Hydraulic fuse with pressure regulator

Abstract

A hydraulic fuse monitors the quantity of hydraulic fluid passing through the fuse, and then blocks such flow when a selected quantity of fluid has passed through the fuse which includes: a body structure containing cavity structure; a primary piston in the cavity structure and movable endwise to control fluid flow through a first port; a sleeve, and a slider in the cavity structure, and in the path of fluid flow toward the primary piston; the sleeve and slider being coaxially relatively axially movable, and there being a regulator spring acting to urge the sleeve in one axial direction; and fluid flow control slots formed by the sleeve and slider to control flow both to the piston for controllably displacing same, and to the first port, and characterized in that as the forward flow rate through the fuse reaches a threshold, the piston begins its movement toward the port, and as the flow rate increases above the threshold, relative axial movement between the sleeve and slider acts to maintain nearly constant the fluid pressure drop across primary slot means included with the control slots, and to controllably meter fluid flow to the piston via metering slot means included within the control slots, for displacing the first piston as aforesaid; whereby the piston is displaced to close the first port after a required quantity of fluid has passed through the fuse.