A continuously variable transmission includes a first shaft driveably connected to a power-plant and having a first pair of sheave disks, and a second shaft having a second pair of sheave disks. A tension member is connected to the first and second pairs of disks such that power is transmittable between the first and second shafts. A third shaft is selectively driveably connected to the second shaft via a clutch. The clutch includes an inner race fixed to one of the second and third shafts, and an outer race fixed to a gear and having an inner surface circumscribing the inner race. At least one pawl is biased to couple the races in a fixed relationship for common rotation. The clutch further includes an electric coil and an armature configured to engage the pawl to decouple the races in response to current being supplied to the electric coil.

A continuously variable transmission includes a first shaft driveably connected to a power-plant and having a first pair of sheave disks, and a second shaft having a second pair of sheave disks. A tension member is connected to the first and second pairs of disks such that power is transmittable between the first and second shafts. A third shaft is selectively driveably connected to the second shaft via a clutch. The clutch includes an inner race fixed to one of the second and third shafts, and an outer race fixed to a gear and having an inner surface circumscribing the inner race. At least one pawl is biased to couple the races in a fixed relationship for common rotation. The clutch further includes an electric coil and an armature configured to engage the pawl to decouple the races in response to current being supplied to the electric coil.

A drive sheave assembly of a continuously variable transmission is provided that includes a post, a fixed sheave, a movable sheave assembly, a sleeve and an engine braking assembly. The engine braking assembly includes an axial activation member, a one-way engagement member and a flange. The axial activation member is statically mounted within a central recess of the fixed sheave. The axial activation member is movably connected with the one-way engagement member. A central passage of the one-way engagement member is configured to engage a portion of the sleeve. The flange is coupled to the one-way engagement member to selectively engage a side of an endlessly looped member with axial movement of the one-way engagement member during an engine braking condition.

A drive sheave assembly of a continuously variable transmission is provided that includes a post, a fixed sheave, a movable sheave assembly, a sleeve and an engine braking assembly. The engine braking assembly includes an axial activation member, a one-way engagement member and a flange. The axial activation member is statically mounted within a central recess of the fixed sheave. The axial activation member is movably connected with the one-way engagement member. A central passage of the one-way engagement member is configured to engage a portion of the sleeve. The flange is coupled to the one-way engagement member to selectively engage a side of an endlessly looped member with axial movement of the one-way engagement member during an engine braking condition.

A variable pitch pulley includes a rotary shaft, a fixed sheave fixed to the rotary shaft, and a moving sheave forming a belt groove with the fixed sheave. The moving sheave includes an inner sheave and an outer sheave radially stacked on the inner sheave. The pitch pulley further includes a moving sheave-positing unit determining relative positions of the inner and outer sheaves. The inner and outer sheaves are simultaneously moved in an axial direction of the rotary shaft in a first moving mode, and only the outer sheave is moved in the axial direction in a second moving mode.

A continuously variable transmission includes four shift elements to establish three forward driving ranges and one reverse driving range. Two of the forward driving ranges utilize recirculating power flow paths in which the power transmitted through the variator is much smaller than the power transmitted by the transmission. Both variator sheaves rotate about axes that are offset from the input axis such that neither sheave is partially submerged in transmission fluid.

A continuously variable transmission includes four shift elements to establish three forward driving ranges and one reverse driving range. Two of the forward driving ranges utilize recirculating power flow paths in which the power transmitted through the variator is much smaller than the power transmitted by the transmission. Both variator sheaves rotate about axes that are offset from the input axis such that neither sheave is partially submerged in transmission fluid.

A pulley assembly is provided for mounting on a rotatable shaft of an agricultural harvester and is operable in a high-speed configuration or a low-speed configuration. The pulley assembly comprises a high-speed pulley with a high-speed running surface for receiving a drive belt when the pulley assembly is in the high-speed configuration and a low-speed pulley with a low-speed running surface for receiving a drive belt when the pulley assembly is in the low-speed configuration. The pulley assembly has three sets of teeth extending from surfaces of the two pulleys. In the low-speed configuration, the running surfaces of the low-speed pulley and high-speed pulley are axially aligned and the first set of teeth and the second set of teeth are engaged. In the high-speed configuration, the running surface of the high-speed pulley is exposed for receiving the drive belt.

A hybrid drive apparatus is provided to allow setting a variety of driving modes while achieving improvement in transmission efficiency. The hybrid drive apparatus includes an engine, first and second motor generators and a planetary gear mechanism. An output shaft of the first motor generator, an output shaft of an engine and an output shaft of the second motor generator, and an input shaft of the continuously variable transmission mechanism are coupled respectively to a sun gear, ring gear and carrier of the planetary gear mechanism. The hybrid drive apparatus includes first, second and third clutches which can switch engagement/disengagement respectively between the output shaft of the engine and the ring gear, between the carrier and the ring gear, and on the input shaft of the continuously variable transmission mechanism.

A pulley assembly for a high-speed continuously variable transmission includes a drive pulley, a shaft sleeve, a movable pulley, rollers, and a back pressure disc. The movable pulley has a shaft portion fitted on the shaft sleeve. The movable pulley has a disc chamber radially formed with multiple pairs of retaining wall pieces. A receiving room is defined between each pair of the retaining wall pieces. The bottom of the receiving room has an inclined push surface. The rollers are received in the receiving rooms. The back pressure disc includes a disc body having a complete inner conical surface. The back pressure disc is subject to the shaft sleeve and unable to be axially displaced along an output shaft. The peripheral edge of the disc body is embedded into the disc chamber of the movable pulley. The inner conical surface is pressed against the rollers.