Toroidal type continuously variable transmission

Abstract

To provide a toroidal continuously variable transmission which can rigidly fix a lubricant distribution member to a support shaft for rotatably supporting a power roller, and can prevent the movement of the lubricant distribution member to the support shaft from a prescribed position at an operation.SOLUTION: A toroidal continuously variable transmission comprises a ring-shaped lubricant distribution member 100 arranged between a support shaft 23b for supporting a power roller 11 and a thrust bearing 24, and having a plurality of distribution paths 100a for distributing and sending the lubricant toward the thrust bearing 24, and both the support shaft 23b and the lubricant distribution member 100 are formed of metals. The toroidal continuously variable transmission also has a movement prevention structure for preventing the movement of the lubricant distribution member 100 to the support shaft 23b from a prescribed position. The movement prevention structure is, for example, a structure in which the lubricant distribution member 100 is shrink-fit and fixed to the support shaft 23b.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a toroidal type continuously variable transmission that can be used in generators for automobiles and aircraft, or transmissions for various industrial machines, etc. [Background technology]

[0002] For example, a double-cavity toroidal type continuously variable transmission used as an automobile transmission is configured as shown in Figures 9 and 10. As shown in Figure 9, an input shaft 1 is rotatably supported inside a casing 50, and two input side discs 2, 2 and two output side discs 3, 3 are attached to the outer periphery of this input shaft 1. An output gear (transmission gear) 4 is rotatably supported on the outer periphery of a middle part of the input shaft 1. The output side discs 3, 3 are connected to cylindrical flanges 4a, 4a provided in the center of this output gear 4 by spline coupling. The input shaft 1 is rotated by a drive shaft 22 via a loading cam type pressing device 12 provided between the input side disc 2 located on the left side in Fig. 9 and a cam plate (loading cam) 7. The output gear 4 is supported in a casing 50 via a partition wall 13 formed by joining two members, which allows the output gear 4 to rotate around the axis O of the input shaft 1 while preventing displacement in the direction of the axis O.

[0003] The output side discs 3, 3 are supported rotatably about the axis O of the input shaft 1 by needle bearings 5, 5 interposed between them and the input shaft 1. The input side disc 2 on the left side in FIG. 9 is supported on the input shaft 1 via a ball spline 6, and the input side disc 2 on the right side in FIG. 9 is spline-connected to the input shaft 1, so that these input side discs 2 rotate together with the input shaft 1. Power rollers 11 (see FIG. 10) are rotatably sandwiched between inner surfaces (concave surfaces; also called traction surfaces) 2a, 2a of the input side discs 2, 2 and inner surfaces (concave surfaces; also called traction surfaces) 3a, 3a of the output discs 3, 3.

[0004] A step portion 2b is provided on the inner peripheral surface 2c of the input side disc 2 located on the right side in Fig. 9, and a step portion 1b provided on the outer peripheral surface 1a of the input shaft 1 abuts against this step portion 2b, and the back surface of the input side disc 2 (the right surface in Fig. 9) abuts against a loading nut 9 screwed into a threaded portion formed on the outer peripheral surface of the input shaft 1. This substantially prevents the input side disc 2 from being displaced in the direction of the axis O relative to the input shaft 1. In addition, a disc spring 8 is provided between the cam plate 7 and the flange portion 1d of the input shaft 1, and this disc spring 8 applies a pressing force (preload) to the contact portions between the concave surfaces 2a, 2a, 3a, 3a of the discs 2, 2, 3, 3 and the peripheral surfaces 11a, 11a of the power rollers 11, 11.

[0005] FIG. 10 is a cross-sectional view taken along line AA in FIG. 9. As shown in FIG. 10, a pair of trunnions 15, 15 are provided inside the casing 50, which swing about a pair of pivots 14, 14 that are in a twisted position relative to the input shaft 1. Note that the input shaft 1 is not shown in FIG. 10. Each trunnion 15, 15 has a pair of bent wall portions 20, 20 formed at both ends in the longitudinal direction (the vertical direction in FIG. 10) of the support plate portion 16, in a state of bending toward the inner surface side of the support plate portion 16. The bent wall portions 20, 20 form a concave pocket portion P in each trunnion 15, 15 for accommodating the power roller 11. In addition, the pivots 14, 14 are provided concentrically with each other on the outer surfaces of the bent wall portions 20, 20.

[0006] A circular hole 21 is formed in the center of the support plate portion 16, and a base end portion 23a of a displacement shaft 23 is supported in this circular hole 21. The inclination angle of the displacement shaft 23 supported in the center of each of the trunnions 15 can be adjusted by swinging each of the trunnions 15 about each of the pivots 14. The power rollers 11 are rotatably supported around the tip portion 23b of the displacement shaft 23 protruding from the inner surface of each of the trunnions 15, and each of the power rollers 11 is sandwiched between each of the input side disks 2 and each of the output side disks 3. The base end portion 23a and the tip portion 23b of each of the displacement shafts 23 are eccentric to each other.

[0007] The pivots 14, 14 of the trunnions 15, 15 are supported by a pair of yokes 23A, 23B so as to be swingable and displaceable in the axial direction (vertical direction in FIG. 10), and the horizontal movement of the trunnions 15, 15 is restricted by the yokes 23A, 23B. The yokes 23A, 23B are formed into a rectangular shape by pressing or forging a metal such as steel. Four circular support holes 18 are provided at the four corners of the yokes 23A, 23B, and the pivots 14 provided at both ends of the trunnions 15 are supported swingably in the support holes 18 via radial needle bearings 30. The yokes 23A, 23B are provided at the center in the width direction (horizontal direction in FIG. 10) with circular locking holes 19, and the inner peripheral surface of the locking holes 19 is a cylindrical surface, into which the spherical posts 64, 68 are fitted. That is, the upper yoke 23A is supported so as to be freely swingable by a spherical post 64 which is supported on the casing 50 via a fixed member 52, and the lower yoke 23B is supported so as to be freely swingable by a spherical post 68 and the upper cylinder body 56 of the drive cylinder 31 which supports it.

[0008] The displacement shafts 23, 23 provided on each trunnion 15, 15 are provided at positions 180 degrees opposite to each other with respect to the input shaft 1. The direction in which the tip end 23b of each of these displacement shafts 23, 23 is eccentric with respect to the base end 23a is the same as the direction of rotation of both disks 2, 2, 3, 3 (upside down in FIG. 10). The eccentric direction is substantially perpendicular to the direction in which the input shaft 1 is disposed. Therefore, each of the power rollers 11, 11 is supported so as to be slightly displaceable in the longitudinal direction of the input shaft 1. As a result, even if each of the power rollers 11, 11 tends to be displaced in the axial direction of the input shaft 1 due to elastic deformation of each component based on the thrust load generated by the pressing device 12, this displacement is absorbed without applying excessive force to each component.

[0009] Between the outer surface of the power roller 11 and the inner surface of the support plate portion 16 of the trunnion 15, a thrust ball bearing (thrust bearing) 24, which is a thrust rolling bearing, and a thrust needle bearing 25 are provided in this order from the outer surface side of the power roller 11. Of these, the thrust ball bearing 24 supports the thrust load applied to each power roller 11 while allowing each power roller 11 to rotate. Each thrust ball bearing 24 is composed of a plurality of balls (hereinafter referred to as rolling elements) 26, 26, an annular cage 27 that holds each of the rolling elements 26, 26 so that they can roll freely, and an annular outer ring 28. The inner ring raceway of each thrust ball bearing 24 is formed on the outer surface (large end surface) of each power roller 11, and the outer ring raceway is formed on the inner surface of each outer ring 28.

[0010] In addition, the thrust needle bearing 25 is sandwiched between the inner surface of the support plate portion 16 of the trunnion 15 and the outer surface of the outer ring 28. Such thrust needle bearing 25 supports the thrust load applied from the power rollers 11 to each outer ring 28, while allowing the power rollers 11 and the outer ring 28 to swing around the base end portion 23a of each displacement shaft 23.

[0011] Furthermore, one end of each trunnion 15 (the lower end in FIG. 10) is provided with a drive rod (trunnion shaft) 29, and a drive piston (hydraulic piston) 33 is fixed to the outer circumferential surface of the middle part of each drive rod 29. Each of these drive pistons 33 is oil-tightly fitted into a drive cylinder 31 formed by an upper cylinder body 56 and a lower cylinder body 57. Each of these drive pistons 33 and the drive cylinder 31 constitutes a drive unit 32 that displaces each of the trunnions 15 in the axial direction of the pivots 14 of the trunnions 15.

[0012] In the case of a toroidal type continuously variable transmission configured in this manner, the rotation of the input shaft 1 is transmitted to the input side discs 2, 2 via a pressing device 12. The rotation of these input side discs 2, 2 is then transmitted to the output side discs 3, 3 via a pair of power rollers 11, 11, and the rotation of each of the output side discs 3, 3 is further taken out by the output gear 4.

[0013] When changing the rotational speed ratio between the input shaft 1 and the output gear 4, the pair of drive pistons 33, 33 are displaced in opposite directions. With the displacement of each of the drive pistons 33, 33, the pair of trunnions 15, 15 are displaced in opposite directions. For example, the power roller 11 on the left side of Fig. 10 is displaced downward in the same figure, and the power roller 11 on the right side of the same figure is displaced upward in the same figure. As a result, the direction of the tangential force acting on the contact portions between the peripheral surfaces 11a, 11a of the power rollers 11, 11 and the inner surfaces 2a, 2a, 3a, 3a of the input side disks 2, 2 and the output side disks 3, 3 changes. Then, with the change in the direction of the force, the trunnions 15, 15 swing (tilt) in opposite directions to each other about the pivots 14, 14 pivoted to the yokes 23A, 23B.

[0014] As a result, the contact position between the circumferential surface 11a, 11a of each power roller 11, 11 and each inner surface 2a, 3a changes, and the rotation speed ratio between the input shaft 1 and the output gear 4 changes. In addition, when the torque transmitted between the input shaft 1 and the output gear 4 fluctuates and the elastic deformation amount of each component changes, each power roller 11, 11 and the outer rings 28, 28 attached to each power roller 11, 11 rotate slightly around the base end portion 23a, 23a of each displacement shaft 23, 23. Since the thrust needle bearings 25, 25 are present between the outer surface of each outer ring 28, 28 and the inner surface of the support plate portion 16 constituting each trunnion 15, 15, the rotation is performed smoothly. Therefore, as described above, a small force is required to change the inclination angle of each displacement shaft 23, 23.

[0015] Incidentally, in the toroidal type continuously variable transmission configured as described above, since a large thrust load is applied to the thrust ball bearing 24 supporting the power roller 11, a structure is provided for supplying lubricating oil to the periphery of the rolling elements 26, 26 of this thrust ball bearing 24. Conventionally, lubricating oil is supplied to this thrust ball bearing (thrust bearing) 24 by forming an oil hole in the shaft (support shaft) 23b that passes through the center of the thrust ball bearing 24, and discharging lubricating oil from the inside of the thrust ball bearing 24 through this oil hole. However, in order to discharge the lubricating oil from the oil hole of the shaft and distribute it to the thrust bearing in an appropriate ratio, it is necessary to form the opening of the oil hole at an appropriate position with high precision, which increases the processing cost of the shaft. Therefore, if the opening of the oil hole is not formed with high precision, it is difficult to supply the lubricating oil from the oil hole to the thrust bearing in an appropriate amount, direction, position and ratio. For example, as described in Patent Document 1, a ring-shaped lubricating oil distribution member is provided between the shaft (support shaft) and the thrust bearing, and this lubricating oil distribution member is provided with multiple distribution paths that distribute and send the lubricating oil supplied from the oil hole to the thrust rolling bearing, so that the lubricating oil is distributed in an appropriate amount and ratio to the inner ring (power roller) side and the outer ring side of the thrust bearing. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] JP 2012-225479 A Summary of the Invention [Problem to be solved by the invention]

[0017] However, in the conventional toroidal type continuously variable transmission described in Patent Document 1, the lubricant distribution member is made of resin (e.g., fluororesin), while the support shaft is made of metal such as hardened steel, and the lubricant distribution member is fixed by simply pressing the lubricant distribution member into the support shaft, so the tightening force of the lubricant distribution member made of resin is low, and because the lubricant distribution member is made of resin, deformation occurs due to high temperatures and vibration during operation. In addition, while the lubricant distribution member is made of resin, the support shaft is made of metal, so the difference in thermal expansion coefficient (or linear thermal expansion coefficient) between the lubricant distribution member and the support shaft becomes large. Therefore, when the temperature becomes high during operation, the lubricant distribution member expands more than the support shaft. As a result, a gap is generated between the support shaft and the lubricant distribution member, and there is a risk that the lubricant distribution member will move in the axial direction of the support shaft. If the lubricant distribution member moves toward the power roller in the axial direction of the support shaft, contact with the rotating power roller will occur, which may lead to a decrease in power transmission efficiency, progression of wear at the contact portion, and peeling of the power roller bearing due to the generation of wear powder.

[0018] The present invention has been made in consideration of the above circumstances, and aims to provide a toroidal type continuously variable transmission in which a lubricant distribution member can be firmly fixed to a support shaft that rotatably supports a power roller, and in which the lubricant distribution member can be prevented from moving from a predetermined position relative to the support shaft during operation. [Means for solving the problem]

[0019] In order to achieve the above object, the toroidal type continuously variable transmission of the present invention comprises a first disk and a second disk, which are concentrically and rotatably arranged with their inner surfaces facing each other; a power roller sandwiched between the first disc and the second disc; a trunnion that tilts about a pivot axis that is in a twisted position with respect to a central axis of the first disk and the second disk and supports the power roller rotatably about a support shaft; a thrust bearing that rotatably supports the power roller while receiving a thrust load applied to the power roller; an oil hole that opens to an outer peripheral surface of the support shaft and supplies lubricating oil toward the thrust bearing; a ring-shaped lubricant oil distribution member that is passed through the support shaft and disposed between the support shaft and the thrust bearing, and that has a plurality of distribution paths that distribute and send lubricant oil supplied from the oil hole toward the thrust bearing, Both the support shaft and the lubricant distribution member are made of metal; The lubricant distribution member may further include a movement prevention structure for preventing the lubricant distribution member from moving from a predetermined position on the support shaft. Here, the "predetermined position" refers to the location where the lubricant distribution member is fixed to the support shaft as designed.

[0020] In the present invention, both the support shaft and the lubricant distribution member are made of metal and have a movement prevention structure that prevents the lubricant distribution member from moving from its designated position on the support shaft, so that the lubricant distribution member can be firmly fixed to the support shaft and the lubricant distribution member can be prevented from moving from its designated position on the support shaft during operation at high temperatures, high rotation speeds, and high vibrations.

[0021] In the above-described configuration of the present invention, the movement prevention structure may be a structure in which the lubricant distribution member is fixed to the support shaft by shrink fitting, or a structure in which the support shaft is fixed to the lubricant distribution member by cold fitting.

[0022] Here, the shrink-fitted structure refers to a structure in which the inner diameter dimension of the lubricant distribution member before shrink-fitting (at room temperature) is made smaller than the outer diameter finish dimension of the support shaft, and the lubricant distribution member is heated to expand so that the inner diameter dimension becomes larger than the finish dimension of the support shaft, and then the lubricant distribution member is fitted onto the support shaft and then cooled to fix the lubricant distribution member to the support shaft. In addition, the term "cold-fit fixed structure" refers to a structure in which the outer diameter finishing dimension of the support shaft before cold fitting (at room temperature) is made larger than the inner diameter dimension of the lubricant distribution member, the support shaft is cooled and contracted so that the outer diameter dimension of the support shaft becomes smaller than the inner diameter dimension of the lubricant distribution member, the support shaft is fitted into the lubricant distribution member, and then returned to room temperature, thereby fixing the lubricant distribution member to the support shaft.

[0023] In the above-mentioned configuration of the present invention, the support shaft may have a tapered structure in which the diameter becomes larger toward the tip side of the support shaft.

[0024] Here, the tapered structure can be achieved, for example, by making the outer diameter dimension of the upper side (the needle bearing side for supporting the inner ring bearing (power roller side)) of the support shaft slightly (a few μm) larger than the outer diameter dimension of the lower side (base end side) of the support shaft, and making the tightening force of the upper side of the lubricant distribution member greater than that of the lower side, thereby preventing movement of the lubricant distribution member (preventing movement of the support shaft in the axial direction).

[0025] In the above-described configuration of the present invention, a stepped portion may be formed on an outer periphery of the support shaft, the stepped portion being in contact with an end face of the lubricant oil distribution member on the power roller side.

[0026] Here, when forming a stepped portion on the outer periphery of the support shaft, a circumferential groove may be formed to reduce the diameter of the outer diameter portion of the support shaft by the width into which the lubricant distribution member fits, or an annular flange portion may be formed to widen the diameter of the upper side of the support shaft (the needle bearing side for supporting the inner ring bearing (power roller side)). In addition, the lubricant distribution member is fixed to the support shaft by shrink fitting, and the inner diameter of the lubricant distribution member that expands when heated becomes larger than the diameter of the stepped portion, and the interference is maintained even on the smaller diameter side of the stepped portion of the support shaft. During operation, the lubricant distribution member becomes hot and expands in inner diameter, but the support shaft also expands, so the inner diameter does not become larger than the diameter of the stepped portion. Therefore, the lubricant distribution member can be prevented from moving from its designated position on the support shaft.

[0027] In the above-described configuration of the present invention, the movement prevention structure may be a structure in which the lubricant oil distribution member is fixed to the support shaft by crimping.

[0028] Here, it is preferable to provide a crimped portion (step) on the upper side (the inner ring bearing support needle bearing side (power roller side)) of the lubricant distribution member. This is because the lubricant distribution member is a thin ring-shaped member and may be deformed if it is crimped at the outer diameter part. In addition, when a stepped portion is formed on the support shaft, the inner diameter of the lubricant distribution member can be made slightly larger than the outer diameter of the stepped portion so that the lubricant distribution member can be fitted to the support shaft even at room temperature. Also, the inner diameter of the lubricant distribution member can be made smaller than the outer diameter of the support shaft so that the lubricant distribution member can be fixed to the support shaft by shrink fitting. Thereafter, the crimping portion provided on the upper side of the lubricant distribution member is crimped and fixed. When a stepped portion is formed on the support shaft, the crimped portion engages with the stepped portion, preventing the lubricant distribution member from moving from a predetermined position on the support shaft.

[0029] In the above-described configuration of the present invention, the movement prevention structure may be a structure in which a stepped groove is formed in the support shaft along a circumferential direction, and the lubricant oil distribution member is fixed to the stepped groove by crimping.

[0030] Here, it is preferable to set the groove width of the stepped groove to be approximately equal to the width of the lubricant distribution member (the width in the axial direction of the lubricant distribution member). In this way, the lubricant distribution member is engaged with the stepped groove and fixed by crimping.

[0031] In addition, in the above-mentioned configuration of the present invention, in the crimped structure, the lubricant distribution member may be fixed to the support shaft by shrink fitting, or the support shaft may be fixed to the lubricant distribution member by cold fitting.

[0032] In addition, in the above-described configuration of the present invention, the movement prevention structure may be a structure in which a protruding member fitted into a recess formed on the outer periphery of the support shaft so as to protrude from the outer periphery abuts against the end face of the lubricant distribution member on the power roller side.

[0033] Here, the recesses may be holes or grooves formed at predetermined intervals in the circumferential direction on the outer periphery of the support shaft, or may be a circumferential groove formed continuously along the circumferential direction.

[0034] In the above-described configuration of the present invention, the recess may be a circumferential groove formed continuously along an outer periphery of the support shaft, and the protruding member may be a retaining ring fitted into the circumferential groove.

[0035] In the above-mentioned configuration of the present invention, the lubricant distribution member may be fixed to the support shaft by shrink fitting, or the support shaft may be fixed to the lubricant distribution member by cold fitting.

[0036] In the above-described configuration of the present invention, the lubricant distribution member may be formed of a metal having a thermal expansion coefficient equal to or close to that of the support shaft. Here, the thermal expansion coefficients that are close to each other are those that have a difference of 25 (10 -6 / K(m)). In this case, it is preferable that the metal forming the support shaft has a greater thermal expansion coefficient than the metal forming the lubricant distribution member.

[0037] According to this configuration, since the lubricant distribution member is made of a metal with a thermal expansion coefficient equal to or close to that of the support shaft, even if the inner diameter of the lubricant distribution member expands due to high temperatures during operation, the support shaft also expands in the same manner, so the fitting state (fixed state) of the two is maintained. Therefore, it is possible to more reliably prevent the lubricant distribution member from moving from its designated position on the support shaft. Effect of the Invention

[0038] According to the present invention, the lubricant distribution member can be firmly fixed to the support shaft that rotatably supports the power roller, and the lubricant distribution member can be prevented from moving from a predetermined position relative to the support shaft during operation. [Brief description of the drawings]

[0039] [Figure 1] FIG. 1 is a cross-sectional view showing a trunnion equipped with a power roller, according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing a power roller unit including a power roller according to the first embodiment. [Diagram 3] 1A is a front view of the lubricant distribution member, and FIG. 1B is a plan view of the lubricant distribution member. [Figure 4] FIG. 4 is a cross-sectional view showing the support shaft of the power roller according to the first embodiment. [Diagram 5] FIG. 10 is a cross-sectional view showing a support shaft of a power roller according to a second embodiment of the present invention. [Figure 6] FIG. 10 is a cross-sectional view showing a support shaft of a power roller according to a third embodiment of the present invention. [Figure 7] FIG. 10 is a cross-sectional view showing a support shaft of a power roller according to a fourth embodiment of the present invention. [Figure 8] FIG. 10 is a cross-sectional view showing a support shaft of a power roller according to a fifth embodiment of the present invention. [Figure 9] FIG. 1 is a cross-sectional view showing an example of a conventional toroidal type continuously variable transmission. [Figure 10] FIG. 10 is a cross-sectional view taken along the line AA in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0040] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The present invention is characterized by the material and movement prevention structure of the lubricant distribution member that distributes the appropriate amount of lubricant at an appropriate ratio to the thrust bearing 24 of the power roller 11, and the other configurations and functions are the same as those of the conventional configurations and functions described above. Therefore, in the following, the characteristic parts of the present invention will be described, and the same reference numerals will be used to designate the same configurations as the conventional configurations, and the description thereof may be omitted.

[0041] (First embodiment) Figures 1 to 3 show a first embodiment, where Figure 1 is a cross-sectional view showing a trunnion 15 equipped with a power roller 11, Figure 2 is a cross-sectional view showing a power roller unit PU equipped with a power roller 11, Figure 3 is a diagram showing a lubricant distribution member, and Figure 4 is a cross-sectional view of a displacement shaft 23 including an outer ring 11b. 1, the trunnion 15 has a vertically long support plate portion 16 and a pair of bent wall portions 20, 20 formed at both ends (upper and lower ends) of the support plate portion 16 in a state of being bent toward the inner surface side of the support plate portion 16. The bent wall portions 20, 20 form a concave pocket portion P in the trunnion 15 for accommodating the power roller 11. In addition, pivots 14, 14 are provided concentrically with each other on the outer surfaces of the bent wall portions 20, 20.

[0042] 1 and 2, the power roller 11 is configured by an inner ring 11c of a thrust bearing 24. Between the outer surface of the inner ring 11c and the inner surface of the support plate portion 16 of the trunnion 15, a thrust ball bearing (thrust bearing) 24, which is a thrust rolling bearing, and a thrust needle bearing 25 are provided in this order from the outer surface side of the inner ring 11c. Of these, the thrust ball bearing 24 supports the thrust load applied to the power roller 11 (inner ring 11c) while allowing the power roller 11 (inner ring 11c) to rotate. Such a thrust ball bearing 24 is composed of a plurality of balls (hereinafter referred to as rolling elements) 26, an annular cage 27 that holds the rolling elements 26 so that they can roll freely, the inner ring 11c which is the power roller 11, and an annular outer ring 11b. The inner ring raceway of the thrust ball bearing 24 is formed on the outer surface (large end surface) of the inner ring 11c, and the outer ring raceway is formed on the inner surface of the outer ring 11b.

[0043] Further, a circular hole is formed in the center of the support plate portion 16, and a base end portion 23a of a displacement shaft 23 is inserted into this circular hole so as to be rotatable about its axis. The tip portion of this displacement shaft 23 is a support shaft 23b, and the power roller 11 is rotatably supported by this support shaft 23b. That is, a hole 11d is formed in the power roller 11, a radial needle bearing 23g is inserted into this hole 11d, and the support shaft 23b is rotatably supported by this radial needle bearing 23g.

[0044] The thrust needle bearing 25 is sandwiched between the inner surface of the support plate portion 16 of the trunnion 15 and the outer surface of the outer ring 11b, and comprises a flat race 25a arranged along the inner surface of the support plate portion 16 of the trunnion 15, a disk-shaped retainer 25b in which pocket holes are formed at predetermined intervals in the circumferential direction, and a plurality of needles 25c housed in the pocket holes.

[0045] Further, an oil passage 74 is provided in the support shaft 23b. This oil passage 74 is provided inside the support shaft 23b and extends along its axial direction, and the base ends of a plurality of oil passages 75 that extend in a direction perpendicular to the axial direction of the support shaft 23b and are provided at predetermined intervals in the circumferential direction are connected to this oil passage 74. The tip ends of the oil passages 75 are oil holes 75a that open into the outer peripheral surface of the support shaft 23b, and lubricating oil is discharged and sent from this oil hole 75a toward the thrust bearing 24. Furthermore, oil passage 74 of support shaft 23b is connected to oil passage 76 of trunnion 15 via oil passages 77 and 78, and oil passage 76 is connected to oil passage 79. Furthermore, oil passage 80 is connected to oil passage 79. Lubricating oil is supplied to oil passage 80 from oil hole 80a, and is supplied to oil passage 74 via oil passages 79, 76, 77, and 78. The configuration for supplying lubricating oil to the oil passage 74 of the support shaft 23b is not limited to the above configuration, and various configurations are applicable.

[0046] Between the support shaft 23b and the cage 27 of the thrust bearing 24, a ring-shaped lubricant distribution member 100 is provided, passing through the support shaft 23b. This lubricant distribution member 100 distributes and sends the lubricant supplied from the oil hole 75a to the thrust bearing 24, and has a plurality of distribution paths 100a. These distribution paths 100a are inclined with respect to the axis of the lubricant distribution member 100. A recess 100f is formed along the circumferential direction on the inner diameter side of the lubricant distribution member 100, and the base end of the distribution path 100a opens to the bottom surface of this recess 100f.

[0047] 3, the lubricant distribution member 100 is formed in a circular ring shape, and the outer circumferential surface is composed of two truncated cone-shaped inclined surfaces 100b, 100c inclined with respect to the axial direction of the lubricant distribution member 100, and a cylindrical parallel surface 100d connecting the inclined surfaces 100b, 100c and parallel to the axial direction of the lubricant distribution member 100. The inclined surface 100b is formed on the upper surface side of the lubricant distribution member 100, and the inclined surface 100c is formed on the lower surface side of the lubricant distribution member 100. The ends of the multiple distribution paths 100a open onto the inclined surfaces 100b, 100c, and lubricating oil is discharged from the distribution path 100a opening onto the inclined surface 100b to the inner ring 11c (power roller 11) side of the thrust bearing 24, and lubricating oil is discharged from the distribution path 100a opening onto the inclined surface 100c to the outer ring 11b side. In addition, the lubricant distribution member 100 is formed from metals such as "steel (steel, stainless steel, etc.) and non-ferrous metals (aluminum, copper, titanium, etc.)", and such metal lubricant distribution member 100 is prevented from moving from a predetermined position on the support shaft 23b by an anti-movement structure. Here, the "predetermined position" refers to the portion where the lubricant distribution member 100 is fixed to the support shaft 23b as designed, for example, the portion of the large diameter shaft portion 23d of the support shaft 23b, which will be described later, as shown in FIG. The lubricant distribution member 100 is made of a metal having a thermal expansion coefficient (or linear thermal expansion coefficient) equal to or close to that of the support shaft 23b. For example, when the lubricant distribution member 100 is made of carbon steel, it is preferable that the support shaft 23b is also made of carbon steel. The lubricant distribution member 100 and the support shaft 23b may be made of different metals, but the thermal expansion coefficients are equal to or close to each other (for example, the difference in the thermal expansion coefficients is 25 (10 -6 In this case, it is preferable that the metal forming the support shaft 23b has a larger thermal expansion coefficient than the metal forming the lubricant distribution member 100. In the second to fifth embodiments described later, the lubricant distribution member 100 is also made of a metal having a thermal expansion coefficient (or linear thermal expansion coefficient) equal to or close to that of the support shaft 23b. In addition, the support shaft 23b constitutes the tip portion of the displacement shaft 23, but since the support shaft 23b is formed integrally with the outer ring 11b and the base end portion 23a of the displacement shaft 23, the outer ring 11b and the base end portion 23a are also formed from the same metal as the support portion 23b.

[0048] As shown in Fig. 4, the movement prevention structure of the first embodiment is a structure in which the lubricant distribution member 100 is shrink-fitted to the support shaft 23b (shrink-fitted structure), or a structure in which the support shaft 23b is cold-fitted to the lubricant distribution member 100 (cold-fitted structure). The support shaft 23b is composed of a large-diameter shaft portion 23d integrally formed with the outer ring 11b, and a small-diameter shaft portion 23e having a smaller diameter than the large-diameter shaft portion 23d and integrally formed coaxially with the large-diameter shaft portion 23d, and the power roller 11 (inner ring 11c) is rotatably supported by the small-diameter shaft portion 23e via a radial needle bearing 23g (see Fig. 2).

[0049] The lubricant distribution member 100 is shrink-fitted to the large diameter shaft portion 23d of the support shaft 23b. In this shrink-fitted structure, the inner diameter of the lubricant distribution member 100 before shrink-fitting (at room temperature) is set to a value smaller than the outer diameter finish dimension of the large diameter shaft portion 23d of the support shaft 23b, and the lubricant distribution member 100 is heated to expand so that the inner diameter dimension becomes larger than the finish dimension of the large diameter shaft portion 23d, and then the lubricant distribution member 100 is fitted into the large diameter shaft portion 23d, and then cooled to fix the lubricant distribution member 100 to the large diameter shaft portion 23d. Moreover, the height dimension h1 from the upper surface (upper surface on which the support shaft 23b is provided) 11e of the outer ring 11b of the large diameter shaft portion 23d is longer than the axial height dimension h2 of the lubricant distribution member 100, and the lower end surface of the lubricant distribution member 100 abuts against the upper surface 11e. Therefore, the upper end surface of the lubricant distribution member 100 is lower than the upper surface of the large diameter shaft portion 23d, so that the entire inner diameter surface of the lubricant distribution member 100 is shrink-fitted and fixed to the outer diameter surface of the large diameter shaft portion 23d.

[0050] In addition, in the structure fixed by cold fitting, the outer diameter finishing dimension of the large diameter shaft portion 23d of the support shaft 23b before cold fitting (at room temperature) is set to a value larger than the inner diameter dimension of the lubricant distribution member 100, and the large diameter shaft portion 23d is cooled to shrink the outer diameter dimension of the large diameter shaft portion 23d to be smaller than the inner diameter dimension of the lubricant distribution member 100.The large diameter shaft portion 23d is then fitted into the lubricant distribution member 100, and then returned to room temperature, thereby fixing the lubricant distribution member 100 to the large diameter shaft portion 23d. When cooling the large diameter shaft portion 23d, the entire displacement shaft 23 including the outer ring 11b may be cooled, the support shaft 23b including the large diameter shaft portion 23d may be cooled, or only the large diameter shaft portion 23d may be cooled.

[0051] According to the first embodiment, both the support shaft 23b and the lubricant distribution member 100 are made of metal and have a movement prevention structure (shrink-fit fixing structure or cold-fit fixing structure) that prevents the lubricant distribution member 100 from moving from the large diameter shaft portion 23d of the support shaft 23b. Therefore, the lubricant distribution member 100 can be firmly fixed to the support shaft 23b, and the lubricant distribution member 100 will not move from its designated position (large diameter shaft portion 23d) on the support shaft 23 during operation at high temperatures, high rotation speeds, and high vibrations. In addition, since the lubricant distribution member 100 is made of a metal with a thermal expansion coefficient equal to or close to that of the support shaft 23b, even if the inner diameter of the lubricant distribution member 100 expands due to high temperatures during operation, the support shaft 23b also expands in the same manner, so that the fitting state (fixed state) of the two is maintained. This makes it possible to more reliably prevent the lubricant distribution member 200 from moving from the specified position on the support shaft 23b.

[0052] Second embodiment The movement prevention structure of the second embodiment has a tapered structure in which the large diameter shaft portion 23d of the support shaft 23b has a larger diameter toward the tip side of the support shaft 23b, as shown in Fig. 5. In the second to fifth embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. As the tapered structure, for example, the outer diameter dimension d1 of the upper side (small diameter shaft portion 23e side) of the large diameter shaft portion 23d of the support shaft 23b is made slightly (several μm) larger than the outer diameter dimension d2 of the lower side (base end side) of the large diameter shaft portion 23d support shaft, and the outer peripheral surface of the large diameter shaft portion 23d is formed into a tapered surface intersecting the axial direction. In this way, by making the outer peripheral surface of the large diameter shaft portion 23d a tapered surface, the tightening force of the upper side of the lubricant distribution member 100 is made larger than that of the lower side, thereby forming a movement prevention structure that prevents the lubricant distribution member 100 from moving. The movement prevention structure of the second embodiment also has a shrink-fit fixing structure or a cold-fit fixing structure, similar to the first embodiment.

[0053] According to the second embodiment, in addition to the shrink-fit fixing structure or the cold-fit fixing structure, the clamping force on the upper side of the lubricant distribution member 100 is greater than that on the lower side, so that the fixing strength of the lubricant distribution member 100 can be increased more than that of the first embodiment.

[0054] (Third embodiment) In the movement prevention structure of the third embodiment, as shown in FIG. 6, a stepped portion 110 that abuts on the end face of the lubricant oil distribution member 100 on the power roller side is formed on the outer periphery of the large diameter shaft portion 23d of the support shaft 23b. When forming the stepped portion 110 on the outer periphery of the large diameter shaft portion 23d, a circumferential groove 111 may be formed so as to reduce the diameter of the outer diameter portion of the large diameter shaft portion 23d by the width where the lubricant distribution member fits, or an annular flange portion 112 may be formed so as to widen the diameter of the upper side (small diameter shaft portion 23e side) of the large diameter shaft portion 23d. When forming the circumferential groove 111, the outer diameter of the portion where the circumferential groove 111 is formed is smaller than the outer diameter of the large diameter shaft portion 23d of the first embodiment shown in FIG. 4, so the inner diameter of the lubricant distribution member 100 is reduced accordingly. Also, when forming the flange portion 112, the inner diameter of the lubricant distribution member 100 is slightly increased.

[0055] As in the first embodiment, the lubricant distribution member 100 is shrink-fitted and fixed to the large diameter shaft portion 23d of the support shaft 23b, but the inner diameter dimension of the lubricant distribution member 100 that has been heated and expanded becomes larger than the diameter of the stepped portion 110, and the tightening margin is maintained even on the smaller diameter side of the stepped portion 110 of the large diameter shaft portion 23d. During operation, the lubricant distribution member 100 becomes hot and its inner diameter expands, but the large diameter shaft portion 23d of the support shaft 23b also expands, so the fitted state (fixed state) of the two is maintained, and the inner diameter of the lubricant distribution member 100 does not become larger than the diameter of the stepped portion 110. Therefore, the lubricant distribution member 100 can be prevented from moving from the specified position (large diameter shaft portion 23d) of the support shaft 23b. That is, when the lubricant distribution member 100 is shrink-fitted, the inner diameter of the lubricant distribution member 100 is larger than the outer diameter of the stepped portion 110, and when cooled, the inner diameter of the lubricant distribution member 100 is smaller than the outer diameter of the stepped portion 110, so that the lubricant distribution member 100 can be prevented from moving from the predetermined position (large diameter shaft portion 23d) of the support shaft 23b, and further, although the inner diameter of the lubricant distribution member 100 expands during operation, the large diameter shaft portion 23d of the support shaft 23b also expands, so that the inner diameter of the lubricant distribution member 100 does not become larger than the diameter of the stepped portion 110. Therefore, the lubricant distribution member 100 can be prevented from moving from the large diameter shaft portion 23d of the support shaft 23b.

[0056] (Fourth embodiment) As shown in FIG. 7, the movement prevention structure of the fourth embodiment has a structure in which a lubricant distribution member 100 is fixed to a large diameter shaft portion 23d of a support shaft 23b by crimping. In this embodiment, a crimped portion (step) 100k is provided on the upper side (small diameter shaft portion 23e side) of the lubricant distribution member 100. This crimped portion 100k is formed by cutting out the upper part of the lubricant distribution member 100 in an L-shaped cross section to form a step, so that the outer diameter dimension of the crimped portion 100k is smaller than the outer diameter dimension below the crimped portion 100k (outer ring 11b side). Therefore, the crimped portion 100k has a small radial thickness and is easy to crimp. On the other hand, if the lubricant distribution member 100 is crimped at the outer diameter portion without providing the crimped portion 100k, the lubricant distribution member 100 is a thin ring-shaped member, so there is a risk of deformation, and the distribution passage 100a may be deformed or crushed due to this deformation, but by providing the crimped portion 110k, such a risk does not occur.

[0057] In addition, when a stepped portion 110 is formed on the large diameter shaft portion 23d of the support shaft 23b, the inner diameter dimension of the lubricant distribution member 100 is made slightly larger than the outer diameter dimension of the stepped portion 110, so that the lubricant distribution member 100 can be fitted into the large diameter shaft portion 23d even at room temperature. Alternatively, a stepped portion 110 may be formed on the large diameter shaft portion 23d, so that a stepped groove 115 is formed between the lower surface of the stepped portion 110 and the upper surface of the outer ring 11b along the circumferential direction, and the lubricant distribution member 100 may be crimped and fixed to the stepped groove 115. In this case, by making the vertical width dimension of the stepped groove 115 (the axial width dimension of the support shaft 23b) and the axial width dimension of the lubricant distribution member 100 approximately equal, the lubricant distribution member 100 can be fitted into the stepped groove 115 even at room temperature. Thereafter, the lubricant distribution member 100 is crimped, so that the lubricant distribution member 100 engages with the stepped groove 115 and is firmly crimped and fixed.

[0058] In addition, the inner diameter dimension of the lubricant distribution member 100 can be made smaller than the outer diameter of the large diameter shaft portion 23d, and the lubricant distribution member 100 can be fixed to the large diameter shaft portion 23d by shrink fitting, or the outer diameter finishing dimension of the large diameter shaft portion 23d of the support shaft 23b can be made larger than the inner diameter dimension of the lubricant distribution member 100, and the lubricant distribution member 100 can be fixed to the large diameter shaft portion 23d by shrink fitting. Thereafter, the crimping portion 100k provided on the upper portion of the ring of the lubricant distribution member 100 is crimped to fix it to the large diameter shaft portion 23d. When the stepped portion 110 is formed on the large diameter shaft portion 23d, the crimped portion 100d engages with the stepped portion 110, thereby preventing the lubricant distribution member 100 from coming off the large diameter shaft portion 23d.

[0059] In this embodiment, the stepped portion 110 is formed on the large diameter shaft portion 23d of the support shaft 23b, but the lubricant oil distribution member 100 may be fixed to the large diameter shaft portion 23d by crimping without forming the stepped portion 110.

[0060] Fifth embodiment In the movement prevention structure of the fifth embodiment, as shown in Figure 8, a protruding member 117 is fitted into a recess 116 formed on the outer periphery of the large diameter shaft portion 23d of the support shaft 23b so as to protrude from the outer periphery, and abuts against the end face of the lubricant distribution member 100 on the power roller side.

[0061] Here, the recess 116 may be a hole or groove formed at a predetermined interval in the circumferential direction on the outer periphery of the large diameter shaft portion 23d, or may be a circumferential groove formed continuously along the circumferential direction; however, in this embodiment, the recess 116 is a circumferential groove 116 formed continuously along the outer periphery of the large diameter shaft portion 23d, and the protruding member 117 is a retaining ring 117 fitted into the circumferential groove 116. The circumferential groove 116 is formed to have a U-shaped cross section, and the vertical dimension between the lower wall surface 116a of this circumferential groove 116 and the upper surface of the outer ring 11b is approximately equal to the axial width dimension of the lubricant distribution member 100. Therefore, when the lubricant distribution member 100 is fitted onto the large diameter shaft portion 23d and the lower end surface of the lubricant distribution member 100 abuts against the upper surface of the outer ring 11b, the upper end surface of the lubricant distribution member 100 and the lower wall surface 116a of the circumferential groove 116 become approximately flush with each other.

[0062] The retaining ring 117 is made of a metal such as steel or stainless steel and is formed into a circular ring shape, and its inner diameter side is fitted into the circumferential groove 116. The outer diameter side of the retaining ring 117 protrudes radially from the outer circumferential surface of the large diameter shaft portion 23d, and this protruding portion abuts against the upper end surface of the lubricant distribution member 100, thereby preventing the large diameter shaft portion 23d of the support shaft 23b of the lubricant distribution member 100 from moving in the axial direction.

[0063] In addition, in this embodiment, before installing the retaining ring 117, the lubricant distribution member 100 may be fixed to the large diameter shaft portion 23d of the support shaft 23b by shrink fitting or cold fitting as described above, or may be further fitted by clearance fitting. In this embodiment, the ring-shaped retaining ring 117 serving as the protruding member is fitted into the circumferential groove 116 serving as the recess, but recesses may be formed at predetermined intervals in the circumferential direction of the large diameter shaft portion 23d, and a rod-shaped or plate-shaped protruding member may be fitted into each recess. In this case, in order to prevent the protruding member from slipping out of the recess, the protruding member is firmly fitted and fixed into the recess by press-fitting the protruding member into the recess or by using a combination of press-fitting and an adhesive. Furthermore, a through hole may be formed in the large diameter shaft portion 23d instead of a recess, and a spring pin may be driven into the through hole to prevent the shaft portion 23b of the lubricant oil distribution member 100 from moving in the axial direction.

[0064] In this embodiment, the present invention has been described by taking as an example a case where the present invention is applied to a double-cavity half-toroidal continuously variable transmission. However, the present invention is not limited to this, and can also be applied to a double-cavity full-toroidal continuously variable transmission, and further, can also be applied to a single-cavity half-toroidal continuously variable transmission, or a single-cavity full-toroidal continuously variable transmission.

[0065] In addition, in this embodiment, the shaft is the input shaft 1, the first disc is the input side disc 2, and the second disc is the output side disc 3. However, in a toroidal type continuously variable transmission, the input / output relationship between the input side disc and the output side disc may be reversed. Therefore, the present invention can also be applied to a case where the shaft is the output shaft, the first disc is the output side disc 3, and the second disc is the input side disc 2. [Explanation of symbols]

[0066] 1 Input shaft (shaft) 2 Input disk (first disk) 3 Output disk (second disk) 11(11c) Power roller (inner ring) 15 Trunnion 23b Support shaft 24 Thrust bearing 75a oil hole 100 Lubricant distribution member 100a distribution path 116 Circumferential groove (recess) 117 Protruding member (retaining ring)

Claims

1. a first disk and a second disk arranged concentrically and rotatably with their respective inner surfaces facing each other; a power roller sandwiched between the first disc and the second disc; a trunnion that tilts about a pivot axis that is in a twisted position with respect to central axes of the first disk and the second disk and supports the power roller rotatably about a support shaft; a thrust bearing that rotatably supports the power roller while receiving a thrust load applied to the power roller; an oil hole that opens to an outer peripheral surface of the support shaft and supplies lubricating oil toward the thrust bearing; a ring-shaped lubricant oil distribution member that is passed through the support shaft and disposed between the support shaft and the thrust bearing, and that has a plurality of distribution paths that distribute and send lubricant oil supplied from the oil hole toward the thrust bearing, Both the support shaft and the lubricant distribution member are made of metal; The lubricant distribution member is provided with a movement prevention structure for preventing the lubricant distribution member from moving from a predetermined position on the support shaft, The movement prevention structure is a structure in which the lubricant distribution member is fixed to the support shaft by shrink fitting, or a structure in which the support shaft is fixed to the lubricant distribution member by cold fitting, 1. A toroidal type continuously variable transmission, wherein the support shaft has a tapered structure in which the diameter of the support shaft increases toward the tip end thereof.

2. 2. The toroidal type continuously variable transmission according to claim 1, wherein a stepped portion is formed on an outer periphery of the support shaft, the stepped portion being brought into contact with an end face of the lubricant oil distribution member on the power roller side.

3. 2. The toroidal type continuously variable transmission according to claim 1, wherein the movement prevention structure is a structure in which the lubricant distribution member is fixed to the support shaft by crimping.

4. 2. The toroidal type continuously variable transmission according to claim 1, wherein the movement prevention structure is a structure in which a stepped groove is formed in the support shaft along a circumferential direction, and the lubricant distribution member is crimped and fixed to the stepped groove.

5. The toroidal type continuously variable transmission according to claim 3 or 4, characterized in that in the crimped structure, the lubricant distribution member is shrink-fitted to the support shaft, or the support shaft is cold-fitted to the lubricant distribution member.

6. 2. The toroidal type continuously variable transmission according to claim 1, characterized in that the movement prevention structure is a structure in which a protruding member fitted into a recess formed on the outer periphery of the support shaft so as to protrude from the outer periphery abuts against an end face of the lubricating oil distribution member on the power roller side.

7. 7. The toroidal type continuously variable transmission according to claim 6, wherein the recess is a circumferential groove formed continuously along an outer circumferential direction of the support shaft, and the protruding member is a retaining ring fitted into the circumferential groove.

8. 8. The toroidal type continuously variable transmission according to claim 6 or 7, wherein the lubricant distribution member is fixed to the support shaft by shrink fitting, or the support shaft is fixed to the lubricant distribution member by cold fitting.

9. 9. The toroidal type continuously variable transmission according to claim 1, wherein the lubricant distribution member is formed of a metal having a thermal expansion coefficient equal to or close to that of the support shaft.

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