Abstract: A transmission for a tractor comprising a power takeoff line change speed gear mechanism, propelling line change speed gear mechanisms and a backward and forward drive switching mechanism. The propelling line change speed gear mechanisms include a main change speed mechanism, an auxiliary change speed mechanism and a front wheel change speed mechanism. The power takeoff line change speed mechanism, and the main and auxiliary change speed mechanisms somewhat encircle a longitudinal center line transversely of the transmission. The backward and forward drive switching mechanism and the front wheel change speed mechansim are juxtaposed in a region immediately forwardly of the change speed machanisms B, C and E.

Abstract: PTO-driving of a double-clutch-incorporated type transmission characterized in that the PTO-driving comprises a first gearing mechanism interlocking with a PTO main shaft, a second gearing mechanism interlocking with a running-travel main shaft, and a coupling means functioning to selectively drivably couple the said gearing mechanisms with a PTO transmission shaft.

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.

Abstract: A gear transmission comprising a driving transmission shaft, a driven transmission shaft, a gear shaft between the two transmission shafts, three speed change gears of different diameters mounted on the gear shaft, an auxiliary speed change shaft carrying three gears of different diameters respectively in mesh with the speed change gears, and two clutch members provided between one or the other of the transmission shafts and the gear shaft. Each clutch member provides two speeds by switching between a position to connect one of the transmission shafts to the gear shaft and a position to connect the transmission shaft to one of the speed change gears. Thus the gear transmission provides a total of four speeds.

Abstract: A transmission mechanism for vehicles comprising main clutch means having a primary clutch and a secondary clutch, primary and secondary propeller shafts for primary and secondary transmissions adapted to be intermittently rotated by the operation of said main clutch means, a first transmission system adapted to transmit the transmission power of said primary propeller shaft, a second transmission system adapted to transmit the transmission power of said secondary propeller shaft, and a reduction gearing for interlocking said secondary propeller shaft with said second transmission system. Further disposed is a transmission unit having a uni-directional clutch adapted to permit engine power to be transmitted only in the direction from said secondary propeller shaft to said primary propeller shaft.