System for protection against getting caught in automatically operable doors or windows, particularly of vehicles

摘要

A system for protection against getting caught in automatically operable doors or windows, particularly of vehicles. Specific intervals of time within which the closing or opening door should reach a given position are preset. When the door does not reach one of these positions within the time allowed, the reversing motion is initiated or the cycle of motions is stopped. For this purpose, an electric signal generator coupled to the door motion delivers electric position signals when predetermined positions of the door are reached. An electric storage element is set by the position signals and after a predetermined time interval automatically reset, with the logic value of its output signal changing. The output signal of the storage element and an extreme-position signal produced by limit switches coupled to the door are fed to a logic circuit which delivers a control signal when the output signal of the storage element has the value occurring upon the latter's being reset and the extreme-position signal has the value corresponding to an intermediate position of the door. The control signal is fed to a mechanism for stopping or reversing the door motion.