JP4941712B2 - 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. 7, 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 on a partition wall (intermediate wall) 13 formed by coupling two members via an angular ball bearing 107 and is supported in the casing 50 via the partition wall 13. Thus, while being able to rotate around the axis O of the input shaft 1, displacement in the direction of the axis O 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. 8) is rotatably held.

  A step 2b is provided on the inner peripheral surface 2c of the input side disk 2 located on the right side in FIG. 7, 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. 7) of the input side disk 2 is abutted against a loading nut 9 screwed into a screw portion 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. 8 which is a cross-sectional view taken along the line AA in FIG. 7, both the disks 3 and 3 are sandwiched from both sides inside the casing 50 and laterally to the output side disks 3 and 3. 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 23A and 23B is supported by support posts 64 and 68 formed on the inner surface of the casing 50 so as to be able to swing around the support posts 64 and 68 as fulcrums. 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. 8, inside the casing 50, the first cavity 221 includes a pair of trunnions that swing about a pair of pivots (tilting shafts) 14 and 14 that are twisted with respect to the input shaft 1. 15 and 15 are provided. In addition, illustration of the input shaft 1 is abbreviate | omitted in FIG. Each trunnion 15, 15 is a pair of bent portions formed in a state of being bent toward the inner side surface of the support plate portion 16 at both ends in the longitudinal direction (vertical direction in FIG. 8) of the support plate portion 16 as the main body portion. 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.

  Further, as described above, the pivot shafts 14 of the trunnions 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. 8). 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 23A and 23B, and the pivot shafts 14 provided at both ends of the trunnion 15 are respectively provided in the support holes 18 with radial needle bearings ( A tilting bearing 30 is supported so as to be swingable (tiltable). Further, as described above, the circular locking hole 19 is provided in the central part of the yokes 23A and 23B in the width direction (left and right direction in FIG. 8), and the inner peripheral surface of the locking hole 19 is cylindrical. Support posts 64 and 68 are internally fitted as 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 the both disks 2, 2, 3, 3 (up and down in FIG. 8). (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 respectively provided at one end portions (lower end portions in FIG. 8) of the trunnions 15 and 15, and outer peripheral surfaces of intermediate portions of the drive rods 29 and 29, respectively. 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 (offset) in opposite directions. For example, the power roller 11 on the left side in FIG. 8 is displaced to the lower side in the figure, and the power roller 11 on the right side in the figure is displaced to the upper side in the figure. As a result, the peripheral surfaces 11a and 11a of the power rollers 11 and 11 act on contact portions of the input side disks 2 and 2 and the inner side surfaces 2a, 2a, 3a and 3a of the output side disks 3 and 3, respectively. The direction of the tangential force changes. As the force changes, the trunnions 15 and 15 swing (tilt) in opposite directions around the pivots 14 and 14 pivotally supported by the yokes 23A and 23B.

  As a result, the contact position between the peripheral surfaces 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, in the toroidal type continuously variable transmission having the above-described configuration, the yokes 23A and 23B for supporting the pivot shaft 14 of the trunnion 15 so as to be swingable and displaceable in the axial direction are conventionally known in various structures. In general, however, by itself swinging around the spherical posts 64 and 68, for example, one trunnion 15 (for example, the right trunnion 15 in FIG. 8) is displaced upward. As the other trunnion 15 (for example, the left trunnion 15 in FIG. 8) is displaced downward, the movements of a pair of trunnions 15 facing each other in the same cavity are synchronized like a seesaw so that they are in the opposite directions. It has the function to displace (for example, refer patent document 1 and patent document 2).

  For example, when the left drive piston 33 in FIG. 8 is displaced downward in the figure and the right drive piston 33 is displaced upward in the figure, the trunnions 15 and 15 coupled to these drive pistons 33 are mutually connected. Displacement is performed in the opposite direction (the left trunnion 15 is displaced downward and the right trunnion 15 is displaced upward), whereby the upper yoke 23A is inclined in the direction in which the right side is up. Similarly, the lower yoke 23B is inclined in the same direction as the upper yoke 23A. Conversely, when the left drive piston 33 in FIG. 8 is displaced upward in the figure and the right drive piston 33 is displaced downward in the figure, the upper yoke 23A is inclined in a direction in which the left side is upward. Similarly, the lower yoke 23B is also inclined in the same direction as the upper yoke 23A.

  Further, the yokes 23A and 23B regulate the tilt angle of the trunnion 15 (and therefore the power roller 11) in addition to the function of synchronizing the axial displacement of the trunnion 15 (and hence the power roller 11) as described above. (See, for example, Patent Document 3 and Patent Document 4).

  The synchronization of the axial displacement of the trunnion 15 and the restriction of the tilt angle are conventionally performed by the axial guide protrusion and the tilt angle restricting protrusion formed on the yokes 23A and 23B. .

Japanese Patent No. 3463625 Japanese Patent No. 3022112 Japanese Patent Laid-Open No. 9-291996 Japanese Patent No. 3417288

  However, if a large number of protrusions, such as an axial guide protrusion and a tilt angle restricting protrusion, are formed on the yokes 23A and 23B, the shapes of the yokes 23A and 23B become complicated. As a result, the yokes 23A and 23B formed by casting or the like are complicated. As a result, it becomes difficult to create the shape, and the reduction of the manufacturing cost is hindered.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an inexpensive toroidal continuously variable transmission that can realize trunnion axial displacement synchronization and tilt angle regulation with a simple yoke structure. And

To achieve the above object, a toroidal-type continuously variable transmission according to the present invention includes a casing and a pair of bearings supported concentrically and rotatably with the inner surfaces facing each other inside the casing. The input side disk and the pair or integral output side disk, a plurality of power rollers sandwiched between these two disks, and a twisted position with respect to the central axis of the input side disk and the output side disk, and A plurality of trunnions that tilt about a pair of concentric shafts provided concentrically with each other and rotatably support the power rollers; a driving device that displaces the trunnions in the axial direction of the pivot; and Each of the pivot shafts of each trunnion is supported so as to be tiltable and axially displaceable, and a pair of yokes that are swung by the displacement of the trunnion With click and, wherein the trunnion support plate portion and a pair of bent wall portions formed on both ends in the longitudinal direction bent to the inner surface side of the supporting plate portion to accommodate the power roller of the support plate portion has the door, a double cavity type toroidal type continuously variable transmission wherein each pivot on the outer surface of each of these bent wall portions are provided concentrically to one another, said yoke has, at its four sides at both ends , A projection that synchronizes the axial displacement of the trunnions by contacting the corresponding trunnion in the axial direction is provided, and this projection also serves as a stopper that regulates the tilt of the trunnion, and the projection is An upper surface that forms a guide surface that abuts the trunnion in the axial direction to synchronize the axial displacement of the trunnions, and a tilt-regulating stop that abuts the trunnion at the maximum speed increase. A first side surface that forms a surface and a second side surface that forms a stopper surface for tilting that contacts the trunnion during maximum deceleration, and the trunnion includes the first and second protrusions The bent wall portion includes a stopper surface that can contact the second side surface, and a guide surface that contacts the upper surface of the protrusion and guides the synchronous operation of the axial displacement of the trunnions in cooperation with the upper surface. It is characterized by being provided in steps .

  According to the present invention, since the projection of the yoke that synchronizes the axial displacement between the trunnions also functions as a stopper for restricting the trunnion tilt, the number of projections provided on the yoke is significantly reduced compared to the conventional one, and the trunnion Thus, the synchronization of the axial displacement and the regulation of the tilt angle can be realized at a low cost with a simple yoke structure. That is, the manufacturing cost can be reduced by simplifying the yoke shape.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The feature of the present invention lies in the structure of the yoke responsible for trunnion axial displacement synchronization and tilt angle regulation, and the other configurations and functions are the same as the conventional configurations and functions described above. Only the characteristic part of the present invention will be described, and the other parts will be simply described with the same reference numerals as those in FIGS.

  1 to 6 show an embodiment of the present invention. As shown in FIGS. 1, 2, and 6, the yokes 23 </ b> A and 23 </ b> B of this embodiment have axial displacements between the trunnions 15 and 15 by abutting the corresponding trunnions 15 in the axial direction at the four ends. A projection 120 for synchronization is provided. Each of these protrusions 120 also has a function as a stopper for restricting the tilt of the trunnion 15.

  That is, the protrusion 120 is in contact with the trunnion 15 in the axial direction to form a guide surface that synchronizes the axial displacement of the trunnions 15 and 15, and the tilt that comes into contact with the trunnion 15 at the maximum acceleration described later. It has the 1st side 120a which forms the stopper surface for control, and the 2nd side 120b which forms the stopper surface for the tilt control which contacts the trunnion 15 at the time of the maximum deceleration mentioned later.

  On the other hand, as shown in FIGS. 2 and 5, each trunnion 15 is in contact with a stopper surface 130 that can contact the first and second side surfaces 120 a and 120 b of the protrusion 120 and an upper surface 120 c of the protrusion 120. In addition, an axial guide surface 140 that guides the synchronous operation of the axial displacement between the trunnions 15 and 15 in cooperation with the upper surface 120 c is provided in a stepped shape on the bent wall portion 20.

  In such a configuration, when the rotational speed of the input shaft 1 and the output shaft is changed, and when deceleration is performed between the input shaft 1 and the output shaft, the pair of drive pistons 33 and 33 are reversed to each other. Displace in the direction. As the drive pistons 33 and 33 are displaced, the pair of trunnions 15 and 15 are displaced in the opposite direction (axial direction) in synchronization with each other. This is realized when the projection 120 of the yoke abuts the axial guide surface 140 of the trunnion 15 in the axial direction. At this time, the upper surface 120c of the protrusion 120 that contacts each other and the axial guide surface 140 of the trunnion 15 cooperate to guide the synchronous movement of the trunnions 15 and 15 in the axial direction. Further, due to the synchronous displacement of the trunnion 15 in the axial direction, the peripheral surfaces 11a and 11a of the power rollers 11 and 11 and the inner surfaces 2a and 2a of the input disks 2 and 2 and the output disks 3 and 3 The direction of the tangential force acting on the contact portion with 3a, 3a changes, and accordingly, each trunnion 15, 15 is centered on the pivots 14, 14 pivotally supported by the yokes 23A, 23B. Tilt in the opposite direction. As a result, the peripheral surfaces 11 a and 11 a of the power rollers 11 and 11 come into contact with a portion near the center of the inner side surface 2 a of the input side disc 2 and a portion near the outer periphery of the inner side surface 3 a of the output side disc 3. In the state shown in FIG. 4 where the deceleration is maximum, the second side surface 120b of the projection 120 of the yoke 23A (23B) and the stopper surface 130 of the trunnion 15 are in contact with each other, and the trunnion 15 is further tilted. Rolling is regulated.

  On the other hand, when increasing the speed, the pair of drive pistons 33, 33 are displaced in the opposite direction to that during deceleration, and the axial displacement of the trunnion 15 is performed as described above. As a result, the peripheral surfaces 11 a and 11 a of the power rollers 11 and 11 come into contact with the outer peripheral portion of the inner side surface 2 a of the input side disc 2 and the central portion of the inner side surface 3 a of the output side disc 3, respectively. In the state shown in FIG. 3 where the speed increase is maximum, the first side surface 120a of the projection 120 of the yoke 23A (23B) and the stopper surface 130 of the trunnion 15 are in contact with each other, and more than that of the trunnion 15. Tilt is regulated.

  As described above, according to the present embodiment, the projection 120 of the yoke 23A (23B) that synchronizes the axial displacement of the trunnions 15 and 15 also functions as a stopper for trunnion tilt regulation. The number of projections provided on (23B) is significantly reduced compared to the conventional case (in this embodiment, only one projection 120 formed on the yoke 23A (23B) is required for one trunnion 15). Thus, the synchronization of the axial displacement and the regulation of the tilt angle can be realized at a low cost with a simple yoke structure. That is, the manufacturing cost can be reduced by simplifying the yoke shape.

  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 which concerns on embodiment of this invention. It is sectional drawing which follows the AA line of FIG. FIG. 3 is a cross-sectional view corresponding to FIG. 2 showing a contact state between a yoke protrusion and a trunnion stopper surface at the maximum speed increase. FIG. 3 is a cross-sectional view corresponding to FIG. 2 showing a contact state between a yoke protrusion and a trunnion stopper surface during maximum deceleration. It is a perspective view of the trunnion which concerns on embodiment of this invention. It is a perspective view of the yoke which concerns on embodiment of this invention. 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.

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 50 Casing 120 Protrusion 120a 1st side surface 120b 2nd side surface 120c Upper surface 130 Stopper surface 140 Axial direction guide surface ( Guide surface)

Claims (1)

A casing, a pair of input-side disks and a pair of or one-piece output-side disks supported concentrically and rotatably with the inner surfaces facing each other inside the casing, and between these two disks A plurality of power rollers sandwiched between and a tilting position about a pair of pivots that are concentrically provided with respect to a central axis of the input side disk and the output side disk, and A plurality of trunnions that rotatably support each power roller, a drive device that displaces each trunnion in the axial direction of the pivot, and the pivots of each trunnion that are tiltable and axially displaceable. as well as, and a pair of yokes which swings by displacement of the trunnion, the trunnion has a length of the support plate portion and the support plate portion A pair of bent wall portions that are formed at both end portions in the direction and are bent toward the inner side surface of the support plate portion so as to accommodate the power roller, and the pivots are mutually connected to the outer side surfaces of the respective bent wall portions. In the double cavity type toroidal continuously variable transmission that is concentrically provided ,
The yoke is provided with projections that synchronize the axial displacement of the trunnions in axial direction with the corresponding trunnions at both ends of the yoke, and these projections serve as stoppers that restrict the inclination of the trunnions. also it serves as a function,
The protrusions form a top surface that forms a guide surface that abuts the trunnion in the axial direction to synchronize the axial displacement of the trunnions, and a tilt-control stopper surface that abuts the trunnion at the maximum speed increase. And a second side surface that forms a stopper surface for tilt regulation that contacts the trunnion during maximum deceleration,
The trunnion includes a stopper surface that can be in contact with the first and second side surfaces of the protrusion, a contact operation with the upper surface of the protrusion, and a synchronous operation of axial displacement between the trunnions in cooperation with the upper surface. A toroidal-type continuously variable transmission, characterized in that a guide surface for guiding is provided in a stepped shape on the bent wall portion .

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