Parking mechanism and method for assembling a parking mechanism

Abstract

One embodiment of the parking mechanism of the present invention includes: an actuator having a manual shaft extending along and rotating about a first axis; a flange disposed on the outer periphery of the manual shaft and extending radially along the first axis; a cam rod having a connecting portion connected to the flange and a rod body extending along a second axis orthogonal to the first axis and moving along the second axis following the movement of the flange; a coil spring mounted on the rod body; a cam mounted on the rod body, having its movement of the rod body transmitted via the coil spring and moving along the second axis; a braking member having an engagement portion and actuating with the movement of the cam; and a parking gear having teeth meshing with the engagement portion. The self-holding torque of the actuator is greater than the torque imparted to the manual shaft when the coil spring is at maximum compression.

Description

Technical Field

[0001] This invention relates to a parking mechanism and a method for assembling the parking mechanism. Background Technology

[0002] A parking mechanism is installed in the drive unit of the vehicle. Patent document 1 discloses a parking locking device (equivalent to a parking mechanism), in which a control cam is actuated by a drive unit, causing the locking pawl to engage with the parking gear.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-143893 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In existing parking mechanisms, a leaf spring is used to determine the rotational position of the manual shaft (drive shaft) in order to prevent it from rotating due to the reaction force from the cam side. Therefore, existing parking mechanisms suffer from an increase in the number of components and a larger overall size.

[0008] In view of the above, one of the objectives of the present invention is to provide a parking mechanism that can be miniaturized.

[0009] Technical solutions adopted to solve technical problems

[0010] One embodiment of the parking mechanism of the present invention includes: an actuator having a manual shaft extending along and rotating about a first axis; a flange disposed on the outer periphery of the manual shaft and extending radially along the first axis; a cam rod having a connecting portion and a rod body, the connecting portion being connected to the flange, the rod body extending along a second axis orthogonal to the first axis and moving along the second axis following the movement of the flange; a helical spring mounted on the rod body; a cam mounted on the rod body, transmitting the movement of the rod body via the helical spring and moving along the second axis; a braking member having an engaging portion and actuating with the movement of the cam; and a parking gear having teeth engaging with the engaging portion. An imaginary perpendicular line is defined from the first axis toward the second axis when viewed axially along the first axis. The connecting portion moves about the first axis relative to the perpendicular line within a range of ±45°. The spring constant of the helical spring is set to k. Let Xb be the maximum compression of the helical spring within the movable range of the rod body. Let R be the distance between the first axis and the connecting portion when viewed axially from the first axis. Let θ be the angle between the perpendicular line and the connecting portion when viewed axially from the first axis. Let Ts be the self-holding torque of the actuator, and Equation 1 below holds.

[0011] [Mathematical Expression 1]

[0012] Ts>k·Xb·R·cosθ …(Equation 1)

[0013] Invention Effects

[0014] According to one aspect of the present invention, a parking mechanism capable of miniaturization can be provided. Attached Figure Description

[0015] Figure 1 This is a conceptual diagram illustrating one embodiment of a drive device.

[0016] Figure 2 This is a perspective view of a parking mechanism according to one embodiment.

[0017] Figure 3 This is a cross-sectional view along the length of the cam rod of the drive unit in one embodiment, showing the unlocked state.

[0018] Figure 4 This is a cross-sectional view along the length of the cam rod of the drive unit in one embodiment, showing the locked state.

[0019] Figure 5 This is a cross-sectional view along the length of the cam rod of the drive unit in one embodiment, showing the standby state.

[0020] Figure 6 This is a front view of a parking pawl and parking gear according to one embodiment, showing the standby state.

[0021] Figure 7 This is a side view of a portion of the parking mechanism of one embodiment, viewed from the axial direction of the first axis.

[0022] Figure 8 This is a side view illustrating the flange fixing process, cam rod connection process, and bushing installation process of the assembly method of the parking mechanism according to one embodiment.

[0023] Figure 9 This is a perspective view showing an example of a tool connection portion that can be used in one embodiment.

[0024] Figure 10 This is a perspective view showing an example of a tool connection portion that can be used in one embodiment.

[0025] (Symbol Explanation)

[0026] 1. Drive unit; 3. Gear section; 6. Housing; 6a. Collision member; 8. Parking mechanism; 10. Parking gear; 11. Tooth section; 11a. Outer peripheral surface; 20. Parking pawl (brake member); 25. Engaging part; 29. ​​Pawl shaft; 30. Cam rod; 30a. Connecting part; 30b. Relay part; 30c. Rod body; 35. Cam; 39. Coil spring; 70. Actuator; 71. Manual shaft; 72. Housing; 72w. Opening; 73. Worm gear; 74. Countershaft gear section; 74. a. Worm gear; 74b. Small diameter gear; 75. Output gear section; 79. Motor; 79a. Rotating shaft; 79c, 79d. Tool connection section; 80. Bushing; 90. Flange; 91. Flange body; 92. Protrusion; 92f. Opposing surface; 92g. Groove; J1. First axis; J2. Second axis; J4. Fourth axis; J7. Seventh axis (axis); J8. Eighth axis; k. Spring constant; P. Perpendicular line; R. Distance; Ts. Holding torque; Xb. Maximum compression; θ. Angle Detailed Implementation

[0027] In the following description, the vertical direction is defined based on the positional relationship of the drive device 1 of this embodiment mounted on a vehicle (not shown) located on a horizontal road surface. Furthermore, in the accompanying drawings, an XYZ coordinate system is appropriately shown as a three-dimensional Cartesian coordinate system.

[0028] In the figures, the Z-axis direction is the vertical direction. The +Z side is the upper vertical direction, and the -Z side is the lower vertical direction. In this embodiment, the upper vertical direction is simply referred to as the "upper side," and the lower vertical direction is simply referred to as the "lower side." The X-axis direction is orthogonal to the Z-axis direction and represents the front-rear direction of the vehicle on which the drive unit 1 is mounted. In this embodiment, the +X side is the front side of the vehicle, and the -X side is the rear side of the vehicle. The Y-axis direction is orthogonal to both the X-axis and Z-axis directions and represents the left-right direction of the vehicle, i.e., the vehicle width direction. In this embodiment, the +Y side is the left side of the vehicle, and the -Y side is the right side of the vehicle. The Y-axis direction corresponds to the axial direction of the third axis J3 described later. The front-rear and left-right directions of the vehicle are horizontal directions orthogonal to the vertical direction. In this embodiment, the +Y side corresponds to one side of the axial direction, and the -Y side corresponds to the other side of the axial direction. The third axis J3, appropriately shown in each figure, extends along the Y-axis direction, i.e., the left-right direction of the vehicle.

[0029] Figure 1 This is a schematic diagram illustrating the concept of the drive unit 1. 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 their power source.

[0030] The drive unit 1 includes a motor (power unit) 2, a gear unit (transmission mechanism) 3 including a reduction gear 4 and a differential gear 5, a parking mechanism 8, and a housing 6. The drive motor 2 drives the vehicle. The gear unit 3 is connected to the drive motor 2. The parking mechanism 8 is mounted on the gear unit 3.

[0031] The housing 6 has: a motor housing 61 for housing the drive motor 2; a gear housing 62 for housing the gear part 3 and the parking mechanism 8; and a partition wall 61c provided between the motor housing 61 and the gear housing 62.

[0032] The drive motor 2 rotates about a third axis J3 extending along a horizontal plane. The drive motor 2 includes a rotor 2a and a stator 2c. In this embodiment, the drive motor 2 is an internal rotor type motor. Therefore, the stator 2c surrounds the radially outer side of the rotor 2a.

[0033] Rotor 2a rotates about a third axis J3 extending in the horizontal direction. Rotor 2a has a motor shaft 2b extending axially about the third axis J3.

[0034] The motor shaft 2b rotates about the third axis J3. The motor shaft 2b extends across the motor housing 61 and the gear housing 62 of the housing 6. The left end of the motor shaft 2b protrudes into the gear housing 62. The first gear 41 of the gear section 3 is fixed to the left end of the motor shaft 2b.

[0035] The gear section 3 is housed in the gear receiving section 62 of the housing 6. The gear section 3 is connected to the drive motor 2. More specifically, the gear section 3 is connected to one axial side of the motor shaft 2b. The gear section 3 transmits power from the drive motor 2. The gear section 3 has a reduction gear 4 and a differential gear 5.

[0036] The reduction gear 4 is connected to the drive motor 2. The reduction gear 4 reduces the speed of the drive motor 2 and increases the torque output from the drive motor 2 according to the reduction ratio. The reduction gear 4 transmits the torque output from the drive motor 2 to the differential gear 5. The reduction gear 4 has a first gear 41, a second gear 42, a third gear 43, and an intermediate shaft 45. That is, the gear section 3 has a first gear 41, a second gear 42, a third gear 43, and an intermediate shaft 45.

[0037] The first gear 41 is fixed to the left end of the motor shaft 2b. The first gear 41 rotates together with the motor shaft 2b about the third axis J3. The intermediate shaft 45 extends along the fifth axis J5, which is parallel to the third axis J3. The intermediate shaft 45 rotates about the fifth axis J5. The second gear 42 and the third gear 43 are fixed to the outer circumferential surface of the intermediate shaft 45 with a axial gap between them. The second gear 42 and the third gear 43 are connected to each other via the intermediate shaft 45. The second gear 42 meshes with the first gear 41. The second gear 42 rotates about the fifth axis J5. The third gear 43 rotates together with the second gear 42 about the fifth axis J5. The third gear 43 meshes with the gear ring (fourth gear) 51 of the differential device 5.

[0038] The torque output from the drive motor 2 is transmitted sequentially to the gear ring 51 of the differential device 5 via the motor shaft 2b, the first gear 41, the second gear 42, the intermediate shaft 45, and the third gear 43. The gear ratio and number of gears in the reduction device 4 can be appropriately changed according to the required reduction ratio. In this embodiment, the reduction device 4 is a parallel shaft gear reducer with the shafts of each gear arranged in parallel.

[0039] The differential 5 is connected to the drive motor 2 via the reduction gear 4. The differential 5 is a device for transmitting torque output from the drive motor 2 to the wheels of the vehicle. When the vehicle turns, the differential 5 absorbs the speed difference between the left and right wheels and transmits the same torque to the axles 55 of both wheels. The differential 5 has a gear ring 51, a gear housing (not shown), a pair of pinions (not shown), a pinion shaft (not shown), and a pair of side gears (not shown). Specifically, the gear section 3 has a gear ring 51. The gear ring 51 meshes with the third gear 43 and rotates about a sixth axis J6 parallel to the third axis J3.

[0040] Furthermore, the axle 55 extends in a direction orthogonal to the vehicle's direction of travel (i.e., the width direction of the vehicle). Therefore, the direction of travel of the vehicle when the drive unit 1 is installed can be estimated based on the extension direction of the axle 55.

[0041] The parking mechanism 8 is located on the gear section 3 and restricts the drive of the gear section 3. The parking mechanism 8 is driven by the actuator 70. Through the actuator 70, which serves as a power source, the parking mechanism 8 switches between a locked state that prevents the rotation of the motor shaft 2b and an unlocked state that allows the rotation of the motor shaft 2b. When the vehicle is in the parking position, the parking mechanism 8 is locked; when the vehicle is in a position other than parking, the parking mechanism 8 is unlocked. Situations where the vehicle is in a position other than parking include, for example, driving, neutral, or reverse.

[0042] Figure 2 This is a 3D diagram of parking mechanism 8.

[0043] The parking mechanism 8 includes a parking gear 10, a pawl shaft 29, a parking pawl (brake component) 20, a cam rod 30, a cam 35, a coil spring 39, a bushing 80, a flange 90, and an actuator 70.

[0044] The parking gear 10 is fixed to the outer circumferential surface of the motor shaft 2b. The parking gear 10 is axially positioned between the first gear 41 and the partition wall 61c.

[0045] In this embodiment, the parking gear 10 is annular about a third axis J3 and engages with the outer circumferential surface of the motor shaft 2b. The parking gear 10 rotates together with the motor shaft 2b. That is, the parking gear 10 rotates around the third axis J3 in conjunction with the vehicle's wheels and the first gear 41. A plurality of teeth 11 arranged circumferentially are provided on the outer circumference of the parking gear 10. The teeth 11 protrude radially outward from the third axis J3. In the locked state described below, the teeth 11 engage with the engagement portion 25.

[0046] The pawl shaft 29 extends along a fourth axis J4 parallel to the third axis J3. That is, the pawl shaft 29 is a shaft parallel to the motor shaft 2b. The pawl shaft 29 supports the parking pawl 20 so that it can rotate.

[0047] A torsion spring 29a is mounted on the pawl shaft 29. The torsion spring 29a has a helical spring body and spring ends extending from both ends of the spring body. The pawl shaft 29 is inserted into the spring body of the torsion spring 29a. One spring end of the torsion spring 29a is hooked onto a spring hook portion (not shown) provided on the inner side of the housing 6. In addition, the other spring end of the torsion spring 29a is hooked into a spring hook hole 20h provided in the parking pawl 20. The torsion spring 29a applies a spring force to the parking pawl 20 in a direction that causes the front end to retract toward the bushing 80.

[0048] The parking pawl 20 is disposed on the side of the parking gear 10. The parking pawl 20 has a base end 22, a parking pawl body 21 extending obliquely downward from the base end 22, a cam contact portion 23, and an engagement portion 25.

[0049] Viewed axially from the third axis J3, the parking pawl body 21 is disposed between the parking gear 10 and the bushing 80. The parking pawl body 21 has a gear-facing surface 21a facing the parking gear 10 and a bushing-facing surface 21b facing the bushing 80. In this embodiment, the engagement portion 25 is located on the gear-facing surface 21a, and the cam contact portion 23 is located on the bushing-facing surface 21b. The cam contact portion 23 is located at the front end of the parking pawl 20. The engagement portion 25 is located between the base end portion 22 and the cam contact portion 23 in the longitudinal direction of the parking pawl 20.

[0050] The parking pawl 20 has a support hole 22h centered on the fourth axis J4 at its base end 22. A pawl shaft 29 is inserted into the support hole 22h. Thus, the parking pawl 20 is supported by the pawl shaft 29 at its base end 22 and can rotate about the fourth axis J4 via the pawl shaft 29.

[0051] The engaging portion 25 protrudes from the gear-facing surface 21a of the parking pawl main body 21 toward the parking gear 10. The engaging portion 25 is opposite to the teeth 11 of the parking gear 10. By rotating the parking pawl 20 around the pawl shaft 29, the engaging portion 25 moves toward and away from the parking gear 10.

[0052] The parking pawl 20 can be in any of the following states: locked, unlocked, or standby. The locked and unlocked states transition between each other as the operator performs actions. The standby state is present during the transition from the unlocked to the locked state when the operator performs an operation to switch from the unlocked to the locked state.

[0053] The locked state is a state in which the engaging part 25 engages with the parking gear 10, thus preventing the rotation of the parking gear 10. In the locked state of the parking mechanism 8, the engaging part 25 is engaged between the teeth 11 of the parking gear 10.

[0054] The unlocked state is a state in which the engaging part 25 is disengaged from the parking gear 10 and the lock is released, allowing the parking gear 10 to rotate. In the unlocked state of the parking mechanism 8, the engaging part 25 retracts radially outward from between the teeth 11 toward the third axis J3.

[0055] like Figure 6 As shown, the standby state is when the engaging part 25 is pressed against the teeth 11 of the parking gear 10, waiting to become locked. In the standby state, the parking gear 10 rotates, and when the gap of the teeth 11 matches that of the engaging part 25, the engaging part 25 engages with the teeth 11, changing to a locked state.

[0056] The cam contact portion 23 is disposed on the bushing-facing surface 21b of the parking pawl main body 21. The cam contact portion 23 is located inside the notch 83 of the bushing 80. The cam contact portion 23 functions as a force-bearing part of the cam 35. The parking pawl 20 rotates about the fourth axis J4 at the cam contact portion 23 due to the force from the cam 35. That is, the parking pawl 20 moves along with the movement of the cam 35.

[0057] Figures 3-5 This is a sectional view along the length of the cam rod 30. Figure 3 Indicates unlock status. Figure 4 Indicates a locked state. Figure 5 This indicates standby mode. Additionally, Figure 6 This is a front view of the parking pawl 20 and parking gear 10 of this embodiment, showing the standby state.

[0058] The cam contact portion 23 of the parking pawl 20 is opposite to the outer peripheral surface of the cam 35. The cam contact portion 23 is... Figure 3 In the unlocked state, it is separated from the outer peripheral surface of the cam 35. Furthermore, the cam contact portion 23... Figure 4 The locked state shown and Figure 5 In the standby state shown, the cam contact portion 23 contacts the outer peripheral surface of the cam 35. As the vehicle transitions from the unlocked state to the locked state, the cam contact portion 23 moves in coordination with the movement of the cam 35. The parking pawl 20 rotates around the fourth axis J4 along with the movement of the cam contact portion 23.

[0059] like Figure 2 As shown, the actuator 70 extending along the first axis J1 includes a motor 79, a worm gear 73, a counterspindle gear 74, an output gear 75, a manual shaft 71, a housing 72, and a rotation sensor 76. In this embodiment, the power of the motor 79 is transmitted in the order of the worm gear 73, the counterspindle gear 74, the output gear 75, and the manual shaft 71.

[0060] The motor 79 has a rotation shaft 79a extending along a seventh axis (axis) J7 orthogonal to the first axis J1. The rotation shaft 79a rotates about the seventh axis J7. The motor 79 is controlled by a control unit (not shown) based on the measured value of the rotation sensor 76.

[0061] The worm gear 73 is disposed on the outer peripheral surface of the rotating shaft 79a. The worm gear 73 is integrally disposed with the rotating shaft 79a. However, the worm gear 73 may also be a different component fixed to the outer peripheral surface of the rotating shaft 79a.

[0062] The counterspindle gear section 74 includes a worm gear 74a, a minor gear 74b, and a shaft section 74c. The counterspindle gear section 74 is a gear member centered on an eighth axis (axis) J8, which is parallel to the first axis J1. The eighth axis J8 is orthogonal to the seventh axis J7. The worm gear 74a, minor gear 74b, and shaft section 74c can be parts of a single component or separate components fixed to each other.

[0063] The shaft portion 74c of the secondary shaft gear section 74 extends along the eighth axis J8. The worm gear 74a is a helical gear centered on the eighth axis J8. The worm gear 74a meshes with the worm gear 73 and rotates about the eighth axis J8. The minor diameter gear 74b is a smaller gear with a diameter greater than that of the worm gear 74a. The minor diameter gear 74b is a spur gear centered on the eighth axis J8. The minor diameter gear 74b rotates together with the worm gear 74a about the eighth axis J8.

[0064] The output gear section 75 is fixed to the outer circumferential surface of the manual shaft 71, meshes with the small diameter gear 74b, and rotates about the first axis J1. The output gear section 75 has a sector gear 75a and a fixed cylinder section 75b. The sector gear 75a is a spur gear shaped like a sector centered on the first axis J1. The output gear section 75 meshes with the small diameter gear 74b at the sector gear 75a. The fixed cylinder section 75b is cylindrical and centered on the first axis J1. The manual shaft 71 is inserted into and fixed to the fixed cylinder section 75b.

[0065] The housing 72 houses the motor 79, the worm gear 73, the counterspindle gear 74, and the output gear 75. Furthermore, the housing 72 houses the base portion of the manual shaft 71. The manual shaft 71 extends through the inside and outside of the housing 72. The housing 72 is disposed within the outer casing 6 (see reference). Figure 1 The outside of ).

[0066] The housing 72 has a facing wall 72a opposite to the front end 79b of the rotating shaft 79a. An opening 72w is provided in the facing wall 72a. That is, the housing 72 has an opening 72w. The opening 72w extends through the facing wall 72a along its thickness direction. The opening 72w exposes the front end 79b of the rotating shaft 79a to the outside of the housing 72. A cover (not shown) is installed on the housing 72 to cover the opening 72w.

[0067] According to this embodiment, through the opening 72w of the open housing 72, an operator can approach the front end 79b of the rotating shaft 79a without disassembling the housing 72. This allows the front end 79b of the rotating shaft 79a to be rotated, driving the manual shaft 71 via gears. The structure of the front end 79b used to rotate the rotating shaft 79a will be explained in the following paragraphs. Figure 9 and Figure 10 Please provide an explanation.

[0068] The manual shaft 71 is cylindrical, centered on the first axis J1. The manual shaft 71 and the output gear 75 rotate together around the first axis J1. That is, the manual shaft 71 rotates around the first axis J1 under the power of the motor 79.

[0069] Manual shaft 71 is in housing 6 (refer to) Figure 1 The manual shaft 71 extends inside and outside the housing 6 and is connected to the flange 90 inside the housing 6. It is inserted into the housing 72 outside the housing 6 and connected to the output gear 75.

[0070] like Figure 2 As shown, in this embodiment, the manual shaft 71 and the pawl shaft 29 extend orthogonally to each other. That is, the pawl shaft 29 extends along a fourth axis J4 orthogonal to the first axis J1. According to this embodiment, compared to the case where the manual shaft 71 and the pawl shaft 29 extend parallel to each other, the shafts can be arranged in a three-dimensional manner, and the parking mechanism 8 can be miniaturized as a whole.

[0071] The pawl shaft 29 is arranged parallel to the axis of rotation of the parking gear 10 on the side of the parking gear 10. Therefore, the parking pawl 20 extends in the left-right direction of the vehicle, and the manual shaft 71 extends in the front-rear direction of the vehicle.

[0072] According to this embodiment, by extending the manual shaft 71 and the pawl shaft 29 orthogonally to each other, the direction of extension of the manual shaft 71 can be set to the longitudinal direction of the vehicle. Therefore, the driving direction of the flange 90 and the cam lever 30 driven by the manual shaft 71 becomes the left-right direction of the vehicle. According to this embodiment, the influence of inertial forces accompanying rapid acceleration and sudden stopping of the vehicle on the operation of the flange 90 and the cam lever 30 can be suppressed.

[0073] In this embodiment, the manual shaft 71 is disposed on the lower side of the pawl shaft 29. Therefore, the area on the lower side of the pawl shaft 29 can be effectively used as an area for the manual shaft 71 to pass through, and the parking mechanism 8 can be miniaturized.

[0074] A rotation sensor 76 is mounted on the output gear section 75. The rotation sensor 76 measures the rotation angle of the output gear section 75 and the manual shaft 71. The rotation sensor 76 is connected to a control unit (not shown) that controls the motor 79.

[0075] In this embodiment, a worm gear 73 and a worm wheel 74a are arranged in the power transmission path of the actuator 70. This increases the self-holding torque of the actuator 70. Here, self-holding torque refers to the maximum torque that can suppress the rotation of the internal mechanism relative to the torque input from the output side. In the actuator 70 of this embodiment, the self-holding torque is the torque input to the manual shaft 71 about the first axis J1, and is the torque at which the manual shaft 71 begins to rotate.

[0076] In the power transmission path with worm gear 73 and worm wheel 74a, the power transmission loss from the output side to the input side is greater than the power transmission loss from the input side to the output side. Therefore, by having worm gear 73 and worm wheel 74a, the actuator 70 can improve its self-holding torque. That is, according to this embodiment, the self-holding torque of the actuator 70 can be improved with a simple structure. Because the actuator 70 has a sufficiently large self-holding torque, it can maintain the rotation angle of the manual shaft 71 even when a large force is applied from the cam rod 30, as will be described in detail in the following paragraphs.

[0077] Furthermore, in this embodiment, the actuator 70 having a worm gear 73 and a worm wheel 74a is described, but the actuator 70 is not limited to this embodiment. Even without the worm gear 73 and worm wheel 74a, the actuator 70 can achieve the same effect as long as it has sufficient self-holding torque. Specifically, sufficient self-holding torque can be obtained as long as the reduction ratio of the power transmission path from the rotating shaft 79a to the manual shaft 71 is 1:100 or higher. Furthermore, the actuator 70 of this embodiment also satisfies the aforementioned reduction ratio.

[0078] A flange 90 is disposed on the outer peripheral surface of the manual shaft 71. In this embodiment, the flange 90 is a component different from the manual shaft 71 and is fixed to the outer peripheral surface of the manual shaft 71. However, the flange 90 may also be part of the manual shaft 71.

[0079] The flange 90 extends radially along the first axis J1. The flange 90 and the manual shaft 71 rotate together about the first axis J1. The flange 90 of this embodiment has: a flange body 91 extending radially along the first axis J1; and a protrusion 92 provided at the front end of the flange body 91. The protrusion 92 protrudes axially from the flange body 91 along the first axis J1.

[0080] The flange body 91 is plate-shaped and orthogonal to the first axis J1. A connecting hole 91h extending through the flange body 91 in the thickness direction is provided. The connecting portion 30a of the cam rod 30 passes through the connecting hole 91h. The connecting portion 30a of the cam rod 30 is rotatable about the connecting hole 91h.

[0081] The cam rod 30 has a connecting portion 30a, a relay portion 30b, and a rod body 30c. A first bend 31 is provided between the connecting portion 30a and the relay portion 30b, and a second bend 32 is provided between the relay portion 30b and the rod body 30c. The cam rod 30 bends at approximately 90° at both the first bend 31 and the second bend 32. The cam rod 30 is a rod with a circular cross-section, bent at both the first bend 31 and the second bend 32.

[0082] The connecting portion 30a extends axially along the first axis J1. Therefore, the connecting portion 30a extends parallel to the manual shaft 71. The connecting portion 30a is inserted into the connecting hole 91h of the flange 90. Thus, the connecting portion 30a is rotatably connected to the flange 90 relative to the flange 90. That is, the cam rod 30 is supported by the flange 90 at the connecting portion 30a and is rotatable. A protrusion is provided on the outer periphery of the connecting portion 30a to prevent the connecting portion 30a from disengaging from the connecting hole 91h.

[0083] The rod body 30c extends axially along a second axis J2 that is substantially parallel to the third axis J3. The second axis J2 is orthogonal to the first axis J1. Therefore, the rod body 30c extends in a direction orthogonal to the connecting portion 30a. The rod body 30c passes through the interior of the bushing 80. The rod body 30c is guided by the bushing 80. That is, the cam rod 30 is supported by the bushing 80 at the rod body 30c. Furthermore, the cam rod 30 moves along the second axis J2 along with the movement of the flange 90 (i.e., rotation about the first axis J1). In addition, in the unlocked state, the rod body 30c is slightly inclined relative to the second axis J2 (see reference). Figure 3 ).

[0084] The relay section 30b extends axially in a direction orthogonal to the first axis J1 and the second axis J2 (vertical direction in this embodiment). Therefore, the relay section 30b is orthogonal to both the connecting section 30a and the rod body 30c. The upper end of the relay section 30b is connected to the connecting section 30a. Furthermore, the lower end of the relay section 30b is connected to the rod body 30c. The relay section 30b connects the connecting section 30a and the rod body 30c.

[0085] The relay section 30b extends toward the third axis J3 when viewed axially from the third axis J3. The relay section 30b is designed to offset the vertical relative positions of the connecting section 30a and the rod body 30c. By arranging the relay section 30b to extend toward the third axis J3, the connecting section 30a can be arranged closer to the third axis J3 relative to the rod body 30c. Therefore, the cam 35 supported on the rod body 30c can be positioned optimally, and the flange 90, manual shaft 71, and actuator connected to the connecting section 30a can be arranged closer to the third axis J3. This allows for a dense arrangement of the various parts of the parking mechanism 8 around the third axis J3, reducing the space required for the parking mechanism 8 within the drive unit 1.

[0086] like Figures 3-5 As shown, the helical spring 39, cam 35, and cap 38 are passed through the rod body 30c. That is, the helical spring 39, cam 35, and cap 38 are mounted on the rod body 30c.

[0087] In the following description, the end of the rod body 30c that is connected to the relay part 30b is referred to as the base end 30cb, and the end on the opposite side of the base end is referred to as the front end 30ca.

[0088] A coil spring 39 is positioned relative to a cam 35 at the base end 30cb of the rod body 30c. A protrusion 30cc, larger than the inner diameter of the coil spring 39, is provided on the outer periphery of the base end 30cb of the rod body 30c. The coil spring 39, in a compressed state relative to its natural length, is positioned between the protrusion 30cc and the cam 35. The coil spring 39 exerts a force on the cam 35 toward the front end 30ca of the rod body 30c.

[0089] Cap 38 is fixed to the front end 30ca of the rod body 30c. Cap 38 is positioned on the rod body 30c at a position closer to the front end 30ca than cam 35. Cap 38 contacts the end face of cam 35. Cap 38 restricts the movement of cam 35 relative to the rod body 30c towards the front end 30ca. Cap 38 prevents cam 35 from detaching from the front end 30ca of the rod body 30c.

[0090] The cam 35 is annular with the rod body 30c at its center. The rod body 30c is inserted through a central through hole in the cam 35. The inner diameter of the through hole in the cam 35 is larger than the outer diameter of the rod body 30c. The cam 35 is sandwiched between the coil spring 39 and the cap 38 along the length of the rod body 30c. The coil spring 39 is compressed as the cam 35 moves toward the base end 30cb. When the cam 35 is subjected to a force stronger than the repulsive force of the coil spring 39 toward the base end 30cb, the cam 35 compresses the coil spring 39 and moves it toward the base end 30cb relative to the rod body 30c.

[0091] The cam 35 contacts the cam contact portion 23 of the parking pawl 20 on its outer peripheral surface. A first conical surface 35a and a second conical surface 35b are provided on the outer peripheral surface of the cam 35. The first conical surface 35a and the second conical surface 35b are arranged coaxially. The first conical surface 35a and the second conical surface 35b are conical surfaces whose outer diameter gradually decreases from the base end 30cb side of the rod body 30c towards the front end 30ca side. The second conical surface 35b is located on the front end 30ca side relative to the first conical surface 35a. The cone angle of the first conical surface 35a is much smaller than that of the second conical surface 35b. The cone angle of the second conical surface 35b is a sufficient angle for the cam 35 to smoothly disengage from the bushing 80 and the cam contact portion 23 when transitioning from the locked state to the unlocked state. Alternatively, the first conical surface 35a may be a cylindrical surface rather than a conical one.

[0092] The movement of the lever body 30c is transmitted to the cam 35 via the coil spring 39. As a result, the cam 35 moves together with the lever body 30c along the second axis. Furthermore, the cam 35 contacts the cam contact portion 23 of the parking pawl 20 on its outer peripheral surface. The cam 35 moves in tandem with the movement of the cam lever 30, thereby actuating the parking pawl 20.

[0093] like Figure 3 As shown, in the unlocked parking mechanism 8, the second conical surface 35b of the cam 35 faces the cam contact portion 23 of the parking pawl 20 with a gap between them. Furthermore, as... Figure 4 As shown, in the locked state of the parking mechanism 8, the cam 35 contacts the cam contact portion 23 at the first conical surface 35a. When the state of the parking mechanism 8 switches between the locked and unlocked states, the cam 35 contacts the cam contact portion 23 at the second conical surface 35b, and then slides. As a result, the cam 35 moves the cam contact portion 23 upward, causing the parking pawl 20 to rotate around the fourth axis J4.

[0094] like Figure 5 As shown, in the parking mechanism in standby mode, the cam 35 contacts the cam contact portion 23 at the second conical surface 35b. Figure 6 As shown, the standby state is when the engaging part 25 presses against the outer peripheral surface of the teeth 11 of the parking gear 10. Figure 5 As shown, the parking pawl 20 is in the following state: even if the cam lever 30 moves to the locked position, the cam 35 cannot move, and the cam 35 presses against the cam contact portion 23. As a result, the coil spring 39 is compressed between the cam 35 and the protrusion 30cc of the lever body 30c. The coil spring 39 presses the cam 35 against the cam contact portion 23 until the parking gear 10 rotates and the meshing portion 25 engages with the teeth 11. The coil spring 39 is most compressed in the standby state.

[0095] Figure 4 and Figure 5 The diagram shows the natural length Ln of the helical spring 39. As described above, the helical spring 39 is assembled to the rod body 30c in a compressed state. Figure 4 As shown, the coil spring 39 in its initial assembly state is compressed only by Xa to become length La. Furthermore, as... Figure 5 As shown, the coil spring 39 in the standby state is compressed to a length Lb by the maximum compression amount Xb. That is, the coil spring 39 is compressed to the maximum compression amount Xb when the engagement part 25 is pressed against the outer peripheral surface 11a of the tooth part 11 (standby state).

[0096] The bushing 80 is cylindrical, extending along the second axis J2. The front end 30ca of the rod body 30c is inserted into the bushing 80. The bushing 80 is cylindrical, surrounding the rod body 30c. The bushing 80 has a notch 83 that opens radially outward on a portion of its inner side 81. The bushing 80 is fixed to the inner side of the housing 6. The bushing 80 guides the movement of the rod body 30c and the cam 35.

[0097] Figure 7 This is a side view of a portion of the parking mechanism 8 of this embodiment, viewed from the axial direction of the first axis J1.

[0098] like Figure 7 As shown, an imaginary perpendicular line P is defined from the first axis J1 to the second axis J2 when viewed along the axial direction of the first axis J1. The perpendicular line P is orthogonal to the second axis J2. In this embodiment, the first axis J1 and the second axis J2 extend horizontally, so the perpendicular line P extends vertically. Alternatively, the perpendicular line P may not necessarily extend vertically.

[0099] An imaginary line VL is defined to connect the first axis J1 and the center point of the connection portion 30a of the cam rod 30 when viewed axially from the first axis J1. The connection portion 30a moves about the first axis J1 as the manual shaft 71 rotates. Therefore, the connection portion 30a moves along an imaginary circle VC centered on the first axis J1 as the flange 90 moves.

[0100] Let θ be the angle between the imaginary line VL and the perpendicular line P. That is, when viewed from the axial direction of the first axis J1, let θ be the angle between the perpendicular line P and the connecting part 30a. The angle θ changes as the connecting part 30a moves along the imaginary circle VC. The connecting part 30a moves about the first axis J1 relative to the perpendicular line P within a range of ±45°. Therefore, the angle θ is an angle of ±45° or less. In addition, here, the range of movement of the connecting part 30a (±45°) is only the maximum range, and the connecting part 30a moves within a narrower range of motion within this range.

[0101] When viewed axially from the first axis J1, the distance between the first axis J1 and the connecting part 30a is set to R. The distance R is the radius of the imaginary circle VC. Furthermore, the spring constant of the helical spring 39 is set to k. Furthermore, the maximum compression of the helical spring 39 within the movable range of the rod body 30c is set to Xb. Moreover, the self-holding torque of the actuator 70 is set to Ts.

[0102] Given the spring constant k, maximum compression Xb, distance R, and angle θ as set above, the following Equation 1 holds as the self-holding torque Ts of the actuator 70 in this embodiment.

[0103] [Mathematical Expression 1]

[0104] Ts>k·Xb·R·cosθ …(Equation 1)

[0105] The right side of Equation 1 represents the maximum torque that can be input from the cam lever 30 to the manual shaft 71. The manual shaft 71 receives torque from the cam lever 30 when the coil spring 39 is compressed. Therefore, the maximum torque is imparted to the manual shaft 71 when the parking pawl 20 is in standby mode and the coil spring 39 is compressed to its maximum compression amount Xb.

[0106] A reaction force Fsp from the helical spring 39 is applied to the connecting part 30a. The reaction force Fsp is expressed as the product of the maximum compression Xb of the helical spring 39 and the spring constant k of the helical spring 39. The reaction force Fsp forms an angle θ with respect to the tangent direction of the imaginary circle VC. Therefore, the maximum torque applied to the manual shaft 71 is the value of Fsp multiplied by cosθ (the right side of Equation 1).

[0107] According to this embodiment, the actuator 70 has a self-holding torque Ts that is greater than the maximum torque that can be input from the cam rod 30 to the manual shaft 71. Therefore, even if the actuator 70 receives torque from the cam rod 30, it can maintain the rotation angle of the manual shaft 71 without causing the manual shaft 71 to rotate.

[0108] The parking mechanism 8 according to this embodiment does not require a positioning structure such as a leaf spring to position the rotation angle of the manual shaft 71. Therefore, according to this embodiment, not only can the number of parts be reduced, but the parking mechanism 8 can also be miniaturized.

[0109] Furthermore, according to the parking mechanism 8 of this embodiment, compared with the case where a positioning structure such as a leaf spring is required, the manual shaft 71 can be rotated without resisting the elastic force of the leaf spring, thus achieving power saving of the actuator 70.

[0110] According to the actuator 70 of this embodiment, the reduction ratio of the power transmission path from the rotating shaft 79a to the manual shaft 71 is 1:100 or higher. This ensures the aforementioned self-holding torque Ts. Furthermore, by achieving such a large reduction ratio, the actuator 70 can impart a large force to the cam rod 30.

[0111] When the parking pawl 20 is moved from the locked state to the unlocked state, the force received from the cam contact portion 23 of the parking pawl 20 may cause the cam 35 to engage. According to this embodiment, the actuator 70 can apply a large force to the cam rod 30, thus easily eliminating the engagement of the cam 35. Furthermore, when the parking gear 10 is fixed to a shaft that transmits high torque, the force generated on the cam 35 when it engages tends to increase. According to this embodiment, because it has a structure that easily eliminates the engagement of the cam 35, it is easy to fix the parking gear 10 to a shaft that transmits high torque (e.g., an intermediate shaft 45 (see reference)). Figure 1 The structure of )).

[0112] Figure 7 The outer diameter of the housing 72 of the actuator 70 is illustrated by a double-dotted line. (See diagram below.) Figure 7 As shown, the dimension of the actuator 70 in the direction in which the vertical line P extends (in this embodiment, the up-down direction) is set as the height dimension h. In this embodiment, the distance R between the first axis J1 and the connecting portion 30a, viewed from the axial direction of the first axis J1, is smaller than the height dimension h of the actuator. Therefore, a compact parking mechanism 8 can be provided relative to the size of the actuator 70 without making the flange 90 excessively large.

[0113] In this embodiment, the connecting portion 30a of the cam rod 30 moves within a range of ±45° relative to the vertical line P about the first axis J1. That is, the angle θ is an angle within a range of ±45°. The travel distance of the cam rod 30 along the second axis J2 is represented by R·sinθ. By making the range of angle θ ±45°, the travel distance of the cam rod 30 can be ensured to be sufficiently large relative to the rotation angle of the manual shaft 71.

[0114] Next, the structure of the protrusion 92 of the flange 90 will be explained in more detail.

[0115] like Figure 2 As shown, the protrusion 92 is disposed on the side of the parking gear 10 relative to the relay part 30b in the axial direction of the second axis J2, and is disposed overlapping with the relay part 30b when viewed from the axial direction of the second axis J2.

[0116] The protrusion 92 has a facing surface 92f opposite to the relay portion 30b. The facing surface 92f faces the relay portion 30b with a gap in the axial direction of the second axis J2. A groove 92g extending along the extending direction of the relay portion 30b (vertical direction in this embodiment) is provided on the facing surface 92f. That is, the protrusion 92 has a groove 92g located on the facing surface 92f. In addition, the protrusion 92 in this embodiment is plate-shaped, so the groove 92g is notched.

[0117] Here, as Figure 7 As shown by the double-dotted line, imagine a scenario where the connecting hole 191h provided in the flange 90 is sufficiently large relative to the outer periphery of the connecting portion 30a of the cam rod 30. In this case, the cam rod 30 can move relative to the flange 90 along the second axis J2 by ​​the amount of looseness between the connecting hole 191h and the connecting portion 30a. Furthermore, the amount of looseness between the connecting hole 191h and the connecting portion 30a along the second axis J2 is greater than the distance between the relay portion 30b and the protrusion 92 in the direction along the second axis J2. Therefore, the way force is transmitted from the flange 90 to the cam rod 30 changes depending on whether the flange 90 rotates circumferentially. That is, when the flange 90 rotates circumferentially... Figure 7 When rotated counterclockwise, the inner surface of the cam rod 30 is facing the connecting hole 191h. Figure 7 Push up from the right side. On the other hand, when the flange is 90 degrees... Figure 7 When rotated clockwise, the cam rod 30 is turned towards the opposite side of the relay part 30b. Figure 7 Push the top from the left side.

[0118] With the above structure, the cam rod 30, along with the flange 90, circumferentially moves around the first axis J1 on one side. Figure 7 The rotating movement (counterclockwise) causes it to contact the flange body 91 at the connecting part 30a, and moves along the second axis J2 toward the parking gear 10 side. Figure 7 (Right side) moves. Furthermore, the cam rod 30 moves circumferentially around the first axis J1 to the other side ( ) of the flange 90. Figure 7 The rotational movement (clockwise) causes it to contact the protrusion 92 at the intermediate part 30b, and moves along the second axis J2 towards the opposite side of the parking gear 10. Figure 7 Move to the left side of the middle.

[0119] According to the above structure, the point of application of the force transmitted from the flange 90 to the cam rod 30 can be changed when the cam rod 30 is moved toward the parking gear 10 and when it is moved toward the opposite side of the parking gear 10. More specifically, when the cam rod 30 is moved toward the opposite side of the parking gear 10 ( Figure 7 When the cam rod 30 moves to the left side (in the middle), compared to the case where it moves towards the parking gear 10, the point of action can be positioned further away from the first axis J1. Therefore, when the cam rod 30 is moved towards the side opposite to the parking gear 10 (in the middle left), the point of action can be positioned further away from the first axis J1. Figure 7 When the cam rod 30 is moved to the left side (middle left), it can be moved significantly with a small rotation angle. On the other hand, when the cam rod 30 is moved towards the parking gear 10 side ( Figure 7 When the right side moves, the cam rod 30 can be moved with a large force.

[0120] Furthermore, protrusion 92 is utilized in the assembly method of parking mechanism 8.

[0121] The assembly method of the parking mechanism 8 includes a flange fixing process, a cam rod connection process, and a bushing installation process. Here, we will mainly describe each of these processes.

[0122] exist Figure 2 Before performing the flange fixing process, cam rod connection process, and bushing installation process in the parking mechanism 8 shown, the following preparations are made in advance.

[0123] In the assembly method of the parking mechanism 8, firstly, the actuator 70 is assembled. Next, the actuator 70 is fixed to the housing 6 (see reference). Figure 1 The outer side of the housing 6. In addition, a ratchet shaft 29 and a parking ratchet 20 are installed on the inner side of the housing 6, and a parking gear 10 is installed on the gear section.

[0124] Figure 8 This is a side view illustrating the flange fixing process, cam rod connection process, and bushing installation process of the assembly method of the parking mechanism 8 in this embodiment. Additionally, Figure 8 The arrow U in the middle indicates the vertical direction upward in the assembly process.

[0125] The flange fixing process, cam rod connection process, and bushing installation process are performed sequentially. As described above, the actuator 70 is already fixed to the housing 6 before the flange fixing process. Therefore, the manual shaft 71 of the actuator 70 protrudes from the inner side of the housing 6 toward the inner side of the housing 6.

[0126] The flange fixing process is the process of fixing the flange 90 to the manual shaft 71. In the flange fixing process, the operator inserts the manual shaft 71 into the insertion hole 91a provided in the flange 90, and fixes them relative to each other by the fixing member 95.

[0127] The cam rod connection process involves connecting the cam rod 30 to the flange 90. Prior to the cam rod connection process, the helical spring 39, cam 35, and cap 38 are assembled onto the rod body 30c.

[0128] In the cam rod connection process, the operator inserts the connecting part 30a of the cam rod 30 into the connecting hole 91h provided in the flange 90 and connects them so that they can rotate. A protrusion is provided on the outer peripheral surface of the connecting part 30a of the cam rod, and a notch with approximately the same shape as the protrusion is provided on the inner edge of the connecting hole 91h. When the operator inserts the connecting part 30a into the connecting hole 91h, the protrusion of the connecting part 30a is inserted in a fitting manner with the notch of the connecting hole 91h, causing the connecting part 30a to rotate. This prevents the connecting part 30a from detaching from the flange 90.

[0129] The bushing installation procedure is the same as the procedure for installing bushing 80. For example... Figure 8 As shown, the bushing installation process is performed with the second axis J2 positioned along the vertical direction. That is, the bushing installation process is performed with the outer casing 6 tilted 90° from the horizontal direction toward the vertical direction.

[0130] In the bushing installation process, the protrusion 92 of the flange 90 is positioned below the relay portion 30b of the cam rod 30. During the bushing installation process, the operator inserts the front end 30ca of the rod body 30c into the bushing 80 from below, supporting the relay portion 30b via the protrusion 92. The operator then secures the bushing 80 to the inner surface of the housing 6.

[0131] During the bushing installation process, the relay part 30b is received in the groove 92g of the protrusion 92. As a result, the protrusion 92 not only supports the relay part 30b from below, but also stabilizes the relay part 30b, preventing the relay part 30b from detaching during the bushing installation process.

[0132] According to this embodiment, by providing a protrusion 92 on the flange 90, the cam rod 30, which is prone to instability during the assembly process, can be temporarily held in place by the protrusion 92. This allows for easy insertion of the front end 30ca of the rod body 30 into the bushing 80, simplifying the assembly process of the parking mechanism 8.

[0133] Furthermore, the aforementioned flange fixing process and cam rod connection process are preferably performed in the same orientation as the bushing installation process. This eliminates the need to change the orientation of the housing 6 during the process, thus reducing cycle time between processes.

[0134] Next, the structure of the rotation sensor 76 will be explained.

[0135] The parking mechanism 8 of this embodiment does not have a mechanical positioning mechanism for the rotation angle of the manual shaft 71. Therefore, the positioning of the rotation angle of the manual shaft 71 is electrically controlled based on the measurement results of the rotation sensor 76 provided on the output gear section 75. In this embodiment, the actuator 70 obtains the reference value of the rotation sensor 76 by performing an abutment process. The rotation sensor 76 outputs the rotation angle of the manual shaft 71 based on the relative angle with respect to the reference value.

[0136] like Figure 7 As shown, an abutment member 6a is provided on the inner side of the housing 6 housing the parking mechanism 8. In this embodiment, the abutment member 6a is a pin-shaped member fixed to the inner side of the housing 6. Alternatively, the abutment member 6a may also be a part of the inner side of the housing 6.

[0137] The abutting member 6a is opposite to the end face 91f of the flange 90 in the circumferential direction about the first axis J1. That is, the abutting member 6a is opposite to the flange 90 on the rotational trajectory of the flange 90.

[0138] The contacting process is the process of bringing the flange 90 into contact with the contacting member 6a. The flange 90 rotates toward the contacting member 6a along with the rotation of the manual shaft 71, thereby coming into contact with the contacting member 6a at its end face 91f.

[0139] The flange 90 contacts the abutment member 6a, thus restricting the rotation of the flange 90. A control unit (not shown), connected to the rotation sensor 76, determines that the flange 90 is in contact with the abutment member 6a when the measured value of the rotation sensor 76 becomes constant, and stores this value as a reference value. Furthermore, the control unit uses this reference value as a mechanical reference to control the rotation angle of the manual shaft 71.

[0140] According to this embodiment, the reference value of the rotation sensor 76 is derived using the abutment member 6a provided on the housing 6. Therefore, the measured value of the rotation sensor 76 can be measured with high accuracy based on the rotation angle from the abutment member 6a, regardless of the assembly accuracy of the rotation sensor 76 and the individual differences in the dimensional accuracy of each component, enabling the parking mechanism 8 to operate stably.

[0141] According to this embodiment, the abutment member 6a is disposed on the housing 6. The various parts of the parking mechanism 8 are assembled with the housing 6 as a reference. Therefore, by disposing of the abutment member 6a on the housing 6 as a reference for the rotation angle measured by the rotation sensor 76, it is easy to improve the relative position accuracy with other components and improve the measurement accuracy of the rotation sensor 76.

[0142] Next, the manual operation of actuator 70 will be explained.

[0143] like Figure 2 As shown, in the actuator 70 of this embodiment, the front end 79b of the rotating shaft 79a protrudes from the opening 72w of the housing 72. The operator can insert a tool through the opening 72w to rotate the rotating shaft 79a.

[0144] Figure 9 and Figure 10 These are perspective views showing tool connection portions 79c and 79d located at the front end 79b of the rotation axis 79a.

[0145] Figure 9 The tool connector 79c shown is a straight groove on the front end 79b of the rotating shaft 79a. This tool connector 79c can be connected to a flathead screwdriver. The operator can engage the tip of the flathead screwdriver with the tool connector 79c to rotate the rotating shaft 79a.

[0146] Figure 10 The tool connection 79d shown is an H-cutting part located at the front end 79b of the rotating shaft 79a. This tool connection 79d can be connected to a socket screwdriver that engages with the H-cutting part. The operator can rotate the rotating shaft 79a by engaging the tip of the socket screwdriver with the tool connection 79d.

[0147] According to this embodiment, a tool connection portion 79c, 79d that engages with a tool that rotates the rotating shaft 79a is provided at the front end 79b of the rotating shaft 79a. Because the actuator 70 of this embodiment has a large self-holding torque, the manual shaft 71 cannot be manually operated. According to this embodiment, the operator can directly rotate the rotating shaft 79a of the motor 79. Therefore, even with the actuator 70, which has a large self-holding torque, the state of the parking mechanism 8 (locked state or unlocked state) can be manually switched.

[0148] Furthermore, according to this embodiment, the operator directly rotates the rotating shaft 79a, thus enabling the switching of the parking mechanism 8 state with minimal torque. Therefore, small and versatile tools such as screwdrivers can be used as the tools connected to the tool connection portions 79c and 79d, improving maintainability. Moreover, according to this embodiment, since the operation of the rotating shaft 79a can be achieved with a small tool, the opening 72w for bringing the tool close to the tool connection portions 79c and 79d can be easily reduced, enabling miniaturization of the actuator 70.

[0149] Various embodiments of the present invention have been described above. However, each structure and combination thereof in each embodiment is an example, and structural additions, omissions, substitutions, and other changes can be made without departing from the spirit of the present invention. Moreover, the present invention is not limited to the embodiments.

[0150] For example, the power unit of the drive device 1 in this embodiment is a motor, but it may also be an engine. Furthermore, the structure of the gear unit (transmission mechanism) is not limited to the description in this embodiment.

Claims

1. A parking mechanism, comprising: An actuator having a manual shaft extending along and rotating about a first axis; A flange is disposed on the outer periphery of the manual shaft and extends radially along the first axis; A cam rod having a connecting portion and a rod body, the connecting portion being connected to the flange, and the rod body extending along a second axis orthogonal to the first axis and moving along the second axis following the movement of the flange; A helical spring, which is mounted on the rod body; A cam, which is mounted on the rod body, transmits the movement of the rod body via the helical spring, and moves along the second axis; A braking component having an engaging portion and actuating in conjunction with the movement of the cam; as well as A parking gear, the parking gear having teeth that mesh with the meshing portion, An imaginary perpendicular line is defined from the first axis toward the second axis when viewed along the axial direction of the first axis. The connecting portion can move within a range of ±45° relative to the vertical line around the first axis. Let the spring constant of the helical spring be k. Let Xb be the maximum compression of the helical spring within the movable range of the rod body. When viewed from the axial direction of the first axis, the distance between the first axis and the connecting portion is defined as R. When viewed from the axial direction of the first axis, the angle between the perpendicular line and the connecting portion is defined as θ. If the self-holding torque of the actuator is set to Ts, then Equation 1 below holds. [Mathematical Expression 1] Ts>k·Xb·R·cosθ …(Equation 1), The cam rod has a relay portion that connects the connecting portion and the rod body. The connecting portion extends in an axial shape along the first axis. The relay section extends axially in a direction orthogonal to the first axis. The flange has: A flange body extending radially along the first axis; as well as A protrusion is provided at the front end of the flange body and protrudes axially from the flange body along the first axis. The protrusion is disposed on one side of the parking gear relative to the relay portion in the axial direction of the second axis, and is disposed overlapping with the relay portion when viewed from the axial direction of the second axis. The cam rod As the flange rotates about one side of the first axis, it contacts the flange body at the connecting portion and moves along the second axis toward the parking gear. As the flange rotates around the first axis to the other side, it contacts the protrusion at the relay portion and moves along the second axis to the opposite side of the parking gear.

2. The parking mechanism according to claim 1, wherein, It has a bushing into which the front end of the rod body is inserted. The cam rod is rotatably supported on the flange at the connection and on the bushing at the rod body.

3. The parking mechanism according to claim 1 or 2, wherein, The actuator has: A motor having a rotational shaft extending in a direction orthogonal to the first axis; A worm gear is disposed on the outer periphery of the rotating shaft, and the motor causes the worm gear to rotate; A secondary shaft gear section, comprising a worm gear and a minor diameter gear, wherein the worm gear meshes with the worm gear, and the minor diameter gear rotates together with the worm gear about an axis parallel to the first axis; and The output gear is fixed to the outer circumferential surface of the manual shaft, meshes with the small diameter gear, and rotates around the first axis.

4. The parking mechanism according to claim 3, wherein, The reduction ratio of the power transmission path from the rotating shaft to the manual shaft of the actuator is 1:100 or higher.

5. The parking mechanism according to claim 3, wherein, The actuator has a housing that houses the motor, the worm gear, the countershaft gear section, and the output gear section. The housing has an opening that exposes the front end of the rotating shaft. A tool connecting part is provided at the front end of the rotating shaft, and the tool connecting part engages with a tool that rotates the rotating shaft.

6. The parking mechanism according to claim 1, wherein, The protrusion has a groove located on the opposite surface of the protrusion to the relay portion and extending along the extension direction of the relay portion.

7. The parking mechanism according to claim 1 or 2, wherein, It has a pawl shaft that extends along a fourth axis orthogonal to the first axis and supports the braking member so that it can rotate.

8. The parking mechanism according to claim 1 or 2, wherein, It includes an abutting member disposed in the housing that houses the parking mechanism and is opposite to the flange on the rotational trajectory of the flange.

9. The parking mechanism according to claim 1 or 2, wherein, The helical spring is compressed to the maximum compression amount Xb when the engaging part is pressed against the outer peripheral surface of the tooth.

10. The parking mechanism according to claim 1 or 2, wherein, The distance between the first axis and the connection portion, viewed from the axial direction of the first axis, is smaller than the size of the actuator in the direction of the vertical extension.

11. A method for assembling a parking mechanism, The parking mechanism is located on the drive unit. The parking mechanism is the parking mechanism according to any one of claims 1 to 10. The parking mechanism has a bushing into which the front end of the rod body is inserted. The protrusion extends from the flange body in a direction parallel to the first axis. The assembly method of the parking mechanism has the following characteristics: The process of connecting the cam rod to the flange; and The bushing installation procedure for installing the bushing. The bushing installation process is performed with the second axis positioned vertically, and the front end of the rod body is inserted into the bushing by supporting the relay part from below through the protrusion.

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