Abstract: A detection system for detecting a body near a doorway includes two detectors having one or more activation lines that overlap each other. With certain mounting arrangements, the detectors cover areas within and on both sides of the doorway. The detectors are meant to help prevent an already open door from accidentally closing on the body. The door is powered by a drive unit that ignores the detectors when the door is closed.

Abstract: A door system includes an antenna-based proximity sensor with a releasable electrical connector that enables the sensor to function with a breakaway feature of the door. The sensor includes a signal generator and a door-mounted antenna for sensing a body or an obstruction near the door. The signal generator (or oscillator) can be installed at various locations between a power source and the antenna. In some cases, the wiring between the antenna and the power source includes a rotatable feature to accommodate the rotation of a drum that carries a wrap-up, pliable door panel. The rotatable feature may be a rotatable electrical connector, or it may be a wire having sufficient length and flexibility to twist about itself within the hollow interior of the drum.

Abstract: A method for recognizing potential faults of one or more remote body detectors of a door can be applied to a wide variety of conventional detectors that may not necessarily have a self-monitoring feature themselves. The method may be counter-based, timer-based or a combination of the two. In some embodiments, the method involves comparing the behavior of a detector to that of another detector at the door or to the activity of another door-related event, such as the door opening or closing. In some cases, the activity of a single detector is compared to a predetermined acceptable range of activity over a given period.

Abstract: A detection system for detecting a body near a doorway includes two detectors having one or more activation lines that overlap each other. With certain mounting arrangements, the detectors cover areas within and on both sides of the doorway. The detectors are meant to help prevent an already open door from accidentally closing on the body. The door is powered by a drive unit that ignores the detectors when the door is closed.