Geared interface for valve

A valve having a geared actuation mechanism comprising:

• a body having an upper portion and a lower portion;
• a supply port in the lower portion of the body;
• an exhaust port in the lower portion of the body;
• a delivery port in the lower portion of the body;
• a first member having an elliptical surface on a first side of a bisecting line and a semi-circular surface on a second side of the bisecting line, the first member located at the upper portion of the body;
• a second member having a truncated elliptical surface, the second member located at the upper portion of the body, the second member engaging the first member solely at the first member elliptical surface;
• a longitudinal member coupled to the second member and located in the lower portion of the body;
• and
• a biasing member coupled to the longitudinal member;
• wherein the first member is actuated manually to move from a first position to a second position while moving the second member and the longitudinal member linearly thereby opening a passage between the supply port and the delivery port;
• and the biasing member returns the second member and the first member to a first position upon release of the manual actuation, thereby opening a passage between the delivery port and the exhaust port.

A method of actuating a valve with a geared interface comprising:

• manually rotating a first member having a semi-circular surface and an elliptical surface from a first position to a second position;
• matingly engaging a second member having an elliptical surface, wherein the second member moves linearly in response to the manual rotation of the first member and engages the first member solely at the elliptical surface of the first member;
• opening a passage between a supply port and a delivery port as the first member moves from the first position to the second position;
• and
• opening a passage between the delivery port and an exhaust port as the first member moves from the second position to the first position.