Transmission system

The transmission system of any one of the preceding claims, wherein the engagement members in the second set of engagement members are angularly distributed evenly about the second annular member.

The transmission system of any one of the preceding claims, the first selector ring includes a first set of recesses formed through the first annular member, wherein each recess in the first set of recesses is sized, shaped and positioned to receive a respective one of the engagement members in the second set of engagement members.

The transmission system of any one of the preceding claims, the second selector ring includes a second set of recesses formed through the second annular member, wherein each recess in the second set of recesses is sized, shaped and positioned to receive a respective one of the engagement members in the second set of engagement members.

The transmission system of any one of the preceding claims, including an actuator assembly arranged to control movement of the first and second selector rings.

The transmission system of any one of the preceding claims, wherein the first selector assembly is mounted on a shaft, a first gear element is rotatably mounted on the shaft, a second gear element is rotatably mounted on the shaft, and the first selector assembly is arranged to selectively lock the first and second gear elements for rotation with the first shaft.

The transmission system of any one of the preceding claims, wherein, in a condition wherein the first gear element is engaged by the first and second sets of engagement members and is locked for rotation in forward and reverse torque directions, one of the first and second sets of engagement members is in a loaded condition and the other of the first and second sets of engagement members is in an unloaded condition.

The transmission system of any one of the preceding claims, wherein the first gear selector assembly is arranged to selectively engage the second gear element with the following operational modes:

• lock the second gear element for rotation with the shaft in forward and reverse torque directions;
• lock the second gear element for rotation with the shaft in the forward torque direction and not lock in the reverse torque direction;
• and lock the second gear element for with rotation with the shaft in the reverse torque direction and not lock in the forward torque direction.

The transmission system of any one of the preceding claims, wherein, in a condition wherein the second gear element is engaged by the first and second sets of engagement members and is locked for rotation in forward and reverse torque directions, one of the first and second sets of engagement members is in a loaded condition and the other of the first and second sets of engagement members is in an unloaded condition.

The transmission system of any one of the preceding claims, wherein the first gear selector assembly is arranged to provide torque support during a gear shift, to ensure that there is no loss of drive during the gear shift.

The transmission system of any one of the preceding claims, including a first input shaft that is directly connected to the output of a drive source, and a second input shaft that is connected to the output of the drive source via a friction clutch.

The transmission system of any one of the preceding claims, wherein the third gear selector assembly includes a further selector ring, and the actuator assembly includes a further shift fork assembly, the further shift fork assembly including a further shift fork arranged to control axial movement of the further selector ring.

The transmission system of any one of the preceding claims, including an output shaft, wherein the third gear selector assembly is mounted on one of the output shaft, the second lay shaft and a sleeve mounted on the second lay shaft, at least one further gear element is rotatably mounted on the same shaft as third gear selector assembly, and the third gear selector assembly is arranged to selectively lock the at least one further gear element for rotation with the shaft on which it is mounted.

The transmission system of any one of the preceding claims, wherein the third gear selector assembly comprises a pre-select selector assembly, which is arranged to pre-select a new.

A drive train including a drive source, a friction clutch device and a transmission system according to any one of the preceding claims.