Fluid flow control device for steering

Abstract

The present invention provides a device for controlling the flow of a fluid under pressurization within a fluid circuit. [Solution] The device for selectively controlling the flow in a fluid circuit from the first pump 4a and the second pump 4b to the tank via the steering unit 1 and the steering cylinder 5 comprises: a first flow path including a flow direction control device C that prevents the flow of fluid to the first inlet P1 in accordance with the pressure difference at both ends of the flow direction control device C; a second flow path including a control port 33a and an emergency valve 33 for opening a second flow path controlled via the control port 33a; a connection between the first flow path and the second flow path depending on the position of the flow direction control device C between the emergency valve 33 and the first inlet P1; and a connection that responds to the pressure drop between the first pump 4a and the flow direction control device C by opening the second flow path.

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