Patent ID: 7121304
Filing Date: 2006-10-17
Classification: F16L

Abstract:
1. A hydraulic accumulator comprising: a rigid tank having an open interior; first and second fixtures on said tank for fluid communication with gas and liquid sources exterior to said tank; a flexible bladder, mounted within said tank and having an interior in communication with one of said fixtures, said bladder separating the open interior of the tank into a gas space and a working fluid space respectively communicating through said fixtures; a shut-off valve mounted in a second of said fixtures and movable from an open position to a closed position closing said second fixture, responsive to coming into contact with said bladder when the volume of the working fluid within said accumulator falls to a predetermined low value; and a coil spring attached to said second fixture and external to and surrounding said shut-off valve, said coil spring, upon contact with said bladder, preventing said bladder from being extruded through said shut-off valve and preventing said bladder from contacting the shut-off valve until the volume of the working fluid within said accumulator falls to said predetermined low value.