GB335570A - Improvements in automatic means for controlling hand-operated locks of railway carriage doors and the like - Google Patents

Abstract

335,570. Gorman, E. C., Green, J. H., and Parry, F. T. June 21, 1929. Electrically-controlled fastenings; latches, preventing operation of; latches, sliding; railwaycarriage doors and the like, fastening automatically; striking-plates for latches.-In automatic means for controlling hand-operated fastenings for railway and other vehicle doors, each lock is fitted with an electromagnet which, when energized during motion of the vehicle, renders the handle inoperative to move the lock bolt. A latch bolt A, Figs. 1, 2, 2A is shot by a spring a<1> and the handle H is urged to corresponding position by a spring c<1>. The handle spindle operates a sleeve-member having an arm with a pin c<2>. Normally, a member B, pivoted at b<1> to the bolt A, rests with its free notched end b<2> in engagement with the pin c<2>, Fig. 2A. Anticlockwise rotation of the handle thus retracts bolt A. An electromagnet D has an armature d<2> with a projection d<4> engaged between pins b<4>, so that when the magnet is energized member B is raised clear of pin c<2> so that movement of the handle does not affect the bolt. Provision may be made to render the handle inoperative non- automatically. for example, a key may be used to operate a switch to close the circuit of magnet D, or to operate a cam raising member B mechanically. The magnets D may be energized when the vehicle is in motion by the provision of generators driven from an axle &c. to supply current, or by the provision of switches closing the magnet circuits through a source of current. Fig. 1 shows suitable circuits in which locks L have magnets D energized in parallel from an accumulator G over a common centrifugally operated switch driven from a wheel axle V. A common lead 3 includes a switch Z normally closed by a spring, and connected by chain K with the usual alarm-signal communication cord on the train so that the magnets D may be de-energized in emergency by pulling the cord. Fig. 10 shows a suitable centrifugally operated switch. A plate adapted to be rotated by a shaft o<6> carries weights W radially guided by ribs r<1> and slots r<2> and urged inwards by springs t<4>. The weights are connected by links T with radial arms of a member I rotatable on shaft o<6> and to which one end of a spring e' is tethered, the other end being connected to an arm E<1> loose on the shaft and provided with a pin e<5> having limited movement along a notch in the edge of switch-arm E. When the device is rotated, weights W move outwards and rotate member I clockwise, causing spring e<3> to pass over the centre of shaft o<6>, whereupon arm E<1> is moved quickly by the spring in anticlockwise direction, pin e<5> moving arm E to bridge contacts e<1>, e<2> with a quick-make action. When the vehicle stops, springs t<4> reverse the above action, giving a quick-break. Circuit connections with contacts e<1>, e<2> are made through carbon brushes and slip-rings, not shown. Fig. 9 shows a striking plate having a safetycatch recess j<2> and locking recess j<1> for co-operation with the latch bolt of the lock.