Patent ID: 9322419
Filing Date: 2016-04-26
CPC Classification: F01L,F15B,F16K,Y10T

Claim Text:
1. A central valve for a pivot motor actuator, the central valve comprising: a housing tube including a first operating connection, a supply connection, a second operating connection and a tank drain connection; a piston enveloped by the housing tube and moveable relative to the housing tube, wherein the first operating connection is formed by at least one first radial recess and the second operating connection is formed by at least one second radial recess, wherein the at least one first radial recess is arranged at a first axial distance from a first end of the housing tube and the at least one second radial recess is arranged at a second axial distance from the first end of the housing tube, wherein the first axial distance is different from the second axial distance, wherein the first operating connection is connected with the supply connection and the second operating connection is connected with the tank drain connection in a first position of the piston, wherein the piston is positioned in a center in a second position of the piston, and wherein the second operating connection is connected with the supply connection and the first operating connection is connected with the tank drain connection in a third position of the piston, wherein the piston includes at least one first check valve on its outside, wherein the at least one first check valve opens a flow path from the first operating connection to the second operating connection between an outside of the piston and an inside of the housing tube when the piston is in its third position and the first operating connection is provided with a pressure which exceeds a first threshold value.