JP3516705B2 - Friction wheel type continuously variable transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction wheel type continuously variable transmission.

[0002]

2. Description of the Related Art A conventional friction wheel type continuously variable transmission is disclosed in Japanese Patent Publication No. 4-502954. The friction wheel type continuously variable transmission shown therein includes an input disc, an output disc, a friction roller arranged in a toroidal groove formed by the discs in frictional contact with the discs, and a friction roller. And a roller supporting member that rotatably supports and that is rotatably supported on a rotating shaft portion orthogonal to the rotating shafts of both discs and movable in the axial direction of the rotating shaft portion. And a piston that is fitted to the cylinder together with a piston shaft that is concentrically and integrally fixed to form a hydraulic cylinder device. The piston is movable in the axial direction of the piston by the hydraulic pressure in the cylinder of the hydraulic cylinder device, whereby the roller support member is movable in the axial direction of the rotary shaft portion. Further, the piston can be integrally rotated by the rotation of the roller supporting member.

[0003]

However, in the conventional friction wheel type continuously variable transmission described above, when hydraulic pressure is supplied into the cylinder of the hydraulic cylinder device to move the piston in the axial direction, the friction roller is provided with both of them. A force is applied to push it out from the disc. As a result, the friction roller does not move in the axial direction of the cylinder due to the balance of the force with the input / output disk, but moves on the center line of the groove formed by both disks. Therefore, in the piston shaft and the piston that are integrally fixed to the rotating shaft portion, these shaft centers are inclined with respect to the cylinder shaft center, oil in the cylinder leaks, the seal is damaged, The piston twists the inner surface of the cylinder, which adversely affects the movement of the roller support member. In order to solve this problem, the rotation shaft and the piston shaft are connected via a ball joint so that the center of rotation of the friction roller can move freely through the ball joint, and the piston's axis is There is a structure that does not cause a deviation from the axis. However,
In this case, since the ball joint has a large diameter ball, the contact area between the ball joint and the rotary shaft portion and the piston is large, so that a large frictional force is generated between them. Therefore, the piston and the piston shaft may rotate, the component force in the radial direction may increase, the piston shaft may largely collapse, and the axial center of the rotating shaft portion may largely deviate from a predetermined position. There is. The present invention is intended to solve such a problem.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a hydraulic cylinder device is arranged such that the axis of the cylinder is inclined with respect to the center line of a groove formed by both disks, and a piston shaft and a roller of the hydraulic cylinder device are arranged. The problem is solved by connecting the rotating shaft of the support member via a plurality of balls. That is, the friction wheel type continuously variable transmission according to the present invention includes an input disk (12, 28) and an output disk (14, 3).
0), a friction roller (16, 32) arranged in a toroidal groove formed by the both discs so as to make frictional contact with the both discs, and a roller rotatably supporting the friction roller (16, 32). What has a support member (42) and the hydraulic cylinder apparatus (41) provided with the piston (48) which can drive the roller support member (42),
The hydraulic cylinder device (41) has a cylinder (6
The shaft center (43) of 2) is arranged at an angle with respect to the center line (45) of the groove formed by the both discs, and the piston shaft (50) of the piston (48) and the roller support member (42). ) Is movably integrally movable in the axial direction via a plurality of balls (54), and is connected so as to be relatively rotatable. The cylinder (62)
Means for restraining the axis of the piston shaft (50) from inclining with respect to the axis (43) of the cylinder (62).
1) can be provided. Also,
The piston shaft (50) and the cylinder (6
Means (84, 86) for restraining relative rotation with respect to (2) may be provided. The numbers in parentheses above are reference numerals of corresponding members in the embodiments described later.

[0005]

When the hydraulic pressure is supplied to the hydraulic cylinder device, the piston and the piston shaft move in the axial direction of the cylinder. As a result, a force for moving the roller support member and the friction roller in the axial direction of the cylinder is applied to the roller support member and the friction roller. Attempt to move along the centerline. Since the roller support member and the piston shaft are connected via a plurality of balls, the roller support
The holding member will be supported on the piston shaft at a plurality of contact points. As a result, the roller supporting member swings about the center of the connecting portion with the piston shaft, so that the friction roller moves so that the rotation center of the friction roller accurately passes through the center line of the groove formed by both discs. Also, roller support
The load that one ball receives from the material and the piston shaft is small, and the contact area between the ball and the roller support member and the piston shaft is small, so the frictional force generated between them is small. As a result, the radial component of the connecting portion between the roller support member and the piston shaft is reduced, so that the axial center of the piston shaft does not deviate from the axial center of the cylinder. Further, rotation of the piston shaft and the piston is suppressed. Therefore, the piston does not twist in the cylinder, the axial center of the piston shaft is inclined with respect to the axial center of the cylinder, the seal member is damaged, and oil does not leak from the cylinder.

[0006]

1 shows a friction wheel type continuously variable transmission according to the present invention.
The first continuously variable transmission mechanism 10 has a first input disk 12, a first output disk 14, and a pair of first friction rollers 16 for transmitting a rotational force between them. First friction roller 16 of first input disk 12 and first output disk 14
The contact surface with is a toroid surface. By changing the contact state of the first friction roller 16 to the first input disk 12 and the first output disk 14, the rotation speed ratio between the first input disk 12 and the first output disk 14 can be continuously changed. The first input disk 12 is the input shaft 1
It is supported on the outer periphery of 8 via a first ball spline 20. A hydraulic cylinder 22 is provided on the back side of the first input disk 12. An oil chamber 24 is configured by the hydraulic cylinder 22 and the back side of the first input disk 12, and by supplying hydraulic pressure to the oil chamber 24, a pressing force is applied to the first input disk 12 in the direction of the first output disk 14. Can act. The second continuously variable transmission mechanism 26 also has a second input disk 28, a second output disk 30, and a pair of second friction rollers 32, which are similar to the first continuously variable transmission mechanism 10. However, the arrangement of the second input disk 28 and the second output disk 30 is opposite to that of the first continuously variable transmission mechanism 10. That is, the first output disk 14 and the second output disk 30 are arranged so as to be adjacent to each other. The second input disc 28 also has a second ball spline 3 on the input shaft 18.
It is connected through 4. A disc spring 36 is provided on the back side of the second input disk 28. Disc spring 36
Is a loading nut 38 screwed onto the input shaft 18.
The compressive force received from gives an initial preload to the first output disk 14 and the second output disk 30 facing the first input disk 12 and the second input disk 28, respectively. The first output disk 14 and the second output disk 30 are rotatably supported on the input shaft 18, respectively, and are driven by the drive gear 4 so as to rotate integrally therewith.
0 is provided.

FIG. 2 is a diagram of the first continuously variable transmission mechanism 10 and a hydraulic cylinder device 41 capable of driving the first continuously variable transmission mechanism 10, and FIG.
-3 shows a sectional view. The second continuously variable transmission mechanism 26 side also has the same structure as the first continuously variable transmission mechanism 10 side. The first friction roller 16 is supported by a roller support member 42 via a bearing 39 so as to be rotatable and vertically movable. The roller support member 42 is connected to the housing 52 of the piston shaft 50 via the self-aligning bearing 46 at the rotary shaft portion 44 thereof so as to be rotatable integrally therewith and also vertically movable integrally therewith. . The self-aligning bearing 46 includes a plurality of small-diameter balls 54, an inner race 56 that rotatably supports the balls 54 on the outer diameter side, and an outer race 58 that rotatably supports the balls 54 on the inner diameter side. It is configured. The inner race 56 is press-fitted onto the outer periphery of the rotary shaft portion 44 and is screwed with a nut 59 to be integrally connected to the rotary shaft portion 44. In addition, the outer race 58 has a housing 52.
The plate 60 that is press-fitted into the inner diameter portion of the housing and has a thread formed on the outer periphery is screwed to the female thread formed on the inner diameter portion of the end portion of the housing 52, and thus is integrally connected to the housing 52. There is. As a result, the self-aligning bearing 46 enables the center of rotation of the first friction roller 16 to move on the center line 45 of the grooves of both disks 12 and 14. The piston shaft 50 includes a lower end of the piston shaft 50 via a bearing (means for restraining inclination of the cylinder 62 with respect to the axial center of the cylinder 62) 61 of the hydraulic cylinder device 41.
2 is inserted into the cylinder 2, is supported such that its axis is concentric with the axis 43 of the cylinder 62, and is movable in the axis direction of the cylinder 62 and relatively rotatable. At the lower end of the piston shaft 50, a nut 64
The piston 48 is fixed by being screwed by. As a result, the piston 48 and the cylinder 6
It is movable in the direction of the axis 2 and relatively rotatable. A first oil chamber 66 and a second oil chamber 68 are formed in the cylinder 62 by the piston 48. First oil chamber 6
By supplying the hydraulic pressure to the sixth or second oil chamber 68, the piston 48 can move in the axial direction of the cylinder 62. The piston 48, the piston shaft 50, and the cylinder 62 form a hydraulic cylinder device 41. Sealing rings 76 and 78 seal between the piston shaft 50 and the cylinder 62 and between the piston 48 and the cylinder 62 to prevent oil from leaking from the first oil chamber 66 and the second oil chamber 68. The hydraulic cylinder device 41 is arranged such that the axis center 43 of the cylinder 62 is inclined by an angle A with respect to the center line 45 of the groove formed by the disks 12 and 14. As a result, the roller support member 42 is also arranged such that the axis thereof is inclined by the angle A with respect to the center line 45 of the groove formed by the disks 12 and 14.

Next, the operation of this embodiment will be described.
Hydraulic pressure is supplied to the first oil chamber 66 or the second oil chamber 68 in order to change gears. As a result, the piston 48 and the piston shaft 50 move diagonally upward or downward in FIG. 2 along the axis 43 of the cylinder 62, so that the roller support member 42 and the first friction roller 16 are provided with these. A force for moving the shaft 43 in the direction of the axis 43 is applied. However, the center of rotation 17 of the first friction roller 16 is moved by the balance between the forces of the first friction roller 16 and the first and second discs 12 and 14.
A force is applied by 14 and 14 to move the groove in the direction of the center line 45. Therefore, the first friction roller 16 swings the rotary shaft portion 44 around the center 70 of the self-aligning bearing 46 of the rotary shaft portion 44 while rotating around the shaft center of the rotary shaft 44 together with the inner race 56. And moves on the center line 45 of the groove formed by both disks 12 and 14. At this time, since the self-aligning bearing 46 is composed of a plurality of balls 54 having a small diameter, the rotating shaft portion 44 can be supported by the housing 52 at a plurality of contact points, so that the first friction roller 16 is provided.
The position of the rotation center 17 of is accurately set. Further, since the self-aligning bearing 46 is composed of a plurality of balls 54, the load received by one ball 54 is small, and the contact area between the self-aligning bearing 46 and the rotating shaft portion 44 and the housing 52 is small. The frictional force generated between them is small. As a result, the radial component of the self-aligning bearing 46 is received by the plurality of small-diameter balls 54, and the piston shaft 50
Since the bearing 61 of the cylinder 62 regulates the inclination of the first friction roller 16,
4 moves along the center line 45 of the groove
The piston shaft 50 and the shaft center thereof do not deviate from the shaft center 43 of the cylinder 62. Therefore, the piston shaft 50 and the piston 48 interfere with the cylinder 62,
Oil does not leak from the cylinder 62. Also,
Since the frictional force generated between the self-aligning bearing 46, the rotating shaft portion 44 and the housing is small, the rotation of the piston shaft 50 and the piston 48 is suppressed. This improves the durability of the seal rings 76 and 78.

FIG. 4 shows a second embodiment. This is the same structure as that of the first embodiment except that the piston shaft 80 and the cylinder 82 are provided with means for restraining the rotation of the piston shaft 80. The tip of the piston shaft 80 is inserted into the rear wall 82a of the cylinder 82 so as to be movable in the axial direction. A groove 84 having a predetermined length in the axial direction is formed in a portion inserted into the rear wall 82a of the piston shaft 80. In the groove 84, FIG.
As shown in FIG. 5, the pin 86 provided on the rear wall 82a penetrates, and thereby a means for restricting the rotation of the piston 80 is configured. That is, the first friction roller 1
When the piston shaft 80 tries to rotate when the 6 rotates, the piston shaft 80 comes into contact with the pin 86, so that the rotation of the piston shaft 80 is restricted. Further, the pin 86 has the groove 8
Since the piston 88 can move relative to the piston shaft 80 by the length dimension of 4, the piston 88 can move in the axial direction by the length dimension of the groove 84.

[0010]

As has been described in the foregoing, according to the present invention, by connecting the piston shaft of the roller support member and the hydraulic cylinder device via a plurality of balls, rollers supported
The holding member is supported on the piston shaft at a plurality of contact points. Therefore, since the roller support member swings around the center of its connecting portion with the piston shaft, the friction roller moves on the center line of the groove formed by both discs, which is the direction of the force generated by the balance of the force with both discs. The rotation center of this can be accurately moved. This improves the controllability. In addition, the load that one ball receives from the roller support member and the piston shaft is small, and the ball and the roller support part
Since the contact area between the material and the housing is small, the frictional force generated between them is small. This allows the roller support
Since the radial component force at the connecting portion between the member and the piston shaft becomes small, the axial center of the piston shaft does not deviate from the axial center of the cylinder. Therefore, the piston shaft and the piston do not tilt and interfere with the cylinder, and the oil in the cylinder does not leak. Also, roller support
Since the frictional force between the material and the ball of the piston shaft is small, the rotation of the piston shaft and the piston is suppressed. Therefore, the durability of the bearing and the seal is improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a first continuously variable transmission mechanism and a hydraulic cylinder device capable of driving the first continuously variable transmission mechanism.

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a diagram showing a second embodiment.

5 is a sectional view taken along line 5-5 of FIG.

[Explanation of symbols]

12 1st input disc (input disc) 14 1st output disc (output disc) 16 First friction roller (friction roller) 28 Second Input Disc (Input Disc) 30 Second output disc (output disc) 32 Second friction roller (friction roller) 41 Hydraulic cylinder device 42 roller support member 43 axis 44 rotating shaft 45 center line 48 pistons 50 piston shaft 54 balls 62 cylinders

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-204311 (JP, A) JP-A 5-87121 (JP, A) Actually open 4-90724 (JP, U) Actually open 61- 73825 (JP, U) Special table 7-508578 (JP, A) Special table 5-508212 (JP, A) Special table 6-507223 (JP, A) Special table 4-502954 (JP, A) US Patent 3413864 (US, A) US Patent 2417948 (US, A) US Patent 1551324 (US, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 15/38 F16J 1/00-1 / 24 F16J 7/00-10/04 F16C 11/00-11/12 F16C 21/00-27/08

Claims (3)

(57) [Claims] 1. An input disk, an output disk, a friction roller disposed in a toroidal groove formed by the disks so as to make frictional contact with the disks, and a roller support for rotatably supporting the friction roller. And a hydraulic cylinder device having a piston capable of driving a roller support member, wherein the hydraulic cylinder device has a cylinder center axis of a groove formed by the two disks. It is arranged at an angle to the line, and the piston shaft of the piston and the roller support member are
A friction wheel type continuously variable transmission characterized by being integrally movable in the axial direction via a plurality of balls and being coupled so as to be rotatable relative to each other. 2. The friction wheel type continuously variable transmission according to claim 1, wherein the cylinder is provided with means for restraining the axis of the piston shaft from inclining with respect to the axis of the cylinder. 3. The friction wheel type continuously variable transmission according to claim 1, wherein the piston shaft is provided with means for restraining relative rotation between the piston shaft and the cylinder.