Double valve with anti-tiedown capability

摘要

A control valve system has two valve trains each of which has a series of valves which dynamically move between a deactuated position and an actuated position. An inlet of the valve system is connected to an outlet of the valve system when all of the valves are actuated and the outlet of the valve system is connected to an exhaust when all of the valves are deactuated. Each valve train includes a solenoid valve which when actuated moves the remaining valve members to their actuated position. The various valves of each valve train are interconnected with the valve of the other valve train such that actuation of all of the valves in a substantially simultaneous manner will connect the inlet of the valve system to the outlet of the valve system and deactuation of all of the valves in a substantially simultaneous manner will connect the outlet to the exhaust. The valve system monitors the dynamic movement of the valve members during its operation will move to a locked out condition when any valve is in a deactuated position and when one other valve is in an actuated position. In the locked out condition, the outlet of the valve system is corrected to the exhaust. The valve system will remain in this locker out condition until a resetting operation is performed. During a reset operation, the valve system can not actuate one of the valve trains because one of the valve trains is depressurized during the reset operation.