Gear shift actuator

A gear shift actuator comprising:

• a linear drive assembly comprising:
• a driven component configured to actuate a shift fork;
• a rotary member which is supported to be rotatable, but unmovable in an axial direction defined by its a rotary axis of the rotary member;
• and
• an electric motor configured to rotate the rotary member,
• wherein the driven component is driven by rotary movement of the rotary member for linear movement parallel to the axial direction in a first direction from a neutral position to a first gear engaged position and back to neutral, when the rotary member is driven to rotate first in a first rotational direction and then in a second rotational direction opposite to the first rotational direction, and in a second direction opposite to the first direction from the neutral position to a second gear engaged position and back to neutral, when the rotary member is first driven to rotate in the second rotational direction and then in the first of rotational direction, wherein the rotary member is a shaft,
• wherein first and second barrel cams are configured engage with the shaft in a torque-proof manner while being slidable in axial direction along the shaft, and
• wherein the first and second barrel cams are disposed between spaced apart first and second end stops which are fixed in axial direction to limit axial movement of the first and second barrel cams, respectively,
• wherein a spring mechanism is disposed between the first and second barrel cams to bias the first and second barrel cams apart and towards the first and second end stops, respectively,
• wherein the first and second barrel cams comprise first and second cam grooves on surfaces thereof, respectively,
• wherein the driven component carries first and second cam followers spaced apart and aligned in axial direction and arranged to be received in the first and second cam grooves, respectively,
• wherein each of the first and second cam grooves extends from a starting point along a circumferential start portion, followed by a helical portion extending further towards an outer end portion of the respective one of the first and second barrel cams, which is followed by a circumferentially extending end portion,
• wherein the starting points of the first and second cam grooves are open to recessed surface sectors of the first and second barrel cams, respectively, which allow movement of the first and second cam followers, respectively, in a direction parallel to the axial direction in a region between the first and second cam grooves, respectively, and an inner end portion of the first and second barrel cams remote therefrom, and
• wherein the first and second barrel cams are rotationally oriented with respect to each other such that the start portions of the first and second cam grooves are aligned so that, when the first cam follower is in the start portion of the first cam groove, the second cam follower is in the start portion of the second cam groove, so that when the rotary member is then rotated in the first of rotational direction, the first cam groove is moved along the first cam follower which thereby is driven by the helical portion to move the driven component in the first direction, while the second cam follower is free to follow the movement in the recessed surface sector of the second barrel cam, is rotated in the second rotational direction, the second cam groove is moved along the second cam follower which thereby is driven by the helical portion to move the driven component in the second direction, while the first cam follower is free to follow the movement in the recessed surface sector of the first barrel cam.