Abstract: Embodiments of a directional valve assembly that provides a single device with functionality of a two-position design for automated operation and functionality of a three-position design for manual operation. The embodiments can include a housing with a piston chamber and a spool member that transits in the housing to regulate the flow of a working fluid to a cylinder. The embodiments can also have one or more pilot operators that regulate the flow of pilot air into the piston chamber to move the spool member between two positions, i.e., two open positions. The embodiments can also have a manual operator (e.g., a lever) that can move the spool to the open positions and to a closed position. In one embodiment, the spool member is configured to remain in either a first position, a second position, or a third position in the absence of an outside stimulus on the pilot operators.

Abstract: Embodiments of a directional valve assembly that provides a single device with functionality of a two-position design for automated operation and functionality of a three-position design for manual operation. The embodiments can include a housing with a piston chamber and a spool member that transits in the housing to regulate the flow of a working fluid to a cylinder. The embodiments can also have one or more pilot operators that regulate the flow of pilot air into the piston chamber to move the spool member between two positions, i.e., two open positions. The embodiments can also have a manual operator (e.g., a lever) that can move the spool to the open positions and to a closed position. In one embodiment, the spool member is configured to remain in either a first position, a second position, or a third position in the absence of an outside stimulus on the pilot operators.