A spring-loaded accumulator is similar to the weight-loaded type except that the piston is preloaded with a spring. A typical cross-section of this type of accumulator has been illustrated in Figure 7.15.
The spring is a source of energy, acting against the piston and forcing the fluid into the hydrauhc system. The pressure generated by this accumulator depends on the size and preloading of the spring. In addition, the pressure exerted on the fluid is not constant. They typically deliver small volumes of oil at low pressures and therefore tend to be heavy and large for high-pressure, large volume systems.
A spring-loaded accumulator should not be used for applications requiring high cycle rates as the spring may lose its elasticity and render the accumulator useless.