This invention is a radial trunk piston oil pump or oil motor with rotary hull. Its overall efficiency, is up to 95%, and mechanical efficiency up to 97%. The speed of rotation is 0~100 r.m.p. (1500~2000 r.p.m. in a short time), It is small in size, light in weight, simple in structure (only five fixed main spare parts) easy to make, and has no special requirements for material and using oil. It is insensitive to environment factor. It can endure intense impact and vibration when the vehicle drives on the rough ground. It can be installed into the wheel to drive it, simplify the drive system, facilitate the arrange of vehicles and realize infinitely variable speeds. It is especially fit to use this device in all vehicles as a drive set. |