Shift device

1. A shift device, comprising:

a first member axially movably supported on a shaft, the first member comprising a coupling portion for coupling with a coupling mechanism which is in communication with an actuator of a shifting system;

a second member axially movably supported on the shaft, and

an elastic member arranged on the shaft and elastically compressible in an axial direction of the shaft, wherein

the second member is engaged with the first member such that an axial movement of the first member is transmitted to the second member and vice versa via the elastic member,

the elastic member, by being compressed, allows relative axial movement in both a first axial direction and an opposite second axial direction between the first member and the second member so that one of the first member and the second member is displaced from an initial position relative to the other of the first member and the second member, and

the elastic member, in a compressed state, exerts an urging force on the first member and the second member urging the one of the first member and the second member towards the initial position relative to the other of the first member and the second member;

wherein the shift device further comprises two inner sleeves axially movably supported on the shaft,

the first member comprises an outer sleeve disposed radially outwardly of the inner sleeves,

the outer sleeve is axially movably supported on the shaft via the inner sleeves,

the inner sleeves are axially movable with respect to the outer sleeve, and

the elastic member is arranged axially between the two inner sleeves.

2. The shift device according to claim 1 , wherein

one of the two inner sleeves is arranged at one axial end of the outer sleeve at least partially inside the outer sleeve,

the other of the two inner sleeves is arranged at an other axial end of the outer sleeve at least partially inside the outer sleeve,

the inner sleeves each have an axial end, which is arranged inside the outer sleeve, and an outer abutment projects radially outwardly at the axial end from an outer peripheral surface of the inner sleeve and extends in a circumferential direction of the inner sleeve, and

the outer sleeve has at each of the axial ends an inner abutment projecting radially inwardly from an inner peripheral surface of the outer sleeve and extending in a circumferential direction of the outer sleeve, and

the outer abutment of each inner sleeve engages a respective inner abutment of the outer sleeve such that an axial movement of the inner sleeves relative to the outer sleeve is restricted.

3. The shift device according to claim 2 , wherein

the elastic member is arranged inside the outer sleeve and urges the inner sleeves in the axial direction towards the respective axial end of the outer sleeve,

when the one of the first member and the second member is in the initial position relative to the other of the first member and the second member, the outer abutments of the inner sleeves abut the respective inner abutment of the outer sleeve, and,

when the one of the first member and the second member is displaced from the initial position relative to the other of the first member and the second member, one of the inner sleeves is displaced relative to the outer sleeve so as to space the outer abutment from the respective inner abutment, thereby compressing the elastic member between the inner sleeves.

4. The shift device according to claim 2 , wherein

at least one inner sleeve includes an axial protrusion formed on an outer circumferential edge portion of the outer abutment on an axial end side of the inner sleeve, and

the axial protrusion partially covers an outer peripheral surface of an axial end portion of the elastic member.

5. The shift device according to claim 2 , wherein

an inner peripheral surface of the inner abutments of the outer sleeve slidably contacts the outer peripheral surface of the respective inner sleeve.

6. The shift device according to claim 1 , wherein

the second member includes a first bearing portion and a second bearing portion for axially movably supporting the second member on the shaft,

the outer sleeve of the first member and the inner sleeves are interposed between the first bearing portion and the second bearing portion,

when the one of the first member and the second member is in the initial position relative to the other of the first member and the second member, one of the inner sleeves abuts the first bearing portion of the second member and the other of the inner sleeves abuts the second bearing portion of the second member, and,

when the one of the first member and the second member is displaced from the initial position relative to the other of the first member and the second member, one of the inner sleeves is displaced from the first or second bearing portion so as to space the respective inner sleeve from the first or second bearing portion, thereby compressing the elastic member between the inner sleeves.

7. The shift device according to claim 1 , wherein

the elastic member is a coil spring.

8. The shift device according to claim 7 , wherein

the elastic member includes at least a first coil spring and a second coil spring, and

the second coil spring is arranged on a radially outer side of the first coil spring so as to circumferentially surround the first coil spring.

9. A shifting system comprising:

an actuator,

a shift member for shifting a shift sleeve configured to engage and disengage gears of a transmission, and

a shift device that comprises:

a first member axially movably supported on a shaft, the first member comprising a coupling portion for coupling with a coupling mechanism which is in communication with the actuator of the shifting system,

a second member axially movably supported on the shaft, and

an elastic member arranged on the shaft and elastically compressible in an axial direction of the shaft;

wherein the actuator is in communication with the first member the shift device, and

the shift member is in communication with the second member of the shift device,

when the actuator is operated, the first member is moved in the axial direction by a specific amount,

when axial movement of the shift member is not restricted, the axial movement of the first member is transmitted to the second member so that the second member is moved in the axial direction by the specific amount,

when axial movement of the shift member is restricted, the first member is displaced from an initial position relative to the second member, thereby compressing the elastic member, and

when restriction on the axial movement of the shift member is released, the elastic member urges the first member to the initial position relative to the one of the first member and the second member, thereby axially moving the shift member by the specific amount so as to perform a shifting operation;

wherein the shift device further comprises two inner sleeves axially movably supported on the shaft,

the first member comprises an outer sleeve disposed radially outwardly of the inner sleeves,

the outer sleeve is axially movably supported on the shaft via the inner sleeves,

the inner sleeves are axially movable with respect to the outer sleeve, and

the elastic member is arranged axially between the two inner sleeves.

10. The shifting system according to claim 9 , wherein

the shift member and the second member are formed integrally.

11. The shifting system according to claim 10 , wherein

the shift member is a shift fork configured to engage the shift sleeve and reciprocate the shift sleeve in the axial direction.

12. The shifting system according to claim 9 , wherein

the elastic member is configured to be compressible in an installed state by at least the specific amount.

13. A shift device, comprising:

a first member axially movably supported on a shaft, the first member comprising a coupling portion for coupling with a coupling mechanism which is in communication with an actuator of a shifting system;

a second member axially movably supported on the shaft, and

an elastic member arranged on the shaft and elastically compressible in an axial direction of the shaft, wherein

the second member is engaged with the first member such that an axial movement of the first member is transmitted to the second member and vice versa via the elastic member,

the elastic member, by being compressed, allows relative axial movement in both a first axial direction and an opposite second axial direction between the first member and the second member so that one of the first member and the second member is displaced from an initial position relative to the other of the first member and the second member, and

the elastic member, in a compressed state, exerts an urging force on the first member and the second member urging the one of the first member and the second member towards the initial position relative to the other of the first member and the second member,

wherein the shift device further comprises two inner sleeves axially movably supported on the shaft,

the first member comprises an outer sleeve disposed radially outwardly of the inner sleeves,

the outer sleeve is axially movably supported on the shaft via the inner sleeves,

the inner sleeves are axially movable with respect to the outer sleeve, and

the elastic member is arranged axially between the two inner sleeves

wherein one of the two inner sleeves is arranged at one axial end of the outer sleeve at least partially inside the outer sleeve,

the other of the two inner sleeves is arranged at an other axial end of the outer sleeve at least partially inside the outer sleeve,

the inner sleeves each have an axial end, which is arranged inside the outer sleeve, and an outer abutment projects radially outwardly at the axial end from an outer peripheral surface of the inner sleeve and extends in a circumferential direction of the inner sleeve, and

the outer sleeve has at each of the axial ends an inner abutment projecting radially inwardly from an inner peripheral surface of the outer sleeve and extending in a circumferential direction of the outer sleeve, and

the outer abutment of each inner sleeve engages a respective inner abutment of the outer sleeve such that an axial movement of the inner sleeves relative to the outer sleeve is restricted,

wherein at least one inner sleeve includes an axial protrusion formed on an outer circumferential edge portion of the outer abutment on an axial end side of the inner sleeve, and

the axial protrusion partially covers an outer peripheral surface of an axial end portion of the elastic member.