Gate operator safety system

摘要

An emergency control system for opening or closing a gate resides within a controller for regulating operation of the opening/closing mechanism of the gate. A safety station is in communication with the controller and includes means to signal the emergency control circuit to open or close the gate by using either of two pushbutton switches. Sensing means which detect an unsafe condition in the area of the gate such as human entrapment is connected to the controller and initiates an alarm mode operation of the controller when an unsafe condition is detected and turns on a sound alarm. Pushing either of the safety button switches turns off the sound alarm and moves the gate. Movement of the gate is stopped if the pressed button is released while the gate is in motion which otherwise continues to its limit. The emergency control circuit is responsive to input signals from the safety station only when the controller is in the alarm mode.