JP4570133B2 - Selective return device for transmission - Google Patents

Description

  The present invention relates to a select return device for returning a shift and select lever of a transmission to a neutral position when the shift and select lever is rotated in a select direction from a neutral position.

  For a manual transmission such as an automobile, as disclosed in, for example, Japanese Patent Laid-Open No. 2000-291790 (Patent Document 1), a lever housing provided with a shift-and-select lever by swinging the shift lever in the select direction is rotated. Select one of a plurality of fork shafts by moving, reciprocate the selected fork shaft by swinging the shift lever in the shift direction and reciprocating the lever housing in the axial direction to switch the transmission gear There is something to do.

  5 and 6 show an example of such a conventional manual transmission. In this manual transmission, a lever housing 3 fixed to a shift-and-select shaft 2 supported rotatably and reciprocally movable on a transmission casing 1 is provided with a small spherical portion 15a at the tip of a shift lever 15 via a sliding body 4. And a shift-and-select lever 3a that is selectively engaged with shift pieces (not shown) of a plurality of fork shafts. The shift lever 15 is supported by a shift tower 1a fixed to the casing 1 via a spherical seat 17 so that a hemispherical support 16 fixed to an intermediate portion of the shift lever 15 can swing freely. A pair of rotation restricting pins 17a fixed to the shift tower 1a are inserted into the pair of notches 16a formed in 16, thereby preventing the shift lever 15 from rotating about the axis. Between the spring receiver 18a fixed in the opening portion of the shift tower 1a and the support portion 16, a spring 18 that elastically presses the support portion 16 against the spherical seat 17 is interposed, and the opening portion of the shift tower 1a is inserted. A dust-proof boot 19 is provided between the outer periphery of the lens and the shift lever 15.

  In this manual transmission, if the shift lever 15 is swung around the support portion 16 as shown by the arrow in FIG. 6, the lever housing 3 rotates in the select direction around the shift and select shaft 2 and shifts. The AND select lever 3a selects one of the shift pieces of the plurality of fork shafts. In this state, the shift lever 15 is swung around the support portion 16 as shown by the arrow in FIG. As shown in the figure, when the reciprocation is made in the shift direction, which is the axial direction, the selected fork shaft reciprocates and the transmission gear is switched.

  As shown in FIG. 4 (a), in the case of a shift pattern of 5 forward speeds and 1 reverse speed, the 3rd and 4th speed positions are the neutral positions in the select direction, and the 1st, 2nd speeds or 5th speeds from this neutral position. When the shift lever 15 is moved to the reverse position and the hand is released from the shift lever 15 without shifting, the shift lever 15 and the lever housing 3 return to the neutral position. A select return force F as shown in the arrow a) and FIG. 4B is required. In the prior art shown in FIGS. 5 and 6, the select return force F is applied by a pair of pressing pin assemblies 6.

  As shown mainly in FIG. 6, the pair of pressing pin assemblies 6 are provided so as to face the casing 1 on both sides of the socket portion 3 b of the lever housing 3. Each pressing pin assembly 6 includes a cylinder 6a, a pressing pin 6b, a spring 6c, and a retainer 6d, and is attached by screwing the cylinder 6a into a part of the casing 1 toward the socket portion 3b. The pressing pin 6b has a cylindrical shape with a closed tip, is slidably fitted into the cylinder 6a from the rear end opening, and is held by a spring 6c interposed between the retainer 6d and fixed to the rear end opening of the cylinder 6a. In the free state, the outward flange at the rear end abuts against the step on the inner surface of the cylinder 6a and is stopped in the free state. In a state where the cylinder 6a is screwed into the casing 1, the spherical tip is brought into contact with the socket portion 3b in the stopped state described above or slightly retracted therefrom. As a result, the lever housing 3 is biased to the 3rd and 4th speed position (neutral position in the select direction) in the free state, and if it is swung to the 1st or 2nd speed position or the 5th speed / reverse position, FIG. A select return force F as shown in FIG.

If the number of gears is increased to a shift pattern of 6 forwards and 1 reverse as shown in Fig. 3 (a), two select positions for 1st, 2nd and reverse are provided in the same rotational direction. At the time of reverse, the lever housing 3 is shifted to the reverse position beyond the 1st and 2nd speeds and then shifted. In addition, as shown in FIG. 3 (b), it is necessary to increase the rate of increase of the select return force F with the position of the 1st and 2nd speed as a boundary. For this purpose, a third press pin assembly that increases the select return force F by acting after the position of the 1st and 2nd speeds is provided in parallel with the 1st and 2nd speed and the reverse side push pin assembly. Alternatively, the pressure pin assembly for the first and second speeds and the reverse side has a pressure piston interposed between the pressure pin 6b and the retainer 6d, and the spring 6c is interposed between the pressure pin 6b and the pressure piston, and the pressure piston and the retainer. A second spring having a spring constant larger than that of the spring 6c is interposed between the springs 6c so that the spring constant increases when the position of the first and second speeds is exceeded.
JP 2000-291790 A (paragraphs [0002] to [0006], FIGS. 4 to 6)

  In the prior art described above, even if the lever housing 3 reciprocates in the axial direction of the shift and select shaft 2 as indicated by the arrow in FIG. 5, the pressing pin assembly 6 does not come off from the socket portion 3 b of the lever housing 3. Therefore, since it is necessary to provide a flat surface having a considerable length on both side surfaces of the socket portion 3b, there is a problem that the lever housing 3 is large and therefore increases in weight. In addition, when the number of shift stages is increased and two select positions are provided in the same rotational direction, the above-described flat surface becomes larger according to the one provided with the third pressing pin assembly, so that the weight is further increased and the second is increased. There arises a problem that the cost increases by the amount of the three pressing pin assemblies. Further, according to the push pin assembly on the reverse side provided with the press piston and the second spring, the press pin assembly 6 may be the same as the conventional one, but the push pin assembly on the reverse side has an increased number of parts. Since the structure is complicated, there is a problem that the cost is increased and the weight is increased. The object of the present invention is to solve each of these problems.

  To this end, the transmission / return select return device according to the first aspect of the present invention includes an operating shaft that is integrally provided with a shift-and-select lever and is rotatably supported on the casing, and is capable of rotating the operating shaft. The shift and select lever selects one of a plurality of fork shafts by selecting movement in the rotational direction of the shift and select shaft, and selects the fork shaft selected by shifting movement in the reciprocating direction. In a transmission that reciprocates and switches a transmission gear, a select return housing that is integrally provided on an operating shaft and has a cylinder portion that extends in a radial direction, and the cylinder portion that is slidably supported in the longitudinal direction by the cylinder portion Piston part with cam follower provided at the tip protruding from the part And is rotatably supported by the operating shaft and extends in the radial direction so that the center plane in the thickness direction substantially coincides with the center line of the cylinder portion, and the cylinder portion, the piston member, and the cam follower are relatively shaken. A plate-shaped cam plate that is formed with an opening that is movably accommodated and is engaged with the casing so as to allow only movement in the direction of the operating shaft, and a cam member that biases the piston member outwardly with respect to the cylinder portion. Is provided with a select return device consisting of a spring that elastically presses against a cam surface formed on a portion of the opening opposite to the operating shaft, and the cam surface is at the center of the operating shaft at a neutral position located between the movement range of the cam follower. And the angle of inclination on opposite sides of the neutral position was opposite to each other. It is an feature.

  In the select return device of the transmission described in the preceding paragraph, the cam surface is defined by a boundary at an intermediate position where the movement amount of the piston member with respect to the relative rotation angle between the cylinder portion and the cam plate with the neutral position as the origin is different from the neutral position. It is preferable to change the inclination angle with the vicinity of the intermediate position as a boundary so as to increase.

  In the select return device for a transmission according to the preceding item 2, it is preferable that the cam follower is a roller rotatably supported at a tip end portion of a piston member by a pivot pin parallel to the operation shaft.

  In the select return device of the transmission described in the preceding item 3, the cam plate has a notch shape in which the opposite side to the operation shaft is opened at a position away from the operation shaft or a long hole shape that is long in the radial direction with respect to the operation shaft. A locking pin that is fixed to the casing in parallel with the operating shaft is engaged with the locking portion to lock the cam plate to the casing so as to allow only movement in the direction of the operating shaft. Is preferred.

  In the select return device for a transmission according to the preceding item 4, a stopper surface is formed at a position facing the side surface of the cylinder portion of the select return housing at the opening of the cam plate, and the side surface of the cylinder portion is in contact with the stopper surface. It is preferable to form a contact surface.

  According to the first aspect of the present invention, the select return housing is provided integrally with the operating shaft and has a cylinder portion extending in the radial direction, and the tip that is supported by the cylinder portion so as to be slidable in the longitudinal direction and protrudes from the cylinder portion. A piston member provided with a cam follower on the part, and a cylinder part which is supported by an operating shaft so as to be rotatable and extends in the radial direction so that a center plane in the thickness direction substantially coincides with a center line of the cylinder part; A plate-shaped cam plate formed with an opening for relatively swingably accommodating the piston member and the cam follower and engaged with the casing so as to allow only the movement in the operation shaft direction, and the piston member with respect to the cylinder portion Is a spring that elastically presses the cam follower against the cam surface formed on the part of the opening opposite to the operating shaft. The cam surface has the maximum distance from the center of the operating shaft at the neutral position located between the movement range of the cam follower, and the inclination angles on both sides are opposite to each other with the neutral position as a boundary. Therefore, even if the select return housing is rotated in any direction from the neutral position, the cam follower moved along the cam surface compresses the spring via the piston member and returns the shift and select lever to the neutral position. The select return force can be generated by only one set of piston member and spring. Further, since the shift and select lever, the select return housing, the piston member, the spring and the cam plate are integrally moved in the axial direction at the time of shifting, the whole can be made compact. Furthermore, the cam plate can be formed as a relatively thin plate having no relation to the shift stroke and can be press-molded, so that the manufacturing cost can be reduced.

  The cam surface is tilted around the middle position so that the movement of the piston member relative to the relative rotation angle between the cylinder and cam plate with the neutral position as the origin increases at the middle position that is different from the neutral position. According to the invention of claim 2 in which the angle is changed, even if two select positions are provided in the same rotational direction in order to increase the number of shift stages, the cam can be increased without increasing the number of parts or complicating the structure. By simply changing the shape of the cam surface of the plate, it is possible to cope with clarification of the intermediate select position.

  According to the invention of claim 3, the cam follower is operated lightly because the resistance between the cam surface and the cam follower is reduced. The roller is rotatably supported at the tip of the piston member by a pivot pin parallel to the operation shaft. A select return device can be obtained.

  The cam plate is formed with a notch shape that opens away from the operating shaft at the opposite side of the operating shaft or a long hole-shaped latching portion that is long in the radial direction with respect to the operating shaft, and is parallel to the operating shaft. According to the invention of claim 4, the cam plate is locked to the casing so as to allow only movement in the direction of the operating shaft. It is possible to simplify the latch structure for locking so as to allow only movement in the direction of the operating shaft.

  6. The invention according to claim 5, wherein the opening of the cam plate is formed with a stopper surface at a position facing the side surface of the cylinder portion of the select return housing, and an abutting surface is formed on the side surface of the cylinder portion. Accordingly, the shift and select lever can be reliably stopped at a predetermined position with a simple structure.

  In the following, the best mode for carrying out the selective return device for a transmission according to the present invention will be described with reference to FIGS. In this embodiment, the present invention is applied to a manual transmission having six forward speeds and one reverse speed as shown in FIG. The manual transmission of this embodiment includes a casing 10, a shift and select shaft (operation shaft) 11, a housing 12, a shift lever 15, and a select return device 20.

  As shown mainly in FIG. 1, a housing 12 is integrally fixed to one end portion of a shift and select shaft 11 supported by a transmission casing 10 so as to be rotatable and reciprocally movable, and a select portion is selected at the other end portion. A return device 20 is provided. A cylindrical socket portion 12 a that protrudes radially on one side of the housing 12 and is integrally formed so that the center axis is orthogonal to the shift and select shaft 11 is inserted into the tip of a manual shift lever 15 via a sliding body 13. The small ball portion 15a is rotatably connected. When the shift lever 15 is in an inoperative state, the shift lever 15 extends to the outside of the casing 10 in a direction substantially orthogonal to the shift and select shaft 11, and a support portion 16 having a hemispherical support surface fixed to an intermediate portion thereof is The spring 18 interposed between the spring receiver 18a fixed in the opening is slidably and elastically pressed against the spherical seat 17 provided in the casing 10, whereby the shift lever 15 swings against the shift tower 10a. It is supported movably. A pair of rotation restricting pins 17a fixed to the shift tower 10a are inserted into a pair of notches 16a formed on opposite side portions of the support portion 16 so that the shift lever 15 rotates about its axis. It is preventing. A dust-proof boot 19 is provided between the outer periphery of the opening of the shift tower 1 a and the shift lever 15.

  If the shift lever 15 is manually swung around the support portion 16 as indicated by an arrow in the drawing of FIG. 1, the shift and select shaft 11 is indicated by an arrow in the axial direction via the housing 12. When the shift lever 15 is reciprocated and the shift lever 15 is swung in a direction perpendicular to the paper surface of FIG. 1, the shift and select shaft 11 is rotated about the axis via the housing 12. A housing 12 fixed to one end of the shift and select shaft 11 and having a socket part 12a formed on one side in the radial direction, and a tip part rotatably connected to the socket part 12a and an intermediate part swinging to the casing 10. The shift lever 15 movably supported constitutes an operating device for rotating and reciprocating the shift and select shaft 11.

  As shown in FIGS. 1 and 2, the select return device 20 mainly includes a select return housing 21, a piston member 22 provided thereon, a roller (cam follower) 23, a spring 24, and a cam plate 25.

  The select return housing 21 is integrally fixed to the other end of the shift and select shaft 11 on the opposite side of the housing 12 via a bolt 28, and extends in a radial direction perpendicular to the shift and select shaft 11. A shift and select lever 21d extending in a different radial direction is integrally formed. The boss portion of the select return housing 21 fixed to the shift and select shaft 11 and the cylinder portion 21 a are slightly offset in the axial direction of the shift and select shaft 11. On the inner surface of the cylinder portion 21a, the piston member 22 is supported so as to be freely slidable in the longitudinal direction while constraining the rotation about the longitudinal axis, and a radius is provided by a spring 24 interposed between the inner surface of the cylinder portion 21a. It is biased outward in the direction. A roller 23 is rotatably supported by a pivot pin 23a parallel to the shift and select shaft 11 on a bifurcated portion 22a formed at the distal end portion of the piston member 22 projecting radially outward from the cylinder portion 21a. Yes.

  The cam plate 25 is a plate having a constant thickness that is press-formed by punching. One end of the cam plate 25 that is rotatably supported by the shift and select shaft 11 is brought into contact with the end face of the boss portion of the select return housing 21 to stop the cam plate 25. The ring 27 holds the stopper. The cam plate 25 extends in the radial direction from one end portion supported by the shift and select shaft 11, and is arranged so that the center surface in the thickness direction substantially coincides with the center line of the cylinder portion 21a. An opening 26 is formed to accommodate the member 22 and the roller 23 in a relatively swingable manner. The cam plate 25 is formed with a U-shaped latching portion 25 a having an opening on the opposite side to the shift and select shaft 11 at a protruding portion formed on the opposite side to the shift and select shaft 11. A locking pin 29 fixed to the casing 10 is engaged with the latching portion 25a, and the cam plate 25 is restricted from rotating around the shift and select shaft 11 and only allows movement in the direction of the shift and select shaft 11. As shown in FIG. The detent pin 29 is an extension of a fixed shaft that supports an idler gear of a transmission gear train, for example. Moreover, the latching | locking part 25a is good also as a long hole shape long to radial direction with respect to the shift and select shaft 11, instead of notch shapes, such as U shape.

  As shown mainly in FIG. 2, the opening 26 of the cam plate 25 has a cam surface 26 a formed at a portion opposite to the shift and select shaft 11, and is provided at the tip of the piston member 22 urged by the spring 24. The roller 23 is elastically pressed against the cam surface 26a. In this embodiment, since the present invention is applied to a manual transmission having six forward speeds and one reverse speed as shown in FIG. 3 (a), the roller 23 has a cam as shown in FIG. It is moved on the surface 26a between both end positions S1 and S2 (5.6 speed position S1 and reverse position S2), and the neutral position (3.4 speed position) N and intermediate position (1. Second gear position) S3 is located. The cam surface 26a maximizes the distance from the center of the shift-and-select shaft 11 at the neutral position N, and has the same inclination angle on both sides of the neutral position N as opposite to each other. The amount of movement of the piston member 22 relative to the relative rotation angle between the cylinder portion 21a and the cam plate 25 increases rapidly with the intermediate position (1.2 speed position) S3 as a boundary. The inclination angle of the cam surface 26a on the reverse position S2 side is increased from that. As a result, the ratio of the increase of the select return force F to the relative rotation angle between the cylinder portion 21a and the cam plate 25 with the neutral position N as the origin is the 3.4 speed position N as shown in FIG. And 5.6 speed position S1 and between 3.4 speed position N and 1.2 speed position S3, and 1.2 speed positions S3 and 5 between 1.2 speed position S3 and reverse position S2. The characteristic which becomes larger than between the 6th speed position S1 is acquired.

  Further, as shown in FIG. 2, stopper surfaces 26b and 26c are formed in the opening 26 of the cam plate 25 at positions opposite to both side surfaces of the cylinder portion 21a of the select return housing 21, and on both side surfaces of the cylinder portion 21a. Contact surfaces 21b and 21c that contact the stopper surfaces 26b and 26c are formed. As a result, the select return housing 21 comes into contact with the stopper surface 26b at the 5.6th speed position S1 to prevent further rotation, and the contact surface 21c becomes the stopper surface 26c at the retracted position S2. A further rotation is prevented by abutting against.

  In the above-described embodiment, if the shift lever 15 is manually swung in the direction orthogonal to the paper surface of FIG. 1, the shift and select shaft 11 is selected around the axis via the operating device including the shift lever 15 and the housing 12. As a result, the shift and select lever 21d formed integrally with the select return housing 21 is rotated, and its tip engages with one of a plurality of shift pieces (not shown) of the fork shafts. Select the fork shaft. In this state, if the shift lever 15 is manually swung as indicated by an arrow in the plane of FIG. 1, the shift-and-select shaft 11 is moved in the axial direction as indicated by the arrow via the actuator. As a result, the selected fork shaft reciprocates and the transmission gear is switched. During this shift movement, the select return housing 21, the piston member 22, the roller 23, the spring 24, and the cam plate 25 are moved together with the shift and select shaft 11 to prevent the latching portion 25a of the cam plate 25 from rotating. Sliding is performed between the pins 29.

  According to the above-described embodiment, even when the select return housing 21 is rotated in any direction from the 3.4th speed position N that is the neutral position with respect to the cam plate 25 by the select motion, the select return housing 21 moves along the cam surface 26a. Since the roller 23 compresses the spring 24 via the piston member 22, the select return force F for returning the shift and select lever 21 d to the 3.4th speed position N is applied by the pair of piston member 22 and the spring 24. Can be generated. Further, the piston member 22 moves with respect to the relative rotation angle between the cylinder portion 21a and the cam plate 25 with the neutral position N as the origin, with the 1.2th speed position S3 between the 3.4th speed position N and the reverse position S2 as a boundary. The inclination angle of the cam surface 26a is increased with the vicinity of the 1.2th speed position S3 as a boundary so that the amount increases rapidly, and thereby the cam plate 25 can be increased without increasing the number of parts or complicating the structure. Only by changing the shape of the cam surface 26a, a select return device that can clearly determine the 1.2-speed position S3 upon selection by the shift lever 15 is obtained. Further, the members 21 to 25 constituting the select return device 20 do not move together with the shift and select shaft 11 during the select movement and move relative to each other. Since the sliding is performed between the rotation stop pin 29a and the rotation preventing pin 29, the select return device 20 can be made compact as a whole. Further, the cam plate 25 can be formed as a relatively thin plate having no relation to the shift stroke and can be press-molded, so that the manufacturing cost can be reduced.

  In the above-described embodiment, the roller 23 rotatably supported at the tip end portion of the piston member 22 by the pivot pin 23a parallel to the operation shaft 11 is used as a cam follower that comes into contact with the cam surface 26a of the cam plate 25. By doing so, it is possible to obtain a select return device that operates lightly by reducing the resistance between the cam surface 26a and the cam follower. However, the present invention is not limited to this, and the cam follower can be formed by a protrusion formed integrally with the tip of the piston member 22.

  Further, in the above-described embodiment, the cam plate 25 has a notch shape in which the opposite side to the operation shaft 11 is opened at a position away from the operation shaft 11 or a long hole-shaped latching portion 25a that is long in the radial direction with respect to the operation shaft. And a locking pin 29 fixed to the casing 10 in parallel with the operating shaft 11 is engaged with the latching portion 25a so that the cam plate 25 is allowed to move only in the direction of the operating shaft 11 in the casing 10. In this way, the latch structure for locking the cam plate 25 to the casing 10 so as to allow only the movement in the direction of the operation shaft 11 can be simplified. However, the present invention is not limited to this, and a rod extending in parallel with the operation shaft 11 is fixed to the cam plate 25 at a position away from the operation shaft 11, and this rod can be freely slid into a hole formed in the casing 10. And the cam plate 25 may be locked to the casing 10 so as to allow only the movement in the direction of the operating shaft 11.

  Further, in the above-described embodiment, the stopper surface 26b, 26c is formed in the opening 26 of the cam plate 25 at a position facing the side surface of the cylinder portion 21a of the select return housing 21, and the stopper surface 26b, In this way, the select return housing 21 can be connected to the cylinder portion 21a at the 5.6 speed position S1 or the reverse position S2 without using a special member. In this state, it can be stopped reliably.

  In the embodiment described above, the case where the present invention is applied to a manual transmission having a shift pattern of 6 forwards and 1 reverse as shown in FIG. 3 is described, but the present invention is not limited to this. It is also possible to apply to 5 forward steps, 1 reverse step, or other shift patterns as shown in FIG. When the present invention is applied to a shift pattern of five forward speeds and one reverse speed, the 1.2-speed position S3 does not exist between the 3.4-speed position N and the reverse position S2. Of these, all the operational effects can be obtained except for the operational effect that the intermediate shift position can be clearly determined.

  In the above-described embodiment, the case where the present invention is applied to a manual transmission has been described. However, the present invention includes an operating shaft that is rotated and reciprocated by an operating device, and a select motion in the rotating direction of the operating shaft. As long as it is a transmission that selects one of a plurality of fork shafts and reciprocates the fork shaft selected by a reciprocating movement in the reciprocating direction to switch the transmission gear, the operation device is not limited to a manual operation, The present invention can also be applied to an automatic transmission that automatically controls the operating device based on the operating state of the vehicle such as the accelerator opening, the vehicle speed, and the engine speed.

It is sectional drawing which shows the principal part of the select return apparatus of the transmission by this invention. It is 2-2 sectional drawing of FIG. It is a figure which shows an example of the shift shift pattern to which the select return apparatus of a transmission is applied. It is a figure which shows the other example of the shift shift pattern to which the select return apparatus of a transmission is applied. It is sectional drawing which shows the principal part of an example of the select return apparatus of the transmission by a prior art. FIG. 6 is a cross-sectional view taken along 6-6 in FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Casing, 11 ... Actuation shaft (shift and select shaft), 20 ... Select return device, 21 ... Select return housing, 21a ... Cylinder part, 21b, 21c ... Contact surface, 21d ... Shift and select lever, 22 ... Piston Member, 23 ... Cam follower (roller), 23a ... Pivot pin, 24 ... Spring, 25 ... Cam plate, 25a Hook, 26 ... Opening, 26a ... Cam surface, 26b, 26c ... Stopper surface, 29 ... Non-rotating pin , N: neutral position (3.4 speed position), S3: intermediate position (1.2 speed position).

Claims (5)

The shift and select lever comprises an operating shaft that is integrally provided and supported by the casing so as to be able to rotate and reciprocate, and an operating device that rotates and reciprocates the operating shaft. In the transmission that selects one of a plurality of fork shafts by a selection movement in the rotation direction of the AND selection shaft and switches the transmission gear by reciprocating the selected fork shaft by a shift movement in the reciprocation direction. A select return housing integrally provided on the operating shaft and having a cylinder portion extending in the radial direction, and a piston having a cam follower provided at a tip portion that is supported by the cylinder portion so as to be slidable in the longitudinal direction and protrudes from the cylinder portion A member, and is supported rotatably on the operating shaft. An opening is formed to extend in the radial direction so that a center plane in the thickness direction substantially coincides with the center line of the cylinder portion, and accommodates the cylinder portion, the piston member, and the cam follower in a swingable manner. A plate-shaped cam plate engaged so as to allow only movement in the operation shaft direction with respect to the casing, and the piston member is urged outwardly with respect to the cylinder portion to operate the cam follower with the operation of the opening. A select return device comprising a spring that elastically presses against a cam surface formed on a portion opposite to the shaft, and the cam surface is located from a center of the operating shaft at a neutral position located between a movement range of the cam follower. And the inclination angles on both sides of the neutral position are opposite to each other. Select return device for a transmission, characterized in that it was. 2. The select return device for a transmission according to claim 1, wherein the cam surface has an amount of movement of the piston member with respect to a relative rotation angle of the cylinder portion and the cam plate with the neutral position as an origin, and the neutral position. A selective return device for a transmission, characterized in that the inclination angle is changed with the vicinity of the intermediate position as a boundary so as to increase at different intermediate positions. The select return device for a transmission according to claim 1 or 2, wherein the cam follower is a roller rotatably supported at a tip end portion of the piston member by a pivot pin parallel to the operation shaft. Selective return device for transmission. The select return device for a transmission according to any one of claims 1 to 3, wherein the cam plate has a notch shape in which a side opposite to the operation shaft is opened at a position away from the operation shaft or the same. A long-hole-shaped latching portion that is long in the radial direction with respect to the operating shaft is formed, and a locking pin fixed to the casing in parallel with the operating shaft is engaged with the latching portion, so that the cam plate is connected to the casing. And a select return device for a transmission, wherein the device is locked so as to allow only movement in the direction of the operating shaft. In the select return device of the transmission according to any one of claims 1 to 4, a stopper surface is formed at a position facing the side surface of the cylinder portion of the select return housing in the opening of the cam plate, A select return device for a transmission, wherein a contact surface that contacts the stopper surface is formed on a side surface of the cylinder portion.

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