JP2016003680A - Toroidal continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toroidal continuously variable transmission capable of achieving weight reduction while ensuring the strength of an output-side disc.SOLUTION: A toroidal continuously variable transmission comprises: an input-side disc 2 and an output-side disc 3 provided concentrically and rotatably in a state in which inner side surfaces face each other; and power rollers 11 interposed between the input-side disc 2 and the output-side disc 3, the output-side disc 3 being thicker as being closer to an outside diameter.

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 toroidal continuously variable transmission used as a transmission for an automobile is configured as shown in FIGS. As shown in FIG. 6, an input shaft (shaft) 1 is rotatably supported inside the casing 50, and two input side disks 2, 2 and two output sides are provided on the outer periphery of the input shaft 1. 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. A power roller 11 (see FIG. 7) is rotatable between the inner side surfaces (concave surfaces) 2a, 2a of the input side disks 2, 2 and the inner side surfaces (concave surfaces) 3a, 3a of the output side disks 3, 3. Is sandwiched between.

  A step 2b is provided on the inner peripheral surface 2c of the input side disk 2 located on the right side in FIG. 6, 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. 6) 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. 7 is a cross-sectional view taken along the line AA of FIG. As shown in FIG. 7, a pair of trunnions 15, 15 that swing about 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 a pair of bent wall portions 20, 20 formed at both ends in the longitudinal direction (vertical direction in FIG. 7) of the support plate portion 16 so as to be bent toward the inner surface side of the support plate portion 16. have. 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 center portion of the support plate portion 16, and a base end portion (first shaft 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 23 supported at the center of each trunnion 15, 15 can be adjusted. Each power roller 11 is rotatably supported around the distal end portion 23b of the displacement shaft 23 protruding from the inner surface of each trunnion 15, 15, and each power roller 11, 11 is connected to each input side disk. 2 and 2 and between the output side 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 axially displaceable with respect to the pair of yokes 23A and 23B, respectively. 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 23 </ b> A and 23 </ b> B, and the pivot shafts 14 provided at both ends of the trunnion 15 swing through the radial needle bearings 30. It is supported freely. In addition, a circular locking hole 19 is provided in the central portion of the yokes 23A and 23B in the width direction (left-right direction in FIG. 6). 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 (thrust bearing) 24 that is a thrust rolling bearing is sequentially formed from the outer surface side of the power roller 11. A thrust needle bearing 25 is provided. 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.

  Furthermore, drive rods (trunnion shafts) 29 and 29 are provided at one end portions (lower end portions in FIG. 7) of the trunnions 15 and 15, respectively, and a drive piston ( Hydraulic pistons) 33, 33 are fixed. Each of these drive pistons 33 and 33 is oil-tightly fitted in a drive cylinder 31 constituted by an upper cylinder body 61 and a lower cylinder body 62. The drive pistons 33 and 33 and the drive cylinder 31 constitute a drive device 32 that displaces the trunnions 15 and 15 in the axial direction of the pivots 14 and 14 of the trunnions 15 and 15.

  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 of FIG. 7 is displaced downward in the figure, and the power roller 11 on the right side of FIG. 7 is displaced upward 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 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 11a and 11a of the power rollers 11 and 11 and the inner surfaces 2a and 3a changes, and the rotational speed ratio between the input shaft 1 and the output gear 4 changes. 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, various proposals have conventionally been made for an input side disk and an output side disk used in a toroidal type continuously variable transmission.
For example, in Patent Document 1, a plurality of reinforcing ribs are formed in a radial direction on at least one outer surface of an input side disk and an output side disk, and the radial direction is applied to a portion where the reinforcing ribs are not formed. A toroidal continuously variable transmission is described in which at least one of the input side disk and the output side disk is reduced in weight by making the cross-sectional shape a substantially arc shape.

  Further, in Patent Document 2, a spiral or concentric groove that is connected from the small diameter side to the outer diameter side is formed on the non-traction surface that is the back surface of the input side disk and / or the output side disk. A toroidal continuously variable transmission that can improve the cooling performance of the vehicle and improve the traction performance is described.

  In Patent Document 3, a plurality of reinforcing ribs are provided radially on the antitraction surface of at least one of the input side disk and the output side disk, and lubricating oil is supplied to the space between the reinforcing ribs. Describes a toroidal continuously variable transmission that can effectively cool the entire disk by providing an oil passage that allows lubricating oil to continuously flow from the disk inner diameter side to the disk outer diameter side by centrifugal force associated with the rotation of the disk. Has been.

  Further, Patent Document 4 discloses that the concentration of stress in the spline hole portion of the disk is not increased so much by providing an annular or radially concave groove on the back surface of the input side or output side disk. A toroidal type continuously variable transmission that can effectively prevent the above is described.

  However, these Patent Documents 1 to 4 do not discuss the relaxation of the stress on the back surface or the traction surface immediately below the contact point generated by the pressing force generated at the contact point of the power roller. There is a problem that the weight of the toroidal-type continuously variable transmission increases when attempting to relieve stress at the stress site.

Utility Model Registration No. 2543314 JP-A-11-132304 JP 2004-156758 A JP 2004-44656 A

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a toroidal continuously variable transmission capable of reducing the weight while securing the strength of the output side disk.

  In order to achieve the above object, the toroidal continuously variable transmission of the present invention includes an input side disk and an output side disk provided concentrically and rotatably in a state where the inner side surfaces thereof face each other, In the toroidal-type continuously variable transmission including a power roller sandwiched between the input side disk and the output side disk, the output side disk is thicker toward the outer diameter side. Features.

  In this case, it is preferable that the output side disk has a thickness that is thicker from the inner diameter side than a portion where the stress generated on the traction surface is high, and is thinner toward the outer diameter side.

The toroidal continuously variable transmission according to the present invention includes an input side disk and an output side disk that are concentrically and rotatably provided with their inner side surfaces facing each other, and the input side disk and the output side disk. In the toroidal-type continuously variable transmission having a power roller sandwiched between the side disk and the output side disk, the thickness increases toward the outer diameter side, and a rib is provided on the back surface. A plurality of ribs are provided radially at intervals in the circumferential direction, and the height of each rib increases toward the inner diameter side.
In this case, it is preferable that the thickness of the input side disk becomes thinner toward the outer diameter side.

The toroidal continuously variable transmission according to the present invention includes an input side disk and an output side disk that are concentrically and rotatably provided with their inner side surfaces facing each other, and the input side disk and the output side disk. In the toroidal-type continuously variable transmission having a power roller sandwiched between the side disk and the output side disk, the thickness increases toward the outer diameter side, and a rib is provided on the back surface. A plurality of ribs are provided radially at intervals in the circumferential direction, and the height of each rib increases toward the inner diameter side.
In this case, it is preferable that the thickness of the input side disk becomes thinner toward the outer diameter side.

ADVANTAGE OF THE INVENTION According to this invention, the toroidal type continuously variable transmission which can achieve weight reduction can be provided, ensuring the intensity | strength of an output side disk, and there exists the following effect specifically.
According to the first aspect of the present invention, the thickness of the output side disk increases toward the outer diameter side. Thereby, the stress which generate | occur | produces in the back surface 74 of the contact point vicinity of an outer diameter side can be relieved.
According to the second aspect of the present invention, the output side disk is thicker from the inner diameter side than the portion where the stress generated on the traction surface is high, and is thinner toward the outer diameter side. Thereby, by increasing the section modulus, the stress on the traction surface can be relieved and the weight of the disk can be reduced.
According to the invention of claim 3, the output side disk is thicker toward the outer diameter side, and the rib is provided on the back surface. Thereby, the stress which generate | occur | produces in a traction surface by a bending moment can be relieved.

It is a figure which shows the output side disk of the toroidal type continuously variable transmission which concerns on the 1st Embodiment of this invention, Comprising: It is sectional drawing which shows an upper half. It is a figure which shows the output side disk of the toroidal type continuously variable transmission which concerns on the 2nd Embodiment of this invention, Comprising: It is sectional drawing which shows the upper half. It is a figure which shows the output side disk of the toroidal type continuously variable transmission which concerns on the 3rd Embodiment of this invention, Comprising: It is sectional drawing which shows an upper half. It is a perspective view of the output side disk shown in FIG. It is the figure which applied this invention to the input side disk of a toroidal type continuously variable transmission, Comprising: It is sectional drawing which shows the upper half. 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.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The feature of the toroidal type continuously variable transmission of the present embodiment is the shape of the input side disk and the output side disk, and other configurations and operations are the same as the conventional configurations and operations described above. Only the characteristic part of this embodiment will be described, and the other parts will be simply described with the same reference numerals as those in FIGS.

  FIG. 1 is a half sectional view showing an output side disk 3 of a toroidal type continuously variable transmission according to a first embodiment of the present invention. As shown in FIG. 1, the pressing force F2 generated at the contact point of the output disk 3 with the power roller 11 is larger on the outer diameter side (upper side in FIG. 1) when the input torque is the same. The inner diameter side (lower side in FIG. 1) becomes smaller. For this reason, in the case of the output side disk 3, contrary to the input side disk 2, a large stress is generated on the back surface 74 near the contact point on the outer diameter side. Therefore, in the present embodiment, the stress generated on the back surface 74 in the vicinity of the contact point on the outer diameter side is relieved by changing the thickness T2 of the output side disk in accordance with the pressing force F2 generated at the contact point. . Specifically, the disk thickness T2 on the inner diameter side where the pressing force F2 is small is reduced, and the disk thickness T2 is increased toward the outer diameter side outer diameter side (the side far from the disk axis) where the pressing force F2 increases. To do. As a result, it is possible to reduce the weight while securing the strength of the output side disk 3. Here, the disc thickness T2 refers to the thickness in the axial direction of the disc. The dimension setting relating to the disk thickness T2 is not applied to the cylindrical mounting portion formed at the base end portion of the output side disk 3 in order to mount the output side disk 3. This also applies to other embodiments described later.

  FIG. 2 is a half sectional view showing the output side disk 3 of the toroidal type continuously variable transmission according to the second embodiment of the present invention. When the contact point X of the output side disk 3 with the power roller 11 is on the side far from the axis of the disk (upper side in FIG. 2) in order to increase the range width of the toroidal type continuously variable transmission, the bending moment is applied to the output side disk 3. And a large stress is generated on the traction surface. Therefore, the thickness T2 increases from the radius R, which is slightly on the inner diameter side than the height H of the portion Y where the stress generated on the traction surface is high, and the thickness increases toward the side farther from the axis of the disk (upper side in FIG. 2). Is thinner. Thus, by increasing the section modulus, the stress on the traction surface is relieved and the weight of the disk is reduced. If the radius R is reduced to the same value as the inner peripheral surface of the output side disk 3, the weight of the disk increases, so that the stress generated on the traction surface can be reduced to a minimum value.

  FIG. 3 is a half sectional view showing the output side disk 3 of the toroidal continuously variable transmission according to the third embodiment of the present invention, and FIG. 4 is a perspective view of the output side disk 3 shown in FIG. . In this embodiment, like the output side disk 3 shown in FIG. 1, the disk thickness T2 on the inner diameter side (lower side in FIG. 3) with a small pressing force is reduced, and the outer diameter side (FIG. In FIG. 3, the upper disk thickness T2 is increased to relieve the stress generated on the back surface. Further, a rib 77 having a thickness in the axial direction is formed on the back surface of the output side disk 3 as it goes to the inner diameter side (lower side in FIG. 3). Thereby, the stress generated on the traction surface due to the bending moment is relieved. Further, the base end portion of each rib 77 is connected to the outer peripheral surface of an annular portion 78 formed on the back surface of the output side disk 3. The annular portion 78 is formed in a cylindrical shape coaxially with the axis O of the output side disk 3. The radius R of the inner peripheral surface of the annular portion 78 is set similarly to the case of FIG. That is, the dimension is set to be slightly located on the inner diameter side of the radial dimension H of the portion Y where the stress generated on the traction surface is high.

In the present embodiment, the same effects as those of the second embodiment described above can be obtained, and further weight reduction can be achieved. That is, the disk thickness T2 becomes thicker as the part without the rib 77 goes to the outer diameter side farther from the axis O of the output side disk 3, and the part with the rib 77 becomes the outer diameter side farther from the axis O of the output side disk 3. The disk thickness T2 becomes thinner as the distance increases, so that the strength can be secured and the weight can be reduced.
The annular portion 78 may not be provided.

  FIG. 5 is a half cross-sectional view when the present invention is applied to the input side disk 2 of the toroidal-type continuously variable transmission. As shown in FIG. 5, the pressing force F1 generated at the contact point of the input side disk 2 with the power roller 11 is larger on the inner diameter side (lower side in FIG. 5) when the input torque is the same. The outer diameter side (upper side in FIG. 5) is smaller. For this reason, in the case of the input side disk 2, a large stress is generated on the back surface 72 in the vicinity of the contact point on the inner diameter side. Therefore, in the present embodiment, the stress generated on the back surface 72 near the contact point on the inner diameter side is relieved by changing the thickness T1 of the input side disk 2 in accordance with the pressing force F1 generated at the contact point. . Specifically, the disk thickness T1 on the inner diameter side where the pressing force F1 is large is increased, and the disk thickness T1 is decreased toward the outer diameter side (side far from the disk axis) where the pressing force F1 decreases. Thereby, weight reduction can be achieved, ensuring the intensity | strength of the input side disk 2. FIG. Here, the disc thickness T1 refers to the thickness in the axial direction of the disc. Further, the dimension setting relating to the disc thickness T1 is not applied to the cylindrical attachment portion formed at the base end portion of the input side disc 2 in order to attach the input side disc 2.

  In addition, by using the input side disk 2 and the output side disk 3 according to each of the above-described embodiments in combination, it is possible to further ensure the strength and reduce the weight.

  The present invention can be applied to a full toroidal continuously variable transmission as well as various half toroidal continuously variable transmissions such as a single cavity type and a double cavity type.

2 Input side disk 3 Output side disk 11 Power roller 72 Back surface 74 Back surface F1 Pressing force F2 Pressing force R Radius of notch H Height of high stress portion T1 Disc thickness T2 Disc thickness X Contact point Y Stress is high Part

Claims (3)

An input-side disk and an output-side disk that are concentrically and rotatably provided with the inner surfaces facing each other, and a power roller sandwiched between the input-side disk and the output-side disk. Toroidal-type continuously variable transmission with
The toroidal continuously variable transmission characterized in that the output side disk increases in thickness toward the outer diameter side. An input-side disk and an output-side disk that are concentrically and rotatably provided with the inner surfaces facing each other, and a power roller sandwiched between the input-side disk and the output-side disk. Toroidal-type continuously variable transmission with
The toroidal continuously variable transmission characterized in that the output side disk is thicker from the inner diameter side than the part where the stress generated on the traction surface is high, and is thinner toward the outer diameter side. . An input-side disk and an output-side disk that are concentrically and rotatably provided with the inner surfaces facing each other, and a power roller sandwiched between the input-side disk and the output-side disk. Toroidal-type continuously variable transmission with
The output side disk is thicker toward the outer diameter side, and a rib is provided on the back surface.
A toroidal continuously variable transmission characterized in that a plurality of the ribs are provided radially at intervals in the circumferential direction, and the height of each rib increases toward the inner diameter side.

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