Engagement device

Abstract

A clutch mechanism (1) comprises: a first frictional engagement element (11) which rotates integrally with a first rotary member (81); and a second frictional engagement element (12) which rotates integrally with a second rotary member (82). A brake mechanism (2) comprises: a third frictional engagement element (21) for rotating integrally with a target rotary member (8T), which is either one of the rotary members (81, 82); and a fourth frictional engagement element (22) which is fixed to a non-rotary member (NR). A pressing mechanism (3) comprises: a pressing part (31) which is disposed between the frictional engagement elements (11, 12) and the frictional engagement elements (21, 22) in the axial direction (L); a driven part (32) which is coupled to the pressing part (31) so as to operate simultaneously therewith; and a linear motion mechanism (33) which moves the driven part (32) in the axial direction (L). The clutch mechanism (1) and the brake mechanism (2) are selectively engaged depending on whether the driven part (32) is moved toward a first axial side (L1) or a second axial side (L2) by the linear motion mechanism (33).

Description

[Technical field]

[0001] The present invention relates to an engagement device including a clutch mechanism and a brake mechanism. [Background technology]

[0002] An example of such an engagement device is disclosed in the following Patent Document 1. In the following description of the background art, the reference symbols in Patent Document 1 will be cited in parentheses.

[0003] The engagement device (3) disclosed in Patent Document 1 includes a clutch mechanism (31) that selectively engages a first rotating member (33) and a second rotating member (34), and a brake mechanism (32) that selectively engages the first rotating member (33) with a non-rotating member (35).

[0004] The clutch mechanism (31) includes a first friction engagement element (31b) connected to the first rotating member (33) so as to rotate integrally with it, and a second friction engagement element (31a) connected to the second rotating member (34) so ​​as to rotate integrally with it. The brake mechanism (32) includes a third friction engagement element (32a) connected to the first rotating member (33) so as to rotate integrally with it, and a fourth friction engagement element (32b) fixed to a non-rotating member (35). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-197846 A Summary of the Invention [Problem to be solved by the invention]

[0006] The engagement device (3) disclosed in Patent Document 1 includes a first pressing mechanism (72) that presses the first friction engagement element (31b) and the second friction engagement element (31a) of the clutch mechanism (31) in the axial direction (the left-right direction in Figure 2 of Patent Document 1), and a second pressing mechanism (77) that presses the third friction engagement element (32a) and the fourth friction engagement element (32b) of the brake mechanism (32) in the axial direction.

[0007] The clutch mechanism (31) and the brake mechanism (32) are arranged side by side in the radial direction (the up-down direction in FIG. 2 of Patent Document 1). The first pressing mechanism (72) is arranged on one axial side (the right side in FIG. 2 of Patent Document 1) of the clutch mechanism (31). The second pressing mechanism (77) is arranged on the other axial side (the right side in FIG. 2 of Patent Document 1) of the brake mechanism (32). This configuration leads to an increase in size of the engagement device (3).

[0008] Therefore, it is desirable to realize an engagement device that can be made smaller in size in a configuration that includes a clutch mechanism and a brake mechanism. [Means for solving the problem]

[0009] In view of the above, the characteristic configuration of the engagement device is as follows: a clutch mechanism that selectively engages the first rotating member and the second rotating member; a brake mechanism that selectively engages a target rotating member, which is one of the first rotating member and the second rotating member, with a non-rotating member, a pressing mechanism for changing an engagement state of the clutch mechanism and the brake mechanism, A direction along the rotation axis of the first rotating member is defined as an axial direction, one side in the axial direction is defined as an axial first side, and the other side in the axial direction is defined as an axial second side, the clutch mechanism includes a first friction engagement element connected to the first rotating member so as to rotate integrally with the first rotating member, and a second friction engagement element connected to the second rotating member so as to rotate integrally with the second rotating member, the first friction engagement element and the second friction engagement element are disposed to face each other in the axial direction and are frictionally engaged with each other by being pressed against each other in the axial direction; the brake mechanism includes a third friction engagement element connected to the target rotating member so as to rotate integrally with the target rotating member, and a fourth friction engagement element fixed to the non-rotating member, the third friction engagement element and the fourth friction engagement element are disposed to face each other in the axial direction at positions spaced apart from the first friction engagement element and the second friction engagement element on the second axial direction side, and are pressed against each other in the axial direction to frictionally engage with each other, the pressing mechanism includes a pressing portion disposed between the first friction engagement element and the second friction engagement element and the third friction engagement element and the fourth friction engagement element in the axial direction, a driven portion connected to be interlocked with the pressing portion, and a linear motion mechanism that moves the driven portion in the axial direction, the first rotating member, the second rotating member, the first frictional engagement element, the second frictional engagement element, the third frictional engagement element, and the fourth frictional engagement element are coaxially arranged, The clutch mechanism and the brake mechanism are selectively engaged in response to the driven part being moved toward the first axial side or the second axial side by the linear motion mechanism.

[0010] According to this characteristic configuration, the pressing portion, which moves in the axial direction via the driven portion by the linear motion mechanism, is disposed between the first and second frictional engagement elements and the third and fourth frictional engagement elements disposed on the second axial side relative to them. Then, when the driven portion moves to the first axial side by the linear motion mechanism, the first and second frictional engagement elements are pressed by the pressing portion, and the clutch mechanism is brought into an engaged state, and the pressing of the third and fourth frictional engagement elements by the pressing portion is released, and the brake mechanism is brought into a released state. On the other hand, when the driven portion moves to the second axial side by the linear motion mechanism, the third and fourth frictional engagement elements are pressed by the pressing portion, and the brake mechanism is brought into an engaged state, and the pressing of the first and second frictional engagement elements by the pressing portion is released, and the clutch mechanism is brought into a released state. This allows the engagement state of the clutch mechanism and the brake mechanism to be changed by a common pressing mechanism. Therefore, in a configuration including a clutch mechanism and a brake mechanism, the engagement device can be made smaller. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a cross-sectional view taken along an axial direction of the engagement device according to the first embodiment; [Diagram 2] FIG. 2 is a partially enlarged cross-sectional view of the engagement device according to the first embodiment taken along an axial direction; [Diagram 3] FIG. 11 is a cross-sectional view of an engagement device according to a second embodiment taken along an axial direction. [Figure 4] FIG. 13 is a partially enlarged cross-sectional view of an engagement device according to a second embodiment taken along an axial direction; [Diagram 5] 1 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a first embodiment; [Figure 6] FIG. 1 is a skeleton diagram of a vehicle drive device according to a first embodiment; [Figure 7] 1 is a speed diagram of a planetary gear mechanism of a vehicle drive device according to a first embodiment of the present invention; [Figure 8] FIG. 11 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a second embodiment; [Figure 9] 1 is a skeleton diagram of a vehicle drive device according to a second embodiment; [Figure 10] FIG. 11 is a cross-sectional view taken along an axial direction of a vehicle drive device according to a third embodiment; [Figure 11] FIG. 13 is a skeleton diagram of a vehicle drive device according to a third embodiment; [Figure 12] FIG. 11 is a partially enlarged cross-sectional view of a dual-purpose drive device according to a third embodiment taken along an axial direction; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] 1. Engagement device according to the first embodiment An engagement device 100 according to a first embodiment will be described below with reference to the drawings. As shown in Fig. 1, the engagement device 100 includes a clutch mechanism 1 that selectively engages a first rotating member 81 with a second rotating member 82, a brake mechanism 2 that selectively engages a target rotating member 8T, which is either the first rotating member 81 or the second rotating member 82, with a non-rotating member NR, and a pressing mechanism 3 that changes the engagement state of the clutch mechanism 1 and the brake mechanism 2.

[0013] The first rotating member 81 and the second rotating member 82 are supported so as to be rotatable relative to each other. In the following description, the direction along the rotation axis of the first rotating member 81 is referred to as the "axial direction L". One side of the axial direction L is referred to as the "first axial side L1", and the other side is referred to as the "second axial side L2". In addition, the direction perpendicular to the rotation axis of the rotating members such as the first rotating member 81 is referred to as the "radial direction R" based on each rotation axis. Note that when it is not necessary to distinguish which rotation axis is used as the reference or when it is clear which rotation axis is used as the reference, it may be simply referred to as the "radial direction R".

[0014] In this embodiment, the non-rotating member NR is a case 9 that houses the engagement device 100. In this embodiment, the case 9 includes a first circumferential wall portion 91, a first side wall portion 92, a support wall portion 93, and a cover portion 94.

[0015] The first peripheral wall portion 91 is formed so as to cover the outer sides of the first rotating member 81 and the second rotating member 82 in the radial direction R. The first side wall portion 92 is formed so as to cover a first axial side L1 of the first rotating member 81 and the second rotating member 82. The support wall portion 93 is formed so as to cover a second axial side L2 of the first rotating member 81 and the second rotating member 82. The cover portion 94 is formed so as to cover the second axial side L2 of the support wall portion 93.

[0016] In this embodiment, the first peripheral wall portion 91 is formed in a cylindrical shape having an axis along the axial direction L. An opening on the first axial side L1 of the first peripheral wall portion 91 is blocked by a first side wall portion 92. An opening on the second axial side L2 of the first peripheral wall portion 91 is blocked by a support wall portion 93. In this example, the first peripheral wall portion 91 and the first side wall portion 92 are integrally formed to constitute a first case portion 9A. A second case portion 9B including the support wall portion 93 is fitted into the first case portion 9A from the first axial side L1 so that the support wall portion 93 is located on the inside in the radial direction R with respect to the first peripheral wall portion 91. A third case portion 9C including a cover portion 94 is joined to the second case portion 9B from the first axial side L1.

[0017] The clutch mechanism 1 includes a first friction engagement element 11 connected to a first rotating member 81 so as to rotate integrally with the first rotating member 81, and a second friction engagement element 12 connected to a second rotating member 82 so as to rotate integrally with the second rotating member 82.

[0018] The first friction engagement element 11 and the second friction engagement element 12 are disposed so as to face each other in the axial direction L. The first friction engagement element 11 and the second friction engagement element 12 are frictionally engaged with each other by being pressed in the axial direction L. In this embodiment, the first friction engagement element 11 and the second friction engagement element 12 are provided in multiple pieces and are disposed alternately along the axial direction L. Either the first friction engagement element 11 or the second friction engagement element 12 can be a friction plate, and the other can be a separate plate.

[0019] The brake mechanism 2 includes a third friction engagement element 21 connected to the target rotating member 8T so as to rotate integrally with the target rotating member 8T, and a fourth friction engagement element 22 fixed to the non-rotating member NR. In this embodiment, the first rotating member 81 is the target rotating member 8T.

[0020] The third friction engagement element 21 and the fourth friction engagement element 22 are disposed so as to face each other in the axial direction L. The third friction engagement element 21 and the fourth friction engagement element 22 are frictionally engaged with each other by being pressed in the axial direction L. The third friction engagement element 21 and the fourth friction engagement element 22 are disposed so as to be spaced apart from each other on the second axial side L2 with respect to the first friction engagement element 11 and the second friction engagement element 12. In this embodiment, the third friction engagement element 21 and the fourth friction engagement element 22 are provided in multiple pieces, and are disposed alternately along the axial direction L. One of the third friction engagement element 21 and the fourth friction engagement element 22 may be a friction plate, and the other may be a separate plate.

[0021] The first rotating member 81, the second rotating member 82, the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22 are arranged on a first axis X1. In other words, the first rotating member 81, the second rotating member 82, the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22 are arranged coaxially.

[0022] As shown in Fig. 2, in this embodiment, the first rotating member 81 has a first connecting portion 8a to which the first frictional engagement element 11 is connected. The second rotating member 82 has a second connecting portion 8b to which the second frictional engagement element 12 is connected. The target rotating member 8T has a third connecting portion 8c to which the third frictional engagement element 21 is connected. That is, in this embodiment, the first rotating member 81 has the third connecting portion 8c. The non-rotating member NR has a fourth connecting portion 8d to which the fourth frictional engagement element 22 is connected.

[0023] The first connecting portion 8a is disposed at a position that is outside the first friction engagement element 11 in the radial direction R and overlaps with the first friction engagement element 11 as viewed in the radial direction along the radial direction R. That is, the first friction engagement element 11 is supported from the outside in the radial direction R by the first connecting portion 8a. The first friction engagement element 11 is supported so as to be slidable in the axial direction L in a state in which relative rotation is restricted with respect to the first connecting portion 8a. In this example, a plurality of spline grooves extending in the axial direction L are formed in a circumferentially distributed manner on the outer periphery of the first friction engagement element 11. On the other hand, similar spline grooves are also formed in a circumferentially distributed manner on the inner periphery of the first connecting portion 8a. These spline grooves are engaged with each other. Here, with regard to the arrangement of two elements, "overlapping as viewed in a specific direction" refers to the existence of at least a part of an area in which a virtual straight line parallel to the line of sight intersects with both of the two elements when the virtual straight line is moved in each direction perpendicular to the virtual straight line.

[0024] The second connecting portion 8b is disposed on the inside of the second friction engagement element 12 in the radial direction R, and is positioned so as to overlap the second friction engagement element 12 and the first connecting portion 8a when viewed in the radial direction along the radial direction R. That is, the second friction engagement element 12 is supported from the inside of the radial direction R by the second connecting portion 8b. The second friction engagement element 12 is supported so as to be slidable in the axial direction L in a state in which relative rotation is restricted with respect to the second connecting portion 8b. In this example, a plurality of spline grooves extending in the axial direction L are formed in the inner peripheral portion of the second friction engagement element 12 in a circumferentially distributed manner. On the other hand, similar spline grooves are also formed in the outer peripheral portion of the second connecting portion 8b in a circumferentially distributed manner. These spline grooves are engaged with each other.

[0025] The third connecting portion 8c is disposed at a position that is outside the third frictional engagement element 21 in the radial direction R and overlaps with the third frictional engagement element 21 as viewed in the radial direction R. That is, the third frictional engagement element 21 is supported from the outside in the radial direction R by the third connecting portion 8c. The third frictional engagement element 21 is supported so as to be slidable in the axial direction L in a state in which relative rotation is restricted with respect to the third connecting portion 8c. In this example, a plurality of spline grooves extending in the axial direction L are formed in a circumferentially distributed manner on the outer periphery of the third frictional engagement element 21. On the other hand, similar spline grooves are also formed in a circumferentially distributed manner on the inner periphery of the third connecting portion 8c. These spline grooves are engaged with each other.

[0026] The fourth connecting portion 8d is disposed on the inner side of the fourth friction engagement element 22 in the radial direction R, and is arranged at a position overlapping with the fourth friction engagement element 22 and the third connecting portion 8c as viewed in the radial direction R. That is, the fourth friction engagement element 22 is supported from the inner side in the radial direction R by the fourth connecting portion 8d. The fourth friction engagement element 22 is supported so as to be slidable in the axial direction L in a state in which relative rotation is restricted with respect to the fourth connecting portion 8d. In this example, a plurality of spline grooves extending in the axial direction L are formed in the inner peripheral portion of the fourth friction engagement element 22 in a circumferentially distributed manner. On the other hand, similar spline grooves are also formed in the outer peripheral portion of the fourth connecting portion 8d in a circumferentially distributed manner. These spline grooves are engaged with each other.

[0027] As shown in FIG. 2, in this embodiment, the first rotating member 81 includes a first outer support portion 811 and a first radially extending portion 812.

[0028] The first outer support portion 811 is formed in a cylindrical shape with the first axis X1 as its axis. In this embodiment, the first outer support portion 811 is provided with the first connecting portion 8a and the third connecting portion 8c.

[0029] The first radial extending portion 812 is formed to extend along a radial direction R based on the first axis X1. In this embodiment, the first radial extending portion 812 is formed to extend inward in the radial direction R from an end portion of the first outer support portion 811 on the axial first side L1. In this embodiment, the first radial extending portion 812 is rotatably supported by the first side wall portion 92 of the case 9 via a first bearing B1. In this example, the first bearing B1 is a thrust bearing disposed between the first radial extending portion 812 and the first side wall portion 92 in the axial direction L.

[0030] In this embodiment, the second rotating member 82 includes a first inner support portion 821. The first inner support portion 821 is disposed on the inside in the radial direction R with respect to the first outer support portion 811. In this embodiment, the second connecting portion 8b is disposed on the first inner support portion 821.

[0031] In this embodiment, the support wall portion 93 of the case 9 includes a second inner support portion 931. The second inner support portion 931 is disposed on the inside in the radial direction R with respect to the first outer support portion 811. In this embodiment, the second inner support portion 931 is formed in a cylindrical shape with the first axis X1 as its axis. In this embodiment, the fourth connecting portion 8d is disposed in the second inner support portion 931.

[0032] The pressing mechanism 3 includes a pressing portion 31 arranged between the first frictional engagement element 11 and the second frictional engagement element 12, and the third frictional engagement element 21 and the fourth frictional engagement element 22, in the axial direction L, a driven portion 32 connected to interlock with the pressing portion 31, and a linear motion mechanism 33 that moves the driven portion 32 in the axial direction L.

[0033] When the driven part 32 moves to the first axial side L1 by the linear motion mechanism 33, the first frictional engagement element 11 and the second frictional engagement element 12 are pressed by the pressing part 31, so that the clutch mechanism 1 is in an engaged state, and the pressing of the third frictional engagement element 21 and the fourth frictional engagement element 22 by the pressing part 31 is released, so that the brake mechanism 2 is in a released state. On the other hand, when the driven part 32 moves to the second axial side L2 by the linear motion mechanism 33, the third frictional engagement element 21 and the fourth frictional engagement element 22 are pressed by the pressing part 31, so that the brake mechanism 2 is in an engaged state, and the pressing of the first frictional engagement element 11 and the second frictional engagement element 12 by the pressing part 31 is released, so that the clutch mechanism 1 is in a released state. In this way, the clutch mechanism 1 and the brake mechanism 2 are selectively engaged depending on whether the driven part 32 moves to the first axial side L1 or the second axial side L2 by the linear motion mechanism 33.

[0034] As described above, the engagement device 100 has the following features: a clutch mechanism 1 that selectively engages a first rotating member 81 and a second rotating member 82; An engagement device 100 including a brake mechanism 2 that selectively engages a target rotating member 8T, which is either a first rotating member 81 or a second rotating member 82, with a non-rotating member NR, A pressing mechanism 3 is provided for changing the engagement state of the clutch mechanism 1 and the brake mechanism 2. The clutch mechanism 1 includes a first friction engagement element 11 connected to a first rotating member 81 so as to rotate integrally with the first friction engagement element 11, and a second friction engagement element 12 connected to a second rotating member 82 so as to rotate integrally with the second friction engagement element 12. The first frictional engagement element 11 and the second frictional engagement element 12 are disposed to face each other in the axial direction L, and are frictionally engaged with each other by being pressed in the axial direction L. The brake mechanism 2 includes a third friction engagement element 21 connected to the target rotating member 8T so as to rotate integrally with the target rotating member 8T, and a fourth friction engagement element 22 fixed to a non-rotating member NR. The third friction engagement element 21 and the fourth friction engagement element 22 are disposed to face each other in the axial direction L at positions spaced apart on the axial second side L2 from the first friction engagement element 11 and the second friction engagement element 12, and are frictionally engaged with each other by being pressed in the axial direction L. The pressing mechanism 3 includes a pressing portion 31 disposed between the first frictional engagement element 11 and the second frictional engagement element 12 and the third frictional engagement element 21 and the fourth frictional engagement element 22 in an axial direction L, a driven portion 32 connected to the pressing portion 31 so as to move in conjunction with the pressing portion 31, and a linear motion mechanism 33 that moves the driven portion 32 in the axial direction L, A first rotating member 81, a second rotating member 82, a first frictional engagement element 11, a second frictional engagement element 12, a third frictional engagement element 21, and a fourth frictional engagement element 22 are coaxially arranged, In response to the driven part 32 being moved by the linear motion mechanism 33 to the first axial side L1 or to the second axial side L2, the clutch mechanism 1 and the brake mechanism 2 are selectively engaged.

[0035] According to this configuration, the pressing portion 31, which is moved in the axial direction L via the driven portion 32 by the linear motion mechanism 33, is disposed between the first frictional engagement element 11 and the second frictional engagement element 12 and the third frictional engagement element 21 and the fourth frictional engagement element 22, which are disposed on the second axial side L2 relative to the first frictional engagement element 11 and the second frictional engagement element 12. Then, as the driven portion 32 moves to the first axial side L1 by the linear motion mechanism 33, the first frictional engagement element 11 and the second frictional engagement element 12 are pressed by the pressing portion 31, so that the clutch mechanism 1 is brought into an engaged state, and at the same time, the pressing of the third frictional engagement element 21 and the fourth frictional engagement element 22 by the pressing portion 31 is released, so that the brake mechanism 2 is brought into a released state. On the other hand, when the driven part 32 is moved to the second axial side L2 by the linear motion mechanism 33, the third friction engagement element 21 and the fourth friction engagement element 22 are pressed by the pressing part 31, and the brake mechanism 2 is brought into an engaged state, and the pressing of the first friction engagement element 11 and the second friction engagement element 12 by the pressing part 31 is released, and the clutch mechanism 1 is brought into a released state. This makes it possible to change the engagement state of the clutch mechanism 1 and the brake mechanism 2 by the common pressing mechanism 3. Therefore, in a configuration including the clutch mechanism 1 and the brake mechanism 2, it is possible to reduce the size of the engagement device 100.

[0036] In this embodiment, the linear motion mechanism 33 includes a screw shaft 331 rotatably supported by a non-rotating member NR, and a nut member 332 that screws onto the screw shaft 331.

[0037] A screw thread is formed on the outer periphery of the screw shaft 331. The screw shaft 331 is formed to extend along the axial direction L. In this embodiment, the screw shaft 331 is disposed on the first axis X1.

[0038] A groove that engages with the thread of the screw shaft 331 is formed on the inner periphery of the nut member 332. When the screw shaft 331 rotates, the nut member 332 performs linear motion along the axial direction L according to the direction of rotation and the orientation of the thread of the screw shaft 331. In this embodiment, the nut member 332 is connected to the driven part 32 so as to move in the axial direction L integrally. Therefore, in this embodiment, as the screw shaft 331 rotates, the pressing part 31 moves in the axial direction L via the nut member 332 and the driven part 32.

[0039] In this embodiment, the nut member 332 is supported in a state in which it is movable relative to the non-rotating member NR in the axial direction L and its relative rotation is restricted. In this example, the nut member 332 is disposed inside in the radial direction R with respect to the second inner support portion 931 of the support wall portion 93 in the case 9. The nut member 332 is connected to the second inner support portion 931 by a connecting member 33a disposed between an outer periphery of the nut member 332 and an inner periphery of the second inner support portion 931 in the radial direction R in a state in which it is movable relative to the case 9 in the axial direction L and its relative rotation is restricted.

[0040] In this embodiment, the linear motion mechanism 33 is disposed on the second axial side L2 with respect to the second connecting portion 8b. Furthermore, the linear motion mechanism 33 is disposed on the inner side in the radial direction R with respect to the fourth connecting portion 8d, at a position overlapping with the fourth connecting portion 8d as viewed in the radial direction along the radial direction R. In this example, the screw shaft 331 and the nut member 332 of the linear motion mechanism 33 are disposed on the second axial side L2 with respect to the first inner support portion 821 of the second rotating member 82. Furthermore, the screw shaft 331 and the nut member 332 are disposed on the inner side in the radial direction R with respect to the second inner support portion 931 of the support wall portion 93 in the case 9.

[0041] In this manner, in this embodiment, the first rotating member 81 includes the first connecting portion 8a to which the first friction engagement element 11 is connected, The second rotating member 82 includes a second connecting portion 8b to which the second friction engagement element 12 is connected. The target rotating member 8T includes a third connecting portion 8c to which the third friction engagement element 21 is connected, The non-rotating member NR includes a fourth connecting portion 8d to which the fourth friction engagement element 22 is connected, The first connecting portion 8a is disposed on the outer side of the first friction engagement element 11 in the radial direction R and at a position overlapping with the first friction engagement element 11 as viewed in the radial direction along the radial direction R, The third connecting portion 8c is disposed on the outer side of the third friction engagement element 21 in the radial direction R and at a position overlapping with the third friction engagement element 21 as viewed in the radial direction along the radial direction R, The second connecting portion 8b is disposed on the inside in the radial direction R with respect to the second friction engagement element 12, at a position overlapping with the second friction engagement element 12 and the first connecting portion 8a as viewed in the radial direction along the radial direction R, The fourth connecting portion 8d is disposed on the inner side in the radial direction R with respect to the fourth friction engagement element 22 and at a position overlapping with the fourth friction engagement element 22 and the third connecting portion 8c as viewed in the radial direction R, The linear motion mechanism 33 is arranged on the second axial side L2 relative to the second connecting portion 8b, and is arranged on the radial inside of the fourth connecting portion 8d in the radial direction R at a position overlapping with the fourth connecting portion 8d when viewed radially along the radial direction R.

[0042] According to this configuration, the linear motion mechanism 33 is disposed on the second axial side L2 with respect to the second connecting portion 8b of the second rotating member 82. This makes it possible to keep the radial dimension R of the engagement device 100 small, compared to a configuration in which the linear motion mechanism 33 is disposed so as to overlap with the second connecting portion 8b when viewed in the radial direction. Moreover, according to this configuration, the linear motion mechanism 33 is disposed on the inside in the radial direction R with respect to the fourth connecting portion 8d of the non-rotating member NR and at a position overlapping with the fourth connecting portion 8d as viewed in the radial direction along the radial direction R. This makes it possible to keep the dimension in the axial direction L of the engagement device 100 small compared to a configuration in which the linear motion mechanism 33 is disposed offset in the axial direction L from the fourth connecting portion 8d. Moreover, since the linear motion mechanism 33 disposed on the inside in the radial direction R with respect to the fourth connecting portion 8d of the non-rotating member NR can be easily supported by the non-rotating member NR, the support structure of the linear motion mechanism 33 can be easily simplified.

[0043] In this embodiment, the pressing portion 31 includes a first pressing portion 311 and a second pressing portion 312.

[0044] The first pressing portion 311 is configured to press the first friction engagement element 11 and the second friction engagement element 12 in the axial direction L. The second pressing portion 312 is configured to press the third friction engagement element 21 and the fourth friction engagement element 22 in the axial direction L. In this embodiment, the first pressing portion 311 and the second pressing portion 312 are configured by different members arranged to face each other in the axial direction L. The first pressing portion 311 and the second pressing portion 312 are supported via the fourth bearing B4 so as to be relatively rotatable with respect to each other. Therefore, in this embodiment, the first pressing portion 311 and the second pressing portion 312 are configured to move in conjunction with each other in the axial direction L in a relatively rotatable state. In this example, the fourth bearing B4 is a thrust bearing arranged between the first pressing portion 311 and the second pressing portion 312 in the axial direction L.

[0045] The first pressing portion 311 is supported in a state in which it is movable relative to the first rotating member 81 or the second rotating member 82 in the axial direction L and rotates integrally with the first rotating member 81 or the second rotating member 82. In this embodiment, the first pressing portion 311 is supported in a state in which it is movable relative to the first outer support portion 811 of the first rotating member 81 in the axial direction L and rotates integrally with the first rotating member 81. In this example, an outer end portion of the first pressing portion 311 in the radial direction R is connected to the first connecting portion 8a.

[0046] The second pressing portion 312 is supported in a state in which it is movable relative to the non-rotating member NR in the axial direction L and its relative rotation is restricted. In this embodiment, the second pressing portion 312 is connected to the driven portion 32 so as to move integrally in the axial direction L. In this example, the driven portion 32 is formed so as to extend inward in the radial direction R from the second pressing portion 312. As described above, in this embodiment, the nut member 332 is supported in a state in which it is movable relative to the non-rotating member NR in the axial direction L and its relative rotation is restricted. Therefore, in this embodiment, the second pressing portion 312 is supported in a state in which it is movable relative to the non-rotating member NR in the axial direction L and its relative rotation is restricted via the driven portion 32 and the nut member 332.

[0047] As described above, in the present embodiment, the pressing portion 31 includes a first pressing portion 311 that presses the first frictional engagement element 11 and the second frictional engagement element 12 in the axial direction L, and a second pressing portion 312 that presses the third frictional engagement element 21 and the fourth frictional engagement element 22 in the axial direction L. The first pressing portion 311 is supported in a state in which it is movable relative to the first rotating member 81 or the second rotating member 82 in the axial direction L and rotates integrally with the first rotating member 81 or the second rotating member 82. The second pressing portion 312 is supported in a state in which it is movable relative to the non-rotating member NR in the axial direction L and the relative rotation is restricted. The first pressing portion 311 and the second pressing portion 312 are configured to move in conjunction with each other in the axial direction L while being capable of rotating relative to each other. The driven portion 32 is connected to the second pressing portion 312 so as to move integrally with the second pressing portion 312 in the axial direction L.

[0048] According to this configuration, the driven part 32, which is moved in the axial direction L by the linear motion mechanism 33, is connected to the second pressing part 312, which is supported in a state in which its relative rotation is restricted with respect to the non-rotating member NR, so as to move in the axial direction L integrally. This makes it easier to simplify the pressing mechanism 3, compared to a configuration in which the driven part 32 is connected to the first pressing part 311, which is supported in a state in which it rotates integrally with the first rotating member 81 or the second rotating member 82, so as to move in the axial direction L integrally.

[0049] As described above, in this embodiment, the threaded shaft 331 is disposed on the first axis X1. That is, in this embodiment, the threaded shaft 331 is disposed coaxially with the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22. In this embodiment, the threaded shaft 331 is disposed on the inner side in the radial direction R with respect to the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22.

[0050] As described above, in this embodiment, the linear motion mechanism 33 includes the threaded shaft 331 rotatably supported by the non-rotating member NR, and the nut member 332 screwed onto the threaded shaft 331. The nut member 332 is connected to the driven portion 32 so as to move integrally with the driven portion 32 in the axial direction L. The screw shaft 331 is arranged coaxially with the first friction engagement element 11, the second friction engagement element 12, the third friction engagement element 21, and the fourth friction engagement element 22 and on the inner side in the radial direction R.

[0051] According to this configuration, the threaded shaft 331 for moving the nut member 332 in the axial direction L is disposed on the inside in the radial direction R of the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22. This makes it easy to transmit the driving force for rotationally driving the threaded shaft 331 from the outside in the axial direction L of the frictional engagement elements 11, 12, 21, and 22 to the threaded shaft 331. This makes it easy to realize a structure in which the pressing portion 31 disposed between the first frictional engagement element 11 and the second frictional engagement element 12 and the third frictional engagement element 21 and the fourth frictional engagement element 22 in the axial direction L can be moved in the axial direction L via the nut member 332 and the driven portion 32. Moreover, according to this configuration, it is easy to arrange the screw shaft 331 of the linear motion mechanism 33 so as to overlap at least a portion of the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22 when viewed in the radial direction R. This makes it possible to prevent the engagement device 100 from becoming large in the axial direction L due to the arrangement of the linear motion mechanism 33.

[0052] As shown in FIG. 1, in this embodiment, the engagement device 100 further includes a drive source 4 for rotating the screw shaft 331, and a transmission mechanism 5 for transmitting power between the drive source 4 and the screw shaft 331.

[0053] In this embodiment, the driving source 4 is disposed on a second axis X2 different from the first axis X1. That is, in this embodiment, the driving source 4 is disposed on an axis different from that of the screw shaft 331. The arrangement area of ​​the driving source 4 in the axial direction L overlaps with the arrangement area of ​​the first rotating member 81 in the axial direction L. In this embodiment, the transmission mechanism 5 is disposed on the second axial side L2 with respect to the linear motion mechanism 33.

[0054] As shown in FIG. 2, in this embodiment, the first rotating member 81 is connected to the first shaft member 10 so as to rotate integrally with the first rotating member 81. The first shaft member 10 is arranged to extend from the first rotating member 81 to the first axial side L1. In this embodiment, the first shaft member 10 is formed in a cylindrical shape with the first axis X1 as its axis. The first shaft member 10 is formed to extend from the inner end of the first outer support portion 811 of the first rotating member 81 in the radial direction R to the first axial side L1. In this example, the first shaft member 10 is formed integrally with the first rotating member 81. In this embodiment, the first shaft member 10 is arranged to penetrate the first side wall portion 92 of the case 9 in the axial direction L. The first shaft member 10 is supported rotatably relative to the first side wall portion 92 via the second bearing B2. In this example, the second bearing B2 is a radial bearing arranged between the first shaft member 10 and the first side wall portion 92 in the radial direction R.

[0055] In this embodiment, the second rotating member 82 is connected to the second shaft member 20 so as to rotate integrally with it. The second shaft member 20 is disposed so as to extend from the second rotating member 82 to the first axial side L1. In this embodiment, the second shaft member 20 is formed so as to extend from the first inner support portion 821 of the second rotating member 82 to the first axial side L1. The second shaft member 20 is disposed on the first axis X1. In this example, the second shaft member 20 is formed integrally with the second rotating member 82. In this embodiment, the second shaft member 20 is disposed so as to pass through the inside of the first shaft member 10 in the radial direction R. The second shaft member 20 is supported rotatably relative to the first shaft member 10 via the third bearing B3. In this example, the third bearing B3 is a radial bearing disposed between the first shaft member 10 and the second shaft member 20 in the radial direction R.

[0056] The engagement device 100 is provided, for example, in a vehicle drive device that transmits driving force from a driving force source such as an internal combustion engine to wheels. In this case, one of the first shaft member 10 and the second shaft member 20 is drivingly connected to the driving force source such as an internal combustion engine. The other of the first shaft member 10 and the second shaft member 20 is drivingly connected to the wheels.

[0057] In this manner, in this embodiment, the driving source 4 for rotating the screw shaft 331 and the transmission mechanism 5 for transmitting power between the driving source 4 and the screw shaft 331 are further provided. The drive source 4 is disposed on a different axis from the screw shaft. an arrangement area of ​​the driving source 4 in the axial direction L overlaps with an arrangement area of ​​the first rotating member 81 in the axial direction L; The transmission mechanism 5 is disposed on the second axial side L2 with respect to the linear motion mechanism 33. A first shaft member 10 is disposed so as to extend from the first rotating member 81 toward the first axial side L1, and is connected to the first rotating member 81 so as to rotate integrally with the first rotating member 81. The second shaft member 20 is disposed so as to extend from the second rotating member 82 to the first axial side L1, and is connected to the second rotating member 82 so as to rotate integrally therewith.

[0058] According to this configuration, the dimension of the engagement device 100 in the axial direction L can be kept small, compared to a configuration in which the drive source 4 is disposed coaxially with the first rotating member 81 but shifted in the axial direction L.

[0059] As shown in FIG. 1, in this embodiment, the transmission mechanism 5 includes a first gear 51, a second gear 52, a third gear 53, a fourth gear 54, and a connector 55.

[0060] The first gear 51 is connected to the output shaft of the driving source 4 so as to rotate integrally with the output shaft. In this embodiment, the first gear 51 is disposed on the second shaft X2. The first gear 51 is disposed on a second axial side L2 with respect to the driving source 4.

[0061] The second gear 52 meshes with the first gear 51. In this embodiment, the second gear 52 is formed to have a larger diameter than the first gear 51. The third gear 53 is connected to the second gear 52 so as to rotate integrally with the second gear 52. In this embodiment, the third gear 53 is formed to have a smaller diameter than the second gear 52. In addition, the third gear 53 is disposed on the axial first side L1 with respect to the second gear 52. In this embodiment, the second gear 52 and the third gear 53 are disposed on a third axis X3 different from the first axis X1 and the second axis X2. In this embodiment, the second gear 52 and the third gear 53 are supported by the first shaft body 56 so as to be rotatable with respect to the non-rotating member NR. The first shaft body 56 is formed to extend along the axial direction L. In this embodiment, the end of the first shaft body 56 on the axial first side L1 is supported rotatably with respect to the support wall portion 93. The end of the first shaft 56 on the second axial side L2 is supported by the cover portion 94 so as to be rotatable relative to the cover portion 94.

[0062] The fourth gear 54 meshes with the third gear 53. In this embodiment, the fourth gear 54 is formed to have a larger diameter than the third gear 53. In this embodiment, the fourth gear 54 is disposed on the first axis X1. In this embodiment, the fourth gear 54 is supported rotatably with respect to the non-rotating member NR by the second shaft body 57. The second shaft body 57 is formed to extend along the axial direction L. In this embodiment, an end of the second shaft body 57 on the axial second side L2 is supported rotatably with respect to the cover portion 94. On the other hand, an end of the second shaft body 57 on the axial first side L1 is connected to the connecting body 55 so as to rotate integrally therewith.

[0063] In this embodiment, the number of teeth of the second gear 52 is greater than the number of teeth of the first gear 51. The number of teeth of the fourth gear 54 is greater than the number of teeth of the third gear 53 that rotates integrally with the second gear 52. Therefore, in this embodiment, the rotation transmitted from the driving source 4 to the first gear 51 is decelerated between the first gear 51 and the second gear 52, and then transmitted to the third gear 53. The rotation of the third gear 53 is decelerated between the third gear 53 and the fourth gear 54, and then transmitted to the connecting body 55.

[0064] The connecting body 55 connects the fourth gear 54 and the screw shaft 331 so that they rotate integrally. In this embodiment, the connecting body 55 is formed in a cylindrical shape with the axial second side L2 open. The connecting body 55 and the second shaft body 57 are connected to rotate integrally in a state where the second shaft body 57 is arranged inside the connecting body 55 in the radial direction R. In this embodiment, the connecting body 55 and the screw shaft 331 are connected to rotate integrally in a state where the screw shaft 331 is arranged to extend from the connecting body 55 to the axial first side L1. In this embodiment, the connecting body 55, the second shaft body 57, and the screw shaft 331 are arranged to penetrate the support wall portion 93 in the axial direction L.

[0065] As shown in FIG. 2, in this embodiment, the connecting body 55 is disposed on the inside in the radial direction R with respect to the second inner support portion 931 of the support wall portion 93, which is formed in a cylindrical shape. In this embodiment, the connecting body 55 is provided with a supported portion 551 formed to protrude outward in the radial direction R from the connecting body 55. The second inner support portion 931 is provided with a bearing support portion 932 formed to protrude inward in the radial direction R from the second inner support portion 931 and to face the supported portion 551 from the axial first side L1. The supported portion 551 is rotatably supported by the bearing support portion 932 via the fifth bearing B5. As a result, the connecting body 55 is rotatably supported by the non-rotating member NR in a state in which the connecting body 55 is restricted from moving relative to the non-rotating member NR on the axial first side L1. In this example, the fifth bearing B5 is a thrust bearing disposed between the supported portion 551 and the bearing support portion 932 in the axial direction L.

[0066] In this embodiment, the annular lid portion 933 is fixed to the support wall portion 93 so as to face the supported portion 551 from the second axial side L2. The supported portion 551 is rotatably supported by the lid portion 933 via the sixth bearing B6. As a result, the connecting body 55 is rotatably supported by the non-rotating member NR in a state in which the connecting body 55 is restricted from moving relative to the non-rotating member NR toward the second axial side L2. In this example, the sixth bearing B6 is a thrust bearing disposed between the supported portion 551 and the lid portion 933 in the axial direction L.

[0067] In this embodiment, a pressure sensor (not shown) is provided to detect the pressing force of the pressing portion 31 against the first frictional engagement element 11 and the second frictional engagement element 12 and the pressing force of the pressing portion 31 against the third frictional engagement element 21 and the fourth frictional engagement element 22. For example, the pressure sensor is disposed between the supported portion 551 and the bearing support portion 932 in the axial direction L, or between the supported portion 551 and the lid portion 933 in the axial direction L. This allows the pressure sensor to measure the force that the pressing portion 31 receives from the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22, which is transmitted to the connecting body 55 via the driven portion 32, the nut member 332, and the screw shaft 331. Then, based on the measured force, the pressing force of the pressing portion 31 against the first frictional engagement element 11 and the second frictional engagement element 12 and the pressing force of the pressing portion 31 against the third frictional engagement element 21 and the fourth frictional engagement element 22 can be calculated.

[0068] 2. Engagement device according to the second embodiment An engagement device 100 according to a second embodiment will be described below with reference to Figs. 3 and 4. This embodiment differs from the first embodiment in that the second rotating member 82 is a target rotating member 8T. The following description will focus on the differences from the first embodiment. Note that points that are not specifically described are the same as those in the first embodiment.

[0069] 3 and 4, in this embodiment, the second rotating member 82 is the target rotating member 8T. Therefore, in this embodiment, the second rotating member 82 has a third connecting portion 8c to which the third friction engagement element 21 is connected.

[0070] As shown in FIG. 4, in this embodiment, the second rotating member 82 further includes, in addition to the first inner support portion 821, a second outer support portion 822 and a second radially extending portion 823.

[0071] The second outer support part 822 is formed in a cylindrical shape with the first axis X1 as its axis. In this embodiment, the third connecting part 8c is arranged in the second outer support part 822. On the other hand, in this embodiment, the third connecting part 8c is not arranged in the first outer support part 811 of the first rotating member 81, but the first connecting part 8a is arranged therein. The dimension of the axial direction L of the first outer support part 811 in this embodiment is smaller than the dimension of the axial direction L of the first outer support part 811 in the first embodiment. The first outer support part 811 is arranged on the first axial side L1 with respect to the second outer support part 822.

[0072] The second radial extension portion 823 is formed so as to extend along a radial direction R based on the first axis X1. In this embodiment, the second radial extension portion 823 is formed so as to extend inward in the radial direction R from an end portion of the second outer support portion 822 on the first axial side L1. The second radial extension portion 823 is supported in a state in which it is relatively movable in the axial direction L and rotates integrally with the first inner support portion 821. In this example, an inner end portion in the radial direction R of the second radial extension portion 823 is connected to the second connecting portion 8b. In this embodiment, the second radial extension portion 823 is connected to the first pressing portion 311 so as to rotate integrally with the first pressing portion 311. In this example, the second radial extension portion 823 is formed integrally with the first pressing portion 311.

[0073] 3. Vehicle drive device according to the first embodiment A vehicle drive device 1000 according to the first embodiment, which includes the engagement device 100 according to the first embodiment, will be described below with reference to Fig. 5 to Fig. 9. As shown in Fig. 5 and Fig. 6, the vehicle drive device 1000 includes a rotating electric machine MG including a stator ST and a rotor RT, an input shaft IS rotating integrally with the rotor RT, an output gear OG drivingly connected to a wheel W (see Fig. 6), a drive gear DG connected to rotate in conjunction with the output gear OG, and a transmission TM including a planetary gear mechanism PL and the engagement device 100. In this embodiment, the vehicle drive device 1000 further includes a pair of output members OM each rotating integrally with a different wheel W, and a differential gear mechanism DF that distributes the rotation of the output gear OG to the pair of output members OM.

[0074] The drive gear DG, the planetary gear mechanism PL, and the engagement device 100 are arranged on a first axis X1, which is the rotation axis of the rotor RT. In other words, the rotor RT, the planetary gear mechanism PL, the engagement device 100, and the drive gear DG are arranged coaxially. In this embodiment, the output gear OG, the pair of output members OM, and the differential gear mechanism DF are arranged on a fourth axis X4 different from the first axis X1. In this example, the first axis X1 and the fourth axis X4 are arranged parallel to each other.

[0075] In this embodiment, in the axial direction L, the side on which the rotary electric machine MG is arranged with respect to the input shaft IS is defined as a first axial side L1, and the opposite side is defined as a second axial side L2.

[0076] The rotating electric machine MG functions as a driving force source for the wheels W (see FIG. 6). The rotating electric machine MG has a function as a motor (electric motor) that receives a supply of electric power to generate power, and a function as a generator (electric power generator) that receives a supply of power to generate electric power. Specifically, the rotating electric machine MG is electrically connected to an electric storage device (not shown) such as a battery or a capacitor. The rotating electric machine MG generates driving force by running using the electric power stored in the electric storage device. The rotating electric machine MG also generates power using the driving force transmitted from the wheels W to charge the electric storage device.

[0077] A stator ST of the rotating electric machine MG is fixed to a non-rotating member NR. A rotor RT of the rotating electric machine MG is supported rotatably relative to the stator ST.

[0078] 5, in this embodiment, the non-rotating member NR is a case 9. The case 9 houses the rotating electric machine MG, the input shaft IS, the output gear OG, the drive gear DG, the transmission TM, the output member OM, and the differential gear mechanism DF. In this embodiment, in addition to the first peripheral wall portion 91, the first side wall portion 92, the support wall portion 93, and the cover portion 94, the case 9 further includes a second peripheral wall portion 91a, a third peripheral wall portion 91b, a fourth peripheral wall portion 91c, a second side wall portion 92a, a third side wall portion 92b, and a fourth side wall portion 92d.

[0079] The second peripheral wall portion 91a is formed so as to cover the outer side of the rotating electric machine MG in the radial direction R. The third peripheral wall portion 91b is formed so as to cover the outer side of the drive gear DG and the planetary gear mechanism PL in the radial direction R. The fourth peripheral wall portion 91c is formed so as to cover the outer side of the pair of output members OM and the differential gear mechanism DF in the radial direction R. In this embodiment, the first peripheral wall portion 91 is formed so as to cover the outer side of the engagement device 100 in the radial direction R.

[0080] The second side wall portion 92a is formed so as to cover the first axial side L1 of the rotating electric machine MG. The third side wall portion 92b is formed so as to separate the rotating electric machine MG from the output gear OG, the drive gear DG, and the differential gear mechanism DF in the axial direction L. The fourth side wall portion 92d is formed so as to cover the second axial side L2 of the differential gear mechanism DF. In this embodiment, the support wall portion 93 is formed so as to cover the second axial side L2 of the engagement device 100. And the cover portion 94 is formed so as to cover the second axial side L2 of the support wall portion 93. Also, the first side wall portion 92 is formed so as to separate the planetary gear mechanism PL and the engagement device 100 in the axial direction L.

[0081] In this embodiment, the second peripheral wall portion 91a is formed in a cylindrical shape having an axis along the axial direction L. An opening on the first axial side L1 of the second peripheral wall portion 91a is blocked by the second side wall portion 92a. An opening on the second axial side L2 of the second peripheral wall portion 91a is blocked by the third side wall portion 92b. In this example, the second peripheral wall portion 91a and the second side wall portion 92a are integrally formed. The third side wall portion 92b is fitted into the opening on the first axial side L1 of the second peripheral wall portion 91a from the second axial side L2.

[0082] In this embodiment, the third peripheral wall portion 91b is formed in a cylindrical shape having an axis along the axial direction L. An opening on the second axial side L2 of the third peripheral wall portion 91b is blocked by the first side wall portion 92. In this embodiment, the fourth peripheral wall portion 91c is formed in a cylindrical shape having an axis along the axial direction L. An opening on the second axial side L2 of the fourth peripheral wall portion 91c is blocked by the fourth side wall portion 92d. In this example, the third peripheral wall portion 91b, the fourth peripheral wall portion 91c, the first side wall portion 92, and the fourth side wall portion 92d are integrally formed. The ends of the third peripheral wall portion 91b and the fourth peripheral wall portion 91c on the first axial side L1 and the end of the second axial side L2 of the second peripheral wall portion 91a are joined to each other so that the openings of the third peripheral wall portion 91b and the fourth peripheral wall portion 91c on the first axial side L1 are blocked by the third side wall portion 92b.

[0083] In this embodiment, the first peripheral wall portion 91 is formed in a cylindrical shape having an axis along the axial direction L. An opening on the second axial side L2 of the first peripheral wall portion 91 is blocked by the support wall portion 93. In this example, the first peripheral wall portion 91 is formed integrally with the first side wall portion 92 so that the opening on the first axial side L1 of the first peripheral wall portion 91 is blocked by the first side wall portion 92. The support wall portion 93 is fitted into the opening on the second axial side L2 of the first peripheral wall portion 91 from the second axial side L2. Furthermore, a cover portion 94 is joined to the support wall portion 93 from the second axial side L2.

[0084] The planetary gear mechanism PL includes a first rotating element E1, a second rotating element E2, and a third rotating element E3. The planetary gear mechanism PL is configured so that the rotational speeds of the first rotating element E1, the second rotating element E2, and the third rotating element E3 are in the order described above. Here, the "order of rotational speeds" refers to the order of rotational speeds in the rotational state of each rotating element. The rotational speeds of each rotating element change depending on the rotational state of the planetary gear mechanism, but the order of high and low rotational speeds of each rotating element is fixed because it is determined by the structure of the planetary gear mechanism. The order of rotational speeds of each rotating element is equal to the arrangement order of each rotating element in the speed diagram (see FIG. 7, etc.). Here, the "arrangement order of each rotating element in the speed diagram" refers to the order in which the axes corresponding to each rotating element in the speed diagram are arranged along a direction perpendicular to the axis. The arrangement direction of the shafts corresponding to each rotating element in the velocity diagram varies depending on how the velocity diagram is drawn, but the arrangement order is fixed since it is determined by the structure of the planetary gear mechanism.

[0085] In this embodiment, the planetary gear mechanism PL is a single-pinion type planetary gear mechanism including a first sun gear S1, a first carrier C1, and a first ring gear R1.

[0086] The first rotating element E1 is connected to the input shaft IS so as to rotate integrally with the input shaft IS. In this embodiment, the first rotating element E1 is a first sun gear S1.

[0087] The second rotating element E2 is connected to the drive gear DG so as to rotate integrally with it. In this embodiment, the second rotating element E2 is the first carrier C1. The first carrier C1 rotatably supports a first pinion gear P1 that meshes with the first sun gear S1 and the first ring gear R1. The first pinion gear P1 rotates (spins) around its axis and also rotates (revolves) around the first sun gear S1 together with the first carrier C1. A plurality of first pinion gears P1 are provided at intervals from each other along the revolution trajectory.

[0088] The third rotating element E3 is switched between a first state in which it is connected to the non-rotating member NR and a second state in which it is connected to the first rotating element E1 or the second rotating element E2 so as to rotate integrally with them, depending on the engagement state of the engagement device 100. In this embodiment, the third rotating element E3 is a first ring gear R1. The first ring gear R1 is an internally toothed gear disposed on the outer side in the radial direction R with respect to the first sun gear S1 and the first carrier C1.

[0089] In this embodiment, the engagement device 100 includes a clutch mechanism 1, a brake mechanism 2, and a pressing mechanism 3.

[0090] The clutch mechanism 1 is configured to selectively engage a first rotating member 81 and a second rotating member 82 that are supported so as to be rotatable relative to each other. The clutch mechanism 1 includes a first frictional engagement element 11 connected to the first rotating member 81 so as to rotate integrally therewith, and a second frictional engagement element 12 connected to the second rotating member 82 so as to rotate integrally therewith.

[0091] The first friction engagement element 11 and the second friction engagement element 12 are disposed so as to face each other in the axial direction L. The first friction engagement element 11 and the second friction engagement element 12 are frictionally engaged with each other by being pressed in the axial direction L. In this embodiment, the first friction engagement element 11 and the second friction engagement element 12 are provided in multiple pieces and are disposed alternately along the axial direction L. Either the first friction engagement element 11 or the second friction engagement element 12 can be a friction plate, and the other can be a separate plate.

[0092] The brake mechanism 2 is configured to selectively engage a first rotating member 81 and a non-rotating member NR. The brake mechanism 2 includes a third friction engagement element 21 connected to the first rotating member 81 so as to rotate integrally with the first rotating member 81, and a fourth friction engagement element 22 fixed to the non-rotating member NR.

[0093] The third friction engagement element 21 and the fourth friction engagement element 22 are disposed so as to face each other in the axial direction L. The third friction engagement element 21 and the fourth friction engagement element 22 are frictionally engaged with each other by being pressed in the axial direction L. The third friction engagement element 21 and the fourth friction engagement element 22 are disposed so as to be spaced apart from each other on the second axial side L2 with respect to the first friction engagement element 11 and the second friction engagement element 12. In this embodiment, the third friction engagement element 21 and the fourth friction engagement element 22 are provided in multiple pieces, and are disposed alternately along the axial direction L. One of the third friction engagement element 21 and the fourth friction engagement element 22 may be a friction plate, and the other may be a separate plate.

[0094] In this embodiment, the first rotating member 81 includes a first outer support portion 811. The first outer support portion 811 is formed in a cylindrical shape with the first axis X1 as its axis. The first outer support portion 811 supports the first friction engagement element 11 and the third friction engagement element 21 from the outside in the radial direction R. In this example, a plurality of spline grooves extending in the axial direction L are formed in the outer periphery of the first friction engagement element 11 and the third friction engagement element 21 in a circumferentially distributed manner. On the other hand, similar spline grooves are also formed in the inner periphery of the first outer support portion 811 in a circumferentially distributed manner. These spline grooves are engaged with each other.

[0095] In this embodiment, the second rotating member 82 includes a first inner support portion 821. The first inner support portion 821 is disposed on the inside in the radial direction R with respect to the first outer support portion 811. The first inner support portion 821 supports the second friction engagement element 12 from the inside in the radial direction R. In this example, a plurality of spline grooves extending in the axial direction L are formed in an inner peripheral portion of the second friction engagement element 12 so as to be distributed in the circumferential direction. Meanwhile, similar spline grooves are also formed in an outer peripheral portion of the first inner support portion 821 so as to be distributed in the circumferential direction. These spline grooves are engaged with each other.

[0096] In this embodiment, the support wall 93 of the case 9 includes a second inner support portion 931. The second inner support portion 931 is disposed on the inside in the radial direction R relative to the first outer support portion 811 and on the second axial side L2 relative to the first inner support portion 821. The second inner support portion 931 supports the fourth friction engagement element 22 from the inside in the radial direction R. In this example, a plurality of spline grooves extending in the axial direction L are formed in the inner peripheral portion of the fourth friction engagement element 22 in a circumferentially distributed manner. Meanwhile, similar spline grooves are also formed in the outer peripheral portion of the second inner support portion 931 in a circumferentially distributed manner. These spline grooves are engaged with each other.

[0097] In this embodiment, the first rotating member 81 is connected to the first shaft member 10 so as to rotate integrally with the first rotating member 81. The first shaft member 10 is disposed so as to extend from the first rotating member 81 to the first axial side L1. The first shaft member 10 is disposed so as to penetrate the first side wall portion 92 of the case 9 in the axial direction L. The first shaft member 10 is connected to the first ring gear R1 of the planetary gear mechanism PL on the first axial side L1 of the first side wall portion 92 so as to rotate integrally with the first ring gear R1. The first shaft member 10 is rotatably supported by the first side wall portion 92 via the second bearing B2.

[0098] In this embodiment, the second rotating member 82 is disposed on the inside in the radial direction R with respect to the first rotating member 81. The second rotating member 82 is connected to the second shaft member 20 so as to rotate integrally with the second rotating member 82. The second shaft member 20 is disposed so as to extend from the second rotating member 82 to the first axial side L1. The second shaft member 20 is disposed on the inside in the radial direction R with respect to the first shaft member 10. The second shaft member 20 is supported via the third bearing B3 so as to be rotatable relative to the first shaft member 10. In this embodiment, the input shaft IS corresponds to the second shaft member 20.

[0099] The pressing mechanism 3 is configured to change the engagement state of the clutch mechanism 1 and the brake mechanism 2. In this embodiment, the pressing mechanism 3 includes a first pressing portion 311 that presses the first frictional engagement element 11 and the second frictional engagement element 12, a second pressing portion 312 that presses the third frictional engagement element 21 and the fourth frictional engagement element 22, a linear motion mechanism 33 that moves the first pressing portion 311 and the second pressing portion 312 in the axial direction L, and a transmission mechanism 5 that transmits the power of the drive source 4 to the linear motion mechanism 33.

[0100] In this embodiment, the first pressing portion 311 and the second pressing portion 312 are configured as separate members arranged to face each other in the axial direction L. The first pressing portion 311 and the second pressing portion 312 are supported via the fourth bearing B4 so as to be relatively rotatable with respect to each other. Therefore, in this embodiment, the first pressing portion 311 and the second pressing portion 312 are configured to move in conjunction with each other in the axial direction L while being relatively rotatable. In this example, the fourth bearing B4 is a thrust bearing arranged between the first pressing portion 311 and the second pressing portion 312 in the axial direction L.

[0101] In this embodiment, the linear motion mechanism 33 is configured by a ball screw. In this example, a nut member 332 screwed onto a screw shaft 331 of the linear motion mechanism 33 is connected to the second pressing portion 312 so as to move integrally with the second pressing portion 312 in the axial direction L.

[0102] In this embodiment, the transmission mechanism 5 is composed of a plurality of gears. In this example, the rotation from the driving source 4 is reduced in speed between the gears that mesh with each other, and is then transmitted to the linear motion mechanism 33.

[0103] When the first pressing portion 311 and the second pressing portion 312 are moved to the first axial side L1 by the linear motion mechanism 33, the first frictional engagement element 11 and the second frictional engagement element 12 are pressed by the first pressing portion 311, and the clutch mechanism 1 is in an engaged state, and the pressure of the third frictional engagement element 21 and the fourth frictional engagement element 22 by the second pressing portion 312 is released, and the brake mechanism 2 is in a released state. In this state, the first rotating member 81 rotates relative to the non-rotating member NR, and the first rotating member 81 and the second rotating member 82 rotate integrally. Therefore, the first ring gear R1 connected to the first rotating member 81, the first carrier C1 connected to the drive gear DG, and the first sun gear S1 connected to the input shaft IS and the second rotating member 82 rotate integrally. As a result, the rotation of the rotor RT is transmitted as it is to the drive gear DG (see reference symbol G2 in FIG. 7).

[0104] On the other hand, the first pressing portion 311 and the second pressing portion 312 are moved to the second axial side L2 by the linear motion mechanism 33, so that the third frictional engagement element 21 and the fourth frictional engagement element 22 are pressed by the second pressing portion 312, and the brake mechanism 2 is brought into an engaged state, and the first pressing portion 311 releases the pressure on the first frictional engagement element 11 and the second frictional engagement element 12, and the clutch mechanism 1 is brought into a released state. In this state, the relative rotation of the first rotating member 81 with respect to the non-rotating member NR is restricted, and the second rotating member 82 rotates relative to the first rotating member 81. Therefore, the first ring gear R1 connected to the first rotating member 81, the first carrier C1 connected to the drive gear DG, and the first sun gear S1 connected to the input shaft IS and the second rotating member 82 rotate relative to each other. As a result, the rotation of the rotor RT is reduced in the planetary gear mechanism PL and transmitted to the drive gear DG (see reference symbol G1 in FIG. 7).

[0105] The drive gear DG is disposed between the rotor RT and the transmission TM in the axial direction L. In this embodiment, the rotor RT, the drive gear DG, the planetary gear mechanism PL, and the engagement device 100 are disposed on the first shaft X1 in the order described from the first axial side L1 to the second axial side L2.

[0106] The input shaft IS is formed to extend in the axial direction L. The input shaft IS is disposed to penetrate the drive gear DG in the axial direction L. The input shaft IS connects the rotor RT and the first rotating element E1 (here, the first sun gear S1) so as to rotate integrally with each other. In this embodiment, the input shaft IS is supported via the fifth bearing B5 so as to be rotatable relative to the drive gear DG. In this embodiment, the input shaft IS penetrates the third side wall portion 92b of the case 9 in the axial direction L. The input shaft IS is supported via the sixth bearing B6 so as to be rotatable relative to the third side wall portion 92b. In this embodiment, the input shaft IS penetrates the planetary gear mechanism PL in the axial direction L and is connected to the second rotating member 82 so as to rotate integrally with the second rotating member 82. The input shaft IS is supported via the seventh bearing B7 so as to be rotatable relative to the first carrier C1 of the planetary gear mechanism PL.

[0107] The output gear OG has a larger diameter than the drive gear DG. Therefore, the rotation of the drive gear DG is reduced between the drive gear DG and the output gear OG. In this embodiment, the output gear OG is directly meshed with the drive gear DG.

[0108] In this embodiment, the output gear OG is disposed so as to overlap both the rotating electric machine MG and the planetary gear mechanism PL when viewed in the axial direction along the axial direction L. In the example shown in Fig. 5, the output gear OG is disposed so as to overlap the stator ST and rotor RT of the rotating electric machine MG and the first sun gear S1, the first carrier C1, and the first ring gear R1 of the planetary gear mechanism PL when viewed in the axial direction along the axial direction L. Here, with regard to the arrangement of two elements, "overlapping when viewed in a specific direction" refers to the existence of at least a part of an area where a virtual line parallel to the line of sight intersects with both of the two elements when the virtual line is moved in each direction perpendicular to the virtual line.

[0109] According to this configuration, the diameter of the output gear OG can be increased, and a large reduction ratio between the drive gear DG and the output gear OG can be easily ensured, which makes it easier to reduce the size of the rotating electric machine MG. Furthermore, with this configuration, it is easy to keep the inter-axis distance between the drive gear DG and the output gear OG (the distance in the radial direction R between the first shaft X1 and the fourth shaft X4) small. Therefore, it is easy to keep the dimension of the vehicle drive device 1000 in the radial direction R small.

[0110] In this embodiment, the driving gear DG has a smaller diameter than the first sun gear S1 of the planetary gear mechanism PL. According to this configuration, the difference in size between the driving gear DG and the output gear OG in the radial direction R is increased, and it is easy to ensure a large reduction ratio between the driving gear DG and the output gear OG. As a result, it is easy to reduce the size of the rotating electric machine MG. In this embodiment, the driving gear DG has a smaller diameter than the first carrier C1 of the planetary gear mechanism PL. In this example, the driving gear DG has a smaller diameter than the revolution path of the first pinion gear P1 supported by the first carrier C1. According to this configuration, when the first pinion gear P1 is assembled to the planetary gear mechanism PL from the side of the driving gear DG in the axial direction L (here, the first axial side L1), the first pinion gear P1 can be easily assembled while avoiding interference with the driving gear DG.

[0111] A pair of output members OM are arranged side by side in the axial direction L. The output member OM on the first axial side L1 is connected to a wheel W on the first axial side L1 via a first drive shaft DS1 (see FIG. 6) extending in the axial direction L so as to rotate integrally with the wheel W on the first axial side L1. The output member OM on the second axial side L2 is connected to a wheel W on the second axial side L2 via a second drive shaft DS2 (see FIG. 6) extending in the axial direction L so as to rotate integrally with the wheel W on the second axial side L2. In the following description, the output member OM on the first axial side L1 is referred to as the "first output member OM1," and the output member OM on the second axial side L2 is referred to as the "second output member OM2."

[0112] The differential gear mechanism DF is a planetary gear type differential gear mechanism including a second sun gear S2, a second carrier C2, and a second ring gear R2. In this embodiment, the differential gear mechanism DF is a double-pinion type planetary gear mechanism. Therefore, in this embodiment, the second carrier C2 rotatably supports an inner pinion gear P21 meshed with the second sun gear S2 and an outer pinion gear P22 meshed with the second ring gear R2.

[0113] The second sun gear S2 is connected to the first output member OM1 so as to rotate integrally with it. In this embodiment, the first output member OM1 is disposed so as to extend from the second sun gear S2 to the first axial side L1. The first output member OM1 is supported via an eighth bearing B8 so as to be relatively rotatable with respect to the second carrier C2. In this embodiment, the first output member OM1 is disposed so as to penetrate the third side wall portion 92b and the second side wall portion 92a of the case 9 in the axial direction L. The first output member OM1 is supported rotatably with respect to the third side wall portion 92b via a ninth bearing B9, and is supported rotatably with respect to the second side wall portion 92a via a tenth bearing B10.

[0114] The second carrier C2 is connected to the second output member OM2 so as to rotate integrally with it. In this embodiment, the second output member OM2 is disposed so as to extend from the second carrier C2 to the second axial side L2. The second output member OM2 is supported via an eleventh bearing B11 so as to be rotatable relative to the second ring gear R2. In this embodiment, the second output member OM2 is disposed so as to penetrate the fourth side wall portion 92d of the case 9 in the axial direction L. The second output member OM2 is supported via a twelfth bearing B12 so as to be rotatable relative to the fourth side wall portion 92d so as to be rotatable relative to the fourth side wall portion 92d.

[0115] The second ring gear R2 is connected to the output gear OG so as to rotate integrally with the output gear OG. In this embodiment, the second ring gear R2 is disposed on the inner side of the output gear OG in the radial direction R. Furthermore, the second ring gear R2 is disposed so as to overlap with the output gear OG when viewed in the radial direction R.

[0116] FIG. 7 shows a speed diagram of the planetary gear mechanism PL according to this embodiment. In the speed diagram of FIG. 7, the vertical lines correspond to the rotational speeds of the respective rotating elements of the planetary gear mechanism PL. Each of the multiple vertical lines arranged in parallel corresponds to each rotating element of the planetary gear mechanism PL. In addition, in the speed diagram of FIG. 7, the symbols shown above the multiple vertical lines are the symbols of the corresponding rotating elements of the planetary gear mechanism PL. And the symbols shown below the multiple vertical lines are the symbols of the elements that rotate integrally with the rotating elements corresponding to the symbols shown above. In addition, in the speed diagram of FIG. 7, the black circle on the vertical line corresponding to the third rotating element E3 indicates that the brake mechanism 2 is in a direct engagement state. Note that the "direct engagement state" is an engagement state in which there is no rotational speed difference between the input element and the output element of the friction engagement device.

[0117] When the brake mechanism 2 is in an engaged state and the clutch mechanism 1 is in a released state, the transmission TM is in a first gear position G1. In this state, as shown in Fig. 7, the first ring gear R1 connected to the first rotating member 81, the first carrier C1 connected to the drive gear DG, and the first sun gear S1 connected to the input shaft IS and the second rotating member 82 rotate relative to one another. As a result, the rotation of the rotor RT is reduced in the planetary gear mechanism PL at a gear ratio according to the first gear position G1 and transmitted to the drive gear DG.

[0118] On the other hand, when the clutch mechanism 1 is in an engaged state and the brake mechanism 2 is in a released state, the second gear G2 is established in the transmission TM. In this state, the first ring gear R1 connected to the first rotating member 81, the first carrier C1 connected to the drive gear DG, and the first sun gear S1 connected to the input shaft IS and the second rotating member 82 rotate integrally. As a result, the gear ratio according to the second gear G2 becomes 1, and the rotation of the rotor RT is transmitted as is to the drive gear DG.

[0119] 4. Vehicle drive device according to the second embodiment The vehicle drive device 1000 according to the second embodiment will be described below with reference to Figs. 8 and 9. The vehicle drive device 1000 according to this embodiment differs from the vehicle drive device 1000 according to the first embodiment in that the output gear OG does not directly mesh with the drive gear DG, but meshes with an idler gear IG that meshes with the drive gear DG. The following mainly describes the differences from the vehicle drive device 1000 according to the first embodiment. Note that points that are not particularly described are the same as those of the vehicle drive device 1000 according to the first embodiment.

[0120] 8 and 9, in this embodiment, as described above, the output gear OG meshes with the idler gear IG which meshes with the drive gear DG. That is, the output gear OG and the drive gear DG mesh with the idler gear IG at different positions in the circumferential direction of the idler gear IG.

[0121] In this embodiment, the output gear OG overlaps with the rotating electric machine MG when viewed in the axial direction L, but does not overlap with the planetary gear mechanism PL.

[0122] In this embodiment, the case 9 does not include the second circumferential wall portion 91a and the second side wall portion 92a. Accordingly, in this embodiment, the tenth bearing B10 that rotatably supports the first output member OM1 with respect to the second side wall portion 92a is not provided. Furthermore, the dimension of the first output member OM1 in the axial direction L is shorter than that of the first embodiment.

[0123] In this embodiment, the third side wall portion 92b is integrally formed with the third peripheral wall portion 91b and the fourth peripheral wall portion 91c. The first side wall portion 92 is formed of a separate member from the third peripheral wall portion 91b.

[0124] As described above, the vehicle drive device 1000 has the following features: a rotating electric machine MG having a rotor RT; An input shaft IS that rotates integrally with the rotor RT; An output gear OG drivingly connected to the wheels W; A vehicle drive device 1000 including a transmission TM including a planetary gear mechanism PL and an engagement device 100, The planetary gear mechanism PL includes a first rotating element E1, a second rotating element E2, and a third rotating element E3, and is configured such that the order of rotation speeds of the first rotating element E1, the second rotating element E2, and the third rotating element E3 is as described above. The first rotating element E1 is connected to the input shaft IS so as to rotate integrally with the input shaft IS, The second rotating element E2 is connected to the drive gear DG so as to rotate integrally with the drive gear DG. The third rotating element E3 is switched between a first state in which it is coupled to the non-rotating member NR and a second state in which it is coupled to the first rotating element E1 or the second rotating element E2 so as to rotate integrally with the first rotating element E1 or the second rotating element E2, depending on the engagement state of the engagement device 100. The rotor RT, the planetary gear mechanism PL, the engagement device 100, and the drive gear DG are arranged coaxially. The drive gear DG is disposed between the rotor RT and the transmission TM in the axial direction L, The input shaft IS passes through the drive gear DG in the axial direction L and connects the rotor RT and the first rotating element E1 so as to rotate integrally with each other. The output gear OG has a larger diameter than the drive gear DG. A drive gear DG and an output gear OG mesh with each other, or an idler gear IG, which meshes with the drive gear DG, and the output gear OG mesh with each other.

[0125] According to this configuration, the drive gear DG, which is connected to rotate integrally with the second rotating element E2 of the planetary gear mechanism PL, meshes directly or via an idler gear IG with the output gear OG, which is formed to have a larger diameter than the drive gear DG. This allows the rotation of the second rotating element E2 transmitted to the drive gear DG to be decelerated between the drive gear DG and the output gear OG. Therefore, the configuration of the vehicle drive device 1000 can be simplified compared to a configuration including a planetary gear mechanism PL that decelerates the rotation of the second rotating element E2. To explain further, in a configuration without an idler gear IG, when the third rotating element E3 is in the second state, there is only one mesh of gears in the power transmission path from the rotating electric machine MG to the output gear OG, that is, the mesh between the drive gear DG and the output gear OG. On the other hand, when the third rotating element E3 is in the first state, only the meshing inside the planetary gear mechanism PL is increased. In this way, it is easy to improve the transmission efficiency of the power transmission path from the rotating electric machine MG to the output gear OG because the overall number of gear meshes of the vehicle drive device 1000 is small. Also, even if the configuration includes the idler gear IG, the number of gear meshes is increased by only one compared to a configuration not including the idler gear IG, and similarly, it is easy to improve the transmission efficiency of the power transmission path from the rotating electric machine MG to the output gear OG. Also, according to this configuration, the rotor RT, the transmission TM, and the drive gear DG are arranged coaxially, and the drive gear DG is arranged between the rotor RT and the transmission TM in the axial direction L. This makes it possible to reduce the radial dimension R of the vehicle drive device 1000 compared to a configuration in which the drive gear DG is arranged to overlap at least one of the rotor RT and the transmission TM when viewed in the radial direction R. Furthermore, by increasing the difference in the radial dimension R between the drive gear DG and the output gear OG, it is easy to ensure a large reduction ratio between the drive gear DG and the output gear OG. As a result, it is easy to reduce the size of the rotating electric machine MG. As described above, according to this configuration, in a configuration including the transmission TM having the planetary gear mechanism PL and the engagement device 100, a vehicle drive device 1000 that is small in size and has a simple configuration can be realized.

[0126] In the first and second embodiments, the vehicle drive device 1000 is Further, an output member OM that rotates integrally with the wheel W is provided, The output gear OG is disposed coaxially with the output member OM.

[0127] According to this configuration, the output gear OG, which meshes directly or via an idler gear IG with the drive gear DG, which is arranged coaxially with the rotor RT and the transmission TM, is arranged coaxially with the output member OM, which rotates integrally with the wheel W. This makes it easy to keep the number of shafts small as a whole in the vehicle drive device 1000. Therefore, the dimension of the vehicle drive device 1000 in the radial direction R can be kept small.

[0128] In the first and second embodiments, the vehicle drive device 1000 is A pair of output members OM each rotating integrally with a different wheel W; a planetary gear type differential gear mechanism DF including a second sun gear S2, a second carrier C2, and a second ring gear R2, and distributing rotation of the output gear OG to a pair of output members OM; The output gear OG is disposed outside the ring gear in the radial direction R and at a position overlapping with the ring gear as viewed in the radial direction R.

[0129] According to this configuration, since the differential gear mechanism DF is of the planetary gear type, it is easier to keep the dimension of the vehicle drive device 1000 in the axial direction L small, compared to a configuration in which the differential gear mechanism DF is of the bevel gear type. Furthermore, according to this configuration, the output gear OG is disposed radially outward of the second ring gear R2. This allows the output gear OG to have a large diameter, making it easier to ensure a large reduction ratio between the drive gear DG and the output gear OG, and thus makes it easier to reduce the size of the rotating electric machine MG. Furthermore, according to this configuration, the output gear OG is disposed so as to overlap with the second ring gear R2 as viewed in the radial direction R. This makes it possible to reduce the dimension of the vehicle driving device 1000 in the axial direction L compared to a configuration in which the output gear OG is disposed offset in the axial direction L with respect to the second ring gear R2.

[0130] In the first and second embodiments described above, the planetary gear mechanism PL is disposed on the rotor RT side with respect to the engagement device 100 in the axial direction L.

[0131] This configuration makes it easy to simplify the connection structure between the first rotating element E1 of the planetary gear mechanism PL and the rotor RT, and the connection structure between the second rotating element E2 of the planetary gear mechanism PL and the drive gear DG, thereby making it easy to reduce the size of the vehicle drive device 1000.

[0132] 5. Vehicle drive device according to the third embodiment Hereinafter, a vehicle drive device 1000 according to a third embodiment, which includes the engagement device 100 according to the second embodiment, will be described with reference to Figs. 10 to 12. As shown in Figs. 10 and 11, the vehicle drive device 1000 includes a rotating electric machine MG including a stator ST and a rotor RT, an input member IM to which the rotation of the rotor RT is transmitted, an output member OM which rotates integrally with a wheel W (see Fig. 11), a speed reducer RD which reduces the rotation of the input member IM and transmits it to the output member OM, and a brake mechanism 2 which selectively engages the input member IM with a non-rotating member NR. In this embodiment, the vehicle drive device 1000 further includes a clutch mechanism 1 which selectively engages the rotor RT with the input member IM, a drive mechanism 7 which changes the engagement state of both the brake mechanism 2 and the clutch mechanism 1, and a case 9 as a non-rotating member NR. In this embodiment, the vehicle drive device 1000 is configured as a drive device for the wheel W, which is called an in-wheel motor.

[0133] The rotor RT, the input member IM, the output member OM, and the brake mechanism 2 are arranged coaxially. In other words, the rotor RT, the input member IM, and the brake mechanism 2 are arranged coaxially with the output member OM that rotates integrally with the wheel W, that is, coaxially with the rotation axis of the wheel W. In this embodiment, the reducer RD and the clutch mechanism 1 are also arranged coaxially therewith.

[0134] 10 , the case 9 houses the rotating electric machine MG, the input member IM, the output member OM, the reducer RD, the brake mechanism 2, the clutch mechanism 1, and the drive mechanism 7. In this embodiment, the case 9 houses the output member OM and the drive mechanism 7 with parts of them exposed to the outside. In this embodiment, the case 9 further includes a fifth side wall portion 95 and a sixth side wall portion 96 in addition to the first circumferential wall portion 91, the first side wall portion 92, the support wall portion 93, and the cover portion 94.

[0135] The first peripheral wall portion 91 is formed in a cylindrical shape with openings on a first axial side L1 and a second axial side L2. The fifth side wall portion 95 and the sixth side wall portion 96 are formed to extend along the radial direction R. The fifth side wall portion 95 is disposed so as to close the opening on the first axial side L1 of the first peripheral wall portion 91. The sixth side wall portion 96 is disposed so as to close the opening on the second axial side L2 of the first peripheral wall portion 91.

[0136] The first side wall portion 92 is formed to extend inward in the radial direction R from the first circumferential wall portion 91. The first side wall portion 92 is disposed between the fifth side wall portion 95 and the sixth side wall portion 96 in the axial direction L. In this embodiment, the reducer RD is disposed between the first side wall portion 92 and the fifth side wall portion 95 in the axial direction L. In addition, the rotating electric machine MG, the brake mechanism 2, and the clutch mechanism 1 are disposed between the first side wall portion 92 and the sixth side wall portion 96 in the axial direction L.

[0137] The cover portion 94 is formed so as to cover the second axial side L2 of the sixth side wall portion 96. In this embodiment, a plurality of vehicle body connecting members C1 for connecting the vehicle drive device 1000 to a vehicle body are distributed and arranged in a circumferential direction about the rotation axis of the rotor RT so as to protrude from the sixth side wall portion 96 to the second axial side L2. The cover portion 94 is arranged on the inside in the radial direction R of the plurality of vehicle body connecting members C1.

[0138] The rotating electric machine MG functions as a driving force source for the wheels W (see FIG. 11). The rotating electric machine MG has a function as a motor (electric motor) that receives a supply of electric power to generate power, and a function as a generator (electric power generator) that receives a supply of power to generate electric power. Specifically, the rotating electric machine MG is electrically connected to an electric storage device (not shown) such as a battery or a capacitor. The rotating electric machine MG generates driving force by running using the electric power stored in the electric storage device. The rotating electric machine MG also generates power using the driving force transmitted from the wheels W to charge the electric storage device.

[0139] A stator ST of the rotating electric machine MG is fixed to a non-rotating member NR. In this embodiment, the stator ST is fixed to a first circumferential wall portion 91 of the case 9. A rotor RT of the rotating electric machine MG is supported rotatably relative to the stator ST. In this embodiment, the rotor RT is disposed on the inside in the radial direction R relative to the stator ST.

[0140] 12, in this embodiment, the rotating electric machine MG further includes a rotor support member 13. The rotor support member 13 is a member that supports the rotor RT rotatably relative to the case 9. In this embodiment, the rotor support member 13 includes an outer cylindrical portion 131, an inner cylindrical portion 132, and a connection portion 133.

[0141] The outer cylindrical portion 131 is formed in a cylindrical shape coaxial with the rotor RT. The outer cylindrical portion 131 is disposed so as to support the rotor RT from the inside in the radial direction R. In this embodiment, the outer cylindrical portion 131 corresponds to the first rotating member 81.

[0142] The inner cylindrical portion 132 is formed in a cylindrical shape coaxial with the outer cylindrical portion 131. The inner cylindrical portion 132 is formed to have a smaller diameter than the outer cylindrical portion 131. In this embodiment, the inner cylindrical portion 132 is rotatably supported with respect to the first side wall portion 92 of the case 9 via a second bearing B2. The second bearing B2 is a radial bearing arranged between the inner cylindrical portion 132 and the first side wall portion 92 in the radial direction R. In the illustrated example, the second bearing B2 is a ball bearing arranged to support the inner cylindrical portion 132 from the outside in the radial direction R. In this embodiment, the inner cylindrical portion 132 corresponds to the first shaft member 10.

[0143] The connecting portion 133 extends along the radial direction R so as to connect the outer cylindrical portion 131 and the inner cylindrical portion 132. In this embodiment, an outer end of the connecting portion 133 in the radial direction R is connected to an end of the outer cylindrical portion 131 on a first axial side L1. Also, an inner end of the connecting portion 133 in the radial direction R is connected to an end of the inner cylindrical portion 132 on a second axial side L2. In the illustrated example, the outer cylindrical portion 131, the inner cylindrical portion 132, and the connecting portion 133 are integrally formed.

[0144] In this embodiment, the connection portion 133 is rotatably supported with respect to the first side wall portion 92 of the case 9 via a first bearing B1. The first bearing B1 is a thrust bearing arranged between the connection portion 133 and the first side wall portion 92 in the axial direction L. In the illustrated example, the first bearing B1 is a ball bearing arranged to support the connection portion 133 from the first axial side L1.

[0145] In this embodiment, the input member IM includes a second rotating member 82 and a second shaft member 20. The second shaft member 20 is disposed so as to penetrate the first side wall portion 92 of the case 9 in the axial direction L. In this embodiment, the second shaft member 20 is disposed on the inside in the radial direction R with respect to the inner cylindrical portion 132 of the rotor support member 13. The second shaft member 20 is supported via a third bearing B3 so as to be rotatable relative to the inner cylindrical portion 132. The third bearing B3 is a radial bearing disposed between the second shaft member 20 and the inner cylindrical portion 132 in the radial direction R.

[0146] In this embodiment, the brake mechanism 2 and the clutch mechanism 1 are arranged side by side in the axial direction L. In the illustrated example, the clutch mechanism 1 is arranged on a first axial side L1 relative to the brake mechanism 2.

[0147] As shown in FIG. 12, in this embodiment, the brake mechanism 2 includes a third friction engagement element 21, a fourth friction engagement element 22, a second outer support portion 822, a second inner support portion 931, and a second pressing portion 312.

[0148] The third friction engagement element 21 and the fourth friction engagement element 22 are disposed to face each other in the axial direction L. The third friction engagement element 21 and the fourth friction engagement element 22 are frictionally engaged with each other by being pressed in the axial direction L. In this embodiment, each of the third friction engagement element 21 and the fourth friction engagement element 22 is formed in a disk shape coaxial with the rotor RT. A plurality of each of the third friction engagement element 21 and the fourth friction engagement element 22 are provided, and these are alternately disposed along the axial direction L. One of the third friction engagement element 21 and the fourth friction engagement element 22 can be a friction plate, and the other can be a separate plate.

[0149] The second outer support portion 822 supports the third friction engagement element 21 slidably in the axial direction L so as to rotate integrally with the third friction engagement element 21. In this embodiment, the second outer support portion 822 is formed in a cylindrical shape coaxial with the rotor RT. The second outer support portion 822 supports the third friction engagement element 21 from the outside in the radial direction R. In this example, a plurality of spline teeth extending in the axial direction L are formed in a circumferentially distributed manner on the inner peripheral portion of the second outer support portion 822. On the other hand, similar spline teeth are also formed in a circumferentially distributed manner on the outer peripheral portion of the third friction engagement element 21. These spline teeth are engaged with each other.

[0150] The second inner support portion 931 supports the fourth friction engagement element 22 slidably in the axial direction L so as to rotate integrally with the fourth friction engagement element 22. In this embodiment, the second inner support portion 931 is coaxial with the second outer support portion 822 and is formed in a cylindrical shape having a smaller diameter than the second outer support portion 822. The second inner support portion 931 supports the fourth friction engagement element 22 from the inside in the radial direction R. In this example, a plurality of spline teeth extending in the axial direction L are formed on the outer periphery of the second inner support portion 931 in a circumferentially distributed manner. On the other hand, similar spline teeth are also formed on the inner periphery of the fourth friction engagement element 22 in a circumferentially distributed manner. These spline teeth are engaged with each other.

[0151] The second outer support portion 822 is connected to the input member IM so as to rotate integrally therewith. The second inner support portion 931 is fixed to the non-rotating member NR. In this embodiment, the second inner support portion 931 is fixed to a support wall portion 93 included in the case 9 as the non-rotating member NR. The support wall portion 93 is formed so as to extend along the radial direction R. In this embodiment, the support wall portion 93 is joined from the axial first side L1 to a portion of the sixth side wall portion 96 covered by the cover portion 94. In the illustrated example, the second inner support portion 931 is formed integrally with the support wall portion 93 so as to protrude from the support wall portion 93 to the axial first side L1.

[0152] The second pressing portion 312 is configured to press the third frictional engagement element 21 and the fourth frictional engagement element 22. In this embodiment, the second pressing portion 312 is formed to extend along the radial direction R. The second pressing portion 312 is disposed to press the third frictional engagement element 21 and the fourth frictional engagement element 22 from the first axial side L1.

[0153] In this embodiment, the clutch mechanism 1 includes a first frictional engagement element 11, a second frictional engagement element 12, a first outer support portion 811, a first inner support portion 821, and a first pressing portion 311.

[0154] The first friction engagement element 11 and the second friction engagement element 12 are disposed so as to face each other in the axial direction L. The first friction engagement element 11 and the second friction engagement element 12 are frictionally engaged with each other by being pressed in the axial direction L. In this embodiment, each of the first friction engagement element 11 and the second friction engagement element 12 is formed in a disk shape coaxial with the rotor RT. A plurality of each of the first friction engagement elements 11 and the second friction engagement elements 12 are provided, and these are alternately disposed along the axial direction L. One of the first friction engagement element 11 and the second friction engagement element 12 can be a friction plate, and the other can be a separate plate.

[0155] The first outer support portion 811 supports the first friction engagement element 11 slidably in the axial direction L so as to rotate integrally with the first friction engagement element 11. In this embodiment, the first outer support portion 811 is formed in a cylindrical shape coaxial with the rotor RT. The first outer support portion 811 supports the first friction engagement element 11 from the outside in the radial direction R. In this example, a plurality of spline teeth extending in the axial direction L are formed in a circumferentially distributed manner on the inner peripheral portion of the first outer support portion 811. On the other hand, similar spline teeth are also formed in a circumferentially distributed manner on the outer peripheral portion of the first friction engagement element 11. These spline teeth are engaged with each other.

[0156] The first inner support portion 821 supports the second friction engagement element 12 slidably in the axial direction L so as to rotate integrally with the second friction engagement element 12. In this embodiment, the first inner support portion 821 is coaxial with the first outer support portion 811 and is formed in a cylindrical shape having a smaller diameter than the first outer support portion 811. The first inner support portion 821 supports the second friction engagement element 12 from the inside in the radial direction R. In this example, a plurality of spline teeth extending in the axial direction L are formed on the outer periphery of the first inner support portion 821 in a circumferentially distributed manner. On the other hand, similar spline teeth are also formed on the inner periphery of the second friction engagement element 12 in a circumferentially distributed manner. These spline teeth are engaged with each other.

[0157] The first pressing portion 311 is configured to press the first frictional engagement element 11 and the second frictional engagement element 12. In this embodiment, the first pressing portion 311 is formed to extend along the radial direction R. The first pressing portion 311 is disposed to press the first frictional engagement element 11 and the second frictional engagement element 12 from the axial second side L2. In this embodiment, the first pressing portion 311 is connected to the second outer support portion 822 of the brake mechanism 2 so as to rotate integrally with the second outer support portion 822. In the illustrated example, the first pressing portion 311 and the second outer support portion 822 are formed integrally such that the outer end of the first pressing portion 311 in the radial direction R and the end of the second outer support portion 822 on the axial first side L1 are connected to each other.

[0158] In this embodiment, the first pressing portion 311 is supported via a fourth bearing B4 so as to be rotatable relative to the second pressing portion 312. The fourth bearing B4 is a thrust bearing disposed between the first pressing portion 311 and the second pressing portion 312 in the axial direction L. In the illustrated example, the fourth bearing B4 is a ball bearing disposed so as to support the first pressing portion 311 from the second axial side L2 and to support the second pressing portion 312 from the first axial side L1.

[0159] The first outer support part 811 is connected to the rotor RT so as to rotate integrally with the rotor RT. In this embodiment, the first outer support part 811 is connected to the outer cylindrical part 131 of the rotor support member 13 from the inside in the radial direction R. In the illustrated example, the first outer support part 811 is formed integrally with the outer cylindrical part 131.

[0160] The first inner support portion 821 is connected to the input member IM so as to rotate integrally with the input member IM. In this embodiment, the first inner support portion 821 is connected from the outside in the radial direction R to a portion of the input member IM that is located on the second axial side L2 relative to the connection portion 133 of the rotor support member 13 (here, the second rotating member 82). In the illustrated example, the first inner support portion 821 is formed integrally with the input member IM.

[0161] The first inner support portion 821 is connected to the second outer support portion 822 of the brake mechanism 2 so as to rotate integrally therewith. In this embodiment, the first inner support portion 821 supports the first pressing portion 311 slidably in the axial direction L so as to rotate integrally with the first pressing portion 311 connected to the second outer support portion 822. In this example, spline teeth that engage with spline teeth formed on the outer periphery of the first inner support portion 821 are formed on the inner periphery of the first pressing portion 311 in a circumferentially dispersed manner. These spline teeth are engaged with each other. In this way, the third friction engagement element 21 of the brake mechanism 2 and the second friction engagement element 12 of the clutch mechanism 1 rotate integrally.

[0162] The brake mechanism 2 is disposed on the inside in the radial direction R of the rotor RT of the rotating electric machine MG, at a position overlapping with the rotor RT as viewed in the radial direction R. Here, with regard to the arrangement of two elements, "overlapping as viewed in a specific direction" means that when a virtual line parallel to the line of sight is moved in each direction perpendicular to the virtual line, there exists at least a part of an area where the virtual line intersects both of the two elements.

[0163] In this embodiment, the clutch mechanism 1 is also disposed on the inside in the radial direction R with respect to the rotor RT, at a position overlapping with the rotor RT as viewed in the radial direction R.

[0164] As described above, since the reducer RD is provided to reduce the rotation of the input member IM and transmit it to the output member OM, the moment of inertia of the rotor RT acts on the output member OM after being amplified according to the reduction ratio of the reducer RD. As a result, when a large torque fluctuation is transmitted from the wheel W to the output member OM due to, for example, the wheel W climbing over a step or traveling on a wavy road, the torque acting on the transmission path of the driving force is likely to become excessive. In response to this, if the strength of the members arranged on the transmission path of the driving force is increased, the members will end up becoming larger. According to this configuration, a clutch mechanism 1 is provided that selectively engages the rotor RT and the input member IM. As a result, when excessive torque acts on the path of transmission of the driving force, the clutch mechanism 1 slips, and it is possible to prevent the driving force transmitted between the rotor RT and the input member IM from becoming excessive. Therefore, it is possible to reduce the size of the members disposed on the path of transmission of the driving force. Furthermore, according to this configuration, by putting the clutch mechanism 1 into a released state, the rotor RT can be separated from the input member IM (and thus the wheels W). This makes it possible to stop the rotating electric machine MG while the vehicle is running by inertia or while the vehicle is running by the driving force of another driving source. Therefore, the energy efficiency of the vehicle driving device 1000 can be improved.

[0165] The drive mechanism 7 is configured to change between a first state in which the brake mechanism 2 is in an engaged state and the clutch mechanism 1 is in a released state, and a second state in which the brake mechanism 2 is in a released state and the clutch mechanism 1 is in an engaged state. In this embodiment, the drive mechanism 7 is also configured to change to a third state in which the brake mechanism 2 is in a released state and the clutch mechanism 1 is in a released state. In the third state, as described above, the rotating electric machine MG can be stopped while the vehicle is running by inertia or while the vehicle is running by the driving force of another driving source. As shown in FIG. 10, in this embodiment, the drive mechanism 7 includes a linear motion mechanism 33, a transmission mechanism 5, and a driving source 4.

[0166] The linear motion mechanism 33 is configured to move the second pressing portion 312 of the brake mechanism 2 and the first pressing portion 311 of the clutch mechanism 1 in the axial direction L. In this embodiment, the second pressing portion 312 and the first pressing portion 311 are disposed between the third friction engagement element 21 and the fourth friction engagement element 22 and the first friction engagement element 11 and the second friction engagement element 12 in the axial direction L. Therefore, the linear motion mechanism 33 is configured to easily move both the second pressing portion 312 and the first pressing portion 311.

[0167] As shown in FIG. 12, in this embodiment, the linear motion mechanism 33 includes a threaded shaft 331 rotatably supported by a non-rotating member NR, and a nut member 332 that screws onto the threaded shaft 331.

[0168] A screw thread is formed on the outer periphery of the screw shaft 331. The screw shaft 331 is formed to extend along the axial direction L. In this embodiment, the screw shaft 331 is arranged coaxially with the brake mechanism 2 and the clutch mechanism 1. In this embodiment, the screw shaft 331 is arranged inside the second inner support portion 931 of the brake mechanism 2 in the radial direction R and at a position overlapping with the second inner support portion 931 as viewed in the radial direction along the radial direction R.

[0169] A groove that engages with the thread of the screw shaft 331 is formed on the inner periphery of the nut member 332. When the screw shaft 331 rotates, the nut member 332 performs linear motion along the axial direction L according to the direction of rotation of the screw shaft 331 and the orientation of the thread of the screw shaft 331.

[0170] In this embodiment, the nut member 332 is connected to the second pressing portion 312 of the brake mechanism 2 so as to move in the axial direction L together with the second pressing portion 312. As described above, in this embodiment, the fourth bearing B4 is disposed between the second pressing portion 312 and the first pressing portion 311 in the axial direction L. Therefore, in this embodiment, when the screw shaft 331 rotates so that the nut member 332 moves to the first axial side L1, the second pressing portion 312 moves to the first axial side L1 via the nut member 332, and the first pressing portion 311 also moves to the first axial side L1 via the fourth bearing B4. As a result, the first frictional engagement element 11 and the second frictional engagement element 12 are pressed by the first pressing portion 311, the clutch mechanism 1 is in an engaged state, and the pressing of the third frictional engagement element 21 and the fourth frictional engagement element 22 by the second pressing portion 312 is released, and the brake mechanism 2 is in a released state. In this state, power is transmitted between the rotor RT and the input member IM.

[0171] On the other hand, in this embodiment, when the screw shaft 331 rotates so that the nut member 332 moves to the second axial side L2, the second pressing portion 312 moves to the second axial side L2 via the nut member 332. As a result, the third frictional engagement element 21 and the fourth frictional engagement element 22 are pressed by the second pressing portion 312, the brake mechanism 2 is brought into an engaged state, and the pressing of the first frictional engagement element 11 and the second frictional engagement element 12 by the first pressing portion 311 is released, and the clutch mechanism 1 is brought into a released state. In this state, power transmission between the rotor RT and the input member IM is interrupted.

[0172] The transmission mechanism 5 is configured to transmit the power of the drive source 4 to the linear motion mechanism 33. As shown in Fig. 10, in this embodiment, the transmission mechanism 5 includes a first gear 51, a second gear 52, a third gear 53, a fourth gear 54, and a connecting body 55.

[0173] The first gear 51 is connected to the output shaft of the driving source 4 so as to rotate integrally with the output shaft. In this embodiment, the first gear 51 is arranged coaxially with the screw shaft 331 of the linear motion mechanism 33. The first gear 51 is arranged on a first axial side L1 with respect to the driving source 4.

[0174] The second gear 52 meshes with the first gear 51. In this embodiment, the second gear 52 is formed to have a larger diameter than the first gear 51. The third gear 53 is connected to the second gear 52 so as to rotate integrally with the second gear 52. In this embodiment, the third gear 53 is formed to have a smaller diameter than the second gear 52. The third gear 53 is disposed on the first axial side L1 with respect to the second gear 52. In this embodiment, the second gear 52 and the third gear 53 are supported rotatably with respect to the case 9 by the first shaft body 56. The first shaft body 56 is formed to extend along the axial direction L. In this embodiment, the first shaft body 56 is disposed to penetrate the sixth side wall portion 96 in the axial direction L. The end of the first shaft body 56 on the first axial side L1 is supported rotatably with respect to the support wall portion 93. Further, an end portion of the first shaft body 56 on the second axial side L2 is supported by the cover portion 94 so as to be rotatable relative to the cover portion 94.

[0175] The fourth gear 54 meshes with the third gear 53. In this embodiment, the fourth gear 54 is formed to have a larger diameter than the third gear 53. In this embodiment, the fourth gear 54 is arranged coaxially with the screw shaft 331 of the linear motion mechanism 33. In this embodiment, the fourth gear 54 is connected to the connecting body 55 via the second shaft body 57 so as to rotate integrally with the connecting body 55. The second shaft body 57 is formed to extend along the axial direction L. In this embodiment, the second shaft body 57 is arranged to penetrate the sixth side wall portion 96 and the support wall portion 93 in the axial direction L.

[0176] In this embodiment, the number of teeth of the second gear 52 is greater than the number of teeth of the first gear 51. The number of teeth of the fourth gear 54 is greater than the number of teeth of the third gear 53 that rotates integrally with the second gear 52. Therefore, in this embodiment, the rotation transmitted from the driving source 4 to the first gear 51 is decelerated between the first gear 51 and the second gear 52, and then transmitted to the third gear 53. The rotation of the third gear 53 is decelerated between the third gear 53 and the fourth gear 54, and then transmitted to the connecting body 55.

[0177] As shown in FIG. 12, the connecting body 55 connects the fourth gear 54 and the screw shaft 331 so that they rotate integrally. In this embodiment, the connecting body 55 is formed in a cylindrical shape with the axial second side L2 open. Then, in a state where the second shaft body 57 is arranged inside the connecting body 55 in the radial direction R, the connecting body 55 and the second shaft body 57 are connected to rotate integrally. In this embodiment, in a state where the screw shaft 331 is arranged to protrude from the connecting body 55 to the axial first side L1, the connecting body 55 and the screw shaft 331 are connected to rotate integrally. In this embodiment, the connecting body 55 is arranged inside the radial direction R with respect to the second inner support part 931 of the brake mechanism 2, and is arranged at a position overlapping with the second inner support part 931 as viewed in the radial direction along the radial direction R.

[0178] The driving source 4 is a device that generates power for driving the linear motion mechanism 33. In this embodiment, the driving source 4 is supported by the cover portion 94. In the illustrated example, the driving source 4 is connected to the cover portion 94 from the second axial side L2. In this example, the driving source 4 is an electric motor.

[0179] As described above, in this embodiment, the vehicle drive device 1000 further includes the drive mechanism 7 that changes the engagement states of both the brake mechanism 2 and the clutch mechanism 1. The brake mechanism 2 and the clutch mechanism 1 are arranged side by side in the axial direction L, The drive mechanism 7 is configured to change between a first state in which the brake mechanism 2 is engaged and the clutch mechanism 1 is released, and a second state in which the brake mechanism 2 is released and the clutch mechanism 1 is engaged.

[0180] According to this configuration, the engagement states of both the brake mechanism 2 and the clutch mechanism 1 can be changed by the common drive mechanism 7. Therefore, it is easier to reduce the size of the vehicle drive device 1000 compared to a configuration in which the brake mechanism 2 and the clutch mechanism 1 are each driven by a separate drive mechanism.

[0181] In this embodiment, the reducer RD is a planetary gear mechanism including a sun gear SG, a carrier CR, and a ring gear RG. Here, the reducer RD is a single-pinion type planetary gear mechanism. In this embodiment, the reducer RD is disposed at a position that does not overlap with the rotating electric machine MG when viewed in the radial direction R. In the illustrated example, the reducer RD is disposed on a first axial side L1 of the rotating electric machine MG.

[0182] As shown in FIG. 10, in this embodiment, the sun gear SG is connected to the input member IM so as to rotate integrally with it. That is, in this embodiment, the sun gear SG is an input element of the speed reducer RD. In the illustrated example, the sun gear SG is formed in a portion of the input member IM that is located on the first axial side L1 from the first side wall portion 92 of the case 9. Also, in this embodiment, the sun gear SG is disposed on the inner side in the radial direction R from the rotor RT. In the illustrated example, the sun gear SG is disposed on the inner side in the radial direction R from the third friction engagement element 21 and the fourth friction engagement element 22 of the brake mechanism 2 and the first friction engagement element 11 and the second friction engagement element 12 of the clutch mechanism 1.

[0183] The carrier CR rotatably supports the pinion gear PG. The pinion gear PG meshes with the sun gear SG and the ring gear RG. The pinion gear PG rotates (spins) around its axis and also rotates (revolves) around the sun gear SG together with the carrier CR. A plurality of pinion gears PG are provided at intervals from each other along the orbital path.

[0184] In this embodiment, the carrier CR is connected to the output member OM so as to rotate integrally with the output member OM. That is, in this embodiment, the carrier CR is an output element of the speed reducer RD. In addition, in this embodiment, the carrier CR includes a first supported part CRa rotatably supported with respect to the case 9 via a thirteenth bearing B13, and a second supported part CRb rotatably supported with respect to the case 9 via a fourteenth bearing B14.

[0185] In this embodiment, the first supported part CRa is formed in a cylindrical shape coaxial with the sun gear SG. The first supported part CRa is disposed on the first axial side L1 with respect to the pinion gear PG so as to penetrate the fifth side wall part 95 of the case 9 in the axial direction L. The thirteenth bearing B13 is a radial bearing disposed between the first supported part CRa and the fifth side wall part 95 in the radial direction R. In the illustrated example, the thirteenth bearing B13 is disposed so as to support the first supported part CRa from the outside in the radial direction R. The thirteenth bearing B13 is an angular ball bearing in which a virtual line (line of action) passing through a contact point between the rolling element of the thirteenth bearing B13 and a raceway ring is inclined with respect to the axial direction L.

[0186] In this embodiment, the second supported part CRb is formed in a cylindrical shape coaxial with the first supported part CRa. The second supported part CRb is disposed on the second axial side L2 with respect to the pinion gear PG. The fourteenth bearing B14 is a radial bearing disposed between the second supported part CRb and the first side wall part 92 of the case 9 in the radial direction R. In the illustrated example, the fourteenth bearing B14 is disposed so as to support the second supported part CRb from the inside in the radial direction R. The fourteenth bearing B14 is an angular ball bearing in which a virtual line (line of action) passing through a contact point between the rolling element of the fourteenth bearing B14 and the raceway ring is inclined with respect to the axial direction L. Here, the thirteenth bearing B13 and the fourteenth bearing B14 are disposed so that the directions in which their lines of action are inclined with respect to the axial direction L are opposite to each other.

[0187] In this embodiment, the ring gear RG is fixed to the case 9. In the illustrated example, the ring gear RG is integrally formed with a first side wall portion 92 of the case 9. Also, in this embodiment, the ring gear RG is disposed so as to overlap with the stator ST when viewed in the axial direction L.

[0188] As described above, in this embodiment, the reducer RD is a planetary gear mechanism including the sun gear SG, the carrier CR, and the ring gear RG, and is disposed in a position that does not overlap with the rotating electric machine MG as viewed in the radial direction R. The rotor RT is disposed on the inside in the radial direction R with respect to the stator ST of the rotating electric machine MG. The ring gear RG is arranged so as to overlap with the stator ST when viewed in the axial direction along the axial direction L, The sun gear SG is disposed radially inward of the rotor RT.

[0189] This configuration makes it possible to ensure a large dimensional difference between the ring gear RG and the sun gear SG in the radial direction R. This makes it easy to ensure a large reduction ratio of the reducer RD.

[0190] In the present embodiment, the reducer RD is configured with one planetary gear mechanism. With this configuration, the size of the reducer RD in the axial direction L can be kept small, compared to a configuration in which, for example, a parallel shaft gear mechanism and a planetary gear mechanism are arranged in the axial direction L.

[0191] In this embodiment, the output member OM is a wheel hub. In this embodiment, the output member OM includes a coupling portion OMa and a joint portion OMb.

[0192] The connecting part OMa is connected to the output element of the reducer RD so as to rotate integrally with the output element. In this embodiment, the connecting part OMa is formed to extend along the axial direction L. The connecting part OMa is connected to the first supported part CRa of the carrier CR so as to rotate integrally with the first supported part CRa in a state in which the connecting part OMa is disposed on the inside in the radial direction R with respect to the first supported part CRa of the carrier CR.

[0193] The joint portion OMb is configured to be joined to the wheel W. In this embodiment, the joint portion OMb is formed so as to protrude outward in the radial direction R from a portion of the coupling portion OMa that is on the first axial side L1 beyond the first supported portion CRa of the carrier CR. The joint portion OMb is coupled to the wheel W in a state where it is disposed on the second axial side L2 with respect to the wheel W by a plurality of wheel coupling members C2 that are distributed in the circumferential direction about the axis of the joint portion OMb.

[0194] In this manner, in this embodiment, the output member OM is a wheel hub having a joint portion OMb that is joined to the wheel W, The reducer RD is disposed between the joint OMb and the rotating electric machine MG in the axial direction L.

[0195] With this configuration, compared to a configuration in which the reducer RD is arranged so as to overlap with the rotating electric machine MG when viewed radially along the radial direction R, it is easier to keep the radial direction R dimension of the vehicle driving device 1000 small while ensuring a large radial direction R dimension of the rotating electric machine MG.

[0196] As described above, the vehicle drive device 1000 has the following features: a rotating electric machine MG having a rotor RT; an input member IM to which the rotation of the rotor RT is transmitted; An output member OM that rotates integrally with the wheel W; A reducer RD that reduces the rotation speed of the input member IM and transmits the rotation speed to the output member OM; A vehicle drive device 1000 including a brake mechanism 2 that selectively engages an input member IM and a non-rotating member NR, The brake mechanism 2 is disposed on the radially inner side of the rotor RT in the radial direction R and at a position overlapping with the rotor RT as viewed in the radial direction along the radial direction R, The rotor RT, the input member IM, and the brake mechanism 2 are arranged coaxially with the output member OM.

[0197] According to this configuration, the rotor RT is disposed outside the brake mechanism 2 in the radial direction R. As a result, the rotating electric machine MG is larger in the radial direction R than the brake mechanism 2, and it is easy to increase the output torque by increasing the diameter of the rotating electric machine MG. Also, according to this configuration, the brake mechanism 2 is disposed at a position overlapping with the rotor RT as viewed in the radial direction along the radial direction R. As a result, the dimension in the axial direction L of the vehicle drive device 1000 can be kept small compared to a configuration in which the brake mechanism 2 is disposed on one side of the rotor RT in the axial direction L. Therefore, according to this configuration, it is possible to keep the dimension in the axial direction L small while ensuring a large output torque of the rotating electric machine MG. Moreover, according to this configuration, the rotor RT, the input member IM, and the brake mechanism 2 are arranged coaxially with the output member OM that rotates integrally with the wheel W. This makes it possible to realize a configuration suitable for a drive device for the wheel W, such as an in-wheel motor.

[0198] 6. Other embodiments (1) In the engagement device 100 according to the above embodiment, a configuration in which the linear motion mechanism 33 is disposed on the second axial side L2 with respect to the second connecting portion 8b has been described as an example. However, the present invention is not limited to such a configuration, and for example, the linear motion mechanism 33 may be disposed so as to overlap with the second connecting portion 8b when viewed in the radial direction along the radial direction R.

[0199] (2) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the linear motion mechanism 33 is disposed on the inside in the radial direction R of the fourth connecting portion 8d of the non-rotating member NR and at a position overlapping with the fourth connecting portion 8d as viewed in the radial direction along the radial direction R. However, the present invention is not limited to such a configuration, and the linear motion mechanism 33 may be disposed shifted to the first axial side L1 or the second axial side L2 with respect to the fourth connecting portion 8d.

[0200] (3) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the driven portion 32 is connected to the second pressing portion 312 supported in a state in which relative rotation with respect to the non-rotating member NR is restricted so as to move in the axial direction L integrally with the second pressing portion 312. However, the configuration is not limited to this, and the driven portion 32 may be connected to the first pressing portion 311 supported in a state in which the driven portion 32 rotates integrally with the first rotating member 81 or the second rotating member 82 so as to move in the axial direction L integrally with the first pressing portion 311.

[0201] (4) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the linear motion mechanism 33 includes the screw shaft 331 and the nut member 332. However, the linear motion mechanism 33 is not limited to such a configuration, and may include, for example, a rail and a slide member that slides along the rail.

[0202] (5) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the threaded shaft 331 is arranged coaxially with the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22 and disposed on the inside in the radial direction R. However, the present invention is not limited to such a configuration, and the threaded shaft 331 may be arranged on a different axis from the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22. Furthermore, the threaded shaft 331 may be arranged on the outside in the radial direction R with respect to the first frictional engagement element 11, the second frictional engagement element 12, the third frictional engagement element 21, and the fourth frictional engagement element 22.

[0203] (6) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the driving source 4 is disposed on a different axis from the threaded shaft 331, and the arrangement region of the driving source 4 in the axial direction L overlaps with the arrangement region of the first rotating member 81 in the axial direction L. However, the present invention is not limited to such a configuration, and the driving source 4 may be disposed coaxially with the threaded shaft 331. In addition, the driving source 4 may be disposed shifted to the first axial side L1 or the second axial side L2 with respect to the first rotating member 81.

[0204] (7) In the engagement device 100 according to the above embodiment, a configuration has been described as an example in which the transmission mechanism 5 reduces the speed of the rotation of the driving source 4 and transmits the rotation to the screw shaft 331. However, the present invention is not limited to such a configuration, and for example, the transmission mechanism 5 may transmit the rotation of the driving source 4 to the screw shaft 331 as is.

[0205] (8) In the vehicle drive device 1000 according to the first and second embodiments, the planetary gear mechanism PL is a single-pinion planetary gear mechanism. However, the invention is not limited to such a configuration, and the planetary gear mechanism PL may be a double-pinion planetary gear mechanism. In this case, for example, the first rotating element E1 may be the first sun gear S1, the second rotating element E2 may be the first ring gear R1, and the third rotating element E3 may be the first carrier C1.

[0206] (9) In the vehicle drive device 1000 according to the first and second embodiments, a configuration including a differential gear mechanism DF that distributes the rotation of the output gear OG to a pair of output members OM has been described as an example. However, the present invention is not limited to such a configuration, and a configuration that does not include the differential gear mechanism DF and transmits the rotation of the output gear OG to one output member OM may also be used.

[0207] (10) In the vehicle driving device 1000 according to the first and second embodiments, the output gear OG is disposed coaxially with the output member OM. However, the present invention is not limited to such a configuration, and the output gear OG may be disposed on a different axis from the output member OM.

[0208] (11) In the vehicle drive device 1000 according to the first and second embodiments, the differential gear mechanism DF is a planetary gear type differential gear mechanism. However, the present invention is not limited to such a configuration, and may be, for example, a bevel gear type differential gear mechanism including a pair of side gears connected to different output members OM so as to rotate integrally with each other, and a plurality of pinion gears meshing with the pair of side gears.

[0209] (12) In the vehicle drive device 1000 according to the first and second embodiments described above, the planetary gear mechanism PL is disposed on the rotor RT side (first axial side L1) in the axial direction L with respect to the engagement device 100. However, the present invention is not limited to such a configuration, and the planetary gear mechanism PL may be disposed on the opposite side to the rotor RT side (second axial side L2) in the axial direction L with respect to the engagement device 100.

[0210] (13) In the above-described vehicle driving device 1000 according to the third embodiment, the vehicle driving device 1000 is configured as an in-wheel motor, and the output member OM is provided with a joint OMb where the output member OM is joined to the wheel W. However, the present invention is not limited to such a configuration. For example, the output member OM may be a drive shaft connected to the wheel W so as to rotate integrally therewith.

[0211] (14) In the vehicle drive device 1000 according to the third embodiment, a configuration including the clutch mechanism 1 that selectively engages the rotor RT and the input member IM has been described as an example. However, the present invention is not limited to such a configuration, and the configuration may not include the clutch mechanism 1.

[0212] (15) The vehicle drive device 1000 according to the third embodiment has been described as having a configuration including the drive mechanism 7 that changes the engagement state of both the brake mechanism 2 and the clutch mechanism 1. However, the present invention is not limited to such a configuration, and for example, a configuration may be adopted in which a drive mechanism that changes the engagement state of the brake mechanism 2 and a drive mechanism that changes the engagement state of the clutch mechanism 1 are provided independently.

[0213] (16) In the vehicle driving device 1000 according to the third embodiment, a configuration has been described as an example in which the reduction gear RD is disposed at a position that does not overlap with the rotating electric machine MG when viewed in the radial direction along the radial direction R. However, the configuration is not limited to this, and the reduction gear RD may be disposed so as to overlap with the rotating electric machine MG when viewed in the radial direction along the radial direction R.

[0214] (17) In the vehicle drive device 1000 according to the third embodiment, the configuration in which the reduction gear RD is a single-pinion planetary gear mechanism has been described as an example. However, the present invention is not limited to such a configuration, and the reduction gear RD may be, for example, a double-pinion planetary gear mechanism. In this case, for example, the sun gear SG may be connected to the input member IM so as to rotate integrally therewith, the ring gear RG may be connected to the output member OM so as to rotate integrally therewith, and the carrier CR may be fixed to the non-rotating member NR.

[0215] (18) In the vehicle driving device 1000 according to the third embodiment, the reduction gear RD is configured by one planetary gear mechanism. However, the reduction gear RD is not limited to such a configuration, and may be configured by, for example, a parallel shaft gear mechanism including gears arranged on separate shafts and meshing with each other.

[0216] (19) The configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction occurs. As for other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0217] [Summary of the above embodiment] The above-described engagement device (100) will now be outlined.

[0218] The engagement device (100) is a clutch mechanism (1) that selectively engages a first rotating member (81) and a second rotating member (82); an engagement device (100) including a brake mechanism (2) that selectively engages a target rotating member (8T), which is either the first rotating member (81) or the second rotating member (82), with a non-rotating member (NR), a pressing mechanism (3) for changing the engagement state of the clutch mechanism (1) and the brake mechanism (2), A direction along the rotation axis of the first rotating member (81) is defined as an axial direction (L), one side of the axial direction (L) is defined as an axial first side (L1), and the other side of the axial direction (L) is defined as an axial second side (L2), the clutch mechanism (1) includes a first friction engagement element (11) connected to the first rotating member (81) so as to rotate integrally with the first rotating member (81), and a second friction engagement element (12) connected to the second rotating member (82) so as to rotate integrally with the second rotating member (82), the first friction engagement element (11) and the second friction engagement element (12) are disposed to face each other in the axial direction (L) and are frictionally engaged with each other by being pressed in the axial direction (L); the brake mechanism (2) includes a third friction engagement element (21) connected to the target rotating member (8T) so as to rotate integrally with the target rotating member (8T), and a fourth friction engagement element (22) fixed to the non-rotating member (NR), the third friction engagement element (21) and the fourth friction engagement element (22) are disposed to face each other in the axial direction (L) at a position spaced apart from the first friction engagement element (11) and the second friction engagement element (12) on the second axial side (L2), and are pressed in the axial direction (L) to frictionally engage with each other, the pressing mechanism (3) includes a pressing portion (31) arranged between the first friction engagement element (11), the second friction engagement element (12), and the third friction engagement element (21), and the fourth friction engagement element (22) in the axial direction (L), a driven portion (32) connected to interlock with the pressing portion (31), and a linear motion mechanism (33) that moves the driven portion (32) in the axial direction (L); the first rotating member (81), the second rotating member (82), the first friction engagement element (11), the second friction engagement element (12), the third friction engagement element (21), and the fourth friction engagement element (22) are coaxially arranged, The clutch mechanism (1) and the brake mechanism (2) are selectively engaged in response to the linear motion mechanism (33) moving the driven part (32) toward the first axial side (L1) or the second axial side (L2).

[0219] According to this configuration, the pressing portion (31), which is moved in the axial direction (L) via the driven portion (32) by the linear motion mechanism (33), is disposed between the first frictional engagement element (11) and the second frictional engagement element (12) and the third frictional engagement element (21) and the fourth frictional engagement element (22) disposed on the second axial side (L2) relative to the first frictional engagement element (11) and the second frictional engagement element (12). When the driven portion (32) is moved to the first axial side (L1) by the linear motion mechanism (33), the first frictional engagement element (11) and the second frictional engagement element (12) are pressed by the pressing portion (31), so that the clutch mechanism (1) is brought into an engaged state, and the pressing of the third frictional engagement element (21) and the fourth frictional engagement element (22) by the pressing portion (31) is released, so that the brake mechanism (2) is brought into a released state. On the other hand, when the driven part (32) is moved to the second axial side (L2) by the linear motion mechanism (33), the third friction engagement element (21) and the fourth friction engagement element (22) are pressed by the pressing part (31) to bring the brake mechanism (2) into an engaged state, and the pressing of the first friction engagement element (11) and the second friction engagement element (12) by the pressing part (31) is released to bring the clutch mechanism (1) into a released state. This allows the engagement state of the clutch mechanism (1) and the brake mechanism (2) to be changed by the common pressing mechanism (3). Therefore, in a configuration including the clutch mechanism (1) and the brake mechanism (2), the engagement device (100) can be made smaller in size.

[0220] Here, the first rotating member (81) includes a first connecting portion (8a) to which the first friction engagement element (11) is connected, the second rotating member (82) includes a second connecting portion (8b) to which the second friction engagement element (12) is connected, the target rotating member (8T) includes a third connecting portion (8c) to which the third friction engagement element (21) is connected, the non-rotating member (NR) includes a fourth connecting portion (8d) to which the fourth friction engagement element (22) is connected, the first connecting portion (8a) is disposed on the outer side of the first friction engagement element (11) in the radial direction (R) and at a position overlapping with the first friction engagement element (11) as viewed in the radial direction along the radial direction (R); the third connecting portion (8c) is disposed on the outer side of the third friction engagement element (21) in the radial direction (R) and at a position overlapping with the third friction engagement element (21) as viewed in the radial direction, the second connecting portion (8b) is disposed on the inner side of the second friction engagement element (12) in the radial direction (R) and at a position overlapping with the second friction engagement element (12) and the first connecting portion (8a) as viewed in the radial direction, the fourth connecting portion (8d) is disposed on the inner side of the fourth friction engagement element (22) in the radial direction (R) and at a position overlapping with the fourth friction engagement element (22) and the third connecting portion (8c) as viewed in the radial direction, It is preferable that the linear motion mechanism (33) is arranged on the second axial side (L2) with respect to the second connecting portion (8b), and is arranged on the inside of the fourth connecting portion (8d) in the radial direction (R) and at a position overlapping with the fourth connecting portion (8d) when viewed in the radial direction.

[0221] According to this configuration, the linear motion mechanism (33) is disposed on the second axial side (L2) with respect to the second connecting portion (8b) of the second rotating member (82). This makes it possible to reduce the radial dimension (R) of the engagement device (100) compared to a configuration in which the linear motion mechanism (33) is disposed so as to overlap with the second connecting portion (8b) as viewed in the radial direction. According to this configuration, the linear motion mechanism (33) is disposed on the radially inner side of the fourth connecting portion (8d) of the non-rotating member (NR) in the radial direction (R) and at a position overlapping with the fourth connecting portion (8d) as viewed in the radial direction (R). This makes it possible to reduce the axial (L) dimension of the engagement device (100) compared to a configuration in which the linear motion mechanism (33) is disposed offset in the axial direction (L) from the fourth connecting portion (8d). In addition, since the linear motion mechanism (33) disposed on the radially inner side of the fourth connecting portion (8d) of the non-rotating member (NR) in the radial direction (R) can be easily supported by the non-rotating member (NR), the support structure of the linear motion mechanism (33) can be easily simplified.

[0222] Moreover, the pressing portion (31) includes a first pressing portion (311) that presses the first friction engagement element (11) and the second friction engagement element (12) in the axial direction (L), and a second pressing portion (312) that presses the third friction engagement element (21) and the fourth friction engagement element (22) in the axial direction (L), the first pressing portion (311) is supported in a state in which it is movable relative to the first rotating member (81) or the second rotating member (82) in the axial direction (L) and rotates integrally with the first rotating member (81) or the second rotating member (82); the second pressing portion (312) is supported in a state in which it is movable relative to the non-rotating member (NR) in the axial direction (L) and the relative rotation is restricted, the first pressing portion (311) and the second pressing portion (312) are configured to move in conjunction with each other in the axial direction (L) while being capable of rotating relative to each other; It is preferable that the driven portion (32) is connected to the second pressing portion (312) so as to move integrally with the second pressing portion (312) in the axial direction (L).

[0223] According to this configuration, the driven part (32), which is moved in the axial direction (L) by the linear motion mechanism (33), is connected to the second pressing part (312), which is supported in a state in which its relative rotation is restricted with respect to the non-rotating member (NR), so as to move in the axial direction (L) together with the second pressing part (312). This makes it easier to simplify the pressing mechanism (3), compared to a configuration in which the driven part (32) is connected to the first pressing part (311), which is supported in a state in which it rotates integrally with the first rotating member (81) or the second rotating member (82), so as to move in the axial direction (L) together with the first pressing part (311).

[0224] The linear motion mechanism (33) further includes a threaded shaft (331) rotatably supported relative to the non-rotating member (NR), and a nut member (332) screwed onto the threaded shaft (331), the nut member (332) is connected to the driven portion (32) so as to move integrally with the driven portion (32) in the axial direction (L); It is preferable that the screw shaft (331) is arranged coaxially with and radially inwardly of the first friction engagement element (11), the second friction engagement element (12), the third friction engagement element (21), and the fourth friction engagement element (22).

[0225] According to this configuration, the threaded shaft (331) for moving the nut member (332) in the axial direction (L) is disposed on the inside in the radial direction (R) of the first frictional engagement element (11), the second frictional engagement element (12), the third frictional engagement element (21), and the fourth frictional engagement element (22). This makes it easy to transmit a driving force for rotating the threaded shaft (331) to the threaded shaft (331) from the outside in the axial direction (L) of the frictional engagement elements (11, 12, 21, 22). This makes it easy to realize a structure in which the pressing portion (31) disposed between the first frictional engagement element (11) and the second frictional engagement element (12) and the third frictional engagement element (21) and the fourth frictional engagement element (22) in the axial direction (L) can be moved in the axial direction (L) via the nut member (332) and the driven portion (32). Moreover, according to this configuration, it is easy to arrange the screw shaft (331) of the linear motion mechanism (33) so as to overlap at least a portion of the first frictional engagement element (11), the second frictional engagement element (12), the third frictional engagement element (21), and the fourth frictional engagement element (22) as viewed in the radial direction (R). This makes it possible to prevent the engagement device (100) from becoming large in the axial direction (L) due to the arrangement of the linear motion mechanism (33).

[0226] In a configuration in which the linear motion mechanism (33) includes the screw shaft (331) and the nut member (332), The engagement device (100) further includes a drive source (4) for rotationally driving the screw shaft (331), and a transmission mechanism (5) for transmitting power between the drive source (4) and the screw shaft (331), The drive source (4) is disposed on a different axis from the screw shaft (331), an arrangement area of ​​the driving source (4) in the axial direction (L) overlaps with an arrangement area of ​​the first rotating member (81) in the axial direction (L); the transmission mechanism (5) is disposed on the second axial side (L2) with respect to the linear motion mechanism (33), a first shaft member (10) disposed to extend from the first rotating member (81) toward the first axial side (L1) is connected to the first rotating member (81) so as to rotate integrally with the first rotating member (81); It is preferable that a second shaft member (20) arranged to extend from the second rotating member (82) toward the first axial side (L1) is connected to the second rotating member (82) so as to rotate integrally with the second rotating member (82).

[0227] According to this configuration, the axial (L) dimension of the engagement device (100) can be kept small compared to a configuration in which the drive source (4) is arranged coaxially with the first rotating member (81) but shifted in the axial direction (L). [Industrial Applicability]

[0228] The technology disclosed herein can be used in an engagement device that includes a clutch mechanism and a brake mechanism. [Explanation of symbols]

[0229] 100: engagement device, 1: clutch mechanism, 11: first friction engagement element, 12: second friction engagement element, 2: brake mechanism, 21: third friction engagement element, 22: fourth friction engagement element, 3: pressing mechanism, 31: pressing portion, 32: driven portion, 33: linear motion mechanism, 81: first rotating member, 82: second rotating member, 8T: target rotating member, 10: first shaft member, 20: second shaft member, NR: non-rotating member, L: axial direction, L1: first axial side, L2: second axial side

Claims

1. a clutch mechanism for selectively engaging the first rotating member and the second rotating member; a brake mechanism that selectively engages a target rotating member, which is one of the first rotating member and the second rotating member, with a non-rotating member, a pressing mechanism for changing an engagement state of the clutch mechanism and the brake mechanism, A direction along the rotation axis of the first rotating member is defined as an axial direction, one side in the axial direction is defined as an axial first side, and the other side in the axial direction is defined as an axial second side, the clutch mechanism includes a first friction engagement element connected to the first rotating member so as to rotate integrally with the first rotating member, and a second friction engagement element connected to the second rotating member so as to rotate integrally with the second rotating member, the first friction engagement element and the second friction engagement element are disposed to face each other in the axial direction and are frictionally engaged with each other by being pressed against each other in the axial direction; the brake mechanism includes a third friction engagement element connected to the target rotating member so as to rotate integrally with the target rotating member, and a fourth friction engagement element fixed to the non-rotating member, the third friction engagement element and the fourth friction engagement element are disposed to face each other in the axial direction at a position spaced apart from the first friction engagement element and the second friction engagement element on the second axial side, and are pressed against each other in the axial direction to frictionally engage with each other, the pressing mechanism includes a pressing portion disposed between the first friction engagement element and the second friction engagement element and the third friction engagement element and the fourth friction engagement element in the axial direction, a driven portion connected to be interlocked with the pressing portion, and a linear motion mechanism that moves the driven portion in the axial direction, the first rotating member, the second rotating member, the first frictional engagement element, the second frictional engagement element, the third frictional engagement element, and the fourth frictional engagement element are coaxially arranged, the clutch mechanism and the brake mechanism are selectively engaged in response to the driven part being moved toward the first axial side or the second axial side by the linear motion mechanism, the first rotating member includes a first connecting portion to which the first friction engagement element is connected, the second rotating member includes a second connecting portion to which the second friction engagement element is connected, the target rotating member includes a third connecting portion to which the third friction engagement element is connected, the non-rotating member includes a fourth connecting portion to which the fourth friction engagement element is connected, the first connecting portion is disposed radially outward of the first friction engagement element and at a position overlapping with the first friction engagement element as viewed in the radial direction, the third connecting portion is disposed on the radial outer side of the third friction engagement element and at a position overlapping with the third friction engagement element as viewed in the radial direction, the second connecting portion is disposed on the radially inner side of the second friction engagement element and at a position overlapping with the second friction engagement element and the first connecting portion as viewed in the radial direction, the fourth connecting portion is disposed on the radially inner side of the fourth friction engagement element and at a position overlapping with the fourth friction engagement element and the third connecting portion as viewed in the radial direction, An engagement device, wherein the linear motion mechanism is arranged on the second axial side relative to the second connecting portion, and is arranged radially inward relative to the fourth connecting portion at a position overlapping with the fourth connecting portion when viewed in the radial direction.

2. a clutch mechanism for selectively engaging the first rotating member and the second rotating member; a brake mechanism that selectively engages a target rotating member, which is one of the first rotating member and the second rotating member, with a non-rotating member, a pressing mechanism for changing an engagement state of the clutch mechanism and the brake mechanism, A direction along the rotation axis of the first rotating member is defined as an axial direction, one side in the axial direction is defined as an axial first side, and the other side in the axial direction is defined as an axial second side, the clutch mechanism includes a first friction engagement element connected to the first rotating member so as to rotate integrally with the first rotating member, and a second friction engagement element connected to the second rotating member so as to rotate integrally with the second rotating member, the first friction engagement element and the second friction engagement element are disposed to face each other in the axial direction and are frictionally engaged with each other by being pressed against each other in the axial direction; the brake mechanism includes a third friction engagement element connected to the target rotating member so as to rotate integrally with the target rotating member, and a fourth friction engagement element fixed to the non-rotating member, the third friction engagement element and the fourth friction engagement element are disposed to face each other in the axial direction at a position spaced apart from the first friction engagement element and the second friction engagement element on the second axial side, and are pressed against each other in the axial direction to frictionally engage with each other, the pressing mechanism includes a pressing portion disposed between the first friction engagement element and the second friction engagement element and the third friction engagement element and the fourth friction engagement element in the axial direction, a driven portion connected to be interlocked with the pressing portion, and a linear motion mechanism that moves the driven portion in the axial direction, the first rotating member, the second rotating member, the first frictional engagement element, the second frictional engagement element, the third frictional engagement element, and the fourth frictional engagement element are coaxially arranged, the clutch mechanism and the brake mechanism are selectively engaged in response to the driven part being moved toward the first axial side or the second axial side by the linear motion mechanism, the pressing portion includes a first pressing portion that presses the first friction engagement element and the second friction engagement element in the axial direction, and a second pressing portion that presses the third friction engagement element and the fourth friction engagement element in the axial direction, the first pressing portion is supported in a state in which it is movable relative to the first rotating member or the second rotating member in the axial direction and rotates integrally with the first rotating member or the second rotating member, the second pressing portion is supported in a state in which it is movable relative to the non-rotating member in the axial direction and the relative rotation is restricted with respect to the non-rotating member, The first pressing portion and the second pressing portion are configured to move in conjunction with each other in the axial direction while being capable of rotating relative to each other, An engagement device, wherein the driven portion is connected to the second pressing portion so as to move integrally with the second pressing portion in the axial direction.

3. a clutch mechanism for selectively engaging the first rotating member and the second rotating member; a brake mechanism that selectively engages a target rotating member, which is one of the first rotating member and the second rotating member, with a non-rotating member, a pressing mechanism for changing an engagement state of the clutch mechanism and the brake mechanism, A direction along the rotation axis of the first rotating member is defined as an axial direction, one side in the axial direction is defined as an axial first side, and the other side in the axial direction is defined as an axial second side, the clutch mechanism includes a first friction engagement element connected to the first rotating member so as to rotate integrally with the first rotating member, and a second friction engagement element connected to the second rotating member so as to rotate integrally with the second rotating member, the first friction engagement element and the second friction engagement element are disposed to face each other in the axial direction and are frictionally engaged with each other by being pressed against each other in the axial direction; the brake mechanism includes a third friction engagement element connected to the target rotating member so as to rotate integrally with the target rotating member, and a fourth friction engagement element fixed to the non-rotating member, the third friction engagement element and the fourth friction engagement element are disposed to face each other in the axial direction at a position spaced apart from the first friction engagement element and the second friction engagement element on the second axial side, and are pressed against each other in the axial direction to frictionally engage with each other, the pressing mechanism includes a pressing portion disposed between the first friction engagement element and the second friction engagement element and the third friction engagement element and the fourth friction engagement element in the axial direction, a driven portion connected to be interlocked with the pressing portion, and a linear motion mechanism that moves the driven portion in the axial direction, the first rotating member, the second rotating member, the first frictional engagement element, the second frictional engagement element, the third frictional engagement element, and the fourth frictional engagement element are coaxially arranged, the clutch mechanism and the brake mechanism are selectively engaged in response to the driven part being moved toward the first axial side or the second axial side by the linear motion mechanism, The linear motion mechanism includes a screw shaft rotatably supported relative to the non-rotating member, and a nut member screwed onto the screw shaft, the nut member is connected to the driven part so as to move integrally with the driven part in the axial direction, The screw shaft is arranged coaxially and radially inward with respect to the first friction engagement element, the second friction engagement element, the third friction engagement element, and the fourth friction engagement element, Further comprising a drive source for rotating the screw shaft, and a transmission mechanism for transmitting power between the drive source and the screw shaft, The drive source is disposed on a separate axis from the screw shaft, an arrangement area of ​​the driving source in the axial direction overlaps with an arrangement area of ​​the first rotating member in the axial direction, the transmission mechanism is disposed on the second axial side with respect to the linear motion mechanism, a first shaft member disposed to extend from the first rotating member to a first side in the axial direction; and the first shaft member is connected to the first rotating member so as to rotate integrally with the first rotating member; An engagement device comprising: a second shaft member arranged to extend from the second rotating member toward the first side in the axial direction; and connected to the second rotating member so as to rotate integrally with the second rotating member.

Images