Abstract:
A pump used in vehicle controlled braking systems provides a reverse direction of flow through a cylinder bore of the pump and utilizes an inlet check valve located outside of the piston at the end of the cylinder bore opposite the piston, in conjunction with an outlet check valve located in an outlet extending through a sidewall of the cylinder bore of the pump. The inlet check valve is assembled and tested as a module prior to being installed in the pump. A fluid reservoir, having a movable wall, is connected to the inlet to facilitate priming the pump module. The piston is driven by a self-supporting drive apparatus with an eccentric element affixed to a stub shaft, or by other forms of a drive apparatus having an eccentric element fixed to a motor drive shaft.
Abstract:
An eccentric-driven piston pump for a vehicle controlled braking system has a pump drive apparatus including a stub shaft having an eccentric journalled in a pump housing for self-supported rotation about a stub shaft axis by a first and a second rotating bearing disposed on opposite axial sides of the eccentric. The stub-shaft is operatively connected to the rotating drive shaft of a motor, and the eccentric is connected for imparting reciprocating motion to the pistons. A pair of thrust bearings including a counterweight for balancing the pump drive apparatus, are disposed on the stub shaft adjacent the eccentric at opposite axial ends thereof between the eccentric and first and second rotating bearings. The motor includes a spherical bearing for alignment of a motor drive shaft with the stub shaft, and a bushing for loosely supporting the drive shaft prior to attaching the drive shaft to the stub shaft.