unit

Abstract

[Problem] To improve layout properties of a unit. [Solution] The unit includes a first planetary gear mechanism, a second planetary gear mechanism, a first engagement element connected to the first planetary gear mechanism, a second engagement element connected to the second planetary gear mechanism, and an actuator driving at least either the first engagement element or the second engagement element. In a radial-direction view, the first engagement element has a portion that overlaps the first planetary gear mechanism. In a radial-direction view, the second engagement element has a portion that overlaps the second planetary gear mechanism. In an axial-direction view, the first planetary gear mechanism has a portion that overlaps the second planetary gear mechanism. The actuator has a portion that is sandwiched between the first engagement element and the second engagement element.

Description

[Technical Field]

[0001] The present invention relates to a unit. [Background technology]

[0002] Patent Document 1 discloses a vehicle drive system in which a rotating electric machine and a transmission are arranged on a first shaft and a differential gear device is arranged on a second shaft. The transmission's speed change gear mechanism includes a first planetary gear mechanism with a first one-way clutch and a second planetary gear mechanism with a second one-way clutch. Both the first one-way clutch and the second one-way clutch are selectable one-way clutches that can be switched between a one-way restricting state that restricts rotation in one direction, a two-way restricting state that restricts rotation in both directions, and a released state that allows rotation in both directions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-175707 Summary of the Invention [Problem to be solved by the invention]

[0004] When a power transmission mechanism of a unit is configured using a plurality of planetary gear mechanisms, it is desirable to achieve an efficient layout in the unit to reduce its size and improve the layout flexibility of the unit.

[0005] The present invention has been made in view of the above problems, and has as its object to improve the layout flexibility of units. [Means for solving the problem]

[0006] A unit according to one aspect of the present invention includes a first planetary gear mechanism, a second planetary gear mechanism, a first engagement element connected to the first planetary gear mechanism, a second engagement element connected to the second planetary gear mechanism, and an actuator that drives at least one of the first engagement element and the second engagement element. When viewed in the radial direction, the first engagement element has a portion that overlaps with the first planetary gear mechanism. When viewed in the radial direction, the second engagement element has a portion that overlaps with the second planetary gear mechanism. When viewed in the axial direction, the first planetary gear mechanism has a portion that overlaps with the second planetary gear mechanism. The actuator has a portion sandwiched between the first engagement element and the second engagement element. [Effects of the Invention]

[0007] According to this aspect, by overlapping each engaging element with the corresponding planetary gear mechanism in the radial direction, the axial dimension can be reduced, improving the layout flexibility of the unit. In this case, a certain amount of clearance is required between the two engaging elements to prevent interference between them, and by making effective use of this space, the layout flexibility of the unit can be further improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of the unit according to this embodiment. [Figure 2] FIG. 2 is a skeleton diagram of the unit. [Figure 3] FIG. 3 is a diagram showing an engagement table of the transmission mechanism. [Figure 4A] FIG. 4A is a first explanatory diagram of the switching mechanism. [Figure 4B] FIG. 4B is a second explanatory diagram of the switching mechanism. [Figure 4C] FIG. 4C is a third explanatory diagram of the switching mechanism. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0010] Fig. 1 is a schematic diagram of a unit 100 according to this embodiment. Fig. 2 is a skeleton diagram of the unit 100.

[0011] Regarding the term "unit," a unit can also be called, for example, a motor unit (a unit having at least a motor) or a power transmission device (a device having at least a power transmission mechanism). A motor is a rotating electric machine having an electric motor function and / or a generator function (at least one of an electric motor function and a generator function). A power transmission mechanism is, for example, a gear mechanism and / or a differential gear mechanism. A device (unit) having a motor and a power transmission mechanism is included in the concepts of both a motor unit and a power transmission device.

[0012] As shown in Fig. 1, the unit 100 includes a housing 10 and a transmission mechanism 20. The unit 100 is mounted on a vehicle, which is an electric vehicle. Power is input to the unit 100 from an MG 40. The MG 40 is a rotating electric machine that functions as a motor generator, and the unit 100 can also be understood as a configuration that further includes the MG 40.

[0013] The housing 10 accommodates the transmission mechanism 20. The transmission mechanism 20 includes a case 21, a rotating shaft 22, a first planetary gear mechanism PGM1, a second planetary gear mechanism PGM2, a first brake B1, a second brake B2, and a clutch CL. The case 21 is cylindrical and fixed to the inner periphery of the housing 10. The first planetary gear mechanism PGM1 is provided within the case 21 via the first brake B1, and the second planetary gear mechanism PGM2 is provided within the case 21 via the second brake B2. The rotating shaft 22 is connected to the MG 40 and rotates by power from the MG 40. The extending direction of the rotating shaft 22 corresponds to the axial direction of the unit 100, and this axial direction refers to the axial direction of the rotating shafts of the components that make up the unit (for example, a motor, a gear mechanism, or a differential gear mechanism).

[0014] The first planetary gear mechanism PGM1 includes a first sun gear S1, a first carrier C1, a first ring gear R1, and a first pinion gear P1. The first sun gear S1 is coaxially fixed to the rotary shaft 22. The first carrier C1 rotatably supports the first pinion gear P1. The first pinion gear P1 meshes with both the first sun gear S1 and the first ring gear R1. The same applies to the second planetary gear mechanism PGM2, which includes a second sun gear S2, a second carrier C2, a second ring gear R2, and a second pinion gear P2.

[0015] The second planetary gear mechanism PGM2 is arranged side by side with the first planetary gear mechanism PGM1 in the axial direction. Therefore, the first planetary gear mechanism PGM1 has a portion that overlaps with the second planetary gear mechanism PGM2 when viewed in the axial direction. "Overlapping" when viewed in a predetermined direction, including radial and axial views, means overlapping in a predetermined direction, and means that multiple elements are lined up in the predetermined direction. For this reason, when a drawing shows multiple elements lined up in a predetermined direction, it can be assumed that the specification contains a statement explaining that the multiple elements overlap when viewed in the predetermined direction.

[0016] The second planetary gear mechanism PGM2 is provided on the side away from the MG40 with respect to the first planetary gear mechanism PGM1. The second carrier C2 is formed integrally with the first ring gear R1 and is connected to the first ring gear R1. The second carrier C2 constitutes the output element of the second planetary gear mechanism PGM2. In contrast, the first carrier C1 constitutes the output element of the first planetary gear mechanism PGM1 and also constitutes the output element of the entire first planetary gear mechanism PGM1 and the second planetary gear mechanism PGM2, and therefore constitutes the output element of the entire transmission mechanism 20.

[0017] The first brake B1 is provided on the outer periphery of the first ring gear R1 and is connected to the first planetary gear mechanism PGM1. The second brake B2 is provided on the outer periphery of the second ring gear R2 and is connected to the second planetary gear mechanism PGM2. Therefore, the first brake B1 has a portion that overlaps with the first planetary gear mechanism PGM1 when viewed in the radial direction, and the second brake B2 has a portion that overlaps with the second planetary gear mechanism PGM2 when viewed in the radial direction.

[0018] The first brake B1 and the second brake B2 are both meshing engagement elements and have a meshing fastening structure. When the first brake B1 is engaged, the first ring gear R1 is fixed to the case 21 together with the second carrier C2. As a result, the first ring gear R1 is fixed to the housing 10 together with the second carrier C2. When the second brake B2 is engaged, the second ring gear R2 is fixed to the case 21. As a result, the second ring gear R2 is fixed to the housing 10. The first brake B1 corresponds to the first engagement element, and the second brake B2 corresponds to the second engagement element.

[0019] The clutch CL is arranged axially alongside the second planetary gear mechanism PGM2 from the side away from the MG40. The clutch CL is provided for the rotary shaft 22 and the second carrier C2, and connects and disconnects them. The clutch CL is a friction engagement element and is a multi-plate clutch. The clutch CL is, for example, an electric clutch, and includes a hub 23, a drum 24, a plurality of drive plates 25, a plurality of driven plates 26, and a piston 27.

[0020] The hub 23 is fixed coaxially to the rotary shaft 22. The hub 23 has an inner cylindrical portion 23a, an outer cylindrical portion 23b, and a bottom wall portion 23c connecting these, and is fixed coaxially to the rotary shaft 22 at the inner cylindrical portion 23a. The drum 24 has a cylindrical portion 24a and a bottom wall portion 24b, and is provided coaxially with the rotary shaft 22. The drum 24 opens in a direction away from the MG 40. The hub 23 is housed within the drum 24, and the outer periphery of the outer cylindrical portion 23b of the hub 23 faces the inner periphery of the cylindrical portion 24a of the drum 24. The drum 24 is fixedly connected to the second carrier C2 at the ring-plate-shaped bottom wall portion 24b.

[0021] A plurality of drive plates 25 are provided on the hub 23. The plurality of drive plates 25 are ring-shaped and are provided on the outer periphery of the outer cylindrical portion 23b so as to be slidable in the axial direction. A plurality of driven plates 26 are provided on the drum 24. The plurality of driven plates 26 are ring-shaped and are provided on the inner periphery of the cylindrical portion 24a so as to be slidable in the axial direction. The plurality of drive plates 25 and the plurality of driven plates 26 are provided alternately arranged one by one in the axial direction.

[0022] The piston 27 is provided inside the drum 24. The piston 27 is slidably provided on the inner periphery of the open end of the drum 24. The piston 27 is, for example, an electric piston driven by an electric actuator of the clutch CL, and engages and disengages the plurality of drive plates 25 and the plurality of driven plates 26 by moving in the engagement direction (to the right in FIG. 1) and the disengagement direction (to the left in FIG. 1) of the clutch CL.

[0023] When the plurality of drive plates 25 and the plurality of driven plates 26 are pushed in the engagement direction by the piston 27 and engage, the clutch CL enters an engaged state. As a result, the rotating shaft 22 and the second carrier C2 are connected via the clutch CL. When the piston 27 moves from this state in the disengagement direction and the plurality of drive plates 25 and the plurality of driven plates 26 are no longer engaged, the clutch CL enters a disengaged state. As a result, the connection between the rotating shaft 22 and the second carrier C2 via the clutch CL is cut off. In the transmission mechanism 20, the following gear stages are formed depending on the engaged / disengaged states of the clutch CL, first brake B1, and second brake B2.

[0024] FIG. 3 is a diagram showing an engagement table for the transmission mechanism 20. As shown in FIG. 3, the transmission mechanism 20 is configured as a three-speed transmission mechanism having three gears: 1st, 2nd, and 3rd, i.e., first, second, and third gears. First gear is achieved by engaging the first brake B1 and disengaging the second brake B2 and the clutch CL. Second gear is achieved by engaging the second brake B2 and disengaging the first brake B1 and the clutch CL. Third gear is achieved by engaging the clutch CL and disengaging the first brake B1 and the second brake B2.

[0025] Returning to Fig. 1, the unit 100 further includes a drive device 30. The drive device 30 is a drive device for the first brake B1 and the second brake B2, and includes an actuator 31 and a worm wheel 32. In Fig. 1, the actuator 31 is schematically indicated by a two-dot dashed line.

[0026] The actuator 31 is an electric motor and has a worm gear 311. The worm gear 311 constitutes the rotation axis of the actuator 31 and meshes with the worm wheel 32. The worm axis of the worm gear 311 and the central axis of the worm wheel 32 are perpendicular to each other, and the worm wheel 32 is provided so as to be rotatable around the axis of the unit 100 by power from the actuator 31. Therefore, the longitudinal direction of the worm gear 311, which is the worm axis direction, intersects with the axial direction of the unit 100.

[0027] The worm gear 311 is provided between the first brake B1 and the second brake B2 in the axial direction of the unit 100. Therefore, the actuator 31 has a portion sandwiched between the first brake B1 and the second brake B2. The worm gear 311 has such a portion in the actuator 31. The worm wheel 32 is provided between the first planetary gear mechanism PGM1 and the second planetary gear mechanism PGM2 in the axial direction of the unit 100.

[0028] The first brake B1 has a first switching mechanism SWM1, and the second brake B2 has a second switching mechanism SWM2. The first switching mechanism SWM1 switches the engagement state of the first brake B1, and the second switching mechanism SWM2 switches the engagement state of the second brake B2.

[0029] 4A to 4C are explanatory diagrams of the switching mechanism SWM. FIG. 4A shows the first switching mechanism SWM1 in a bidirectional restricting state. FIG. 4B shows the first switching mechanism SWM1 in a one-way restricting state. FIG. 4C shows the first switching mechanism SWM1 in a released state. While FIGS. 4A to 4C will be used to explain the first switching mechanism SWM1 as an example of the switching mechanism SWM, the same applies to the second switching mechanism SWM2.

[0030] The first switching mechanism SWM1 includes a first fixed-side member CB1, a first rotating-side member RB1, a first claw CW1, and a first switching unit SW1. The first fixed-side member CB1 is ring-shaped and is fixed to the inner periphery of the case 21. The first claw CW1 is an engaging portion and is attached to the first fixed-side member CB1 at a portion that protrudes radially inward. A plurality of such portions are provided along the circumferential direction, and two first claws CW1 are provided as one set of claws for each such portion. In one set of claws, the first claws CW1 are provided facing opposite directions to correspond to the two rotational directions.

[0031] The first claws CW1 have a structure in which their radially inner tip ends rotate around their radially outer base ends. The first claws CW1 are switched between a locked position, which locks the rotation of the first ring gear R1, and a free position, which frees the rotation, and are biased to the locked position by springs, which are biasing members. Therefore, in the state shown in Figure 4A, each of the first claws CW1 is pressed to the locked position by the spring.

[0032] The first rotating member RB1 is fixed to the outer periphery of the first ring gear R1. The first rotating member RB1 has a ring-like shape and has an engaging portion on its outer periphery consisting of multiple protrusions evenly spaced circumferentially. The first claw CW1 engages with the engaging portion, forming a meshing fastening structure together with the engaging portion. The first claw CW1 prevents rotation of the first ring gear R1 in one rotation direction and allows rotation of the first ring gear R1 in the other rotation direction.

[0033] For example, of the left and right sets of claws in the figure, the first claw CW1 on the left side has its tip portion not retracted radially outward to prevent rotation of the first ring gear R1 in the clockwise direction in the figure, but its tip portion retracted radially outward to allow rotation of the first ring gear R1 in the counterclockwise direction. The first claw CW1 on the right side prevents rotation of the first ring gear R1 in the counterclockwise direction, but allows rotation of the first ring gear R1 in the clockwise direction. As a result, in the bidirectional restricted state shown in FIG. 4A, rotation of the first ring gear R1 in both the left and right directions is restricted. Therefore, the first brake B1 is engaged against bidirectional rotation of the first ring gear R1.

[0034] The first switching unit SW1 has a first switching plate PL1, which switches the position of the first claw CW1. In Figures 4A to 4C, the first switching plate PL1 of the first switching unit SW1 is indicated by a two-dot dashed line. The first switching plate PL1 has a ring shape and is movable in the circumferential direction.

[0035] The first switching plate PL1 has a position corresponding to the bidirectional restricting state shown in Fig. 4A, a position corresponding to the one-way restricting state shown in Fig. 4B, and a position corresponding to the released state shown in Fig. 4C. The first switching plate PL1 is provided on the worm wheel 32 and rotates together with the worm wheel 32. Therefore, the first switching plate PL1 is driven in the circumferential direction by the actuator 31, thereby switching the position of the first switching plate PL1.

[0036] For example, if the first switch plate PL1 is rotated to a fixed position to the right of the position shown in FIG. 4A, the position of the first switch plate PL1 is switched to a position corresponding to the one-way restricting state shown in FIG. 4B. At this time, the first switch SW1 pushes the tip of the left first claw CW1 radially outward against the biasing force of the spring, switching the position of the left first claw CW1 to the free position. As a result, the left first claw CW1 disengages from the engagement portion of the first rotating member RB1, freeing the first ring gear R1 from rotating to the right. Meanwhile, the right first claw CW1 remains engaged with the engagement portion, locking the first ring gear R1 from rotating to the left. Therefore, in this case, the first brake B1 is released from the right-hand rotation of the first ring gear R1 and engaged from the left-hand rotation of the first ring gear R1.

[0037] When the first switch plate PL1 is rotated to a fixed position to the left of the state shown in Fig. 4A, the position of the first switch plate PL1 is switched to a position corresponding to the released state shown in Fig. 4C. At this time, the first switch unit SW1 pushes the tips of both the left and right first claws CW1 radially outward against the biasing force of the spring, switching the positions of both the left and right first claws CW1 to the free position. As a result, the first ring gear R1 is free to rotate in both directions.

[0038] In this way, the actuator 31 drives the first brake B1 by driving the first switching plate PL1. The actuator 31 can also drive the second brake B2 in the same way as the first brake B1.

[0039] Next, the main effects of this embodiment will be described.

[0040] (1) The unit 100 has a first planetary gear mechanism PGM1, a second planetary gear mechanism PGM2, a first brake B1 connected to the first planetary gear mechanism PGM1, a second brake B2 connected to the second planetary gear mechanism PGM2, and an actuator 31 that drives the first brake B1 and the second brake B2. When viewed in the radial direction, the first brake B1 has a portion that overlaps with the first planetary gear mechanism PGM1. When viewed in the radial direction, the second brake B2 has a portion that overlaps with the second planetary gear mechanism PGM2. When viewed in the axial direction, the first planetary gear mechanism PGM1 has a portion that overlaps with the second planetary gear mechanism PGM2. The actuator 31 has a portion sandwiched between the first brake B1 and the second brake B2.

[0041] According to this configuration, the first brake B1 and the second brake B2 are each radially overlapped with the corresponding planetary gear mechanism of the first planetary gear mechanism PGM1 and the second planetary gear mechanism PGM2, thereby reducing the axial dimension, thereby improving the layout flexibility of the unit 100. In this case, a certain amount of clearance is required between the first brake B1 and the second brake B2 to prevent interference between them, and by effectively utilizing this space, the layout flexibility of the unit 100 can be further improved.

[0042] The actuator 31 may be configured to drive the first brake B1 or the second brake B2, and in this case, the same effects can be obtained.

[0043] (2) In the unit 100, the actuator 31 drives both the first brake B1 and the second brake B2. With this configuration, the actuator 31 is shared by the first brake B1 and the second brake B2, thereby reducing the number of parts, and the layout flexibility of the unit 100 can also be improved by reducing the number of parts.

[0044] (3) In the unit 100, the actuator 31 has a worm gear 311. The worm gear 311 has a portion sandwiched between the first brake B1 and the second brake B2, and the longitudinal direction of the worm gear 311 intersects with the axial direction of the unit 100. According to this configuration, when sandwiching the worm gear 311 of the actuator 31 between the first brake B1 and the second brake B2, the longitudinal direction of the worm gear 311 intersects with the axial direction, which can contribute to shortening the unit 100 in the axial direction.

[0045] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above embodiments. [Explanation of symbols]

[0046] 10. Housing 20 Transmission mechanism 22 Rotation axis 30 Drive unit 31 Actuator 311 Worm Gear 100 units B1 First brake (first engagement element) B2 Second brake (second engagement element) CL Clutch PGM1 First planetary gear mechanism PGM2 2nd planetary gear mechanism

Claims

1. a first planetary gear mechanism; a second planetary gear mechanism; a first brake connected to the first planetary gear mechanism; a second brake connected to the second planetary gear mechanism; an actuator that drives both the first brake and the second brake; and the first brake has a portion that overlaps with the first planetary gear mechanism when viewed in a radial direction, the second brake has a portion that overlaps with the second planetary gear mechanism when viewed in a radial direction, When viewed in the axial direction, the first planetary gear mechanism has a portion that overlaps with the second planetary gear mechanism, the actuator has a component sandwiched between the first brake and the second brake in the axial direction as a component different from the first brake and the second brake; unit.

2. 2. The unit of claim 1, the component is a worm gear; the worm gear has a portion sandwiched between the first brake and the second brake, The longitudinal direction of the worm gear intersects with the axial direction. unit.

Images