Continuously variable transmission

Abstract

To suppress vibration of a power transmission component.SOLUTION: A continuously variable transmission includes a power transmission component which is wound around a primary pulley and a secondary pulley. The continuously variable transmission includes a guide rail which is arranged in a straight line section of the power transmission component separated from the primary pulley and the secondary pulley. The guide rail includes a first rail end which comes into contact with a first fixed sheave and a first movable sheave of the primary pulley, and a second rail end which comes into contact with a second fixed sheave and a second movable sheave of the secondary pulley.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present disclosure relates to a continuously variable transmission.

Background Art

[0002] A continuously variable transmission has a primary pulley provided on an input shaft and a secondary pulley provided on an output shaft. Also, a chain or a belt is wound around the primary pulley and the secondary pulley as a power transmission component. Further, the continuously variable transmission has a stabilizer for suppressing chain vibration and a guide rail for suppressing belt vibration (see Patent Documents 1 and 2). Note that an engine is also provided with a chain guide for suppressing the vibration of a timing chain (see Patent Document 3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in order to improve the power transmission efficiency of a continuously variable transmission, further suppression of vibration of a chain or a belt, that is, further suppression of vibration of a power transmission component is required.

Means for Solving the Problems

[0005] According to the present disclosure, a continuously variable transmission has a primary pulley including a first fixed sheave fixed to an input shaft and a first movable sheave attached to be axially movable relative to the input shaft. The continuously variable transmission has a secondary pulley including a second fixed sheave fixed to an output shaft and a second movable sheave attached to be axially movable relative to the output shaft. The continuously variable transmission has a power transmission component wound around the primary pulley and the secondary pulley to transmit power from the primary pulley to the secondary pulley. The continuously variable transmission has a guide rail disposed in a straight section of the power transmission component away from the primary pulley and the secondary pulley. The guide rail includes a first rail end in contact with the first fixed sheave and the first movable sheave, and a second rail end in contact with the second fixed sheave and the second movable sheave.

Advantages of the Invention

[0006] According to the present disclosure, vibration of the power transmission component can be suppressed by the guide rail.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8A

Figure 8B

Figure 8C

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Mode for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, the same or substantially the same components and elements are denoted by the same reference numerals, and repeated descriptions are omitted.

[0009] <Embodiment 1> <Power Unit> FIG. 1 is a diagram showing an example of a vehicle 11 equipped with a continuously variable transmission 10 according to an embodiment of the present disclosure. As shown in FIG. 1, the vehicle 11 has a power unit 13 including an engine 12 and a continuously variable transmission 10. The rear wheel output shaft 14 of the power unit 13 is connected to the rear wheels 17 via a propeller shaft 15 and a rear differential mechanism 16. Further, the power unit 13 includes a front differential mechanism 18, and the front differential mechanism 18 is connected to the front wheels 19. Note that the illustrated power unit 13 is a power unit for all-wheel drive, but the present disclosure is not limited thereto, and it may be a power unit for front-wheel drive or rear-wheel drive.

[0010] <Continuously variable transmission> FIG. 2 is a diagram showing an example of the continuously variable transmission 10 included in the power unit 13. As shown in FIG. 2, a torque converter 21, a forward / reverse switching mechanism 22, a transmission mechanism 23, and a transfer clutch 24 are housed in a housing 20 of the continuously variable transmission 10. The transmission mechanism 23 has a primary shaft (input shaft) 31 and a secondary shaft (output shaft) 32 arranged in parallel with the primary shaft 31. The primary shaft 31 is connected to the engine 12 via the forward / reverse switching mechanism 22 and the torque converter 21. The secondary shaft 32 is connected to the front wheels 19 via a gear train 33, a front wheel output shaft 34, and a front differential mechanism 18. Further, the front wheel output shaft 34 is connected to the rear wheel output shaft 14 via a gear train 35 and a transfer clutch 24. Furthermore, an oil pump 38 is connected to a pump shell 36 of the torque converter 21 via a chain mechanism 37, and a valve unit 39, which is a hydraulic adjustment device, is connected to the oil pump 38.

[0011] FIG. 3 is a diagram showing an example of the transmission mechanism 23 provided in the continuously variable transmission 10. Note that in FIG. 3, the transmission mechanism 23 shown in FIG. 2 is shown with its orientation changed. As shown in FIG. 3, the transmission mechanism 23 of the continuously variable transmission 10 includes a primary pulley 40 provided on the primary shaft 31, a secondary pulley 50 provided on the secondary shaft 32, and a chain (power transmission component) 60 wound around the primary pulley 40 and the secondary pulley 50.

[0012] The primary pulley 40 has a primary fixed sheave (first fixed sheave) 41 fixed to the primary shaft 31 and a primary movable sheave (first movable sheave) 42 attached to the primary shaft 31 so as to be axially movable relative to the primary shaft 31. The secondary pulley 50 has a secondary fixed sheave (second fixed sheave) 51 fixed to the secondary shaft 32 and a secondary movable sheave (second movable sheave) 52 attached to the secondary shaft 32 so as to be axially movable relative to the secondary shaft 32. The primary movable sheave 42 is attached to the primary shaft 31 via a ball spline, and the secondary movable sheave 52 is attached to the secondary shaft 32 via a ball spline.

[0013] A drum 43 fixed to the primary shaft 31 is disposed on the back side of the primary movable sheave 42. A primary oil chamber 44 is defined between the drum 43 and the primary movable sheave 42, and the valve unit 39 is connected to the primary oil chamber 44 via an oil passage 45 in the primary shaft 31. A disk 53 fixed to the secondary shaft 32 is disposed on the back side of the secondary movable sheave 52. A secondary oil chamber 54 is defined between the disk 53 and the secondary movable sheave 52, and the valve unit 39 is connected to the secondary oil chamber 54 via an oil passage 55 in the secondary shaft 32. By controlling the hydraulic pressures of the primary oil chamber 44 and the secondary oil chamber 54 by the valve unit 39, the movable sheaves 42 and 52 of both can be moved to control the groove widths of the pulleys 40 and 50.

[0014] Here, FIG. 4 is a cross-sectional view showing the transmission mechanism 23 when the continuously variable transmission 10 is shifted to the low side, and FIG. 5 is a cross-sectional view showing the transmission mechanism 23 when the continuously variable transmission 10 is shifted to the high side. As shown in FIG. 4, by widening the groove width of the primary pulley 40, the winding diameter of the chain 60 around the primary pulley 40 is reduced, and the winding diameter of the chain 60 around the secondary pulley 50 is increased. Thereby, the transmission ratio of the continuously variable transmission 10 can be controlled to the low side. On the other hand, as shown in FIG. 5, by narrowing the groove width of the primary pulley 40, the winding diameter of the chain 60 around the primary pulley 40 is increased, and the winding diameter of the chain 60 around the secondary pulley 50 is reduced. Thereby, the transmission ratio of the continuously variable transmission 10 can be controlled to the high side. Thus, by controlling the groove widths of both pulleys to change the winding diameter of the chain 60, the transmission ratio of the continuously variable transmission 10 can be steplessly controlled.

[0015] Note that the dashed-dotted line CL1 shown in FIG. 3, the dashed-dotted line CL2 shown in FIG. 4, and the dashed-dotted line CL3 shown in FIG. 5 all indicate the center position in the width direction of the chain 60. That is, as shown in FIGS. 3 and 4, when the groove width of the primary pulley 40 is widened to control the transmission ratio to the low side, the chain 60 moves parallel in the direction approaching the primary movable sheave 42. On the other hand, as shown in FIGS. 3 and 5, when the groove width of the primary pulley 40 is narrowed to control the transmission ratio to the high side, the chain 60 moves parallel in the direction approaching the primary fixed sheave 41.

[0016] <Guide rail structure> FIG. 6 is a cross-sectional view showing the transmission mechanism 23 along the line VI-VI of FIG. 3. Note that the arrow D1 shown in FIG. 6 indicates the rotational direction of the primary pulley 40 during forward travel. Further, FIG. 7 is a plan view showing the transmission mechanism 23 along the line VII-VII of FIG. 6. Furthermore, FIG. 8A is a cross-sectional view showing the guide rail 70 along the line VIII-VIII of FIG. 6. Also, FIGS. 8B and 8C are cross-sectional views showing the guide rail 70 at the same part as FIG. 8A.

[0017] As shown in FIG. 6, on the chain 60, an arc section Sa1 that contacts the primary pulley 40, an arc section Sa2 that contacts the secondary pulley 50, and a pair of straight sections Sb1, Sb2 located between the arc section Sa1 and the arc section Sa2 are set. In other words, the straight sections Sb1, Sb2 of the chain 60 are the sections where the chain 60 is separated from the primary pulley 40 and the secondary pulley 50.

[0018] As shown in FIGS. 6 and 7, a guide rail 70 that swings following the chain 60 is arranged on the straight section Sb1 of the chain 60. A long guide hole 72 is formed in the central portion 71 of the guide rail 70, and a rod 73 fixed to the housing 20 is inserted into this guide hole 72. That is, the guide rail 70 is swingably supported by the rod 73 attached to the housing 20. Further, the guide rail 70 has an outer plate 74 facing the outer peripheral surface of the chain 60, an inner plate 75 facing the inner peripheral surface of the chain 60, and a pair of connecting portions 76, 77 that connect the outer plate 74 and the inner plate 75. By suppressing the runout of the chain 60 with this guide rail 70, the string vibration of the chain 60 can be suppressed.

[0019] The guide rail 70 has a first rail end 81 that contacts the primary pulley 40 and a second rail end 82 that contacts the secondary pulley 50. That is, the guide rail 70 has a first rail end 81 that contacts the primary fixed sheave 41 and the primary movable sheave 42, and a second rail end 82 that contacts the secondary fixed sheave 51 and the secondary movable sheave 52. As shown in FIG. 7, the first rail end 81 has a contact mechanism 84 provided with a ball (first contact portion) 83 that contacts the primary fixed sheave 41 and a contact mechanism 88 provided with a ball (second contact portion) 87 that contacts the primary movable sheave 42. Further, the second rail end 82 has a contact mechanism 92 provided with a ball (third contact portion) 91 that contacts the secondary fixed sheave 51 and a contact mechanism 94 provided with a ball (fourth contact portion) 93 that contacts the secondary movable sheave 52.

[0020] As shown in FIG. 8A, the contact mechanism 84 of the guide rail 70 has a holder 85 that rotatably holds the balls 83, and a spring 86 that biases the holder 85 in the width direction D2 of the guide rail 70. Similarly, the contact mechanism 88 of the guide rail 70 has a holder 89 that rotatably holds the balls 87, and a spring 90 that biases the holder 89 in the width direction D2 of the guide rail 70. As shown in FIG. 8B, when the distance between the primary fixed sheave 41 and the primary movable sheave 42 increases, the ball 83 is pushed out toward the primary fixed sheave 41, and the ball 87 is pushed out toward the primary movable sheave 42. On the other hand, as shown in FIG. 8C, when the distance between the primary fixed sheave 41 and the primary movable sheave 42 decreases, the ball 83 is pushed back by the primary fixed sheave 41, and the ball 87 is pushed back by the primary movable sheave 42.

[0021] In this way, the balls 83 and 87 are movably attached in the width direction D2 of the guide rail 70 to the first rail end portion 81 of the guide rail 70. Also, the contact mechanisms 92 and 94 provided at the second rail end portion 82 have the same structure as the contact mechanisms 84 and 88 provided at the first rail end portion 81. That is, the balls 91 and 93 are movably attached in the width direction D2 of the guide rail 70 to the second rail end portion 82 of the guide rail 70. As shown in FIG. 8A, the chain 60 has a plurality of link plates 61 and a plurality of rocker pins 62 that connect the link plates 61 to each other. Also, the end faces of the rocker pins 62 contact the primary pulley 40 and the secondary pulley 50 to transmit torque.

[0022] As shown in FIGS. 6 and 7, the continuously variable transmission 10 includes a first spring unit (first biasing unit) 100 that biases the guide rail 70, and a second spring unit (second biasing unit) 110 that biases the guide rail 70. The first spring unit 100 has a base end portion (first base end portion) 103 provided with a roller 102 housed in a roller groove 101 of the housing 20, an expansion and contraction portion 105 attached to the base end portion 103 and housing a spring 104, and a ball (first tip portion) 106 rotatably attached to the tip of the expansion and contraction portion 105. Similarly, the second spring unit 110 has a base end portion (second base end portion) 113 provided with a roller 112 housed in a roller groove 111 of the housing 20, an expansion and contraction portion 115 attached to the base end portion 113 and housing a spring 114, and a ball (second tip portion) 116 rotatably attached to the tip of the expansion and contraction portion 115.

[0023] A guide groove 107 with which the ball 106 of the first spring unit 100 contacts is formed in the first rail end portion 81 of the guide rail 70, and a guide groove 117 with which the ball 116 of the second spring unit 110 contacts is formed in the second rail end portion 82 of the guide rail 70. That is, the ball 106 of the first spring unit 100 contacts the guide groove 107 on the side of the first rail end portion 81 rather than the central portion 71. That is, the ball 106 of the first spring unit 100 contacts on the side of the first rail end portion 81 rather than the center in the longitudinal direction of the guide rail 70. Further, the ball 116 of the second spring unit 110 contacts the guide groove 117 on the side of the second rail end portion 82 rather than the central portion 71. That is, the ball 116 of the second spring unit 110 contacts on the side of the second rail end portion 82 rather than the center in the longitudinal direction of the guide rail 70. Furthermore, the roller grooves 101, 111 of the housing 20 are formed to extend parallel to the primary shaft 31. That is, the spring units 100, 110 attached to the housing 20 are movable in the axial direction of the primary shaft 31, that is, in the width direction D2 of the chain 60 and the guide rail 70.

[0024] <Guide Rail Operation> Next, the operation of the guide rail 70 accompanying the speed change of the continuously variable transmission 10 will be described. FIG. 9 is a cross-sectional view showing the speed change mechanism 23 along the line IX-IX of FIG. 4, and FIG. 10 is a cross-sectional view showing the speed change mechanism 23 along the line X-X of FIG. 5. Note that the virtual plane P1 shown in FIGS. 9 and 10 is a plane including the axial centers of the primary shaft 31 and the secondary shaft 32.

[0025] As shown in FIG. 9, when the speed ratio of the continuously variable transmission 10 is controlled to the low side, the winding diameter of the chain 60 around the primary pulley 40 is reduced, and the winding diameter of the chain 60 around the secondary pulley 50 is increased. At this time, although the straight section Sb1 of the chain 60 is inclined with respect to the virtual plane P1, the guide rail 70 is swingably supported by the rod 73, and the guide rail 70 is biased by the spring units 100 and 110. Thereby, the guide rail 70 can be inclined according to the inclination angle of the chain 60, and the guide rail 70 can appropriately follow the chain 60.

[0026] Moreover, since the first rail end 81 is biased by the first spring unit 100, the first rail end 81 can be appropriately brought into contact with the tapered surfaces 41a and 42a of the primary fixed sheave 41 and the primary movable sheave 42. Also, since the second rail end 82 is biased by the second spring unit 110, the second rail end 82 can be appropriately brought into contact with the tapered surfaces 51a and 52a of the secondary fixed sheave 51 and the secondary movable sheave 52. Thereby, the position and posture of the guide rail 70 can be stabilized, so that the string vibration of the chain 60 can be effectively suppressed by the guide rail 70.

[0027] Further, as shown in FIGS. 8A, 8B, and 8C, balls 83 and 87 are attached to the first rail end 81 of the guide rail 70 so as to be movable in the width direction D2 of the guide rail 70. Similarly, balls 91 and 93 are attached to the second rail end 82 of the guide rail 70 so as to be movable in the width direction D2 of the guide rail 70. Thereby, the first rail end 81 can be appropriately brought into contact with the tapered surfaces 41a and 42a of the primary pulley 40, and the second rail end 82 can be appropriately brought into contact with the tapered surfaces 51a and 52a of the secondary pulley 50.

[0028] For example, in the example shown in FIG. 6, the radial dimension difference between the broken-line circle that is the contact position of the chain 60 with respect to the primary pulley 40 and the dashed-dotted line circle that is the contact position of the first rail end 81 with respect to the primary pulley 40 is "Da6". Further, in the example shown in FIG. 9, the radial dimension difference between the broken-line circle that is the contact position of the chain 60 with respect to the primary pulley 40 and the dashed-dotted line circle that is the contact position of the first rail end 81 with respect to the primary pulley 40 is "Da9". Furthermore, in the example shown in FIG. 10, the radial dimension difference between the broken-line circle that is the contact position of the chain 60 with respect to the primary pulley 40 and the dashed-dotted line circle that is the contact position of the first rail end 81 with respect to the primary pulley 40 is "Da10".

[0029] Since these dimensional differences Da6, Da9, and Da10 are different from each other, the groove width of the primary pulley 40 at the contact position of the first rail end 81 will increase or decrease according to the transmission ratio of the continuously variable transmission 10. That is, in order to keep the first rail end 81 in contact with the primary pulley 40, it is necessary to change the width dimension of the first rail end 81 according to the transmission ratio. Therefore, balls 83 and 87 are attached to the first rail end 81 so as to be movable in the width direction of the guide rail 70. Thereby, the first rail end 81 can be appropriately brought into contact with the tapered surfaces 41a and 42a of the primary pulley 40.

[0030] Similarly, in the example shown in FIG. 6, the radial dimension difference between the dashed circle, which is the contact position of the chain 60 with respect to the secondary pulley 50, and the chain-dotted circle, which is the contact position of the second rail end 82 with respect to the secondary pulley 50, is "Db6". Also, in the example shown in FIG. 9, the radial dimension difference between the dashed circle, which is the contact position of the chain 60 with respect to the secondary pulley 50, and the chain-dotted circle, which is the contact position of the second rail end 82 with respect to the secondary pulley 50, is "Db9". Further, in the example shown in FIG. 10, the radial dimension difference between the dashed circle, which is the contact position of the chain 60 with respect to the secondary pulley 50, and the chain-dotted circle, which is the contact position of the second rail end 82 with respect to the secondary pulley 50, is "Db10".

[0031] Since these dimensional differences Db6, Db9, and Db10 are different from each other, the groove width of the secondary pulley 50 at the contact position of the second rail end 82 will increase or decrease according to the transmission ratio of the continuously variable transmission 10. That is, in order to keep the second rail end 82 in contact with the secondary pulley 50, it is necessary to change the width dimension of the second rail end 82 according to the transmission ratio. Therefore, balls 91 and 93 are attached to the second rail end 82 so as to be movable in the width direction of the guide rail 70. Thereby, the second rail end 82 can be appropriately brought into contact with the tapered surfaces 51a and 52a of the secondary pulley 50.

[0032] As shown in FIG. 7, a guide groove 107 with which the ball 106 of the first spring unit 100 comes into contact is formed at the first rail end 81 of the guide rail 70, and a guide groove 117 with which the ball 116 of the second spring unit 110 comes into contact is formed at the second rail end 82 of the guide rail 70. Thereby, the contact positions of the balls 106 and 116 with respect to the guide rail 70 can be changed, and the guide rail 70 can appropriately follow the chain 60. Further, the roller grooves 101 and 111 of the housing 20 are formed to extend parallel to the primary shaft 31, and the spring units 100 and 110 can be moved in the width direction D2 of the chain 60 and the guide rail 70. Thereby, even when the guide rail 70 is moved in the width direction of the chain 60 together with the chain 60, the guide rail 70 can appropriately follow the chain 60.

[0033] <Embodiment 2> In the example shown in FIG. 6, a margin is provided in the length dimension of the outer plate 74 with respect to the straight section Sb1 of the chain 60, but the present invention is not limited to this, and an outer plate longer than the outer plate 74 shown in FIG. 6 may be used.

[0034] FIG. 11 is a cross-sectional view showing an example of a speed change mechanism 121 provided in a continuously variable transmission 120 according to another embodiment of the present disclosure. Parts similar to those in FIG. 6 are shown in FIG. 11. FIG. 12 is a plan view showing the speed change mechanism 121 along the line XII-XII in FIG. 11. Further, FIG. 13 is a cross-sectional view showing the speed change mechanism 121 when the continuously variable transmission 120 is shifted to the low side, and FIG. 14 is a cross-sectional view showing the speed change mechanism 121 when the continuously variable transmission 120 is shifted to the high side. In FIGS. 11 to 14, parts and sites similar to the parts and sites shown in FIGS. 6 and 7 are denoted by the same reference numerals, and the description thereof is omitted.

[0035] As shown in FIGS. 11 and 12, a guide rail 122 that swings following the chain 60 is disposed in a straight section Sb1 of the chain 60. A guide hole 124 having an arcuate cross-sectional shape is formed in a central portion 123 of the guide rail 122, and a rod 73 fixed to the housing 20 is inserted into the guide hole 124. That is, the guide rail 122 is swingably supported by the rod 73 attached to the housing 20. Further, the guide rail 122 has an outer plate 125 facing the outer peripheral surface of the chain 60, an inner plate 75 facing the inner peripheral surface of the chain 60, and a pair of connecting portions 76, 77 connecting the outer plate 125 and the inner plate 75. By suppressing the runout of the chain 60 by the guide rail 122, the string vibration of the chain 60 can be suppressed.

[0036] The guide rail 122 has a first rail end 131 that contacts the primary pulley 40 and a second rail end 132 that contacts the secondary pulley 50. That is, the guide rail 122 has a first rail end 131 that contacts the primary fixed sheave 41 and the primary movable sheave 42, and a second rail end 132 that contacts the secondary fixed sheave 51 and the secondary movable sheave 52. As shown in FIG. 12, the first rail end 131 has a contact mechanism 84 provided with a ball 83 that contacts the primary fixed sheave 41 and a contact mechanism 88 provided with a ball 87 that contacts the primary movable sheave 42. Similarly, the second rail end 132 has a contact mechanism 92 provided with a ball 91 that contacts the secondary fixed sheave 51 and a contact mechanism 94 provided with a ball 93 that contacts the secondary movable sheave 52.

[0037] The length dimension of the outer plate 125 that constitutes the guide rail 122 is set to be close to the length dimension of the straight section Sb1 of the chain 60 in the low state shown in Fig. 13 and the high state shown in Fig. 14. In this way, by increasing the length dimension of the outer plate 125, it is possible to suppress runout in almost all of the straight section Sb1 of the chain 60, so that the string vibration of the chain 60 can be effectively suppressed.

[0038] Moreover, as shown in Figs. 11, 13, and 14, the radial dimension differences Da11, Da13, and Da14 between the broken-line circle that is the contact position of the chain 60 with respect to the primary pulley 40 and the chain-dotted circle that is the contact position of the first rail end 131 with respect to the primary pulley 40 can be made closer to each other. Similarly, the radial dimension differences Db11, Db13, and Db14 between the broken-line circle that is the contact position of the chain 60 with respect to the secondary pulley 50 and the chain-dotted circle that is the contact position of the second rail end 132 with respect to the secondary pulley 50 can be made closer to each other.

[0039] That is, the amount of change in the groove width of the primary pulley 40 at the contact position of the first rail end 131 can be reduced, and the amount of change in the groove width of the secondary pulley 50 at the contact position of the second rail end 132 can be reduced. As a result, the amount of movement of the balls 83 and 87 attached to the first rail end 131 can be reduced, and the amount of movement of the balls 91 and 93 attached to the second rail end 132 can be reduced, so that the configuration of the contact mechanisms 84, 88, 92, and 94 can be simplified.

[0040] Note that, as shown in Figs. 11 to 14, when the length dimension of the outer plate 125 is increased, the guide rail 122 will swing with a larger stroke than the guide rail 70 shown in Fig. 6. For this reason, an arc-shaped guide hole 124 that is longer than the guide hole 72 is formed in the outer plate 125, and guide grooves 133 and 134 that are longer than the guide grooves 107 and 117 are formed. Thereby, the guide rail 122 can be appropriately made to follow the chain 60.

[0041] As shown in FIG. 12, the guide rail 122 has a spring 135 that biases the rod 73 toward the first rail end 131 and a spring 136 that biases the rod 73 toward the second rail end 132. Thereby, as shown in FIG. 11, when the gear ratio of the continuously variable transmission 120 is controlled toward "1", the guide rail 122 can be appropriately returned to the neutral position. In the illustrated example, two springs 135 and 136 are attached, but the present invention is not limited thereto, and one spring may be attached to the guide rail 122 so as to bias the rod 73 in the thickness direction of the guide rail 122.

[0042] <Other Embodiments> The present disclosure is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist thereof. In the above description, as the power transmission component, a chain 60 including a link plate 61 and a rocker pin 62 is used, but the present invention is not limited thereto, and a belt including an element and a band may be used as the power transmission component. Further, in the above description, as the contact portions, rolling contact balls 83, 87, 91, 93 are attached to the guide rails 70, 122, but the present invention is not limited thereto. For example, as the contact portions, rolling contact rollers or sliding contact sliders may be attached to the guide rails 70, 122.

[0043] In the above description, the guide rails 70, 122 are arranged with respect to the straight section Sb1 of the chain 60, but the present invention is not limited thereto, and the guide rails 70, 122 may be arranged with respect to the straight section Sb2, or the guide rails 70, 122 may be arranged with respect to both straight sections Sb1 and Sb2. Further, with respect to one of the straight sections Sb1 and Sb2, a guide rail 70, 122 that contacts the pulleys 40, 50 may be arranged, and with respect to the other of the straight sections Sb1 and Sb2, a guide rail that does not contact the pulleys 40, 50 may be arranged.

[0044] In addition, when the power transmission component is the chain 60, since torque is transmitted in the pulling direction by the chain 60, it is desirable to arrange the guide rails 70 and 122 with respect to the straight section Sb1 on the pushing-out side from the primary pulley 40 toward the secondary pulley 50. Further, when the power transmission component is a belt, since torque is transmitted in the pushing-out direction by the belt, it is desirable to arrange the guide rails 70 and 122 with respect to the straight section Sb2 on the pulling-in side from the secondary pulley 50 toward the primary pulley 40.

[0045] In the above description, the rod 73 is fixed to the housing 20 and the guide rails 70 and 122 are swingably attached to the rod 73, but it is not limited thereto. For example, the rod 73 may be fixed to the guide rails 70 and 122 and the rod 73 may be movably attached to the housing 20. Further, the inner plate 75 constituting the guide rails 70 and 122 has a shape that does not interfere with both pulleys 40 and 50 even when the speed ratio is controlled to the low side or the high side.

Explanation of Signs

[0046] 10… continuously variable transmission, 31… primary shaft (input shaft), 32… secondary shaft (output shaft), 40… primary pulley, 41… primary fixed sheave (first fixed sheave), 42… primary movable sheave (first movable sheave), 50… secondary pulley, 51… secondary fixed sheave (second fixed sheave), 52… secondary movable sheave (second movable sheave), 60… chain (power transmission component), 70… guide rail, 81… first rail end, 82… second rail end, 83… ball (first contact portion), 87… ball (second contact portion), 91… ball (third contact portion), 93… ball (fourth contact portion), 100… first spring unit (first biasing unit), 103… base end portion (first base end portion), 106… ball (first tip end portion), 110… second spring unit (second biasing unit), 113… base end portion (second base end portion), 116… ball (second tip end portion), 120… continuously variable transmission, 122… guide rail, 131… first rail end, 132… second rail end, Sb1, Sb2… straight section

Claims

1. A primary pulley including a first fixed sheave fixed to an input shaft and a first movable sheave movably attached to the input shaft in an axial direction; A secondary pulley including a second fixed sheave fixed to an output shaft and a second movable sheave movably attached to the output shaft in an axial direction; A power transmission component wound around the primary pulley and the secondary pulley for transmitting power from the primary pulley to the secondary pulley; A guide rail disposed in a straight section of the power transmission component away from the primary pulley and the secondary pulley; characterized by comprising: The guide rail includes a first rail end portion contacting the first fixed sheave and the first movable sheave, and a second rail end portion contacting the second fixed sheave and the second movable sheave. A continuously variable transmission.

2. The continuously variable transmission according to Claim 1, wherein the first rail end portion includes a first contact portion contacting the first fixed sheave and a second contact portion contacting the first movable sheave; the second rail end portion includes a third contact portion contacting the second fixed sheave and a fourth contact portion contacting the second movable sheave; the first contact portion and the second contact portion are movably attached to the first rail end portion in a width direction of the guide rail; the third contact portion and the fourth contact portion are movably attached to the second rail end portion in a width direction of the guide rail. A continuously variable transmission.

3. The continuously variable transmission according to Claim 1, characterized by comprising a housing for accommodating the primary pulley and the secondary pulley, and a rod attached to the housing for swingably supporting the guide rail. A continuously variable transmission.

4. The continuously variable transmission according to Claim 1, characterized by comprising a housing for accommodating the primary pulley and the secondary pulley, a first biasing unit including a first base end portion attached to the housing and a first tip end portion biasing the guide rail toward the power transmission component, and a second biasing unit including a second base end portion attached to the housing and a second tip end portion biasing the guide rail toward the power transmission component; wherein the first tip end portion contacts the guide rail on a side of the first rail end portion rather than a center of the guide rail. A continuously variable transmission. ​ The second tip portion is in contact with the second rail end side rather than the center of the guide rail. Continuously variable transmission.

5. In the continuously variable transmission according to claim 4, The first base end portion and the second base end portion are attached to the housing so as to be movable in the width direction of the guide rail. Continuously variable transmission.

Images