JP5077834B2 - 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 type toroidal continuously variable transmission used as a transmission for an automobile is configured as shown in FIGS. As shown in FIG. 8, 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, the power roller 11 (see FIG. 9) is rotatable between the inner side surfaces (concave surfaces) 2a, 2a of the input side discs 2, 2 and the inner side surfaces (concave surfaces) 3a, 3a of the output side discs 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. 8, 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 (right surface in FIG. 8) 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. 9 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 9, 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 FIG. 9, the input shaft 1 is not shown. 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. 9) 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. In addition, each power roller 11 is rotatably supported around the tip end portion (second shaft 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. 9) 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. Further, a circular locking hole 19 is provided in the central portion of the yokes 23A and 23B in the width direction (the left-right direction in FIG. 8). 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.

  Further, driving rods (trunnion shafts) 29 and 29 are provided at one end portions (lower end portions in FIG. 9) of the trunnions 15 and 15, respectively, and driving pistons ( 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. It 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. 9 is displaced downward in the figure, and the power roller 11 on the right side of FIG. 9 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.

  In such a toroidal-type continuously variable transmission, as described above, the power rollers 11, 11 are slightly swung around the base end portions 23a, 23a of the displacement shafts 23, 23, so that the power rollers 11, 11 is slightly moved in the axial direction of the input shaft 1 (disks 2 and 3) so as to cope with the change in the elastic deformation amount of each constituent member. A configuration has been proposed in which each component can be moved in accordance with a change in the amount of elastic deformation (see, for example, Patent Document 1).

For example, as shown in FIG. 10, a support beam portion 16 a is provided in place of the support plate portion 16 of the trunnion 15. An inner side surface of the support beam portion 16a facing the outer ring 28 is a cylindrical convex surface 16b. The direction of the central axis A (illustrated by the one-dot chain line) of the cylindrical portion of the cylindrical convex surface 16b is parallel to the axial direction of the pivots 14 and 14 (the direction of the central axis B (illustrated by the one-dot chain line)).
Further, the central axis A of the cylindrical convex surface 16b is on the radially outer side of the input side disk 2 and the output side disk 3 with respect to the central axis B of the pivots 14 and 14. That is, the central axis of the cylindrical convex surface 16b is eccentric to the side away from the power rollers 11, 11 from the central axis of the pivots 14, 14 along the direction of the rotation center axis of the power rollers 11, 11 at the neutral position. It has become.

A cylindrical concave surface having an inner diameter substantially the same as the outer diameter of the cylindrical convex surface 16b is provided on the outer surface side of the outer ring 28 facing the support beam portion 16a, and the inner circumferential surface of the cylindrical concave surface is a cylindrical convex surface. The outer ring 28 can be swung to the left and right together with the power roller 11 with the central axis of the cylindrical convex surface 16b as a rotation center in a state of being in contact with the outer peripheral surface of 16b.
As a result, the power rollers 11 and 11 can be moved slightly in the axial direction of the input shaft 1 (rotation center axis of the disks 2 and 3) to cope with changes in the amount of elastic deformation of each constituent member.

In FIG. 10, guide surfaces 20 a that contact the outer peripheral surface of the outer ring 28 are formed on the inner surfaces of the pair of bent wall portions 20, 20 of the trunnion 15 that are opposed to each other. When the traction force is applied, the outer peripheral surface of the outer ring 28 comes into contact with one of the guide surfaces 20a, and the traction force is transmitted from the power roller 11 to the trunnion 15.
The power rollers 11, 11 are rotatably supported on a support shaft 23c corresponding to the tip 23b of the displacement shaft 23 via a radial needle bearing. The support shaft 23 c is formed integrally with the outer ring 28. The power rollers 11, 11 are secured to the support shaft 23c by a washer 11b and a retaining ring 11c.

  In addition, a wire pulley is provided on the lower side of the radial needle bearing 30 of the pivot 14 on the side where the drive rod 29 of the trunnion 15 is provided, and wires for synchronizing the tilt angles of the trunnions 15 and 15 are spanned as in the prior art. 29a is provided. In this example, an oil supply pipe 29b for supplying lubricating oil from the drive rod 29 side to the power rollers 11 and 11 side is provided on the outer surface side opposite to the power rollers 11 and 11 of the trunnion 15. .

  By the way, the traction drive type toroidal continuously variable transmission transmits power using a special oil (traction oil) that transitions into a glass state under a high pressure. Therefore, in the power transmission state, it is necessary to apply a pressing force proportional to the torque to be transmitted to the contact point between the disks 2 and 3 and the power rollers 11 and 11. By applying a pressing force, the power rollers 11 and 11 sandwiched between the disks 2 and 3 and the trunnions 15 and 15 that support the power rollers 11 and 11 receive a large force that escapes outward. In order to support this force, the above-described yokes 23A and 23B are arranged above and below the trunnions 15 and 15, and the pivots 14 and 14 of the trunnion 15 are supported.

  The yokes 23A and 23B restrict the movement of the trunnions 15 and 15 to the outside. In the case where the yokes 23A and 23B are not provided, the power rollers 11 and 11 may be displaced from the correct positions to cause a decrease in efficiency and a decrease in life. The yokes 23A and 23B swing around the spherical posts 64 and 68, pins and protrusions described above, but nothing restricts the gap between the trunnions 15 and 15 and the yokes 23A and 23B. There is a high possibility that the yokes 23A and 23B come into contact with each other.

In this state, when the trunnions 15 and 15 perform a rotational motion (tilting motion) around the tilt axis (the central axis B of the pivot shafts 14 and 14), the shoulder portions (bent wall portions 20 and 20) of the trunnions 15 and 15 are obtained. ) And the yokes 23 </ b> A and 23 </ b> B rub against each other to increase the frictional resistance. When the frictional resistance is increased, the tilting motion is hindered and the operation may be unstable.
In order to cope with this problem, it has been proposed to provide protrusions at the portions of the yokes 23A and 23B that contact the trunnions 15 and 15 to reduce the contact area and reduce friction during tilting (see, for example, Patent Document 2). ).

  Further, when the trunnions 15 and 15 and the yokes 23A and 23B come into contact with each other, the contact portions of the trunnions 15 and 15 with the yokes 23A and 23B are worn. Therefore, it has been proposed to prevent wear by quenching the portions of the trunnions 15 and 15 that come into contact with the yokes 23A and 23B to increase the surface hardness (see, for example, Patent Document 3).

Further, a configuration is adopted in which a plate is held between a radial needle bearing 30 provided on the pivot 14 of the trunnions 15 and 15 and serving as a tilt bearing and a shoulder portion of the trunnions 15 and 15, and this plate and the yoke 23A, It has been proposed to prevent wear of the trunnions 15 and 15 by bringing them into contact with 23B (see, for example, Patent Document 4).
Further, at the contact portion between the trunnions 15 and 15 and the yokes 23A and 23B, an arc-shaped groove centering on the central axis of the pivot shafts 14 and 14 is provided on either side, and a plurality of balls are arranged in the grooves. It has been proposed to reduce both friction and wear by rolling the trunnions 15 and 15 and the yokes 23A and 23B (see, for example, Patent Document 5).

JP 2008-25821 A JP 7-174201 A JP 2004-286053 A JP 2005-121045 A JP 2001-323882 A

In the invention of Patent Document 2, friction can be reduced by providing a projection that contacts the trunnion on the yoke, but wear on the trunnion due to contact with the yoke cannot be prevented. Further, providing the projection on the yoke causes an increase in cost.
Moreover, in invention of patent document 3, although it can prevent abrasion of trunnion by hardening, it cannot necessarily reduce friction. In addition, the trunnion needs to be finished, and an increase in cost cannot be avoided.

Moreover, in the invention of Patent Document 4, although the processing cost of the trunnion and the yoke does not increase, the friction cannot always be reduced.
In the invention of Patent Document 5, both friction and wear can be reduced. For example, an arc-shaped groove is formed in the trunnion, and the groove becomes a ball transfer surface, so that surface processing of the groove is required. , Processing costs increase. In addition, there is a problem that workability is poor because it is necessary to prevent the ball from falling or being displaced during assembly.

  The present invention has been made in view of the above circumstances, and is a toroidal type capable of reducing friction and wear in the contact between the trunnion and the yoke, facilitating the processing of the trunnion, and preventing an increase in processing cost. An object is to provide a continuously variable transmission.

In order to achieve the object, the toroidal continuously variable transmission according to claim 1 includes an input side disk and an output side that are concentrically and rotatably supported with their inner side surfaces facing each other. A disc, a plurality of power rollers sandwiched between the two discs, and a pair of pivots provided concentrically with each other at a twisted position with respect to a central axis of the input side disc and the output side disc A plurality of trunnions that tilt to the center and rotatably support the power rollers via thrust bearings, a drive device that displaces the trunnions in the axial direction of the pivots, and the pair of pivots of the trunnions Each of the thrust bearings includes a pair of yokes that are swingable and axially displaceable, and that are swung by the displacement of the trunnion. An inner ring formed by the power roller, an outer ring, and a rolling element that rolls between the inner ring and the outer ring, the trunnion has a cylindrical convex surface formed on a surface facing the power roller side, A central axis of the cylindrical convex surface is disposed at a position parallel to the central axis of the pivot axis and away from the central axes of the input side disk and the output side disk from the central axis of the pivot axis, and the outer ring has the trunnion A toroidal-type continuously variable transmission that includes a cylindrical concave surface that abuts on the cylindrical convex surface of the trunnion and that is rotatable about the central axis of the cylindrical convex surface of the trunnion.
The upper and lower end surfaces of the trunnion facing the yoke are each provided with a hole at a position intersecting the central axis of the cylindrical convex surface, and a contact member that contacts the yoke is attached to the hole. Is a hole for processing reference when the cylindrical convex surface is formed .

  In the first aspect of the invention, the contact member attached to the hole formed in the end surface of the trunnion can contact the yoke, and the trunnion can be prevented from contacting the yoke, so that the trunnion can be prevented from being worn. . Further, the contact member can reduce the contact surface with the yoke depending on the shape thereof, and can reduce the frictional force generated between the trunnion and the yoke.

  Moreover, since the said hole becomes the center of the cylindrical convex surface of a trunnion, when forming a cylindrical convex surface in a trunnion, a process can be made easy by making the said upper and lower said hole into a process reference | standard. . Further, the processing of the cylindrical convex surface can be performed at a low cost with a lathe or the like, and the workability is improved by the presence of the hole serving as the processing reference. The hole can also be used as a reference in inspection after processing (inspection of accuracy and the like of the cylindrical convex surface).

In other words, than the holes for providing the contact member shall be the holes for working reference, and holes for fixing the contact member, it is not necessary to the hole for working reference provided two, reducing the processing cost Can be achieved. The hole is used as a processing reference when the trunnion is processed, and the contact member is attached after at least the cylindrical convex surface has been processed .
In addition, these holes are formed on the end face where the trunnion pivot is provided, so stress may be concentrated, reducing the number of holes, that is, making contact with the machining reference holes as described above. The rigidity of the trunnion can be increased by sharing these without providing two holes for attaching the members.

According to a second aspect of the present invention, in the toroidal continuously variable transmission according to the first aspect of the present invention, the hole has a different diameter between a shallow position and a deep position, and a portion having a small diameter on the deep side is used for a machining reference. It is a hole .

  According to the toroidal type continuously variable transmission of the present invention, it is possible to prevent the influence of trunnion friction that may slide with respect to the yoke, to prevent the trunnion from being worn, and to reduce the processing cost of the trunnion. Reduction can be achieved.

It is principal part sectional drawing which shows the toroidal type continuously variable transmission of embodiment of this invention. It is a perspective view which shows the trunnion provided with the power roller of the said toroidal type continuously variable transmission. It is a front view which shows the trunnion provided with the said power roller. It is sectional drawing which follows the BB line of FIG. It is a perspective view which shows the said trunnion. It is a front view which shows the said trunnion. It is sectional drawing along CC line of FIG. 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 side view which shows another example of the trunnion provided with the power roller of the conventional half toroidal type continuously variable transmission.

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The feature of the toroidal-type continuously variable transmission of this embodiment is the structure of the portion that contacts the yoke of the trunnion, and other configurations and operations are the same as the conventional configurations and operations described above. Refers only to the characteristic part of the first embodiment, and other parts are simply described with the same reference numerals as in FIGS.

  FIG. 1 is a cross-sectional view of a principal part showing a toroidal type continuously variable transmission according to an embodiment of the present invention, FIG. 2 is a perspective view showing a trunnion provided with a power roller of the toroidal type continuously variable transmission, and FIG. FIG. 4 is a cross-sectional view taken along line BB in FIG. 3, FIG. 5 is a perspective view showing the trunnion, FIG. 6 is a front view showing the trunnion, and FIG. It is sectional drawing along CC line.

  In the example shown in FIGS. 8 and 9, the yoke 23A and the yoke 23B have a spherical post 64, 68 inserted into a locking hole 19 formed in the yoke 23A, 23B, and the spherical post 64, 68 serves as a casing. However, in this example, as shown in FIG. 1, a protrusion 65 provided at the center of the outer surface side of the yokes 23A and 23B (the side surface opposite to the power roller 11). , 66 are made swingable. In addition, the protrusions 65 and 66 are in contact with a member fixed to the casing 50, for example.

  Further, in the example shown in FIG. 10, a part of the path of the oil path for supplying the lubricating oil from the drive rod 29 side to the various bearings of the power roller 11 is formed outside the trunnion 15 by the oil supply pipe 29b. As shown in FIGS. 1 and 4, in this example, all the oil passages of the lubricating oil from the drive rod 29 side to the power roller 11 side are formed as oil holes 15 a inside the trunnion 15.

  As shown in FIGS. 1 to 7, in the trunnion 15 provided with the power roller 11 in the toroidal-type continuously variable transmission of this example, as in the example shown in FIG. 10, the portion that supports the power roller 11 of the trunnion 15. Is a support beam 16a instead of the support plate 16, and the surface facing the power roller 11 is a cylindrical convex surface 16b. The power roller 11 rotates (tilts) around the axis of the pivot 14 integrally with the trunnion 15, and rotates around the central axis of the cylindrical convex surface 16 b so that the axial direction of the input shaft 1 (disc It can be displaced in the direction of a few rotation center axes).

  The distance from the tip of the central axis of the power roller 11 to the axis of the pivot 14 is shorter than the distance from the tip to the central axis of the cylindrical convex surface 16b. That is, the radius of rotation about the axis of the pivot 14 of the power roller 11 is narrower than the radius of rotation about the axis of the cylindrical convex surface of the power roller 11.

  Further, the power roller 11 is secured to a support shaft 23c integrated with the outer ring 28 by a retaining ring 11c or the like so that the thrust ball bearing 24 including the outer ring 28 is prevented from being detached from the power roller 11, and the outer ring 28 is A cylindrical concave surface 28a is formed on the outer surface of the trunnion 15 facing the support beam portion 16a, and the cylindrical concave surface 28a is in contact with the cylindrical convex surface 16b of the trunnion 15 in a freely rotatable manner. The cylindrical radii of the cylindrical convex surface 16b and the cylindrical concave surface 28a are substantially equal. Further, the outer ring 28 is pressed by the separation preventing bracket 16c so as not to be separated from the support beam portion 16a. The separation preventing bracket 16c is arranged in a state of straddling the back surface side of the support beam portion 16a, and both end portions are provided on the left and right side portions of the back surface of the outer ring 28 in a state of protruding from the support beam portion 16a to the left and right. It is fixed. Further, the separation preventing bracket 16c does not hinder the rotation within the necessary range around the cylindrical convex surface 16b of the power roller 11.

  Here, when the power roller 11 is rotated around the axis of the cylindrical convex surface 16b, the power roller 11 also moves in the axial direction of the input shaft 1 as described above. It becomes possible to cope with the displacement of the member. However, when the power roller 11 is rotated around the cylindrical convex surface 16b in an operation similar to the case where the power roller 11 is tilted around the pivot axis 14, there is a possibility that the transmission ratio may be affected, but as described above, around the cylindrical convex surface 16b. Since the rotation radius of the power roller 11 is larger than the rotation radius of the power roller 11 around the pivot axis 14, the influence on the transmission ratio is extremely small, and it is a level that does not affect the actual transmission or can be easily corrected. In particular, there is no problem with the gear ratio.

  Further, the trunnion 15 having such a cylindrical convex surface 16b and rotating the power roller 11 as described above around the cylindrical convex surface 16b to displace it in the direction of the input shaft 1 causes the power roller 11 to move toward the input shaft. In order to displace in one direction, the manufacturing cost can be reduced as compared with the case where the power roller 11 is swung by the displacement shaft 23 or the case where the power roller 11 is moved to the left and right with respect to the inner surface of the trunnion 15.

  Further, the outer ring 28 is rotated integrally with the power roller 11 in a state where the cylindrical convex surface 16b of the trunnion 15 and the cylindrical concave surface 28a of the outer ring 28 are in contact with each other, and the power roller 11 is moved in the direction of the input shaft 1. In the configuration, since the swing resistance when displacing the power roller 11 in the direction of the input shaft 1 can be reduced as compared with the above-described one using the displacement shaft 23, the pressing force of the pressing device 12 is efficiently traction contacted. Can communicate to the point. As a result, the traction coefficient can be set large. That is, it is possible to reduce the margin between the limit traction coefficient and the motion traction coefficient that are conventionally required for the trunnion. As a result, the efficiency of the transmission can be improved.

In this example, both end surfaces 15b and 15b where the pivots 14 and 14 of the trunnion 15 are formed, that is, both end surfaces of the support beam portion 16a, are located at positions that are the outer surfaces of the base end portions of the bent wall portions 20 and 20. A hole 101 is formed at a position that overlaps (intersects with) the center line of the cylindrical convex surface 16b of the support beam portion 16a.
The hole 101 is formed in a circular cross section, that is, in a columnar shape, and is formed so that the center of the column coincides with the center of the cylinder of the cylindrical convex surface 16b.

In addition, the hole 101 has a different diameter between a shallow position and a deep position, and the shallow position is formed to have a diameter corresponding to a diameter of a contact member 102 to be press-fitted into the hole 101, which will be described later. A diameter narrower than the diameter is adopted for the deep position. The diameter at the deep position is half or less than the outer diameter of the contact member 102, and the contact member 102 cannot enter. Further, the deep position and the shallow position of the hole 101 are arranged coaxially, and this central axis coincides with the central axis of the cylindrical convex surface 16b.
In other words, the center of the hole 101 is provided at the center of the both end faces 15b, 15b of the trunnion 15 of the cylindrical convex surface 16b. A spherical contact member 102 is attached to the hole 101. Note that the hole 101 does not have to have a different diameter depending on the depth as described above, and the hole 101 may have a cylindrical shape whose diameter does not vary with the depth.

The contact member 102 is attached by being press-fitted into the hole 101 of the trunnion 15.
Further, end surfaces 15b and 15b provided with the pivot 14 of the trunnion 15 are end surfaces facing the yokes 23A and 23B, respectively. That is, in FIG. 1, the upper end surface 15b of the trunnion 15 faces the yoke 23A, and the lower end surface 15b of the trunnion 15 faces the yoke 23B.

The contact member 102 protrudes from the end faces 15b, 15b of the trunnion 15 toward the yokes 23A, 23B. The center of the spherical contact member 102 is arranged so as to coincide with the center line of the hole 101 and coincide with the center line of the cylindrical convex surface 16b.
The trunnion 15 and the yokes 23A and 23B are substantially in contact with each other at a position that is a tip of a portion protruding from the end surfaces 15b and 15b of the trunnion 15 of the contact member 102.

Thereby, the contact member 102 press-fitted into the hole 101 is interposed between the trunnion 15 and the yokes 23A and 23B, and the trunnion 15 and the yokes 23A and 23B are not in contact with each other.
In addition, the upper and lower contact members 102 are basically almost always in contact with the yokes 23A and 23B, that is, the contact member 102 and the yokes 23A and 23B are maintained in substantially contact with each other with a slight clearance. It is like that.

The outer surface of the support beam portion 16 a of the trunnion 15 opposite to the cylindrical convex surface 16 b is a cylindrical convex surface 16 d centering on the central axis of the pivot 14.
That is, as shown in FIG. 7, the support beam portion 16 a of the trunnion 15 has a cylindrical convex surface 16 b centered on the central axis A on the power roller 11 side, and the opposite side centered on the central axis B of the pivot 14. It is a cylindrical convex surface 16d.

And at the time of a process, the trunnion 15 is set to a lathe using the hole 101 of the end surface of the trunnion 15, for example. At this time, a portion having a small diameter on the deep side of the hole 101 may be used.
Then, for example, the support beam portion 16a is processed into a columnar shape centered on the central axis a. Next, the trunnion 15 is set on a lathe using the pivots 14 and 14 on the peripheral surface portion of the support beam portion 16a opposite to the power roller 11, and the support beam portion 16a processed as described above A portion protruding from a circle having a predetermined radius from the central axis B of the pivot 14 is processed into a cylindrical shape to form a cylindrical convex surface 16d.
The portion of the support beam portion 16a opposite to the power roller 11, that is, the back surface portion of the trunnion 15 is formed as a cylindrical convex surface 16d with the center axis of the pivot shaft 14 as the center. Even if the trunnion 15 rotates, there is no member protruding from the back surface of the trunnion 15, and the trunnion 15 that rotates about the pivot 14 can be arranged in a compact manner.

Then, by pressing the contact member 102 into the hole 101, the contact member 102 is attached to the trunnion 15 using the hole 101, that is, the processing reference hole 101.
In addition, it is good also as a structure which forms a female screw in the inner periphery of the hole 101, forms a male screw in the outer periphery of the contact member 102, and is screwed. For example, the contact member 102 may be attached to the hole 101 by welding. However, it is preferable to press-fit the contact member 102 into the hole 101 in consideration of processing cost and ease of work.
Thus, since the support beam part 16a corresponding to the conventional support plate part 16 of the trunnion 15 can be processed, the manufacturing cost of the trunnion 15 can be reduced.
For example, a standard product sphere can be used as the contact member 102 and can be obtained at a low cost. The contact member 102 preferably has a hardness, particularly a surface hardness, higher than that of the trunnion 15. That is, the contact member 102 is preferably formed from a member harder than the trunnion 15. Note that the contact member 102 and the trunnion 15 may be made of the same material. In this case, the contact member 102 is preferably hardened by heat treatment such as quenching.

  Since the contact member 102 contacts the yokes 23A and 23B and the trunnion 15 does not contact the yokes 23A and 23B, wear of the trunnion 15 can be prevented. Further, in order to prevent the trunnion 15 from being worn, it is not necessary to quench the portion of the trunnion 15 that comes into contact with the yoke 23A, and the processing cost of the trunnion 15 can be reduced.

  Further, since the sphere as the contact member 102 is used, the contact area between the contact member 102 and the yokes 23A and 23B becomes almost a point, and the friction acting between them can be reduced. At this time, since it is not necessary to form projections or the like on the trunnions 15 and 15 or the yokes 23A and 23B, the processing cost can be reduced. The contact member 102 does not need to be spherical. For example, the contact member 102 has a cylindrical shape, a shape in which a portion in contact with the yokes 23A and 23B is hemispherical, or a similar shape, and is provided on the end surface 15b of the trunnion 15. It may have a bowl-like structure that contacts over a wide area.

  Further, an insertion portion inserted (press-fitted) into the hole 101 of the trunnion 15 so as to shift the contact position with the yokes 23A and 23B from the center of the cylindrical convex surface 16b, and the end surface 15b of the trunnion 15 from the insertion portion. Further, it may be composed of an extending portion extending in any direction and a contact portion that protrudes from, for example, the tip portion of the extending portion to the yokes 23A and 23B and contacts the yokes 23A and 23B. That is, the contact position between the yokes 23A and 23B and the contact member 102 need not be on the center line of the cylindrical convex surface 16b.

However, the portions of the contact member 102 that come into contact with the yokes 23A and 23B need to have a small area and a high hardness so as not to wear (for example, higher than the hardness of the trunnion 15).
Further, when the contact member 102 is held in a state of being substantially in contact with the yokes 23A and 23B, the yoke is more effective than the case where there is a gap between the trunnions 15 and 15 and the yokes 23A and 23B without the contact member 102. A plurality of trunnions 15 supported by 23A and 23B, for example, four trunnions 15 move up and down accurately in synchronization with the swing of the yokes 23A and 23B, and the trunnions 15 are moved along the yokes 23A and 23B. It becomes possible to synchronize more reliably by using.

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

1 Input shaft (rotation center axis)
2 Input side disk 2a Inner side surface 3 Output side disk 3a Inner side surface 11 Power roller (inner ring)
14 pivot 15 trunnion 16a support beam 16b cylindrical convex surface 23A yoke 23B yoke 24 thrust ball bearing (thrust bearing)
26 Rolling element 28 Outer ring 28a Cylindrical concave surface 32 Drive device 101 Hole 102 Contact member

Claims (2)

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 tilting about a pair of pivots concentrically provided with respect to the center axis of the output-side disk, and rotatably supporting each power roller via a thrust bearing A plurality of trunnions, a driving device for displacing the trunnions in the axial direction of the pivot, and the pair of pivots of the trunnion are supported so as to be swingable and displaceable in the axial direction. The thrust bearing includes an inner ring formed by the power roller, an outer ring, and the inner ring and the outer ring. The trunnion is formed with a cylindrical convex surface on the surface facing the power roller, and the central axis of the cylindrical convex surface is parallel to the central axis of the pivot and the trunnion It is disposed at a position away from the central axis of the input side disk and the output side disk from the central axis of the pivot axis, the outer ring is provided with a cylindrical concave surface that abuts the cylindrical convex surface of the trunnion, and the power roller In the toroidal-type continuously variable transmission that is rotatable around the central axis of the cylindrical convex surface of the trunnion together with the outer ring,
The upper and lower end surfaces of the trunnion facing the yoke are each provided with a hole at a position intersecting the central axis of the cylindrical convex surface, and a contact member that contacts the yoke is attached to the hole. Is a toroidal-type continuously variable transmission which forms a hole for processing reference when the cylindrical convex surface is formed . 2. The toroidal continuously variable transmission according to claim 1, wherein a diameter of the hole is different between a shallow position and a deep position, and a portion having a small diameter on the deep side serves as a hole for processing reference .

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