Hydrostatic drive for road vehicles - has control valves in block for different combinations of four pumps giving fifteen output speeds

摘要

The hydrostatic drive (1) consists of a hydraulic motor (9) housed in a block (2) and four pumps (5-8) mounted on a common base plate (3). The four pumps are each of a different capacity and are driven from the engine by one shaft (10). The pumps are connected by supply and return pipes (4) to the motor (9) which drives the output shaft (11). The control valves (12) are operated by a lever and are so arranged that for a given position of the lever any one or any combination of the four pumps is connected to the motor. It is thus possible to arrange for fifteen different rates of fluid flow resulting in fifteen different speeds of the hydraulic motor.