WO2017199941A1

WO2017199941A1 - Traction speed reducer and electric motor–equipped speed reducer

Info

Publication number: WO2017199941A1
Application number: PCT/JP2017/018327
Authority: WO
Inventors: 正今村
Original assignee: 日本電産シンポ株式会社
Priority date: 2016-05-16
Filing date: 2017-05-16
Publication date: 2017-11-23

Abstract

This traction speed reducer is provided with: a sun roller that rotates about an axis of rotation; a plurality of planetary rollers that are disposed around the sun roller; a pair of annular internal rings that are in contact with the plurality of planetary rollers; and a carrier that holds the planetary rollers and rotates about the axis of rotation. The plurality of planetary rollers are each in contact with the sun roller and both of the internal rings, and by receiving motive power from the sun roller, orbit around the axis of rotation while rotating independently. The carrier has a contact surface facing the outer circumferential surface of the planetary rollers, and the contact surface and the outer circumferential surface of the planetary rollers are in contact in the circumferential direction about the axis of rotation. As a result, a carrier pin for rotatably supporting the planetary rollers is unnecessary. Thus, it is possible to reduce the number of components and decrease the size of the traction speed reducer.

Description

Traction reducer and reducer with electric motor

The present invention relates to a traction speed reducer and a speed reducer with an electric motor.

Conventionally, there is known a traction reducer that uses the traction (friction) generated between the sun roller and the planetary roller to reduce the rotational speed of the input shaft and rotate the output shaft. Such a traction reducer is described in, for example, Japanese Patent Application Laid-Open No. 2009-138924.

The traction power transmission device described in the document includes a sun roller that is rotatable around a first central axis, and a plurality of second central axes that are arranged on a plurality of peripheral axes that are parallel to the first central axis. The shaft member, a plurality of planetary rollers rotatably provided along the peripheral surface of the sun roller while being supported by the shaft member, and the parallelism between the first central axis and the second central axis is maintained The planetary roller is pressed against the circumferential surface of the sun roller by guiding the shaft member so as to be movable in the radial direction of the sun roller, and power transmission by traction is enabled between the sun roller and the planetary roller. A pressing member.

In this document, since the shaft member, which is the rotation center of the planetary roller, moves in the radial direction of the sun roller, a force that presses the planetary roller against the circumferential surface of the sun roller acts, thereby Describes that traction can be generated. Furthermore, even if the planetary roller moves in the radial direction of the sun roller, the rotation center of the planetary roller always keeps parallel to the rotation center of the sun roller, so that traction can be generated evenly in the axial direction. (See paragraphs 0007 to 0008, etc.).
JP 2009-138924 A

However, in the structure described in Japanese Patent Application Laid-Open No. 2009-138924, it is necessary to dispose the pressing surface of the planetary gear by the pressing portion on the radially outer side than the shaft member. Further, it is necessary to provide a pressing surface of the planetary roller separately from the shaft member. For this reason, it is difficult to reduce the size of the traction reducer in the radial direction.

An object of the present invention is to provide a technology capable of reducing the number of parts and reducing the size of a traction reducer in a traction reducer.

An exemplary first invention of the present application is a traction speed reducer, which is a sun roller that rotates about a rotation axis, a plurality of planetary rollers arranged around the sun roller, and a contact with the plurality of planetary rollers. A pair of annular internal rings and a carrier that rotates around the rotation axis while holding the planetary roller, and the plurality of planetary rollers are respectively the sun roller and the internal ring. The carrier revolves around the rotation axis while rotating by receiving power from the sun roller while being in contact with both the carrier, the carrier has a contact surface facing the outer peripheral surface of the planetary roller, and the planet The outer peripheral surface of the roller and the contact surface are in contact with each other in the circumferential direction around the rotation axis.

According to the first exemplary invention of the present application, a carrier pin that supports each planetary roller so as to rotate is not necessary. For this reason, the number of parts can be reduced and the traction speed reducer can be miniaturized.

FIG. 1 is a perspective view of a reduction gear with an electric motor according to the first embodiment. FIG. 2 is a longitudinal sectional view of the reduction gear with an electric motor according to the first embodiment. FIG. 3 is a cross-sectional view of the traction reducer according to the first embodiment. FIG. 4 is a cross-sectional view of the traction reducer according to the first embodiment. FIG. 5 is a cross-sectional view of the traction reducer according to the first embodiment. FIG. 6 is a longitudinal sectional view of a reduction gear with an electric motor according to the second embodiment. FIG. 7 is a cross-sectional view of the traction reducer according to the second embodiment. FIG. 8 is a cross-sectional view of a traction reducer according to the second embodiment. FIG. 9 is a partial longitudinal sectional view of a reduction gear with an electric motor according to the third embodiment.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In the present application, the direction parallel to the rotation axis of the sun roller is “axial direction”, the direction orthogonal to the rotation axis is “radial direction”, and the direction along the arc centered on the rotation axis is “circumferential direction”. Called. However, the above “parallel direction” includes a substantially parallel direction. In addition, the above-mentioned “orthogonal direction” includes a substantially orthogonal direction. In the following, for convenience of explanation, the right side in FIG. 1 is referred to as “input side” and the left side in FIG. 1 is referred to as “output side”.

FIG. 1 is a perspective view of a reduction gear 10 with an electric motor including a traction reduction gear 1 according to the present embodiment. FIG. 2 is a longitudinal sectional view of the reduction gear 10 with an electric motor including the traction reduction gear 1 according to the present embodiment. The motor-equipped speed reducer 10 is a speed reducer that rotates the output shaft 90 by converting the rotational motion of the first rotational speed obtained from the motor 11 into the rotational motion of the second rotational speed lower than the first rotational speed. is there. The traction reduction gear 1 and the reduction gear 10 with an electric motor of the present invention are used, for example, for precision parts of electrical appliances.

As shown in FIGS. 1 and 2, the speed reducer 10 with an electric motor according to the present embodiment includes a motor 11, a mounting plate 12, and a traction speed reducer 1.

The motor 11 is an electric motor that is a power source of the reduction gear 10 with an electric motor. The motor 11 is connected to the sun roller 20 of the traction speed reducer 1 described later. When the motor 11 is driven, the sun roller 20 rotates around the rotation shaft 9.

The mounting plate 12 is a plate-like member for mounting the traction speed reducer 1 to the motor 11. The mounting plate 12 is disposed substantially perpendicular to the rotation shaft 9. The mounting plate 12 is fixed to a motor casing that is an outer frame of the motor 11. The motor casing and the mounting plate 12 are fixed by a fixing tool such as a screw. However, the motor casing and the mounting plate 12 may be fixed by other methods.

The traction speed reducer 1 is a device that decelerates the rotational motion of the motor 11 and transmits it to the output shaft 90. The traction speed reducer 1 is a so-called traction type planetary that transmits power by rotating the outer circumferential surface of the sun roller 20 and the outer circumferential surfaces of the plurality of planetary rollers 30 in contact with each other without using gears. A reduction mechanism is used.

As shown in FIG. 2, the traction speed reducer 1 according to the present embodiment includes one sun roller 20, a plurality of planetary rollers 30, an internal ring 40, a carrier 50, a carrier bearing 60, an elastic member 70, a housing 80, and an output shaft. 90.

The sun roller 20 is a columnar member arranged coaxially with the rotary shaft 9. The sun roller 20 is connected to the motor 11 located on the input side in the axial direction. When the motor 11 is driven, the sun roller 20 rotates at the first rotation speed around the rotation shaft 9 by the power received from the motor 11. In the present embodiment, the output shaft of the motor 11 is the sun roller 20. Thus, if the output shaft of the motor 11 and the sun roller 20 are made into a single part, the number of parts of the reduction gear 10 with an electric motor will reduce. Therefore, it becomes easy to miniaturize the reduction gear 10 with an electric motor. However, a sun roller that rotates together with the output shaft may be provided separately from the output shaft of the motor 11.

FIG. 3 is a cross-sectional view of the traction reducer 1 taken along the line AA in FIG. The plurality of planetary rollers 30 are arranged around the sun roller 20. As shown in FIG. 3, in the present embodiment, three planetary rollers 30 are arranged around the sun roller 20 at equal intervals in the circumferential direction.

Each of the plurality of planetary rollers 30 includes a disk portion 31 and a pair of shaft portions 32. The disc portion 31 is arranged around the sun roller 20 so that a straight line connecting the center viewed from the axial input side and the center viewed from the axial output side is parallel to the rotation shaft 9. Is done. As shown in FIGS. 2 and 3, the outer peripheral portion of the disc portion 31 is in contact with the outer peripheral portion of the sun roller 20. The pair of shaft portions 32 extend in parallel with the rotation shaft 9 from the center of the disc portion 31 to the input side and output side in the axial direction. In this embodiment, the disc part 31 and a pair of axial part 32 are comprised by one member. Each shaft portion 32 has an annular inclined surface 33 at the end opposite to the axial disk portion 31. The inclined surface 33 is inclined with respect to the axial direction so as to decrease in diameter toward the tip of the shaft portion 32. The disk portion 31 only needs to have a circular outer periphery when viewed from the axial direction, and the surface shape may be other than a plate shape.

The internal ring 40 is a pair of annular members that contact the plurality of planetary rollers 30. The internal ring 40 according to this embodiment includes a fixed internal ring 41 and a movable internal ring 42. As shown in FIG. 2, the fixed internal ring 41 of the present embodiment is positioned on the input side in the axial direction with respect to the disc portion 31, and the position in the axial direction is fixed. The movable internal ring 42 is positioned on the output side in the axial direction with respect to the disc portion 31 and is movable in the axial direction. However, the movable internal ring 42 may be disposed on the input side in the axial direction with respect to the disc portion 31, and the fixed internal ring 41 may be disposed on the output side in the axial direction with respect to the disc portion 31.

FIG. 4 is a cross-sectional view of the traction reducer 1 taken along the line BB in FIG. The plurality of planetary rollers 30 are rotatably supported around the sun roller 20 by the sun roller 20 and the internal ring 40. As shown in FIG. 4, the outer peripheral portions of the plurality of planetary rollers 30 are in contact with the inner peripheral portion of the internal ring 40. When the sun roller 20 rotates about the rotation shaft 9, the plurality of planetary rollers 30 receives power from the sun roller 20. The plurality of planetary rollers 30 revolve around the rotating shaft 9 while rotating around the sun roller 20.

Further, as shown in FIG. 2, the internal ring 40 of the present embodiment is in contact with the inclined surface 33 of the shaft portion 32. Thereby, the internal ring 40 and the planetary roller 30 can be contacted, suppressing the radial width. Further, since the disk portion 31 and the shaft portion 32 of the planetary roller 30 are the same member, the internal ring 40 is not provided with a separate contact member between the internal ring 40 and the planetary roller 30. Can be transmitted directly to the planetary roller 30. As a result, the number of parts of the traction reduction gear 1 can be reduced.

FIG. 5 is a cross-sectional view taken along the line CC of FIG. The carrier 50 rotates around the rotation shaft 9 while holding the plurality of planetary rollers 30. As shown in FIG. 5, the carrier 50 has a contact surface 54 that faces the outer peripheral surface of the shaft portion 32 of the planetary roller 30. Of the outer peripheral surface of the shaft portion 32, at least a part of the surface located on the front side in the rotational direction of the revolution of the planetary roller 30 and the contact surface 54 are in contact in the circumferential direction. That is, the contact surface 54 and at least a part of the outer peripheral surface of the shaft portion 32 are in contact with each other in the circumferential direction around the rotation shaft 9. Accordingly, each planetary roller 30 is supported around the sun roller 20 so as to be capable of rotating. Thus, the shaft portion 32 that is a part of the planetary roller 30 is supported by the carrier 50. For this reason, it is not necessary to separately provide a member such as a carrier pin. As a result, the number of parts can be reduced and the traction speed reducer 1 can be downsized.

Further, as shown in FIGS. 2, 4, and 5, the carrier 50 of the present embodiment has a plurality of accommodating portions 56. The plurality of accommodating portions 56 are arranged in the circumferential direction around the rotation shaft 9, and each of the accommodating portions 56 is open radially outward. The shaft portions 32 of the plurality of planetary rollers 30 are accommodated in the accommodating portion 56. For this reason, the planetary roller 30 can be inserted into the accommodating portion 56 of the carrier 50 from the outside in the radial direction when the traction reduction gear 1 is manufactured. Thereby, the assembly of the traction reduction gear 1 becomes easy.

In addition, the carrier 50 of this embodiment is comprised with a single member. For this reason, the number of parts can be reduced as compared with the case where the carrier 50 is constituted by a plurality of members. Thereby, the traction reduction gear 1 can be further reduced in size. Moreover, the assembly of the traction speed reducer 1 becomes easier.

The carrier bearing 60 supports the carrier 50 so as to be rotatable about the rotary shaft 9. As shown in FIG. 2, the carrier bearing 60 of the present embodiment contacts at least a part of the outer peripheral surface of the carrier 50. Further, the carrier bearing 60 is in contact with the end face on the output side in the axial direction of the carrier 50. Thereby, the movement of the radial direction and the axial direction is regulated and the carrier 50 is stably held.

The elastic member 70 is a member that pressurizes the movable internal ring 42 toward the input side in the axial direction. The elastic member 70 is an annular member that expands and contracts in the axial direction. For the elastic member 70, for example, a wave spring is used. The elastic member 70 is disposed between the carrier bearing 60 and the movable internal ring 42 in a state compressed in the axial direction rather than the natural length. For this reason, the movable internal ring 42 is pressurized to the input side by the repulsive force of the elastic member 70.

As described above, the fixed internal ring 41 and the movable internal ring 42 are in contact with the inclined surface 33 of the shaft portion 32 of the planetary roller 30. For this reason, when the movable internal ring 42 is pressurized toward the input side in the axial direction, the shaft portion 32 receives a pressing force toward the radially inner side via the inclined surface 33. That is, the plurality of planetary rollers 30 are pressed radially inward by the fixed internal ring 41 and the movable internal ring 42.

Further, the elastic member 70 of the present embodiment is disposed in a space on the outer side in the radial direction of the carrier 50. Thereby, the dimension of the axial direction of the traction reduction gear 1 can be reduced rather than the case where the carrier 50 and the elastic member 70 are arrange | positioned in a different axial direction position. As a result, the traction speed reducer 1 can be further downsized.

The housing 80 is a member that accommodates at least the sun roller 20, the plurality of planetary rollers 30, the pair of internal rings 40, the carrier 50, and the carrier bearing 60 therein. The housing 80 has a cylindrical inner peripheral surface surrounding at least the outer periphery of the internal ring 40.

As shown in FIG. 2, the housing 80 of the present embodiment has a claw portion 81 that extends radially inward. The claw portion 81 is formed, for example, by caulking a part in the circumferential direction of the output side end edge of the housing 80. The claw portion 81 contacts the carrier bearing 60 in the axial direction. Thereby, the axial positioning of the carrier bearing 60 with respect to the housing 80 can be easily performed. As a result, the traction speed reducer 1 can be easily assembled. Further, the claw portion 81 is in contact with the carrier bearing 60 and the circumferential direction around the rotation shaft 9. Thereby, relative rotation of the carrier bearing 60 with respect to the housing 80 can be easily prevented.

Further, as shown in FIG. 4, the internal ring 40 of the present embodiment has a plurality of first anti-rotation portions 43 that are recessed inward in the radial direction in a part of the outer peripheral surface and whose surface is a flat portion. Further, the housing 80 of the present embodiment has a plurality of second anti-rotation portions 82 that are convex inward in the radial direction and whose inner surface in the radial direction is a flat portion. The plurality of first detent portions 43 are arranged at equal intervals in the circumferential direction around the rotation shaft 9. The plurality of second anti-rotation portions 82 are arranged at equal intervals in the circumferential direction around the rotation shaft 9. The first anti-rotation portion 43 is fitted into the second anti-rotation portion 82, and the flat portion of the first anti-rotation portion 43 and the flat portion of the second anti-rotation portion 82 are in contact with each other. Thereby, relative rotation of the internal ring 40 with respect to the housing 80 can be prevented. As a result, the rotation of the planetary roller 30 and the carrier 50 is stabilized.

Note that the plurality of first detent portions 43 may be formed so that a part of the outer peripheral surface of the internal ring 40 is a non-perfect circle, and is not limited to the structure of FIG. Further, the plurality of second anti-rotation portions 82 may be formed so that a part of the inner peripheral surface of the housing 80 is a non-circular shape, and is not limited to the structure of FIG.

The output shaft 90 is a columnar member that extends to the output side in the axial direction along the rotation shaft 9. The output shaft 90 is fixed, for example, by being press-fitted from an end on the output side in the axial direction of the carrier 50 into a recess 55 that is recessed on the input side in the axial direction. However, other methods may be used for fixing the output shaft 90 and the carrier 50. The output shaft 90 rotates around the rotation shaft 9 together with the carrier 50.

The plurality of planetary rollers 30 are always in contact with the sun roller 20, the fixed internal ring 41, and the movable internal ring 42, respectively. A lubricant (not shown) is interposed between the sun roller 20 and the planetary roller 30. Thereby, traction is generated between the sun roller 20 and the planetary roller 30. A lubricant (not shown) is interposed between the planetary roller 30 and the internal ring 40. As a result, traction is generated between the planetary roller 30 and the internal ring 40. When the sun roller 20 is rotated by the driving force of the motor 11, the plurality of planetary rollers 30 receive power from the sun roller 20 and rotate by traction with the sun roller 20. Further, the plurality of planetary rollers 30 revolve around the rotating shaft 9 along the internal ring 40 by traction with the internal ring 40. At this time, the revolution speed of the planetary roller 30 is a second rotational speed lower than the first rotational speed.

When the plurality of planetary rollers 30 revolve at the second rotational speed after deceleration, the carrier 50 also rotates at the second rotational speed around the rotation shaft 9. When the carrier 50 is rotated, the output shaft 90 fixed to the carrier 50 is also rotated at the second rotation speed around the rotation shaft 9. Thereby, the rotational motion at the first rotational speed of the motor 11 is converted into the rotational motion at the second rotational speed that is lower than the first rotational speed, and is output to the output shaft 90.

Next, a reduction gear 10A with an electric motor and a traction reduction gear 1A according to a second embodiment will be described. FIG. 6 is a longitudinal sectional view of a reduction gear with an electric motor including a traction reduction gear 1A according to the second embodiment. FIG. 7 is a DD cross-sectional view of FIG. 6 of the traction reducer 1A according to the second embodiment. FIG. 8 is a cross-sectional view taken along the line EE of FIG. 6 of the traction reducer 1A according to the second embodiment.

Similar to the reduction gear with motor 10 according to the first embodiment, this reduction gear with motor 10A rotates the rotation motion at the first rotation speed obtained from the motor 11A at the second rotation speed lower than the first rotation speed. It is a speed reducer that converts the motion to rotate the output shaft 90A.

As shown in FIG. 6, the traction reduction gear 1A of this embodiment includes one sun roller 20A, a plurality of planetary rollers 30A, an internal ring 40A, a carrier 50A, a carrier bearing 60A, an elastic member 70A, a housing 80A, and an output shaft. 90A.

The sun roller 20A is a columnar member arranged coaxially with the rotating shaft 9A. The sun roller 20A is connected to a motor 11A located on the input side in the axial direction. When the motor 11A is driven, the sun roller 20A rotates at the first rotation speed around the rotation shaft 9A by the power received from the motor 11A.

Each of the plurality of planetary rollers 30A has a disk portion 31A and a pair of shaft portions 32A. The disc portion 31A is arranged around the sun roller 20A so that a straight line connecting the center viewed from the axial input side and the center viewed from the axial output side is parallel to the rotation shaft 9A. Is done. As shown in FIGS. 6 and 7, the outer peripheral portion of the disc portion 31A is in contact with the outer peripheral portion of the sun roller 20A. The pair of shaft portions 32A extends parallel to the rotation shaft 9A from the center of the disc portion 31A to the input side and output side in the axial direction. Each shaft portion 32A has an annular inclined surface 33A at the end opposite to the axial disk portion 31A. The inclined surface 33A is inclined with respect to the axial direction so as to decrease in diameter toward the tip of the shaft portion 32A. The disk portion 31A only needs to have a circular outer periphery when viewed from the axial direction, and the surface shape may be other than a plate shape.

The internal ring 40A is a pair of annular members that are in contact with the plurality of planetary rollers 30A. The internal ring 40A of the present embodiment includes a fixed internal ring 41A and a movable internal ring 42A. As shown in FIG. 6, the fixed internal ring 41A of the present embodiment is positioned on the output side in the axial direction from the disk portion 31A, and the position in the axial direction is fixed. The movable internal ring 42A is positioned on the input side in the axial direction with respect to the disc portion 31A, and is movable in the axial direction.

The plurality of planetary rollers 30A are rotatably supported around the sun roller 20A by the sun roller 20A and the internal ring 40A. Further, the outer peripheral portions of the plurality of planetary rollers 30A are in contact with the inner peripheral portion of the internal ring 40A. For this reason, when the sun roller 20A rotates around the rotation shaft 9A, the plurality of planetary rollers 30A receive power from the sun roller 20A. The plurality of planetary rollers 30A revolve around the rotating shaft 9A while rotating around the sun roller 20A. The internal ring 40A of this embodiment is in contact with the inclined surface 33A of the shaft portion 32A, as in the first embodiment.

The carrier 50A rotates around the rotation shaft 9A while holding the plurality of planetary rollers 30A. The carrier 50A of the present embodiment has two

first carrier members

511A and 512A, a second carrier member 52A, and a plurality of carrier poles 53A.

The first carrier member 51A is a disk-shaped member having a contact surface 54A. As shown in FIGS. 6 and 8, one of the two first carrier members 511A has at least part of the outer peripheral surface of the shaft portion 32A on the output side in the axial direction of the planetary roller 30A and the contact surface 54A. The contact is made in the circumferential direction around the rotating shaft 9A. The other first carrier member 512A is arranged in the circumferential direction centering on the rotating shaft 9A via at least a part of the outer circumferential surface of the shaft portion 32A on the input side in the axial direction of the planetary roller 30A and the contact surface 54A. Contact. Thereby, each planetary roller 30A is supported so that it can rotate around the sun roller 20A. The second carrier member 52A is disposed on the output side in the axial direction with respect to the

first carrier members

511A and 512A and the planetary roller 30A.

The carrier pole 53A is a columnar member extending in the axial direction. As shown in FIG. 7, in this embodiment, three carrier poles 53A are arranged at equal intervals in the circumferential direction around the sun roller 20A and between the planetary rollers 30A. The end portion on the input side in the axial direction of the carrier pole 53A is fixed to the first carrier member 51A. Further, the end on the output side in the axial direction of the carrier pole 53A is fixed to the second carrier member 52A. As a result, the first carrier member 51A and the second carrier member 52A rotate around the rotation shaft 9A as the planetary roller 30A rotates.

The carrier bearing 60A supports the second carrier member 52A so as to be rotatable about the rotation shaft 9A. As shown in FIG. 6, the carrier bearing 60A of the present embodiment is in contact with at least a part of the outer peripheral surface of the carrier 50A. Furthermore, the carrier bearing 60A is in contact with the end face on the output side in the axial direction of the carrier 50A. Thereby, the carrier 50A is restricted from moving in the radial direction and the axial direction, and is stably held.

The elastic member 70A is a mechanism that pressurizes the movable internal ring 42A toward the output side in the axial direction. The elastic member 70A is an annular member that expands and contracts in the axial direction. For the elastic member 70, for example, a wave spring is used. The elastic member 70A is disposed between the mounting plate 12A and the movable internal ring 42A in a state compressed in the axial direction rather than the natural length. For this reason, the movable internal ring 42A is pressurized toward the output side by the repulsive force of the elastic member 70A. When the movable internal ring 42A is pressurized toward the output side in the axial direction, the shaft portion 32A receives a pressing force toward the radially inner side via the inclined surface 33A. That is, the plurality of planetary rollers 30A are pressed radially inward by the fixed internal ring 41A and the movable internal ring 42A.

The housing 80A is a member that accommodates at least the sun roller 20A, the plurality of planetary rollers 30A, the pair of internal rings 40A, the carrier 50A, and the carrier bearing 60A.

The output shaft 90A is a columnar member that extends to the output side in the axial direction along the rotation shaft 9A. The output shaft 90A is fixed, for example, by being press-fitted into a through hole 55A provided in the center of the second carrier member 52A. The output shaft 90A rotates around the rotation shaft 9A together with the second carrier member 52A.

As shown in FIG. 6, the internal ring 40 </ b> A of the present embodiment has a plurality of first detent portions 43 </ b> A that are non-circular on a part of the outer peripheral surface. Further, the housing 80A of the present embodiment has a plurality of second anti-rotation portions 82A that are non-circular on a part of the inner peripheral surface. The plurality of first detent portions 43A are arranged at equal intervals in the circumferential direction around the rotation shaft 9A. The plurality of second anti-rotation portions 82A are arranged at equal intervals in the circumferential direction around the rotation shaft 9A. The first detent portion 43A comes into contact with the second detent portion 82A. Thereby, the circumferential positioning of the carrier 50A with respect to the housing 80A can be facilitated. As a result, the traction reduction gear 1A can be easily assembled. Further, relative rotation of the internal ring 40A with respect to the housing 80A can be prevented. As a result, the rotation of the planetary roller 30A and the carrier 50A is stabilized.

The plurality of planetary rollers 30A are always in contact with the sun roller 20A, the fixed internal ring 41A, and the movable internal ring 42A, respectively. A lubricant (not shown) is interposed between the sun roller 20A and the planetary roller 30A. Thereby, traction is generated between the sun roller 20A and the planetary roller 30A. A lubricant (not shown) is interposed between the planetary roller 30A and the internal ring 40A. As a result, traction is generated between the planetary roller 30 and the internal ring 40. When the sun roller 20A is rotated by the driving force of the motor 11A, the plurality of planetary rollers 30A receives power from the sun roller 20A and rotates by traction with the sun roller 20A. The plurality of planetary rollers 30A revolve around the rotating shaft 9A along the internal ring 40A by traction with the internal ring 40A. At this time, the revolution speed of the planetary roller 30 </ b> A is a second rotational speed lower than the first rotational speed.

When the plurality of planetary rollers 30A revolves at the second rotational speed after deceleration, the second carrier member 52A fixed to the carrier pole 53A together with the first carrier member 51A also has the second center around the rotation shaft 9A. Rotates at the number of revolutions. The output shaft 90A fixed to the second carrier member 52A also rotates at the second rotation speed about the rotation shaft 9A. Thereby, the rotational motion at the first rotational speed of the motor is converted into the rotational motion at the second rotational speed lower than the first rotational speed, and is output to the output shaft 90A.

Next, a reduction gear 10B with an electric motor and a traction reduction gear 1B according to a third embodiment will be described. FIG. 9 is a partial longitudinal sectional view of a reduction gear 10B with an electric motor including a traction reduction gear 1B according to the third embodiment. In the following description, differences from the first embodiment will be mainly described, and redundant description of parts equivalent to those of the first embodiment will be omitted.

This reduction gear 10B with an electric motor, like the reduction gear 10 with an electric motor according to the first embodiment, performs a rotational motion at a first rotational speed obtained from a motor (not shown) in a second rotation lower than the first rotational speed. This is a speed reducer that converts the rotational motion into a number and rotates the output shaft 90B.

As shown in FIG. 9, the carrier bearing 60B of the traction reduction gear 1B according to the present embodiment has a plurality of radial bearing surfaces including a first radial bearing surface 110B and a second radial bearing surface 111B. The first radial bearing surface 110B and the second radial bearing surface 111B each extend in an annular shape in the circumferential direction around the rotating shaft 9B, and are separated from each other in the axial direction. The first radial bearing surface 110B is located on the input side in the axial direction and on the outer side in the radial direction than the second radial bearing surface 111B. The carrier bearing 60B is in contact with the outer peripheral surface of the carrier 50B at the first radial bearing surface 110B and the second radial bearing surface 111B, and rotatably supports the carrier 50B. The plurality of radial bearing surfaces may be composed of three or more radial bearing surfaces.

A space 120B is formed between the first radial bearing surface 110B and the second radial bearing surface 111B. The space 120B plays a role of storing grease to be described later, thereby suppressing leakage of grease from the output shaft 90B side. Further, since the carrier 50B is supported by the first radial bearing surface 110B and the second radial bearing surface 111B that are axially separated from each other, the carrier 50B can be prevented from rotating in an inclined state.

The inner peripheral surface of the carrier bearing 60B has an annular bearing step surface 600B that extends perpendicularly or obliquely to the axial direction. In addition, the outer peripheral surface of the carrier 50B has an annular carrier step surface 500B that extends perpendicularly or obliquely to the axial direction. The bearing step surface 600B and the carrier step surface 500B are opposed in the axial direction at least in part. The above-described space 120B is parallel to the bearing step surface 600B, the carrier step surface 500B, the annular surface extending in parallel to the axial direction on the inner peripheral surface of the carrier bearing 60B, and the axial direction on the outer peripheral surface of the carrier 50B. Formed by an expanding annular surface.

Furthermore, the first radial bearing surface 110B is positioned at least on the input side in the axial direction from the bearing step surface 600B and the carrier step surface 500B, and the second radial bearing surface 111B is formed from at least the bearing step surface 600B and the carrier step surface 500B. Is also located on the axial output side. That is, the first radial bearing surface 110B and the second radial bearing surface 111B are located on the outer side in the axial direction from the bearing step surface 600B and the carrier step surface 500B. Thereby, the space 120B can be easily formed without excessively complicating the structures of the carrier 50B and the carrier bearing 60B. However, the positional relationship in the axial direction between the first radial bearing surface 110B and the second radial bearing surface 111B may be reversed.

It is desirable that a first grease is sealed as a lubricant between the plurality of planetary rollers 30B and at least one of the sun roller (not shown) and the internal ring 40B. In this case, it is desirable that a second grease having a viscosity higher than that of the first grease is enclosed in the space 120B (not shown). Thereby, it is possible to prevent the first grease in the traction reduction gear 1B from flowing and leaking to the output shaft 90B side by the second grease. Note that the space 120B may be a space formed between at least two of the plurality of radial bearing surfaces, and is between the radial bearing surfaces different from the first radial bearing surface 110B and the second radial bearing surface 111B. It may be a space formed.

The exemplary embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments.

In the above embodiment, the reduction gear with motor and the traction reduction gear were used for precision parts of electrical appliances. However, the traction reduction gear and the reduction gear with electric motor of the present invention may be used for other applications such as industrial machinery.

In the above embodiment, three planetary rollers are arranged at equal intervals in the circumferential direction around the sun roller. However, the number of planetary rollers included in the traction reducer may be two or four or more.

In the above embodiment, the elastic member is an annular member that expands and contracts in the axial direction. However, the elastic member only needs to generate a repulsive force in the axial direction. For example, a plurality of coil springs may be arranged at equal intervals in the circumferential direction, and may be constituted by other members. It may be.

In the second embodiment, three carrier poles are arranged at equal intervals in the circumferential direction around the sun roller and between the planetary rollers. However, the number of carrier poles may be two or four or more.

For example, a high-strength metal may be used as the material of each member constituting the wheel-in speed reducer. However, the material of each member is not limited to metal as long as it can withstand the load during use. In order to reduce the weight, a resin may be used as the material of some members.

Further, the shape of the details of the traction reducer and the reduction gear with an electric motor may be different from the shapes shown in the drawings of the present application. Moreover, you may combine suitably each element which appeared in said embodiment and modification in the range which does not produce inconsistency.

The present invention can be used for a traction speed reducer and a speed reducer with an electric motor.

1, 1A,

1B Traction reducer

9, 9A,

9B Rotating shaft

10, 10A, 10B Motor-equipped

reducer

11,

11A Motor

12,

12A Mounting plate

20,

20A Sun rollers

30, 30A,

30B Planetary rollers

31,

31A Disc Portions

32,

32A Shaft portions

33, 33A Inclined surfaces 40, 40A, 40B Internal rings 41, 41A Fixed

internal rings

42, 42A Movable

internal rings

43, 43A

First detent portions

50, 50A,

50B Carriers

511A, 512A First carrier member 52A Second carrier member

53A Carrier pole

54, 54A Contact surface 55 Recess 55A Through hole 56

Housing portion

60, 60A, 60B Carrier bearing 70,

70A Elastic member

80, 80A Housing 81

Claw portion

82, 82A Second rotation Stop

part

90, 90A, 90B Output shaft 110B First radial bearing surface 111B Second radial bearing surface 120B Space 500B Carrier step surface 600B Bearing step surface

Claims

A traction reducer,
A sun roller that rotates about a rotation axis;
A plurality of planetary rollers disposed around the sun roller;
A pair of annular internal rings in contact with the plurality of planetary rollers;
A carrier that rotates about the rotation axis while holding the planetary roller;
Have
Each of the plurality of planetary rollers revolves around the rotation axis while rotating by receiving power from the sun roller while contacting both the sun roller and the internal ring.
The carrier has a contact surface facing the outer peripheral surface of the planetary roller;
The outer peripheral surface of the planetary roller and the contact surface are in contact with each other in the circumferential direction about the rotation axis.
The traction reducer according to claim 1,
The planetary roller is
A disk portion in contact with the sun roller;
A shaft portion extending from the center of the disc portion to both sides in the axial direction;
Have
The contact surface of the carrier is in contact with the outer peripheral surface of the shaft portion in the circumferential direction.
The traction reducer according to claim 2,
The shaft portion has an annular inclined surface inclined with respect to the axial direction at an end opposite to the disk portion in the axial direction,
The internal ring contacts the inclined surface.
The traction reducer according to claim 2 or claim 3,
The carrier is arranged in a circumferential direction centering on the rotation axis, and each of the carriers has a plurality of accommodating portions that are opened outward in the radial direction.
The shaft portion is housed in the housing portion.
The traction reducer according to claim 2,
It further has an elastic member that expands and contracts in the axial direction,
The shaft portion has an annular inclined surface inclined with respect to the axial direction,
The pair of internal rings is:
A fixed internal ring that is positioned on one side in the axial direction from the disk portion and in which the position in the axial direction is fixed;
A movable internal ring that is located on the other side in the axial direction than the disc part and is movable in the axial direction;
Have
The elastic member presses the movable internal ring in one axial direction,
The pair of internal rings pressurize the planetary roller radially inward.
The traction reducer according to claim 5,
The elastic member is located on the radially outer side of the carrier.
The traction reducer according to any one of claims 1 to 6,
The sun roller receives power from the axial input side,
It further has an output shaft fixed to the carrier and extending to the output side opposite to the input side in the axial direction along the rotation axis.
The traction reducer according to any one of claims 1 to 7,
A carrier bearing rotatably supporting the carrier;
The carrier bearing contacts the outer peripheral surface and the axial end surface of the carrier.
The traction reducer according to claim 8,
The carrier bearing is
A plurality of radial bearing surfaces, each axially spaced apart, each having an annular shape,
The carrier bearing is in contact with the outer peripheral surface of the carrier at the plurality of radial bearing surfaces.
The traction reducer according to claim 9,
The carrier bearing has an annular bearing step surface that extends perpendicularly or obliquely to the axial direction,
The carrier has an annular carrier step surface extending perpendicularly or obliquely to the axial direction,
The bearing step surface and the carrier step surface are at least partially opposed in the axial direction,
The plurality of radial bearing surfaces are positioned at least on one axial side of the bearing step surface and the carrier step surface and on the other axial side of the bearing step surface and the carrier step surface.
A traction reducer according to claim 9 or claim 10, wherein
A first grease between the plurality of planetary rollers and at least one of the sun roller and the internal ring;
A second grease is provided in a space formed between at least two of the plurality of radial bearing surfaces;
The viscosity of the second grease is higher than the viscosity of the first grease.
The traction reducer according to claim 8,
A housing having a cylindrical inner peripheral surface surrounding the internal ring;
The housing has a claw portion extending radially inward,
The claw portion is in axial contact with the carrier bearing.
The traction reducer according to claim 12,
The claw portion and the carrier bearing are in contact with each other in the circumferential direction around the rotation axis.
The traction reducer according to any one of claims 1 to 8,
A housing having a cylindrical inner peripheral surface surrounding the internal ring;
The internal ring has a first non-circular first detent on a part of the outer peripheral surface;
The housing has a non-circular second detent on a part of the inner peripheral surface,
The first detent portion and the second detent portion come into contact with each other.
The traction reducer according to claim 14,
The internal ring has a plurality of the first detent portions arranged at equal intervals in the circumferential direction around the rotation axis,
The housing has a plurality of the second detent portions arranged at equal intervals in the circumferential direction around the rotation shaft.
A traction reducer according to any one of claims 1 to 15,
The carrier is a single member.
A traction reducer according to any one of claims 1 to 15,
The carrier is
A disc-shaped first carrier member having the contact surface;
A second carrier member disposed at an axial position different from the first carrier member;
A carrier pole extending in the axial direction;
Have
One end of the carrier pole in the axial direction is fixed to the first carrier member,
The other end of the carrier pole in the axial direction is fixed to the second carrier member.
A traction reducer according to any one of claims 1 to 17,
An electric motor that rotates the sun roller around the rotation axis;
A reduction gear with an electric motor.