piston pump

[img_assist|nid=11990|title=|desc=|link=none|align=right|width=165|height=187]Piston pumps, as used in hydraulic systems, create a flow by pistons moving in and out of cylinder bores as the latter pass over inlet and outlet ports. The stroke is imparted to the pistons either by having the cylinder barrel set at an angle to the drive shaft or by means of a swashplate mounted on the drive shaft.