Abstract: A windmill pitch driving apparatus is provided, which is capable of achieving improved durability as well as improved output torque and reduced size. The apparatus includes a fixing mechanism for fixing the output pinion to the output shaft. The fixing mechanism includes a positioning portion and a pressure-applying fixing portion. The positioning portion positions the other end side of the pinion with respect to the output shaft side. The pressure-applying fixing portion biases the pinion toward the output shaft in the direction of the axis P of the output shaft from the one end side and is fixed to the output shaft while applying pressure to the pinion.

Abstract: A windmill pitch driving apparatus is provided, which is capable of achieving improved durability as well as improved output torque and reduced size. The apparatus includes a fixing mechanism for fixing the output pinion to the output shaft. The fixing mechanism includes a positioning portion and a pressure-applying fixing portion. The positioning portion positions the other end side of the pinion with respect to the output shaft side. The pressure-applying fixing portion biases the pinion toward the output shaft in the direction of the axis P of the output shaft from the one end side and is fixed to the output shaft while applying pressure to the pinion.

Abstract: A hydraulic circuit for running a crawler vehicle which comprises a running frame portion provided with motors for running the crawler vehicle and an upper swivel portion turnably disposed on the running frame portion via a swivel joint. Electro-magnetic proportional flow directional control valve (a directional control valves) (15) for controlling the running motors are disposed between the swivel joint (41) and the running motors (19). The number of the high pressure passages in the swivel joint (41) can be reduced, because of increase of pressure resistance, the size of the swivel joint can be small, and accordingly, the hydraulic circuit for running a crawler vehicle can be inexpensive, and possibility for leakage of pressure oil becomes low.