Hydraulic cylinder assembly

Abstract

A hydraulic cylinder assembly comprising: a single-acting hydraulic cylinder; an oil tank; a fluid line fluidically connecting the oil tank with the hydraulic cylinder; and a motor unit comprising a pump disposed in the fluid line and comprising a motor configured to operate the pump to pump fluid from the oil tank to the hydraulic cylinder to extend the hydraulic cylinder, and to permit flow of fluid from the hydraulic cylinder to the oil tank through the pump during retraction of the hydraulic cylinder, a pressure sensor configured to output a pressure signal indicative of pressure of hydraulic fluid in the hydraulic cylinder; and a controller configured to control the motor unit based on pressure signals received from the pressure sensor. The hydraulic cylinder assembly is configured so that oil leaving the hydraulic cylinder, during retraction of the hydraulic cylinder, passes through the pump to the oil tank.

Dependencies are inferred from the claim text.