US Patent 7828353 Refuse tipper latching device and method

Slidably mounted within the cylinder 108 of the accumulator 46 is a piston 48. A spring 50 is positioned behind the piston 48, which biases the piston 48 toward port 56. The portion of the cylinder 108 occupied by spring 50 is vented to the atmosphere by breather 52, which allows air to pass in and out of cylinder 108. As a result of the spring 50 acting on the piston 48, fluid is collected, stored, and released from the cylinder 108 under pressure. It should be understood that the accumulator could collect, store and release fluid under pressure using energy storage devices other than spring 50. For example, the accumulator 46 could be gas.