Automatic control circuit for compressed air operated doors - uses door valve controlled by transistors and thyristors as operational circuit elements

摘要

The automatic system for control of compressed air operated doors has a logic circuit. Associated with the logic circuit is a central control circuit which controls the door valve. This door valve opens a door or doors when an opening order is actuated by a passenger and the door control is relased by the driver. A similar procedure is used for door closing, except that there is an opening maintenance time period for certain doors. In addition to the logic circuit, the central control circuit includes all the non-peripheral functional elements of the automatic system. These elements include switching, memorising, timing and combination circuits. The functional elements being fabricated according to discrete semiconductor techniques. The door valve is controlled by transistors and thyristors are used as functional elements. These thyristors are used as AND gates and or high power memories.