Dual hydraulic motor drive system

Abstract

A drive system includes two reversible hydraulic motors connected in parallel to a variable displacement pump and controlled by respective 4-port, 2-position valves. The motors, at least one of which is a variable flow, variable speed motor, are coupled to a single output shaft via an intermediate gear section. The hydraulic motors are positioned on one side of the intermediate gear section and their respective drive shafts are arranged parallel relative to one another. A clutch, which is concentrically disposed within an axial bore of a gear member, is operable to couple the drive shaft of a first of the motors to the output shaft. A second gear member, which is driven by the output shaft of a second of the motors, is adapted to mesh with the first gear member. If both motors are of variable speed construction, it is possible to operate the drive in three speed ranges, i.e. by operation of the first hydraulic motor only, by operation of the second hydraulic motor only, or by simultaneous operation of both hydraulic motors.

Dependencies are inferred from the claim text.