Drive unit

Abstract

To provide a drive device which enables easy assembly of a sleeve.SOLUTION: One embodiment of a drive device of the invention includes a motor, a power transmission part, a parking mechanism, and a housing having a gear accommodation portion. The parking mechanism has a parking gear, a parking pole, a transmission unit, and a cylindrical sleeve. The transmission unit includes a cam rod and a cam attached to the cam rod to operate the parking pole. The cam is guided by the sleeve. The gear accommodation portion has a breather, and a partition wall portion partitioning a space where the breather opens inside the gear accommodation portion. The gear accommodation portion has a first housing member and a second housing member. The second housing member is provided with a holding recess that opens at one side in an axial direction and holds the sleeve. The first housing member is provided with a retaining wall portion that covers a surface facing the other side in the axial direction of the sleeve. The retaining wall portion is a part of the partition wall portion.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a driving device.

Background Art

[0002] A parking mechanism is mounted on a driving device for driving a vehicle. Patent Document 1 discloses a vehicle parking device that moves a cam member with a parking rod to push out a parking pole toward a parking gear side and locks the parking gear and the parking pole. Patent Document 1 discloses a structure for guiding the cam member with a sleeve member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since a sleeve with a conventional structure was fixed to the inner surface of a housing by bolts or the like, there was a problem that not only the number of parts increased but also the assembly process became complicated.

[0005] In view of the above circumstances, an object of the present invention is to provide a driving device that facilitates the assembly of a sleeve.

Means for Solving the Problems

[0006] One aspect of the drive device of the present invention comprises a motor that rotates about a central axis, a power transmission unit that transmits power from the motor, a parking mechanism, and a housing having a gear housing that accommodates the power transmission unit and the parking mechanism. The power transmission unit has at least one shaft. The parking mechanism has a parking gear provided on the outer circumferential surface of the shaft, a parking pawl provided with a protrusion that meshes with the parking gear, a transmission unit that transmits power to the parking pawl, and a cylindrical sleeve. The transmission unit has a cam rod that drives along the axial direction of the central axis, and a cam attached to the cam rod that operates the parking pawl. The cam is guided by the sleeve. The gear housing is provided with a breather that connects the inside and outside of the gear housing, and a partition wall that divides the space inside the gear housing through which the breather opens. The gear housing comprises a first housing member and a second housing member positioned on one axial side of the first housing member and connected to the first housing member. The second housing member is provided with a retaining recess that opens on one axial side and holds the sleeve. The first housing member is provided with a retaining wall that covers the other axial side of the sleeve. The retaining wall is part of the partition wall. [Effects of the Invention]

[0007] According to one aspect of the present invention, a drive device that facilitates the assembly of sleeves can be provided. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a perspective view of a drive device according to one embodiment. [Figure 2] Figure 2 is a conceptual diagram of a drive device according to one embodiment. [Figure 3] Figure 3 is a front view of the gear housing in one embodiment. [Figure 4] Figure 4 is a front view of a breather chamber in one embodiment. [Figure 5]Figure 5 is a partial cross-sectional view of a drive device according to one embodiment. [Figure 6] Figure 6 is a perspective view of a parking mechanism according to one embodiment. [Figure 7] Figure 7 is a partial cross-sectional perspective view of a drive device according to one embodiment. [Figure 8] Figure 8 is an exploded perspective view of the sleeve and housing of one embodiment. [Modes for carrying out the invention]

[0009] In the following explanation, the direction of gravity is defined and explained based on the positional relationship when the drive unit 1 is mounted on a vehicle located on a horizontal road surface. In addition, the XYZ coordinate system is shown as a three-dimensional Cartesian coordinate system in the drawings as appropriate.

[0010] In the XYZ coordinate system, the Z-axis direction represents the vertical direction (i.e., up and down direction), with the +Z direction being the upper side (opposite to the direction of gravity) and the -Z direction being the lower side (direction of gravity). The X-axis direction is perpendicular to the Z-axis direction and indicates the front-rear direction of the vehicle on which the drive unit 1 is mounted. In the following embodiments, the side pointed to by the X-axis arrow (+X side) is the front of the vehicle, and the side opposite to the direction pointed to by the X-axis arrow (-X side) is the rear of the vehicle. The Y-axis direction is perpendicular to both the X-axis and Z-axis directions and indicates the width direction (left-right direction) of the vehicle. In the following embodiments, the side pointed to by the Y-axis arrow (+Y side) is the left side of the vehicle, and the side opposite to the direction pointed to by the Y-axis arrow (-Y side) is the right side of the vehicle. The front-rear and left-right directions are horizontal directions perpendicular to the vertical direction.

[0011] In the following explanation, unless otherwise specified, the direction parallel to the central axis J1 of motor 2 (the Y-axis direction) will be simply referred to as the "axial direction," the radial direction centered on the central axis J1 will be simply referred to as the "radial direction," and the circumferential direction centered on the central axis J1, i.e., the direction around the axis of the central axis J1, will be simply referred to as the "circumferential direction." However, the above "parallel direction" also includes approximately parallel directions. Furthermore, in the following explanation, within the axial direction of the central axis J1, the +Y direction may be simply referred to as one side of the axial direction, and the -Y direction may be simply referred to as the other side of the axial direction.

[0012] <Drive system> Figure 1 is a perspective view of the drive unit 1 of this embodiment. Figure 2 is a conceptual diagram of the drive unit 1 of this embodiment. The drive unit 1 of this embodiment is installed in vehicles that use a motor as a power source, such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHVs), and electric vehicles (EVs), and is used as a power source for such vehicles.

[0013] As shown in Figure 2, the drive unit 1 comprises a motor 2, a power transmission unit 4, a parking device 5, an inverter 7, and a housing 6. The housing 6 houses the motor 2, the power transmission unit 4, the parking device 5, and the inverter 7. Inside the housing 6, the motor 2, the power transmission unit 4, and the inverter 7 are arranged on the central axis J1.

[0014] <motor> The motor 2 in this embodiment is an inner-rotor type three-phase AC motor. The motor 2 combines the functions of both an electric motor and a generator. Note that the configuration of the motor 2 is not limited to this embodiment, and may be, for example, a four-phase or more AC motor.

[0015] Motor 2 rotates about a central axis J1 that extends horizontally. Motor 2 comprises a rotor 20 and a stator 30 that is radially opposite to the rotor 20. Motor 2 in this embodiment is an inner rotor type motor in which the rotor 20 is positioned inside the stator 30.

[0016] The rotor 20 rotates about the central axis J1. The rotor 20 includes a first shaft 21, a rotor core 24 fixed to the outer peripheral surface of the first shaft 21, and a rotor magnet (not shown) fixed to the rotor core 24. The torque of the rotor 20 is transmitted to the power transmission unit 4. The first shaft 21 extends along the axial direction about the central axis J1. Both ends of the first shaft 21 are rotatably supported by the housing 6 via bearings.

[0017] The stator 30 is held by the housing 6. The stator 30 surrounds the rotor 20 from the radially outer side. The stator 30 includes an annular stator core 32 centered on the central axis J1, a coil 31 attached to the stator core 32, and an insulator (not shown) interposed between the stator core 32 and the coil 31. The stator core 32 has a plurality of magnetic pole teeth (not shown) extending radially inward from the inner peripheral surface of the annular yoke. Coil wires are arranged between the magnetic pole teeth. The coil wires located within the gaps between adjacent magnetic pole teeth constitute the coil 31. The insulator is made of an insulating material.

[0018] <Inverter> The inverter 7 is electrically connected to the motor 2. The inverter 7 is connected to a battery (not shown) mounted on the vehicle, converts the DC current supplied from the battery into an AC current, and supplies it to the motor 2. Also, the inverter 7 controls the motor 2. The inverter 7 of the present embodiment is arranged on one axial side (+Y side) with respect to the motor 2. According to the present embodiment, the drive device 1 can be reduced in size in the radial direction as compared with the case where the inverter 7 is arranged outside the motor 2 in the radial direction.

[0019] <Power transmission unit> As shown in FIG. 2, the power transmission unit 4 is arranged on the other axial side (-Y side) with respect to the motor 2. The power transmission unit 4 is connected to the rotor 20 to transmit the power of the motor 2 and output it to the output shaft 47. The power transmission unit 4 includes a reduction gear 4a and a differential gear 4b. That is, the drive device 1 includes the reduction gear 4a and the differential gear 4b.

[0020] The torque output from motor 2 is transmitted to differential 4b via reduction gear 4a. Reduction gear 4a is a parallel-axis gear type reduction gear in which the rotation axes of each gear are arranged in parallel. When the vehicle turns, differential 4b absorbs the speed difference between the left and right wheels and transmits the same torque to both wheels.

[0021] The reduction gear 4a has a second shaft (shaft) 44, a first gear 41, and a second gear section 48. That is, the drive unit 1 has a second shaft 44, a first gear 41, and a second gear section 48. The second gear section 48 also has a third shaft 45, a large-diameter gear 42, and a small-diameter gear 43. The differential gear 4b has a third gear 46g, a differential case 46, and a differential mechanism section 46c located inside the differential case 46. That is, the power transmission unit 4 has a plurality of gears 41, 42, 43, and 46g.

[0022] The second shaft 44 extends axially around the central axis J1. The second shaft 44 is positioned coaxially with the first shaft 21. The second shaft 44 is connected to the other axial end (-Y side) of the first shaft 21 at one axial end (+Y side). The second shaft 44 rotates together with the first shaft 21 around the central axis J1. That is, the second shaft 44 rotates around the central axis J1 with the power of the motor 2.

[0023] The first gear 41 is provided on the outer circumferential surface of the second shaft 44. The first gear 41 rotates together with the second shaft 44 around the central axis J1.

[0024] Each part of the second gear section 48 (third shaft 45, large-diameter gear 42, and small-diameter gear 43) is fixed to each other. The second gear section 48 rotates about an intermediate axis J2 that is parallel to the central axis J1. The third shaft 45 extends axially about the intermediate axis J2. The large-diameter gear 42 and the small-diameter gear 43 are arranged side by side in the axial direction. The small-diameter gear 43 is positioned closer to the motor 2 than the large-diameter gear 42 in the axial direction (i.e., one side in the axial direction). The large-diameter gear 42 and the small-diameter gear 43 are provided on the outer circumferential surface of the third shaft 45.

[0025] The large-diameter gear 42 meshes with the first gear 41. As a result, the large-diameter gear 42 rotates around the intermediate axis J2. The small-diameter gear 43 has a smaller diameter than the large-diameter gear 42. The small-diameter gear 43 rotates together with the large-diameter gear 42 around the intermediate axis J2.

[0026] The third gear 46g meshes with the small-diameter gear 43. The third gear 46g rotates around the differential axis J3, which is parallel to the central axis J1. Torque output from the motor 2 is transmitted to the third gear 46g via the reduction gear 4a. The third gear 46g is fixed to the differential case 46.

[0027] The differential case 46 has a case portion 46b that houses the differential mechanism 46c inside, and differential case shafts 46a that protrude from the case portion 46b in the axial direction, on one side and the other side, respectively. The differential case shafts 46a are cylindrical in shape and extend axially around the differential axis J3. The third gear 46g is provided on the outer circumferential surface of the differential case shaft 46a. The differential case shaft 46a rotates together with the third gear 46g around the differential axis J3.

[0028] A pair of output shafts 47 are connected to the differential 4b. The pair of output shafts 47 project axially from the differential case 46 of the differential 4b, on one and the other sides. The output shafts 47 are positioned inside the differential case shaft 46a. The output shafts 47 are rotatably supported on the inner circumferential surface of the differential case shaft 46a via bearings.

[0029] The torque output from motor 2 is, Reducer 4a The power is transmitted to the third gear 46g of the differential 4b via the second shaft 44, first gear 41, large-diameter gear 42, third shaft 45, and small-diameter gear 43, and output to the output shaft 47 via the differential mechanism 46c of the differential 4b. The multiple gears 41, 42, 43, and 46g of the power transmission unit 4 transmit the power of the motor 2 in the order of the second shaft 44, the third shaft 45, and the differential case shaft 46a.

[0030] <Housing> The housing 6 comprises an inverter holder 6A, a housing body 6B, a gear cover 6C, a water jacket 6D, and a bearing holder 6E. The inverter holder 6A, housing body 6B, gear cover 6C, water jacket 6D, and bearing holder 6E are each separate components. The inverter holder 6A is located on one axial side (+Y side) of the housing body 6B. The gear cover 6C is located on the other axial side (-Y side) of the housing body 6B. The water jacket 6D and bearing holder 6E are located inside the housing body 6B.

[0031] The housing body 6B houses the motor 2 and opens to one side in the axial direction (+Y side). The housing body 6B has a cylindrical outer cylinder portion 65 centered on the central axis J1, a partition wall portion 66 positioned on the other side in the axial direction (-Y side) of the outer cylinder portion 65 and covering the opening on the other side in the axial direction of the outer cylinder portion 65, and a first gear peripheral wall portion 66a extending from the outer edge of the partition wall portion 66 to the other side in the axial direction (-Y side).

[0032] In this specification, the partition wall 66 refers to the entire wall portion extending along a plane perpendicular to the axial direction between the motor 2 and the power transmission unit 4. In this specification, the partition wall 66 includes not only the portion separating the spaces housing the motor 2 and the power transmission unit 4 within the housing 6, but also the portion extending radially outward from the space housing the motor 2 or the power transmission unit 4.

[0033] A shaft insertion hole 65h is provided in the partition wall 66. A bearing supporting the first shaft 21, a bearing supporting the second shaft 44, and a sealing member are arranged in the shaft insertion hole 65h. The first shaft 21 and the second shaft 44 are connected to each other inside the shaft insertion hole 65h. The sealing member is positioned between the two bearings in the axial direction. The sealing member seals the space between the inner circumferential surface of the shaft insertion hole 65h and the outer circumferential surface of the second shaft 44. Note that the first shaft 21 and the second shaft 44 may be a single component.

[0034] The outer cylindrical portion 65 of the housing body 6B has a motor peripheral wall portion 65e that surrounds the motor 2 from the radial outside and an inverter peripheral wall portion 65f that surrounds a part of the inverter 7 from the radial outside. The motor peripheral wall portion 65e supports the stator 30 via the water jacket 6D. The inverter peripheral wall portion 65f is located on one axial side (+Y side) of the motor peripheral wall portion 65e.

[0035] The gear cover 6C is positioned on the other axial side (-Y side) of the housing body 6B. The gear cover 6C has an opposing wall portion 67 that faces the partition wall portion 66, and a second gear peripheral wall portion 67a that extends from the outer edge of the opposing wall portion 67 to one axial side (+Y side). The end face of the second gear peripheral wall portion 67a on one axial side (+Y side) is fastened to the end face of the first gear peripheral wall portion 66a of the housing body 6B on the other axial side (-Y side).

[0036] The inverter holder 6A holds the inverter 7. The inverter holder 6A covers the opening on one axial side (+Y side) of the outer cylindrical portion 65 of the housing body 6B. The inverter holder 6A is provided with a first flow path 91 for cooling the inverter 7.

[0037] The water jacket 6D has a cylindrical inner section 64 centered on the central axis J1. The inner section 64 surrounds the stator 30 from the radially outer side. The inner diameter of the inner section 64 is approximately the same as the outer diameter of the stator core 32. The inner circumferential surface of the inner section 64 is in contact with the outer circumferential surface of the stator 30. The inner section 64 is also surrounded from the radially inner side by the outer section 65. The outer diameter of the inner section 64 is smaller than the inner diameter of the outer section 65 of the housing body 6B. A gap is provided between the inner section 64 and the outer section 65 that functions as a third flow path section 93.

[0038] The bearing holder 6E is located inside the housing body 6B on one axial side (+Y side) of the motor 2. The bearing holder 6E is fixed to the end face of the water jacket 6D on one axial side (+Y side). The bearing holder 6E holds the bearing that rotatably supports the rotor 20. In this embodiment, the bearing holder 6E is a plate-shaped member made of a metal material. The bearing holder 6E is formed, for example, by press working. However, the configuration and manufacturing method of the bearing holder 6E are not limited to this embodiment.

[0039] The housing 6 has a motor housing 81, a gear housing 82, and an inverter housing 83. The gear housing 82 is located on the other axial side (-Y side) of the motor housing 81. The inverter housing 83 is located on one axial side (+Y side) of the motor housing 81. The motor housing 81, gear housing 82, and inverter housing 83 are composed of an inverter holder 6A, a housing body 6B, a gear cover 6C, and a water jacket 6D.

[0040] The motor housing 81 has a motor peripheral wall portion 65e of the housing body 6B and an inner cylindrical portion 64 of the water jacket 6D. A motor chamber breather 63 is provided in the motor housing 81. The motor chamber breather 63 communicates the inside and outside of the motor housing 81. The motor chamber breather 63 prevents the pressure inside the motor housing 81 from becoming too high.

[0041] The inverter housing section 83 is composed of the inverter peripheral wall section 65f of the housing body 6B and the inverter holder 6A. The inverter 7 is supported by the inverter holder 6A. A portion of the inverter 7 is positioned radially inward of the inverter peripheral wall section 65f.

[0042] The gear housing 82 houses the power transmission unit 4 and the parking mechanism 50, which will be described later. That is, the housing 6 houses the second shaft 44, the first gear 41, the second gear unit 48, the differential 4b, and the parking mechanism 50 in the gear housing 82. The gear housing 82 is composed of the partition wall 66 and the first gear peripheral wall 66a of the housing body 6B, and the opposing wall 67 and the second gear peripheral wall 67a of the gear cover 6C. In the following description, "inside the gear housing 82" (or "within the gear housing 82") means the space sandwiched between the partition wall 66 and the opposing wall 67 in the axial direction, and surrounded by the first gear peripheral wall 66a and the second gear peripheral wall 67a in the radial direction.

[0043] A fluid O is stored inside the gear housing 82. The fluid O is, for example, oil. In this embodiment, the fluid O is used as a coolant to cool the motor 2. The fluid O is also used as a lubricant for the power transmission section 4 and the bearings. As the fluid O, it is preferable to use an oil equivalent to an automatic transmission fluid (ATF) with relatively low viscosity in order to perform the functions of both a coolant and a lubricant.

[0044] As shown in Figure 1, the opposing wall portion 67 of the gear housing 82 is provided with a first projection (projection) 10 that protrudes in the other axial direction (-Y side). That is, the housing 6 has a first projection 10 that protrudes in the axial direction. The first projection 10 also protrudes outward from the housing 6. The first projection 10 protrudes in the other axial direction (-Y side) compared to other parts of the opposing wall portion 67. That is, the first projection 10 protrudes in the other axial direction (-Y side) than the portion of the gear housing 82 that houses the first gear 41, the second gear portion 48, and the differential gear 4b.

[0045] The first protrusion 10 is part of the opposing wall 67 and protrudes outward to widen the internal space of the gear housing 82. Inside the first protrusion 10 is a first housing space (housing space) 10a. The first housing space 10a is the internal space of the portion of the opposing wall 67 that is recessed in the other axial direction (-Y side) when viewed from one axial side (+Y side), and widens the internal space of the gear housing 82 in the other axial direction (-Y side). In addition, an actuator 59 that transmits power to the parking mechanism 50 is fixed to the upper surface of the first protrusion 10.

[0046] On the surface of the opposing wall portion 67 facing the other axial side (-Y side), there are a plurality of mounting portions 67b and a plurality of straight ribs 67d. In this embodiment, the mounting portions 67b are boss-shaped and have bolt holes 67c. Bolts for fixing the housing 6 to the vehicle are fastened to the mounting portions 67b. The plurality of straight ribs 67d connect the plurality of mounting portions 67b to each other. Two of the plurality of straight ribs 67d intersect each other.

[0047] In this embodiment, the protruding height of the mounting portion 67b and the straight rib 67d is greater than the protruding height of the first protruding portion 10. That is, the ends of the mounting portion 67b and the straight rib 67d on the other axial side (-Y side) are located further to the other axial side (-Y side) than the end of the first protruding portion 10 on the other axial side (-Y side). As a result, the mounting portion 67b and the straight rib 67d protect the first protruding portion 10 from strong impacts during an accident.

[0048] Figure 3 is a front view of the gear housing 82 with the gear cover 6C removed. The gear housing 82 has a top surface 82t that covers the internal space of the gear housing 82 from above, a bottom surface 82m that covers it from below, a front surface 82f that covers it from the front side (+X side) of the vehicle, and a portion that covers it from the rear side of the vehicle.

[0049] A catch tank 84 is provided inside the gear housing 82. The catch tank 84 opens upwards. In this embodiment, the catch tank 84 is rib-shaped, protruding axially from the partition wall 66. A portion of the catch tank 84 is connected to the top surface 82t.

[0050] The catch tank 84 receives the fluid O scooped up by each gear of the power transmission unit 4 (for example, the third gear 46g and the large-diameter gear 42) inside the gear housing 82. The catch tank 84 supplies the fluid O to bearings and the like through holes (not shown).

[0051] A breather 8 is provided in the gear housing 82. The breather 8 is located on the top surface 82t of the gear housing 82. In other words, the breather 8 is located at the top of the gear housing 82. The breather 8 communicates the inside and outside of the gear housing 82 and adjusts the internal pressure of the gear housing 82.

[0052] The breather 8 has a hole 8a and a pipe 8b attached to the hole 8a. The hole 8a is provided on the top surface 82t. In this embodiment, the hole 8a is a circular hole that extends linearly along the vertical direction. The inner circumferential surface of the hole 8a is provided with female threads. The outer circumferential surface of the pipe 8b is provided with male threads that can be inserted into the female threads of the hole 8a. The pipe 8b is inserted into and fixed in the hole 8a. The pipe 8b is tubular with open ends and connects the inside and outside of the gear housing 82. A filter may be provided inside the pipe 8b. A hose may also be connected to the end of the pipe 8b.

[0053] The gear housing 82 is provided with a first partition wall 89 and a second partition wall 86. The first partition wall 89 and the second partition wall 86 are located inside the gear housing 82. The first partition wall 89 and the second partition wall 86 extend along the axial direction. The first partition wall 89 partitions the space inside the gear housing 82 through which the breather 8 opens (hereinafter referred to as the breather chamber R8). The second partition wall 86 is located inside the breather chamber R8. The second partition wall 86 provides a complex path inside the breather chamber R8.

[0054] According to this embodiment, by providing a breather chamber R8 surrounded by a first partition wall 89 within the gear housing 82, it is possible to suppress the fluid O scattered within the gear housing 82 from reaching the opening of the breather 8. This prevents the fluid O from flowing out of the housing 6.

[0055] According to this embodiment, a second partition wall 86 is provided inside the breather chamber R8. The second partition wall 86 further surrounds the opening of the breather 8 inside the breather chamber R8. By providing the second partition wall 86, a labyrinth structure can be formed inside the breather chamber R8. The second partition wall 86 can suppress the reach of the breather 8 even if scattered fluid O enters the breather chamber R8.

[0056] Furthermore, the function of the second compartment wall 86 can also be described as further partitioning the interior of the breather chamber R8. That is, the second compartment wall 86 partitions the space inside the gear housing 82 through which the breather 8 opens.

[0057] Figure 4 is a front view of the gear housing 82 near the breather chamber R8. The breather chamber R8 is located at the front (+X) end of the gear housing 82. The breather chamber R8 is also located at the upper end of the gear housing 82. The breather chamber R8 is enclosed by the front portion 82f and top portion 82t of the gear housing 82 and the first compartment wall portion 89.

[0058] The first compartment wall 89 has a first vertical compartment wall 89a extending downward from the top surface 82t of the gear housing 82, and a first horizontal compartment wall 89b extending from the lower end of the first vertical compartment wall 89a toward the front of the vehicle (+X side). The first horizontal compartment wall 89b slopes downward as it faces toward the front of the vehicle (+X side). The front end of the first horizontal compartment wall 89b faces the front surface 82f of the gear housing 82 with a gap between them. This gap connects the breather chamber R8 to other spaces within the gear housing 82. The first horizontal compartment wall 89b is located directly below the opening of the hole 8a of the breather 8.

[0059] The second compartment wall 86 has a second vertical compartment wall 86a extending downward from the top surface 82t of the gear housing 82, and a second horizontal compartment wall 86b extending from the lower end of the second vertical compartment wall 86a toward the rear of the vehicle (-X side). The second horizontal compartment wall 86b is slightly inclined downward as it approaches the rear of the vehicle (-X side). The rear end of the second horizontal compartment wall 86b faces the first vertical compartment wall 89a with a gap between them. In the vertical direction, the second horizontal compartment wall 86b is positioned between the opening of the hole 8a of the breather 8 and the first horizontal compartment wall 89b.

[0060] The first compartment wall 89 and the second compartment wall 86 are each composed of a pair of rib-shaped wall portions that protrude in opposite directions from the housing body 6B and the gear cover 6C, respectively, and abut against each other. Here, of the wall portions constituting the first compartment wall 89, the wall portion that protrudes from the housing body 6B side to the other axial side (-Y side) is called the first wall portion 87, and the wall portion that protrudes from the gear cover 6C side to one axial side (+Y side) is called the second wall portion 88. That is, the first compartment wall 89 has a first wall portion 87 which is part of the housing body 6B and a second wall portion 88 which is part of the gear cover 6C. Similarly, of the wall portions constituting the second compartment wall 86, the wall portion that protrudes from the housing body 6B side to the other axial side (-Y side) is called the third wall portion 86P, and the wall portion that protrudes from the gear cover 6C side to one axial side (+Y side) is called the fourth wall portion 86Q. In other words, the second compartment wall 86 has a third wall 86P which is part of the housing body 6B and a fourth wall 86Q which is part of the gear cover 6C. The mating surfaces of the first wall 87 and the second wall 88, and the mating surfaces of the third wall 86P and the fourth wall 86Q are each located on the same plane as the fastening surfaces of the housing body 6B and the gear cover 6C.

[0061] A portion of the first wall 87 surrounds the outer circumference of the sleeve 56 of the parking mechanism 50, which will be described later. Here, the portion of the first wall 87 that surrounds the outer circumference of the sleeve 56 is called the sleeve guide portion 87a. A notch 87t is provided in the sleeve guide portion 87a.

[0062] An extension wall 87e is connected to the first wall 87. That is, an extension wall 87e is provided in the bulkhead 66 of the housing body 6B. The extension wall 87e extends from the sleeve guide 87a toward the rear side of the vehicle (-X side). The extension wall 87e extends in an arc shape along the outer surface of the sleeve 56.

[0063] The upper end of the first wall 87 connects to the top surface 82t of the gear housing 82. On the other hand, the upper end of the second wall 88 does not connect to the top surface 82t. The upper end of the second wall 88 faces the top surface 82t in the vertical direction with a gap in between. Therefore, a partial gap is provided between the first compartment wall 89 and the top surface 82t. This ensures a more reliable passage to the breather chamber R8.

[0064] The upper end of the third wall 86P connects to the top surface 82t of the gear housing 82. On the other hand, the upper end of the fourth wall 86Q does not connect to the top surface 82t. The upper end of the fourth wall 86Q faces the top surface 82t in the vertical direction with a gap in between. A partial gap is provided between the second compartment wall 86 and the top surface 82t. This reliably prevents the area around the opening of the breather 8 from being completely closed.

[0065] As shown in Figure 2, the housing 6 is provided with a flow path 90 through which cooling water L flows. The cooling water L is, for example, water. The flow path 90 has an external pipe 97 that passes outside the housing 6, and a first flow path section 91, a second flow path section 92, a third flow path section 93, and a fourth flow path section 94 that pass inside the housing 6.

[0066] External piping 97 is piping connected to housing 6. A radiator (not shown) for cooling the cooling water L is located in the path of external piping 97. The cooling water L flows inside housing 6 in the order of first flow path section 91, second flow path section 92, third flow path section 93, and fourth flow path section 94. The first flow path section 91 is provided in the inverter housing section 83. The first flow path section 91 is connected to external piping 97. The cooling water L flowing through the first flow path section 91 cools the inverter 7. The second flow path section 92 is provided in the outer cylindrical section 65 of housing body 6B. The second flow path section 92 connects the first flow path section 91 and the third flow path section 93. The third flow path section 93 is located between the outer cylindrical section 65 of housing body 6B and the inner cylindrical section 64 of water jacket 6D. A spiral projection is provided on the outer circumferential surface of the inner cylindrical section 64. As a result, the third flow channel 93 extends spirally along the circumferential direction. The cooling water L flowing through the third flow channel 93 cools the stator 30. The fourth flow channel 94 is provided in the outer cylindrical portion 65 of the housing body 6B. The fourth flow channel 94 connects the third flow channel 93 to the external piping 97.

[0067] <Parking device> The parking device 5 is located inside the gear housing 82. The parking device 5 locks the rotation of one shaft (the second shaft 44 in this embodiment) of the power transmission unit 4.

[0068] The parking device 5 includes an actuator 59 and a parking mechanism 50 driven by the actuator 59. That is, the drive device 1 includes the parking mechanism 50 and the actuator 59. The actuator 59 is located outside the housing 6. On the other hand, the parking mechanism 50 is located inside the housing 6 (more specifically, the gear housing 82).

[0069] <Actuator> The actuator 59 operates the parking mechanism 50. The actuator 59 switches the parking mechanism 50 between a locked state that prevents the rotation of the second shaft 44 and an unlocked state that allows the rotation of the second shaft 44. The parking device 5 is in the locked state when the vehicle's gear is in parking, and in the unlocked state when the vehicle's gear is not in parking. When the vehicle's gear is not in parking, for example, this includes when the vehicle's gear is in drive, neutral, reverse, etc.

[0070] Figure 5 is a cross-sectional view of the drive unit 1 at the connection point between the actuator 59 and the parking mechanism 50 in this embodiment. The actuator 59 has a rotating part 58 and a housing 59h. Although not shown in the figures, the actuator 59 also has a drive motor and a transmission mechanism located inside the housing 59h.

[0071] The rotating part 58 rotates around the drive axis J5 by the power of the drive motor. The rotating part 58 has a cylindrical section 58a, a bottom section 58c, and a first surface 58b.

[0072] In the following description, the actuator 59 and the rotating shaft 57 connected to the actuator 59 will be described with reference to the drive axis J5. In this embodiment, one axial side of the drive axis J5 means the lower side (-Z side), and the other axial side of the drive axis J5 means the upper side (+Z side).

[0073] The cylindrical portion 58a is cylindrical with a drive axis J5 extending vertically as its center. The cylindrical portion 58a opens on one axial side (lower side) of the drive axis J5. A bottom portion 58c is provided on the other axial side (upper side) of the cylindrical portion 58a with respect to the drive axis J5. Multiple spline grooves 58f extending in the axial direction of the drive axis J5 are provided on the inner circumferential surface of the cylindrical portion 58a. In other words, the cylindrical portion 58a is provided with spline grooves 58f. The rotating shaft 57 of the parking mechanism 50 is inserted into and connected to the cylindrical portion 58a from below. The actuator 59 transmits power to the parking mechanism 50 in the cylindrical portion 58a.

[0074] The first surface 58b faces one axial side (downward) of the drive axis J5. The first surface 58b is the lower end surface of the cylindrical portion 58a. The first surface 58b is located at the opening edge of the cylindrical portion 58a. The first surface 58b is an annular surface surrounding the drive axis J5.

[0075] The housing 59h has a support cylinder 59k surrounding the cylindrical portion 58a. The support cylinder 59k is cylindrical with the drive axis J5 as its center. The support cylinder 59k rotatably supports the cylindrical portion 58a. An O-ring is placed between the inner circumferential surface of the support cylinder 59k and the outer circumferential surface of the cylindrical portion 58a to prevent liquid from entering the inside of the housing 59h.

[0076] The actuator 59 is mounted on the upper side of the first projection 10 of the housing 6. The first projection 10 has an upper wall (first wall) 11 and a lower wall (second wall) 12 that face each other in the vertical direction. The upper wall 11 and the lower wall 12 extend along the horizontal direction.

[0077] A through-hole 19a is provided in the upper wall 11, centered on the drive axis J5. The through-hole 19a penetrates the upper wall 11 in the vertical direction. A connecting cylindrical portion 19 is also provided in the upper wall 11, extending upward from the upper surface of the upper wall 11. The connecting cylindrical portion 19 surrounds the through-hole 19a from the radially outer side of the drive axis J5. The diameter of the inner circumferential surface of the connecting cylindrical portion 19 is larger than the diameter of the through-hole 19a. The support cylinder 59k of the actuator 59 is inserted into the connecting cylindrical portion 19 from the outside of the housing 6. An O-ring is placed between the inner circumferential surface of the connecting cylindrical portion 19 and the outer circumferential surface of the support cylinder 59k to prevent liquid from entering the inside of the housing 6.

[0078] The connecting cylinder portion 19 surrounds the rotating shaft 57 of the parking mechanism 50 from the radially outer side of the drive axis J5. A gasket 19g is fixed to the inner circumferential surface of the connecting cylinder portion 19. The inner circumferential surface of the gasket 19g contacts the outer circumferential surface of the rotating shaft 57 that is inserted into the connecting cylinder portion 19. The gasket 19g seals the gap between the inner circumferential surface of the connecting cylinder portion 19 and the outer circumferential surface of the rotating shaft 57.

[0079] <Parking mechanism> Figure 6 is a perspective view of the parking mechanism 50. The parking mechanism 50 includes a parking gear 51, a parking pawl 52, a transmission unit 50A that transmits power to the parking pawl 52, and a cylindrical sleeve 56. The transmission unit 50A also includes a pawl shaft 50t, a cam rod 54, a cam 53, a coil spring 50d, a flange 55, and a rotating shaft 57. The transmission unit 50A receives power from the actuator 59 at the rotating shaft 57 and transmits power to the parking pawl 52 at the cam 53.

[0080] As shown in Figure 5, the rotating shaft 57, the flange 55, and a portion of the cam rod 54 are housed in the first housing space 10a inside the first projection 10. That is, at least a portion of the transmission section 50A is housed in the first housing space 10a.

[0081] As shown in Figure 2, the gear housing 82 has a first protrusion 10. The first housing space 10a inside the first protrusion 10 houses at least a part of the transmission section 50A of the parking mechanism 50. According to this embodiment, instead of enlarging the gear housing 82 in one direction to secure the housing volume of the parking mechanism 50, the overall external shape of the gear housing 82 can be made smaller by locally widening a part of it to match the shape of the parking mechanism 50. In addition, since the first protrusion 10 in this embodiment protrudes in the axial direction (Y-axis direction), it is possible to suppress an increase in the projected area in the axial direction of the drive unit 1. For this reason, the housing space of the drive unit 1 inside the vehicle does not become large.

[0082] As shown in Figure 2, the first protrusion 10 of this embodiment overlaps with at least a portion of the large-diameter gear 42 when viewed from a direction perpendicular to the axial direction. In other words, the axial position of the first protrusion 10 overlaps with the axial position of the large-diameter gear 42. According to this embodiment, by arranging the first protrusion 10 to overlap with the gear of the power transmission unit 4 in the axial direction, it is possible to suppress the axial enlargement of the gear housing 82 relative to the protrusion amount of the first protrusion 10.

[0083] <Rotating shaft> As shown in Figure 5, the rotating shaft 57 is cylindrical with the drive axis J5 as its center. The rotating shaft 57 has a first end 57a located on the other axial side (upper side) of the drive axis J5 and a second end 57b located on the one axial side (lower side). The rotating shaft 57 is connected to the actuator 59. The rotating shaft 57 rotates around the drive axis J5 by the power of the actuator 59.

[0084] The rotating shaft 57 extends both inside and outside the housing 6. The first end 57a is located outside the housing 6, while the second end 57b is located inside the housing 6. In other words, at least a portion of the rotating shaft 57 is located inside the housing 6. The rotating shaft 57 is connected to the actuator 59 outside the housing 6 and to the flange 55 inside the housing 6.

[0085] Multiple spline projections 57m extending in the axial direction of the drive axis J5 are provided on the outer circumferential surface of the first end portion 57a. The first end portion 57a ​​is inserted into the cylindrical portion 58a of the actuator 59. As a result, the spline projections 57m of the first end portion 57a ​​engage with the spline grooves 58f of the cylindrical portion 58a, and the rotating shaft 57 is connected to the cylindrical portion 58a. Since the connection between the rotating shaft 57 and the cylindrical portion 58a is a spline fit, it allows relative movement of the drive axis J5 in the axial direction.

[0086] The first end 57a has a smaller outer diameter compared to the rest of the rotating shaft 57. Here, the portion of the rotating shaft 57 excluding the first end 57a is called the large-diameter portion 57c. That is, the rotating shaft 57 has a large-diameter portion 57c with a larger diameter than the first end 57a. The second end 57b is part of the large-diameter portion 57c.

[0087] A stepped second surface 57t is provided between the first end portion 57a ​​and the large-diameter portion 57c. The second surface 57t is the upper end surface of the large-diameter portion 57c. The second surface 57t is also an annular surface surrounding the drive axis J5. The second surface 57t faces the other side (upper side) in the axial direction of the drive axis J5. In the axial direction of the drive axis J5, the second surface 57t faces the first surface 58b of the actuator 59.

[0088] Between the first end portion 57a ​​and the large-diameter portion 57c, a recessed portion 57g is provided, having an outer diameter smaller than that of the first end portion 57a. The recessed portion 57g extends in a groove-like shape along the circumferential direction. Generally, it is difficult to form a complete shape for a spline projection 57m all the way to its root in the axial direction. According to this embodiment, by providing the recessed portion 57g, the incomplete spline shape at the root of the spline projection 57m can be eliminated.

[0089] The large-diameter portion 57c is provided with a supported portion 57d that is rotatably supported by the upper wall 11 of the housing 6. That is, the rotating shaft 57 has a supported portion 57d. The supported portion 57d contacts the inner surface of the through hole 19a on its outer circumferential surface. The through hole 19a is circular in plan view, centered on the drive axis J5. The inner diameter of the through hole 19a is slightly larger than the outer diameter of the supported portion 57d. The supported portion 57d is inserted into the through hole 19a and rotatably supported. That is, the through hole 19a functions as a sliding bearing for the rotating shaft 57.

[0090] The second end 57b is located on the opposite side of the first end 57a. The second end 57b is rotatably supported by the lower wall 12 of the housing 6. A recess 12b is provided on the upper surface of the lower wall 12, centered on the drive axis J5. That is, the housing 6 has a recess 12b. The recess 12b is circular in plan view, centered on the drive axis J5. The second end 57b is inserted into the recess 12b.

[0091] The second end portion 57b has a fourth surface 57k facing axially to one side (downward). The fourth surface 57k is the lower end surface of the rotating shaft 57. The fourth surface 57k faces the bottom surface 12c of the recess 12b. The fourth surface 57k and the bottom surface 12c may be in contact with each other. The inner diameter of the recess 12b is slightly larger than the outer diameter of the second end portion 57b. The second end portion 57b is rotatably supported in the recess 12b. That is, the recess 12b functions as a sliding bearing for the rotating shaft 57.

[0092] In this embodiment, the rotating shaft 57 is rotatably supported by an upper wall 11 and a lower wall 12 that face each other in the axial direction of the drive axis J5. According to this embodiment, the support of the rotating shaft 57 can be made more stable compared to cases such as when the rotating shaft 57 is cantilevered.

[0093] In this embodiment, the rotating shaft 57 is connected to the rotating part 58 of the actuator 59 by spline fitting. By employing spline fitting as the connection mechanism between the rotating shaft 57 and the rotating part 58, the ease of assembly between the parking mechanism 50 and the actuator 59 can be improved, but on the other hand, it allows axial movement of the rotating shaft 57 relative to the rotating part 58. As a result, there is a risk that the rotating shaft 57 may detach from the bearing portion (recess 12b in this embodiment). For this reason, in conventional structures, separate components such as E-rings and pins were used to suppress the detachment of the rotating shaft 57.

[0094] According to this embodiment, the first surface 58b of the actuator 59 and the second surface 57t of the rotating shaft 57 face each other in the axial direction of the drive axis J5. The first surface 58b contacts the second surface 57t, restricting the upward movement of the rotating shaft 57. According to this embodiment, the upward movement of the rotating shaft 57 can be restricted without using separate members such as retaining rings and pins, thereby reducing the number of parts and providing a drive device 1 that is easy to assemble.

[0095] According to this embodiment, the first surface 58b is provided on the rotating part 58 of the actuator 59. Therefore, even when the first surface 58b and the second surface 57t are in contact with each other, no dynamic frictional force resistance is generated between the first surface 58b and the second surface 57t. According to this embodiment, the detachment of the rotating shaft 57 can be suppressed without reducing the power transmission efficiency from the actuator 59 to the rotating shaft 57.

[0096] In this embodiment, the distance h1 between the first surface 58b and the second surface 57t in the axial direction of the drive axis J5 is smaller than the insertion depth h2 of the second end 57b into the recess 12b. Therefore, even when the rotating shaft 57 moves upward (to the other axial direction of the drive axis J5), which is the direction in which it moves away from the recess 12b, the first surface 58b and the second surface 57t remain in contact. The first surface 58b and the second surface 57t restrict the upward movement of the rotating shaft 57 and prevent the rotating shaft 57 from moving away from the recess 12b.

[0097] The distance dimension h1 and insertion depth h2 change as the rotating shaft 57 moves axially along the drive axis J5 relative to the housing 6. The distance dimension h1 and insertion depth h2 are correlated with each other. As the rotating shaft 57 moves upward, the distance dimension h1 decreases, and consequently, the insertion depth h2 decreases by the same amount. Therefore, if the rotating shaft 57 satisfies the above relationship at any position, it will satisfy the above relationship at any other position.

[0098] Furthermore, according to this embodiment, the distance dimension j between the end face 57aa (i.e., the upper end face) of the first end portion 57a ​​and the bottom surface 58ca of the rotating portion 58 is sufficiently larger than the distance dimension h1 between the first surface 58b and the second surface 57t. Therefore, it is possible to prevent the end face 57aa and the bottom surface 58ca from coming into contact before the first surface 58b and the second surface 57t come into contact. As a result, the first surface 58b and the second surface 57t can be reliably made to function as surfaces that restrict the movement of the rotating shaft 57.

[0099] In this embodiment, the first surface 58b is provided on the end face of the cylindrical portion 58a facing one axial side (downward) of the drive axis J5. Since the end face of the cylindrical portion 58a is relatively easy to process, it is easy to improve surface accuracy. According to this embodiment, a rotating portion 58 having a highly accurate first surface 58b can be formed, and the distance dimension h1 with respect to the second surface 57t can be easily controlled.

[0100] Furthermore, by providing the first surface 58b on the end face of the cylindrical portion 58a, the first surface 58b can be made to form an annular shape centered on the drive axis J5. This allows the first surface 58b and the second surface 57t to be in stable contact around the drive axis J5.

[0101] In this embodiment, the second surface 57t is a surface that connects the large-diameter portion 57c and the first end portion 57a ​​in a stepped manner. According to this embodiment, the second surface 57t can be made annular with respect to the drive axis J5, and the first surface 58b and the second surface 57t can be stably brought into contact around the drive axis J5. In this embodiment, a recessed portion 57g is provided at the base of the spline projection 57m, and the incomplete spline shape at the base of the spline projection 57m is removed. Therefore, it is possible to insert the spline projection 57m into the spline groove 58f until the first surface 58b and the second surface 57t come into contact.

[0102] Note that the positions of the first surface 58b and the second surface 57t described in this embodiment are examples only. The locations of the first surface 58b and the second surface 57t are not limited as long as they are provided on the rotating part 58 and the rotating shaft 57, respectively. For example, the first surface may be provided on the bottom 58c of the rotating part 58, and the second surface may be provided on the end face of the first end 57a of the rotating shaft 57.

[0103] In this embodiment, the second end 57b of the rotating shaft 57 faces the bottom surface 12c of the recess 12b on the fourth surface 57k. The bottom surface 12c contacts the fourth surface 57k, restricting the downward movement of the rotating shaft 57 and preventing the spline projection 57m from disengaging from the spline groove 58f.

[0104] In this embodiment, the distance k1 between the fourth surface 57k and the bottom surface 12c in the axial direction of the drive axis J5 is smaller than the engagement length k2 between the spline projection 57m and the spline groove 58f. Therefore, even if the spline projection 57m moves downward (to one side in the axial direction of the drive axis J5), which is the direction in which it moves away from the spline groove 58f, the fourth surface 57k and the bottom surface 12c remain in contact. The fourth surface 57k and the bottom surface 12c restrict the downward movement of the rotating shaft 57 and prevent the spline projection 57m from moving away from the spline groove 58f.

[0105] Furthermore, the distance dimension k1 and the fitting length k2 have the same correlation as the relationship between the distance dimension h1 and the insertion depth h2 described above. Therefore, if the rotating shaft 57 satisfies the above relationship at any position, the distance dimension k1 and the fitting length k2 will satisfy the above relationship at any position.

[0106] The rotating shaft 57 in this embodiment is assembled from outside the housing 6. Hereinafter, a method for assembling the drive unit 1, specifically the step of assembling the rotating shaft 57 and the actuator 59 to the housing 6, will be described.This assembly method includes a shaft insertion step of inserting the rotating shaft 57 into the inside of the housing 6 and a connecting step of connecting the actuator 59 to the first end 57a of the rotating shaft 57.

[0107] In the shaft insertion process, the worker first inserts the rotating shaft 57 into the housing 6 through a through hole 19a provided in the upper wall 11. At this time, the worker inserts the rotating shaft 57 into the through hole 19a from the second end 57b side. The worker also inserts the second end 57b of the rotating shaft 57 into the recess 12b of the lower wall 12. In this way, the worker supports the rotating shaft 57 straddling the space between the upper wall 11 and the lower wall 12. After the shaft insertion process, the rotating shaft 57 protrudes from the housing 6 at its first end 57a.

[0108] In the coupling process, the worker connects the actuator 59 to the first end portion 57a ​​protruding from the housing 6. In the coupling process, the worker aligns the first surface 58b of the actuator 59 with the second surface 57t of the rotating shaft 57 in the axial direction of the drive axis J5. After the coupling process, the actuator 59 is fastened and secured to the outer surface of the housing 6 with bolts or the like.

[0109] According to the assembly method of this embodiment, the rotating shaft 57 can be prevented from falling out of the housing 6 simply by inserting the rotating shaft 57 into the through hole 19a and connecting the actuator 59. In other words, there is no need to attach a retaining clip to the rotating shaft 57, and the assembly process can be simplified. In the assembly method of this embodiment, it is preferable to fix the flange 55 to the outer surface of the rotating shaft 57 inside the first housing space 10a before inserting the rotating shaft 57 into the recess 12b during the shaft insertion step.

[0110] <flange> The flange 55 is provided on the outer circumferential surface of the rotating shaft 57. In this embodiment, the flange 55 is a separate component from the rotating shaft 57 and is fixed to the outer circumferential surface of the rotating shaft 57. However, the flange 55 may also be part of the rotating shaft 57.

[0111] The flange 55 is positioned between the upper wall 11 and the lower wall 12 of the first projection 10. As described above, it is rotatably supported on the upper wall 11 and the lower wall 12 of the rotating shaft 57. By fixing the flange 55 to the rotating shaft 57 between the upper wall 11 and the lower wall 12, the upper wall 11 and the lower wall 12 can support the flange 55 and the rotating shaft 57 at both ends. Therefore, the upper wall 11 and the lower wall 12 can stably support the rotating shaft 57 against the reaction force applied to the rotating shaft 57 from the flange 55.

[0112] The flange 55 extends radially along the drive axis J5. The flange 55 rotates around the drive axis J5 together with the rotating shaft 57. According to this embodiment, the rotating shaft 57 extends vertically within the first projection 10. The flange 55 also rotates along a plane perpendicular to the vertical direction between the upper wall 11 and the lower wall 12 of the first projection 10. According to the structure of this embodiment, the first housing space 10a inside the first projection 10 can be effectively utilized to efficiently arrange each part of the transmission unit 50A.

[0113] As shown in Figure 6, the flange 55 of this embodiment has a flange body 55a extending radially along the drive axis J5, and a protruding piece 55b provided at the tip of the flange body 55a. The protruding piece 55b protrudes from the flange body 55a along the axial direction of the drive axis J5.

[0114] The flange body 55a is plate-shaped and perpendicular to the drive axis J5. The flange body 55a is provided with a connecting hole 55h that penetrates in the thickness direction. The connecting portion 54a of the cam rod 54 passes through the connecting hole 55h. The connecting portion 54a of the cam rod 54 is rotatable about the connecting hole 55h.

[0115] <Camrod> The cam rod 54 has a connecting portion 54a, an intermediate portion 54b, and a rod body 54c. In the cam rod 54, a first bent portion 54P is provided between the connecting portion 54a and the intermediate portion 54b, and a second bent portion 54Q is provided between the intermediate portion 54b and the rod body 54c. The cam rod 54 is bent at approximately 90° at the first bent portion 54P and the second bent portion 54Q. The cam rod 54 is a rod shape with a circular cross-section after being bent at the first bent portion 54P and the second bent portion 54Q.

[0116] The connecting portion 54a extends along the axial direction of the drive axis J5. Therefore, the connecting portion 54a extends parallel to the rotating shaft 57. The connecting portion 54a is inserted into the connecting hole 55h of the flange 55. This rotatably connects and supports the connecting portion 54a with respect to the flange 55. In other words, the cam rod 54 is rotatably supported by the flange 55 at the connecting portion 54a. A projection 54ac is provided on the outer circumference of the connecting portion 54a to prevent the connecting portion 54a from detaching from the connecting hole 55h.

[0117] The rod body 54c extends along the axial direction of the central axis J1. The rod body 54c extends in a direction perpendicular to the connecting portion 54a. The rod body 54c passes inside the sleeve 56. The rod body 54c is guided by the sleeve 56. The cam rod 54 also moves along the axial direction of the central axis J1 in conjunction with the movement of the flange 55 (i.e., rotation around the drive axis J5).

[0118] The intermediate section 54b connects the connecting section 54a and the rod body 54c. The intermediate section 54b is perpendicular to both the connecting section 54a and the rod body 54c. The intermediate section 54b also extends in a direction perpendicular to the drive axis J5 and the central axis J1. One end of the intermediate section 54b is connected to the connecting section 54a, and the other end is connected to the rod body 54c.

[0119] The intermediate section 54b extends along the radial direction of the central axis J1. The intermediate section 54b is provided to shift the relative position of the connecting section 54a and the rod body 54c. By arranging the intermediate section 54b to extend along the radial direction of the central axis J1, the connecting section 54a can be positioned closer to the central axis J1 relative to the rod body 54c. This allows the cam 53 supported by the rod body 54c to be positioned in the optimal location, while the flange 55 connected to the connecting section 54a, the rotating shaft 57, and the actuator 59 can be positioned closer to the central axis J1. As a result, the various parts of the parking mechanism 50 can be densely arranged around the central axis J1, reducing the space required for the parking mechanism 50 within the drive unit 1.

[0120] A protruding piece 55b of the flange 55 is positioned on one axial side (+Y side) of the intermediate section 54b. The protruding piece 55b is positioned on the parking gear 51 side relative to the intermediate section 54b in the axial direction of the central axis J1, and overlaps the intermediate section 54b when viewed from the axial direction of the central axis J1. The protruding piece 55b has an opposing surface 55c that faces the intermediate section 54b. The opposing surface 55c faces the intermediate section 54b with a gap in the axial direction of the central axis J1.

[0121] The coil spring 50d, cam 53, and cap 50c are passed through the rod body 54c. In other words, the coil spring 50d, cam 53, and cap 50c are attached to the rod body 54c. In the following description, the end of the rod body 54c that is connected to the intermediate section 54b will be referred to as the base end 54cb, and the end opposite the base end 54cb will be referred to as the tip end 54ca.

[0122] The coil spring 50d is positioned on the base end 54cb side of the rod body 54c relative to the cam 53. A projection 54cc, larger than the inner diameter of the coil spring 50d, is provided on the outer circumference of the base end 54cb of the rod body 54c. The coil spring 50d is positioned between the projection 54cc and the cam 53 in a compressed state relative to its natural length. The coil spring 50d applies a force to the cam 53 toward the tip 54ca side of the rod body 54c.

[0123] Figure 7 is a cross-sectional view of the drive device 1 near the tip 54ca of the rod body 54c. The cap 50c is fixed to the tip 54ca of the rod body 54c. The cap 50c is positioned on the rod body 54c on the tip 54ca side of the cam 53. The cap 50c contacts the end face of the cam 53. The cap 50c restricts the cam 53 from moving toward the tip 54ca side relative to the rod body 54c. The cap 50c prevents the cam 53 from falling off the tip 54ca of the rod body 54c.

[0124] <Cam> The cam 53 is annular in shape with the rod body 54c at its center. The rod body 54c is inserted through a through hole in the center of the cam 53. The inner diameter of the through hole in the cam 53 is larger than the outer diameter of the rod body 54c. The cam 53 is sandwiched between the coil spring 50d and the cap 50c in the longitudinal direction of the rod body 54c. The coil spring 50d is compressed as the cam 53 moves toward the base end 54cb. When the cam 53 receives a force toward the base end 54cb that is stronger than the repulsive force of the coil spring 50d, it compresses the coil spring 50d and moves toward the base end 54cb relative to the rod body 54c.

[0125] The cam 53 contacts the cam contact portion 52c of the parking pole 52 on its outer circumferential surface. The cam has a first portion 53a and a second portion 53b. The first portion 53a and the second portion 53b are arranged coaxially. The second portion 53b is located on the tip 54ca side relative to the first portion 53a. The first portion 53a and the second portion 53b are each frustoconical in shape. The outer circumferential surfaces of the first portion 53a and the second portion 53b are conical tapered surfaces, each with an outer diameter that gradually decreases from the base end 54cb side to the tip 54ca side of the rod body 54c. Therefore, the cross-sections of the first portion 53a and the second portion 53b are each circular. The taper angle of the outer circumferential surface of the first portion 53a is sufficiently small compared to the taper angle of the outer circumferential surface of the second portion 53b. The taper angle of the outer surface of the second part 53b is set to be a sufficient angle to allow the cam 53 to smoothly disengage from the sleeve 56 and the cam contact portion 52c when transitioning from the locked state to the unlocked state. Note that the first part 53a may be cylindrical rather than frustoconical.

[0126] The movement of the rod body 54c is transmitted to the cam 53 via the coil spring 50d. As a result, the cam 53 moves along the length of the rod body 54c together with the rod body 54c. The cam 53 also contacts the cam contact portion 52c of the parking pawl 52 on its outer circumferential surface. The cam 53 moves in conjunction with the movement of the cam rod 54, thereby operating the parking pawl 52. In the unlocked state of the parking mechanism 50, the second portion 53b of the cam 53 faces the cam contact portion 52c of the parking pawl 52 with a gap in between. In the locked and standby states of the parking mechanism 50, the cam 53 contacts the cam contact portion 52c with its first portion 53a. When the state of the parking mechanism 50 switches between the locked and unlocked states, the cam 53 contacts the cam contact portion 52c with its second portion 53b and slides further. As a result, the cam 53 moves the cam contact portion 52c upward, causing the parking pawl 52 to rotate around the support axis J4. In the standby state, the protrusion 52a is pressed against the outer circumferential surface of the teeth 51a of the parking gear 51. In the standby state, even if the cam rod 54 moves to the locked position, the cam 53 cannot move and remains pressed against the cam contact portion 52c. As a result, the coil spring 50d is compressed between the cam 53 and the projection 54cc of the rod body 54c. The coil spring 50d presses the cam 53 against the cam contact portion 52c until the parking gear 51 rotates and the protrusion 52a engages with the teeth 51a.

[0127] <Sleeve> The sleeve 56 is cylindrical and extends along the sleeve axis J6. The tip 54ca of the rod body 54c is inserted into the sleeve 56. The sleeve 56 also supports the cam 53 from the opposite side of the parking pole 52 when locked. The cam 53 separates from the sleeve 56 when unlocked. The sleeve 56 guides the cam 53 and limits the operating range of the cam 53 and the cam rod 54. The sleeve 56 is provided with a sleeve notch 56e that opens radially outward on a portion of its inner surface. The sleeve 56 is fixed to the inner surface of the housing 6. The method of fixing the sleeve 56 will be described in detail later.

[0128] <Protruding piece> According to this embodiment, the flange 55 is provided with a protruding piece 55b. The protruding piece 55b is used in the process of assembling the parking mechanism 50 to the housing 6. After assembling the transmission section 50A of the parking mechanism 50 to the housing 6, the cam rod 54 is inserted into the sleeve 56 and the sleeve 56 is held in place by the housing 6. The process of inserting the cam rod 54 into the sleeve 56 and attaching the sleeve 56 to the housing 6 (hereinafter referred to as the sleeve attachment process) may be performed with the housing 6 tilted. In this embodiment, the sleeve attachment process is performed with the housing 6 tilted so that the side indicated by the Y-axis arrow in the figure is the downward side in the vertical direction. In the sleeve attachment process, the protruding piece 55b of the flange 55 is positioned below the intermediate section 54b of the cam rod 54. In the sleeve attachment process, the worker uses the protruding piece 55b to support the intermediate section 54b from below and inserts the tip 54ca of the rod body 54c into the sleeve 56. Furthermore, the worker secures the sleeve 56 to the inner surface of the housing 6. According to this embodiment, the cam rod 54, which tends to become unstable during the assembly process, can be temporarily held in place by the protruding piece 55b. This makes it easier to insert the tip 54ca of the rod body 54c into the sleeve 56, thereby simplifying the assembly process of the parking mechanism 50.

[0129] <Parking Gear> As shown in Figure 2, the parking gear 51 is provided on the outer circumferential surface of the second shaft 44. The parking gear 51 is positioned in the axial direction between the first gear 41 and the partition wall 66.

[0130] According to this embodiment, the parking gear 51 is positioned axially between the motor 2 and the first gear 41. That is, the parking gear 51 is positioned on the partition wall 66 side relative to the first gear 41. This allows the parking mechanism 50 to be positioned closer to the motor 2 side within the gear housing 82, and prevents the parking mechanism 50 from protruding significantly from the gear housing 82 in one axial direction (+Y side). As a result, the axial dimensions of the drive unit 1 can be reduced.

[0131] According to this embodiment, the parking gear 51 overlaps with at least a portion of the third gear 46g when viewed from a direction perpendicular to the axial direction. In other words, the axial position of the parking gear 51 overlaps with the axial position of the third gear 46g. According to this embodiment, the parking mechanism 50 and the power transmission unit 4 can be arranged overlapping in the axial direction. That is, the parking mechanism 50 can be placed in the gap of the power transmission unit 4, and the internal space of the gear housing 82 can be effectively utilized to reduce the size of the drive unit 1.

[0132] In this embodiment, the third gear 46g meshes with the small-diameter gear 43. Furthermore, the tooth width of the third gear 46g and the tooth width of the small-diameter gear 43 are approximately equal. Therefore, when viewed from a direction perpendicular to the axial direction, the parking gear 51 overlaps not only with the third gear 46g but also with at least a portion of the small-diameter gear 43.

[0133] As described above, the parking gear 51 is positioned closer to the motor 2 side relative to the first gear 41 in the axial direction. For this reason, the small-diameter gear 43 and the third gear 46g, which overlap with the parking gear 51 when viewed from a direction perpendicular to the axial direction, are also positioned closer to the motor 2 in the axial direction. The gear with the largest diameter in the power transmission unit 4 is the third gear 46g. By positioning the third gear 46g closer to the motor 2, the area of ​​the power transmission unit 4's housing space that overlaps with the third gear 46g when viewed from the axial direction can be made smaller in the axial direction, thereby enabling miniaturization of the drive unit 1.

[0134] As shown in Figure 3, according to this embodiment, the parking gear 51 overlaps with the large-diameter gear 42 in at least a portion when viewed from the axial direction. This allows a portion of the parking mechanism 50 and a portion of the power transmission unit 4 to be arranged overlapping in the axial direction. According to this embodiment, the diameter of the parking gear 51 can be increased to ensure sufficient braking force for the rotation of the power transmission unit 4 by the parking mechanism 50, while reducing the axial projected area of ​​the drive unit 1.

[0135] In this embodiment, the parking gear 51 is provided on the outer circumferential surface of the second shaft 44. The second shaft 44 is the shaft with the smallest transmitted torque among the multiple shafts of the power transmission unit 4. By providing the parking gear 51 on the second shaft 44, the reaction force applied to the parking mechanism 50 when locked can be reduced. According to this embodiment, the reaction force applied to the parking mechanism 50 can be reduced, thereby enabling miniaturization of the parking mechanism 50.

[0136] As shown in Figure 6, the parking gear 51 of this embodiment is annular in shape with respect to the central axis J1. The parking gear 51 rotates together with the second shaft 44. That is, the parking gear 51 rotates together with the first gear 41 around the central axis J1 in conjunction with the vehicle's wheels. Multiple teeth 51a are provided on the outer circumference of the parking gear 51, arranged along the circumferential direction. The teeth 51a protrude radially outward from the central axis J1. In the locked state, which will be described later, the teeth 51a mesh with the protrusions 52a.

[0137] <Pole Shaft> The pole shaft 50t extends along a support axis J4 parallel to the central axis J1. That is, the pole shaft 50t is a shaft parallel to the second shaft 44. The pole shaft 50t rotatably supports the parking pole 52.

[0138] In this embodiment, the pole shaft 50t is perpendicular to the rotating shaft 57. According to this embodiment, compared to the case where the rotating shaft 57 and the pole shaft 50t extend parallel to each other, it becomes possible to arrange the shafts three-dimensionally, and the overall size of the parking mechanism 50 can be reduced.

[0139] A coil spring 50s is attached to the pole shaft 50t. The coil spring 50s has a coil-shaped spring body 50sc and first legs 50sa and second legs 50sb extending from both ends of the spring body 50sc.

[0140] As shown in Figure 3, the pole shaft 50t is inserted into the spring body 50sc. The first leg portion 50sa contacts the outer surface of the catch tank 84. On the other hand, the second leg portion 50sb is hooked onto the spring attachment hole 52h provided in the parking pole 52, as shown in Figure 6. The coiled spring 50s applies an elastic force to the parking pole 52 in a direction that retracts its tip toward the sleeve 56.

[0141] According to this embodiment, a portion of the catch tank 84 is positioned directly below the pole shaft 50t and contacts the first leg portion 50sa of the coil spring 50s on its outer surface. As a result, the catch tank 84 supports the first leg portion 50sa and is connected to the parking pole 52 by the coil spring 50s. one An elastic force can be applied in a direction. Furthermore, compared to the case where a separate part is provided on the housing 6 to support the first leg portion 50sa, the cost required for processing the housing 6 can be reduced by utilizing the outer surface of the catch tank 84.

[0142] The position on the outer surface of the catch tank 84 where the first leg portion 50sa of the coil spring 50s is attached is just one example. The first leg portion 50sa may be attached to any position on the outer surface of the catch tank 84, for example, above the pole shaft 50t.

[0143] <Parking pole> As shown in Figure 6, the parking pawl 52 is positioned on the side of the parking gear 51. The parking pawl 52 has a base end portion 52d, a parking pawl body portion 52b extending diagonally downward from the base end portion 52d, a cam contact portion 52c, and a protrusion portion 52a.

[0144] The parking pole body 52b is positioned between the parking gear 51 and the sleeve 56 when viewed from the axial direction of the central axis J1. The protrusion 52a is provided on the surface of the parking pole body 52b facing the parking gear 51. On the other hand, the cam contact portion 52c is provided on the surface of the parking pole body 52b facing the sleeve 56. The cam contact portion 52c is located at the tip of the parking pole 52. The protrusion 52a is located between the base end portion 52d and the cam contact portion 52c in the longitudinal direction of the parking pole 52.

[0145] A support hole 52k is provided at the base end 52d of the parking pole 52, centered on the support axis J4. A pole shaft 50t is inserted into the support hole 52k. As a result, the parking pole 52 is supported by the pole shaft 50t at the base end 52d and can rotate around the support axis J4 by the pole shaft 50t.

[0146] The protrusion 52a extends from the parking pawl body 52b toward the parking gear 51. The protrusion 52a faces the teeth 51a of the parking gear 51. As the parking pawl 52 rotates around the pawl shaft 50t, the protrusion 52a moves toward and away from the parking gear 51.

[0147] The parking pole 52 can be in one of three states: locked, unlocked, or standby. The locked and unlocked states can be transitioned between in response to the operator's actions. The standby state appears when the operator transitions from the unlocked state to the locked state, during the transition process.

[0148] The locked state is a state in which the protrusion 52a engages with the parking gear 51, thereby inhibiting the rotation of the parking gear 51. In the locked state of the parking mechanism 50, the protrusion 52a fits between the teeth 51a of the parking gear 51.

[0149] The unlocked state is a state in which the protrusion 52a is separated from the parking gear 51, releasing the lock and allowing the parking gear 51 to rotate. In the unlocked state of the parking mechanism 50, the protrusion 52a retracts radially outward from between the teeth 51a and the central axis J1.

[0150] The standby state is a state in which the protrusion 52a is pressed against the outer circumferential surface of the teeth 51a of the parking gear 51, waiting to enter the locked state. In the standby state, when the parking gear 51 rotates and the gap in the teeth 51a aligns with the protrusion 52a, the protrusion 52a engages with the teeth 51a and transitions to the locked state.

[0151] The cam contact portion 52c is located inside the sleeve notch 56e (see Figure 7). The parking pawl 52 receives force from the cam 53 at the cam contact portion 52c and rotates around the support axis J4. In other words, the parking pawl 52 operates in conjunction with the movement of the cam 53.

[0152] As shown in Figure 3, the parking pawl 52 in this embodiment is positioned above the parking gear 51. Therefore, compared to the case where the parking pawl 52 is positioned horizontally relative to the parking gear 51, the horizontal enlargement of the gear housing 82 can be suppressed. Furthermore, according to this embodiment, the vertical positions of the parking pawl 52 and the parking gear 51 coincide with the vertical position of the third gear 46g. Therefore, the parking pawl 52 and the parking gear 51 can be suppressed from protruding significantly in the vertical direction relative to the upper and lower ends of the third gear 46g. As a result, the vertical enlargement of the gear housing 82 can be suppressed.

[0153] According to this embodiment, the third gear 46g, the catch tank 84, and the transmission unit 50A of the parking mechanism 50 are arranged side by side along the horizontal direction. Therefore, it is possible to suppress the catch tank 84 and the transmission unit 50A from protruding significantly in the vertical direction relative to the upper and lower ends of the third gear 46g, and the drive unit 1 can be made smaller in the vertical direction.

[0154] According to this embodiment, the first protrusion 10 of the housing 6 is located above the parking gear 51. According to this embodiment, the first protrusion 10 can accommodate a part of the parking mechanism 50 which is located above the parking gear 51, and the area above the parking gear 51 can be efficiently utilized to make the drive unit 1 smaller in the vertical direction.

[0155] According to this embodiment, the parking pole 52 is positioned on one axial side (+Y side) relative to the transmission unit 50A, and overlaps with the first projection 10 when viewed from the axial direction. According to this embodiment, by arranging the parking pole 52 and the transmission unit 50A side by side in the axial direction, it is possible to suppress the increase in size of the parking mechanism 50 in the vertical direction (Z-axis direction) and the vehicle longitudinal direction (X-axis direction). This makes it possible to reduce the projected area of ​​the drive unit 1 when viewed from the axial direction.

[0156] According to this embodiment, the catch tank 84 is located above the second gear section 48, and the vertical position of the parking pawl 52 coincides with the vertical position of the catch tank 84. Therefore, the parking pawl 52, which is part of the parking mechanism 50, can be arranged horizontally alongside the catch tank 84. According to this embodiment, it is possible to suppress the catch tank 84 or the parking mechanism 50 from protruding upward relative to other members in the gear housing section 82, and the drive unit 1 can be made smaller in the vertical direction.

[0157] In this embodiment, the catch tank 84 is located above the second gear section 48, and the transmission section 50A is located above the first gear 41. Therefore, compared to the case where the transmission section 50A is arranged horizontally relative to the first gear 41, the horizontal enlargement of the gear housing section 82 can be suppressed. In this embodiment, the space above the relatively small diameter first gear 41 can be effectively utilized to miniaturize the drive unit 1.

[0158] <Sleeve support> Next, we will explain in detail how sleeve 56 is supported. Figure 8 is an exploded perspective view showing the sleeve 56 and a portion of the housing 6 that holds the sleeve 56. The sleeve 56 has an annular portion 56a, an arc portion 56b, and an anti-rotation portion 56c. The annular portion 56a is circular with the sleeve axis J6 as its center. The annular portion 56a surrounds the tip 54ca of the cam rod 54 from the radially outer side of the sleeve axis J6.

[0159] As shown in Figure 8, the arc portion 56b is connected to the other axial side (-Y side) of the annular portion 56a. The arc portion 56b extends in an arc shape centered on the sleeve axis J6. The axial length of the arc portion 56b is greater than the axial length of the annular portion 56a. A sleeve notch 56e is provided in the region enclosed by the circumferential end faces of the arc portion 56b with respect to the sleeve axis J6 and the end face on one axial side of the annular portion 56a. The cam rod 54, which is positioned inside the sleeve 56, is exposed radially outward from the sleeve axis J6 at the sleeve notch 56e and contacts the parking pole 52.

[0160] The anti-rotation portion 56c protrudes radially outward from the sleeve axis J6 relative to the annular portion 56a. The anti-rotation portion 56c is positioned in the region where the arc portion 56b is provided in the circumferential direction around the sleeve axis J6.

[0161] In this embodiment, the outer diameter of the arc portion 56b is larger than the outer diameter of the annular portion 56a. By making the outer diameter of the arc portion 56b larger than the outer diameter of the annular portion 56a, the arc portion 56b can be tightly pressed against the holding surface of the housing 6 when it is held by the housing 6. This can improve the stability of the housing 6's holding of the sleeve 56. Circular section 56a A rotation-preventing portion 56c is provided on the outer circumferential surface. The closer the outer diameter of the annular portion 56a is to the inner diameter of the insertion portion (retaining recess 85) of the housing 6, the more difficult it becomes to attach the annular portion 56a to the housing 6. According to this embodiment, by making the outer diameter of the annular portion 56a smaller than the outer diameter of the arc portion 56b, the positioning of the rotation-preventing portion 56c and the attachment process to the housing 6 can be made easier.

[0162] In this embodiment, the axial dimension of the arc portion 56b is greater than the axial dimension of the first portion 53a of the cam 53. If the axial dimension of the arc portion 56b is too short, there is a risk that the arc portion 56b may not be able to stably support the first portion 53a when subjected to a load from the cam 53. According to this embodiment, the arc portion 56b 53a of the first part of cam 53 By making it larger in the axial direction, the first portion 53a of the cam 53 can be stably supported by the arc portion 56b even when a load is applied from the cam 53.

[0163] The partition wall portion 66 of the housing body 6B is provided with a retaining recess 85 for holding the sleeve 56, and a sleeve guide portion 87a and an extended wall portion 87e of the first wall portion 87 that protrude from the inner edge of the retaining recess 85 toward the other axial side (-Y side).

[0164] The retaining recess 85 opens on the other axial side (-Y side) of the central axis J1. That is, the retaining recess 85 opens towards the gear cover 6C side. The retaining recess 85 holds the arc portion 56b of the sleeve 56.

[0165] The sleeve guide portion 87a and the extension wall portion 87e of the first wall portion 87 extend in an arc shape with respect to the sleeve axis J6. In the circumferential direction of the sleeve axis J6, the region where the sleeve guide portion 87a and the extension wall portion 87e are provided coincides with the region where the arc portion 56b of the sleeve 56 is provided.

[0166] As shown in Figure 7, the sleeve 56 has a tip surface 56t facing the other axial side (-Y side). The tip surface 56t is covered from the other axial side (-Y side) by the second wall portion 88 of the gear cover 6C. That is, the gear cover 6C is provided with a second wall portion (retaining wall portion) 88 that covers the surface of the sleeve 56 facing the other axial side (-Y side) (tip surface 56t).

[0167] In this embodiment, the sleeve 56 is inserted into a retaining recess 85 provided in the housing body 6B, which opens on one axial side (+Y side). The tip surface 56t of the sleeve 56 is covered from the other axial side (-Y side) by the second wall portion 88 of the gear cover 6C. This prevents the sleeve 56 from detaching from the retaining recess 85. In this embodiment, the sleeve 56 is fixed to the housing 6 by two components that make up the housing 6 (housing body 6B and gear cover 6C). According to this embodiment, the number of parts can be reduced compared to the case where a separate fixing component is provided on the housing 6. Furthermore, the worker performing the assembly inserts the sleeve 56 into the retaining recess 85 and combines the housing body 6B and the gear cover 6C to complete the fixing of the sleeve 56, thus simplifying the assembly process compared to the case where the sleeve 56 is fixed with fasteners such as screws.

[0168] According to this embodiment, the second wall portion 88 covering the tip surface 56t of the sleeve 56 is part of the first partition wall portion 89 that partitions the breather chamber R8 inside the gear housing portion 82. That is, the second wall portion 88 has the function of being part of the first partition wall portion 89 and the function of being a retaining wall portion. According to this embodiment, the various spaces arranged inside the gear housing portion 82 can be densely arranged, and the gear housing portion 82 can be made smaller. In addition, by giving the second wall portion 88 multiple functions, the processing cost of the housing 6 can be reduced compared to the case in which separate wall portions for each function are provided.

[0169] In this embodiment, the second wall portion 88 covers at least a portion of the tip surface 56t of the sleeve 56. Furthermore, the first wall portion 87, which together with the second wall portion 88 constitutes the first compartment wall portion 89, surrounds at least a portion of the sleeve 56. That is, the sleeve 56 is surrounded and supported by the first wall portion 87 and the second wall portion 88, which constitute the first compartment wall portion 89. This allows the housing 6 to stably support the sleeve 56.

[0170] In this embodiment, the tip surface 56t of the sleeve 56 is positioned to one axial side (+Y side) of the first mating surface 87f of the first wall portion 87, which faces the other axial side (-Y side). The first mating surface 87f of the first wall portion 87 faces the second mating surface 88f of the second wall portion 88, which faces the other axial side (+Y side), in the axial direction. The first mating surface 87f and the second mating surface 88f are in contact with each other. When the tip surface 56t of the sleeve 56 is positioned to one axial side (-Y side) of the first mating surface 87f, there is a risk that excessive load will be applied to the sleeve 56 when the housing body 6B and the gear cover 6C are fastened together. According to this embodiment, the axial size of the sleeve 56 can be set to a height that does not protrude axially from the first wall portion 87, thereby suppressing the application of excessive load to the sleeve 56.

[0171] A notch 87t is provided in the sleeve guide portion 87a of the first wall portion 87. The notch 87t opens axially toward the gear cover 6C. The opening of the notch 87t is covered by the second wall portion 88. The notch 87t extends with a uniform width along the axial direction of the sleeve axis J6. The width dimension of the notch 87t is slightly larger than the width dimension of the anti-rotation portion 56c. The anti-rotation portion 56c of the sleeve 56 is inserted into the notch 87t. As shown in Figure 7, the notch 87t reaches the retaining recess 85.

[0172] According to this embodiment, the anti-rotation portion 56c of the sleeve 56 is inserted into the notch 87t that opens on the gear cover 6C side, thereby preventing the sleeve 56 in the holding recess 85 from rotating around the sleeve axis J6. This allows the sleeve 56 to be positioned in the circumferential direction around the sleeve axis J6. This stabilizes the opening direction of the sleeve notch 56e provided in the sleeve 56, and ensures that the cam 53 is reliably exposed to the parking pole 52.

[0173] In this embodiment, the anti-rotation portion 56c is provided on the outer circumferential surface of the annular portion 56a, but the configuration of the anti-rotation portion 56c is not limited to this embodiment. The anti-rotation portion 56c only needs to protrude radially outward from the annular portion 56a, and may, for example, be provided on the outer circumferential surface of the arc portion 56b. Furthermore, the radially outward end of the anti-rotation portion 56c only needs to be located radially outward from the outer circumferential surface of the annular portion 56a.

[0174] As shown in Figure 7, a second projection (protrusion) 82g is provided on the surface of the housing body 6B facing one axial side (+Y side), projecting in the axial direction. In this embodiment, the second projection 82g is provided on the surface of the partition wall 66 facing one axial side. The second projection 82g is circular when viewed from the axial direction. The second projection 82g also overlaps with the retaining recess 85 when viewed from the axial direction. A second accommodating space (accommodating space) 82h is provided inside the second projection 82g. The second accommodating space 82h is a recess provided on the surface of the partition wall 66 facing the other axial side (-Y side). The second projection 82g is provided at the bottom of the retaining recess 85. The second projection 82g can accommodate the tip 54ca of the cam rod 54.

[0175] According to this embodiment, the partition wall portion 66 of the housing body 6B protrudes to one side in the axial direction to accommodate the tip 54ca of the cam rod 54. This allows the parking mechanism 50 to be positioned closer to the motor 2 inside the housing 6 while ensuring the operating stroke of the cam rod 54. As a result, the entire drive unit 1 can be made smaller in the axial direction. Furthermore, by partially protruding only a part of the partition wall portion 66 to one side in the axial direction (+Y side) in order to ensure the stroke of the cam rod 54, the external dimensions of the housing 6 can be made smaller compared to the case where the entire partition wall portion 66 is positioned to one side in the axial direction.

[0176] As shown in Figure 3, in this embodiment, the sleeve 56 is positioned forward of the vehicle (+X side, one side in the horizontal direction) of the differential axis J3, intermediate axis J2, and central axis J1. The sleeve 56 is also positioned above the differential axis J3, intermediate axis J2, and central axis J1. The fluid O inside the gear housing 82 is mainly scooped up by the third gear 46g rotating around the differential axis J3, and auxiliaryly scooped up by the second gear section 48 rotating around the intermediate axis J2. According to this embodiment, by arranging the sleeve 56 as described above, the sleeve 56 can be positioned as far away from the third gear 46g as possible, and similarly farther from the second gear section 48. Furthermore, since the sleeve 56 in this embodiment is supported by the first compartment wall section 89 surrounding the opening of the breather 8, it is located in the vicinity of the breather 8. As a result, the breather 8 can be separated from the third gear 46g and the second gear section 48, thereby suppressing the arrival of fluid O at the opening of the breather 8.

[0177] As described above, the sleeve 56 is located on the front side (+X side) and above side (+Z side) of the vehicle with respect to the differential axis J3, intermediate axis J2, and central axis J1. Therefore, no gears of the power transmission unit 4 are located directly below the sleeve 56. According to this embodiment, the area 82ma directly below the sleeve 56 at the bottom 82m is located above the differential axis J3, intermediate axis J2, and central axis J1. Therefore, it is possible to prevent the provision of an empty space inside the gear housing 82 directly below the sleeve 56, thereby miniaturizing the drive unit 1. In addition, by partially positioning the bottom 82m of the gear housing 82 upward, it becomes easier to raise the fluid level O inside the gear housing 82, and the fluid O can be efficiently scooped up by each gear of the power transmission unit 4. Furthermore, some of the fluid O that is scattered by the scooping up of the fluid O by each gear reaches the sleeve 56, lubricates the sleeve 56, and reduces the sliding resistance with the cam 53. Furthermore, since the opening of the breather 8 is located within the space partitioned by the first partition wall 89 and the second partition wall 86, it is difficult for scattered fluid O to reach it.

[0178] As shown by the dashed line (double-dotted line) in Figure 3, the housing 6 may be provided with a supply passage 6f extending from the catch tank 84 to the sleeve 56. The supply passage 6f is, for example, a through hole extending from the catch tank 84 to a retaining recess 85 that holds the sleeve 56. In addition, a part of the supply passage 6f may include a rib that protrudes from the partition wall 66 into the internal space of the gear housing 82. In this case, the fluid O flowing out from the catch tank 84 travels along the top of the rib and reaches the sleeve 56. The fluid O supplied to the sleeve 56 reduces the sliding resistance between the sleeve 56 and the cam 53.

[0179] Although various embodiments and modifications of the present invention have been described above, the configurations and combinations thereof in each embodiment and modification are merely examples, and additions, omissions, substitutions, and other changes to the configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited by its embodiments.

[0180] For example, in the above-described embodiment, a retaining recess for holding the sleeve is provided in the housing body, and a retaining wall portion covering the tip surface of the sleeve is provided in the gear cover. However, the retaining recess may be provided in the gear cover, and the retaining wall portion may be provided in the housing body. [Explanation of Symbols]

[0181] 1...Drive unit, 2...Motor, 4...Power transmission unit, 4b...Differential gear, 5...Parking device, 6...Housing, 6f...Supply path, 8...Breather, 10...First protrusion (protrusion), 10a...First storage space (storage space), 11...Upper wall (first wall), 12...Lower wall (second wall), 12b...Recess, 12c...Bottom surface, 19a...Through hole, 41...Gear, 41...First gear, 42...Large diameter gear, 43...Small diameter gear, 44...Second shaft (shaft T), 46g...3rd gear, 48...2nd gear section, 50...parking mechanism, 50s...coil spring, 50sa...1st leg section, 50sb...2nd leg section, 50t...pole shaft, 50A...transmission section, 51...parking gear, 52...parking pole, 52a...protrusion, 53...cam, 54...cam rod, 54a...connecting section, 54b...intermediate section, 54c...rod body, 54ca...tip, 55...flange, 55a...flange body, 5 5b...Protruding piece, 56...Sleeve, 56a...Ring ring portion, 56b...Arch portion, 56c...Anti-rotation portion, 57...Rotating shaft, 57a...First end, 57b...Second end, 57c...Large diameter portion, 57d...Supported portion, 57k...Fourth surface, 57m...Spline projection, 57t...Second surface, 58...Rotating portion, 58a...Cylindrical portion, 58b...First surface, 58f...Spline groove, 59...Actuator, 82...Gear housing portion, 82g...Second projection (protrusion) J1, k1…distance dimension, h2…insertion depth, J1…center axis, J2…intermediate axis, J3…differential axis, J5…drive axis, J6…sleeve axis, k2…fitting length

Claims

1. A motor that rotates around a central axis, A power transmission unit that transmits power from the motor, Parking mechanism and The system comprises a power transmission section and a housing having a gear housing section that accommodates the parking mechanism, The power transmission unit has at least one shaft, The aforementioned parking mechanism is A parking gear provided on the outer circumferential surface of the shaft, A parking pawl having a protrusion that engages with the aforementioned parking gear, A transmission unit that transmits power to the aforementioned parking pole, It has a cylindrical sleeve, The aforementioned transmission unit is A cam rod that drives along the axial direction of the aforementioned central axis, It has a cam attached to the cam rod that operates the parking pole, The cam is guided by the sleeve, The gear housing section includes: A breather that connects the inside and outside of the gear housing, A partition wall is provided inside the gear housing that divides the space through which the breather opens. The gear housing section is, First housing member and The first housing member is arranged on one axial side of the first housing member and connected to the first housing member, The second housing member is provided with a retaining recess that opens on one side in the axial direction and holds the sleeve, The first housing member is provided with a retaining wall portion that covers the surface of the sleeve facing the other axial direction, The aforementioned retaining wall portion is part of the partition wall portion. Drive unit.

2. The partition wall portion has a first wall portion which is part of the second housing member and a second wall portion which is part of the first housing member, At least a portion of the outer surface of the sleeve is surrounded by the first wall portion, At least a portion of the end face of the sleeve facing the other axial side is covered by the second wall. The drive device according to claim 1.

3. The aforementioned sleeve is A ring-shaped section centered on the sleeve axis, It has an anti-rotation portion that protrudes radially outward from the annular portion relative to the sleeve axis, The drive device according to claim 2, wherein the first wall portion is provided with a notch into which the anti-rotation portion is inserted.

4. The sleeve has an arc portion that is connected to the other axial side of the annular portion and extends in an arc shape centered on the sleeve axis, The outer diameter of the arc portion is larger than the outer diameter of the annular portion. The drive device according to claim 3.

5. The cam has a first portion and a second portion, each having a circular cross-section and arranged coaxially. The second portion is located on the tip side of the cam rod relative to the first portion, The outer diameter of the second portion is smaller than the outer diameter of the first portion. The axial dimension of the arc portion is larger than the axial dimension of the first portion. The drive device according to claim 4.

6. On the surface of the second housing member facing one side in the axial direction, a projection is provided that overlaps with the retaining recess when viewed from the axial direction and protrudes in the axial direction. The drive device according to any one of claims 1 to 5, wherein a housing space capable of accommodating the tip of the cam rod is provided inside the protruding portion.

7. The power transmission unit is The shaft rotates around the central axis, A first gear is provided on the outer circumferential surface of the shaft, A second gear section having a large-diameter gear that meshes with the first gear, and a small-diameter gear that has a smaller diameter than the large-diameter gear and rotates together with the large-diameter gear around an intermediate axis, A differential has a third gear that meshes with the small-diameter gear and rotates around the differential axis, A catch tank opening upwards is positioned inside the gear housing. The parking gear is provided on the outer circumferential surface of the shaft, The third gear, the catch tank, and the transmission unit are arranged side by side along the horizontal direction. A drive device according to any one of claims 1 to 6.

8. The catch tank is located above the second gear section, The transmission unit is located above the first gear, The drive device according to claim 7.

9. The housing is provided with a supply passage extending from the catch tank to the sleeve. The drive device according to claim 7 or 8.

10. The sleeve is positioned on one side in the horizontal direction relative to the differential axis, the intermediate axis, and the central axis. The sleeve is positioned above the differential axis, the intermediate axis, and the central axis. The drive device according to any one of claims 7 to 9.

11. The gear housing has a bottom that covers the internal space from below, The area directly below the sleeve at the bottom is located above the differential axis, the intermediate axis, and the central axis. The drive device according to claim 10.

12. A catch tank opening upwards is positioned inside the gear housing. The aforementioned parking mechanism is A pole shaft that rotatably supports the aforementioned parking pole, The pole shaft is fitted with a coil spring, The aforementioned coil spring is, The first leg portion that contacts the outer surface of the catch tank, A drive device according to any one of claims 1 to 11, comprising a second leg portion that is hung on the parking pole.

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