vehicle

Abstract

To prevent the parking pole from locking in a loosely engaged state. [Solution] The vehicle comprises a parking gear, a parking pawl attached to the first pivot shaft and configured to rotate between a first position in which it engages with the parking gear and a second position in which it disengages from the parking gear, a rod configured to move in the axial direction, and a cam attached to the rod and having a tapered surface that rotates the parking pawl from the second position to the first position by pressing the pressure-bearing surface formed on the parking pawl in a direction perpendicular to the axial direction in accordance with the axial movement of the rod. When the cam begins to contact the parking pawl due to the axial movement of the rod, if a portion of the tapered surface of the cam that contacts the pressure-bearing surface of the parking pawl is defined as the initial contact area, the center of gravity of the cam in the axial direction is located within the initial contact area.

Description

Technical Field

[0001] The present invention relates to a vehicle.

Background Art

[0002] Conventionally, a vehicle has been provided with a parking device that meshes a parking pawl with a parking gear to restrict the rotation of the parking gear in order to maintain the parked state of the vehicle. For example, Patent Document 1 discloses a parking device including a rod that is driven forward and backward by an actuator, and a cam that is attached to the rod and moves the parking pawl between a meshing position and a non-meshing position with the parking gear.

[0003] According to the parking device of Patent Document 1, the parking pawl is moved from the non-meshing position to the meshing position by driving the rod and the cam by an actuator. Thereby, the parking pawl meshes with the parking gear, and the rotation of the parking gear can be restricted.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, when the parking pawl is moved from the non-meshing position to the meshing position, the parking gear and the parking pawl may lock in a shallow meshing state. In that case, if the parking pawl in the shallow meshing state is forcibly moved toward the meshing position in order to mesh it with the parking gear, the movement of the parking pawl is restricted by the teeth of the parking gear, so there is a risk that the parking pawl will be damaged.

[0006] Therefore, the present invention aims to prevent the parking pole from locking in a loosely engaged state. [Means for solving the problem]

[0007] To solve the above problems, a vehicle according to one embodiment of the present invention is provided. Parking gear and, A parking pawl is mounted on the first drive shaft and is configured to rotate between a first position in which it engages with the parking gear and a second position in which it is disengaged from the parking gear. A rod configured to be movable in the axial direction, A cam having a tapered surface is attached to the rod and rotates the parking pole from the second position to the first position by pressing a pressed surface formed on the parking pole in a direction perpendicular to the axial direction in accordance with the axial movement of the rod, Equipped with, When the cam begins to contact the parking pole due to the axial movement of the rod, if a portion of the tapered surface of the cam that contacts the pressed surface of the parking pole is defined as the initial contact region, then the center of gravity of the cam in the axial direction is located within the range of the initial contact region. [Effects of the Invention]

[0008] According to the present invention, it is possible to prevent the parking pole from locking in a loosely engaged state. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a block diagram showing an example of the configuration of a vehicle according to the first embodiment. [Figure 2] Figure 2 is a schematic diagram showing an example of the configuration of a shift device according to the first embodiment. [Figure 3] Figure 3 is a schematic diagram showing an example of the configuration of a parking device according to the first embodiment. [Figure 4]Figure 4 is an XZ cross-sectional view at the position of the rod of the parking device shown in Figure 3. [Figure 5] Figure 5 is an XZ cross-sectional view of the parking device with the rod shown in Figure 4 moved in the +X direction. [Figure 6] Figure 6 is a schematic diagram showing the configuration of the parking device 300 when the parking pole shown in Figure 3 is pressed in the +Z direction. [Figure 7] Figure 7 is an XZ cross-sectional view of the cam according to the first embodiment. [Figure 8] Figure 8 is an XZ cross-sectional view of the cam according to the second embodiment. [Figure 9] Figure 9 is an XZ cross-sectional view of the cam according to the third embodiment. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described in detail below with reference to the attached drawings. The specific dimensions, materials, numerical values, etc., shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0011] Figure 1 is a block diagram showing an example of the configuration of a vehicle 1 according to the first embodiment. Vehicle 1 is, for example, a hybrid vehicle having an engine and a motor as drive sources (not shown). However, it is not limited to this, and vehicle 1 may be, for example, an engine-powered vehicle having only an engine as a drive source, or an electric vehicle having only a motor as a drive source. The driving force generated by the drive sources is transmitted to the wheels (not shown) via the transmission (not shown) of vehicle 1.

[0012] As shown in FIG. 1, the vehicle 1 has a shift device 100, a drive mechanism 200, and a parking device 300. The shift device 100 is a device that switches the shift range of the transmission of the vehicle 1 by operating the shift lever 110. The drive mechanism 200 is a mechanism that drives the parking device 300 according to the operation of the shift lever 110. The parking device 300 is a device that restricts the rotation of the wheels of the vehicle 1.

[0013] FIG. 2 is a schematic diagram showing an example of the configuration of the shift device 100 according to the first embodiment. As shown in FIG. 2, the shift device 100 includes a shift lever 110 for switching the shift range of the transmission mounted on the vehicle 1. The shift lever 110 is an example of an operating member operated by a driver boarding the vehicle 1. In FIG. 2, the Z direction indicates the vertical direction, the X direction indicates a predetermined direction in the horizontal direction, and the Y direction indicates a direction orthogonal to the X direction in the horizontal direction. The X direction is, for example, the forward and backward driving direction of the vehicle 1, and the Y direction is, for example, the left and right direction of the vehicle 1.

[0014] In the shift device 100, the shift lever 110 is configured to be switchable to, for example, a parking range (P range) 120, a reverse range (R range) 130, a neutral range (N range) 140, and a drive range (D range) 150.

[0015] The P range 120 is selected when the vehicle 1 is stopped or parked. The R range 130 is selected when the vehicle 1 is driven in the reverse direction. The N range 140 is a range in which the vehicle 1 does not move forward, backward, or shift gears, and is selected when disconnecting the driving force transmitted from the drive source of the vehicle 1 to the wheels. The D range 150 is selected when the vehicle 1 is driven in the forward direction.

[0016] As positions of the shift lever 110 for selecting each range in the shift device 100, a P range 120, an R range 130, an N range 140, and a D range 150 are provided on a linear path 160 extending in a direction D1. In the first embodiment, the direction D1 is, for example, the X direction. By the driver operating the shift lever 110 in the direction D1, the range selectable by the shift device 100 is switched.

[0017] The drive mechanism 200 drives the parking device 300 according to the position of the shift lever 110. Details of the drive mechanism 200 will be described later.

[0018] FIG. 3 is a schematic diagram showing an example of the configuration of the parking device 300 according to the first embodiment. FIG. 4 is an XZ cross-sectional view at the position of the rod 330 of the parking device 300 shown in FIG. 3. As shown in FIGS. 3 and 4, the parking device 300 includes a parking gear 310, a parking pole 320, a rod 330, a cam 340, and a coil spring 350.

[0019] The parking gear 310 is provided on the power transmission shaft 312 of the transmission of the vehicle 1. The power transmission shaft 312 is, for example, the output shaft of the transmission. The power transmission shaft 312 is a shaft member extending in the X direction. The power transmission shaft 312 transmits the driving force generated by the drive source of the vehicle 1 to the wheels and rotates in conjunction with the wheels. Also, the parking gear 310 rotates integrally with the power transmission shaft 312. Therefore, the parking gear 310 rotates in conjunction with the wheels of the vehicle 1 via the power transmission shaft 312.

[0020] The parking gear 310 is provided with a plurality of teeth 314. The plurality of teeth 314 are provided at equal intervals on the outer periphery of the parking gear 310. However, it is not limited thereto, and the plurality of teeth 314 may be provided at unequal intervals on the outer periphery of the parking gear 310.

[0021] The parking pawl 320 has the function of restricting the rotation of the wheels by meshing with the parking gear 310. The parking pawl 320 is, for example, a rod-shaped member extending in the Y direction. The parking pawl 320 is formed, for example, by press-forming a sheet material such as a metal plate. The parking pawl 320 is rotatably mounted on a shaft 322. The shaft 322 is an example of a first pivot shaft to which the parking pawl 320 is mounted. The shaft 322 is, for example, a shaft member extending in the X direction and is provided in the transmission of the vehicle 1. The shaft 322 is attached to the first end 320a of the parking pawl 320 in the Y direction. The parking pawl 320 is positioned below the parking gear 310 in the Z direction. In addition, at least a portion of the upper surface of the parking pawl 320 is positioned to face the lower side of the outer circumferential surface of the parking gear 310.

[0022] The parking pawl 320 is subjected to a biasing force in the direction away from the parking gear 310, that is, in the direction closer to the rod 330 and cam 340. For example, the parking pawl 320 is subjected to a biasing force in the direction away from the parking gear 310 (counterclockwise direction in Figure 3) by an elastic member such as a coil spring (not shown).

[0023] The parking pole 320 is provided with a projection 324. The projection 324 is provided on the surface of the parking pole 320 that faces the parking gear 310 in the Z direction (for example, the upper surface in Figure 3), and is provided to protrude in the Z direction. The projection 324 has the function of locking the parking gear 310 by meshing with the teeth 314 of the parking gear 310.

[0024] The rod 330 has the function of moving the cam 340 in response to the operation of the shift lever 110. The rod 330 is, for example, a rod member with a circular cross-section extending in the X direction. The rod 330 is positioned below the second end 320b in the Y direction of the parking pole 320 in the Z direction. The first end 320a of the parking pole 320 is the end of the parking pole 320 that is pivotally attached to the shaft 322. The second end 320b of the parking pole 320 is the end provided on the opposite side from the first end 320a. The rod 330 is configured to be movable in the axial direction, which is the X direction. Hereinafter, the axial direction of the rod 330 may be simply referred to as the "axial direction". In the first embodiment, the rod 330 is connected to the drive mechanism 200 and driven in the X direction by the drive mechanism 200.

[0025] The cam 340 has the function of moving the parking pole 320 to a first position and a second position in response to the drive of the rod 330. The cam 340 is, for example, a cylindrical member. The cam 340 has a through hole 340a through which the rod 330 is inserted in the axial direction. The cam 340 is attached to the outer circumferential surface of the rod 330 and is configured to slide axially (in the X direction) on the outer circumferential surface of the rod 330. A portion of the cam 340 is positioned to overlap with the parking pole 320 in the Z direction.

[0026] The cam 340 includes a cylindrical portion 342 having a constant outer diameter and a tapered portion 344 having an outer diameter that gradually increases in the axial direction (X direction). The tapered portion 344 is provided on the -X direction side relative to the cylindrical portion 342. The outer diameter of the tapered portion 344 gradually increases in the -X direction. The outer circumferential surface of the tapered portion 344 has a tapered surface 346. In the first embodiment, a recessed portion 348 that is recessed in the +X direction is formed in the center of the -X direction end of the cam 340.

[0027] The second end 320b of the parking pole 320 has an inclined surface 326 on the -X direction side. The inclined surface 326 of the parking pole 320 is an example of a pressed surface that abuts against and is pressed against the tapered surface 346 of the cam 340. The inclined surface 326 is positioned so as to be able to abut against the tapered surface 346 of the cam 340. The inclined surface 326 has substantially the same inclination direction and inclination angle as the tapered surface 346. Here, "substantially equal" includes not only cases where the two are exactly the same, but also cases where they can be considered equal within the range of tolerances such as machining accuracy or assembly error (for example, within a range of 3% or less). The same applies in the following description. The inclined surface 326 may be a curved inclined surface having an inclination corresponding to the tapered surface 346 of the cam 340. Alternatively, the inclined surface 326 may be a planar inclined surface having an inclination corresponding to the tapered surface 346 of the cam 340.

[0028] The coil spring 350 is provided around the rod 330. The rod 330 is provided with a first stopper 362 and a second stopper 364, and the cam 340 and the coil spring 350 are provided between the first stopper 362 and the second stopper 364. The first stopper 362 restricts the movement of the cam 340 and the coil spring 350 in the +X direction. The second stopper 364 restricts the movement of the cam 340 and the coil spring 350 in the -X direction.

[0029] One end of the coil spring 350 abuts against the cam 340, and the other end of the coil spring 350 abuts against the second stopper 364. Here, one end of the coil spring 350 is housed in a recess 348 of the cam 340. The coil spring 350 compresses when a load greater than a predetermined force is applied to the cam 340 in the -X direction, allowing the cam 340 to move in the -X direction. The coil spring 350 also extends when a load less than a predetermined force is applied to the cam 340 in the -X direction, biasing the cam 340 in the +X direction. Here, the predetermined force is, for example, the biasing force of the coil spring 350.

[0030] Next, the operation of the shift device 100, the drive mechanism 200, and the parking device 300 will be described in detail. When the vehicle 1 is stopped or parked, the driver operates the shift lever 110 of the shift device 100 in the +X direction, for example, from the D range 150 to the P range 120.

[0031] At this time, the operating force of the shift lever 110 moving in the +X direction is transmitted to the rod 330 of the parking device 300 via the drive mechanism 200, and the rod 330 moves in the +X direction. In the first embodiment, the drive mechanism 200 is a rod-shaped connecting member that connects the shift lever 110 and the rod 330. However, it is not limited to this, and the drive mechanism 200 may be equipped with an actuator, and the rod 330 may be configured to be driven by the actuator. Specifically, when the shift position sensor of the shift device 100 detects that the shift lever 110 has been operated to the P range, the rod 330 may be configured to be driven in the +X direction by the actuator. Alternatively, when the shift position sensor detects that the shift lever 110 has been operated to a range other than the P range, the rod 330 may be configured to be driven in the -X direction by the actuator.

[0032] When the rod 330 is driven in the +X direction, the cam 340 and coil spring 350, whose movement is restricted by the second stopper 364, move together with the rod 330 in the +X direction.

[0033] Figure 5 is an XZ cross-sectional view of the parking device 300 in the state where the rod 330 shown in Figure 4 has moved in the +X direction. As shown in Figure 5, the tapered surface 346 of the cam 340 also moves in the +X direction in accordance with the movement of the rod 330 in the +X direction. Then, the tapered surface 346 of the cam 340 comes into contact with the inclined surface 326 of the parking pole 320 and presses the inclined surface 326 in the +Z direction perpendicular to the +X direction. Here, the inclined surface 326 of the parking pole 320 is the pressed surface that is pressed by the tapered surface 346 of the cam 340. Also, the tapered surface 346 of the cam 340 is the pressing surface that presses against the inclined surface 326 of the parking pole 320.

[0034] Figure 6 is a schematic diagram showing the configuration of the parking device 300 when the parking pawl 320 shown in Figure 3 is pressed in the +Z direction. As shown in Figure 6, when the parking pawl 320 is pressed in the +Z direction, the parking pawl 320 rotates around the central axis of the shaft 322 in a direction toward the parking gear 310 (for example, clockwise in Figure 6), against the biasing force of a coil spring (not shown). At this time, the projection 324 of the parking pawl 320 enters between the multiple teeth 314 of the parking gear 310 and engages with one of the teeth 314. As a result, the parking pawl 320 is positioned in a first position where the multiple teeth 314 of the parking gear 310 and the projection 324 of the parking pawl 320 mesh.

[0035] When the parking pole 320 is positioned in the first position, the multiple teeth 314 of the parking gear 310 are restricted from moving in the clockwise and counterclockwise directions, which are the rotational directions of the parking gear 310. This restricts the rotation of the power transmission shaft 312, which rotates integrally with the parking gear 310, and as a result, restricts the rotation of the wheels of the vehicle 1. Therefore, it is possible to prevent the vehicle 1 from moving unintentionally when it is stopped or parked.

[0036] When starting vehicle 1 from a standstill or parking position, the driver operates the shift lever 110 of the shift device 100 in the -X direction, for example, from the P range 120 to the D range 150. At this time, the operating force of the shift lever 110 moving in the -X direction is transmitted to the rod 330 of the parking device 300 via the drive mechanism 200, and the rod 330, cam 340, and coil spring 350 move in the -X direction.

[0037] As described above, the parking pawl 320 is biased by a coil spring (not shown) in a direction that brings it closer to the rod 330 and the cam 340. Therefore, as shown in Figure 4 compared to Figure 5, the parking pawl 320 moves in the -Z direction as the tapered surface 346 of the cam 340 moves in the -X direction due to the biasing force of the coil spring. At this time, as shown in Figure 3 compared to Figure 6, the parking pawl 320 rotates around the central axis of the shaft 322 in a direction that moves it away from the parking gear 310 (for example, counterclockwise in Figure 3).

[0038] As the parking pawl 320 rotates counterclockwise, the projection 324 of the parking pawl 320 disengages from the multiple teeth 314 of the parking gear 310, as shown in Figure 3. As a result, the parking pawl 320 is positioned in a second position where the engagement between the multiple teeth 314 of the parking gear 310 and the projection 324 of the parking pawl 320 is released.

[0039] When the parking pole 320 is positioned in the second position, the multiple teeth 314 of the parking gear 310 can move freely in the clockwise and counterclockwise directions, which are the rotational directions of the parking gear 310. This allows the power transmission shaft 312 and the wheels of the vehicle 1 to rotate, making it possible to move the vehicle 1.

[0040] Incidentally, when the parking pawl 320 is moved from the non-engaged position (second position) to the engaged position (first position), the parking gear 310 and the parking pawl 320 may lock in a loosely engaged state. In that case, normally, in response to the movement of the rod 330 in the +X direction, the cam 340 compresses the coil spring 350 and moves relative to the rod 330 in the axial direction (X direction). As a result, even if the rod 330 moves further in the +X direction, the movement of the cam 340 in the +X direction can be suppressed, and as a result, further movement of the parking pawl 320 to the first position due to the movement of the cam 340 in the +X direction can be prevented.

[0041] However, if the coefficient of friction increases locally at the contact surface between the inner surface of the cam 340 and the outer surface of the rod 330, or if a snag occurs, the cam 340 may become unable to move relative to the rod 330. In that case, the cam 340 moves the parking pawl 320 further to the first position, while the movement of the parking pawl 320 is restricted by the teeth 314 of the parking gear 310, which may cause the parking pawl 320 to break.

[0042] Figure 7 is an XZ cross-sectional view of the cam 340 according to the first embodiment. In Figure 7, the external shape of the cam 340 is shown in a simplified manner for the sake of simplicity. In Figure 7, R1 is the initial contact region, G is the center of gravity of the cam 340, L1 is a line indicating the position of the center of gravity G in the X direction, P is the load applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340, and L2 is a line indicating the center position of the load P in the X direction. Here, the initial contact region R1 is defined as a part of the tapered surface 346 of the cam 340 that contacts the inclined surface 326 of the parking pole 320 when the cam 340 begins to contact the parking pole 320 due to the axial movement of the rod 330. In the example shown in Figure 7, the initial contact region R1 is a part of the tapered surface 346 of the cam 340 in the axial direction. However, it is not limited to this, and the initial contact region R1 may be the entire tapered surface 346 of the cam 340 in the axial direction.

[0043] As shown in Figure 7, the axial (X-direction) position of the center of gravity G of the cam 340 is located within the initial contact region R1. Also, the center position L2 of the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340 in the axial direction is located in the center within the initial contact region R1. In the first embodiment, the axial position of the tapered surface 346 is adjusted and set so that the center of gravity G of the cam 340 in the axial direction is located within the initial contact region R1.

[0044] Furthermore, in the first embodiment, the axial (X-direction) position of the center of gravity G of the cam 340 in the axial direction is located at a position corresponding to the center position L2 of the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340. The position corresponding to the center position L2 of the load P is, for example, a position within the range on the side of the center position L2 relative to an intermediate position between the center position L2 in the axial direction and one end of the initial contact area R1 on the +X direction side.

[0045] In Figure 7, for the sake of clarity and ease of understanding, the axial position of the center of gravity G, shown by a dashed line, and the center position L2, shown by a dashed line, are shown shifted in the X direction. In the first embodiment, the position of the center of gravity G of the cam 340 in the X direction substantially coincides with the center position L2 of the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340. Here, "substantially coincides" includes not only cases where the two are perfectly coincided, but also cases where they can be considered to coincide within the range of tolerances such as machining accuracy or assembly error (for example, within a range of 3% or less). The same applies in the following explanation. A position that substantially coincides with the center position L2 is, for example, a position where the length between the center of gravity G and the center position L2 in the axial direction is 3% or less of the total length of the initial contact area R1 in the axial direction.

[0046] As the position of the center of gravity G in the axial direction approaches the center position L2, i.e., as they coincide, the load P applied from the inclined surface 326 of the parking pawl 320 to the tapered surface 346 of the cam 340 acts uniformly across the entire contact surface between the inner surface of the cam 340 and the outer surface of the rod 330. Therefore, when the position of the center of gravity G in the axial direction is closer to the center position L2 than when it is farther away, the local coefficient of friction at the contact surface between the inner surface of the cam 340 and the outer surface of the rod 330 is less likely to increase, or sticking is less likely to occur. Thus, when the parking gear 310 and the parking pawl 320 are locked in a shallow engagement state, the cam 340 can compress the coil spring 350 and move relative to the rod 330 in accordance with the movement of the rod 330 in the +X direction. Because the cam 340 can move relative to the rod 330, it is possible to suppress the parking pawl 320 from locking in a shallow engagement state. As a result, even if the rod 330 moves further in the +X direction, the movement of the cam 340 in the +X direction can be suppressed, and as a result, further movement of the parking pole 320 to the first position due to the movement of the cam 340 in the +X direction can be prevented, thereby suppressing damage to the parking pole 320.

[0047] Furthermore, the inclined surface 326 of the parking pole 320 may be an inclined surface with a curved shape having an inclination corresponding to the tapered surface 346 of the cam 340. For example, the shape of the inclined surface 326 of the parking pole 320 may be the same as the shape of the contact portion of the tapered surface 346 of the cam 340 that contacts the inclined surface 326. In that case, the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340 can be widely distributed, and as a result, the increase in the local coefficient of friction and the occurrence of snagging at the contact surface between the inner surface of the cam 340 and the outer surface of the rod 330 can be further reduced.

[0048] Figure 8 is an XZ cross-sectional view of the cam 1340 according to the second embodiment. In the second embodiment, components that are substantially the same as those in the vehicle 1 of the first embodiment are denoted by the same reference numerals and their descriptions are omitted. In Figure 8, the external shape of the cam 1340 is shown in a simplified manner for the sake of simplicity.

[0049] As shown in Figure 8, the position of the center of gravity G of the cam 340 in the axial direction is located within the initial contact region R1. Also, the center position L2 of the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340 in the axial direction is located in the center within the initial contact region R1. In the second embodiment, the recessed portion 348 that was provided on the -X direction side of the cam 340 in the first embodiment is filled in to make it a solid portion. As a result, the position of the center of gravity G of the cam 340 in the axial direction shifts to the -X direction side, and as a result, the center of gravity G is located within the initial contact region R1. In the second embodiment, unlike the first embodiment, the position of the center of gravity G of the cam 340 in the X direction does not substantially coincide with the center position L2 of the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340, and is offset.

[0050] As the position of the center of gravity G in the axial direction approaches the center position L2, the load P applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 340 acts uniformly across the entire contact surface between the inner surface of the cam 340 and the outer surface of the rod 330.

[0051] When the center of gravity G of the cam 340 in the axial direction is located within the initial contact region R1, rather than outside the region R1, the local coefficient of friction and jamming at the contact surface between the inner surface of the cam 340 and the outer surface of the rod 330 are less likely to increase. Therefore, when the parking gear 310 and the parking pawl 320 are locked in a shallow engagement state, the cam 340 can compress the coil spring 350 and move relative to the rod 330 in response to the movement of the rod 330 in the +X direction. Because the cam 340 can move relative to the rod 330, it is possible to suppress the parking pawl 320 from locking in a shallow engagement state. As a result, even if the rod 330 moves further in the +X direction, the movement of the cam 340 in the +X direction is suppressed, and as a result, further movement of the parking pawl 320 to the first position due to the movement of the cam 340 in the +X direction can be prevented, and damage to the parking pawl 320 can be suppressed. In the second embodiment, the position of the center of gravity G of the cam 340 in the axial direction is set to be within the initial contact region R1 by solidly filling the recess 348. However, the embodiment is not limited to this, and for example, the position of the center of gravity G of the cam 340 in the axial direction may be set to be within the initial contact region R1 by reducing the volume of the cylindrical portion 342 of the cam 340.

[0052] Figure 9 is an XZ cross-sectional view of the cam 2340 according to the third embodiment. In the third embodiment, components that are substantially the same as those in the vehicle 1 of the first embodiment are denoted by the same reference numerals and their descriptions are omitted. In the third embodiment, the shape of the through hole 2340a of the cam 2340 differs from that of the first embodiment.

[0053] As shown in Figure 9, the cam 2340 of the third embodiment has a through hole 2340a through which the rod 330 is inserted in the axial direction. The inner diameter of the through hole 2340a gradually increases from the axial center to both ends. When cut with an XZ cross section parallel to the axial direction, the cross-sectional shape of the through hole 2340a is a curved shape in which the inner diameter gradually increases from the axial center to both ends. Specifically, the cross-sectional shape of the through hole 2340a when cut with an XZ cross section parallel to the axial direction is a crowning shape. In the crowning shape, the rate of change of the inner diameter of the through hole 2340a gradually increases from the axial center to both ends.

[0054] As a result, the distance between the inner surface of the through-hole 2340a of the cam 2340 and the outer surface of the rod 330 gradually increases from the axial center of the cam 2340 to both ends. The cross-sectional shape of the through-hole 2340a when cut along an XZ cross-section parallel to the axial direction may be a V-shaped tapered shape in which the inner diameter gradually increases from the axial center of the through-hole 2340a to both ends. In other words, the rate of change in the inner diameter from the axial center of the through-hole 2340a to both ends may be constant.

[0055] The gap between the through-hole 2340a at both ends of the cam 2340 and the rod 330 is larger than the gap between the through-hole 2340a at the axial center of the cam 2340 and the rod 330. Therefore, when a load P is applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 2340, the cam 2340 can rotate slightly around the Y axis. In addition, the XZ cross-sectional shape of the through-hole 2340a is a gently curved shape. When a load P is applied from the inclined surface 326 of the parking pole 320 to the tapered surface 346 of the cam 2340, the cam 340 rotates slightly, and the inner circumferential surface of the through-hole 2340a of the cam 2340 and the outer circumferential surface of the rod 330 come into smooth contact. This makes it less likely for the coefficient of friction to increase locally or for snagging to occur at the contact surface between the inner surface of the through-hole 2340a of the cam 2340 and the outer surface of the rod 330. Therefore, when the parking gear 310 and the parking pawl 320 are locked in a shallow engagement state, the cam 2340 can compress the coil spring 350 and move relative to the rod 330 in response to the movement of the rod 330 in the +X direction. Because the cam 2340 can move relative to the rod 330, it is possible to suppress the parking pawl 320 from locking in a shallow engagement state. As a result, even if the rod 330 moves further in the +X direction, the movement of the cam 2340 in the +X direction is suppressed, and as a result, further movement of the parking pawl 320 to the first position due to the movement of the cam 2340 in the +X direction can be prevented, and damage to the parking pawl 320 can be suppressed.

[0056] Embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention. [Explanation of Symbols]

[0057] G center of gravity P load L2 center position R1 First hit area 310 Parking gear 320 Parking Pole 326 Inclined surface (pressed surface) 330 Rod 340, 1340, 2340 cams 346 Tapered surface 340a, 2340a through hole

Claims

1. Parking gear and, A parking pawl is mounted on the first drive shaft and is configured to be rotatable between a first position in which it engages with the parking gear and a second position in which it is disengaged from the parking gear. A rod configured to be movable in the axial direction, A cam having a tapered surface is attached to the rod and rotates the parking pole from the second position to the first position by pressing a pressed surface formed on the parking pole in a direction perpendicular to the axial direction in accordance with the axial movement of the rod, Equipped with, When the cam begins to contact the parking pole due to the axial movement of the rod, if a portion of the tapered surface of the cam that contacts the pressed surface of the parking pole is defined as the initial contact area, then the center of gravity of the cam in the axial direction is located within the initial contact area. vehicle.

2. The center of gravity of the cam in the axial direction is positioned at a location corresponding to the center of the load applied from the pressed surface of the parking pole to the tapered surface of the cam. The vehicle according to claim 1.

3. The cam has a through hole through which the rod is inserted in the axial direction, The inner diameter of the through hole gradually increases from the axial center of the through hole to both ends. The vehicle according to claim 1 or 2.

4. When the through-hole is cut along a cross-section parallel to the axial direction, the cross-sectional shape of the through-hole is a curved shape that gradually widens from the center to both ends in the axial direction. The vehicle according to claim 3.

5. The pressed surface of the parking pole is an inclined surface having an inclination corresponding to the tapered surface of the cam. The vehicle according to claim 1.

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