JP2023065233A - Differential device with disconnection mechanism - Google Patents

Abstract

To provide a structure which can easily switch the adaptability of torque transmission between drive wheels and a power transmission mechanism.SOLUTION: One drive shaft 5a out of a pair of drive shafts 5a, 5b is constituted by combining a first shaft 28 which is connected and fixed to a side gear 9a and a second shaft 29 for supporting drive wheels 6 via a reverse input block clutch 30. When a rotation number of the first shaft 28 is larger than a prescribed value, the reverse input block clutch 30 integrally rotates the first shaft 28 and the second shaft 29, and when the rotation number of the first shaft 28 is equal to or smaller than the prescribed value, the reverse input block clutch makes the first shaft 28 and the second shaft 29 idle with respect to each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a differential for distributing power from a drive source to a pair of drive wheels.

In an automotive drive system, the torque of a drive source such as an engine or a drive motor is transmitted to a differential gear via a speed reduction mechanism including a transmission or a power transmission mechanism such as a propeller shaft. , distributed to a pair of drive wheels.

JP 2020-46065 A JP 2020-8124 A

The automotive drive system as described above has room for improvement in terms of improving fuel efficiency or power efficiency. That is, if the accelerator is turned off while the vehicle equipped with the automotive drive device is running, and the vehicle tries to coast, loss occurs at the meshing portion of the speed reduction mechanism, the drive source, etc., and the running distance due to coasting is shortened. It may get lost.

Japanese Patent Laying-Open No. 2020-46065 (Patent Document 1) describes a differential device including a clutch device (disconnection/engagement portion) between a differential case and a side gear. According to such a differential, by disengaging the clutch device and disconnecting the drive wheels from the power transmission mechanism during inertia, the traveling distance during inertia can be increased. As a result, it is possible to improve the fuel consumption performance or the electricity consumption performance of the vehicle.

However, the differential gear disclosed in JP-A-2020-46065 has the following problems.

That is, in the differential device disclosed in Japanese Patent Application Laid-Open No. 2020-46065, as the clutch device, concave portions and convex portions are arranged alternately in the circumferential direction on a pair of axial side surfaces facing each other. A meshing clutch (dog clutch) is used, which is provided with concave and convex portions and is connected by engaging (meshing) the engaging concave and convex portions with each other.

Therefore, when the clutch device is to be engaged in a state in which the relative rotational speed between the differential case and the side gear is higher than a predetermined speed, the protrusions forming one of the engagement unevenness portions will be displaced from the other engagement unevenness portion. is repelled by the convex portion forming the , and the engagement with the concave portion of the other engaging concave-convex portion is hindered.

On the other hand, in a state in which the rotation speed of the differential case and the rotation speed of the side gear completely match, when the engagement uneven portions are brought closer to each other so as to connect the clutch device, one engagement uneven portion is formed. The tip end face of the convex portion on the other side and the tip end face of the projection forming the other engaging concave and convex portion may come into contact with each other. In this case, there is a possibility that the engagement uneven portions cannot be engaged with each other and the clutch device cannot be connected.

Therefore, in the differential device described in JP-A-2020-46065, it is necessary to engage the clutch device in a state where the relative rotational speed between the differential case and the side gear is equal to or lower than a predetermined speed. In short, it is necessary to strictly adjust the timing of connecting the clutch device, which may make the control troublesome.

As a technology related to the present invention, Japanese Patent Application Laid-Open No. 2020-8124 (Patent Document 2) describes a free type reverse input cutoff clutch. In the reverse input cut-off clutch disclosed in Japanese Patent Laid-Open No. 2020-8124, the rotation of the input member and the force applied by the force applying member control the radial movement of the engager, and the rotational torque is transmitted from the input member to the output member. It is possible to switch between a locked state in which it is possible and a free state in which the rotational torque reversely input to the output member is interrupted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and provides a differential gear with a disconnect mechanism that can easily switch between the propriety of torque transmission between the drive wheels and the power transmission mechanism. It is intended to

A differential with a disconnect mechanism according to one aspect of the present invention includes a differential case, at least one pinion gear, a pair of side gears, and a pair of drive shafts.
The differential case has a torque input portion. The torque input portion can be configured by a ring gear that meshes with a gear, a pulley for running a belt, a sprocket for running a chain, or the like.
The pinion gear is supported by the differential case so as to be rotatable about an axis perpendicular to the central axis of the differential case.
The pair of side gears are supported coaxially with the central axis of the differential case so as to be rotatable relative to the differential case, and mesh with the pinion gear.
The pair of drive shafts have their base end portions coupled and fixed to the pair of side gears.

In particular, in the differential with a disconnect mechanism according to one aspect of the present invention, one drive shaft of the pair of drive shafts has a first shaft, a second shaft, and a reverse input cutoff clutch.
The first shaft has a base end that is coupled and fixed to one side gear of the pair of side gears.
The second shaft is arranged coaxially with the first shaft.
The reverse input cut-off clutch integrally rotates the first shaft and the second shaft when the number of rotations (rotational speed) of the first shaft is greater than a predetermined value (rotational speed). On the other hand, when the number of revolutions of the first shaft is equal to or less than the predetermined value (including a state in which the first shaft is not rotating), the first shaft and the second shaft are mutually connected. let it idle.

In the differential gear with disconnect mechanism according to one aspect of the present invention, the reverse input cut-off clutch may include an output portion, an input portion, an engaging element, and a force applying member.
The output portion has a surface to be pressed on its inner peripheral surface, and rotates integrally with the second shaft.
The input portion has a cam portion arranged radially inward of the surface to be pressed, and rotates integrally with the first shaft.
The engaging element has a pressing surface facing the pressed surface, and is disposed between the pressed surface and the cam portion in the radial direction.
The force applying member applies a force to the engaging element in a direction in which the pressing surface separates from the pressed surface.
In the reverse input cut-off clutch, the force in the direction of bringing the pressing surface acting on the engaging element closer to the pressed surface with the rotation of the input portion and the rotation of the engaging element is generated by the force applying member. When the force applied to the engaging element is larger than the force applied to the engaging element, the engaging element moves radially in a direction in which the pressing surface approaches the pressed surface, thereby frictionally engaging the pressing surface with the pressed surface. , the input portion and the output portion are rotated integrally, but the input portion is not rotated, or the engagement element rotates with the rotation of the input portion and the rotation of the engagement element. is less than or equal to the force applied to the engaging member by the force applying member, the force applied to the engaging member by the force applying member By forming a gap between the pressed surface and the pressing surface based on the above, the input section and the output section are idly rotated relative to each other.

It should be noted that the force acting on the engaging element in the direction of bringing the pressing surface closer to the pressed surface along with the input of rotational torque to the input portion is determined based on the engagement of the engaging element with the cam portion. It is a resultant force of a force that tends to radially move the surface in a direction to bring it closer to the pressed surface and a centrifugal force that acts on the engaging element.

In the differential gear with a disconnection mechanism according to one aspect of the present invention, the engaging element may have a pair of pressing surfaces that are circumferentially spaced apart from each other.

In the differential gear with a disconnect mechanism according to one aspect of the present invention, the input section may have an input side guide section, and the engaging element may have an engaging element side guide section. In this case, in a state where the gap is formed between the pressed surface and the pressing surface based on the force applied to the engaging element by the force applying member, the input section side guide section and the engaging element The side guide portion engages without backlash in a first direction, which is a far-near direction of the pressing surface with respect to the pressed surface, and in a second direction, which is perpendicular to the central axis of the input portion.

A differential gear with a disconnect mechanism according to an aspect of the present invention may include a pair of the engaging elements so as to sandwich the cam portion from the radially outer side.
In this case, the force applying member can be provided so as to span between the pair of engaging elements.

In the differential gear with a disconnection mechanism according to one aspect of the present invention, the force applying member can be configured by an elastic member such as a spring or rubber.

In the differential gear with a disconnect mechanism according to one aspect of the present invention, the minimum value of the circumscribed circle diameter of the cam portion is larger than the outer diameter of the portion of the first shaft that is coupled and fixed to the one side gear. You can make it bigger.
Alternatively, the minimum value of the diameter of the circumscribed circle of the cam portion may be less than or equal to the outer diameter of the portion of the first shaft that is coupled and fixed to the one side gear.

According to the differential gear of one aspect of the present invention, it is possible to easily switch between the propriety of torque transmission between the driving wheels and the power transmission mechanism.

FIG. 1 is a schematic diagram showing an example of an electric vehicle drive device incorporating a differential gear according to an example of the embodiment. FIG. 2 is a cross-sectional view showing a differential gear according to one example of the embodiment. FIG. 3 is an exploded perspective view showing a reverse input cut-off clutch extracted from a differential gear according to one example of the embodiment. FIG. 4 is a partially omitted perspective view of a reverse input cutoff clutch. FIG. 5 is a diagram corresponding to the XX cross section of FIG. 2, showing the reverse input cut-off clutch with some parts omitted. FIG. 6 is a view similar to FIG. 5 showing the reverse input disconnect clutch with the vehicle not coasting; FIG. 7 is a view similar to FIG. 5 showing the reverse input disconnect clutch with the vehicle coasting at high speed; FIG. 8 is a view similar to FIG. 5 showing the reverse input disconnect clutch with the vehicle coasting at low speed; 9A is an enlarged view of the central portion of FIG. 6, FIG. 9B is an enlarged view of the central portion of FIG. 7, and FIG. 9C is an enlarged view of the central portion of FIG. . FIG. 10 is a perspective view showing the input portion taken out from the reverse input cut-off clutch and omitting the small-diameter shaft portion.

An example of an embodiment of the present invention will be described with reference to FIGS. 1 to 10. FIG. FIG. 1 shows an electric vehicle driving device 2 incorporating a differential device 1 of this embodiment. In the electric vehicle driving device 2, the output torque of the drive motor 3 is increased by the power transmission mechanism 4, transmitted to the differential device 1, and distributed to the pair of drive shafts 5a and 5b by the differential device 1. . As a result, the drive wheels 6 supported via suspensions (not shown) are driven to rotate at the tips of the pair of drive shafts 5a and 5b.

In this example, the power transmission mechanism 4 is configured by a gear-type speed reducer. The power transmission mechanism 4 includes a drive gear 4a, an intermediate shaft 4b, an intermediate gear 4c, and a final reduction gear (final gear) 4d. The drive gear 4 a is supported and fixed to the output shaft 3 a of the drive motor 3 . The intermediate shaft 4b is parallel to the output shaft 3a of the drive motor 3 and rotatably supported on a vehicle body (not shown). The intermediate gear 4c has more teeth than the drive gear 4a, and is supported and fixed to the intermediate shaft 4b. The final reduction gear 4d has fewer teeth than the intermediate gear 4c, and is supported and fixed to the intermediate shaft 4b.

The power transmission mechanism 4 is an automatic transmission (AT), a belt type or toroidal type continuously variable transmission (CVT), an automated manual transmission (AMT), a dual clutch transmission (DCT), or a manual transmission (MT). It is also possible to provide a transmission such as a transmission and a propeller shaft. In addition, the power transmission mechanism 4 is replaced with a gear-type speed reducer, or in addition to a gear-type speed reducer, for example, by a belt-type or chain-type power transmission mechanism and/or a friction roller speed reducer. Can also be configured.

The differential gear 1 of this example includes a differential case 7, a pinion gear 8, a pair of side gears 9a and 9b, and a pair of drive shafts 5a and 5b.

Regarding the differential gear 1, the axial direction, the circumferential direction and the radial direction refer to the axial direction, the circumferential direction and the radial direction of the differential case 7 unless otherwise specified. Further, the axial direction, circumferential direction and radial direction of the differential case 7 coincide with the axial direction, circumferential direction and radial direction of the pair of side gears 9a and 9b, and the axial direction and circumferential direction of the pair of drive shafts 5a and 5b. Consistent with direction and radial direction. Further, one side in the axial direction means the right side in FIGS. 1 and 2, and the other side in the axial direction means the left side in FIGS.

The differential case 7 has a ring gear 10 forming a torque input portion. The ring gear 10 is a helical gear and meshes with the final reduction gear 4 d of the power transmission mechanism 4 . In this example, the differential case 7 includes a stepped cylindrical case member 11 and a gear member 12 .

The case member 11 includes a small diameter tubular portion 13a, a connecting portion 14a, a large diameter tubular portion 15, a connecting portion 14b, and a small diameter tubular portion 13b in order from one side in the axial direction.

The small-diameter tubular portion 13a has a cylindrical shape.

The connecting portion 14a has a substantially hollow circular plate shape, and connects the other axial end of the small-diameter tubular portion 13a on one axial side and the one axial end of the large-diameter tubular portion 15 . That is, the radially inner end of the connecting portion 14a is connected to the other axial end of the small-diameter cylindrical portion 13a, and the radially outer end of the connecting portion 14a is connected to the large-diameter cylindrical portion 15. It is connected to one end in the axial direction.

The large-diameter cylindrical portion 15 has a substantially cylindrical shape. The large-diameter cylindrical portion 15 has circular holes 16 that are open to the inner peripheral surface at least one position in the circumferential direction (in the illustrated example, two positions on the opposite side in the radial direction), It has a hollow circular plate-like outward flange portion 17 that protrudes outward. A base end portion of a support shaft 18 for supporting a pinion gear 8 to be described later is fitted and fixed in each of the circular holes 16 . In addition, the large-diameter cylindrical portion 15 has opening windows at at least one position in the circumferential direction (for example, two positions on the opposite side in the radial direction). When assembling the differential gear 1, the pinion gear 8 and the side gears 9a and 9b are arranged inside the large-diameter cylindrical portion 15 through the opening window.

The connecting portion 14b has a substantially hollow circular plate shape, and connects the other axial end portion of the large-diameter cylindrical portion 15 and the one axial end portion of the small-diameter cylindrical portion 13b on the other axial side. . That is, the radially outer end of the connecting portion 14b is connected to the other axial end of the large-diameter cylindrical portion 15, and the radially inner end of the connecting portion 14b is connected to the small-diameter cylindrical portion 13b. It is connected to one end in the axial direction.

The small-diameter tubular portion 13b has a cylindrical shape.

The case member 11 is rotatably supported by a pair of tapered roller bearings 19a and 19b having a face-to-face (DF) contact angle with respect to a fixed portion 20 that does not rotate during use. Specifically, the tapered roller bearing 19a on one axial side is arranged between the outer peripheral surface of the small-diameter tubular portion 13a on one axial side and the inner peripheral surface of the fixed portion 20, and the small-diameter tubular portion on the other axial side is arranged. Between the outer peripheral surface of the portion 13b and the inner peripheral surface of the fixed portion 20, a tapered roller bearing 19b on the other side in the axial direction is arranged. Thereby, the case member 11 is rotatably supported inside the fixed portion 20 .

The gear member 12 includes a cylindrical portion 21 having the ring gear 10 on its outer peripheral surface, and a hollow circular plate-shaped inward flange portion 22 protruding radially inward from an axially intermediate portion of the cylindrical portion 21 .

Case member 11 and gear member 12 are coupled and fixed by a plurality of bolts 23 . That is, each bolt 23 is inserted through a through hole provided in the inward flange portion 22 of the gear member 12 and screwed into a threaded hole provided in the outward flange portion 17 of the case member 11, whereby the case is The member 11 and the gear member 12 are coupled and fixed to form the differential case 7.

The pinion gear 8 is supported on the differential case 7 so as to be rotatable about an axis perpendicular to the central axis _O7 of the differential case 7 . In this example, one pair of pinion gears 8 are provided, and each pinion gear 8 is configured by a bevel gear. That is, the pinion gear 8 has a substantially truncated cone shape and has a plurality of teeth on the outer peripheral surface. Furthermore, the pinion gear 8 has a central hole 24 that penetrates the pinion gear 8 in its axial direction. The pinion gear 8 is rotatably supported via a radial bearing 25 around the tip of a support shaft 18 fitted and fixed to the large-diameter cylindrical portion 15 of the differential case 7 .

A pair of side gears 9 a and 9 b are supported coaxially with the central axis O ₇ of the differential case 7 so as to be rotatable relative to the differential case 7 and mesh with the pinion gear 8 . Each of the side gears 9a, 9b is composed of a bevel gear. That is, the side gears 9a and 9b have a substantially truncated cone shape, and have a plurality of teeth meshing with the teeth of the pinion gear 8 on the outer peripheral surface. Furthermore, the side gears 9a and 9b have a spline hole 26 extending axially through the central portion thereof. The side gears 9a, 9b are arranged inside the large-diameter tubular portion 15 of the differential case 7, and are coupled and fixed to the base ends of the drive shafts 5a, 5b so as to transmit torque. That is, the male spline portion 27 provided on the outer peripheral surface of the base end portion of the drive shafts 5 a and 5 b is spline-engaged with the female spline portion provided on the inner peripheral surface of the spline hole 26 .

Of the pair of drive shafts 5 a and 5 b, the drive shaft 5 a on one side in the axial direction has a first shaft 28 , a second shaft 29 and a reverse input cutoff clutch 30 .

The first shaft 28 has its base end (end on the other side in the axial direction) coupled and fixed to the side gear 9a on one side in the axial direction of the pair of side gears 9a and 9b. That is, the first shaft 28 has the male spline portion 27 on the outer peripheral surface of the base end portion.

The second shaft 29 is supported coaxially with the first shaft 28 and rotatable relative to the first shaft 28 . The drive wheel 6 is supported at the tip of the second shaft 29 (one end in the axial direction) via a suspension.

The reverse input cutoff clutch 30 is a free type (idling type) reverse input cutoff clutch. That is, when the number of rotations (rotational speed) of the first shaft 28 is greater than a predetermined value (faster than the predetermined rotational speed), the reverse input cutoff clutch 30 separates the first shaft 28 and the second shaft 29 from each other. and are rotated integrally, when the rotation speed of the first shaft 28 is equal to or less than a predetermined value (below a predetermined rotation speed), the first shaft 28 and the second shaft 29 are rotated. idling each other. In this example, the reverse input blocking clutch 30 includes a housing 31 , an output portion 32 , an input portion 33 , a pair of engaging elements 34 and a pair of force applying members 35 .

The housing 31 is configured in a stepped cylindrical shape. In this example, the housing 31 includes a hollow circular plate-shaped side plate portion 36, a large-diameter cylindrical portion 37 protruding from the radially outer portion of the side plate portion 36 toward one side in the axial direction along the entire circumference, and the side plate portion 36. and a small-diameter cylindrical portion 38 that is bent along the entire circumference from the radially inner end portion of the cylindrical portion 38 toward the other side in the axial direction. Further, the housing 31 has an inward flange portion 39 that is bent radially inward along the entire circumference from the end portion on the other axial side of the small-diameter tubular portion 38 , and the large-diameter tubular portion of the side plate portion 36 . A plurality of through-holes 40 extending axially are provided at a plurality of locations in the circumferential direction of a portion protruding radially outward from the outer peripheral surface of 37 .

The housing 31 is supported and fixed to the fixed portion 20 by screwing a bolt 41 inserted through the through hole 40 into a screw hole 77 opening in one axial side of the fixed portion 20 which does not rotate during use and further tightening. be done.

The output portion 32 has an output shaft portion 42 , a cylindrical portion 43 and a side plate portion 44 . In this example, the output portion 32 is provided integrally with the base end portion of the second shaft 29 (end portion on the other side in the axial direction). Alternatively, when carrying out the present invention, the second shaft can also be configured by integrally rotatably coupling and fixing a shaft body having a distal end connected to a suspension and an output section.

The output shaft portion 42 has a columnar small diameter portion 45 arranged on one side in the axial direction and a cylindrical large diameter portion 46 arranged on the other side in the axial direction. The output shaft portion 42 is provided integrally with the base end portion of the second shaft 29 . The large-diameter portion 46 is a stepped cylindrical inner surface formed by connecting a small-diameter cylindrical surface portion 47 on one side in the axial direction and a large-diameter cylindrical surface portion 48 on the other side in the axial direction through a stepped portion 49 facing the other side in the axial direction. has a peripheral surface.

The cylindrical portion 43 has a pressed surface 50 which is a cylindrical concave surface on its inner peripheral surface, and is arranged on the other side of the output shaft portion 42 in the axial direction.

The side plate portion 44 is configured in the shape of a hollow circular plate, and connects the other end portion in the axial direction of the output shaft portion 42 (the large diameter portion 46 ) and the one side portion of the cylindrical portion 43 in the axial direction.

In the reverse input cut-off clutch 30 of this example, the cylindrical portion 43 of the output portion 32 is rotatably supported radially inward of the large-diameter cylindrical portion 37 of the housing 31 via a radial needle bearing 51 . That is, an outer ring 52 formed by bending a metal plate into a substantially U-shaped cross section is fitted in the large-diameter cylindrical portion 37 by an interference fit, and between the inner peripheral surface of the outer ring 52 and the outer peripheral surface of the cylindrical portion 43, A radial needle bearing 51 is configured by arranging a plurality of needles 54 held by a retainer 53 so as to be able to roll. Thereby, the output section 32 is rotatably supported with respect to the housing 31 .

In this example, the opening on one side in the axial direction of the cylindrical space that exists between the inner peripheral surface of the large-diameter cylindrical portion 37 and the outer peripheral surface of the cylindrical portion 43 and in which the radial needle bearing 51 is installed is It is closed by a sealing member 55 . This prevents the grease sealed in the cylindrical space from leaking to the external space, and foreign matter such as moisture from entering the cylindrical space.

The input portion 33 has a large-diameter shaft portion 56, a cam portion 57, and a small-diameter shaft portion 58 in order from the other side in the axial direction. The large-diameter shaft portion 56, the cam portion 57, and the small-diameter shaft portion 58 are all arranged coaxially and in series. Note that, in this example, the input portion 33 is provided integrally with the tip portion (the end portion on one side in the axial direction) of the first shaft 28 . However, when carrying out the present invention, the first shaft can also be configured by integrally rotatably coupling and fixing a shaft body having a male spline portion on the outer peripheral surface of the base end portion and an input portion.

The large-diameter shaft portion 56 has a columnar shape and is integrally provided at the distal end portion of the first shaft 28 . The large-diameter shaft portion 56 has an outward flange portion 59 protruding radially outward at one end in the axial direction.

The cam portion 57 has a substantially rectangular end surface shape including four arc-shaped or elliptical arc-shaped corners when viewed from the axial direction. That is, the outer peripheral surface of the cam portion 57 includes a pair of first flat surface portions 60 arranged on both sides in the short axis direction (up and down direction in FIG. 5), and a pair of first flat surface portions 60 arranged on both sides in the long axis direction (left and right direction in FIG. 5). Consists of a pair of second flat surface portions 61 and a connecting surface portion 62 having an arc or elliptical arc cross section connecting the long axis direction end portion of the first flat surface portion 60 and the short axis direction end portion of the second flat surface portion 61. It is Therefore, the distance from the central axis (the center of rotation of the cam portion 57) O33 of the input portion ₃₃ to the outer peripheral surface of the cam portion 57 changes in the circumferential direction. Further, the width dimension of the cam portion 57 in the major axis direction becomes smaller toward the end portion in the minor axis direction. Note that the first flat surface portion 60 and the connection surface portion 62 smoothly connect the ends of each other in the tangential direction.

The small-diameter shaft portion 58 is configured in a cylindrical shape.

The input portion 33 rotatably supports the large-diameter shaft portion 56 radially inward of the small-diameter cylindrical portion 38 of the housing 31 via a radial rolling bearing 63a. It is rotatably supported inside the large diameter portion 46 in the radial direction via a radial rolling bearing 63b. In this state, the cam portion 57 is arranged radially inside the pressed surface 50 .

That is, the radial rolling bearing 63a on the other side in the axial direction includes an outer ring fitted inside the small-diameter cylindrical portion 38, an inner ring fitted onto the large-diameter shaft portion 56, and an inner peripheral surface of the outer ring and an outer peripheral surface of the inner ring. and a plurality of rolling elements rotatably arranged therebetween. The outer ring is sandwiched from both sides in the axial direction between one axial side surface of the inward flange portion 39 and a snap ring 67a engaged with the inner peripheral surface of one axial end portion of the small-diameter tubular portion 38 . The inner ring is sandwiched from both sides in the axial direction between the other axial side surface of the outward flange portion 59 and a retaining ring 67b engaged with the outer peripheral surface of the axially intermediate portion of the large-diameter shaft portion 56 .

The radial rolling bearing 63b on one side in the axial direction includes an outer ring fitted inside the large-diameter cylindrical surface portion 48 provided on the inner peripheral surface of the large-diameter portion 46, an inner ring fitted onto the small-diameter shaft portion 58, and an outer ring. and a plurality of rolling elements arranged to be free to roll between the inner peripheral surface of the inner ring and the outer peripheral surface of the inner ring. The outer ring is sandwiched from both sides in the axial direction between the stepped portion 49 and a retaining ring 67c that is engaged with the end portion of the large-diameter cylindrical surface portion 48 on the other axial side. The inner ring is sandwiched from both sides in the axial direction between an end face of the cam portion 57 on one side in the axial direction and a retaining ring 67d engaged with the outer peripheral face of the end portion on the one side in the axial direction of the small-diameter shaft portion 58 .

In this example, the radial rolling bearings 63a and 63b are configured by radial ball bearings using balls as rolling elements. However, the radial rolling bearings 63a and 63b can also be composed of radial tapered roller bearings using tapered rollers as rolling elements or radial roller bearings using cylindrical rollers (including needles).

The pair of engaging elements 34 has a substantially semicircular (substantially arcuate) end surface shape when viewed from the axial direction. The pair of engaging elements 34 are arranged between the pressed surface 50 of the output portion 32 and the cam portion 57 of the input portion 33 so as to sandwich the cam portion 57 from both sides of the cam portion 57 in the minor axis direction. there is The pair of engaging elements 34 are the same parts that are made to have the same shape and size.

The pair of engaging elements 34 have their radially outer surfaces corresponding to arcs oriented opposite to each other and their radially inner surfaces corresponding to chords facing each other. It is arranged so as to be movable in a first direction (the direction indicated by α in FIG. 5 ), which is the direction in which it is moved farther and nearer with respect to 50 . That is, in a state in which the pair of engaging elements 34 are arranged between the pressed surface 50 and the cam portion 57 , each engaging element 34 has its radial outer surface facing the pressed surface 50 in the first direction. The inner diameter of the pressed surface 50 and the radial dimension of the engaging element 34 are restricted so as to be movable.

The pair of engaging elements 34 has a pair of pressing surfaces 68 on their radially outer side surfaces, each of which faces the pressed surface 50 and is spaced apart from each other in the circumferential direction. Each pressing surface 68 is formed of a partially cylindrical convex curved surface having a radius of curvature smaller than the radius of curvature of the pressed surface 50 . It should be noted that, among the radial outer surfaces of the pair of engaging elements 34, the portions that are circumferentially deviated from the pair of pressing surfaces 68 are centered on the central axis O33 of the input portion ₃₃ when viewed in the axial direction. , and exists radially inward of the imaginary circle in contact with the pair of pressing surfaces 68 . That is, in a state in which the pair of pressing surfaces 68 are in contact with the pressed surface 50, the portions of the radial outer side surfaces of the pair of engaging elements 34 that are out of the pair of pressing surfaces 68 in the circumferential direction are: It does not come into contact with the pressed surface 50 .

It is preferable that each pressing surface 68 has a surface texture that has a larger coefficient of friction with respect to the pressed surface 50 than other portions of the engaging element 34 . Further, each pressing surface 68 can be configured integrally with the other portion of the engaging element 34, or formed on the surface of a friction material fixed to the other portion of the engaging element 34 by sticking, bonding, or the like. You can also

Further, the pair of engaging elements 34 are arranged in the central portion of the radially inner side surface in the second direction (the direction indicated by β in FIG. 5) orthogonal to the first direction and the central axis O ₃₂ of the output portion 32. It has a substantially trapezoidal engaging recess 69 .

The engaging concave portion 69 engages with the short-axis direction end portion of the cam portion 57 of the input portion 33 without rattling in the second direction when the reverse input blocking clutch 30 is in the free state, which will be described later. That is, in this example, the short-axis direction end portion of the cam portion 57 constitutes the input portion-side guide portion, and the engaging concave portion 69 constitutes the engaging element-side guide portion. The inner surface of the engaging recess 69 is composed of a bottom surface 70 and a pair of side surface portions 71 .

The bottom surface 70 is configured by a flat surface perpendicular to the first direction. The length dimension of the bottom surface 70 (the length dimension in the second direction) is the same as the length dimension of the first flat surface portion 60 of the cam portion 57, or slightly longer than the length dimension of the first flat surface portion 60. .

The pair of side portions 71 are arranged on both sides of the inner surface of the engaging recess 69 in the second direction and face each other in the second direction. In this example, the pair of side surface portions 71 are concave curved surfaces that are inclined in a direction in which the distance between them widens as they go radially inward of the engaging element 34, that is, as they go away from the pressed surface 50 in the first direction. It is composed of Therefore, the width dimension of the engaging recess 69 in the second direction increases toward the opening side. The pair of side surface portions 71 has a radius of curvature that is the same as the radius of curvature of the connection surface portion 62 of the cam portion 57 or a radius of curvature that is slightly larger than the radius of curvature of the connection surface portion 62 . Note that the bottom surface 70 and the side surface portion 71 smoothly connect their ends in the tangential direction.

Therefore, in the free state of the reverse input cutoff clutch 30 , the bottom surface 70 is in surface contact with the first flat surface portion 60 and the pair of side surface portions 71 are in surface contact with the connecting surface portion 62 .

Further, the pair of engaging elements 34 has semi-elliptical cutouts 72 on both sides of the radially inner side surfaces sandwiching the engaging recess 69 in the second direction. A locking hole 73 extending axially through is provided in a portion located radially outward of the .

The pair of force applying members 35 apply force to the pair of engaging elements 34 in the direction in which the pair of pressing surfaces 68 are separated from the pressed surface 50 . In this example, the pair of force imparting members 35 imparts elasticity to the pair of engaging elements 34 in the direction of approaching each other. For this reason, in this example, the pair of force applying members 35 are configured by extension coil springs. That is, the pair of force applying members 35 includes a coil portion 74 formed by bending a metal wire having elasticity into a helical shape, and a pair of engaging members bent in a substantially L shape from both ends of the coil portion 74 . and a stopping arm portion 75 .

By locking (inserting) the locking arms 75 into the locking holes 73 , each of the force applying members 35 is stretched between the pair of the engaging elements 34 , thereby to give elasticity in the direction of approaching each other. As a result, the cam portion 57 of the input portion 33 is elastically held from both sides in the radial direction by the engaging recesses 69 of the pair of engaging elements 34 . Specifically, the bottom surface 70 is elastically pressed against the first flat surface portion 60 and the side surface portion 71 is elastically pressed against the connection surface portion 62 . Then, in the free state of the reverse input interrupting clutch 30, the posture (rotational phase) of the cam portion 57 is regulated such that the longitudinal direction of the cam portion 57 is substantially parallel to the radial inner side surface of the engaging element 34, A gap 79 is formed between the surface 50 and the pair of pressing surfaces 68 .

Note that when the pair of force applying members 35 are stretched between the pair of engaging elements 34, the lengthwise side portions of the coil portion 74 and the pair of locking arm portions 75 are notched portions. 72 inside.

The reverse input cut-off clutch 30 operates according to the magnitude of the force F in the direction in which the pair of pressing surfaces 68 acting on the engaging element 34 approach the pressed surface 50 as the input portion 33 and the engaging element 34 rotate. , a locked state in which the input portion 33 and the output portion 32 are rotated integrally, and a free state in which the input portion 33 and the output portion 32 are idly rotated.

When rotational torque is input to the input portion 33, as shown in FIG. 6, the cam portion 57 rotates inside the pair of engaging recesses 69 in the rotational direction of the input portion 33 (clockwise in the example of FIG. 6). ). Then, the connecting surface portion 62 of the cam portion 57 presses the bottom surface 70 of the engaging recess 69 . At this time, based on the connecting surface portion 62 pressing the bottom surface 70, a force that causes the pair of engaging elements 34 to move the pair of pressing surfaces 68 radially outward in a direction to bring the pair of pressing surfaces 68 closer to the pressed surface 50; As the pair of engaging elements 34 rotate about the central axis O ₃₃ of the input portion 33, the resultant force F of the centrifugal force acting on the pair of engaging elements 34 is (F>f), the pair of engaging elements 34 move radially outward in a direction to bring the pair of pressing surfaces 68 closer to the pressed surface 50 . Then, the pair of pressing surfaces 68 are pressed against the pressed surface 50 for frictional engagement, and the pair of engaging elements 34 are stretched between the cam portion 57 and the pressed surface 50 . As a result, the reverse input cutoff clutch 30 is switched to a locked state in which the input portion 33 and the output portion 32 are rotated integrally. As a result, the rotational torque input to the input portion 33 is transmitted to the output portion 32 via the pair of engaging elements 34 .

When the resultant force F is greater than the force f applied to the pair of engaging elements 34 by the pair of force applying members 35, the reverse input cut-off clutch 30 operates on the pair of The engaging elements 34 are moved in a direction approaching the pressed surface 50 with respect to the first direction. The input portion 33 and the output portion 32 are integrally rotated via the pair of engaging elements 34 .

On the other hand, the pair of engaging elements 34 bring the pair of pressing surfaces 68 closer to the pressed surface 50 as the input section 33 rotates and the engaging elements 34 rotate, including when the input section 33 is not rotating. direction and the centrifugal force acting on the pair of engaging elements 34 is less than or equal to the force f applied to the engaging elements 34 by the pair of force applying members 35 ( In the case of F≦f), a gap 76 is formed between the pressed surface 50 and the pair of pressing surfaces 68 based on the force f applied to the engaging elements 34 by the pair of force applying members 35 . As a result, the reverse input cutoff clutch 30 is switched to a free state in which the input portion 33 and the output portion 32 are idly rotated.

When the resultant force F is less than or equal to the force f applied to the pair of engaging elements 34 by the pair of force applying members 35, the reverse input interrupting clutch 30 is configured to operate regardless of the rotational direction of the input portion 33 and the output portion 32. The part 33 and the output part 32 are idling each other.

As will be described later, the magnitude of the force (elasticity) applied by the pair of force applying members 35 to the pair of engaging elements 34 varies between the pair of drive wheels 6 and the drive motor 3 after the accelerator is turned off. and the power transmission mechanism 4 are appropriately set according to the running speed of the vehicle (vehicle speed). However, the force applied by the pair of force applying members 35 to the pair of engaging elements 34 is due to the input of rotational torque to the input section 33 based on the output of torque from the drive motor 3 that is sufficient to start the vehicle. Along with this, the pair of pressing surfaces 68 acting on the pair of engaging elements 34 is made smaller than the force in the direction of approaching the pressed surface 50 .

In the vehicle equipped with the electric vehicle driving device 2 of this example, the reverse input cutoff clutch 30 is switched between the locked state and the free state according to the running state.

<When the vehicle is not coasting>
When the accelerator is operated (the accelerator pedal is stepped on) while the shift lever is switched to the driving range (D range or R range), torque is output from the drive motor 3 . Torque output from the drive motor 3 is increased by the power transmission mechanism 4 and then transmitted to the differential case 7 .

When the differential case 7 rotates, the pair of pinion gears 8 rotate (revolve) around the central axis _O7 of the differential case 7, and further, based on the meshing of the teeth of the pinion gear 8 and the teeth of the side gears 9a and 9b, the pair of side gears 9a and 9b rotate about their own central axis coaxial with the central axis O7 of the differential case _7. As shown in FIG.

When the side gear 9a on one side in the axial direction of the pair of side gears 9a and 9b rotates, the first shaft 28 coupled and fixed to the side gear 9a rotates. As the first shaft 28 rotates and the input portion 33 rotates, a force F acting on the engaging element 34 in the direction of bringing the pair of pressing surfaces 68 closer to the pressed surface 50 is applied to the pair of force applying members. 35 becomes larger than the force f applied to the pair of engaging elements 34, the reverse input cutoff clutch 30 switches to the locked state. As a result, the rotational torque transmitted to the first shaft 28 is transmitted to the second shaft 29, and the drive wheel 6 on one side in the axial direction supported by the tip of the second shaft 29 is rotationally driven.

On the other hand, when the side gear 9b on the other side in the axial direction of the pair of side gears 9a and 9b rotates, the drive shaft 5b on the other side in the axial direction coupled and fixed to the side gear 9b is rotationally driven, and the tip of the drive shaft 5b is driven to rotate. A drive wheel 6 on the other side in the axial direction supported by the portion is rotationally driven.

<When the vehicle is coasting at high speed>
Immediately after the accelerator is turned off while the vehicle is running at high speed, the pair of engaging elements 34 move the pair of pressing surfaces 68 to the pressed surface 50 due to the influence of inertia, as shown in FIGS. It rotates around the central axis O ₃₃ of the input portion 33 while being kept in contact with it. As shown in FIG. 7, the bottom surface 70 of the engaging recess 69 is the connection surface portion of the cam portion 57 that presses the bottom surface 70 in the long axis direction when the drive torque is transmitted from the drive motor 3 . The connecting surface portion 62 on the side opposite to 62 is pressed.

On the other hand, after the transmission of the drive torque from the drive motor 3 stops as the accelerator is turned off, the input section 33 receives the regenerative torque accompanying the drive motor 3 operating as a generator, the differential gear 1 and A drag resistance acts based on meshing resistance and the like in the meshing portion of the power transmission mechanism 4 . Therefore, in the pair of engaging elements 34, the pair of pressing surfaces 68 is brought closer to the pressed surface 50 as a reaction force from the cam portion 57 to the bottom surface 70 of the engaging recess 69 pressing the connecting surface portion 62. A directional force is applied. While the resultant force F of this force and the centrifugal force acting on the pair of engaging elements 34 is greater than the force f applied to the pair of engaging elements 34 by the pair of force applying members 35, the reverse input cut-off clutch is maintained. 30 is in a locked state as shown in FIG. 7, and the first shaft 28 rotates integrally with the second shaft 29 through the pair of engaging elements 34 . Therefore, the rotational torque of the first shaft 28 (the drive shaft 5a on one side in the axial direction) and the drive shaft 5b on the other side in the axial direction is transmitted through the side gears 9a and 9b, the pinion gear 8, the differential case 7, and the power transmission mechanism 4. , is transmitted to the output shaft 3 a of the drive motor 3 . Regenerative braking is performed by the drive motor 3 operating as a generator.

It should be noted that the difference in rotational speed between the pair of drive wheels 6 that occurs during cornering or the like during non-inertia running and high-speed inertia running of the vehicle is It is absorbed by rotating (rotating) around the center.

<When the vehicle is coasting at low speed>
When the vehicle speed decreases due to regenerative braking, the centrifugal force acting on the pair of engaging elements 34 and the pair of pressing surfaces 68 applied to the pair of engaging elements 34 from the cam portion 57 are applied to the pressed surface 50. The force that tends to move radially outward in the approaching direction is reduced. As a result, when the resultant force F becomes equal to or less than the force f applied by the pair of force applying members 35 to the pair of engaging elements 34, the reverse input cutoff clutch 30 becomes free as shown in FIG. In this free state, the first shaft 28 and the second shaft 29 idle against each other. In short, the drive wheel 6 on one side in the axial direction is separated from the drive motor 3 and the power transmission mechanism 4 .

On the other hand, the rotation of the drive wheel 6 on the other side in the axial direction is transmitted to the pinion gear 8 via the meshing portion between the side gear 9b on the other side in the axial direction and the pinion gear 8, and the pinion gear 8 rotates about the support shaft 18 ( rotate). The rotation (rotation) of the pinion gear 8 is transmitted to the side gear 9a on one side in the axial direction through the meshing portion between the pinion gear 8 and the side gear 9a on the one side in the axial direction. Then, the first shaft 28 to which the side gear 9a on one side in the axial direction is coupled and fixed rotates idly with respect to the second shaft 29 supporting the driving wheel 6 on one side in the axial direction. As the first shaft 28 idles with respect to the second shaft 29 in this manner, the drive wheel 6 on the other side in the axial direction is allowed to rotate, so the differential case 7 does not rotate. In short, the drive wheel 6 on the other axial side is separated from the drive motor 3 and the power transmission mechanism 4 .

As described above, according to the differential gear 1 of the present embodiment, during coasting at low speed (with the accelerator off and the vehicle running at low speed), the pair of drive wheels 6 and the power The transmission mechanism 4 and the drive motor 3 can be separated. Therefore, it is possible to lengthen the distance traveled by inertia travel. In other words, it is possible to slow down the speed reduction during inertia running. As a result, the power consumption performance of the vehicle (electric vehicle) in which the differential gear 1 is mounted can be improved.

Particularly in this example, one (one side in the axial direction) of the pair of drive shafts 5a and 5b is combined with the first shaft 28 and the second shaft 29 via the reverse input cutoff clutch 30. It consists of Therefore, it is possible to easily switch between the pair of drive wheels 6, the power transmission mechanism 4, and the drive motor 3 to enable or disable torque transmission. The reason for this will be explained below.

In the differential gear 1 of this embodiment, the reverse input cutoff clutch 30 is locked during non-inertia running in which the pair of drive wheels 6 are rotationally driven by operating the accelerator and outputting torque from the drive motor 3. , and the first shaft 28 and the second shaft 29 rotate integrally. As a result, torque from the drive motor 3 is transmitted to the pair of drive wheels 6 via the power transmission mechanism 4 and the differential gear 1 .

On the other hand, during coasting with the accelerator off, the connection/disengagement state of the reverse input cutoff clutch 30 is switched according to the rotation speed of the driving wheels 6 .

Specifically, the rotational speed of the driving wheel 6 is high, and the force applied to the pair of engaging elements 34 based on the drag resistance of the input portion 33 in the direction of bringing the pair of pressing surfaces 68 closer to the pressed surface 50; While the resultant force F of the centrifugal force acting on the pair of engaging elements 34 is greater than the force f applied by the pair of force applying members 35 to the pair of engaging elements 34, the reverse input interrupting clutch 30 is locked. maintained at Therefore, the rotational torque of the pair of drive wheels 6 is transmitted to the output shaft 3a of the drive motor 3 via the power transmission mechanism 4, and the drive motor 3 operates as a generator to perform regenerative braking.

On the other hand, when the rotational speed of the driving wheels 6 slows down and the resultant force becomes equal to or less than the force f applied to the pair of engaging elements 34 by the pair of force applying members 35, the reverse input cutoff clutch 30 is switched to the free state. Instead, the first shaft 28 and the second shaft 29 idle against each other. As a result, the pair of drive wheels 6 are disconnected from the drive motor 3 and the power transmission mechanism 4 . Therefore, the loss at the meshing portion of the drive motor 3 and the power transmission mechanism 4 can be reduced, and the distance traveled by inertia can be increased.

As described above, in the differential gear 1 of the present embodiment, the reverse input cut-off clutch 30 is switched between the disengaged and engaged states in accordance with changes in the rotation speed of the drive wheels 6 during inertia running, so that the pair of drive wheels 6, the power transmission mechanism 4, and the drive motor 3 are enabled/disabled. Therefore, it is not necessary to strictly adjust the timing of engaging the clutch device, unlike the differential device described in Japanese Patent Application Laid-Open No. 2020-46065. In short, it is possible to easily switch between the pair of drive wheels 6, the power transmission mechanism 4, and the drive motor 3 to enable or disable torque transmission.

In the reverse input cut-off clutch 30 incorporated in the differential gear 1 of this embodiment, the pair of engaging elements 34 has pressing surfaces 68 at two circumferentially separated locations on the radial outer surface. . Therefore, according to the reverse input cutoff clutch 30 of this example, compared to the case where one pressing surface is frictionally engaged with the pressed surface like the reverse input cutoff clutch described in Japanese Patent Application Laid-Open No. 2020-8124. Thus, the frictional engagement force between the pressed surface 50 and the pair of pressing surfaces 68 can be increased by the wedge effect. Therefore, when the frictional engagement force between the output portion 32 and the engaging element 34 is the same, the reverse input cutoff clutch 30 of this example is compared with the reverse input cutoff clutch described in Japanese Patent Application Laid-Open No. 2020-8124. Outer diameter and/or axial dimensions can be reduced.

Further, in the reverse input interrupting clutch disclosed in Japanese Patent Application Laid-Open No. 2020-8124, the dimension of the bottom surface of the engagement recess (input engagement recess) formed on the radially inner surface of the engaging member in the second direction is determined by the input member. It is larger than the dimension in the long axis direction of the cam portion (input engagement cam). Therefore, in a free state in which the input member and the output member are idling with respect to each other, there is a possibility that the engaging member may shift in the second direction with respect to the input member. Therefore, it is necessary to ensure that the radial dimension of the gap between the pressed surface and the pressing surface in the free state is large to some extent.

On the other hand, in the reverse input interrupting clutch 30 of this example, in the free state, the short-axis direction end of the cam portion 57 of the input portion 33 and the engaging recesses 69 of the pair of engaging elements 34 are arranged in the second direction. It is engaged without backlash. Therefore, in the free state, it is possible to prevent the pair of engaging elements 34 from shifting with respect to the input portion 33 in the second direction. Therefore, the radial dimension of the gap 76 between the pressed surface 50 and the pair of pressing surfaces 68 in the free state can be reduced. From this point of view as well, the reverse input cutoff clutch 30 of this example can easily be further miniaturized compared to the reverse input cutoff clutch described in Japanese Patent Laid-Open No. 2020-8124.

In the reverse input cut-off clutch 30 of this example, the width dimension in the major axis direction of the cam portion 57 is made smaller toward the ends in the minor axis direction, and the width dimension in the second direction of the engaging recess 69 is , increasing toward the opening side. Therefore, as shown in FIG. 6 (or FIG. 7) → FIG. 8 and FIG. 9 (A) (or FIG. 9 (B)) → FIG. At the time of switching, a pair of side surface portions 71 located on both sides of the engaging recess 69 in the second direction are guided by a pair of connection surface portions 62 located on both sides in the long axis direction of the ends of the cam portion 57 in the short axis direction. As a result, movement of the pair of engaging elements 34 in the second direction is restricted. Therefore, in the free state, even when the short axis direction end of the cam portion 57 of the input portion 33 and the engaging recesses 69 of the pair of engaging elements 34 are engaged with each other without play in the second direction, the locking is possible. It is possible to smoothly switch from the state to the free state.

In the differential gear 1 of this example, the minimum diameter of the circumscribed circle of the cam portion 57 (the interval between the pair of first flat surface portions 60) of the first shaft 28 is It is smaller than the portion (the outer diameter of the male spline portion 27) that is coupled and fixed to the side gear 9a on one side in the axial direction. However, although illustration is omitted, when carrying out the present invention, the minimum value of the circumscribed circle diameter of the cam portion can be made larger than the portion of the first shaft that is coupled and fixed to the side gear.

Although the reverse input interrupting clutch 30 of this embodiment has one pair (two pieces) of the engaging elements 34, when carrying out the present invention, the number of engaging elements constituting the reverse input interrupting clutch is set to one. can be used, or three or more can be used. Further, the engagement structure between the input section and the output section and the engaging element is not limited to the structure shown in the embodiment. As long as the rotation of the input section can be converted into the radial movement of the engaging element, various conventionally known structures can be adopted. Also, the force applying member may employ various structures as long as it can apply force to the engaging elements so that the pair of pressing surfaces are separated from the pressed surfaces. Also, the number of force applying members incorporated in the reverse input cutoff clutch device is not limited to two, and may be one or three or more. When only one force application member is provided, the force application member can be arranged in the through hole formed in the cam portion.

Further, when the differential gear with disconnect mechanism of the present invention is implemented, the first shaft and the second shaft are connected as a reverse input cutoff clutch when the number of revolutions of the first shaft is greater than a predetermined value. In contrast to rotating integrally, when the number of rotations of the first shaft is equal to or less than the predetermined value, the first shaft and the second shaft can be idly rotated with each other. structure can be adopted. For example, instead of the reverse input cut-off clutch 30 of this example, a reverse input cut-off clutch described in Japanese Patent Application Laid-Open No. 2020-8124 can be employed.

Further, the differential gear with a disconnect mechanism of the present invention is not limited to the drive device of an electric vehicle (EV) using a drive motor as a drive source, but is also applicable to a drive device of a fossil fuel vehicle using an engine as a drive source, a drive motor and The present invention can also be applied to a hybrid vehicle (HV) drive system using an engine as a drive source.

Reference Signs List 1 differential gear 2 electric vehicle drive device 3 drive motor 3a output shaft 4 power transmission mechanism 4a drive gear 4b intermediate shaft 4c intermediate gear 4d final reduction gear 5a, 5b drive shaft 6 drive wheel 7 differential case 8 pinion gear 9a, 9b side gear 10 Ring gear 11 case member 12 gear member 13a, 13b small-diameter tubular portion 14a, 14b connection portion 15 large-diameter tubular portion 16 circular hole 17 outward flange portion 18 support shaft 19a, 19b tapered roller bearing 20 fixed portion 21 tubular portion 22 inward flange portion 23 bolt 24 center hole 25 radial bearing 26 spline hole 27 male spline portion 28 first shaft 29 second shaft 30 reverse input blocking clutch 31 housing 32 output portion 33 input portion 34 engaging element 35 force applying member 36 side plate portion 37 large diameter tube Portion 38 Small-diameter cylindrical portion 39 Inward flange portion 40 Through-hole 41 Bolt 42 Output shaft portion 43 Cylindrical portion 44 Side plate portion 45 Small-diameter portion 46 Large-diameter portion 47 Small-diameter cylindrical surface portion 48 Large-diameter cylindrical surface portion 49 Stepped portion 50 Pressed surface 51 Radial needle Bearing 52 Outer ring 53 Cage 54 Needle 55 Seal member 56 Large diameter shaft portion 57 Cam portion 58 Small diameter shaft portion 59 Outward flange portion 60 First flat surface portion 61 Second flat surface portion 62 Connection surface portion 63a, 63b Radial rolling bearing 67a, 67b, 67c, 67d Retaining ring 68 Pressing surface 69 Engagement concave portion 70 Bottom surface 71 Side surface portion 72 Notch portion 73 Locking hole 74 Coil portion 75 Locking arm portion 76 Gap 77 Screw hole

Claims (8)

a differential case having a torque input;
at least one pinion gear supported with respect to the differential case so as to be rotatable about an axis perpendicular to the central axis of the differential case;
a pair of side gears supported coaxially with the central axis of the differential case so as to be rotatable relative to the differential case and meshing with the pinion gear;
a pair of drive shafts each of which has its base end coupled and fixed to the pair of side gears;
with
one of the pair of drive shafts,
a first shaft having a base end coupled and fixed to one side gear of the pair of side gears;
a second shaft arranged coaxially with the first shaft;
a reverse input cutoff clutch that connects the first shaft and the second shaft;
and
The reverse input cut-off clutch integrally rotates the first shaft and the second shaft when the rotation speed of the first shaft is greater than a predetermined value. is equal to or less than the predetermined value, causing the first shaft and the second shaft to idle against each other;
Differential gear with disconnect mechanism. The reverse input cutoff clutch is
an output portion having a pressed surface on its inner peripheral surface and rotating integrally with the second shaft;
an input portion having a cam portion arranged radially inward of the surface to be pressed and rotating integrally with the first shaft;
an engaging element having a pressing surface facing the pressed surface and arranged radially between the pressed surface and the cam portion;
a force applying member that applies a force to the engaging element in a direction in which the pressing surface separates from the pressed surface;
with
A force acting on the engaging element in a direction to bring the pressing surface closer to the pressed surface along with the rotation of the input portion and the rotation of the engaging element is larger than the force applied to the engaging element by the force applying member. In this case, the engaging element moves radially in a direction in which the pressing surface approaches the surface to be pressed, and frictionally engages the pressing surface with the surface to be pressed, so that the input portion and the output portion is rotated integrally, the input portion is not rotated, or the pressing surface that acts on the engaging element along with the rotation of the input portion and the rotation of the engaging element is the pressed surface. When the force in the direction of approaching the surface is equal to or less than the force applied to the engager by the force applying member, the force applied to the engager by the force applying member is applied to the pressed surface and the pressing surface. By forming a gap between, the input section and the output section are idly rotated with each other
2. The differential gear with disconnect mechanism according to claim 1. The engaging element has a pair of pressing surfaces spaced apart from each other in the circumferential direction,
3. A differential gear with disconnect mechanism according to claim 2. The input section has an input section side guide section, and the engaging element has an engaging section side guide section,
In a state where the gap is formed between the pressed surface and the pressing surface based on the force applied by the force applying member to the engaging element, the input section side guide section and the engaging element side guide section engages without rattling in a first direction, which is a far-near direction of the pressing surface with respect to the pressed surface, and a second direction orthogonal to the central axis of the input portion;
4. A differential gear with disconnect mechanism according to claim 2 or 3. A pair of the engaging elements are provided so as to sandwich the cam portion from the outside in the radial direction,
A differential gear with a disconnect mechanism according to any one of claims 2 to 4. The force applying member is provided so as to bridge between the pair of the engaging elements,
6. A differential gear with disconnect mechanism according to claim 5. wherein the force imparting member is composed of an elastic member;
A differential gear with a disconnect mechanism according to any one of claims 2 to 6. The minimum value of the circumscribed circle diameter of the cam portion is larger than the outer diameter of the portion of the first shaft that is coupled and fixed to the one side gear.
A differential gear with a disconnect mechanism according to any one of claims 2 to 7.

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