JP4972931B2 - 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 toroidal continuously variable transmission used as a transmission for an automobile is configured as shown in FIGS. As shown in FIG. 4, the input shaft 1 is rotatably supported inside the casing 50, and two input side disks 2, 2 and two output side disks 3 are disposed on the outer periphery of the input shaft 1. 3 is 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 driven to rotate by a drive shaft 22 via a loading cam type pressing device 12 provided between an input side disk 2 and a cam plate (loading cam) 7 located on the left side in the drawing. It has become. 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 is provided between the inner side surfaces (concave surface; also referred to as a traction surface) 2a and 2a of the input side disks 2 and 2 and the inner side surfaces (concave surface; also referred to as a traction surface) 3a and 3a of the output disks 3 and 3. 11 (see FIG. 5) 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 (right surface in FIG. 4) of the input side disk 2 is abutted against a loading nut 9 screwed into a screw portion 1 e formed on the outer peripheral surface of the input shaft 1. 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.

  As shown in FIG. 5, which is a cross-sectional view taken along the line AA in FIG. The pair of yokes 23A and 23B is supported in the state. The pair of yokes 23A and 23B are formed in a rectangular shape by pressing or forging a metal such as steel. In order to support pivots 14 provided at both ends of the trunnion 15 to be described later in a swingable manner, circular support holes 18 are provided at the four corners of the yokes 23A and 23B, and the width direction of the yokes 23A and 23B. A circular locking hole 19 is provided at the center of the.

  The pair of yokes 23 </ b> A and 23 </ b> B are supported so as to be slightly displaceable by support posts 64 and 68 formed on portions of the inner surface of the casing 50 facing each other. These support posts 64 and 68 are provided so as to face the first cavity 221 and the second cavity 222, respectively, between the inner side surface 2a of the input side disk 2 and the inner side surface 3a of the output side disk 3. Yes.

  Therefore, the yokes 23 </ b> A and 23 </ b> B are supported by the support posts 64 and 68, and one end thereof faces the outer peripheral portion of the first cavity 221, and the other end faces the outer peripheral portion of the second cavity 222. doing.

  Since the first and second cavities 221 and 222 have the same structure, only the first cavity 221 will be described below.

  As shown in FIG. 5, inside the casing 50, the first cavity 221 is provided with 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. It has been. In addition, illustration of the input shaft 1 is abbreviate | omitted in FIG. Each trunnion 15, 15 is a pair of bent portions formed at both ends in the longitudinal direction (vertical direction in FIG. 5) of the support plate portion 16 that is the main body portion in a state of being bent toward the inner side surface of the support plate portion 16. Wall portions 20 and 20 are provided. 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.

  As described above, the pivot shafts 14 and 14 of the trunnions 15 and 15 are supported so as to be swingable with respect to the pair of yokes 23A and 23B and displaceable in the axial direction (vertical direction in FIG. 5). The trunnions 15 and 15 are restricted from moving in the horizontal direction by the yokes 23A and 23B. As described above, four circular support holes 18 are provided at the four corners of each of the yokes 23 </ b> A and 23 </ b> B. The pivot shafts 14 provided at both ends of the trunnion 15 are respectively provided in the support holes 18 with the radial needle bearings 30. It is supported so as to be able to swing through. Further, as described above, the 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. 5), and the inner peripheral surface of the locking hole 19 is spherical. Support posts 64 and 68 are internally fitted as concave surfaces. 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 the thrust ball bearings 24 is composed of a plurality of balls 26, 26, an annular retainer 27 for holding the balls 26, 26 in a freely rolling manner, and an annular outer ring 28. ing. 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 (shaft portions extending from the pivot shaft) 29 and 29 are provided at one end portions (lower end portions in FIG. 5) of the trunnions 15 and 15, respectively, and outer peripheral surfaces of intermediate portions of the drive rods 29 and 29 are provided. The drive pistons (hydraulic pistons) 33, 33 are fixedly provided. 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 drive shaft 22 is transmitted to the input side disks 2 and 2 and the input shaft 1 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 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 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, the yokes 23A and 23B, which support the pivot 14 of the trunnion 15 so as to be swingable and axially displaceable, swing themselves around the support posts 64 and 68, so that, for example, one trunnion A pair of trunnions facing each other in the same cavity so that the other trunnion 15 (for example, the left trunnion in FIG. 5) is displaced downward in accordance with the upward displacement of 15 (for example, the right trunnion in FIG. 5) It has the function to synchronize 15 movements like a seesaw and to displace these in the opposite directions. In relation to this, in Patent Document 1, for example, as shown in FIGS. 6 and 7, a projection 119 is formed on the yokes 23A and 23B, and the trunnion 15 is displaced up and down by the projection 119, so A structure that ensures synchronization of the tilting behavior of the trunnion 15 has been proposed.

Japanese Patent No. 3022112

  However, in the structure of Patent Document 1, when the trunnion 15 is displaced in the vertical direction at the time of shifting, the ends of the projections 119 of the yokes 23A and 23B come into contact with the trunnion 15, so that the trunnion 15 and the projection 119 A frictional force is generated on the two members, and there is a possibility that both the members 15 and 119 are worn. Further, such a frictional force becomes a resistance against the tilting movement of the trunnion 15, and there is a possibility that a smooth shifting operation may be hindered. Furthermore, since the protrusion 119 is formed integrally with the yokes 23A and 23B, the processing method of the yokes 23A and 23B is also restricted, and there is a problem that the manufacturing cost of the yokes 23A and 23B increases.

  The present invention has been made in view of the above circumstances, and while reducing the manufacturing cost of the yoke, the frictional force between the yoke and the trunnion is alleviated, and the smooth tilting movement of the trunnion accompanying the shifting operation is achieved. An object is to provide a toroidal-type continuously variable transmission that can be secured.

In order to achieve the object, the toroidal continuously variable transmission according to claim 1 is supported concentrically and rotatably in a state in which the inner surfaces of the toroidal continuously variable transmission face each other inside the casing. The input side disk and the output side disk, the plurality of power rollers sandwiched between the two disks, and the twisted position with respect to the central axis of the input side disk and the output side disk, and concentric with each other A plurality of trunnions that swing about a pair of pivots provided on the shaft and that rotatably support the power rollers, a drive device that displaces the trunnions in the axial direction of the pivots, and The pivot shaft includes a pair of yokes that support the pivot shafts so as to be swingable and axially displaceable, and swing by the displacement of the trunnion. In Idar type continuously variable transmission, between the trunnion and the yoke in the axial direction of said trunnion is axially insertion member of the pair contribute to oscillation of the yoke due to the displacement of the trunnions are provided, these The insertion members are engaged with each other by an uneven spherical surface in the axial direction of the trunnion .

  In the first aspect of the present invention, a pair of interposing members that are engaged with each other by the concavo-convex spherical surface are sandwiched between the trunnion and the yoke so that the force acting between the two at the time of shifting is always wide. I try to receive it on the surface. Therefore, the frictional force between the trunnion and the yoke can be relaxed, the wear of both can be reduced, and a smooth tilting movement of the trunnion accompanying the speed change operation can be ensured. That is, the reliability of the operation of the toroidal type continuously variable transmission is improved. Further, since no projection is formed on the yoke, the manufacturing cost of the yoke can be reduced.

  According to a second aspect of the present invention, in the invention described in the first aspect, the pair of insertion members are formed of an annular body that is attached to the outer periphery of the pivot shaft of the trunnion. The at least one annular body is set to have an inner diameter larger than the outer diameter of the pivot shaft of the trunnion, and a gap is formed between the pivot shaft and the pivot shaft so as to move in a direction substantially orthogonal to the axial direction of the pivot shaft. It is characterized by securing

  In the invention described in claim 2, since the movement of the annular body in a direction substantially orthogonal to the pivot axis of the trunnion is allowed, the spherically coupled annular bodies are aligned with each other when the yoke is inclined. Therefore, smooth swinging of the yoke due to axial displacement of the trunnion can be ensured. In other words, when the yoke is tilted at the time of shifting, it becomes impossible to maintain the parallel state between the central axis of the trunnion pivot and the central axis of the support hole of the yoke that supports the pivot, so the annular body is fixed to the trunnion or the yoke. If so, the center of the spherical surface is shifted, and the smooth swinging motion of the yoke is impaired. However, if at least one of the annular bodies is attached with a predetermined gap to the trunnion so that it can slide in a direction orthogonal to the pivot axis as in this configuration, the spherically coupled annular bodies are mutually connected when the yoke is tilted. It is possible to move so as to align, and it is possible to ensure smooth swinging of the yoke.

  According to a third aspect of the present invention, the toroidal-type continuously variable transmission according to the first or second aspect of the present invention is configured so that the concave and convex spherical surfaces of the interposing members that are engaged with each other are not relative to each other. It is characterized in that a friction reducing process is performed to relieve resistance to sliding.

  In the invention described in claim 3, since the concave and convex spherical surfaces of the interposing members that are engaged with each other are subjected to friction reduction processing, the trunnion tilting movement accompanying the shifting operation is performed more smoothly. Will be able to.

  According to the toroidal-type continuously variable transmission of the present invention, a pair of insertion members that are engaged with each other by an uneven spherical surface are sandwiched between a trunnion and a yoke, and the force acting between the two at the time of shifting is always wide. Therefore, the frictional force between the yoke and the trunnion can be reduced while reducing the manufacturing cost of the yoke, and the smooth tilting movement of the trunnion accompanying the shifting operation can be ensured.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The feature of the present invention lies in the force transmission structure between the yoke and the trunnion that accompanies the shift, and other configurations and operations are the same as the conventional configurations and operations described above. Only the characteristic part will be referred to, and the other parts will be simply described with the same reference numerals as those in FIGS.

  As shown in FIGS. 1 and 2, in this embodiment, as an insertion member that contributes to the swing of the yokes 23A and 23B due to the axial displacement of the trunnion 15 between the trunnion 15 and the yokes 23A and 23B. A pair of thin plate members 130 and 132 are provided. In other words, in this structure, the thin plate members 130 and 132 inserted between the trunnion 15 and the yokes 23A and 23B cause the yokes 23A and 23B to swing due to the axial movement of the trunnion 15 of the driving device 32. (This swinging is caused by the thin plate members 130 and 132 pushing up one end side of the yokes 23A and 23B as the trunnion 15 is moved in the axial direction by the drive device 32) and accompanying the swinging of the yokes 23A and 23B. An axial movement of the trunnion 15 is caused (this axial movement is caused by the thin plate members 130 and 132 pushing the trunnion 15 down). Accordingly, the trunnion 15 is displaced up and down to synchronize the tilting behavior of the trunnion 15 at the time of shifting (the other trunnion 15 is displaced downward as the one trunnion 15 is displaced upward). The function of synchronizing the movements of the pair of trunnions 15 facing each other in the cavity like a seesaw and displacing them in the opposite directions can be ensured.

  In the present embodiment, the thin plate members 130 and 132 are formed of an annular body that is attached to the outer periphery of the pivot 14 of the trunnion 15. Then, at least one annular body, in this embodiment, one thin plate member 130 located on the side of the yokes 23A and 23B has an inner diameter larger than the outer diameter of the pivot 14 of the trunnion 15, as clearly shown in FIG. A clearance s is secured between the pivot 14 and the pivot 14 so as to be movable in a direction substantially orthogonal to the axial direction of the pivot 14 (direction indicated by an arrow in FIG. 2).

  In the present embodiment, the pair of thin plate members 130 and 132 are engaged with each other by an uneven spherical surface. Specifically, as shown in FIG. 3, a concave spherical surface 130a is provided on the thin plate member 130 located on the yokes 23A and 23B side, while a convex spherical surface 132a is provided on the thin plate member 132 located on the trunnion 15 side. These spherical surfaces 130a and 132a are engaged with each other.

  Furthermore, in the present embodiment, the concave and convex spherical surfaces of the thin plate members 130 and 132 that are engaged with each other are subjected to a friction reducing process for relaxing the resistance against relative sliding. Specifically, in the present embodiment, a coating for reducing the coefficient of friction is applied to the sliding surfaces of the thin plate members 130 and 132, and more specifically, one of the spherical surfaces 130a and 132a that are engaged with each other. A layer 140 made of polytetrafluoroethylene (PTFE) is formed. Any friction reducing process may be used as long as it reduces the resistance against relative sliding of the concave and convex spherical surfaces 130a and 132a of the thin plate members 130 and 132.

  As described above, in the present embodiment, the pair of thin plate members 130 and 132 that are engaged with each other by the concave and convex spherical surfaces 130a and 132a are sandwiched between the trunnion 15 and the yokes 23A and 23B. 15; The force acting between 23A and 23B is always received on a wide surface. Therefore, the frictional force between the trunnion 15 and the yokes 23A and 23B can be relaxed, wear of both 15; 23A and 23B can be reduced, and a smooth tilting motion of the trunnion 15 accompanying the speed change operation can be secured. That is, the reliability of the operation of the toroidal type continuously variable transmission is improved. Further, since no projection is formed on the yokes 23A and 23B, the manufacturing cost of the yokes 23A and 23B can be reduced.

  In the present embodiment, since the thin plate member 130 is allowed to move in a direction substantially orthogonal to the pivot 14 of the trunnion 15, when the yokes 23A and 23B are inclined, the spherically coupled thin plate members 130 and 132 are adjusted to each other. Therefore, the yokes 23A and 23B can be smoothly swung by the axial displacement of the trunnion 15. That is, when the yokes 23A and 23B are inclined at the time of shifting, it becomes impossible to maintain a parallel state between the central axis of the pivot 14 of the trunnion 15 and the central axis of the support hole 18 of the yokes 23A and 23B supporting the pivot 14. When the members 130 and 132 are fixed to the trunnion 15 or the yokes 23A and 23B, the centers of the spherical surfaces 130a and 132a are shifted, and the smooth swinging motion of the yokes 23A and 23B is impaired. However, when at least one (130) of the thin plate members 130, 132 is attached to the trunnion 15 with a predetermined gap s so that the thin plate members 130, 132 can slide in a direction perpendicular to the pivot shaft 14 as in this configuration, the yokes 23A, 23B are attached. When tilted, the spherically coupled thin plate members 130 and 132 can move so as to align with each other, and smooth swinging of the yokes 23A and 23B can be ensured.

  Further, in this embodiment, since the concave and convex spherical surfaces 130a and 132a of the thin plate members 130 and 132 that are engaged with each other are subjected to the friction reducing process, the tilting movement of the trunnion 15 accompanying the shifting operation is performed more smoothly. Will be able to.

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

It is principal part sectional drawing of the toroidal continuously variable transmission which concerns on embodiment of this invention. It is a principal part expanded sectional view of the toroidal continuously variable transmission of FIG. It is an expanded sectional view of a thin plate member. It is sectional drawing which shows an example of the specific structure of the toroidal type continuously variable transmission conventionally known. It is sectional drawing which follows the AA line of FIG. It is principal part sectional drawing which shows the prior art example of the force transmission structure between the yoke and trunnion accompanying transmission. It is a principal part expanded sectional view of the toroidal continuously variable transmission of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input shaft 2 Input side disk 3 Output side disk 11 Power roller 14 Pivot 15 Trunnion 23A, 23B Yoke 32 Drive apparatus 130, 132 Thin plate member (insertion member)
130a, 132a spherical surface 140 layers s gap

Claims (3)

A casing, an input-side disk and an output-side disk that are supported concentrically and rotatably with the inner surfaces facing each other inside the casing, and a plurality of sandwiched between the two disks The power roller swings about a pair of pivots that are concentrically arranged with respect to the center axis of the input side disk and the output side disk, and each power roller is rotatable. A plurality of trunnions that are supported on the shaft, a drive device that displaces each trunnion in the axial direction of the pivot, and supports each pivot of each trunnion so as to be swingable and axially displaceable. In a toroidal continuously variable transmission comprising a pair of yokes that swing by displacement,
Between the trunnion and the yoke in the axial direction of the trunnion, a pair of insertion members that contribute to the swinging of the yoke due to the axial displacement of the trunnion are provided, and these insertion members are connected to the trunnion. A toroidal-type continuously variable transmission which is engaged with each other by an uneven spherical surface in the axial direction .   The pair of insertion members is composed of an annular body mounted on an outer periphery of the pivot shaft of the trunnion, and at least one annular body has an inner diameter set larger than an outer diameter of the pivot shaft of the trunnion, and the pivot shaft The toroidal continuously variable transmission according to claim 1, wherein a clearance is secured between the pivot shaft and the pivot shaft so as to move in a direction substantially perpendicular to the axial direction.   The concave and convex spherical surfaces of the interposing members that are engaged with each other are subjected to a friction reducing process for relaxing resistance to relative sliding. The toroidal type continuously variable transmission described.

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