Car park barrier safety device - has delay device to reverse drive motor when barrier arm encounters obstacle

摘要

A barrier which can be lowered to prevent e.g. a vehicle from passing a stopping point, suitable for a car park, has a safety device which raises the barrier again if it meets an obstacle when lowered. The drive shaft of the motor (5) rotates an arm (4) with a spindle projecting from it, which passes through a slot (7) along the barrier arm (3). The drive shaft rotates this spindle through an angle of 270 deg., and the spindle slides in the slot so as to swing the barrier arm from the vertical to the horizontal position, i.e. through 90 deg.. The motor is fitted with a delay device which reverses the drive after a given time so that the motor is protected against overheating.