Abstract: A ring cone type stepless transmission for effecting change speed on a torque received from an input section and transmitting the torque to an output section. The transmission comprises a main shaft for rotatably supporting a carrier which rotatably supports a plurality of taper cones. The main shaft further supports a disk-shaped rotatable member spring-loaded for contacting the taper cones to effect torque transmission therewith. A ring-shaped change speed member is provided movable parallel to the main shaft to contact varied positions of the taper cones, thereby varying a transmission ratio between the carrier and rotatable member. A supporting member is also mounted on the main shaft for contacting and supporting the taper cones. This supporting member counteracts a moment acting on the taper cones as a result of contact pressures applied to the taper cones from the rotatable member and change speed member.

Abstract: A transmission for a tractor in which a main shaft to receive engine power, a travelling speed change shaft and a PTO speed change shaft are disposed in parallel with one another. A first travelling speed change means of a hydraulic clutch type is disposed on the travelling speed change shaft and provided with clutch means for backward travelling and first-stage forward travelling. A second travelling speed change means of a hydraulic clutch type is connected to and disposed rearwardly of the main shaft and provided with clutch means for second-stage, third-stage and fourth-stage forward travelling. The second hydraulic clutch type travelling speed change means is so constructed that, in response to power input from the main shaft, the clutch function thereof is performed prior to the speed change function thereof.