Transmission

The present invention relates to a transmission provided with a parking mechanism for holding a stopped state of a vehicle.

Some transmissions that shift the rotation output by a drive source such as an engine include a parking mechanism that holds a stopped state when the vehicle stops. For example, Patent Document 1 discloses a parking mechanism that regulates the rotation of an output shaft by engaging a claw portion of a parking pole with a parking gear fixed to the output shaft of a transmission. Such a parking mechanism needs to separate the parking pole from the parking gear in order to bring it into an unlocked state that does not restrict the rotation of the output shaft. Therefore, in the parking mechanism of Patent Document 1, a torsion spring is arranged on the outer periphery of a support shaft that rotatably supports the parking pole, and the parking pole is urged in the release direction by the elastic force thereof.

However, in such a configuration, the urging position of the parking pole by the torsion spring is relatively close to the rotation axis of the parking pole, so that the torsion spring requires a strong elastic force. Then, when assembling the parking mechanism, the load for resisting the torsion spring becomes large, and there is a concern that the assembling property may be deteriorated. Further, as the elastic force increases, the diameter of the torsion spring may increase, and the size of the parking mechanism as a whole may increase. Therefore, for example, Patent Document 2 discloses a parking mechanism in which a torsion spring is supported by pins arranged apart from the rotation axis of the parking pole. According to this, since the position where the torsion spring urges the parking pole is separated from the rotation axis of the parking pole, it is considered that a torsion spring having a relatively low elastic force can be applied.

<p num="0004"><patcit num="1"><text>JP-A-2007-326438</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2011-020469</text></patcit></p>

<p num="0005"> By the way, there is a demand for a smaller transmission for the purpose of improving the mountability on a vehicle. Therefore, the parking mechanism of the transmission may be restricted in the position and dimensions arranged inside the transmission. Due to such restrictions, when the claw portion of the parking pole is arranged so as to be located above the parking gear as in the parking mechanism of Patent Document 2, the weight of the parking pole affects the operation of the parking mechanism. I have something to do. Then, in order to operate the parking mechanism properly, it becomes necessary to increase the elastic force of the torsion spring. Then, as described above, there are concerns about a decrease in assembling property and an increase in the size of the parking mechanism.</p><p num="0006"> The present invention has been made in view of the above problems, and an object of the present invention is to provide a transmission provided with a parking mechanism capable of miniaturization while ensuring more stable operation.</p>

<p num="0007"> In order to solve the above-mentioned problems, according to the invention of claim 1, the case, the drive shaft rotatably supported by the case, the parking gear fixed to the drive shaft, and the case rotatable. Rotates between a locking position that is supported by the parking gear and restricts the rotation of the drive shaft and a unlocking position that disengages from the parking gear and allows the drive shaft to rotate. The locking member, the support member provided in the case away from the rotation axis of the locking member, and the locking member in the direction in which the locking member rotates from the locking position to the unlocking position. A pair of urging members that urge the members and are supported by the supporting members at symmetrical positions on both sides of the locking member in the rotation axis direction with reference to the locking member. ..</p><p num="0008"> According to the second aspect of the present invention, in the first aspect, the support member is supported by an arm portion provided on the inner peripheral side of the case at a portion located between the pair of the urging members. ..</p><p num="0009"> According to the third aspect of the present invention, in the second aspect, the urging member is a torsion spring having a coil portion, and the support member inserts the inner peripheral side of the coil portion into a pair of the urging members. It has a shaft-shaped portion that supports the member coaxially.</p><p num="0010"> According to the invention of claim 4, in claim 3, the arm portion is provided on the outer peripheral side of the shaft-shaped portion, and the support member is supported by the arm portion of the case on one side in the rotation axis direction of the arm portion. It has a restricting member that abuts on the end face of the support member and restricts the movement of the support member to the other side in the rotation axis direction, and an annular flange portion formed at the end portion of the shaft-shaped portion on the other side in the rotation axis direction. ..</p><p num="0011"> According to the invention of claim 5, in any one of claims 1 to 4, the pair of the urging members are set to have the same elastic force as each other.</p><p num="0012"> According to the invention of claim 6, in any one of claims 1 to 5, a lid that covers the opening of the case and supports the end of the support member on any one side in the rotation axis direction. Further members may be provided.</p>

<p num="0013"> According to the invention of claim 1, the pair of urging members are supported by the support members at symmetrical positions on both sides of the locking member in the rotation axis direction with reference to the locking member. Thereby, the pair of urging members can be set to have the required elastic force as a whole. Then, each urging member can set the individual elastic force low. Therefore, the urging member has an elastic force required for the operation of the parking mechanism, and has a configuration in which a single urging member covers the required elastic force as in the conventional case, or a configuration in which the urging members are arranged in parallel at a plurality of locations. In comparison with the above, the size of the drive shaft can be reduced in the radial direction. Further, when assembling the parking mechanism, a pair of urging members can be individually arranged, so that the load required for each assembling is reduced and the assembling property can be improved.</p><p num="0014"> According to the invention of claim 2, the support member has a portion located between the pair of urging members supported by the arm portion of the case. In the conventional parking mechanism, the support member that supports the urging member has a configuration in which both ends thereof are supported by a case, for example. Therefore, in the case, it is necessary to form a boss or the like at a portion where both ends of the support member are located. On the other hand, in the present invention, with the above configuration, the position used as a reference when arranging the pair of urging members and the position where the support member is supported by the case coincide with each other in the rotation axis direction. become. As a result, the support member can be reliably supported without supporting both ends by bosses or the like. Therefore, it is not necessary to form a boss or the like as in the conventional case, and space can be further saved.</p><p num="0015"> According to the invention of claim 3, a pair of urging members, which are torsion springs, are coaxially supported by a shaft-shaped portion of the support member. As a result, the locking member comes into contact with one end of each pair of torsion springs and is urged in a direction of rotationally moving from the locking position to the unlocking position. Since the coil portions of such torsion springs are arranged coaxially, the parking mechanism can be more reliably miniaturized as compared with a configuration in which a plurality of urging members are arranged in parallel.</p><p num="0016"> According to the invention of claim 4, the support member is restricted from moving to the other side in the rotation axis direction by the regulating member. The support member has a collar formed at the end of the shaft-shaped portion. That is, one of the pair of urging members is interposed between the arm portion and the flange portion of the case. The other of the pair of urging members is interposed between the end of the shaft-shaped portion on one side in the rotation axis direction and the regulating member. As a result, the pair of urging members can urge the locking member in a well-balanced manner, so that the operation can be made more stable. Further, since the arm portion can always support the portion located between the pair of urging members, the support member can be provided in the case more stably.</p><p num="0017"> According to the invention of claim 5, the pair of urging members are set to have equal elastic forces. Here, the pair of urging members are arranged at symmetrical positions on both sides of the locking member in the rotation axis direction with reference to the locking member. Therefore, if the elastic forces of the respective urging members are set to be equal as described above, the maximum size of each urging member can be reduced in order to obtain the total elastic force required by the parking mechanism. It is possible to reduce the size as a whole. Further, since the locking member can be urged in a well-balanced manner by the pair of urging members, the operation can be more stable.</p><p num="0018"> According to the invention of claim 6, the support member is supported by a lid member that covers the opening of the case at one end of the locking member on one side in the rotation axis direction. The support member is provided so as to be supported by the case, but the end portion on one side thereof can be more reliably fixed to the case by being supported by the lid member, for example, auxiliary. Therefore, since the support member can more reliably support the pair of urging members, the operation of the parking mechanism can be made more stable.</p>

<figref num="1">It is a block diagram which shows a part of the gears seen from the axial direction of the transmission 1 in embodiment.</figref><figref num="2">It is an enlarged view of FIG. 1 which shows the parking mechanism.</figref><figref num="3">It is the A direction arrow view in FIG.</figref>

Hereinafter, embodiments embodying the transmission of the present invention will be described with reference to the drawings.

&lt;Embodiment&gt; (Configuration of transmission 1) The configuration of the transmission 1 in the present embodiment will be described with reference to FIGS. 1 to 3. The transmission 1 is a mechanical transmission mounted on a vehicle, and constitutes a forward or reverse transmission stage by a plurality of transmission gears supported by a rotating shaft. As shown in FIG. 1, the transmission 1 includes a case 10, a rear retainer 12, an input shaft 20, an output shaft 30 (corresponding to the drive shaft of the present invention), a differential 40, and a parking mechanism 50. To be equipped.

The case 10 supports a rotating shaft by a plurality of bearings, and houses a plurality of gears and a parking mechanism 50 arranged on the rotating shaft. The case 10 has an arm portion 11 and a rear retainer 12. The arm portion 11 is provided on the inner peripheral side of the case 10 so as to extend toward the parking mechanism 50. As shown in FIG. 3, the arm portion 11 is formed with a through hole 11a penetrating in the rotation axis direction. The rear retainer 12 is a lid member that covers the opening of the case 10, and is bolted and fixed to the case 10. Further, the rear retainer 12 is formed with a cylindrical recess 12a extending in the axial direction of the rotation axis on the inner surface facing the inside of the transmission 1.

The input shaft 20 is a rotating shaft formed in a shaft shape and rotatably supported by a bearing on the case 10. The input shaft 20 is connected to an engine, which is a drive source of the vehicle, via a clutch mechanism (not shown), and a driving force is input. Further, as shown in FIG. 1, the input shaft 20 supports a transmission gear on the input side including the input gear 21 among the gear pairs constituting the plurality of transmission stages. The input gear 21 is press-fitted into an external tooth spline formed on the outer peripheral surface of the input shaft 20 and meshes with a transmission gear on the output side supported by the output shaft 30 to form a predetermined speed change stage.

The output shaft 30 is a rotating shaft formed in a shaft shape and rotatably supported by a bearing on the case 10. As shown in FIG. 1, the output shaft 30 supports a transmission gear on the output side including the output gear 31 among the gear pairs constituting the plurality of transmission stages. Then, the output shaft 30 outputs the driving force shifted by the predetermined shift stage via the differential 40. The output gear 31 is supported so as to be rotatable relative to the output shaft 30, and meshes with a transmission gear on the input side supported by the input shaft 20. The output gear 31 is selectively connected to the output shaft 30 by a shift mechanism (not shown) to form a predetermined gear together with the transmission gear on the input side.

The differential 40 is a differential device in the vehicle. The differential 40 has a final drive gear 41 and a ring gear 42, as shown in FIG. The final drive gear 41 is press-fitted into an external tooth spline formed on the outer peripheral surface of the output shaft 30, and is connected and fixed to the output shaft 30. The ring gear 42 is rotatably supported with respect to the case 10, is connected to the drive wheels via a drive shaft (not shown), and is interlocked with the rotation of the drive wheels. Further, the ring gear 42 is in a state of being constantly meshed with the final drive gear 41 and rotationally connected to the output shaft 30.

The parking mechanism 50 regulates the rotation of the output shaft 30, which is the drive shaft, when the vehicle stops, thereby regulating the rotation of the drive wheels that are interlocked with the ring gear that is rotationally connected to the output shaft 30, and the vehicle is in a stopped state. It is a mechanism to hold. The parking mechanism 50 mainly includes a parking gear 51, a manual shaft 52, a manual valve lever 53, a rod 54, a cam 55, a cam spring 56, a parking pole 57, a pole support shaft 58, and a pair of torsions. It is composed of springs 61 and 62 and a spring support shaft 63.

A plurality of external teeth are formed on the outer peripheral surface of the parking gear 51, and the parking gear 51 is press-fitted into an external tooth spline formed on the outer peripheral surface of the output shaft 30 and fixed to the output shaft 30. As shown in FIG. 1, the manual shaft 52 is a shaft-shaped member extending in the vertical direction of the transmission 1 and is rotatably supported by the case 10. The manual shaft 52 is rotated around the central axis so as to have an angle corresponding to the shift position of the vehicle. The manual valve lever 53 is fixed at the lower part of the manual shaft 52 perpendicular to the central axis of the manual shaft 52. With such a configuration, the manual valve lever 53 rotates integrally in conjunction with the rotation of the manual shaft 52.

The rod 54 is a shaft-shaped member extending in a direction parallel to the drive shaft of the transmission 1 (front-rear direction in FIGS. 1 and 2 and left-right direction in FIG. 3), and one end thereof swings with respect to the manual valve lever 53. It is connected as possible. As a result, the rod 54 moves in the extending direction of the rod 54 as the connected manual valve lever 53 rotates. Further, as shown in FIG. 3, the rod 54 is formed with an annular stopper 54a protruding in the radial direction from the outer peripheral surface.

The cam 55 has a large diameter portion formed on one side in the axial direction of the rod 54 and a small diameter portion formed so that the outer diameter gradually decreases from the large diameter portion toward the other side in the axial direction. ing. Further, the cam 55 is formed with a cylindrical inner peripheral surface, and is slidably provided on a rod 54 through which the inner peripheral surface is inserted. The cam spring 56 is a coiled compression spring, and is interposed between the stopper 54a of the rod 54 and the cam 55 on the outer peripheral side of the rod 54. One end of the cam spring 56 is fixed to the stopper 54a, and the other end of the cam spring 56 is fixed to the cam 55. As a result, the cam 55 maintains a distance from the stopper 54a due to the free length of the cam spring 56 when the cam spring 56 is unloaded.

As shown in FIG. 2, the parking pole 57 is rotatably supported by the case 10 via a pole support shaft 58, and is formed so as to extend in the radial direction of the rotation shaft. Further, the axial position of the parking pole 57 is set to coincide with the axial position of the parking gear 51 in the case 10. The parking pole 57 projects toward the output shaft 30 on the outer peripheral surface of the central portion in the longitudinal direction, and a locking claw 57a that can be locked with the outer teeth formed on the outer peripheral surface of the parking gear 51 is formed.

When the parking pole 57 rotates to one side with the pole support shaft 58 as the rotation axis, the locking claw 57a locks on the parking gear 51 and moves to a locking position that regulates the rotation of the output shaft, which is the drive shaft. Further, when the parking pole 57 rotates to the other side with the pole support shaft 58 as the rotation axis, the locking claw 57a disengages from the parking gear 51 and moves to an unlocking position that allows the output shaft 30 to rotate. As described above, the parking pole 57 is a locking member that rotationally moves between the above-mentioned regulation position and the unlocking position as the pole support shaft 58 rotates around the rotation axis. The pole support shaft 58 is a shaft-shaped member supported by the case 10 and supports the parking pole 57 on the outer peripheral surface.

The pair of torsion springs 61, 62 are urging members having coil portions 61a, 62a formed therein and having elastic force in the circumferential direction of the coil portions 61a, 62b. In the present embodiment, the elastic forces of the torsion spring 61 and the torsion spring 62 are set to be equal to each other and to be the required elastic forces as a whole. Further, the torsion springs 61 and 62 are arranged so that one end abuts on the lower side (lower side in FIGS. 2 and 3) of the tip of the parking pole 57 and the other end is fixed to the case 10. There is. As a result, the pair of torsion springs 61 and 62 urge the parking pole 57 in the direction in which the parking pole 57 rotates and moves from the locked position to the unlocked position (upward in FIGS. 2 and 3).

Here, the parking pole 57 has a rear portion (upper portion in FIGS. 2 and 3) of the tip opposite to the position urged by the torsion springs 61 and 62 on the outer peripheral surface of the rod 54 or the cam 55. It is in contact. That is, when the back surface of the parking pole 57 is in contact with the small diameter portion of the outer peripheral surface of the rod 54 or the cam 55, the parking pole 57 is rotationally moved to the unlocked position by the elastic force of the torsion springs 61 and 62. become. Further, when the back surface portion of the parking pole 57 is in contact with the large diameter portion of the outer peripheral surface of the cam 55, the parking pole 57 rotates and moves to the locking position against the elastic force of the torsion springs 61 and 62. become.

The pair of torsion springs 61 and 62 are supported by the spring support shaft 63 at symmetrical positions on both sides of the parking pole 57 in the rotation axis direction (horizontal direction in FIG. 3) with reference to the parking pole 57. The spring support shaft 63 has a shaft-shaped portion 63a, an insertion portion 63b, a flange portion 63c, and a snap ring 63d. The shaft-shaped portion 63a is a cylindrical member extending in the drive shaft direction of the transmission 1. Further, as shown in FIG. 2, the spring support shaft 63 is a support member provided in the case 10 away from the rotation shaft of the parking pole 57 (the central shaft of the pole support shaft 58).

More specifically, as shown in FIG. 3, the spring support shaft 63 has a shaft-shaped portion 63a inserted through a through hole 11a of the arm portion 11 provided on the inner peripheral side of the case 10. As a result, the spring support shaft 63 is supported by the arm portion 11 of the case 10 at a portion located between the pair of torsion springs 61 and 62. The spring support shaft 63 is formed so as to have a substantially symmetrical shape in the rotation axis direction with respect to the parking pole 57 as an overall shape. Therefore, in the present embodiment, the spring support shaft 63 is supported by the case 10 at the central portion in the axial direction.

Further, the shaft-shaped portion 63a of the spring support shaft 63 inserts the coil portion 61a of the torsion spring 61 and the inner peripheral side of the coil portion 62b of the torsion spring 62 to coaxially support the torsion springs 61 and 62. .. Further, the insertion portion 63b of the spring support shaft 63 is a portion formed at an end portion on one side (left side in FIG. 3) of the shaft-shaped portion 63a. The insertion portion 63b is set to an outer diameter slightly smaller than the inner diameter of the recess 12a formed on the inner surface of the rear retainer 12, and is inserted into the recess 12a. Thereby, the rear retainer 12 supports one end of the spring support shaft 63.

The flange portion 63c of the spring support shaft 63 is an annular portion formed at the other end (right side in FIG. 3) of the shaft-shaped portion 63a and projecting radially from the outer peripheral surface of the shaft-shaped portion 63a. The flange portion 63c prevents the torsion spring 62 supported by the shaft-shaped portion 63a from coming off. Further, the snap ring 63d of the spring support shaft 63 is a regulating member that is fitted into an annular groove formed on the outer peripheral surface near the axial center portion of the shaft-shaped portion 63a to regulate the axial movement of the spring support shaft 63. is there. More specifically, the snap ring 63d abuts on the end surface of the arm portion 11 on one side in the rotation axis direction (left side in FIG. 3) in a state where the spring support shaft 63 is supported by the arm portion 11 of the case 10. As a result, the movement of the spring support shaft 63 to the other side in the axial direction (right side in FIG. 3) is restricted.

With such a configuration, the torsion spring 62 arranged on the flange portion 63c side of the pair of torsion springs 61 and 62 is interposed between the arm portion 11 and the collar portion 63c of the case 10. Further, of the pair of torsion springs 61 and 62, the torsion spring 61 arranged on the rear retainer 12 side is interposed between the rear retainer 12 into which the insertion portion 63b is inserted and the snap ring 63d. As a result, the parking pole 57 is urged at a target portion in the rotation axis direction by each one end portion of the pair of torsion springs 61 and 62.

(Operation of parking mechanism 50 of transmission 1) The operation of the parking mechanism 50 having such a configuration will be described. As described above, the parking pole 57 is always urged by a pair of torsion springs 61 and 62 in a direction of rotational movement from the locking position to the unlocking position. Then, for example, when the shift of the vehicle is operated by the driver to the P range, the manual shaft 52 is rotated by a predetermined angle. Then, the manual valve lever 53 rotates, and the rod 54 interlocks with this to move to one side in the axial direction. Then, due to the axial movement of the rod 54, the cam 55 is in a state of pressing the back surface portion of the parking pole 57. At this time, when the parking gear 51 is in a phase that can be locked with the locking claw 57a, the parking pole 57 rotates and moves to the locking position against the elastic force of the torsion springs 61 and 62, and the parking gear 51 Regulate the rotation of. As a result, the parking mechanism 50 is locked.

When the parking gear 51 is in a phase in which it cannot be locked with the locking claw 57a, the locking claw 57a is in contact with the tooth tip surface of the external tooth of the parking gear 51. Then, the stopper 54a of the rod 54 comes close to the cam 55, and the cam spring 56 is compressed. Subsequently, when a front-rear force is applied to the vehicle due to the influence of an inclined surface or the like, the drive wheels rotate, and the parking gear 51 rotates to a phase in which it can be locked with the locking claw 57a. Then, the cam 55 urged by the cam spring 56 presses the back portion of the parking pole 57, and the parking pole 57 rotates and moves to the locked position. In this way, the parking mechanism 50 is in a locked state that regulates the rotation of the drive shaft by locking the locking claw 57a of the parking pole 57 to the parking gear 51, and maintains the stopped state of the vehicle.

After that, when the shift of the vehicle is operated from the P range to another range, the manual shaft 52 is rotated in the opposite direction by a predetermined angle. Then, the manual valve lever 53 rotates, and the rod 54 interlocks with the rotation to move to the other side in the axial direction. Then, due to the axial movement of the rod 54, the cam 55 does not press the back surface of the parking pole 57. Then, the elastic force of the torsion springs 61 and 62 causes the parking pole 57 to rotate and move to the unlocked position, and the parking mechanism 50 is in an unlocked state that allows the parking gear 51 and the drive shaft to rotate.

(Effect of transmission 1) According to the transmission 1 provided with the parking mechanism 50 having the above-described configuration, the following effects are obtained. In the present embodiment, the pair of torsion springs 61 and 62 are supported by the spring support shaft 63 at symmetrical positions on both sides of the parking pole 57 in the rotation axis direction with respect to the parking pole 57. As a result, the pair of torsion springs 61 and 62 can be set to have the required elastic force as a whole. Then, each torsion spring 61, 62 can set the individual elastic force low. Therefore, while the torsion springs 61 and 62 have the elastic force required for the operation of the parking mechanism 50, the torsion springs 61 and 62 are configured to cover the elastic force required by a single urging member as in the conventional case, or the urging members are arranged in parallel at a plurality of locations. Compared with the arrangement of the arrangement, the size of the drive shaft in the transmission 1 can be reduced in the radial direction.

Further, when the parking mechanism 50 is assembled, the pair of torsion springs 61 and 62 can be individually arranged, so that the load required for each assembly is reduced and the assembling property can be improved. Further, the spring support shaft 63 that supports the pair of torsion springs 61 and 62 is provided apart from the rotation axis of the parking pole 57. As a result, the positions where the torsion springs 61 and 62 urge the parking pole 57 can be set to positions separated from the rotation axis of the parking pole 57, so that a relatively low elastic force can be set.

Further, in the present embodiment, the spring support shaft 63 is configured to be supported by the arm portion 11 of the case 10 at a portion located between the pair of torsion springs 61 and 62. Here, in the conventional parking mechanism, in the configuration in which both ends of the support member supporting the urging member are supported by the case, it is necessary to form a boss or the like at a portion where both ends of the support member are located. On the other hand, in the present invention, according to the above configuration, the position used as a reference when arranging the pair of torsion springs 61 and 62 and the position where the spring support shaft 63 is supported by the case 10 are the rotation axes. It will match in the direction. As a result, the spring support shaft 63 can be reliably supported without supporting both ends by bosses or the like. Therefore, it is not necessary to form a boss or the like as in the conventional case, and space can be further saved.

Further, the parking mechanism 50 has a structure in which a pair of urging members are torsion springs 61, 62, and the coil portions 61a, 62a are coaxially supported by the shaft-shaped portion 63a of the spring support shaft 63. As a result, the parking mechanism 50 can be more reliably miniaturized as compared with the conventional configuration in which a plurality of urging members are arranged in parallel.

Further, the spring support shaft 63 has a flange portion 63c and a snap ring 63d. That is, the pair of torsion springs 61 and 62 are arranged so as to sandwich the arm portion 11, and are interposed between the arm portion 11 and the rear retainer 12, or between the arm portion 11 and the flange portion 63c. As a result, the pair of torsion springs 61 and 62 can urge the parking pole 57 in a well-balanced manner, so that the operation can be made more stable. Further, since the arm portion 11 can always support the portion located between the torsion springs 61 and 62, the spring support shaft 63 can be provided in the case 10 more stably.

Further, the pair of torsion springs 61 and 62 are arranged at symmetrical positions on both sides of the parking pole 57 in the rotation axis direction with respect to the parking pole 57, and are set to have elastic forces equal to each other. As a result, the pair of torsion springs 61 and 62 can be individually reduced in maximum size in order to obtain the total elastic force required by the parking mechanism 50, so that the overall size can be reduced. Further, the pair of torsion springs 61 and 62 can urge the parking pole 57 in a well-balanced manner, so that the operation can be stabilized.

Further, the spring support shaft 63 is supported by inserting an insertion portion 63b formed at one end of the parking pole 57 on one side in the rotation axis direction into the recess 12a of the rear retainer 12. The spring support shaft 63 is provided so as to be supported by the case 10, but one end thereof is supplementarily supported by the rear retainer 12 so that the spring support shaft 63 can be more securely fixed to the case 10. .. Therefore, since the spring support shaft 63 can more reliably support the pair of torsion springs 61 and 62, the operation of the parking mechanism 50 can be made more stable.

&lt;Modification of the embodiment&gt; In the present embodiment, the pair of urging members are torsion springs 61, 62 having coil portions 61a, 62a. On the other hand, if the parking pole 57, which is a locking member, is urged to rotate and move from the locking position to the unlocking position with elastic force, for example, a coil spring or a leaf spring is applied. May be good. Further, the pair of torsion springs 61 and 62 are set so that their elastic forces are equal to each other. On the other hand, for example, the elastic force may be set to be unequal in consideration of the limitation of the space in which the parking mechanism 50 can be arranged inside the case 10.

Further, the parking gear 51 of the parking mechanism 50 is fixed to the output shaft 30 as a drive shaft. On the other hand, it may be fixed to another rotating shaft, for example, the input shaft 20. Further, even in the case of the dual clutch type in which the transmission selectively switches between a plurality of input shafts and a plurality of output shafts to shift gears, the parking gear 51 may be provided on any of the rotating shafts. However, regardless of the configuration in which the parking gear 51 is provided on any of the rotating shafts, when the shift of the vehicle is operated to the P range, the rotating shaft to which the parking gear 51 is fixed is rotationally connected so as to be interlocked with the rotation of the drive wheels. Must have been. Even in such a configuration, the same effect as that of the embodiment is obtained.

1: Transmission, 10: Case, 11: Arm, 11a: Through hole 12: Rear retainer (lid member), 12a: Recess 20: Input shaft, 21: Input gear 30: Output shaft (drive shaft), 31: Output gear 40: Differential, 41: Final drive gear, 42: Ring gear 50: Parking mechanism, 51: Parking gear, 52: Manual shaft 53: Manual valve lever, 54: Rod, 54a: Stopper, 55: Cam 56: Cam spring, 57: Parking pole (locking member), 57a: Locking claw 58: Pole support shaft 61,62: Torsion spring (biasing member), 61a, 62a: Coil part 63: Spring support shaft (support member), 63a: Shaft-shaped part, 63b: Insert part 63c: collar, 63d: snap ring (regulatory member)