Clutch device

Abstract

A movable dog part (90) is provided so as to be unable to rotate relative to a first fixed dog part (70) and able to move in the axial direction, moves in the axial direction relative to the first fixed dog part (70) by means of power output from an actuator (300), and allows transmission of torque between a first transmission part (61) and a second transmission part (62) when meshing with a second fixed dog part (80). A first stopper part (74) is provided to the first fixed dog part (70), and can restrict the movement of the movable dog part (90) to the side opposite to the second fixed dog part (80) by abutting on a first movable dog end part (901), which is one end part in the axial direction of the movable dog part (90). The first stopper part (74) is formed in a tapered shape so as to approach an axis (Ax1) of the first fixed dog part (70) from the side opposite to the second fixed dog part (80) toward the second fixed dog part (80) side.

Description

Clutch device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2024-109852, filed on July 8, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a clutch device.

[0003] Conventionally, there has been known a clutch device that can allow or interrupt the transmission of torque between a first transmission part and a second transmission part that are rotatable relative to each other. For example, in the clutch device disclosed in Patent Document 1, a movable dog part moves and meshes with a fixed dog part, thereby bringing the clutch into an engaged state and allowing the transmission of torque between the first transmission part and the second transmission part.

[0004] Japanese Patent Application Laid-Open No. 2021-144021

[0005] In the clutch device of Patent Document 1, the axial positions of the movable dog portion and the fixed dog portion are determined by many component elements, which can lead to large axial misalignment. In particular, in a spline-type clutch, play is required in the meshing of the splines due to manufacturing and structural reasons to facilitate sliding, which can lead to even larger axial misalignment. Large axial misalignment can make it difficult to control the clutch device with high precision.

[0006] An object of the present disclosure is to provide a clutch device that reduces axial misalignment between a movable dog portion and a fixed dog portion and can be controlled with high precision.

[0007] A first aspect of a clutch device according to the present disclosure includes an actuator, a first transmission part, a second transmission part, a first fixed dog part, a second fixed dog part, a movable dog part, and a stopper part. The actuator is capable of outputting power when energized. The second transmission part is rotatable relative to the first transmission part.

[0008] The first fixed dog portion is provided so as to be rotatable integrally with the first transmission portion. The second fixed dog portion is provided so as to face the first fixed dog portion in the axial direction so as to be rotatable integrally with the second transmission portion. The movable dog portion is provided so as to be non-rotatable relative to the first fixed dog portion but movable relative to the first fixed dog portion in the axial direction, and moves relative to the first fixed dog portion in the axial direction due to power output from the actuator. When the movable dog portion engages with the second fixed dog portion, it is possible to allow transmission of torque between the first transmission portion and the second transmission portion.

[0009] The stopper portion is provided on the first fixed dog portion and is capable of restricting movement of the movable dog portion toward the opposite side from the second fixed dog portion by abutting against a movable dog end portion, which is one axial end of the movable dog portion. The stopper portion is formed in a tapered shape or a rounded corner shape so as to approach the axis of the first fixed dog portion as it moves from the side opposite to the second fixed dog portion toward the second fixed dog portion.

[0010] In a second aspect of the clutch device according to the present disclosure, the end of the movable dog is formed in a tapered or rounded corner shape so as to approach the axis of the movable dog as it moves from the side opposite the second fixed dog toward the second fixed dog.

[0011] Therefore, in the first or second aspect, when the movable dog moves toward the stopper and the end of the movable dog abuts against the stopper, the movable dog is aligned with the first fixed dog so that the axes of the first fixed dog and the movable dog are substantially aligned. This reduces axial misalignment between the movable dog and the first and second fixed dog, thereby enabling high-precision control of the clutch device.

[0012] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a schematic diagram showing a clutch device according to a first embodiment and a vehicle to which the same is applied, Fig. 2 is a cross-sectional view showing the clutch device according to the first embodiment, Fig. 3 is a cross-sectional view showing a movable dog portion and its vicinity of the clutch device according to the first embodiment, Fig. 4 is a schematic cross-sectional view showing the movable dog portion and its vicinity of the clutch device according to the first embodiment, Fig. 5 is a diagram for explaining the operation of the clutch device according to the first embodiment, in which (A) is a diagram showing the movable dog portion in the "release position" and (B) is a diagram showing the movable dog portion in the "engagement position", Fig. 6 is a perspective view showing the first transmission portion and the first fixed dog portion of the clutch device according to the first embodiment, Fig. 7 is a perspective view showing the movable dog portion of the clutch device according to the first embodiment, and Fig. 8 is a cross-sectional view showing a clutch device according to a second embodiment. 9 is a perspective view showing a part of a clutch device according to a second embodiment, FIG. 10 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a third embodiment, FIG. 11 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a fourth embodiment, FIG. 12 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a fifth embodiment, FIG. 13 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a sixth embodiment, FIG. 14 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a seventh embodiment, FIG. 15 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to an eighth embodiment, and FIG. 16 is a schematic cross-sectional view showing a movable dog portion and its vicinity of a clutch device according to a ninth embodiment.

[0013] Hereinafter, clutch devices according to a number of embodiments will be described with reference to the drawings. Note that substantially the same components in the number of embodiments will be denoted by the same reference numerals, and descriptions thereof will be omitted.

[0014] (First embodiment) A clutch device according to a first embodiment and a vehicle to which the clutch device is applied are shown in Fig. 1. The clutch device 10 is mounted on a vehicle 1 such as an electric vehicle.

[0015] The vehicle 1 is equipped with a motor generator 2, a reducer 17, a differential 9, a differential shaft 11, an axle case 16, a clutch device 10, wheel shafts 12, wheels 13, wheel shafts 14, wheels 15, an electronic control unit (hereinafter referred to as "ECU") 100 as a "control unit", and the like.

[0016] The motor generator 2 is used as a drive source for driving the vehicle 1, and is capable of outputting torque when energized. The motor generator 2 is capable of generating electricity through regenerative operation. The speed reducer 17 is capable of reducing the torque from the motor generator 2. The differential 9 is a differential device that distributes the torque from the speed reducer 17 to the wheels 13 and 15. The clutch device 10 is provided between the differential 9 and the wheels 13, and is used to allow or block the transmission of torque between the differential 9 and the wheels 13.

[0017] More specifically, the reducer 17 has a first gear shaft 3, a second gear shaft 4, a first small-diameter gear 5, a first large-diameter gear 6, a second small-diameter gear 7, and a second large-diameter gear 8. The first gear shaft 3 is connected to the motor generator 2 and is rotatable integrally with the motor generator 2. The first small-diameter gear 5 is coaxial with the first gear shaft 3 so as to be rotatable integrally with the first gear shaft 3. The second gear shaft 4 is parallel to the first gear shaft 3. The first large-diameter gear 6 has an outer diameter larger than that of the first small-diameter gear 5 and is capable of meshing with the first small-diameter gear 5, and is coaxial with the second gear shaft 4 so as to be rotatable integrally with the second gear shaft 4. The second small-diameter gear 7 has an outer diameter smaller than that of the first large-diameter gear 6, and is provided coaxially with the second gear shaft 4 so as to be rotatable integrally with the second gear shaft 4. The second large-diameter gear 8 has an outer diameter smaller than that of the second small-diameter gear 7, and is provided so as to be able to mesh with the second small-diameter gear 7. With this configuration, the torque from the motor generator 2 is reduced by the reducer 17 and output from the second large-diameter gear 8.

[0018] Here, "coaxial" does not necessarily mean that the axes of both are strictly aligned, but also includes a state in which they slightly intersect within the scope of error or common technical knowledge, and a state in which they are approximately parallel (the same applies below).

[0019] The differential 9 is provided to be connected to the second large diameter gear 8. One end of a differential shaft 11 is provided to be connected to the differential 9.

[0020] The axle case 16 is formed to be able to accommodate, for example, the motor generator 2, the speed reducer 17, the differential 9, the differential shaft 11, etc., and is provided on the vehicle 1.

[0021] The clutch device 10 is attached to the axle case 16. A first transmission unit 61 (described later) of the clutch device 10 is connected to one end of the wheel shaft 12. A second transmission unit 62 (described later) of the clutch device 10 is connected to the other end of the differential shaft 11. The other end of the wheel shaft 12 is connected to the wheel 13. Here, the wheel 13 is, for example, the wheel on the rear left side of the vehicle 1.

[0022] One end of the wheel shaft 14 is connected to the differential 9. The other end of the wheel shaft 14 is connected to a wheel 15. Here, the wheel 15 is, for example, a wheel on the rear right side of the vehicle 1.

[0023] With the above-described configuration, when the clutch device 10 allows torque transmission between the second transmission part 62 connected to the differential shaft 11 and the first transmission part 61 connected to the wheel shaft 12, torque transmission between the motor generator 2 and the wheels 13 and 15 is allowed, and the vehicle 1 can run using the torque of the motor generator 2, or the motor generator 2 can operate regeneratively.

[0024] The ECU 100 is a small computer having a CPU as a calculation means, a ROM, a RAM, etc. as storage means, and an I / O as an input / output means. The ECU 100 executes calculations in accordance with a program stored in the ROM, etc., based on information such as signals from various sensors provided in various parts of the vehicle 1, and controls the operation of various devices and equipment of the vehicle 1. In this way, the ECU 100 executes a program stored in a non-transitory tangible recording medium. Execution of this program results in the execution of a method corresponding to the program.

[0025] The ECU 100 can control the operation of the motor generator 2 based on information such as signals from various sensors. The ECU 100 can also control the operation of the clutch device 10 by controlling the operation of an actuator 300 (described later).

[0026] As shown in Figure 2, the clutch device 10 includes an actuator 300, a first transmission part 61, a second transmission part 62, a first fixed dog part 70, a second fixed dog part 80, a movable dog part 90, and a first stopper part 74 as a "stopper part." The actuator 300 is capable of outputting power when energized. The second transmission part 62 is rotatable relative to the first transmission part 61.

[0027] The first fixed dog portion 70 is provided so as to be rotatable integrally with the first transmission portion 61. The second fixed dog portion 80 is provided so as to face the first fixed dog portion 70 in the axial direction so as to be rotatable integrally with the second transmission portion 62. The movable dog portion 90 is provided so as to be non-rotatable relative to the first fixed dog portion 70 but movable relative to the first fixed dog portion 70 in the axial direction, and moves relative to the first fixed dog portion 70 in the axial direction due to power output from the actuator 300. When the movable dog portion 90 engages with the second fixed dog portion 80, it is possible to transmit torque between the first transmission portion 61 and the second transmission portion 62.

[0028] The first stopper portion 74 is provided on the first fixed dog portion 70 and can restrict movement of the movable dog portion 90 in the opposite direction to the second fixed dog portion 80 by abutting against the first movable dog end portion 901, which is the ``movable dog end portion'' that is one axial end of the movable dog portion 90.

[0029] The configuration of the clutch device 10 will be described in more detail below.

[0030] 2, the clutch device 10 includes a first case 21 and a second case 22. The first case 21 is attached to the axle case 16 with bolts 201 so as to form a space 200 between the first case 21 and the outer wall of the axle case 16. The second case 22 is provided so as to be joined to the first case 21 in the space 200.

[0031] The motor 30 is attached to the side of the first case 21 opposite the space 200. The motor 30 has a stator, a coil, a rotor (not shown), and a motor shaft 31. When current is applied to the coil, the rotor rotates and torque is output from the motor shaft 31. The tip of the motor shaft 31 is located in a hole formed in the first case 21.

[0032] The clutch device 10 includes a rotational / translation unit 40. The rotational / translation unit 40 is capable of converting rotational motion due to torque from the motor 30 into translational motion. The rotational / translation unit 40 has a ball screw shaft 41 as a "rotating unit." The ball screw shaft 41 is formed in a rod shape. A spiral groove is formed on the outer peripheral wall of the ball screw shaft 41. The ball screw shaft 41 is supported at both ends by a bearing 261 provided in the first case 21 and a bearing 262 provided in the second case 22. Here, the bearings 261 and 262 are ball bearings. In addition, bearings 263, 264, and 265, which will be described later, are also ball bearings. The tip of the motor shaft 31 is connected to the end of the ball screw shaft 41 on the bearing 261 side. This allows the ball screw shaft 41 to rotate together with the motor shaft 31.

[0033] The rotation-translation part 40 has a ball screw nut 43 and a flange 44 as a "translation part." The ball screw nut 43 is formed in a cylindrical shape. A spiral groove is formed on the inner peripheral wall of the ball screw nut 43. The ball screw nut 43 is provided radially outside the ball screw shaft 41, between the bearing 261 and the bearing 262. The ball screw nut 43 is movable relative to the ball screw shaft 41 in the axial direction.

[0034] The flange 44 is formed in a plate shape. The flange 44 has a hole penetrating the flange 44 in the plate thickness direction, and is attached to the ball screw nut 43 such that the inner edge of the hole engages with a groove formed in the outer peripheral wall of the ball screw nut 43. This allows the flange 44 to move axially together with the ball screw nut 43, i.e., to translate.

[0035] The rotation-translation unit 40 has balls (not shown). A plurality of balls are provided so as to be able to roll between a spiral groove formed in the ball screw shaft 41 and a spiral groove formed in the ball screw nut 43. As a result, when the ball screw shaft 41 rotates, the balls roll, and the ball screw nut 43 moves axially relative to the ball screw shaft 41. In this way, the rotation-translation unit 40 constitutes a so-called ball screw.

[0036] The clutch device 10 includes a fork 50. The fork 50 has a fork base 51 and a fork engagement portion 52. The fork base 51 is formed, for example, in the shape of a rectangular plate. The fork engagement portion 52 is formed in a substantially arc shape. The fork engagement portion 52 is formed integrally with the fork base 51 such that its central outer edge is connected to one side of the fork base 51.

[0037] The fork 50 is formed with a fork nut hole 501, a fork guide hole 502, and a fork pin hole 503. The fork nut hole 501, the fork guide hole 502, and the fork pin hole 503 are formed to penetrate the fork base 51 in the plate thickness direction. The fork nut hole 501 and the fork guide hole 502 are formed to be aligned along the arrangement direction of the fork base 51 and the fork engagement part 52. Two fork pin holes 503 are formed with the fork nut hole 501 sandwiched between them. Here, the two fork pin holes 503 are formed along a direction perpendicular to the arrangement direction of the fork nut hole 501 and the fork guide hole 502.

[0038] The fork 50 is provided on the bearing 261 side of the flange 44 so that the ball screw nut 43 is inserted into the fork nut hole 501. The fork 50 is movable axially relative to the ball screw nut 43 on the bearing 261 side of the flange 44.

[0039] The rotation / translation unit 40 has a link pin 45. The link pin 45 is formed in a rod shape. The link pin 45 has a stopper portion 451. The stopper portion 451 is formed in a disk shape at one end of the link pin 45.

[0040] The link pin 45 is provided so that the other end side is inserted through the fork pin hole 503 and a hole formed in the flange 44. The end of the link pin 45 opposite the stopper portion 451 protrudes from the hole in the flange 44. A nut 46 is threadedly engaged with the end of this link pin 45. When the nut 46 and the flange 44 are in contact with each other, movement of the link pin 45 toward the bearing 261 is restricted.

[0041] An annular pin step surface 452 is formed on the outer peripheral wall of the link pin 45. The fork 50 is movable in the axial direction relative to the link pin 45 between the pin step surface 452 and the surface of the flange 44 facing the bearing 261. When the fork 50 abuts against the pin step surface 452, movement of the fork 50 toward the bearing 261 relative to the link pin 45 is restricted, and when the fork 50 abuts against the surface of the flange 44 facing the bearing 261, movement of the fork 50 toward the opposite side of the bearing 261 relative to the flange 44 is restricted.

[0042] The rotation-translation unit 40 has a standby spring 47. The standby spring 47 is a coil spring and is provided radially outward of each of the two link pins 45 on the side of the fork base 51 opposite the flange 44. The inner diameter of the standby spring 47 is slightly larger than the outer diameter of the link pin 45 and smaller than the outer diameter of the stopper portion 451. One end of the standby spring 47 abuts against the stopper portion 451, and the other end abuts against the fork 50. The standby spring 47 is provided in a compressed state between the stopper portion 451 and the fork 50. In other words, the standby spring 47 is set to have a preload. The link pin 45 supports the standby spring 47 and can guide the operation of the standby spring 47 when it expands or contracts.

[0043] The clutch device 10 includes a fork guide shaft 23. The fork guide shaft 23 is rod-shaped. The fork guide shaft 23 is inserted through the fork guide hole 502, with one end fitting into the first case 21 and the other end fitting into the second case 22. A bushing 24 and a bushing guide 25 are provided radially outward from the fork guide shaft 23. The bushing 24 is cylindrical, with its inner peripheral wall slidably fitted on the outer peripheral wall of the fork guide shaft 23. The bushing guide 25 is cylindrical, with its outer peripheral wall fitting into the inner peripheral wall of the fork guide hole 502. The bushing guide 25 can hold the bushing 24. The fork guide shaft 23 guides the translational movement of the fork 50 and restricts relative rotation of the fork 50 with respect to the first case 21 or the second case 22. In other words, the fork guide shaft 23 also functions as a rotation stopper for the fork 50.

[0044] 2 and 3, the second transmission part 62 is formed in a cylindrical shape. One end of the second transmission part 62 is supported by a bearing 263 provided in the axle case 16. The other end of the second transmission part 62 is connected to the differential shaft 11.

[0045] The first transmission part 61 is formed in a cylindrical shape. One end of the first transmission part 61 is supported by a bearing 264 provided in the first case 21. The other end of the first transmission part 61 is located inside one end of the second transmission part 62.

[0046] The wheel shaft 12 is connected to the inside of the first transmission part 61. The first transmission part 61 and the wheel shaft 12 are connected by a spline coupling. An oil seal 271 is provided on the first case 21 on the opposite side of the bearing 263 with respect to the bearing 264. The oil seal 271 is provided so as to be slidable along the outer peripheral wall of the wheel shaft 12, and can maintain an airtight or liquid-tight seal between the opening of the first case 21 and the outer peripheral wall of the wheel shaft 12.

[0047] The first fixed dog portion 70 includes a first fixed dog cylindrical portion 71, a first fixed dog protrusion 72, and a first fixed dog tooth portion 73. The first fixed dog cylindrical portion 71 is cylindrical and integrally formed with the first transmission portion 61 such that its inner peripheral wall is connected to the outer peripheral wall at the axial center of the first transmission portion 61. Therefore, the first fixed dog cylindrical portion 71 can rotate integrally with the first transmission portion 61. The first fixed dog protrusion 72 is annularly formed so as to protrude radially outward from the outer peripheral wall at one end of the first fixed dog cylindrical portion 71. The first fixed dog tooth portion 73 is formed on the outer peripheral wall of the first fixed dog cylindrical portion 71 so as to extend in the axial direction while protruding radially outward. A plurality of first fixed dog tooth portions 73 are formed at equal intervals around the circumferential direction of the first fixed dog cylindrical portion 71.

[0048] A bearing 265 is provided between the second transmission part 62 and the first fixed dog part 70. The bearing 265 is a so-called thrust ball bearing. The bearing 265 can support an axial load between the first transmission part 61 and the second transmission part 62 when they rotate relative to each other.

[0049] The second fixed dog portion 80 includes a second fixed dog cylinder portion 81, a second fixed dog plate portion 82, a second fixed dog teeth portion 83, and a second fixed dog target 85. The second fixed dog portion 80 is cylindrically formed. The second fixed dog plate portion 82 is plate-shaped and extends radially outward from one end of the second fixed dog cylinder portion 81. The second fixed dog teeth portion 83 is formed to extend axially while protruding radially outward from the outer peripheral wall of the second fixed dog cylinder portion 81. A plurality of second fixed dog teeth portions 83 are formed at equal intervals around the circumferential direction of the second fixed dog cylinder portion 81. Here, the number of second fixed dog teeth portions 83 formed is the same as the number of first fixed dog teeth portions 73. The second fixed dog target 85 is formed to protrude radially outward from the outer edge of the second fixed dog plate portion 82. A plurality of second fixed dog targets 85 are formed in the circumferential direction of the second fixed dog plate portion 82 .

[0050] The second fixed dog portion 80 is spline-coupled to the second transmission portion 62 by spline teeth formed on the inner peripheral wall of the second fixed dog cylindrical portion 81 meshing with spline teeth formed on the outer peripheral wall of the end portion of the second transmission portion 62. Therefore, the second fixed dog portion 80 can rotate integrally with the second transmission portion 62. The second fixed dog portion 80 is provided so as to be immovable relative to the second transmission portion 62 in the axial direction.

[0051] The movable dog portion 90 includes a movable dog cylinder portion 91, a movable dog plate portion 92, a movable dog teeth portion 93, a movable dog recess 94, and a movable dog target 95. The movable dog cylinder portion 91 is formed in a cylindrical shape. The movable dog plate portion 92 is formed in a plate shape so as to extend radially outward from one end of the movable dog cylinder portion 91. The movable dog teeth portion 93 is formed so as to extend axially while protruding radially inward from the inner peripheral wall of the movable dog cylinder portion 91. A plurality of movable dog teeth portions 93 are formed at equal intervals around the circumferential direction of the movable dog cylinder portion 91. The number of movable dog teeth portions 93 is the same as the number of first fixed dog teeth portions 73 and second fixed dog teeth portions 83. The movable dog teeth portions 93 can mesh with the first fixed dog teeth portions 73 or the second fixed dog teeth portions 83.

[0052] The movable dog recess 94 is formed in an annular shape so as to be recessed radially inward from the outer peripheral wall of the movable dog cylinder portion 91. The movable dog target 95 is formed so as to protrude radially outward from the outer edge of the movable dog plate portion 92. A plurality of movable dog targets 95 are formed in the circumferential direction of the movable dog plate portion 92.

[0053] The movable dog portion 90 is provided radially outward of the first fixed dog portion 70 so that the movable dog tooth portion 93 can mesh with the first fixed dog tooth portion 73 and move axially relative to the first fixed dog portion 70. The movable dog portion 90 can move toward the second fixed dog portion 80, so that the movable dog tooth portion 93 can mesh with the second fixed dog tooth portion 83.

[0054] The first stopper portion 74 is formed on the movable dog portion 90 side of the first fixed dog protrusion portion 72 .

[0055] The first movable dog end portion 901 corresponds to the inner edge portion of the movable dog portion 90 , particularly the end portion of the movable dog cylindrical portion 91 opposite to the second fixed dog portion 80 .

[0056] A second stopper portion 84 is formed on the inner edge of the second fixed dog plate portion 82 on the surface facing the movable dog portion 90 .

[0057] When the first movable dog end 901 abuts against the first stopper portion 74, the movable dog portion 90 is restricted from moving in the opposite direction from the second fixed dog portion 80. When the second movable dog end 902, which is the end of the movable dog portion 90 opposite to the first movable dog end 901, abuts against the second stopper portion 84, the movable dog portion 90 is restricted from moving toward the second fixed dog portion 80. In this way, the movable dog portion 90 is capable of reciprocating axially between the first stopper portion 74 and the second stopper portion 84.

[0058] The first fixed dog portion 70 , the second fixed dog portion 80 , and the movable dog portion 90 constitute a clutch portion 700 that allows or blocks the transmission of torque between the first transmission portion 61 and the second transmission portion 62 .

[0059] When the movable dog portion 90 moves toward the second fixed dog portion 80 relative to the first fixed dog portion 70, the movable dog teeth portion 93 can mesh with the second fixed dog teeth portion 83. When the movable dog teeth portion 93 and the second fixed dog teeth portion 83 are in mesh with each other, i.e., when the clutch portion 700 is in an engaged state, torque transmission between the first transmission portion 61 and the second transmission portion 62 is permitted. On the other hand, when the movable dog teeth portion 93 and the second fixed dog teeth portion 83 are not in mesh with each other, i.e., when the clutch portion 700 is in a disengaged state, torque transmission between the first transmission portion 61 and the second transmission portion 62 is blocked.

[0060] The inner edge of the fork engagement portion 52 of the fork 50 engages with the movable dog recess 94 of the movable dog portion 90. As a result, when the fork 50 moves in translation, the movable dog portion 90 moves axially relative to the first fixed dog portion 70 and the first transmission portion 61.

[0061] The first stopper portion 74 is tapered so as to approach the axis Ax1 of the first fixed dog portion 70 from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 (see FIGS. 3, 4, and 6). In other words, the first stopper portion 74 has a constant rate of reduction in outer diameter from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80.

[0062] The first movable dog end 901 is tapered so as to approach the axis Ax2 of the movable dog 90 from the side opposite the second fixed dog 80 toward the second fixed dog 80 (see FIGS. 3, 4, and 7). In other words, the first movable dog end 901 has a constant rate of reduction in its inner diameter from the side opposite the second fixed dog 80 toward the second fixed dog 80.

[0063] The first stopper portion 74 and the first movable dog end portion 901 are tapered (see FIGS. 3 and 4). The angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is the same as the angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90 (see FIG. 4). In this embodiment, the angles θ1 and θ2 are, for example, 45 degrees.

[0064] The ECU 100 can control the rotation of the motor shaft 31 by controlling the power supplied to the coil of the motor 30. In an initial state in which the coil of the motor 30 is not energized, the ball screw nut 43 is located on the motor 30 side of the ball screw shaft 41. At this time, the movable dog portion 90 is located radially outward of the first fixed dog portion 70 and is not engaged with the second fixed dog portion 80 (see (A) in FIGS. 2, 3, and 5). The position of the movable dog portion 90 at this time is referred to as the "release position."

[0065] In the initial state, when the motor shaft 31 rotates forward under the control of the ECU 100, the ball screw shaft 41 also rotates forward, and the ball screw nut 43 translates away from the motor 30. The fork 50, which is pressed against the flange 44 by the waiting spring 47, translates away from the first case 21 due to the translation of the ball screw nut 43. As a result, the movable dog 90 translates toward the second fixed dog 80, the movable dog teeth 93 and the second fixed dog teeth 83 mesh, and the clutch unit 700 enters an engaged state (see FIG. 5B). The position of the movable dog 90 at this time is referred to as the "engaged position."

[0066] When the clutch unit 700 is in an engaged state, if the motor shaft 31 rotates in the reverse direction under the control of the ECU 100, the ball screw shaft 41 also rotates in the reverse direction, and the ball screw nut 43 translates toward the motor 30. The fork 50, which is pressed against the flange 44 by the waiting spring 47, translates toward the first case 21 due to the translation of the ball screw nut 43. As a result, the movable dog 90 translates toward the opposite side from the second fixed dog 80, and the meshing between the movable dog tooth 93 and the second fixed dog tooth 83 is released, and the clutch unit 700 enters a disengaged state.

[0067] As described above, in this embodiment, the standby spring 47 provided between the stopper portion 451 of the link pin 45 and the fork 50 can bias the movable dog portion 90 axially toward the second fixed dog portion 80 via the fork 50. This can improve the engagement response speed between the movable dog portion 90 and the second fixed dog portion 80 and reduce the impact at the time of engagement.

[0068] The clutch device 10 includes a phase difference detector 101 (see FIG. 2 ). The phase difference detector 101 is capable of detecting the rotational phase difference between the movable dog portion 90 and the second fixed dog portion 80.

[0069] More specifically, the phase difference detection unit 101 is provided on the axle case 16 so as to be located radially outward of the movable dog plate unit 92 and the second fixed dog plate unit 82 (see FIG. 2 ). A magnetic circuit is disposed in the phase difference detection unit 101 so as to straddle the movable dog target 95 and the second fixed dog target 85. The phase difference detection unit 101 has a magnetic detection element capable of detecting a change in the direction (angle) of magnetic flux density generated from the yoke end of the magnetic circuit due to rotation of the movable dog unit 90 on which the movable dog target 95 is formed and the second fixed dog unit 80 on which the second fixed dog target 85 is formed. The phase difference detection unit 101 can detect the rotational phase difference between the movable dog unit 90 and the first transmission unit 61 and the second fixed dog unit 80 and the second transmission unit 62 based on the change in the direction (angle) of magnetic flux density detected by the magnetic detection element.

[0070] The ECU 100 can control the operation of the actuator 300 based on the rotational phase difference detected by the phase difference detection unit 101. More specifically, the ECU 100 can predict the timing at which the movable dog tooth portion 93 and the second fixed dog tooth portion 83 can mesh without collision and complete the engagement operation based on the rotational phase difference detected by the phase difference detection unit 101, and can control the operation of the motor 30 to move the movable dog portion 90 from the "disengaged position" to the "engaged position" in one go at that timing. This makes it possible to avoid collision between the movable dog tooth portion 93 and the second fixed dog tooth portion 83 and shorten the time until the engagement is completed.

[0071] As described above, in this embodiment, the first stopper portion 74 and the first movable dog end portion 901 are formed in a tapered shape. Therefore, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axis Ax1 of the first fixed dog portion 70 and the axis Ax2 of the movable dog portion 90 substantially coincide with each other.

[0072] The ECU 100 can control the operation of the actuator 300 so that the first movable dog end 901 is pressed against the first stopper portion 74 .

[0073] By controlling the ECU 100 to press the first movable dog end portion 901 against the first stopper portion 74, the movable dog portion 90 can be reliably aligned with the first fixed dog portion 70 at the "release position."

[0074] As described above, in this embodiment, the first stopper portion 74 is provided on the first fixed dog portion 70 and is able to restrict movement of the movable dog portion 90 toward the opposite side from the second fixed dog portion 80 by abutting against the first movable dog end portion 901, which serves as a “movable dog end portion” that is one axial end portion of the movable dog portion 90. The first stopper portion 74 is formed in a tapered shape so as to approach the axis Ax1 of the first fixed dog portion 70 as it moves from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 side.

[0075] Therefore, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axes of the first fixed dog portion 70 and the movable dog portion 90 substantially coincide with each other. This reduces axial misalignment between the movable dog portion 90 and the first fixed dog portion 70 and the second fixed dog portion 80. Therefore, the clutch device 10 can be controlled with high precision.

[0076] In addition, in this embodiment, the first movable dog end 901 is tapered so as to approach the axis Ax2 of the movable dog portion 90 as it moves from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 side.

[0077] By forming not only the first stopper portion 74 but also the first movable dog end portion 901 in a tapered shape, it is possible to have contact between tapered surfaces, as opposed to, for example, contact between the tapered first stopper portion 74 and the angular first movable dog end portion 901, i.e., contact between a tapered surface and an angular portion, which improves the strength of the member and reduces wear.

[0078] In this embodiment, the first stopper portion 74 and the first movable dog end portion 901 are tapered. An angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is the same as an angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90.

[0079] Therefore, the contact area between the first stopper portion 74 and the first movable dog end portion 901 can be increased, and the strength of the member can be further improved and wear can be reduced.

[0080] In this embodiment, the clutch device 10 includes a phase difference detection unit 101 and an ECU 100 as a "control unit." The phase difference detection unit 101 is capable of detecting the rotational phase difference between the movable dog portion 90 and the second fixed dog portion 80. The ECU 100 is capable of controlling the operation of the actuator 300 based on the rotational phase difference detected by the phase difference detection unit 101.

[0081] In this embodiment, the first stopper portion 74 and the first movable dog end portion 901 are tapered. Therefore, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axis Ax1 of the first fixed dog portion 70 and the axis Ax2 of the movable dog portion 90 substantially coincide with each other. This reduces axial misalignment between the movable dog portion 90 and the first fixed dog portion 70 and the second fixed dog portion 80. Therefore, variation in the radial position of the movable dog portion 90 at the "release position" can be suppressed. As a result, variation in the gap amount between the phase difference detection unit 101 and the movable dog target 95, which is the detection target, can be suppressed. This reduces detection errors of the rotational phase difference by the phase difference detection unit 101. This allows the rotational phase difference between the movable dog portion 90 and the second fixed dog portion 80 to be detected accurately, and the clutch device 10 can be controlled with high precision.

[0082] In addition, in this embodiment, the ECU 100 can control the operation of the actuator 300 so that the first movable dog end portion 901 is pressed against the first stopper portion 74 .

[0083] By controlling the ECU 100 to press the first movable dog end portion 901 against the first stopper portion 74, the movable dog portion 90 can be reliably aligned with the first fixed dog portion 70 at the "release position." This improves the accuracy of position detection at the zero point, which is the "release position," thereby improving the accuracy of threshold-reaching determination. Therefore, the clutch device 10 can be controlled with even higher precision.

[0084] Second Embodiment A clutch device according to a second embodiment is shown in Fig. 8. The second embodiment differs from the first embodiment in the configuration of the actuator 300 and the like.

[0085] In this embodiment, the actuator 300 is a solenoid 35. The solenoid 35 includes a fixed core, an electromagnetic coil, a movable core, a return spring, a solenoid case 351, a solenoid shaft 36, a clamping portion 37, and other components (not shown). The fixed core, the electromagnetic coil, the movable core, and the return spring are housed in the solenoid case 351. The fixed core is made of a magnetic material and is fixed inside the solenoid case 351. The electromagnetic coil generates magnetic flux when current is applied. The generated magnetic flux flows through the fixed core. The movable core is made of a magnetic material. The movable core is provided inside the solenoid case 351 so as to be able to reciprocate in the axial direction. The return spring is provided to bias the movable core toward one end of the solenoid case 351. The solenoid shaft 36 has one end connected to the movable core and the other end protruding from the other end of the solenoid case 351. The solenoid shaft 36 is reciprocable in the axial direction together with the movable core 36. The clamping portion 37 is fixed to the other end of the solenoid shaft 36 by a nut 38.

[0086] The solenoid 35 has a solenoid case 351 fixed to the first case 21 so that the clamping portion 37 is positioned inside the first case 21 .

[0087] The ECU 100 can control the operation of the solenoid 35 by controlling the supply of current to the electromagnetic coil. When the electromagnetic coil is not energized, the movable core is pressed against one end of the solenoid case 351 by the biasing force of the return spring. When the electromagnetic coil is energized under the control of the ECU 100, a magnetic flux is generated in the electromagnetic coil, and a magnetic circuit is formed between the fixed core and the movable core. This generates an attractive force between the fixed core and the movable core, and the movable core is attracted to the other end of the solenoid case 351 against the biasing force of the return spring. Therefore, the solenoid shaft 36 moves axially together with the movable core so that the amount of protrusion of the other end from the solenoid case 351 increases.

[0088] When the ECU 100 controls the electromagnetic coil to stop or reversely energize it, the biasing force of the return spring causes the movable core to move toward one end of the solenoid case 351. As a result, the solenoid shaft 36 moves axially together with the movable core so that the amount of protrusion of the other end from the solenoid case 351 decreases.

[0089] In this embodiment, a fork fulcrum hole 505 is formed between the fork base 51 and the fork engagement portion 52 of the fork 50. A fork fulcrum pin 506 is inserted into the fork fulcrum hole 505. Both ends of the fork fulcrum pin 506 are joined to the first case 21. This allows the fork 50 to swing around the fork fulcrum pin 506. A fork engagement member 55 is provided at the end of the fork engagement portion 52 of the fork 50 opposite the fork base 51.

[0090] 9 , the end of the fork base 51 opposite the fork engaging portion 52 is joined to the clamping portion 37. More specifically, the end of the fork base 51 opposite the fork engaging portion 52 is joined to the clamping portion 37 so as to be sandwiched between the first clamping piece 371 and the second clamping piece 372 of the clamping portion 37. This causes the fork 50 to swing in accordance with the amount of protrusion of the solenoid shaft 36 from the solenoid case 351.

[0091] 8, the second transmission part 62 is formed in a cylindrical shape. One end of the second transmission part 62 is supported by a bearing 263 provided in the first case 21. The wheel shaft 12 is connected to the inside of the second transmission part 62.

[0092] The first transmission part 61 is formed in a cylindrical shape. One end of the first transmission part 61 is supported by a bearing 264 provided on the outer peripheral wall of the second transmission part 62. The other end of the first transmission part 61 is connected to the differential shaft 11.

[0093] The first case 21 is provided to be joined to the axle case 16. An oil seal 271 is provided between the outer peripheral wall of the wheel shaft 12 and the opening of the first case 21.

[0094] Similar to the first embodiment, the first fixed dog portion 70 includes a first fixed dog cylindrical portion 71, a first fixed dog protrusion 72, and a first fixed dog tooth portion 73. The first fixed dog cylindrical portion 71 is cylindrical and integrally formed with the first transmission portion 61 such that its inner peripheral wall is connected to the outer peripheral wall of one end of the first transmission portion 61. Therefore, the first fixed dog cylindrical portion 71 can rotate integrally with the first transmission portion 61. The first fixed dog protrusion 72 is annularly formed and protrudes radially outward from the outer peripheral wall of one end of the first fixed dog cylindrical portion 71. The first fixed dog tooth portion 73 is formed on the outer peripheral wall of the first fixed dog cylindrical portion 71 so as to extend in the axial direction while protruding radially outward. A plurality of first fixed dog tooth portions 73 are formed at equal intervals around the circumferential direction of the first fixed dog cylindrical portion 71.

[0095] The second fixed dog portion 80 has a second fixed dog cylinder portion 81, a second fixed dog plate portion 82, and a second fixed dog teeth portion 83. The second fixed dog portion 80 is cylindrical and integrally formed with the second transmission portion 62 such that its inner peripheral wall is connected to the outer peripheral wall of the second transmission portion 62. The second fixed dog plate portion 82 is plate-shaped and extends radially outward from the outer peripheral wall of the second fixed dog cylinder portion 81. The second fixed dog teeth portion 83 protrudes from one surface of the second fixed dog plate portion 82 and is plate-shaped and extends radially. A plurality of second fixed dog teeth portions 83 are formed at equal intervals around the circumferential direction of the second fixed dog plate portion 82. A gap is formed between the second fixed dog teeth portion 83 and the outer peripheral wall of the second fixed dog cylinder portion 81.

[0096] The movable dog portion 90 has a movable dog cylindrical portion 91, a movable dog plate portion 92, a movable dog tooth portion 93, a movable dog recess 94, and a movable dog spline tooth portion 96. The movable dog cylindrical portion 91 is formed in a cylindrical shape. The movable dog plate portion 92 is formed in a plate shape so as to extend radially outward from the outer peripheral wall on one end side of the movable dog cylindrical portion 91. The movable dog spline tooth portion 96 is formed so as to extend axially while protruding radially inward from the inner peripheral wall of the movable dog cylindrical portion 91. A plurality of movable dog tooth portions 93 are formed at equal intervals around the circumferential direction of the movable dog cylindrical portion 91. Here, the number of movable dog spline tooth portions 96 formed is the same as the number of first fixed dog tooth portions 73. The movable dog tooth portions 93 are capable of meshing with the first fixed dog tooth portions 73.

[0097] The movable dog teeth portion 93 is formed in a plate shape so as to protrude from one surface of the movable dog plate portion 92 and extend in the radial direction. A plurality of movable dog teeth portions 93 are formed at equal intervals in the circumferential direction of the movable dog plate portion 92. The number of movable dog teeth portions 93 formed is the same as the number of second fixed dog teeth portions 83. The movable dog teeth portions 93 are capable of meshing with the second fixed dog teeth portions 83. The movable dog recess 94 is formed in an annular shape so as to be recessed radially inward from the outer peripheral wall of the movable dog cylindrical portion 91.

[0098] The movable dog portion 90 is provided radially outward of the first fixed dog portion 70 so that the movable dog spline teeth portion 96 can mesh with the first fixed dog teeth portion 73 and move axially relative to the first fixed dog portion 70. The movable dog portion 90 can move toward the second fixed dog portion 80, so that the movable dog teeth portion 93 can mesh with the second fixed dog teeth portion 83.

[0099] The first stopper portion 74 is formed on the movable dog portion 90 side of the first fixed dog protrusion portion 72 .

[0100] The first movable dog end portion 901 corresponds to the inner edge portion of the movable dog portion 90 , particularly the end portion of the movable dog cylindrical portion 91 opposite to the second fixed dog portion 80 .

[0101] A second stopper portion 84 is formed on the inner edge of the second fixed dog plate portion 82 on the surface facing the movable dog portion 90 .

[0102] When the first movable dog end 901 abuts against the first stopper portion 74, the movable dog portion 90 is restricted from moving in the opposite direction from the second fixed dog portion 80. When the second movable dog end 902, which is the end of the movable dog portion 90 opposite to the first movable dog end 901, abuts against the second stopper portion 84, the movable dog portion 90 is restricted from moving toward the second fixed dog portion 80. In this way, the movable dog portion 90 is capable of reciprocating axially between the first stopper portion 74 and the second stopper portion 84.

[0103] The first fixed dog portion 70 , the second fixed dog portion 80 , and the movable dog portion 90 constitute a clutch portion 700 .

[0104] When the movable dog portion 90 moves toward the second fixed dog portion 80 relative to the first fixed dog portion 70, the movable dog teeth portion 93 can mesh with the second fixed dog teeth portion 83. When the movable dog teeth portion 93 and the second fixed dog teeth portion 83 are in mesh with each other, i.e., when the clutch portion 700 is in an engaged state, torque transmission between the first transmission portion 61 and the second transmission portion 62 is permitted. On the other hand, when the movable dog teeth portion 93 and the second fixed dog teeth portion 83 are not in mesh with each other, i.e., when the clutch portion 700 is in a disengaged state, torque transmission between the first transmission portion 61 and the second transmission portion 62 is blocked.

[0105] The fork engagement member 55 of the fork 50 engages with the movable dog recess 94 of the movable dog portion 90. As a result, when the fork 50 swings, the movable dog portion 90 moves axially relative to the first fixed dog portion 70 and the first transmission portion 61.

[0106] The first stopper portion 74 is tapered so as to approach the axis Ax1 of the first fixed dog portion 70 from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 (see FIG. 8).

[0107] In this embodiment, the first movable dog end portion 901 of the movable dog portion 90 is formed in an angular shape.

[0108] The ECU 100 can control the amount of protrusion of the solenoid shaft 36 from the solenoid case 351 by controlling the power supplied to the electromagnetic coil of the solenoid 35. In the initial state where no current is applied to the electromagnetic coil of the solenoid 35, the amount of protrusion of the solenoid shaft 36 from the solenoid case 351 is smallest. At this time, the movable dog portion 90 is located radially outward of the first fixed dog portion 70 and is not engaged with the second fixed dog portion 80 (see FIG. 8). The position of the movable dog portion 90 at this time is referred to as the "release position."

[0109] In the initial state, when the amount of protrusion of the solenoid shaft 36 from the solenoid case 351 increases under the control of the ECU 100, the fork 50 swings so that the fork base 51 moves away from the solenoid case 351. As a result, the movable dog 90 translates toward the second fixed dog 80, the movable dog teeth 93 mesh with the second fixed dog teeth 83, and the clutch unit 700 enters an engaged state. The position of the movable dog 90 at this time is referred to as the "engaged position."

[0110] When the clutch unit 700 is in an engaged state, the amount of protrusion of the solenoid shaft 36 from the solenoid case 351 is reduced under the control of the ECU 100, causing the fork 50 to swing so that the fork base 51 approaches the solenoid case 351. This causes the movable dog 90 to translate in the direction opposite the second fixed dog 80, disengaging the movable dog tooth 93 from the second fixed dog tooth 83, and the clutch unit 700 enters a disengaged state.

[0111] In this embodiment, the phase difference detection unit 101 is provided in the first case 21 so as to be located radially outward of the movable dog plate portion 92 and the second fixed dog plate portion 82 (see FIG. 8 ). A magnetic circuit is disposed in the phase difference detection unit 101 so as to straddle the movable dog tooth portion 93 and the second fixed dog tooth portion 83. The phase difference detection unit 101 has a magnetic detection element capable of detecting a change in the direction (angle) of magnetic flux density generated from the yoke end of the magnetic circuit due to rotation of the movable dog portion 90 on which the movable dog tooth portion 93 is formed and the second fixed dog portion 80 on which the second fixed dog tooth portion 83 is formed. The phase difference detection unit 101 can detect a rotational phase difference between the movable dog portion 90 and the first transmission unit 61 and the second fixed dog portion 80 and the second transmission unit 62 based on the change in the direction (angle) of magnetic flux density detected by the magnetic detection element.

[0112] As in the first embodiment, the ECU 100 can control the operation of the actuator 300 based on the rotational phase difference detected by the phase difference detection unit 101. More specifically, the ECU 100 can predict the timing at which the movable dog teeth portion 93 and the second fixed dog teeth portion 83 can mesh without collision and complete the engagement operation based on the rotational phase difference detected by the phase difference detection unit 101, and can control the operation of the motor 30 to move the movable dog teeth portion 90 from the "disengaged position" to the "engaged position" in one go at that timing. This makes it possible to avoid collision between the movable dog teeth portion 93 and the second fixed dog teeth portion 83 and shorten the time until the engagement is completed.

[0113] As described above, in this embodiment, the first stopper portion 74 is formed in a tapered shape. Therefore, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axis Ax1 of the first fixed dog portion 70 and the axis Ax2 of the movable dog portion 90 substantially coincide with each other.

[0114] As in the first embodiment, the ECU 100 can control the operation of the actuator 300 so that the first movable dog end portion 901 is pressed against the first stopper portion 74 .

[0115] Third Embodiment A part of a clutch device according to a third embodiment is shown in Fig. 10. The third embodiment differs from the first embodiment in the configuration of a first stopper portion 74 and the like.

[0116] In this embodiment, the first stopper portion 74 is formed with a rounded corner so as to approach the axis Ax1 of the first fixed dog portion 70 from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 (see FIG. 10 ). In other words, the reduction rate of the outer diameter of the first stopper portion 74 changes from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80.

[0117] In this embodiment, the first movable dog end portion 901 of the movable dog portion 90 is formed in an angular shape.

[0118] In this embodiment as well, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axes of the first fixed dog portion 70 and the movable dog portion 90 substantially coincide with each other. This reduces axial misalignment between the movable dog portion 90 and the first fixed dog portion 70 and the second fixed dog portion 80. Therefore, the clutch device 10 can be controlled with high precision.

[0119] (Fourth embodiment) A part of a clutch device according to a fourth embodiment is shown in Fig. 11. The fourth embodiment differs from the first embodiment in the configuration of a first movable dog end portion 901 and the like.

[0120] In this embodiment, the angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is different from the angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90 (see FIG. 11 ). More specifically, the angle θ1 is 45 degrees, and the angle θ2 is greater than 45 degrees. That is, θ1<θ2.

[0121] Since the angle θ1 and the angle θ2 are different, the degree of freedom in determining the location where the shape of the member is set and the shape itself can be improved, and the advantageous shape and position can be selected depending on the processing method and process.

[0122] In this embodiment as well, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axes of the first fixed dog portion 70 and the movable dog portion 90 substantially coincide with each other. This reduces axial misalignment between the movable dog portion 90 and the first fixed dog portion 70 and the second fixed dog portion 80. Therefore, the clutch device 10 can be controlled with high precision.

[0123] Fifth Embodiment A part of a clutch device according to a fifth embodiment is shown in Fig. 12. The fifth embodiment differs from the fourth embodiment in the configuration of a first movable dog end portion 901 and the like.

[0124] In this embodiment, the angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is different from the angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90 (see FIG. 12 ). More specifically, the angle θ1 is smaller than 45 degrees, and the angle θ2 is also smaller than 45 degrees. Here, θ1<θ2.

[0125] Sixth Embodiment A part of a clutch device according to a sixth embodiment is shown in Fig. 13. The sixth embodiment differs from the fourth embodiment in the configuration of a first movable dog end portion 901 and the like.

[0126] In this embodiment, the angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is different from the angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90 (see FIG. 13 ). More specifically, the angle θ1 is greater than 45 degrees, and the angle θ2 is also greater than 45 degrees. Here, θ1>θ2.

[0127] Seventh Embodiment A part of a clutch device according to a seventh embodiment is shown in Fig. 14. The seventh embodiment differs from the fourth embodiment in the configuration of a first movable dog end portion 901 and the like.

[0128] In this embodiment, the angle θ1 of the first stopper portion 74 relative to the axis Ax1 of the first fixed dog portion 70 is different from the angle θ2 of the first movable dog end portion 901 relative to the axis Ax2 of the movable dog portion 90 (see FIG. 14 ). More specifically, the angle θ1 is 45 degrees, and the angle θ2 is less than 45 degrees. That is, θ1 > θ2.

[0129] Eighth Embodiment A part of a clutch device according to an eighth embodiment is shown in Fig. 15. The eighth embodiment differs from the first embodiment in the configuration of a first stopper portion 74 and the like.

[0130] In this embodiment, the first movable dog end 901 is tapered so as to approach the axis Ax2 of the movable dog portion 90 as it moves from the side opposite the second fixed dog portion 80 toward the second fixed dog portion 80 (see Figure 15).

[0131] In this embodiment, the outer edge of the end of the first fixed dog protrusion 72 on the second fixed dog 80 side is formed in an angular shape.

[0132] In this embodiment, by tapering only the first movable dog end 901 out of the first stopper portion 74 and the first movable dog end 901, the number of processing steps can be reduced, and the cost of the clutch device 10 can be reduced.

[0133] In this embodiment as well, when the movable dog portion 90 moves toward the first stopper portion 74 and the first movable dog end portion 901 abuts against the first stopper portion 74, the movable dog portion 90 is aligned with the first fixed dog portion 70 so that the axes of the first fixed dog portion 70 and the movable dog portion 90 substantially coincide with each other. This reduces axial misalignment between the movable dog portion 90 and the first fixed dog portion 70 and the second fixed dog portion 80. Therefore, the clutch device 10 can be controlled with high precision.

[0134] Ninth Embodiment A part of a clutch device according to a ninth embodiment is shown in Fig. 16. The ninth embodiment differs from the eighth embodiment in the configuration of a first movable dog end portion 901 and the like.

[0135] In this embodiment, the first movable dog end 901 is formed with rounded corners so as to approach the axis Ax2 of the movable dog 90 from the side opposite to the second fixed dog 80 toward the second fixed dog 80 (see FIG. 16 ). In other words, the reduction rate of the inner diameter of the first movable dog end 901 changes from the side opposite to the second fixed dog 80 toward the second fixed dog 80.

[0136] Other Embodiments In other embodiments, the control unit does not have to be able to control the operation of the actuator so that the end of the movable dog is pressed against the stopper portion.

[0137] In other embodiments, the clutch device may not include a phase difference detector and a controller.

[0138] In the above-described embodiment, the clutch device 10 is provided between the differential shaft 11 and the wheel shafts 12 to control the transmission of torque between the differential shaft 11 and the wheel shafts 12. However, in another embodiment, the clutch device 10 may be applied by dividing the first gear shaft 3 into two shafts between the motor generator 2 and the first small-diameter gear 5, with one shaft connected to the first transmission section 61 and the other shaft connected to the second transmission section 62. In this case, the clutch device 10 can control the transmission of torque between the motor generator 2 and the first small-diameter gear 5.

[0139] In another embodiment, the clutch device 10 may be applied by dividing the second gear shaft 4 into two parts between the first large diameter gear 6 and the second small diameter gear 7, with one part connected to the first transmission part 61 and the other part connected to the second transmission part 62. In this case, the clutch device 10 can control the transmission of torque between the first large diameter gear 6 and the second small diameter gear 7.

[0140] In addition, in the above-described embodiment, an example has been shown in which the clutch device is used to control the transmission of torque between the motor generator and the rear wheels of the vehicle. However, in other embodiments, the clutch device may be used to control the transmission of torque between the motor generator and the front wheels of the vehicle.

[0141] Furthermore, the present disclosure is not limited to electric vehicles, but can also be applied to vehicles that run on drive torque from an internal combustion engine, hybrid vehicles, and the like.

[0142] As such, the present disclosure is not limited to the above-described embodiments, and can be implemented in various forms without departing from the spirit of the present disclosure.

[0143] The present disclosure has been described based on the embodiments. However, the present disclosure is not limited to the embodiments and structures. The present disclosure also encompasses various modifications and variations within the scope of equivalents. Furthermore, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

Claims

1. An actuator (300) capable of outputting power when energized; a first transmission part (61); a second transmission part (62) rotatable relative to the first transmission part; a first fixed dog part (70) provided so as to be rotatable integrally with the first transmission part; a second fixed dog part (80) provided so as to face the first fixed dog part in the axial direction so as to be rotatable integrally with the second transmission part; and a movable dog part (90) which is not rotatable relative to the first fixed dog part but is provided so as to be movable relative to the axial direction, moves relative to the first fixed dog part in the axial direction by power output from the actuator, and when engaged with the second fixed dog part, allows transmission of torque between the first transmission part and the second transmission part. a stopper portion (74) that is provided on the first fixed dog portion and that can restrict movement of the movable dog portion to the opposite side from the second fixed dog portion by abutting against a movable dog end portion (901) that is one axial end of the movable dog portion, wherein the stopper portion is formed in a tapered shape or a corner R shape so as to approach the axis of the first fixed dog portion as it moves from the opposite side from the second fixed dog portion toward the second fixed dog portion.

2. An actuator (300) capable of outputting power when energized; a first transmission part (61); a second transmission part (62) rotatable relative to the first transmission part; a first fixed dog part (70) provided so as to be rotatable integrally with the first transmission part; a second fixed dog part (80) provided so as to face the first fixed dog part in the axial direction so as to be rotatable integrally with the second transmission part; and a movable dog part (90) which is not rotatable relative to the first fixed dog part but is provided so as to be movable relative to the axial direction, moves relative to the first fixed dog part in the axial direction by the power output from the actuator, and when meshed with the second fixed dog part, allows transmission of torque between the first transmission part and the second transmission part. a stopper portion (74) that is provided on the first fixed dog portion and that can restrict movement of the movable dog portion toward the opposite side from the second fixed dog portion by abutting against a movable dog end portion (901) that is one axial end portion of the movable dog portion, wherein the movable dog end portion is formed in a tapered shape or a corner R shape so as to approach the axis of the movable dog portion as it moves from the opposite side to the second fixed dog portion toward the second fixed dog portion.

3. A clutch device according to claim 1, wherein the movable dog end is tapered so as to approach the axis of the movable dog as it moves from the side opposite the second fixed dog toward the second fixed dog.

4. A clutch device as described in claim 3, wherein the stopper portion and the movable dog end portion are formed in a tapered shape, and the angle (θ1) of the stopper portion relative to the axis (Ax1) of the first fixed dog portion is the same as the angle (θ2) of the movable dog end portion relative to the axis (Ax2) of the movable dog portion.

5. A clutch device as described in claim 3, wherein the stopper portion and the movable dog end portion are formed in a tapered shape, and the angle (θ1) of the stopper portion relative to the axis (Ax1) of the first fixed dog portion is different from the angle (θ2) of the movable dog end portion relative to the axis (Ax2) of the movable dog portion.

6. A clutch device according to any one of claims 1 to 5, further comprising: a phase difference detection unit (101) capable of detecting the rotational phase difference between the movable dog portion and the second fixed dog portion; and a control unit (100) capable of controlling the operation of the actuator based on the rotational phase difference detected by the phase difference detection unit.

7. The clutch device according to claim 6, wherein the control unit is capable of controlling the operation of the actuator so that the end of the movable dog is pressed against the stopper portion.

Images