WO2023248312A1

WO2023248312A1 - Continuously variable transmission

Info

Publication number: WO2023248312A1
Application number: PCT/JP2022/024599
Authority: WO
Inventors: 正太郎山口; 吉洋浅田
Original assignee: 株式会社ユニバンス
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2023-12-28

Abstract

Provided is a continuously variable transmission (10) that can obviate the need for hole punching for providing an oil passage in a cartridge and pipes for conveying the oil to the oil passage of the cartridge. The continuously variable transmission comprises: an axle (11); a first disk (12) that has a curved raceway surface (13), and that integrally rotates with the axle; a second disk (14) having a raceway surface (15) that opposes the raceway surface of the first disk; a roller (25) pressed against the two raceway surfaces; and a carriage (29) that rotatably supports the roller. The axle includes: an oil passage (19) that extends through the inside of the axle in the axial direction; and a plurality of openings (20, 22) that extend from the oil passage to the outside in the radial direction and open to the outside of the axle. The openings are formed at least at the position of the second disk and between the two raceway surfaces.

Description

Continuously variable transmission

The present invention relates to a toroidal continuously variable transmission.

In a toroidal continuously variable transmission, a roller rotatably supported by a carriage is arranged between two disks with curved raceway surfaces facing each other. In a toroidal continuously variable transmission, by changing the inclination of the carriage, the rotation radius of the contact area between each disc and the roller changes, and the gear ratio can be set steplessly. Power transmission between the rollers pressed against the raceway surface of the disk and the disk is achieved by a traction drive that utilizes the viscous shear resistance of the oil film between the raceway surface and the roller. In the prior art disclosed in Patent Document 1, oil (traction oil) is supplied to the rollers from an oil passage provided in the carriage.

Japanese Patent Application Publication No. 2002-276756

The prior art requires drilling to provide an oil passage in the carriage, and also requires piping to send oil to the oil passage provided in the carriage and a device to supply oil to the piping.

The present invention has been made to solve this problem, and provides a continuously variable transmission that eliminates the need for drilling holes to provide oil passages in the carriage, as well as piping and equipment for sending oil to the oil passages of the carriage. The purpose is to

To achieve this objective, the continuously variable transmission of the present invention has a shaft, a first disk having a curved raceway surface and rotating integrally with the shaft, and a raceway surface facing the raceway surface of the first disk. It includes a second disk, a roller that is pressed against two raceway surfaces, and a carriage that rotatably supports the roller. The shaft includes an oil passage extending axially inside the shaft, and a plurality of holes extending radially outward from the oil passage and opening on the outer periphery of the shaft. The hole is open at least at the position of the second disk and between the two raceway surfaces.

According to the first aspect, oil is supplied from an oil path extending axially inside the shaft to a roller disposed between two raceway surfaces through a hole extending radially outward. The rotation of the roller causes oil to accumulate between the roller and the carriage, and the rotating roller supplies oil to the contact area between the first disk and the roller and the contact area between the second disk and the roller. By providing an oil path on the shaft, there is no need to provide an oil path in the carriage to supply oil to the rollers, so it is unnecessary to drill holes in the carriage for the oil path, and to install piping and equipment to send oil to the oil path in the carriage. It can be made unnecessary.

According to the second aspect, in the first aspect, at least two holes that open between the two raceway surfaces are present at positions with different distances between the raceway surface of the first disk and the opening of the hole. do. Therefore, oil can be supplied to different positions of the rollers and carriage.

According to the third aspect, in the first or second aspect, the outer circumferential surface of the roller is pressed against the raceway surface, and the side surface of the roller connected to the outer circumferential surface overlaps the overlapping part of the carriage. The communication portion of the carriage connects to the overlapping portion and overlaps the outer peripheral surface of the roller. A plane perpendicular to the axis passing through the hole opening between the two raceways intersects the overlap. The oil coming out of the holes is supplied to the sides of the rollers. As the rollers are rotating, oil supplied to the sides of the rollers collects in the corner where the overlapping part of the carriage and the connecting part are connected due to centrifugal force. The rollers are cooled by oil supplied through the holes and oil collected in the carriage. Furthermore, the oil accumulated in the carriage allows oil to be efficiently supplied to the contact area between the outer peripheral surface of the roller and the raceway surface.

It is a sectional view of the continuously variable transmission in one embodiment. FIG. 2 is a sectional view of the continuously variable transmission taken along line II-II in FIG. 1. FIG. It is a side view of a roller and a carriage.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of a continuously variable transmission 10 in one embodiment, including a center line O of a shaft 11. The continuously variable transmission 10 illustrated in FIG. 1 is a so-called double cavity full toroidal continuously variable transmission. In FIG. 1, illustration of both sides of the shaft 11 in the axial direction and one side of the support part 37 that supports the carriage 29 in the axial direction are omitted. In this embodiment, a continuously variable transmission 10 that transmits power input to a shaft 11 will be described.

The continuously variable transmission 10 includes a shaft 11 rotationally driven by an engine (not shown), a first disk 12 arranged at two locations on the shaft 11 at intervals in the axial direction, and a curved portion of the first disk 12. between the curved raceway surface 13 of the second disk 14 and the curved raceway surface 15 of the first disk 12; A plurality of (three in this embodiment) rollers 25 are arranged respectively in the rollers 25, and a carriage 29 rotatably supports each of the rollers 25.

The first disk 12 is connected to the shaft 11 by spline connection so that it can slide in the axial direction and rotate integrally with the shaft 11. The first disk 12 is pressed against the second disk 14 by a pressure device (not shown). The second disk 14 is attached to the shaft 11 by a bearing 16 interposed between the second disk 14 and the shaft 11 so as to be rotatable relative to the shaft 11. A rotary body 17 is disposed between the two second disks 14 so as to be rotatable together with the second disk 14 so as to be in contact with the back surfaces of the second disks 14, respectively. The rotating body 17 is attached to the shaft 11 by a bearing 18 interposed between the rotating body 17 and the shaft 11 so as to be rotatable relative to the shaft 11. In this embodiment, the rotating body 17 is a gear.

The shaft 11 has an oil passage 19 extending axially inside the shaft 11 along the center line O, and a plurality of

holes

20, 21, 22, 23 extending from the oil passage 19 toward the outside in the radial direction of the shaft 11. 24. The

holes

20, 21, 22, 23, and 24 are open on the outer periphery of the shaft 11. The oil passage 19 and the

holes

20, 21, 22, 23, and 24 are passages through which oil (traction oil) supplied to each part of the continuously variable transmission 10 flows. The diameter of the oil passage 19 is larger than the diameter of the

holes

20, 21, 22, 23, and 24. When oil is supplied to the oil passage 19, the oil comes out from the

holes

20, 21, 22, 23, and 24.

The hole 20 opens radially inside the bearing 16 disposed between the second disk 14 and the shaft 11. The oil coming out of the hole 20 lubricates the bearing 16. The hole 21 opens on the inside of the bearing 18 in the radial direction, which is disposed between the rotating body 17 and the shaft 11 . The oil coming out of the hole 21 lubricates the bearing 18. The

holes

22 and 23 open between the raceway surface 13 of the first disk 12 and the raceway surface 15 of the second disk 14 (cavity C). The hole 24 is provided between the

holes

22 and 23 and at an intermediate position between the raceway surface 13 of the first disk 12 and the raceway surface 15 of the second disk 14.

The oil coming out of the

holes

22, 23, and 24 spreads into the cavity C in a circular manner due to the rotation of the shaft 11. The oil coming out of the

holes

22, 23, 24 contributes to the formation of an oil film between each

raceway surface

13, 15 and the roller 25, cooling of the roller 25, and lubrication of the bearing 31 disposed at the center of the roller 25. This eliminates the need for drilling to provide oil passages in the carriage 29, piping for supplying oil to the oil passages of the carriage 29, and devices for supplying oil to the piping of the carriage 29.

When a pressurizing device (not shown) is activated and the shaft 11 rotates while pressing the first disk 12 toward the second disk 14, the roller 25 presses the raceway surface 13 of each

disk

12, 14 through an oil film. 15, the torque of the shaft 11 is transmitted to the second disc 14 via the first disc 12 and the roller 25, and further transmitted to the rotating body 17 sandwiched between the second discs 14. The rotating body 17 rotates a driven element (not shown) attached to a shaft (not shown) arranged parallel to the shaft 11 and transmits torque from the shaft 11 to the shaft.

In one cavity C, the distance between the opening of the hole 22 and the raceway surface 13 of the first disk 12 is shorter than the distance between the opening of the hole 23 and the raceway surface 13 of the first disk 12. The distance between the opening of the hole 22 and the raceway surface 13 of the first disk 12 is the same as the distance between the opening of the hole 23 and the raceway surface 15 of the second disk 14. This makes it easier to form an oil film between each

raceway surface

13, 15 and the roller 25.

The diameters of the

holes

22, 23, 24 are larger than the diameters of the holes 20, 21. The diameters of the

holes

22, 23, 24 are all the same. The numbers of

holes

22, 23, and 24 that open in one of the cavities C are all the same. The number of holes 22 opening in one of the cavities C is greater than the number of holes 20 opening in one position of the second disk 14. This allows the amount of oil coming out of the

holes

22, 23, 24 into the cavity C to be greater than the amount of oil supplied to the

bearings

16, 18 from the holes 20, 21.

The roller 25 includes an annular outer circumferential surface 26 that is pressed against the raceway surfaces 13 and 15, and a circular side surface 27 that is connected to the outer circumferential surface 26. A shaft 28 passes through the center of the roller 25, and a bearing 31 is installed between the shaft 28 and the roller 25. An opening 38 is provided on the surface of the shaft 28 facing the shaft 11. The opening 38 is chamfered. The opening 38 is connected to an oil passage 39 provided at the rotation center of the shaft 28. The oil passage 39 is a blind hole. A hole 40 extending radially outward from the oil passage 39 is provided in the shaft 28 . The hole 40 opens radially inside the bearing 31 arranged between the shaft 28 and the roller 25.

The carriage 29 covers a portion of the outer peripheral surface 26 and a portion of the side surface 27 of the roller 25. A support section 37 is fixed to the carriage 29. When the support portion 37 moves, the inclination of the carriage 29 changes, and the radius of rotation of the contact portion between the raceway surfaces 13 and 15 and the outer peripheral surface 26 of the roller 25 changes. As a result, the gear ratio of the continuously variable transmission 10 changes steplessly.

FIG. 2 is a sectional view of the continuously variable transmission 10 taken along line II-II in FIG. 1. FIG. 3 is a side view of the roller 25 and carriage 29. In FIGS. 2 and 3, illustration of a part of the support portion 37 is omitted. The carriage 29 has a cylindrical central portion 30 that fixes the shaft 28 of the roller 25, a first overlapping portion 32 that overlaps the side surface 27 of the roller 25, and an opposite side of the first overlapping portion 32 with the central portion 30 in between. 2nd overlapping part 35 provided in. The first overlapping portion 32 and the second overlapping portion 35 are connected to the central portion 30.

The central portion 30, the first overlapping portion 32, and the second overlapping portion 35 are provided on both sides of the roller 25, respectively. The communication portion 33 overlaps a part of the outer peripheral surface 26 of the roller 25 and connects the two first overlapping portions 32 provided on both sides of the roller 25. A support portion 37 is coupled to the communication portion 33 . The communication portion 36 overlaps a part of the outer peripheral surface 26 of the roller 25 and connects the two second overlapping portions 35 provided on both sides of the roller 25. The

communication portions

33 and 36 are formed when the rotation radius of the contact portion between the raceway surface 13 and the roller 25 and the rotation radius of the contact portion between the raceway surface 15 and the roller 25 are equal in a plane passing through the rotation center of the shaft 28 of the roller 25. They are arranged substantially symmetrically with respect to a plane P1 (see FIG. 3) located perpendicular to the axis 11.

In the first overlapping portion 32, an enlarged portion 32a located farthest from the shaft 28 expands toward the outside in the circumferential direction. The radial length of the enlarged portion 32a is 1/2 or less of the entire radial length of the overlapping portion 32. Since the communication portion 33 connects the portion including the enlarged portion 32a, the circumferential length L1 of the communication portion 33 can be increased by the enlarged portion 32a.

Also in the second overlapping portion 35, the enlarged portion 35a located farthest from the shaft 28 expands toward the outside in the circumferential direction. The radial length of the enlarged portion 35a is 1/2 or less of the entire radial length of the overlapping portion 35. Since the communication portion 36 connects the portion including the enlarged portion 35a, the circumferential length L2 of the communication portion 36 can be increased by the enlarged portion 35a.

The circumferential length L1 of the communication portion 33 is longer than each of the circumferential lengths L3 and L4 of the outer circumferential surface 26 of the roller 25 that does not overlap the carriage 29. Length L1 is shorter than the sum of lengths L3 and L4. The circumferential length L2 of the communication portion 36 is also longer than each of the lengths L3 and L4. Length L2 is shorter than the sum of lengths L3 and L4.

The first overlapping portion 32 is provided with a protrusion 34 that connects the area where the support portion 37 is joined to the center portion 30. The protrusion 34 extends continuously in the axial direction of the support portion 37. The height of the protrusion 34 gradually increases from the outside to the inside of the roller 25 in the radial direction. The mechanical strength of the overlapping portion 32 can be increased by the protrusion 34. The protrusions 34 partition the overlapping portion 32 in the circumferential direction. The shapes and sizes of the two ranges of the overlapping portion 32 circumferentially divided by the protrusion 34 are asymmetrical with respect to the protrusion 34 .

In at least a part of the range in which the radius of rotation of the contact portion between the raceway surfaces 13 and 15 and the roller 25 changes, a plane P2 that is perpendicular to the axis 11 (see FIG. 1) and passes through the openings of the

holes

22 and 23 is It intersects with the first overlapping portion 32 . The oil coming out of the

holes

22, 23 is supplied to the side surface 27 of the roller 25.

Since the roller 25 rotates around the shaft 28, the centrifugal force causes the oil supplied to the side surface 27 of the roller 25 to reach the corner where the first overlapping part 32 and the connecting part 33 of the carriage 29 are connected, and the third part of the carriage 29. The oil collects in the corner where the overlapping portion 35 of the two and the communication portion 36 are connected (hereinafter referred to as an "oil pool"). The roller 25 is cooled by the oil supplied from the

holes

22 and 23 and the oil in the oil reservoir of the carriage 29. Furthermore, the oil supplied from the

holes

22 and 23 and the oil in the oil reservoir of the carriage 29 can efficiently supply oil to the contact portions between the rollers 25 and the raceway surfaces 13 and 15. It is further preferable that the first overlapping portion 32 and the plane P2 intersect in the entire range in which the radius of rotation of the contact portion between the raceway surfaces 13 and 15 and the roller 25 changes.

Since the length L1 of the communication portion 33 and the length L2 of the communication portion 36 are longer than the lengths L3 and L4 of the outer circumferential surface 26 of the roller 25, oil scattering due to rotation of the roller 25 is reduced, and the communication portion Sufficient oil can be stored in the oil reservoir of the carriage 29 including 33 and 36. This prevents the cooling and lubrication efficiency of the roller 25 from decreasing. Since the length L1 of the communication portion 33 and the length L2 of the communication portion 36 are shorter than the combined lengths L3 and L4, the tilted carriage 29 is prevented from interfering with the raceway surfaces 13 and 15 during gear shifting. can.

Since the communication portion 33 connects the portion including the enlarged portion 32a, the circumferential length L1 of the communication portion 33 can be increased by the enlarged portion 32a. Therefore, the oil reservoir in the carriage 29 can be enlarged by the enlarged portion 32a. Furthermore, since the area of the overlapped portion 32 other than the enlarged portion 32a can be reduced, the area of the side surface 27 of the roller 25 where the overlapped portion 32 does not overlap and oil is supplied from the

holes

23 and 24 can be secured. can. Thereby, the amount of oil supplied to the side surface 27 of the roller 25 can be ensured, and the amount of oil carried to the oil reservoir of the carriage 29 by centrifugal force can be ensured.

Similarly, since the connecting portion 36 connects the portion including the enlarged portion 35a, the circumferential length L2 of the connecting portion 36 can be increased by the enlarged portion 35a. Therefore, the oil reservoir in the carriage 29 can be enlarged by the enlarged portion 35a. Furthermore, since the area of the overlapped portion 35 other than the enlarged portion 35a can be reduced, the area of the side surface 27 of the roller 25 where the overlapped portion 35 does not overlap and oil is supplied from the

holes

A hole 40 that connects to a bearing 31 disposed between the shaft 28 of the roller 25 and the roller 25 and an oil passage 39 that connects to the hole 40 are provided in the shaft 28 . It is provided on the surface facing the axis 11. Since a hole 24 is provided in the shaft 11 at an intermediate position between the raceway surface 13 of the first disk 12 and the raceway surface 15 of the second disk 14, some of the oil coming out of the hole 24 is drained from the opening 38. It enters channel 39 and is supplied to bearing 31 through hole 40 . Therefore, the bearing 31 can be lubricated. Since the opening 38 is chamfered, the oil coming out of the hole 24 can easily enter the oil passage 39.

Since the ridges 34 are provided on the overlapped portion 32, oil can be easily stored in the corners of the center portion 30 and the ridges 34 in the overlapped portion 32, compared to a case where the ridges 34 are not provided. Since oil can be more easily placed near the rotation center of the roller 25, it becomes easier to lubricate the bearing 31 provided at the center of the roller 25.

Although the present invention has been described above based on the embodiments, the present invention is not limited to these embodiments in any way, and it is easily understood that various improvements and modifications can be made without departing from the spirit of the present invention. This can be inferred. The positions, sizes, numbers, etc. of the

holes

20, 21, 22, 23, 24 provided in the shaft 11 can be set as appropriate.

In the embodiment, a case has been described in which the

communication parts

33 and 36 are arranged substantially symmetrically with respect to the plane P1 (see FIG. 3), but the invention is not necessarily limited to this. Making the

communication parts

33 and 36 asymmetrical with respect to the plane P1, for example, making the downstream side of the rotation direction of the roller 25 (second disk 14 side) longer with respect to the rotation center of the shaft 28, or extending it toward the raceway surface 15. is of course possible.

In the embodiment, a case has been described in which the oil passage 39 and the hole 40 are provided in the shaft 28 of the roller 25, but the invention is not necessarily limited to this. It is of course possible to omit the oil passage 39 and hole 40 provided in the shaft 28. When the oil passage 39 and hole 40 are omitted, the hole 24 provided in the shaft 11 can be omitted.

In the embodiment, a fully toroidal continuously variable transmission has been described, but the present invention is not necessarily limited to this. It is of course possible to apply it to a half-toroidal continuously variable transmission. Further, in the embodiment, a double-cavity continuously variable transmission has been described, but the present invention is not necessarily limited to this. It is of course possible to apply the present invention to a single-cavity continuously variable transmission.

In the embodiment, a case has been described in which the rotating body 17 provided on the shaft 11 is a gear, and the gear of a driven element (not shown) provided on the shaft meshes with the rotating body 17 to transmit power, but this is not necessarily the case. It is not limited to. For example, it is of course possible to provide a sprocket on the rotating body 17 provided on the shaft 11 and to interpose a chain between it and the sprocket of a driven element (not shown) provided on the shaft to transmit power.

In the embodiment, a case has been described in which the power input to the shaft 11 is output from the rotating body 17, but the invention is not necessarily limited to this. Of course, it is possible to output the power input from the rotating body 17 from the shaft 11.

10 Continuously variable transmission 11 Shaft 12 First disk 13 Raceway surface 14 Second disk 15 Raceway surface 19

Oil passage

20, 22, 23, 24 Hole 25 Roller 26 Outer surface 27 Side surface 29 Carriage 32 First overlapping portion 33 Communication portion 35 Second overlapping part 36 Communication part P2 plane

Claims

axis and
a first disk having a curved orbital surface and rotating integrally with the shaft;
a second disk having a raceway surface opposite to the raceway surface;
a roller pressed against the two raceway surfaces;
a carriage rotatably supporting the roller;
The shaft includes an oil passage extending in the axial direction inside the shaft;
a plurality of holes extending radially outward from the oil passage and opening on the outer periphery of the shaft;
In the continuously variable transmission, the hole is open at least at the position of the second disk and between the two raceway surfaces.
2. The continuously variable transmission according to claim 1, wherein at least two of the holes opening between the two raceway surfaces exist at positions with different distances between the raceway surface of the first disk and the opening of the hole. Machine.
The roller includes an annular outer peripheral surface pressed against the raceway surface and a circular side surface connected to the outer peripheral surface,
The carriage includes an overlapping part that overlaps the side surface, and a communication part that is connected to the overlapping part and overlaps the outer peripheral surface,
The continuously variable transmission according to claim 1 or 2, wherein a plane perpendicular to the axis that passes through an opening of the hole existing between the two raceway surfaces intersects with the overlapping portion.