GB178398A - Improvements in control mechanism for motor actuated doors - Google Patents

Abstract

178,398. National Pneumatic Co., (Assignees of Hedley, F., and Doyle, J. S.). April 11, 1921, [Convention date]. Operating doors electrically and pneumatically.-A sliding door of a vehicle is provided with a yielding buffer on its front edge which contains a pair of normally-separated contact members forming part of the circuit of the door-closing control magnet of the motor whereby, when an obstruction is encountered, the contacts are forced into engagement and the action of the motor is reversed to open the door. The door 1 is operated by a pneumatic motor 2 through a rocking-arm 3, and it is controlled by opening and closing electromagnetically-operated valves 5, 6. The front edge of the door carries a buffer member 7 enclosing a rubber or other flexible tube 11 containing a coiled spring 12 and an axially-positioned rod 14. These members 12, 14 are permanently connected through wires 13, 15 with conducting rods 10, 9 carried by the door and engaging members 20, 21 respectively leading to the magnet control valves 5, 6. When the door in closing meets an obstruction, such as a passenger, the contacts 12, 14 are forced into engagement and the circuit of the magnet valve 5 is completed, to reverse the action of the motor. Instead of, or in addition to the members 12, 14 the member 11 may carry a contact 50 adapted to bridge the contacts 51, 52 connected with the members 9, 10, when the obstruction is encountered. As shown in Fig. 1, the contacts 9, 10 and 21, 20 are out of engagement when the door is fully closed.