JP2018084282A5 - - Google Patents

Description

Toroidal continuously variable transmission

  The present invention relates to an improvement of a toroidal continuously variable transmission that is used as an automatic transmission device for generators used in, for example, aircrafts, various industrial machines such as pumps, vehicles (automobiles), and construction machines. .

  The use of a toroidal-type continuously variable transmission as a transmission for an automobile is described in publications such as Patent Document 1 and is partially implemented, and is well known. Further, a structure in which the adjustment range of the gear ratio is widened by combining a toroidal type continuously variable transmission and a planetary gear mechanism is described in publications such as Patent Document 2 and has been widely known.

  FIG. 4 shows an example of a conventional toroidal continuously variable transmission described in each of the above-mentioned patent documents. In the case of this conventional structure, a pair of input-side discs 2a and 2b are disposed around the portions near both ends in the axial direction of the input rotating shaft 1 and axial side surfaces (inner side surfaces) each having a toroidal curved surface having an arcuate cross section. Are supported via ball splines 3 and 3 in a state of facing each other. As a result, the pair of input side disks 2a and 2b are configured to be able to move far and near and to rotate in synchronization with each other via the input rotation shaft 1. Further, an output cylinder 4 is supported around an intermediate portion in the axial direction of the input rotary shaft 1 so as to be able to rotate relative to the input rotary shaft 1. Further, an output gear 5 is fixed to the outer peripheral surface of the output cylinder 4 at the center in the axial direction, and a pair of output side disks 6 and 6 are rotated at both ends in the axial direction in synchronization with the output cylinder 4. I support it. Further, in this state, the axial side surfaces of the output side disks 6 and 6, each of which is a toroidal curved surface having an arc cross section, are opposed to the axial side surfaces of the input side disks 2 a and 2 b.

Also, a plurality of power rollers 7 and 7 each having a partially spherical convex surface are sandwiched between the input disks 2a and 2b and the output disks 6 and 6. These power rollers 7 and 7 are rotatably supported by trunnions 8 and 8, and rotate with the rotation of both input side disks 2 a and 2 b, while the both input side disks 2 a and 2 b rotate the both Power is transmitted to the output side disks 6 and 6. That is, when the toroidal continuously variable transmission is operated, the input shaft 2a on one side (left side in FIG. 4) is rotationally driven by the drive shaft 9 via the mechanical pressing device 10. As a result, the pair of input-side disks 2a and 2b supported on the axially opposite ends of the input rotating shaft 1 rotate synchronously while being pressed toward each other. The rotation is transmitted to the output side disks 6 and 6 through the power rollers 7 and 7 and is taken out from the output gear 5.
Or, contrary to the above description, the power of the drive source is input to the inner disk provided at the position of the both output side disks 6, 6 and a pair of positions provided at the positions of the both input side disks 2a, 2b. It can also be configured to extract power from the outer disk.

  Preload springs 11a and 11b are provided in the vicinity of both end portions in the axial direction of the input rotary shaft 1 at positions where the both input side disks 2a and 2b are sandwiched from both sides in the axial direction. Even when the pressing device 10 is not in operation (when the drive shaft 9 is stopped), the peripheral surfaces of the power rollers 7 and 7 and the inner surfaces of the input side and output side disks 2a, 2b, 6 are provided. The surface pressure of the rolling contact part (traction part) is secured to the minimum necessary. Therefore, these rolling contact portions start power transmission without causing excessive slip immediately after the start of operation of the toroidal continuously variable transmission.

  By the way, the elasticity for securing the necessary minimum surface pressure can be obtained by the preload spring 11 a disposed on the inner diameter side of the pressing device 10. A preload spring 11b disposed between a loading nut 12 screwed to one axial end portion (tip portion) of the input rotary shaft 1 and the outer surface of the input side disk 2b is applied when the pressing device 10 is suddenly operated. It can alleviate the impact and can be omitted. Therefore, in order to reduce the number of parts and improve the assembly work efficiency, the preload spring is omitted from between the loading nut screwed to one axial end of the input rotation shaft and the outer surface of the input side disk. A structure has been proposed in which the input-side disk is supported relative to the input rotation shaft so as not to be relatively rotatable by spline engagement without using a ball spline (see, for example, Patent Document 3). In addition, instead of providing a loading nut, an outward flange-like flange is provided at the tip of the input rotation shaft, or a structure called a cotter for locking an engagement ring at the tip of the input rotation shaft is also known. .

  In any structure, the input side disk is formed by spline-engaging the male spline part provided on the outer peripheral surface of the axial end of the input rotating shaft and the female spline part provided in the center hole of the input side disk. The spline engagement portion between the male spline portion and the female spline portion is supported on the input disk by the pressing force of the power roller. Not only is stress due to elastic deformation easily concentrated, but also fretting wear is likely to occur due to a gap existing in the spline engaging portion.

JP 2003-214516 A JP 2004-169719 A JP 2003-139209 A

  In view of such circumstances, the present inventors provided an outer cylindrical surface portion 15 in the center hole 13 of the input side disk 2c adjacent to the female spline portion 14 as shown in FIG. An inner cylindrical surface portion 17 is provided on the outer peripheral surface of the rotating shaft 1a so as to be adjacent to the male spline portion 16, and the female spline portion 14 and the male spline portion 16 are spline-engaged, and the outer cylindrical surface portion 15 and the The structure in which the inner cylindrical surface portion 17 is fitted over the entire length in the axial direction with an interference fit was considered first. Further, in this state, the disc-side step surface 18 provided in the center hole 13 of the input-side disc 2c and the shaft-side step surface 19 provided on the outer peripheral surface of the input rotating shaft 1a are brought into contact in the axial direction. According to such a structure, the fitting portion between the outer cylindrical surface portion 15 and the inner cylindrical surface portion 17 can improve the support rigidity of the input disk 2c with respect to the input rotating shaft 1a. Generation of stress concentration and fretting wear at joints can be suppressed.

However, the structure shown in FIG. 5 as described above still has room for improvement from the viewpoint of improving the assembly work efficiency of the toroidal-type continuously variable transmission.
That is, when the input side disk 2c is assembled around the input rotary shaft 1a, the outer cylindrical surface portion 15 and the inner cylinder are connected before the female spline portion 14 and the male spline portion 16 are spline-engaged. The surface portion 17 is fitted with an interference fit. For this reason, the operation | work which adjusts the phase of the said female spline part 14 and the said male spline part 16 may become difficult. In order to solve such a problem, for example, as shown in FIG. 6, the axial length α from the disk-side step surface 18 to one axial end portion of the female spline portion 14a is set as follows. Although it is conceivable that the length of the surface portion 17 is longer than the axial length β up to the other end portion in the axial direction, when such a configuration is simply adopted, the input side disk 2c is increased in size. It will cause problems.
In view of the circumstances as described above, the present invention has a structure capable of suppressing the occurrence of fretting wear at the spline engaging portion, and can improve the assembly work efficiency without increasing the size of the outer disk. This invention was invented to realize the structure of the step transmission.

The toroidal continuously variable transmission of the present invention includes a rotating shaft, a pair of outer disks, an inner disk, and a plurality of power rollers.
The rotating shaft has a male spline portion, a shaft-side step surface facing the other end side in the axial direction, and a large-diameter inner side in the order from one end side to the other end side in the axial end portion of the outer peripheral surface. A fitting surface portion and an inner fitting surface portion having a small-diameter inner fitting surface portion whose outer diameter dimension is smaller than that of the large-diameter inner fitting surface portion are provided.
The pair of outer disks rotate in synchronization with the rotating shaft on both axial sides of the rotating shaft in a state in which the axial side surfaces, which are toroidal curved surfaces each having a circular arc cross section, face each other. It is possible to support each of the rotating shafts.
In addition, the inner disk has a rotating shaft around an axially intermediate portion of the rotating shaft in a state in which both axial side surfaces which are toroidal curved surfaces having an arcuate cross section are opposed to the axial side surfaces of the outer disks. It is supported so as to be capable of relative rotation with respect to, and is constituted by one or a pair of elements.
Further, each of the plurality of power rollers is rotatably supported by a support member (for example, trunnion), and each peripheral surface formed as a partial spherical convex surface is formed on the pair of axially opposite side surfaces of the inner disk and the pair of power rollers. It is in contact with the axial side surface of the outer disk.
Also, one outer disk provided on one axial end side of the pair of outer disks has a small-diameter outer fitting surface portion on the inner peripheral surface (center hole) in order from the other axial end side to the one end side. And an outer fitting surface portion having a large-diameter outer fitting surface portion having a larger inner diameter than the small-diameter outer fitting surface portion, a disc-side step surface facing one end in the axial direction, and an inscribed circle than the outer fitting surface portion. Female spline portions each having a large diameter are provided. The female spline portion is spline-engaged with the male spline portion while the disc-side step surface is in contact with the shaft-side step surface, and the large-diameter outer fitting surface portion is The inner fitting surface is fitted (press-fit) with an interference fit, and the small-diameter outer fitting surface is fitted (press-fit) with the small-diameter inner fitting surface.
Further, when a pressing device is additionally provided, the pressing device is provided between the other outer disk provided on the other axial end side of the pair of outer disks and the rotating shaft. Then, the other outer disk is pressed toward one axial end side (one outer disk). As such a pressing device, a mechanical pressing device incorporating a loading cam or a hydraulic pressing device including a hydraulic cylinder and a piston can be used.

  When carrying out the present invention as described above, for example, as in the invention described in claim 2, the shaft from one axial end portion of the female spline portion to one axial end portion of the large-diameter outer fitting surface portion. The direction dimension is made larger than the axial dimension from the other axial end of the male spline part to the other axial end of the large-diameter inner fitting surface part. In addition, the axial dimension from one axial end of the female spline portion to one axial end of the small-diameter outer fitting surface portion, and the axial direction of the small-diameter inner fitting surface portion from the other axial end of the male spline portion. It is larger than the axial dimension to the other end.

According to the toroidal-type continuously variable transmission of the present invention having the above-described configuration, it is possible to prevent fretting wear from occurring at the spline engaging portion and to perform assembly work without increasing the size of the outer disk (one). Efficiency can be improved.
That is, in the case of the present invention, as an outer fitting surface portion provided in the center hole of the outer disk, a large-diameter outer fitting surface portion at one axial end side portion and a small-diameter outer fitting surface portion at the other axial end portion. Is used. And among the inner fitting surface portions provided on the outer peripheral surface of the rotating shaft, the large diameter outer fitting surface portion is fitted into the large diameter inner fitting surface portion of the one axial end side portion and the other axial end portion is fitted. The small-diameter outer fitting surface portion is fitted to the small-diameter inner fitting surface portion of the side portion by an interference fit.
Thus, in the case of the present invention, the outer disk is not only spline-engaged with the rotating shaft, but is also fitted (externally fitted) by interference fitting at least at two positions in the axial direction. Further, the support rigidity of the outer disk with respect to the rotating shaft can be improved. For this reason, it can suppress that fretting wear arises in a spline engaging part.
Further, in the case of the present invention, when the outer disk is assembled from the other axial end around the rotation shaft, the large-diameter outer fitting surface portion of the outer fitting surface portions is inserted into the inner fitting. The large-diameter inner side where the large-diameter outer fitting surface part is provided in the axial one end side part is not required to be fitted into the small-diameter inner fitting surface part provided in the other axial-side part of the mating surface part. The outer disk is moved to one end in the axial direction until it is fitted to the fitting surface or until the small-diameter outer fitting surface is fitted to the small-diameter inner fitting surface provided at the other axial end portion. You can make it. Therefore, according to the present invention, when the fitting occurs between the outer fitting surface portion and the inner fitting surface portion, the axial position of the outer disk with respect to the rotating shaft is determined as the outer fitting surface portion and the inner fitting. Compared to the case where the mating surface portion is a cylindrical surface that is not changed in diameter in the axial direction, it can be shifted to one end in the axial direction. In this way, even if the axial dimension of the female spline portion is lengthened to the extent that the axial position where the fitting occurs is shifted (even if the axial dimension is shortened), the outer fitting is performed. The female spline portion can be spline engaged with the male spline portion before the mating surface portion and the inner fitting surface portion are fitted. That is, before the outer fitting surface portion and the inner fitting surface portion are fitted with an interference fit, the work of aligning the phases of the female spline portion and the male spline portion can be performed. As a result, in the case of the present invention, it is possible to improve the assembly work efficiency of the toroidal type continuously variable transmission without increasing the size of the outer disk more than necessary.

Sectional drawing of the toroidal type continuously variable transmission which shows an example of embodiment of this invention. The A section enlarged view of FIG. 1 similarly. It is sectional drawing for demonstrating the assembly operation | work of an input side disk similarly, (A) has shown the state in the middle of an assembly, and (B) has shown the assembly completion state. Sectional drawing which shows the toroidal type continuously variable transmission of conventional structure. Sectional drawing which shows the structure which the present inventors considered previously regarding the support structure of the input side disk with respect to an input rotating shaft. Sectional drawing which shows the example of improvement similarly.

[Example of Embodiment]
1 to 3 show an example of an embodiment of the present invention. The toroidal-type continuously variable transmission 20 of this example is a transmission that is used, for example, for an aircraft generator. Each of the input rotary shaft 1b corresponding to the rotary shaft described in the claims, A pair of input side disks 2d and 2e corresponding to the outer disk described in the range, an output side disk 6a corresponding to the inner disk described in the claims, a plurality of power rollers 7 and 7, and not shown A plurality of trunnions and a hydraulic pressing device (loading device) 10a are provided.

The input rotary shaft 1b is supported on the upper side of the actuator case 21 through a pair of support columns 22 and 22 and the output side disk 6a so as to be rotatable only. Specifically, the input rotary shaft 1b is configured such that the output-side disk 6a is rotatably supported by thrust angular ball bearings 23 and 23 on support ring portions provided at intermediate portions of the support columns 22 and 22, respectively. Is supported by a pair of radial needle bearings 24, 24 in a rotatable manner.
The "axial direction" in the present specification and claims, unless otherwise indicated, refers to the axial direction of the entering Chikarakai rotating shaft 1b, refer to the left-right direction in FIGS. Moreover, in the case of this example, the right side of FIGS. 1-3 which is the front end side of the said input rotating shaft 1b is equivalent to the axial direction one end side of a claim. On the contrary, the left side of FIGS. 1 to 3 which is the base end side of the input rotary shaft 1b corresponds to the other end side in the axial direction of the claims.

  The two input-side disks 2d and 2e are arranged near the both ends in the axial direction of the input rotary shaft 1b in a state where the axial side surfaces (inner side surfaces) each of which is a toroidal curved surface having an arc cross section are opposed to each other. In addition, it is supported so as to be able to rotate in synchronism with the input rotating shaft 1b and to be able to move far and near.

For this purpose, of the two input side disks 2d and 2e, the input side disk 2d provided on the left side in FIG. 1, which is the other axial end side (base end side) of the input rotary shaft 1b, is pressed. through a cylinder 25 constituting a device 10a, to allow a slight displacement in the axial direction, and, to enable rotation in synchronization with the input rotary shaft 1b, it is supported on the input Chikarakai rotating shaft 1b. The cylinder 25 is configured by coupling and fixing an outer peripheral edge portion of the inner diameter side cylinder element 26 and an inner peripheral edge portion of the outer diameter side cylinder element 27, of which the inner diameter side cylinder element 26 is connected to the input side. The male spline part formed in the axial direction other end part vicinity of the outer peripheral surface of the rotating shaft 1b is engaged with the spline.

  Further, a locking groove 28 is formed in the other end portion in the axial direction of the input rotary shaft 1b than the portion where the inner diameter side cylinder element 26 is fitted, and the locking groove 28 is locked in the locking groove 28. A ring (cotter) 29 is locked. Then, one axial end surface of the locking ring 29 is abutted against the other axial end surface of the inner diameter side portion of the inner diameter side cylinder element 26 so that the cylinder 25 moves away from the input side disk 2d (see FIG. 1). To the left). Accordingly, the inner diameter side cylinder element 26 can be transmitted to the portion near the other end in the axial direction of the input rotating shaft 1b, and can be transmitted while being prevented from being displaced toward the other end in the axial direction. It has been fitted outside.

  The locking ring 29 is formed by combining a plurality of (for example, 2 to 4) partial arc-shaped elements in the circumferential direction. The locking ring 29 is configured. Further, in order to prevent a plurality of elements constituting the locking ring 29 from coming out radially outward from the locking groove 28, the periphery of each of these elements is covered with a restraining ring 30. In the case of the illustrated structure, the restraining ring 30 is rotationally driven by a power source such as an engine, and the driving torque transmitted to the restraining ring 30 is transmitted via the cylinder 25 to the input rotary shaft 1b and It is configured to transmit to the input side disk 2d.

  Further, two piston plates 31 a and 31 b are assembled in the cylinder 25. A hydraulic chamber 33a is provided between a portion between the piston plate 31a on the other axial end side and the bottom plate portion 32 of the cylinder 25 and a portion between the piston plate 31b on the one axial end side and the input side disk 2d. , 33b constitutes the double piston type pressing device 10a. Then, by introducing a predetermined hydraulic pressure into each of the hydraulic chambers 33a and 33b, the input side disk 2d on the other end side in the axial direction is directed toward the input side disk 2c on the one end side in the axial direction, and the hydraulic pressure is reduced. It can be pressed with a force according to the size.

On the other hand, one of the two input-side disks 2d and 2e, which is provided on the right side of FIG. 1 that is one end side (tip side) in the axial direction of the input rotation shaft 1b. input side disk 2e corresponding to the outer disc, so as not to displacement of a direction away from the input side disk 2d in the axial direction one end side, and, to enable rotation in synchronization with the input rotary shaft 1b, the input and it is supported by the rotation axis 1b. For this reason, in the case of this example, the portion closer to one end in the axial direction of the input rotary shaft 1b is arranged in the order from the other end side in the axial direction to the one end side (from left to right in FIGS. The large-diameter shaft portion 35 is configured in a stepped shape in which the shaft-side step surface 36 is continuous. Of these, the outer peripheral surface of the small-diameter shaft portion 34 is the inner fitting surface portion 37 described in the claims. Further, a male spline portion 38 having an outer diameter dimension larger than that of the remaining portion of the large diameter shaft portion 35 is provided at an axially intermediate portion of the large diameter shaft portion 35. In the illustrated example, a relief groove 39 that is recessed inward in the radial direction is provided over the entire circumference in a portion of the large-diameter shaft portion 35 that is adjacent to one end of the male spline portion 38 in the axial direction. ing. Further, the shaft side step surface 36 exists on a virtual plane orthogonal to the central axis of the input rotation shaft 1b.

Further, the center of the input side disk 2e is for inserting the entering-Chikarakai rotation axis 1b, the center hole 40 that penetrates in the axial direction is formed. The center hole 40 has a small-diameter hole portion 41 and a medium-diameter hole portion 42 that are continued from the other end side in the axial direction to one end side (from left to right in FIGS. The medium-diameter hole portion 42 and the large-diameter hole portion 44 are configured in a stepped shape in which the disk-side flat surface 45 is continuous. In addition, a female spline portion 46 that can be spline-engaged with the male spline portion 38 is provided in an intermediate portion in the axial direction of the medium diameter hole portion 42. Further, the inner peripheral surface of the small-diameter hole portion 41 is an outer fitting surface portion 47 having an inner diameter dimension smaller than the diameter of the inscribed circle of the female spline portion 46. The disk-side step surface 43 and the disk-side flat surface 45 exist on a virtual plane orthogonal to the central axis of the input-side disk 2e.

In the assembled state of the toroidal-type continuously variable transmission 20, the shaft-side step surface 36 formed on the outer peripheral surface of the input rotary shaft 1b and the disk-side step surface 43 formed on the inner peripheral surface of the input-side disc 2e are pivoted. by to abut against the direction, in a state which attained positioning in the axial direction of the input side disk 2e for the entering Chikarakai rotating shaft 1b, and said male spline section 38 and the female spline section 46 causes splined The inner fitting surface portion 37 and the outer fitting surface portion 47 are fitted (press-fit, inlay fitting) by interference fitting. With such a configuration, the input-side disk 2e is rotated in synchronization with the input rotation shaft 1b in a state in which the input-side disk 2e is prevented from being displaced toward one end in the axial direction with respect to a portion near one end of the input rotation shaft 1b. I support it as possible.

In particular, in the case of this example, the structure of the fitting portion 48 between the inner fitting surface portion 37 and the outer fitting surface portion 47 is designed in order to improve the assembly work efficiency of the toroidal dull type continuously variable transmission 20. Devised as follows.
That is, in the case of this example, the inner fitting surface portion 37 is not a cylindrical surface whose outer diameter dimension does not change in the axial direction, and the outer diameter dimension is varied according to the axial position. Specifically, a large-diameter inner fitting surface portion 49 is provided on one end side in the axial direction of the inner fitting surface portion 37, and an outer side of the large-diameter inner fitting surface portion 49 is provided on the other end side in the axial direction. A small-diameter inner fitting surface portion 50 having a small diameter is provided. Further, an inner side having an outer diameter smaller than that of the small-diameter inner fitting surface portion 50 at an intermediate portion in the axial direction of the inner fitting surface portion 37 (a portion between the large-diameter inner fitting surface portion 49 and the small-diameter inner fitting surface portion 50). An escape portion 51 is provided. The outer peripheral surfaces of the large-diameter inner fitting surface portion 49 and the small-diameter inner fitting surface portion 50 have a cylindrical surface shape whose outer diameter does not change in the axial direction.

  Also, the outer fitting surface portion 47 is not a cylindrical surface whose inner diameter dimension does not change in the axial direction, but the inner diameter dimension is varied according to the axial position. Specifically, a small-diameter outer fitting surface portion 53 is provided on the other end portion in the axial direction of the outer fitting surface portion 47, and the inner diameter dimension is smaller than that of the small-diameter outer fitting surface portion 53 on the one axial end portion. A large large-diameter outer fitting surface portion 52 is provided. Further, an outer side having an inner diameter dimension larger than that of the large-diameter outer fitting surface portion 52 at an intermediate portion in the axial direction of the outer fitting surface portion 47 (a portion between the large-diameter outer fitting surface portion 52 and the small-diameter outer fitting surface portion 53). An escape portion 54 is provided. The inner peripheral surfaces of the large-diameter outer fitting surface portion 52 and the small-diameter outer fitting surface portion 53 have a cylindrical surface shape whose outer diameter dimension does not change in the axial direction. Further, the inner diameter dimension of the large-diameter outer fitting surface portion 52 is larger than the outer diameter dimension of the small-diameter inner fitting surface portion 50 provided in the other axial end portion of the inner fitting surface portion 37. It is slightly smaller than the outer diameter of the large-diameter inner fitting surface portion 49 provided at one end portion in the direction. On the other hand, the inner diameter dimension of the small-diameter outer fitting surface portion 53 is slightly smaller than the outer diameter dimension of the small-diameter inner fitting surface portion 50 provided at the other axial end portion of the inner fitting surface portion 37. small.

  Further, the output side disk 6a is supported around the intermediate portion in the axial direction of the input rotation shaft 1b so as to be able to rotate relative to the input rotation shaft 1b. In this state, both side surfaces (outer surfaces) in the axial direction of the output side disk 6a are opposed to side surfaces in the axial direction of the both input side disks 2d and 2e. A plurality of power rollers 7 and 7 are sandwiched between the input side disks 2d and 2e and the output side disk 6a. The power rollers 7 and 7 transmit power from the input disks 2d and 2e to the output disk 6a while rotating with the rotation of the input disks 2d and 2e.

In order to assemble the toroidal type continuously variable transmission 20 of the present example having the above-described configuration, the input rotary shaft 1b of the input side disk 2e, the output side disk 6a, and the input side disk 2d are sequentially arranged. after assembling the other axial end side of the input Chikarakai rotating shaft 1b around the portion between the input side disk 2e and the output side disks 6a, between the input side disk 2d before the force side disk 6a The power rollers 7 and 7 are disposed in the intermediate portion, respectively. Then, the locking of the pressing device 10a, assembled from the axial direction other end of the input Chikarakai rotating shaft 1b around the input rotation axis 1b, in the axial direction near the other end portion of the entering Chikarakai rotating shaft 1b The toroidal type continuously variable transmission 20 of this example is obtained by fixing the ring 29 and the holding ring 30.

Particularly in the case of this example, the assembly work of the input side disk 2e with respect to the input rotating shaft 1b is performed as follows.
First, as shown in FIG. 3A, the input side disk 2e is moved to one end side in the axial direction, and the large side provided at one end part in the axial direction of the center hole 40 of the input side disk 2e. the radially outer side fitting surface 52, without causing fitted to the small-diameter inner fitting surface 50 of the entering Chikarakai rotating shaft 1b, passing around the small-diameter inner engagement surface 50 on one axial end. Then, in a state where the large-diameter outer fitting surface portion 52 is positioned around the inner escape portion 51, it is between the one axial end portion of the female spline portion 46 and the other axial end portion of the male spline portion 38. An axis larger than the axial gap A between the axial end of the large-diameter outer fitting surface portion 52 and the other axial end of the large-diameter inner fitting surface portion 49 while having an axial clearance A. An axial gap C larger than the axial gap A between the axial gap B and the axial end of the small-diameter outer fitting surface portion 53 and the other axial end of the small-diameter inner fitting surface portion 50, respectively. To exist. In the case of this example, the dimensions of each part of the input rotary shaft 1b and the input side disk 2e are regulated so that the axial gaps A, B, C having such a dimensional relationship are formed. For example, the axial direction from one axial end portion of the female spline portion 46 to one axial end portion of the large-diameter outer fitting surface portion 52 so that the axial clearance A is smaller than the axial clearance B. The dimension X1 is larger than the axial dimension Y1 from the other axial end of the male spline portion 38 to the other axial end of the large-diameter inner fitting surface portion 49 (X1> Y1). Further, an axial dimension X2 from one axial end portion of the female spline portion 46 to one axial end portion of the small-diameter outer fitting surface portion 53 is set so that the axial clearance A becomes smaller than the axial clearance C. The axial dimension Y2 from the other axial end of the male spline portion 38 to the other axial end of the small-diameter inner fitting surface portion 50 is larger (X2> Y2).

  In the case of this example, the input side disk 2e is rotated relative to the input rotation shaft 1b with the large-diameter outer fitting surface portion 52 positioned around the inner escape portion 51. Thus, the male spline portion 38 and the female spline portion 46 are phase-matched.

  Then, in a state where the phases of the male spline portion 38 and the female spline portion 46 are matched, the input side disk 2e is further moved toward the one end side in the axial direction. Thereby, first, the male spline portion 38 and the female spline portion 46 are spline-engaged. Subsequently, the large-diameter inner fitting surface portion 49 and the large-diameter outer fitting surface portion 52 are fitted by an interference fit, and the small-diameter inner fitting surface portion 50 and the small-diameter outer fitting surface portion 53 are fitted by an interference fit. Fit. The timing for fitting the large-diameter inner fitting surface portion 49 and the large-diameter outer fitting surface portion 52 and the timing for fitting the small-diameter inner fitting surface portion 50 and the small-diameter outer fitting surface portion 53 are as follows. By adjusting the sizes of the axial gaps B and C, it is possible to make them simultaneously, or to make either one faster than the other. In the case of this example, when the male spline portion 38 and the female spline portion 46 are spline-engaged, the inner fitting surface portion 37 and the outer fitting surface portion 47 are loosely fitted. Therefore, since the centering can be performed by this portion, the work of engaging the spline can be facilitated.

According to the toroidal-type continuously variable transmission 20 of the present example having the above-described configuration, it is possible to suppress the occurrence of fretting wear in the spline engaging portion 55, and without increasing the size of the input side disk 2e. The assembly work efficiency can be improved.
That is, in the case of this example, as the outer fitting surface portion 47 provided in the center hole 40 of the input side disk 2e, the large-diameter outer fitting surface portion 52 at one end portion in the axial direction and the other end portion portion in the axial direction. The thing which has the small diameter outer fitting surface part 53 is used. Of the inner fitting surface portion 37 provided on the outer peripheral surface of the input rotary shaft 1b, the large-diameter outer fitting surface portion 52 is fitted into the large-diameter inner fitting surface portion 49 at one end in the axial direction by an interference fit. At the same time, the small-diameter outer fitting surface portion 53 is fitted into the small-diameter inner fitting surface portion 50 at the other end portion in the axial direction by an interference fit. Thus, in the case of this example, not only the input side disk 2e is spline-engaged with the input rotary shaft 1b, but also fitted by an interference fit at two positions separated in the axial direction (outside). Therefore, the support rigidity of the input side disk 2e with respect to the input rotation shaft 1b can be improved. For this reason, it is possible to suppress fretting wear from occurring in the spline engaging portion 55.

Further, in the case of this example, when the input side disk 2e is assembled from the other end side in the axial direction around the input rotary shaft 1a, the large-diameter outer fitting surface portion of the outer fitting surface portion 47. 52 does not need to be fitted to the small-diameter inner fitting surface portion 50 provided at the other axial end portion of the inner fitting surface portion 37, and the large-diameter outer fitting surface portion 52 is disposed at one axial end side. The small-diameter outer fitting surface portion 53 is fitted to the small-diameter inner fitting surface portion 50 provided at the other end portion in the axial direction. The input disk 2e can be moved to one axial end. Therefore, according to the toroidal-type continuously variable transmission 20 of the present example, the input-side disk with respect to the input rotary shaft 1a when the outer fitting surface portion 47 and the inner fitting surface portion 37 are fitted. The axial position of 2e can be shifted to the one end side in the axial direction as compared with the case where the outer fitting surface portion and the inner fitting surface portion are made cylindrical surfaces with the diameter dimension not changed over the axial direction. In this way, even if the axial dimension of the female spline portion 46 is lengthened to the extent that the axial position where the fitting occurs is shifted, the outer side is reduced. The female spline portion 46 can be spline-engaged with the male spline portion 38 before the fitting surface portion 47 and the inner fitting surface portion 37 are fitted with an interference fit. That is, prior to said outer fitting surface 47 and the inner fitting surface 37 is fitted with an interference fit, be carried out the task of matching the phases of the female spline section 4 6 and the male spline section 38 it can. As a result, in this example, the assembly work efficiency of the toroidal type continuously variable transmission 20 can be improved without increasing the size of the input side disk 2e more than necessary.

  Further, in the case of the present example, the female spline portion 46 is formed in the axially middle portion or the portion closer to one end (medium diameter hole portion 42) of the input side disc 2e. The thickness dimension (thickness) in the radial direction of 2e tends to become thicker toward the one end side in the axial direction due to the axial side surface (the other end surface in the axial direction) being a toroidal curved surface having a circular arc cross section. It is in. For this reason, in the case of this example, the female spline portion 46 is formed in a portion of the input side disk 2e having a sufficiently large radial thickness dimension. Regardless of the stress concentration associated with the operation of the machine 20, it is possible to effectively prevent damage such as deformation.

  The present invention is not limited to the half toroidal type as shown in the figure, and can be implemented by a full toroidal type toroidal continuously variable transmission. Moreover, when implementing this invention, about the structure of an outer fitting surface part and an inner fitting surface part, it is not limited to the structure of embodiment as mentioned above. That is, with regard to the outer fitting surface portion, a large-diameter outer fitting surface portion is provided at one end portion in the axial direction, and a small-diameter outer fitting having a smaller inner diameter than the large-diameter outer fitting surface portion at the other axial end portion. It suffices if the surface portion is provided, and it is not always necessary to provide the outer clearance portion between the large-diameter outer fitting surface portion and the small-diameter outer fitting surface portion. Also, with respect to the inner fitting surface portion, a large-diameter inner fitting surface portion is provided at one end portion in the axial direction, and a small-diameter inner fitting having a smaller outer diameter than the large-diameter inner fitting surface portion is provided at the other axial end portion. It is sufficient if the mating surface portion is provided, and it is not always necessary to provide the inner relief portion between the large-diameter inner fitting surface portion and the small-diameter inner fitting surface portion. Further, between the large-diameter outer fitting surface portion and the small-diameter outer fitting surface portion, there is provided an intermediate-diameter outer fitting surface portion whose inner diameter is intermediate between the large-diameter outer fitting surface portion and the small-diameter outer fitting surface portion. A medium-diameter outer fitting surface portion is provided between the large-diameter inner fitting surface portion and the small-diameter inner fitting surface portion, and the outer diameter dimension is intermediate between the large-diameter inner fitting surface portion and the small-diameter inner fitting surface portion. It is also possible to employ a configuration in which the inner side fitting surface portion is fitted with an interference fit. In the above embodiment, the description has been given of the case where the pair of outer disks are input disks for inputting power, and the inner disks are output disks for outputting power. In some cases, on the contrary, the inner disk may be an input side disk for inputting power, and the pair of outer disks may be an output side disk for outputting power.

DESCRIPTION OF SYMBOLS 1, 1a, 1b Input rotary shaft 2a, 2b, 2c, 2d, 2e Input side disk 3 Ball spline 4 Output cylinder 5 Output gear 6, 6a Output side disk 7 Power roller 8 Trunnion 9 Drive shaft 10, 10a Pressing device 11a, 11b preload spring 12 loading nut 13 central hole 14,14a female spline portion 15 outer cylindrical surface 16 male spline portion 17 inside cylindrical surface portion 18 the disc-side stepped surface 19 shaft-side stepped surface 20 toroidal type continuously variable transmission 21 actuator case 22 posts 23 Ball bearing 24 Radial needle bearing 25 Cylinder 26 Inner diameter side cylinder element 27 Outer diameter side cylinder element 28 Engagement groove 29 Engagement ring 30 Retaining ring 31a, 31b Piston plate 32 Bottom plate part 33a, 33b Hydraulic chamber 34 Small diameter shaft part 35 Large Diameter shaft part 36 Shaft Step surface 37 Inner fitting surface portion 38 Male spline portion 39 Escape groove 40 Center hole 41 Small diameter hole portion 42 Medium diameter hole portion 43 Disc side step surface 44 Large diameter hole portion 45 Disc side flat surface 46 Female spline portion 47 Outer fitting Face portion 48 Fitting portion 49 Large diameter inner fitting surface portion 50 Small diameter inner fitting surface portion 51 Inner relief portion 52 Large diameter outer fitting surface portion 53 Small diameter outer fitting surface portion 54 Outer relief portion 55 Spline engagement portion