Abstract: A hydraulic motor receives pressurized fluid from a source controlled by a human operator to convert the energy in the hydraulic fluid to a rotational output to propel a drive wheel of a machine. The hydraulic motor includes an end cover, a manifold, a drive assembly, a wear plate, a housing, and an output assembly. The drive assembly includes a rotor with external teeth and a stator with internal teeth formed by rollers having end faces. The pressurized fluid from the source flows through the manifold to the drive assembly and causes rotational and orbital movement of the rotor relative to the stator. The rotational movement of the rotor is transmitted to the drive wheel by the output assembly. A first set of anti-cogging passages and a second set of anti-cogging passages communicate fluid pressure to the end faces in timed relationship to reduce cogging or detenting of the rotational output of the motor.

Abstract: A hydraulic motor 10 receives pressurized fluid from a source 98 controlled by a human operator to convert the energy in the hydraulic fluid to a rotational output to propel a drive wheel 91 of a machine 90. The hydraulic motor 10 includes an end cover 11, a manifold 12, a drive assembly 13, a wear plate 14, a housing 15, and an output assembly 16. The drive assembly 13 includes a rotor 37 with external teeth and a stator 36 with internal teeth formed by rollers 43 having end faces 49 and 50. The pressurized fluid from the source 98 flows through the manifold 12 to the drive assembly 13 and causes rotational and orbital movement of the rotor 37 relative to the stator 36. The rotational movement of the rotor 37 is transmitted to the drive wheel 91 by the output assembly 16.