A
hydraulic accumulator is a
pressure storage reservoir in which a
non-compressible hydraulic fluid is held under pressure by an external source. The external source can be a
spring, a raised
weight, or a compressed
gas. An accumulator enables a hydraulic system to cope with extremes of demand using a less powerful pump, to respond more quickly to a temporary demand, and to smooth out pulsations. It is a type of
energy storage device.