JP6015253B2 - Toroidal continuously variable transmission - Google Patents

Description

  The present invention relates to a toroidal continuously variable transmission that can be used for transmissions of automobiles and various industrial machines.

  For example, a double cavity half-toroidal continuously variable transmission used as an automobile transmission is configured as shown in FIGS. 4 and 5 (two cavities 221 and 222 are shown in FIG. 4). As shown in FIG. 4, an input shaft (center shaft) 1 is rotatably supported inside the casing 50, and two input side disks 2, 2 and two outputs are provided on the outer periphery of the input shaft 1. Side disks 3 and 3 are attached. An output gear 4 is rotatably supported on the outer periphery of the intermediate portion of the input shaft 1. Output side disks 3 and 3 are connected to cylindrical flange portions 4a and 4a provided at the center of the output gear 4 by spline coupling.

  The input shaft 1 is rotationally driven by a drive shaft 22 via a loading cam type pressing device 12 provided between an input side disk 2 and a cam plate 7 located on the left side in the drawing. . The output gear 4 is supported in the casing 50 via a partition wall 13 formed by coupling two members, so that the output gear 4 can rotate around the axis O of the input shaft 1 while the axis O. Directional displacement is prevented.

  The output side disks 3 and 3 are supported by needle bearings 5 and 5 interposed between the input shaft 1 so as to be rotatable about the axis O of the input shaft 1. Further, the left input side disk 2 in the figure is supported on the input shaft 1 via a ball spline 6, and the right side input disk 2 in the figure is splined to the input shaft 1. Rotates with the input shaft 1. Further, a power roller 11 (FIG. 5) is provided between the inner side surfaces (concave surfaces) 2a and 2a of the input side disks 2 and 2 and the inner side surfaces (concave surface; also referred to as traction surface) 3a and 3a of the output side disks 3 and 3. (See below) is rotatably held.

  A step 2b is provided on the inner peripheral surface 2c of the input disk 2 located on the right side in FIG. 4, and the step 1b provided on the outer peripheral surface 1a of the input shaft 1 is abutted against the step 2b. At the same time, the back surface (the right surface in FIG. 4) of the input side disk 2 is abutted against the loading nut 9. Thereby, the displacement of the input side disk 2 in the direction of the axis O with respect to the input shaft 1 is substantially prevented. Further, a disc spring 8 is provided between the cam plate 7 and the flange 1d of the input shaft 1, and this disc spring 8 is a concave surface 2a, 2a, 3a of each disk 2, 2, 3, 3. , 3a and the contact surface between the peripheral surfaces 11a and 11a of the power rollers 11 and 11 are applied with a pressing force.

  FIG. 5 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 5, a pair of trunnions 15, 15 that swing around a pair of pivots 14, 14 that are twisted with respect to the input shaft 1 are provided inside the casing 50. In addition, illustration of the input shaft 1 is abbreviate | omitted in FIG. Each trunnion 15, 15 is formed at a pair of ends formed in the longitudinal direction (vertical direction in FIG. 5) of the support plate portion 16 that supports the power roller 11 in a state of being bent toward the inner surface side of the support plate portion 16. It has the bent wall parts 20 and 20. The bent wall portions 20 and 20 form concave pocket portions P for accommodating the power rollers 11 in the trunnions 15 and 15. Further, the pivot shafts 14 and 14 are concentrically provided on the outer side surfaces of the bent wall portions 20 and 20, respectively.

  A circular hole 21 is formed in the central portion of the support plate portion 16, and the base end portion 23 a of the displacement shaft 23 is supported in the circular hole 21. Then, by swinging each trunnion 15, 15 about each pivot 14, 14, the inclination angle of the displacement shaft (shaft) 23 supported at the center of each trunnion 15, 15 can be adjusted. It has become. In addition, each power roller 11 is rotatably supported via a radial needle bearing 99 around the distal end portion 23b of the displacement shaft 23 protruding from the inner surface of each trunnion 15, 15. 11 is sandwiched between the input disks 2 and 2 and the output disks 3 and 3. In addition, the base end part 23a and the front-end | tip part 23b of each displacement shaft 23 and 23 are mutually eccentric.

  The pivot shafts 14 and 14 of the trunnions 15 and 15 are supported so as to be swingable and displaceable in the axial direction (vertical direction in FIG. 5) with respect to the pair of yokes 23A and 23B. The horizontal movement of the trunnions 15 and 15 is restricted by 23B. Each yoke 23A, 23B is formed in a rectangular shape by pressing or forging a metal such as steel. Four circular support holes 18 are provided at the four corners of each of the yokes 23A and 23B, and the pivot shafts 14 provided at both ends of the trunnion 15 are respectively connected to the support holes 18 via radial needle bearings (bearings) 30. And is swingably supported. In addition, a circular locking hole 19 is provided in the central portion of the yokes 23A and 23B in the width direction (left and right direction in FIG. 4). The inner peripheral surface of the locking hole 19 is a cylindrical surface, and is a spherical post. 64 and 68 are fitted inside. That is, the upper yoke 23A is swingably supported by the spherical post 64 supported by the casing 50 via the fixing member 52, and the lower yoke 23B is supported by the spherical post 68 and the drive for supporting the same. The upper cylinder body 61 of the cylinder 31 is swingably supported.

  The displacement shafts 23 and 23 provided in the trunnions 15 and 15 are provided at positions 180 degrees opposite to the input shaft 1. Further, the direction in which the distal end portion 23b of each of the displacement shafts 23, 23 is eccentric with respect to the base end portion 23a is the same direction as the rotational direction of both the disks 2, 2, 3, 3 (in FIG. (Reverse direction). Further, the eccentric direction is a direction substantially orthogonal to the direction in which the input shaft 1 is disposed. Accordingly, the power rollers 11 and 11 are supported so that they can be slightly displaced in the longitudinal direction of the input shaft 1. As a result, even if each power roller 11, 11 tends to be displaced in the axial direction of the input shaft 1 due to elastic deformation of each component member based on the thrust load generated by the pressing device 12, each component This displacement is absorbed without applying an excessive force to the member.

  Further, 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 24 that is a thrust rolling bearing, and a thrust needle bearing, in order from the outer surface side of the power roller 11. 25. Among these, the thrust ball bearing 24 supports the rotation of each power roller 11 while supporting the load in the thrust direction applied to each power roller 11. Each of such thrust ball bearings 24 includes a plurality of balls (hereinafter referred to as rolling elements) 26, 26, an annular retainer 27 that holds the rolling elements 26, 26 in a freely rolling manner, And an annular outer ring 28. Further, the inner ring raceway of each thrust ball bearing 24 is formed on the outer side surface (large end surface) of each power roller 11, and the outer ring raceway is formed on the inner side surface of each outer ring 28.

  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 a thrust needle bearing 25 supports the thrust load applied to each outer ring 28 from the power roller 11, while the power roller 11 and the outer ring 28 swing around the base end portion 23 a of each displacement shaft 23. Allow.

Further, drive rods (trunnion shafts) 29 and 29 are provided at one end portions (lower end portions in FIG. 5) of the trunnions 15 and 15, respectively, and a drive piston ( Hydraulic pistons) 33, 33 are fixed. Each of the drive pistons 33 and 33 is oil-tightly fitted in a drive cylinder (cylinder body) 31 constituted by an upper cylinder body 61 and a lower cylinder body 62. These and drive pistons 33, 33 and the driving cylinder 31, the respective trunnions 15, 15, the driving device (hydraulic drive) for displacing in the axial direction of the pivot shafts 14, 14 of the trunnions 15, 15 3 2 configure and the Yes.

  In the case of the toroidal continuously variable transmission configured as described above, the rotation of the input shaft 1 is transmitted to the input side disks 2 and 2 via the pressing device 12. Then, the rotation of the input side disks 2 and 2 is transmitted to the output side disks 3 and 3 via the pair of power rollers 11 and 11, and the rotation of the output side disks 3 and 3 is further transmitted to the output gear 4. Is taken out more.

  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. As the drive pistons 33 and 33 are displaced, the pair of trunnions 15 and 15 are displaced in directions opposite to each other. For example, the power roller 11 on the left side in FIG. 5 is displaced to the lower side in the figure, and the power roller 11 on the right side in the figure is displaced to the upper side in the figure. As a result, the peripheral surfaces 11a and 11a of the power rollers 11 and 11 act on contact portions of the input side disks 2 and 2 and the inner side surfaces 2a, 2a, 3a and 3a of the output side disks 3 and 3, respectively. The direction of the tangential force changes. As the force changes, the trunnions 15 and 15 swing (tilt) in opposite directions around the pivots 14 and 14 pivotally supported by the yokes 23A and 23B.

  As a result, the contact position between the peripheral surfaces (traction surfaces) 11a and 11a of the power rollers 11 and 11 and the inner surfaces 2a and 3a changes, and the gear ratio between the input shaft 1 and the output gear 4 changes. To do. Further, when the torque transmitted between the input shaft 1 and the output gear 4 fluctuates and the amount of elastic deformation of each component changes, the power rollers 11 and 11 and the outer rings attached to the power rollers 11 and 11 will be described. 28 and 28 slightly rotate around the base end portions 23a and 23a of the displacement shafts 23 and 23, respectively. Since the thrust needle bearings 25 and 25 exist between the outer side surfaces of the outer rings 28 and 28 and the inner side surfaces of the support plate portions 16 constituting the trunnions 15 and 15, respectively, the rotation is performed smoothly. Is called. Therefore, as described above, the force for changing the inclination angle of each displacement shaft 23, 23 can be small.

  By the way, in recent years, toroidal type continuously variable transmissions tend to be modularized in order to facilitate handling. There is also a demand for downsizing due to restrictions on installation space. When designing a toroidal-type continuously variable transmission, the dimensions of the input side disks 2, 2, the output side disks 3, 3, and the power roller 11 are determined by the required performance. I have to deal with it.

  Conventionally, as shown in FIGS. 6 and 7, for example, when an integrated output side disk 3A in which two output side disks 3 and 3 are integrally formed is used, an outer peripheral end of the integrated output side disk 3A is used. Since the output gear 4 is integrally formed in the part, the outer peripheral diameter becomes large. Therefore, the upper cylinder body 61 of the drive cylinder 31 is scraped to form the recess 100, and the integrated output side disk 3A is formed in the recess 100. The outer peripheral end portion is accommodated to thereby reduce the size.

  Conventionally, as shown in FIG. 8, a piston chamber 102 that houses the drive piston 33 is provided in the upper cylinder body 61. In addition, in order to increase the size (outer diameter) of the pair of drive pistons 33 and increase the pressure receiving area of the pistons, piston chambers are provided in the upper cylinder body 61 and the lower cylinder body 62, respectively. It has been proposed that a pair of drive pistons 33 be offset in the axial direction of the pivot 14 (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2003-4112

  However, if the upper cylinder body 61 is provided with the piston chamber 102, as shown in FIG. 8, the upper cylinder body 61 is scraped to accommodate the outer peripheral end of the integrated output side disk 3A. Is formed, the gap between the recess 100 and the piston chamber 102 becomes thin, and there is a problem that the strength of the upper cylinder body 61 is reduced. If the thickness of the upper cylinder body 61 is increased in order to avoid this problem, the weight of the upper cylinder body 61 increases, leading to an increase in cost and a deterioration in fuel consumption. Further, as shown by a broken line in FIG. 7, if the piston chamber 102 is enlarged in order to increase the diameter of the drive piston 33, it interferes with the recess 100 at the location D, and the diameter of the drive piston 33 cannot be increased. There is.

  The present invention has been made in view of the above circumstances, and even if the cylinder body is provided with a recess or the like, the weight of the cylinder body is not increased and the strength of the hydraulic drive device is not reduced. Provided is a toroidal-type continuously variable transmission capable of providing a piston chamber.

In order to achieve the above object, a toroidal continuously variable transmission according to the present invention includes an input side disk and an output side disk that are supported concentrically and rotatably with their inner surfaces facing each other, and A plurality of power rollers sandwiched between these two disks, and a pair of pivots that are concentrically provided to each other and are twisted with respect to the center axis of the input side disk and the output side disk. A toroidal continuously variable transmission that includes a plurality of trunnions that rotate and rotatably support the power rollers, and a hydraulic drive device that displaces the trunnions in the axial direction of the pivot.
The hydraulic drive device includes a hydraulic piston coupled to the pivot of the trunnion, and a cylinder body that forms a piston chamber that slidably and oil-tightly accommodates the hydraulic piston,
The cylinder body is composed of a first cylinder body located on a side closer to the power roller and a second cylinder body located on a side far from the power roller,
The piston chamber is formed only in the second cylinder body.

In the present invention, the cylinder body has a two-stage configuration of a first cylinder body located on the side closer to the power roller and a second cylinder body located on the side farther from the power roller, and located on the side farther from the power roller. Since the piston chamber is formed only in the second cylinder body , the first cylinder body located on the side close to the power roller is formed with a recess or the like for avoiding interference with other members, A sufficient thickness can be secured between the recess and the piston chamber. For this reason, it is not necessary to make the thickness of the first cylinder body and the second cylinder body thicker than in the past, so that the weight of the cylinder body is not increased.

The said structure of this invention WHEREIN: The recessed part or through-hole for avoiding interference with the outer peripheral edge part of the said output side disk may be formed in the said 1st cylinder body.
Furthermore, the piston chamber of the second cylinder body may extend to a position that overlaps with the concave portion of the first cylinder body. As a result, the size (outer diameter) of the hydraulic piston can be increased, the pressure receiving area of the piston can be increased, the control pressure can be lowered, and fuel consumption can be improved.
In the above configuration of the present invention, a supply oil passage is formed in the first cylinder body, and the lubricant is supplied to the trunnion oil passage for supplying the lubricant to the power roller through the supply oil passage. You may do it. Thereby, the 1st cylinder body in which the piston chamber is not formed can be used effectively.

  According to the present invention, even if the cylinder body is provided with a recess or the like for avoiding interference of other members, the weight of the cylinder body is not increased and the strength is not reduced. A piston chamber can be provided.

It is a figure which shows the toroidal type continuously variable transmission which concerns on the 1st Embodiment of this invention, Comprising: It is sectional drawing which shows a drive cylinder (cylinder body) part. It is a figure which shows the toroidal type continuously variable transmission which concerns on the 2nd Embodiment of this invention, Comprising: It is sectional drawing which shows a drive cylinder (cylinder body) part. It is a figure which shows the toroidal type continuously variable transmission which concerns on the 3rd Embodiment of this invention, Comprising: It is sectional drawing which shows a drive cylinder (cylinder body) part. It is sectional drawing which shows an example of the specific structure of the half toroidal type continuously variable transmission conventionally known. It is sectional drawing which follows the AA line of FIG. It is a figure which shows the conventional toroidal type continuously variable transmission, Comprising: It is sectional drawing which shows the relationship between an integral type output side disk and a drive cylinder. FIG. 6 is a plan view showing the relationship between the integrated output disk and the drive cylinder. It is sectional drawing which follows the BB line of FIG.

Embodiments of the present invention will be described below with reference to the drawings.
The feature of the present invention lies in the structure of the cylinder body, and other configurations and operations are the same as those of the conventional configuration and operations described above. Therefore, in the following, only the features of the present invention will be referred to. The other parts are simply described with the same reference numerals as in FIGS.

FIG. 1 shows a first embodiment of the present invention.
As shown in the figure, in the first embodiment, as in the conventional case of FIGS. 4 to 8, a drive device (hydraulic drive device) 32 for displacing the trunnion 15 in the axial direction of the pivot 14 is A drive piston (hydraulic piston) 33 connected to the pivot 14 of the trunnion 15 and a drive cylinder (cylinder body) 31 are provided. The drive piston 33 is fitted on the outer side of a drive rod (trunnion shaft) 29 fixed to one end of the pivot 14 of the trunnion 15, and is fixed to the nut 104 by the drive rod 29. The drive cylinder 31 includes an upper cylinder body (first cylinder body) 61 located on the side closer to the power roller 11 and a lower cylinder body (second cylinder body) 62 located on the side far from the power roller 11. To two stages. A pair of drive devices 32 are provided in the same cavity (respective cavities 221 and 222), and a total of four drive units 32 are installed as a double cavity half-toroidal continuously variable transmission.

A concave portion 100 is formed in the upper cylinder body 61 of the drive cylinder 31, and the outer peripheral end portion of the integrated output side disk 3A is accommodated in the concave portion 100, thereby interfering with the outer peripheral end portion of the output side disc 3A. Avoid. The lower cylinder body 62 is formed with a piston chamber 102 that slidably and oil-tightly accommodates the drive piston 33. In the piston chamber 102, a circular plate-like recess having a surface facing the upper cylinder body 61 is formed in the lower cylinder body 62, and the opening of the recess is closed by the upper cylinder body 61. It consists of.
Further, a supply oil passage 106 is formed in the upper cylinder body 61, and the lubricant is supplied to the oil passage 108 of the trunnion 15 that supplies the lubricant to the power roller 11 through the supply oil passage 106.
In the figure, symbol S is a seal for maintaining oil tightness.

  In the toroidal type continuously variable transmission configured as described above, the upper cylinder body 61 where the drive cylinder 31 is located on the side closer to the power roller 11 and the lower cylinder body 62 located on the side farther from the power roller 11, Since the piston chamber 102 is formed in the lower cylinder body 62 located on the side far from the power roller 11, the output is integrated with the upper cylinder body 61 located on the side closer to the power roller 11. Even if the recess 100 for avoiding interference with other members such as the side disk 3A is formed, a sufficient thickness can be ensured between the recess 102 and the piston chamber 102. Therefore, it is not necessary to increase the thickness of the upper cylinder body 61 and the lower cylinder body 62 as compared with the conventional case, so that the weight of the drive cylinder 31 is not increased.

  Further, since the lubricating oil is supplied to the oil passage of the trunnion 14 for supplying the lubricating oil to the power roller 11 through the supply oil passage 106 formed in the upper cylinder body 61, the upper cylinder in which the piston chamber 102 is not formed. The body 61 can be used effectively.

FIG. 2 shows a second embodiment of the present invention.
As shown in the figure, in the second embodiment, only the point that the piston chamber 102 of the lower cylinder body 62 extends to a position where it overlaps the concave portion 100 of the upper cylinder body 61 is the first embodiment. Unlike the first embodiment, other configurations are the same as those of the first embodiment.

Even in the toroidal type continuously variable transmission according to the second embodiment, the same effects as those of the first embodiment can be obtained.
Furthermore, in the second embodiment, since the outer diameter of the piston chamber 102 can be increased and the size (outer diameter) of the drive piston 33 can be increased, the pressure receiving area of the drive piston 33 is increased. Therefore, the control pressure can be lowered, thereby improving fuel consumption.

FIG. 3 shows a third embodiment of the present invention.
As shown in the figure, in the third embodiment, a through hole 120 is formed in the upper cylinder body 61 of the drive cylinder 31 instead of the recess 100, and an integrated output side disk is formed in the through hole 120. The outer peripheral end of 3A is accommodated, thereby avoiding interference with the outer peripheral end of the output side disk 3A. Other configurations of the third embodiment are the same as those of the first embodiment.

  Even in the toroidal type continuously variable transmission according to the third embodiment, the same effects as those of the first embodiment can be obtained.

  In each of the above-described embodiments, the recess 100 or the through hole 120 is formed in the upper cylinder body 61 (first cylinder body) in order to avoid interference with the integrated output side disk 3A. In order to avoid interference with other members or for other purposes, the recesses 100 or the through holes 120 may be formed. Further, the recess 100 or the through hole 120 is not necessarily provided in the upper cylinder body 61 (first cylinder body). If the piston chamber 102 is provided in the lower cylinder body 62 (second cylinder body), there is an advantage that the thickness of the upper cylinder body 61 (first cylinder body) can be appropriately reduced as necessary. Because there is.

  The present invention can be applied to various single cavity type and double cavity type half toroidal type continuously variable transmissions.

2 Input side disk 3 Output side disk 11 Power roller 14 Axis 15A Trunnion 31 Drive cylinder (cylinder body)
32 Drive unit (hydraulic drive unit)
61 Upper cylinder body (first cylinder body)
62 Lower cylinder body (second cylinder body)
100 Concave portion 102 Piston chamber 106 Supply oil passage 120 Through hole

Claims (5)

An input-side disk and an output-side disk that are supported concentrically and rotatably with their inner surfaces facing each other, a plurality of power rollers sandwiched between these two disks, and the input-side disk And a plurality of trunnions that are twisted with respect to the central axis of the output-side disk and tilt around a pair of pivots that are concentrically provided to each other and that rotatably support the power rollers, A toroidal continuously variable transmission comprising a hydraulic drive device that displaces the trunnion in the axial direction of the pivot;
The hydraulic drive device includes a hydraulic piston coupled to the pivot of the trunnion, and a cylinder body that forms a piston chamber that slidably and oil-tightly accommodates the hydraulic piston,
The cylinder body is composed of a first cylinder body located on a side closer to the power roller and a second cylinder body located on a side far from the power roller,
A toroidal continuously variable transmission , wherein the piston chamber is formed only in the second cylinder body.   2. The toroidal continuously variable transmission according to claim 1, wherein a recess for avoiding interference with an outer peripheral end of the output side disk is formed in the first cylinder body.   The toroidal continuously variable transmission according to claim 2, wherein the piston chamber of the second cylinder body extends to a position overlapping the concave portion of the first cylinder body.   2. The toroidal continuously variable transmission according to claim 1, wherein a through portion for avoiding interference with an outer peripheral end portion of the output side disk is formed in the first cylinder body.   The supply oil passage is formed in the first cylinder body, and the lubricant is supplied to the trunnion oil passage through which the lubricant is supplied to the power roller. The toroidal-type continuously variable transmission of any one of Claim 4.

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