ELECTRIC LATCH RETRACTION DEVICE FOR VERTICAL ROD DOOR LATCHES

摘要

An electric latch retraction device for vertical rod door latches includes an automatic adjustment feature including a limit switch and a linear sensor, such as a Hall effect sensor, which detects vertical position. A microcontroller monitors the vertical position of a pivoting retraction lever driven at the pivot by a linear driver. The housing for the electric latch retraction device is preferably external to the door and one end of the retraction lever extends into the door to drive a vertical rod door latch mechanism while an opposed end contacts the limit switch to signal that continued driving of the linear driver will begin to drive the vertical rod door latch. The microcontroller determines from the vertical position of the retraction lever when the limit switch is actuated whether the electric latch retraction device is mounted too high or too low.