Pneumatic door lock thumb turn device for remote control of door lock

摘要

To modify a door lock into a remotely controllable structure by air pressure without changing the door lock structure in place of a thumb-turn provided on an outer surface of a door plate of a conventional door lock.SOLUTION: A pneumatic source is connected in parallel to an input port of a pneumatic switch and an input port of a switching valve, and a pneumatic cylinder connected to the switching valve is connected to a thumb-turn shaft connected to a thumb-turn knob. The pneumatic cylinder is driven by the driving pneumatic pressure output from the switching valve due to a change in the control pneumatic pressure from the pneumatic switch which has sensed a change in the open/closed state of the door. The thumb-turn shaft is axially rotated by driving of the pneumatic cylinder. Also provided is a door lock remote control thumb-turn device which is configured to be capable of reversing against the stress applied to the pneumatic cylinder by manually rotating the thumb-turn knob from the state in which the shaft is rotated.SELECTED DRAWING: Figure 1