Dual action jack

Abstract

A dual action jack having a hydraulic assembly. Hydraulic assemblies of the inventive subject matter are configured to allow a jack to raise a lifting surface on both the upstroke and down stroke of a jacking lever. Hydraulic assemblies have two pistons that can be compressed to move hydraulic fluid from a reservoir to a ram hydraulic fluid chamber to extend a ram. Each piston has a corresponding check valve assembly that allows hydraulic fluid to flow only along a desired pathway. Additionally, a release valve is provided to release hydraulic fluid from the ram assembly, enabling the ram to return to a resting position.

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