portion 26 capable of meshing with the inner side of the roller key 22; and an inward inclined surface 27 continuous at one end to the inward meshing portion 26 and inclined radially outward as nearing one side (left side in Fig. 3) of the outputting member 13 in the circumferential direction. The inward meshing portion 26 is formed in an arcuate shape capable of being substantially brought in press-contact with the outer surface of an inner quarter portion of the roller key 22 . The outward recess 25 includes a containing portion 28 capable of containing the entire roller key 22; an outward inclined surface 29 continuous at one end to the containing portion 28 and inclined radially inward as nearing one side (left side in Fig. 3) of the outputting member 13 in the circumferential direction; and an outward meshing portion 30 continuous to the other end of the outward inclined surface 29 for holding the roller key 22 between the inward meshing portion 26 and the same. More specifically, the containing portion 28 is formed in such a shape as to contain the entire roller key 22 for preventing the roller key 22 from being brought in contact with the outer peripheral surface of the output ting member 13 . The outward meshing portion 30 is formed in such an arcuate shape as to hold the roller key 22 between the inward meshing portion 26 and the same. An annular locking groove 31 is formed in the outer periphery of each of the roller keys 22 at the axial center portion. The spring 23 is formed of a spring wire curved in such a manner that both the ends form a nearly circular shape in a free condition in which any external force is not applied. The spring 23 is locked from the outer side into the locking grooves 31 of all of the roller keys 22. When locked in all of the roller keys 22, the spring 23 is in a state that both the ends are separated from each other, and in such a state, it exhibits a spring force biasing all of the roller keys 22 each to the inward recesses 24. An annular groove 32 is opened in the inner peripheral surface of the cylindrical portion 12a for containing the spring 23 in such a state as to allow the displacement of the spring 23 due to the movement of the roller keys 22. The function of the first one-way clutch 15 will be described below. When the outputting member 13 is rotated in the direction where the inward meshing portion 26 of each inward recess 24 meshes with the roller key 22 as shown by an arrow 33 in Fig. 3, the roller key 22 is held between the inward meshing portion 26 of the inward recess 24 and the outward meshing portion 30 of the outward recess 25 in a state that the rotational speed of the outputting member 13 is less than a preset rotational speed determined by the spring force, and thereby a power transmission is performed between the outputting member 13 and the cylindrical portion 12a of the inputting member 12. The first one-way clutch thus comes to be in the power transmission state. Next, when the crank shaft 6, that is, the cylindrical portion 12a is rotated at a rotational speed more than that of the outputting member 13, each roller key 22 is contained in the containing portion 28 of the outward recess 25 against the spring force of the spring 23, so that the power transmission between the cylindrical portion 12a of the inputting member 12 and the outputting member 13 is cut off. Referring again to Figs. 1 and 2, the planetary gear mechanism 14 includes the sun gear 35; the ring gear 36 coaxially surrounding the sun gear 35; a plurality of the planetary gears 38 meshing with the sun gear 35 and the ring gear 36; and the planetary carrier 37 rotatably supporting the planetary gears 38. The sun gear 35 is spline-connected to the outer periphery of the leading end of the cylindrical portion 12a of the inputting member 12; the planetory carrier 37 is connected to the outputting member 13; and the ring gear 36 is formed integrally with one end of the cylinder 39. The fixed shaft 17 is fixed on the transmission case 5 in line with the crank shaft 6, and the rotation control member 16 is disposed in such a manner as to coaxially surround the fixed shaft 17. Referring to Fig. 4, the second one-way clutch 18 includes an inner clutch 41 spline-connected to the fixed shaft 17; an outer clutch 42 fixed in the rotation control member 16 by press-fitting or the like in such a manner as to coaxially surround the inner clutch 41; a plurality of roller keys 43 disposed between the inner clutch 41 and the outer clutch 42 in such a manner as to be spaced at intervals in the circumferential direction; and a spring 44 commonly locked with the outer sides of the roller keys 43 . A plurality of inward recesses 45 are provided in the outer peripheral surface of the inner clutch 41 in such a manner as to be spaced at intervals in the circumferential direction. The inner peripheral surface of the outer clutch 42 is closely opposed to the outer peripheral surface of the inner clutch 41, and a plurality of outward recesses 46 corresponding to the inward recesses 45 are provided in the inner peripheral surface of the outer clutch 42. The inward recess 45 includes an inward meshing portion 47 capable of meshing with the inner side of the roller key 43; and an inward inclined surface 48 continuous at one end to the inward meshing portion 47 and inclined radially outward as nearing one side (left side in Fig. 4) of the inner clutch 41 in the circumferential direction. The inward meshing portion 47 is formed in an arcuate shape capable of being substantially brought in press-contact with the outer surface of an inner quarter portion of the roller key 43 . The outward recess 46 includes a containing portion 49 capable of containing the entire roller key 43; an outward inclined surface 50 continuous at one end to the containing portion 49 and inclined radially inward as nearing one side (left side in Fig. 4) of the inner clutch 41 in the circumferential direction; and an outward meshing portion 51 continuous to the other end of the outward inclined surface 50 for holding the roller key 43 between the inward meshing portion 47 and the same. More "specifically, the containing portion 49 is formed in such a shape to contain the entire roller key 43 for preventing the roller key 43 from being brought in contact with the outer peripheral surface of the inner clutch 41. The outward meshing portion 51 is formed in such an arcuate shape as to hold the roller key 43 between the inward meshing portion 47 and the same. An annular locking groove 52 is formed in the outer periphery of each of the roller keys 43 at the axial center portion. The spring 44 is formed of a spring wire curved in such a manner that both the ends form a nearly circular shape in a free condition in which any external force is not applied. The spring 44 is locked from the outer side in the locking grooves 52 of all of the roller keys 43 . When locked with all of the roller keys 43 , the spring 44 is in a state that both the ends are separated from each other, and in such a state, it exhibits a spring force biasing all of the roller keys 43 to the inward recesses 45. An annular groove 53 is opened in the inner peripheral surface of the outer clutch 42 for containing the spring 44 in such a state as to allow the displacement of the spring 44 due to the movement of the roller keys 43 . The function of the second one-way clutch 18 will be described below. When the outer clutch 42 integrated with the rotation control member 16 is rotated in the direction reversed to the rotational direction of the inputting member 12, that is, in the direction where the outward meshing portion 51 meshes with each roller key 43 as shown by an arrow 54 in Fig. 4, the roller key 43 is held between the outward meshing portion 51 of the outward recess 46 and the inward meshing portion 47 of the inward recess 45, so that a power is intended to be transmitted from the outer clutch 42, that is, the rotation control member 16 to the inner clutch 41; however, since the inner clutch 41 is spline-connected to the fixed shaft 17, the rotations of the outer clutch 42 and the rotation control member 16 are restrained. On the other hand, when the outer clutch 42 is rotated in the same direction as that of the inputting member 12 as shown by an arrow 55 in Fig. 4, each roller key 22 is contained in the containing portion 49 of the outward recess 46 against the spring force of the spring 44, as a result of -which the outer clutch 42, that is, the rotation control member 16 idles around the fixed shaft 17. The first centrifugal clutch 19 includes the cylinder 39 integrated at one end with the ring gear 36 and surrounding the rotation control member 16; a plurality of outer clutch plates 57 provided between the rotation control member 16 and the cylinder 39 in such a manner that the outer peripheries thereof are spline-connected to the cylinder 39; one or a plurality of inner clutch plates 58 alternately arranged between the outer clutch plates 57 in such a manner that the outer peripheries thereof are spline-connected to the rotation control member 16; a pressure receiving plate 59 mounted on the inner surface of the cylinder 39 in such a manner as to face the outer surface of the outermost outer clutch plate 57; a spring 60 compressed between the innermost and the outermost outer clutch plates 57; a plurality of rolling balls 62 rotatably supported by a holding plate 61 facing the inner surface of the innermost outer clutch plate 57 and brought in rolling-contact with the inner surface of the innermost outer clutch plate 57; a pressing plate 63 disposed opposite to the outer clutch plates 57 with-respect to the holding plate 61 and brought in rolling-contact with the rolling balls 62; a cam plate 64 provided integrally with the inputting member 12 in such a manner as to be positioned opposite to the holding plate 61 with respect to the pressing plate 63 and to face the pressing plate 63; and a plurality of centrifugal balls 65 disposed between the cam plate 64 and the pressing plate 63. A plurality of cam surfaces 64a are provided on the surface, opposite to the pressing plate 63, of the cam plate 64 in such a manner as to be spaced at intervals. The cam surface 64a is inclined in such a manner as to come near the pressing plate 63 as extending radially outward of the cam plate 64 and brought in rolling-contact with the centrifugal balls 65. A stopper ring 83 engaged with the innermost outer clutch plate 57 from the holding plate 61 side, is fitted on the inner surface of the cylinder 39. The set load of the spring 60 is determined by the stopper ring 83. The function of the first centrifugal clutch 19 will be described below. Each centrifugal ball 64 is applied with a centrifugal force by rotation of the inputting member 12, that is, the cam plate 64, and it moves radially outward of the cam plate 64 along the cam surface 64a in proportion to the centrifugal force, as a result of which the pressing plate 63 presses the innermost outer clutch plate 57 against the spring force of the spring 60. When the pressing force of the pressing plate 63 overcomes the spring force of the spring 60 and allows the outer and inner clutch plates 57, 58 to be friction-engaged with each other, the cylinder 39, that is, the ring gear 36 is connected to the rotation control member 16. In this case, the spring force of the spring 60 is so determined that the frictional engagement of the centrifugal clutch 19 is started by a pressing force generated at the pressing plate 63 when the rotational speed of the inputting member 12, that is, the cam plate 64 reaches a first preset rotational speed, for example, the rotational speed upon starting a motor-bicycle, and the frictional engagement of the centrifugal clutch 19 is completed when the rotational speed of the inputting member 12 reaches a second preset rotational speed more than the first preset rotational speed. The second centrifugal clutch 20 includes a first pressure receiving plate 66 radially inward protruding from a portion, of the cylinder 39, near the ring gear 36 on one end side; a second pressure receiving plate 67 disposed at a position separated from the first pressure receiving plate 66 on the cam plate 64 side in such a manner that the outer peripheral portion thereof is spline-connected to the cylinder 39; a plurality of spherical rolling balls 69 rotatably supported by a holding plate 68 disposed between the second pressure receiving plate 67 and the cam plate 64, and brought in rolling-contact with the second receiving plate 67 and the cam plate 64; a spring 70 compressed between the first and second pressure receiving plates 66, 67; a first friction plate 71 facing the first pressure receiving plate 66 for free frictional engagement therewith, and spline-connected at its inner periphery with the cylindrical portion 12a of the inputting member 12; a second friction plate 72 facing the second pressure receiving plate 67 for free frictional engagement therewith, and spline-connected at its inner periphery with the cylindrical portion 12a; and a disc spring 74 provided between the first friction plate 71 and a stop ring 75 mounted on the outer surface of the cylindrical portion 12a at a position separated from the first friction plate 71 on the sun gear 35 side. The outer peripheral portion of the first friction plate 71 is liquid-tightly fitted to the outer peripheral portion of the second friction plate 72, and a liquid chamber 73 is formed between the outer peripheral portions of the first and second friction plates 71, 72. A stopper ring 84 engaged with the second pressure receiving plate 67 from the holding plate 68 side is mounted on the cylinder 39. The set load of the spring 70 is determined by the stopper ring 84. The function of the second centrifugal clutch 20 will be described below. A lubricating liquid held between both the friction plates 71, 72 is applied with a centrifugal force by rotation of the inputting member 12, that is, the first and second friction plates 71, 72, and it moves to the liquid chamber 73 side, with a result that the pressure in the liquid chamber 73 is increased. The pressure in the liquid chamber 73 acts to separate the friction plates 71, 72 from each other. When such a pressure overcomes the spring force of the disc spring 74 and acts to move the first friction plate 71 to the extent that the first friction plate 71 is friction-engaged with the first pressure receiving plate 66, the second friction plate 72 is also friction-engaged with the second pressure receiving plate 67. As a result, the cylinder 39,- that is, the ring gear 36 is connected to the cylindrical portion 12a, that is, the inputting member 12. In this case, the spring force of the disc spring 74 is so determined that the frictional engagement of the second friction plate 20 is started by a pressing force generated at the first friction plate 71 when the rotational speed of the inputting member 12 reaches a third preset rotational speed more than the second preset rotational speed of -the first centrifugal clutch 19, and the frictional engagement is completed when the rotational speed of the inputting member 12 reaches a fourth preset rotational speed more than the third preset rotational speed. Incidentally, a cover 78 is mounted on the cam plate 64 in such a manner that a lubricating sump 77 is formed between the cover 78 and the cam plate 64, and a lubricating liquid passage 79 provided in the transmission case 5 and the fixed shaft 17 is communicated to the lubricating sump 77 . A supply passage 81 is provided in the inputting member 12 for introducing the lubricating liquid in the lubricating sump 77 between the inner peripheral portions of the first and second friction plates 71, 72. The function of the first embodiment will be described with reference to Fig. 5. When a rotational power is supplied from a kick starter (not shown) to the output member 13 of the first one-way clutch 15 through the output gear 7 as shown by the arrow 33 of Fig. 3, the output member 13 is rotated in the direction where the inward meshing portion 26 of the inward recess 24 meshes with each roller key 22. At this time, the roller key 22 is held between the outward meshing portion 30 of the outward recess 25 and the inward meshing portion 26 of the inward recess 24 in a state that the rotational speed of the outputting member 13 is less than the preset rotational speed determined by the spring force of the spring 23, so that the power transmission is performed between the outputting member 13 and the cylindrical portion 12a of the inputting member 12 impossible to be relatively rotatable with respect to the crank shaft 6. Namely, the first one way clutch 15 is turned in the power transmission state, and accordingly the power supplied from the kick starter is inputted to the crank shaft 6 and thereby the engine is started. On the other hand, the sun gear 35 and the planetary carrier 37 in the planetary gear mechanism 14 are rotated in a state being integrated with each other along with the power transmission from the outputting member 13 to the inputting member 12 through the first one-way clutch 15. Thus, the ring gear 36 is also rotated in the same direction as the rotational direction of the inputting member 12 together with the sun gear 35 and the planetary carrier 37. However, since the rotational speed of the inputting member 12 is less than the first preset rotational speed, the first centrifugal clutch 19 is in the power cut-off state, as a result of which the ring gear 36 idles . When the engine is started and the crank shaft 6, that is, the cylindrical portion 12a of the inputting member 12 is started to be rotated at a rotational speed more than that of the outputting member 13, each roller key 22 in the first one-way clutch 15 is contained in the containing portion 28 of the outward recess 25 against the spring force of the spring 23 . The power transmission by the first one-way clutch 15 is thus cut off, and thereby the rotational power of the crank shaft 6 is not transmitted to the outputting member 13 . When the engine speed is increased up to a first preset rotational speed N1 more than the idling rotational speed, the ring gear 36, that is, the cylinder 39 is rotated in the direction reversed to the rotational direction of the inputting member 12 along with the rotation of the sun gear 35 together with the inputting member 12, and the engagement of the first centrifugal clutch 19 is started. As a result, a rotational power in the direction reversed to the rotational direction of the inputting member 12 , which corresponds to the engagement force of the centrifugal clutch 19, is transmitted to the rotation control member 16. However, since the rotation of the rotation control member 16 in the direction reversed to the rotational direction of the inputting member 12 is restrained by the second one-way clutch 18, the rotation of the cylinder 39, that is, the ring gear 36 is braked. In other words, the ring gear 36 is braked on the basis of the engagement force of the first centrifugal clutch 19. Thus, the planetary carrier 37 in the planetary gear mechanism 14 is rotated in the same direction as that of the sun gear 35, that is, the inputting member 12 in accordance with the rotational speed of the ring gear 36 at a transmission gear ratio variable based on a change in the engagement force of the first centrifugal clutch 19 depending on a change in the rotational speed of the inputting member 12 . The transmitting torque between the inputting member 12 and the outputting member 13 is thus increased linearly with the rotational speed of the inputting member 12 . When the rotational speed of the inputting member 12 is further increased up to a second preset rotational speed N2, the frictional engagement of the first centrifugal clutch 19 is maximized, and thereby the rotation of the ring gear 36 is perfectly stopped. As a result, the rotational power is transmitted from the inputting member 12 to the outputting member 13 at a constant transmission gear ratio determined by the planetary gear mechanism 14. In other words, a power is transmitted to the outputting member 13 in proportion to the engine speed. This mode is used for the low speed running of the motor-bicycle. When the rotational speed of the inputting member 12 reaches a third preset rotational speed N3 more than the second preset rotational speed N2, the engagement of the second centrifugal clutch 20 is started, and the ring gear 36 is connected to the inputting member 12 by the engagement force of the second centrifugal clutch 20 and it is rotated in the same direction as the rotational direction of the inputting member 12. Namely, the rotational power is transmitted to the outputting member 13 at a transmission gear ratio variable based on a change in the engagement force of the second centrifugal clutch 20 depending on the rotational speed of the inputting member 12. In this case, the first centrifugal clutch 19 is also in the engagement state; however, since the rotation control member 16 is allowed to be rotated in the same direction as the rotational direction of the inputting member 12, the ring gear 36 is allowed to be rotated in the same direction as the rotational direction of the inputting member 12 . When the rotational speed of the inputting member 12 reaches a fourth preset rotational seed N4 more than the third preset rotational speed N3, the frictional engagement of the second centrifugal clutch 20 is completed, so that the ring gear 36 and the cylinder 39 are rotated in the same direction as the rotational direction of the inputting member 12 in a state being integrated therewith. The inputting member 12 and the outputting member 13 are thus rotated in a state being integrated with each other through the planetary gear mechanism 14 along with the integral rotation of the sun gear 34, ring gear 36 and inputting member 12. This mode is used for the high speed running of the motor-bicycle. The load characteristic of the disc spring 74 of the second centrifugal clutch 20 is shown in Fig. 6. When the maximum load is taken as the set load, the spring load of the disc spring 74 is lower than the set load when the frictional engagement of the second centrifugal clutch 20 is completed. Accordingly, the high speed running state is continued until the rotational speed becomes a value less than the fourth preset rotational speed N4 upon deceleration, as shown by a broken line in Fig. 5. As described above, according to the continuously variable transmission of the present invention, it is possible to make small in size by arranging the inputting member 12 and the outputting member 13 on the same axial line, and to enhance the durability as compared with the related art belt-type continuously variable transmission. In addition, an ordinary transmission efficiency on the low speed side can be obtained by the planetary gear mechanism 14 and a high transmission efficiency on the high speed side can be obtained by direct coupling between the inputting member 12 and the outputting member 13. Fig. 7 shows a second embodiment, wherein parts corresponding to those in the first embodiment are indicated by the same characters. A second centrifugal clutch 20 provided between an inputting member 12 and a ring gear 36 includes a first pressure receiving plate 66 radially outward protruding from a cylinder 39; a second pressure receiving plate 67 spline-connected at its outer periphery with the cylinder 39; a plurality of spherical rolling balls 69 rotatably supported by a holding plate 68 and brought in rolling-contact with the second pressure receiving plate 67 and a cam plate 64; a spring 70 compressed between both the pressure receiving plates 66, 67; a first friction plate 71 facing the first pressure receiving plate 66; and a second friction plate 72' facing the second pressure receiving plate 67; and a disc spring 74 exhibiting a spring force in the direction of moving the first friction plate 71 to the second friction plate 72 ' . The inner peripheral portion of the second friction plate 72' is spline-connected to the outer periphery of a cylindrical portion 12a of the inputting member 12. The inner peripheral portion of the first friction plate 71 is spline-connected to the inner peripheral portion of the second friction plate 72 . The outer peripheral portion of the first friction portion 71 is liquid-tightly fitted to the outer peripheral portion of the second friction plate 72. A liquid chamber 73 is formed between the outer peripheral portions of the first and second friction plates 71, 72. A stop ring 75 is fitted on the outer surface of the inner peripheral portion of the second friction plate 72' and the disc spring 74 is provided between the stop ring 75 and the first friction plate 71. The second embodiment is effective to assemble the continuously variable transmission as a whole, because the first friction plate 71, second friction plate 72', disc spring 74, and the stop ring 74 can be previously assembled as a unit. This makes it possible to improve the assembling efficiency. While the embodiments of the present invention have been described, such description is for illustrative purposes only, and it is to be understood that many changes in design may be made without departing from the spirit or scope of the claims. [Effect of the Invention] As described above, the continuously variable transmission of the present invention includes: an inputting member; an outputting member rotatable around the same axial line as that of the inputting member; a planetary gear mechanism including a sun gear connected to the inputting member, a ring gear, planetary gears meshing with the sun gear and the ring gear, and a planetary carrier rotatably supporting the planetary gears and connected to the outputting member; a rotation control member having the same rotational axial line as that of the inputting member; a one-way clutch, provided between the rotation control member and a fixed member, for restraining the rotation of the rotation control member in the direction reversed to the rotational direction of the inputting member and permitting the rotation of the rotation control member in the same direction as the rotational direction of the inputting member; a first centrifugal clutch, provided between the ring gear and the rotation control member, for starting the engagement thereof when the rotational speed of the inputting member reaches a first preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch, provided between the inputting member and the ring gear, for starting the engagement thereof when the rotational speed of the inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed. Such a continuously variable transmission is effective to obtain a compact structure in which an inputting member and an outputting member are arranged on the same axial line, to enhance the durability as compared with the related art belt-type continuously variable transmission, and to obtain a high transmission efficiency. We Claim: 1. A continuously variable transmission apparatus comprising: an inputting member (12); an outputting member (13) rotatable around the same axial line as that of said inputting member (12); a planetary gear mechanism (14) having a sun gear (35) connected to said inputting member (12); a ring gear (36); planetary gears (38) meshing with said sun gear (35) and said ring gear (36); and a planetary carrier (37) rotatably supporting said planetary gears (38) and connected to said outputting member (13); a rotation control member (16) having the same rotational axial line as that of said inputting member (12); a one-way clutch (18), provided between said rotation control member (16) and a fixed member (17), for restraining the rotation of said rotation control member (16) in the direction reversed to the rotational direction of said inputting member (12); a first centrifugal clutch (19), provided between said ring gear (36) and said rotation control member (16) for starting the engagement thereof; and a second centrifugal clutch (20, 20'), provided between said inputting member (12) and said ring gear (36), for starting the engagement thereof. 2. A continuously variable transmission apparatus substantially as hereinbefore described with reference to and as illustrated in the foregoing description and accompanying drawings.

Full Text

[Detailed Description of the Invention] [Applicable Industrial Field]
The present invention relates to a continuously variable transmission for performing power transmission at
a transmission gear ratio continuously variable between an input side and an output side.
[Related Art]
A continuously variable transmission using an endless belt has been known, for example, in Japanese Patent Laid-open No.
[ Problem to be Solved by the Invention]
The above-described related art belt-type continuously variable transmission, however, has disadvantages that the service life is poor because of wear of a belt and deterioration of the transmission gear ratio due to the wear; the transmission efficiency, particularly, on the high speed side is relatively low; and the structure is difficult to be made compact because the input side and output side are arranged to be separated from each other.
In view of the foregoing, the present invention has been made, and an object of the present invention is to provide a continuously variable transmission capable of enhancing the service life and transmission efficiency with a compact structure.
[Means for Solving the Problem]
To achieve the above object, according to a preferred mode of the present invention, there is provided a continuously variable transmission including an inputting member; an outputting member rotatable around the same axial line as that of the inputting member; a planetary gear mechanism including a sun gear connected to the inputting member, a ring gear, planetary gears meshing with the sun gear and the ring gear, and a planetary carrier rotatably supporting the planetary gears and connected to the outputting member; a rotation control member having the same rotational axial line as that of the inputting member; a one-way clutch, provided between the rotation control member and a fixed member, for restraining the rotation of the rotation control member in the direction reversed to the rotational direction of the inputting member and permitting the rotation of the rotation control member in the same direction as the rotational direction of the inputting member; a first centrifugal clutch, provided between the ring gear and the rotation control member, for starting the engagement thereof when the rotational speed of the inputting member
reaches a first preset rotational speed and completing the ' engagement when the rotational speed of the inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch, provided between the inputting member and the ring gear, for starting the engagement thereof when the rotational speed of the inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed.
[Function]
According to the above-described configuration of the continuously variable transmission, when a power having a rotational speed less than the first preset rotational speed is inputted in the inputting member, the ring gear is rotated in the direction reversed to the rotational direction of the inputting member by the rotation of the planetary gears depending on the rotation of the sun gear of the planetary gear mechanism. However, since the engagement of the first centrifugal clutch is not started
at the rotational speed less than the first preset rotational speed, the ring gear is permitted to idle in the direction reversed to the rotational direction of the inputting member, as a result of which a power is not transmitted from the inputting member to the outputting member. When the rotational speed of the inputting member reaches the first preset rotational speed, the engagement of the first centrifugal clutch is started. At this time, a rotational power in the reverse direction to the rotational direction of the inputting member, which corresponds to the engagement force of the first centrifugal clutch, is transmitted to the rotation control member, while the rotational power in the direction reversed to the rotational direction of the inputting member is retrained by the one-way clutch. As a result, the ring gear is braked in accordance with the engagement force of the first centrifugal clutch, and the planetary carrier of the planetary gear mechanism is rotated in the same direction as that of the sun gear, that is, the inputting member in accordance with the rotational speed of the ring gear. A rotational power is thus transmitted to the planetary carrier, that is, the outputting member at a transmission gear ratio variable based on a change in the
engagement force of the first centrifugal clutch depending on a change in the rotational speed of the inputting member. When the rotational speed of the inputting member is further increased to the second preset rotational speed, the engagement force of the first centrifugal clutch is maximized and the rotation of the ring gear is perfectly stopped, so that a rotational power is transmitted from the inputting member to the outputting member at a constant transmission gear ratio determined by the planetary gear mechanism. When the rotational speed of the inputting member reaches the third preset rotational speed, the engagement of the second centrifugal clutch is started, and thereby the ring gear is connected to the inputting member by the engagement force of the second centrifugal clutch and it is rotated in the same direction as that of the inputting member. A rotational power is thus transmitted to the outputting member at a transmission gear ratio variable based on a change in the engagement force of the second centrifugal clutch depending on a change in the rotational speed of the inputting member. At this time, the first centrifugal clutch is also in the engagement state; however, since the rotation control member is permitted to be rotated in the same direction as that of
the inputting member, the ring gear is permitted to be rotated in the same direction as that of the inputting member. When the rotational speed of the inputtng member reaches the fourth preset rotational speed, the engagement of the second centrifugal clutch is completed and the ring gear is rotated in the state being perfectly integrated with the inputting member, so that the inputting member and the outputting member are rotated in the state being integrated with each other.
Accordingly, the present invention relates to a continuously variable
transmission apparatus comprising:
an inputting member;
an outputting member rotatable around the same axial line as that of said
inputting member;
a planetary gear mechanism having a sun gear connected to said inputting
member; a ring gear; planetary gears meshing with said sun gear and said
ring gear; and a planetary carrier rotatably supporting said planetary gears
and connected to said outputting member;
a rotation control member having the same rotational axial line as that of
said inputting member;
a one-way clutch, provided between said rotation control member and a
fixed member, for restraining the rotation of said rotation control member in
the direction reversed to the rotational direction of said inputting member;
a first centrifugal clutch, provided between said ring gear and said rotation
control member for starting eh engagement thereof; and
a second centrifugal clutch, provided between said inputting member and
said ring gear, for starting the engagement thereof
[Brief Description of the Accompanying Drawing] [Fig. 1]
A vertical sectional view of a first embodiment of a continuously variable transmission of the present
invention.
[Fig. 2]
A schematic view showing the configuration of the
continuously variable transmission.
[Fig. 3]
An enlarged sectional view taken on line 3-3 of
Fig. 1-
[Fig. 4]
An enlarged sectional view taken on line 4-4 of
Fig. 1-
[Fig. 5]
A graph showing a transmission torque
characteristic.
[Fig. 6]
A graph showing a load characteristic of a disc spring.
[Fig. 7]
A vertical sectional view showing an essential portion of a second embodiment of the continuously variable transmission of the present invention. [Explanation of Character] 8: continuously variable transmission 12: inputting member
13: outputting member
14: planetary gear mechanism
16: rotation control member
17: fixed shaft as fixed member
18: one-way clutch
19: first centrifugal clutch
20, 20: second centrifugal clutch
35: sun gear
36: ring gear
37: planetary carrier
38: planetary gear
[Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A first embodiment of the present invention is shown in Figs. 1 to 6. Fig. 1 is a vertical sectional view of a continuously variable transmission; Fig. 2 is a schematic view showing the configuration of the continuously variable transmission; Fig. 3 is an enlarged sectional view taken on line 3-3 of Fig. 1; Fig. 4 is an enlarged sectional view taken on line 4-4 of Fig. 1; Fig. 5 is a graph showing a transmission torque characteristic; and Fig. 6 is a graph showing a load characteristic of a
disc spring.
Referring first to Fig. 1, a transmission case 5 for containing a continuously variable transmission 8 is joined to the side portion of an engine mounted on a motor-bicycle (not shown). The continuously variable transmission 8 is interposed between an engine crank shaft 6 and an output gear 7 relatively rotatably supported on the crank shaft 6. The output gear 7 meshes with a reduction gear 9 connected to a drive wheel (not shown).
A cylindrical bush 10 is mounted around the crank shaft 6. An inputting member 12 as one component of the continuously variable transmission 8 is spline-connected to the crank shaft 6, and a nut 11 for holding the inputting member 12 between the bush 10 and the same is screwed with the end portion of the crank shaft 6. The output gear 7 is relatively rotatably supported on the crank shaft 6 through the bush 10.
Referring to Figs. 1 and 2, the continuously variable transmission 8 includes the inputting member 12 spline-connected to the crank shaft 6; an outputting member
13 rotatable around the same axial line as that" of the inputting member 12; a planetary gear mechanism 14 and a first one-way clutch 15 provided between the inputting member 12 and the outputting member 13; a rotation control member 16 rotatable around the same axial line as that of the inputting member 12; a second one-way clutch 18 provided between the rotation control member 16 and a fixed shaft (fixed member) 17 fixed on the transmission case 5 in line with the rotation control member 16; a first centrifugal clutch 19 provided between a ring gear 36 of the planetary gear mechanism 14 and the rotation control member 16; and a second centrifugal clutch 20 provided between the inputting member 12 and the ring gear 36.
The inputting member 12 is formed in a disk shape on a plane perpendicular to the axial line of the crank shaft 6 . The inner peripheral portion of the inputting member 12 is spline-connected to the crank shaft 6. The outputting member 13 is formed in a cylindrical shape coaxially surrounding the bush 10. The outputting member 13 is relatively rotatably supported on the crack shaft 6 through the bush 10 with one end thereof being in sliding-contact with the inputting member 12. A gear 21, meshing
with the output gear 7, is provided at the other end of the output ting member 13 .
The inputting member 12 is integrally provided with a cylindrical portion 12a coaxially surrounding the outputting member 13 . The first one-way clutch 15 is provided between the cylindrical portion 12a and the outputting member 13 .
Referring to Fig. 3, the one-way clutch 15 includes the outputting member 13; the cylindrical portion 12a of the inputting member 12; a plurality of roller keys 22 disposed between the outputting member 13 and the cylindrical portion 12a in such a manner as to be spaced at intervals in the circumferential direction; and a spring 23 commonly locked with the outer sides of the roller keys 22 .
A plurality of inward recesses 24 are provided in the outer peripheral surface of the outputting member 13 in such a manner as to be spaced at intervals along the circumferential direction. The inner peripheral surface of the cylindrical portion 12a is closely opposed to the outer peripheral surface of the outputting member 13, and a
plurality of outward recesses 25 corresponding to the inward recesses 24 are provided in the inner peripheral surface of the cylindrical portion 12a.
The inward recess 24 includes an inward meshing portion 26 capable of meshing with the inner side of the roller key 22; and an inward inclined surface 27 continuous at one end to the inward meshing portion 26 and inclined radially outward as nearing one side (left side in Fig. 3) of the outputting member 13 in the circumferential direction. The inward meshing portion 26 is formed in an arcuate shape capable of being substantially brought in press-contact with the outer surface of an inner quarter portion of the roller key 22 .
The outward recess 25 includes a containing portion 28 capable of containing the entire roller key 22; an outward inclined surface 29 continuous at one end to the containing portion 28 and inclined radially inward as nearing one side (left side in Fig. 3) of the outputting member 13 in the circumferential direction; and an outward meshing portion 30 continuous to the other end of the outward inclined surface 29 for holding the roller key 22
between the inward meshing portion 26 and the same. More specifically, the containing portion 28 is formed in such a shape as to contain the entire roller key 22 for preventing the roller key 22 from being brought in contact with the outer peripheral surface of the output ting member 13 . The outward meshing portion 30 is formed in such an arcuate shape as to hold the roller key 22 between the inward meshing portion 26 and the same.
An annular locking groove 31 is formed in the outer periphery of each of the roller keys 22 at the axial center portion. The spring 23 is formed of a spring wire curved in such a manner that both the ends form a nearly circular shape in a free condition in which any external force is not applied. The spring 23 is locked from the outer side into the locking grooves 31 of all of the roller keys 22. When locked in all of the roller keys 22, the spring 23 is in a state that both the ends are separated from each other, and in such a state, it exhibits a spring force biasing all of the roller keys 22 each to the inward recesses 24.
An annular groove 32 is opened in the inner
peripheral surface of the cylindrical portion 12a for containing the spring 23 in such a state as to allow the displacement of the spring 23 due to the movement of the roller keys 22.
The function of the first one-way clutch 15 will be described below. When the outputting member 13 is rotated in the direction where the inward meshing portion 26 of each inward recess 24 meshes with the roller key 22 as shown by an arrow 33 in Fig. 3, the roller key 22 is held between the inward meshing portion 26 of the inward recess
24 and the outward meshing portion 30 of the outward recess
25 in a state that the rotational speed of the outputting
member 13 is less than a preset rotational speed determined
by the spring force, and thereby a power transmission is
performed between the outputting member 13 and the
cylindrical portion 12a of the inputting member 12. The
first one-way clutch thus comes to be in the power
transmission state. Next, when the crank shaft 6, that is,
the cylindrical portion 12a is rotated at a rotational
speed more than that of the outputting member 13, each
roller key 22 is contained in the containing portion 28 of
the outward recess 25 against the spring force of the spring 23, so that the power transmission between the cylindrical portion 12a of the inputting member 12 and the outputting member 13 is cut off.
Referring again to Figs. 1 and 2, the planetary gear mechanism 14 includes the sun gear 35; the ring gear 36 coaxially surrounding the sun gear 35; a plurality of the planetary gears 38 meshing with the sun gear 35 and the ring gear 36; and the planetary carrier 37 rotatably supporting the planetary gears 38. The sun gear 35 is spline-connected to the outer periphery of the leading end of the cylindrical portion 12a of the inputting member 12; the planetory carrier 37 is connected to the outputting member 13; and the ring gear 36 is formed integrally with one end of the cylinder 39.
The fixed shaft 17 is fixed on the transmission case 5 in line with the crank shaft 6, and the rotation control member 16 is disposed in such a manner as to coaxially surround the fixed shaft 17.
Referring to Fig. 4, the second one-way clutch 18 includes an inner clutch 41 spline-connected to the fixed
shaft 17; an outer clutch 42 fixed in the rotation control member 16 by press-fitting or the like in such a manner as to coaxially surround the inner clutch 41; a plurality of roller keys 43 disposed between the inner clutch 41 and the outer clutch 42 in such a manner as to be spaced at intervals in the circumferential direction; and a spring 44 commonly locked with the outer sides of the roller keys 43 .
A plurality of inward recesses 45 are provided in the outer peripheral surface of the inner clutch 41 in such a manner as to be spaced at intervals in the circumferential direction. The inner peripheral surface of the outer clutch 42 is closely opposed to the outer peripheral surface of the inner clutch 41, and a plurality of outward recesses 46 corresponding to the inward recesses 45 are provided in the inner peripheral surface of the outer clutch 42.
The inward recess 45 includes an inward meshing portion 47 capable of meshing with the inner side of the roller key 43; and an inward inclined surface 48 continuous at one end to the inward meshing portion 47 and inclined radially outward as nearing one side (left side in Fig. 4)
of the inner clutch 41 in the circumferential direction. The inward meshing portion 47 is formed in an arcuate shape capable of being substantially brought in press-contact with the outer surface of an inner quarter portion of the roller key 43 .
The outward recess 46 includes a containing portion 49 capable of containing the entire roller key 43; an outward inclined surface 50 continuous at one end to the containing portion 49 and inclined radially inward as nearing one side (left side in Fig. 4) of the inner clutch 41 in the circumferential direction; and an outward meshing portion 51 continuous to the other end of the outward inclined surface 50 for holding the roller key 43 between the inward meshing portion 47 and the same. More "specifically, the containing portion 49 is formed in such a shape to contain the entire roller key 43 for preventing the roller key 43 from being brought in contact with the outer peripheral surface of the inner clutch 41. The outward meshing portion 51 is formed in such an arcuate shape as to hold the roller key 43 between the inward meshing portion 47 and the same.
An annular locking groove 52 is formed in the outer periphery of each of the roller keys 43 at the axial center portion. The spring 44 is formed of a spring wire curved in such a manner that both the ends form a nearly circular shape in a free condition in which any external force is not applied. The spring 44 is locked from the outer side in the locking grooves 52 of all of the roller keys 43 . When locked with all of the roller keys 43 , the spring 44 is in a state that both the ends are separated from each other, and in such a state, it exhibits a spring force biasing all of the roller keys 43 to the inward recesses 45.
An annular groove 53 is opened in the inner peripheral surface of the outer clutch 42 for containing the spring 44 in such a state as to allow the displacement of the spring 44 due to the movement of the roller keys 43 .
The function of the second one-way clutch 18 will be described below. When the outer clutch 42 integrated with the rotation control member 16 is rotated in the direction reversed to the rotational direction of the
inputting member 12, that is, in the direction where the outward meshing portion 51 meshes with each roller key 43 as shown by an arrow 54 in Fig. 4, the roller key 43 is held between the outward meshing portion 51 of the outward recess 46 and the inward meshing portion 47 of the inward recess 45, so that a power is intended to be transmitted from the outer clutch 42, that is, the rotation control member 16 to the inner clutch 41; however, since the inner clutch 41 is spline-connected to the fixed shaft 17, the rotations of the outer clutch 42 and the rotation control member 16 are restrained. On the other hand, when the outer clutch 42 is rotated in the same direction as that of the inputting member 12 as shown by an arrow 55 in Fig. 4, each roller key 22 is contained in the containing portion 49 of the outward recess 46 against the spring force of the spring 44, as a result of -which the outer clutch 42, that is, the rotation control member 16 idles around the fixed shaft 17.
The first centrifugal clutch 19 includes the cylinder 39 integrated at one end with the ring gear 36 and surrounding the rotation control member 16; a plurality of outer clutch plates 57 provided between the rotation
control member 16 and the cylinder 39 in such a manner that the outer peripheries thereof are spline-connected to the cylinder 39; one or a plurality of inner clutch plates 58 alternately arranged between the outer clutch plates 57 in such a manner that the outer peripheries thereof are spline-connected to the rotation control member 16; a pressure receiving plate 59 mounted on the inner surface of the cylinder 39 in such a manner as to face the outer surface of the outermost outer clutch plate 57; a spring 60 compressed between the innermost and the outermost outer clutch plates 57; a plurality of rolling balls 62 rotatably supported by a holding plate 61 facing the inner surface of the innermost outer clutch plate 57 and brought in rolling-contact with the inner surface of the innermost outer clutch plate 57; a pressing plate 63 disposed opposite to the outer clutch plates 57 with-respect to the holding plate 61 and brought in rolling-contact with the rolling balls 62; a cam plate 64 provided integrally with the inputting member 12 in such a manner as to be positioned opposite to the holding plate 61 with respect to the pressing plate 63 and to face the pressing plate 63; and a plurality of centrifugal balls 65 disposed between the cam plate 64 and the pressing plate 63. A plurality of cam
surfaces 64a are provided on the surface, opposite to the pressing plate 63, of the cam plate 64 in such a manner as to be spaced at intervals. The cam surface 64a is inclined in such a manner as to come near the pressing plate 63 as extending radially outward of the cam plate 64 and brought in rolling-contact with the centrifugal balls 65. A stopper ring 83 engaged with the innermost outer clutch plate 57 from the holding plate 61 side, is fitted on the inner surface of the cylinder 39. The set load of the spring 60 is determined by the stopper ring 83.
The function of the first centrifugal clutch 19 will be described below. Each centrifugal ball 64 is applied with a centrifugal force by rotation of the inputting member 12, that is, the cam plate 64, and it moves radially outward of the cam plate 64 along the cam surface 64a in proportion to the centrifugal force, as a result of which the pressing plate 63 presses the innermost outer clutch plate 57 against the spring force of the spring 60. When the pressing force of the pressing plate 63 overcomes the spring force of the spring 60 and allows the outer and inner clutch plates 57, 58 to be friction-engaged with each other, the cylinder 39, that is, the ring
gear 36 is connected to the rotation control member 16. In this case, the spring force of the spring 60 is so determined that the frictional engagement of the centrifugal clutch 19 is started by a pressing force generated at the pressing plate 63 when the rotational speed of the inputting member 12, that is, the cam plate 64 reaches a first preset rotational speed, for example, the rotational speed upon starting a motor-bicycle, and the frictional engagement of the centrifugal clutch 19 is completed when the rotational speed of the inputting member 12 reaches a second preset rotational speed more than the first preset rotational speed.
The second centrifugal clutch 20 includes a first pressure receiving plate 66 radially inward protruding from a portion, of the cylinder 39, near the ring gear 36 on one end side; a second pressure receiving plate 67 disposed at a position separated from the first pressure receiving plate 66 on the cam plate 64 side in such a manner that the outer peripheral portion thereof is spline-connected to the cylinder 39; a plurality of spherical rolling balls 69 rotatably supported by a holding plate 68 disposed between the second pressure receiving plate 67 and the cam plate
64, and brought in rolling-contact with the second receiving plate 67 and the cam plate 64; a spring 70 compressed between the first and second pressure receiving plates 66, 67; a first friction plate 71 facing the first pressure receiving plate 66 for free frictional engagement therewith, and spline-connected at its inner periphery with the cylindrical portion 12a of the inputting member 12; a second friction plate 72 facing the second pressure receiving plate 67 for free frictional engagement therewith, and spline-connected at its inner periphery with the cylindrical portion 12a; and a disc spring 74 provided between the first friction plate 71 and a stop ring 75 mounted on the outer surface of the cylindrical portion 12a at a position separated from the first friction plate 71 on the sun gear 35 side. The outer peripheral portion of the first friction plate 71 is liquid-tightly fitted to the outer peripheral portion of the second friction plate 72, and a liquid chamber 73 is formed between the outer peripheral portions of the first and second friction plates 71, 72. A stopper ring 84 engaged with the second pressure receiving plate 67 from the holding plate 68 side is mounted on the cylinder 39. The set load of the spring 70 is determined by the stopper ring 84.
The function of the second centrifugal clutch 20 will be described below. A lubricating liquid held between both the friction plates 71, 72 is applied with a centrifugal force by rotation of the inputting member 12, that is, the first and second friction plates 71, 72, and it moves to the liquid chamber 73 side, with a result that the pressure in the liquid chamber 73 is increased. The pressure in the liquid chamber 73 acts to separate the friction plates 71, 72 from each other. When such a pressure overcomes the spring force of the disc spring 74 and acts to move the first friction plate 71 to the extent that the first friction plate 71 is friction-engaged with the first pressure receiving plate 66, the second friction plate 72 is also friction-engaged with the second pressure receiving plate 67. As a result, the cylinder 39,- that is, the ring gear 36 is connected to the cylindrical portion 12a, that is, the inputting member 12. In this case, the spring force of the disc spring 74 is so determined that the frictional engagement of the second friction plate 20 is started by a pressing force generated at the first friction plate 71 when the rotational speed of the inputting member 12 reaches a third preset rotational speed
more than the second preset rotational speed of -the first centrifugal clutch 19, and the frictional engagement is completed when the rotational speed of the inputting member 12 reaches a fourth preset rotational speed more than the third preset rotational speed.
Incidentally, a cover 78 is mounted on the cam plate 64 in such a manner that a lubricating sump 77 is formed between the cover 78 and the cam plate 64, and a lubricating liquid passage 79 provided in the transmission case 5 and the fixed shaft 17 is communicated to the lubricating sump 77 . A supply passage 81 is provided in the inputting member 12 for introducing the lubricating liquid in the lubricating sump 77 between the inner peripheral portions of the first and second friction plates 71, 72.
The function of the first embodiment will be described with reference to Fig. 5. When a rotational power is supplied from a kick starter (not shown) to the output member 13 of the first one-way clutch 15 through the output gear 7 as shown by the arrow 33 of Fig. 3, the output member 13 is rotated in the direction where the
inward meshing portion 26 of the inward recess 24 meshes with each roller key 22. At this time, the roller key 22 is held between the outward meshing portion 30 of the outward recess 25 and the inward meshing portion 26 of the inward recess 24 in a state that the rotational speed of the outputting member 13 is less than the preset rotational speed determined by the spring force of the spring 23, so that the power transmission is performed between the outputting member 13 and the cylindrical portion 12a of the inputting member 12 impossible to be relatively rotatable with respect to the crank shaft 6. Namely, the first one way clutch 15 is turned in the power transmission state, and accordingly the power supplied from the kick starter is inputted to the crank shaft 6 and thereby the engine is started. On the other hand, the sun gear 35 and the planetary carrier 37 in the planetary gear mechanism 14 are rotated in a state being integrated with each other along with the power transmission from the outputting member 13 to the inputting member 12 through the first one-way clutch 15. Thus, the ring gear 36 is also rotated in the same direction as the rotational direction of the inputting member 12 together with the sun gear 35 and the planetary carrier 37. However, since the rotational speed of the
inputting member 12 is less than the first preset rotational speed, the first centrifugal clutch 19 is in the power cut-off state, as a result of which the ring gear 36 idles .
When the engine is started and the crank shaft 6, that is, the cylindrical portion 12a of the inputting member 12 is started to be rotated at a rotational speed more than that of the outputting member 13, each roller key 22 in the first one-way clutch 15 is contained in the containing portion 28 of the outward recess 25 against the spring force of the spring 23 . The power transmission by the first one-way clutch 15 is thus cut off, and thereby the rotational power of the crank shaft 6 is not transmitted to the outputting member 13 .
When the engine speed is increased up to a first preset rotational speed N1 more than the idling rotational speed, the ring gear 36, that is, the cylinder 39 is rotated in the direction reversed to the rotational direction of the inputting member 12 along with the rotation of the sun gear 35 together with the inputting member 12, and the engagement of the first centrifugal
clutch 19 is started. As a result, a rotational power in the direction reversed to the rotational direction of the inputting member 12 , which corresponds to the engagement force of the centrifugal clutch 19, is transmitted to the rotation control member 16. However, since the rotation of the rotation control member 16 in the direction reversed to the rotational direction of the inputting member 12 is restrained by the second one-way clutch 18, the rotation of the cylinder 39, that is, the ring gear 36 is braked. In other words, the ring gear 36 is braked on the basis of the engagement force of the first centrifugal clutch 19. Thus, the planetary carrier 37 in the planetary gear mechanism 14 is rotated in the same direction as that of the sun gear 35, that is, the inputting member 12 in accordance with the rotational speed of the ring gear 36 at a transmission gear ratio variable based on a change in the engagement force of the first centrifugal clutch 19 depending on a change in the rotational speed of the inputting member 12 . The transmitting torque between the inputting member 12 and the outputting member 13 is thus increased linearly with the rotational speed of the inputting member 12 .
When the rotational speed of the inputting member

12 is further increased up to a second preset rotational speed N2, the frictional engagement of the first centrifugal clutch 19 is maximized, and thereby the rotation of the ring gear 36 is perfectly stopped. As a result, the rotational power is transmitted from the inputting member 12 to the outputting member 13 at a constant transmission gear ratio determined by the planetary gear mechanism 14. In other words, a power is transmitted to the outputting member 13 in proportion to the engine speed. This mode is used for the low speed running of the motor-bicycle.
When the rotational speed of the inputting member 12 reaches a third preset rotational speed N3 more than the second preset rotational speed N2, the engagement of the second centrifugal clutch 20 is started, and the ring gear 36 is connected to the inputting member 12 by the engagement force of the second centrifugal clutch 20 and it is rotated in the same direction as the rotational direction of the inputting member 12. Namely, the rotational power is transmitted to the outputting member 13 at a transmission gear ratio variable based on a change in the engagement force of the second centrifugal clutch 20
depending on the rotational speed of the inputting member 12. In this case, the first centrifugal clutch 19 is also in the engagement state; however, since the rotation control member 16 is allowed to be rotated in the same direction as the rotational direction of the inputting member 12, the ring gear 36 is allowed to be rotated in the same direction as the rotational direction of the inputting member 12 .
When the rotational speed of the inputting member 12 reaches a fourth preset rotational seed N4 more than the third preset rotational speed N3, the frictional engagement of the second centrifugal clutch 20 is completed, so that the ring gear 36 and the cylinder 39 are rotated in the same direction as the rotational direction of the inputting member 12 in a state being integrated therewith. The inputting member 12 and the outputting member 13 are thus rotated in a state being integrated with each other through the planetary gear mechanism 14 along with the integral rotation of the sun gear 34, ring gear 36 and inputting member 12. This mode is used for the high speed running of the motor-bicycle.
The load characteristic of the disc spring 74 of the second centrifugal clutch 20 is shown in Fig. 6. When the maximum load is taken as the set load, the spring load of the disc spring 74 is lower than the set load when the frictional engagement of the second centrifugal clutch 20 is completed. Accordingly, the high speed running state is continued until the rotational speed becomes a value less than the fourth preset rotational speed N4 upon deceleration, as shown by a broken line in Fig. 5.
As described above, according to the continuously variable transmission of the present invention, it is possible to make small in size by arranging the inputting member 12 and the outputting member 13 on the same axial line, and to enhance the durability as compared with the related art belt-type continuously variable transmission. In addition, an ordinary transmission efficiency on the low speed side can be obtained by the planetary gear mechanism 14 and a high transmission efficiency on the high speed side can be obtained by direct coupling between the inputting member 12 and the outputting member 13.
Fig. 7 shows a second embodiment, wherein parts corresponding to those in the first embodiment are indicated by the same characters.
A second centrifugal clutch 20 provided between an inputting member 12 and a ring gear 36 includes a first pressure receiving plate 66 radially outward protruding from a cylinder 39; a second pressure receiving plate 67 spline-connected at its outer periphery with the cylinder 39; a plurality of spherical rolling balls 69 rotatably supported by a holding plate 68 and brought in rolling-contact with the second pressure receiving plate 67 and a cam plate 64; a spring 70 compressed between both the pressure receiving plates 66, 67; a first friction plate 71 facing the first pressure receiving plate 66; and a second friction plate 72' facing the second pressure receiving plate 67; and a disc spring 74 exhibiting a spring force in the direction of moving the first friction plate 71 to the second friction plate 72 ' .
The inner peripheral portion of the second friction plate 72' is spline-connected to the outer periphery of a
cylindrical portion 12a of the inputting member 12. The inner peripheral portion of the first friction plate 71 is spline-connected to the inner peripheral portion of the second friction plate 72 . The outer peripheral portion of the first friction portion 71 is liquid-tightly fitted to the outer peripheral portion of the second friction plate 72. A liquid chamber 73 is formed between the outer peripheral portions of the first and second friction plates 71, 72. A stop ring 75 is fitted on the outer surface of the inner peripheral portion of the second friction plate 72' and the disc spring 74 is provided between the stop ring 75 and the first friction plate 71.
The second embodiment is effective to assemble the continuously variable transmission as a whole, because the first friction plate 71, second friction plate 72', disc spring 74, and the stop ring 74 can be previously assembled as a unit. This makes it possible to improve the assembling efficiency.
While the embodiments of the present invention have been described, such description is for illustrative purposes only, and it is to be understood that many changes
in design may be made without departing from the spirit or scope of the claims.

[Effect of the Invention]
As described above, the continuously variable transmission of the present invention includes: an inputting member; an outputting member rotatable around the same axial line as that of the inputting member; a planetary gear mechanism including a sun gear connected to the inputting member, a ring gear, planetary gears meshing with the sun gear and the ring gear, and a planetary carrier rotatably supporting the planetary gears and connected to the outputting member; a rotation control member having the same rotational axial line as that of the inputting member; a one-way clutch, provided between the rotation control member and a fixed member, for restraining the rotation of the rotation control member in the direction reversed to the rotational direction of the inputting member and permitting the rotation of the rotation control member in the same direction as the rotational direction of the inputting member; a first centrifugal clutch, provided between the ring gear and the rotation control member, for starting the engagement
thereof when the rotational speed of the inputting member reaches a first preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a second preset rotational speed larger than the first preset rotational speed; and a second centrifugal clutch, provided between the inputting member and the ring gear, for starting the engagement thereof when the rotational speed of the inputting member reaches a third preset rotational speed larger than the second preset rotational speed and completing the engagement when the rotational speed of the inputting member reaches a fourth preset rotational speed larger than the third preset rotational speed. Such a continuously variable transmission is effective to obtain a compact structure in which an inputting member and an outputting member are arranged on the same axial line, to enhance the durability as compared with the related art belt-type continuously variable transmission, and to obtain a high transmission efficiency.

We Claim:
1. A continuously variable transmission apparatus comprising: an inputting member (12);
an outputting member (13) rotatable around the same axial line as that of said inputting member (12);
a planetary gear mechanism (14) having a sun gear (35) connected to said inputting member (12); a ring gear (36); planetary gears (38) meshing with said sun gear (35) and said ring gear (36); and a planetary carrier (37) rotatably supporting said planetary gears (38) and connected to said outputting member (13);
a rotation control member (16) having the same rotational axial line as that of said inputting member (12);
a one-way clutch (18), provided between said rotation control member (16) and a fixed member (17), for restraining the rotation of said rotation control member (16) in the direction reversed to the rotational direction of said inputting member (12);
a first centrifugal clutch (19), provided between said ring gear (36) and said rotation control member (16) for starting the engagement thereof; and
a second centrifugal clutch (20, 20'), provided between said inputting member (12) and said ring gear (36), for starting the engagement thereof.
2. A continuously variable transmission apparatus substantially as hereinbefore described with reference to and as illustrated in the foregoing description and accompanying drawings.

Documents:

1017-del-1996-abstract.pdf

1017-del-1996-claims.pdf

1017-del-1996-correspondence-others.pdf

1017-del-1996-correspondence-po.pdf

1017-del-1996-description (complete).pdf

1017-del-1996-drawings.pdf

1017-del-1996-form-13.pdf

1017-del-1996-form-19.pdf

1017-del-1996-form-2.pdf

1017-del-1996-form-3.pdf

1017-del-1996-form-4.pdf

1017-del-1996-form-6.pdf

1017-del-1996-gpa.pdf

1017-del-1996-petition-138.pdf

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Patent Number

222198

Indian Patent Application Number

1017/DEL/1996

PG Journal Number

33/2008

Publication Date

15-Aug-2008

Grant Date

28-Jul-2008

Date of Filing

15-May-1996

Name of Patentee

HONDA GIKEN KOGYO KABUSHIKI KAISHA

Applicant Address

1-1, MINAMIAOYAMA 2-CHOME, MINATO-KU, TOKYO, JAPAN.

Inventors:

#	Inventor's Name	Inventor's Address
1	TAKANORI ONDA	C/O KABUSHIKI KAISHA HONDA GIJUTSU KENYUSHO. OF 4-1, CHUO 1-CHOME, WAKO-SHI, SAITAMA, JAPAN

PCT International Classification Number

F16H 39/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	HEI-7-122517	1995-05-22	Japan