Elastic Hydraulic Accumulator/Reservoir System

Abstract

The invention is a combination accumulator and reservoir which stores energy when the accumulator deforms from its original shape in response to the flow of a pressurized fluid from the reservoir. The stored energy is returned when the fluid flow is reversed and the accumulator discharges the fluid and returns to its original shape. At least one part of the novelty of the invention is that the accumulator and the fluid reservoir reside in the same housing such that the volume of each varies inversely. Accordingly, the invention is more compact and weighs less than conventional accumulators. Another feature of the invention is that fluid is located around the bladder accumulator to lubricate contact between the bladder and sides of the reservoir.

What is claimed is: 
     
         1 . A method of storing strain energy in a fluid based accumulator system, comprising:
 providing a fluid reservoir having a seal attached to the fluid reservoir and an expandable bladder attached to the seal so that the expandable bladder is located within the fluid reservoir;   providing a fluid in the expandable bladder and in the fluid reservoir;   expanding the expandable bladder by pumping the fluid from the fluid reservoir into the expandable bladder;   slidably engaging contact between the expanding bladder and the fluid reservoir, wherein the fluid within the fluid reservoir lubricates such engagement;   releasing the stored strain energy to perform work as the fluid moves through the pump/motor;   receiving the fluid in the fluid reservoir from the expandable bladder as the expandable bladder returns to its non-expanded configuration.