TWO-STAGE HYDRAULIC PISTON PUMP

摘要

TWO-STAGE HYDRAULIC PISTON PUMP A two stage piston pump has serially arranged pump chambers each having an input passage and a delivery passage. The first stage has a larger displacement than the second stage such that complete filling of the second stage is attained. The piston of the first stage is reciprocated through the cooperation of a spring and a selectively energizable solenoid coil. The piston of the second stage is secured to and reciprocable with the first stage piston. The cylinder for the second stage has an overflow passage disposed to ensure that all the fluid discharged from the first stage prior to the second stage piston closing the overflow passage passes through the second stage cylinder.