Patent GB-262702-A (GB)
Title: Improvements in or relating to locking gear for the landing gates of lifts and the like
IPC: B66B13/18
Filed: 1925-09-09
Abstract: 262,702. Waygood-Otis, Ltd., Simmons, T. H. J., and Clemence, E. Sept. 9, 1925. Lift doors, locking and unlocking and operating. -Relates to mechanical interlocking devices for interconnecting the movements for opening the landing and car doors of lifts &c. and for preventing the restarting of the car as long as the door remains open and consists in providing a shaft or the like extending across the doorway and having a partial rotary motion, and positively acting mechanism comprising a vertically displaceable slidable bolt or latch member on the door for retaining it in the set position as long as the door remains open. As adapted for use with a push-button control system each landing door D, Fig. 2, is hung on brackets 10 carrying rollers 11 running on a guide rail 12 and is normally retained in position by a vertically slidable bolt 17 the lower end of which enters a socket in the doorway sill. The upper end of the bolt has a slotted block 27, Fig. 7, engaging the shouldered end 13 of the guide rail and also has an offset arm 28 having a pin and slot connection 29 to a crank-arm 30 slidably mounted on a squared shaft 31 extending across the doorway. A lock-box 34, Figs. 5, 7, is fitted at the side of the doorway into which the shaft 31 passes and within which the shaft carries a cam 36 and an insulating barrel 37. The cam has an oblique face 42 and a cam plate 43 co-operating with a lug 49 on a cranked lever 47 carrying an armature 50 with bevelled horn-pieces 52, Fig. 15, adapted to contact with wedge blocks 55 fitted to magnetic bars 53 with inclined ends. An insulating block 56, Fig. 13, at the bottom of the lock-box carries four spring contact blades 57 adapted to be connected in pairs by bridging segments such as the segments 61 on the barrel 37. The lever 47 has an interrupting pin 66 adapted to displace certain of the contact blades 57 when required. The various contacts are connected in the control circuit of the lift and an electromagnet mounted on the lift cage has pole pieces which at a landing are approximately at the centre of the magnetic bars 53 on the lockbox. In operation, with the cage at rest at a landing, to open the door the handle 20 is moved to give the door bolt its primary movement. This raises the bolt and rocks the shaft 31 until the face 42 of the cam contacts with the lug on the lever 47 and thus limits the movement of the bolt. This rotation of the shaft 31 also completes a circuit for energizing the electromagnet through the contact blades 57. The armature is thus attracted by the electromagnet, rocking the lever 47 so that the pin 66 causes certain of the contact blades to break contact and open the lift operating circuit. This rocking of the lever 47 also moves the lug 49 and releases the cam 36, thus allowing the secondary movement of the handle 20 to completely raise the bolt 17, its lower end leaving the socket and its upper end being free of the shoulder 13. The door can now be opened. In a modification, the shaft is slotted, a projection on the upper end of the bolt engaging the slot to release the door, the contacts in the lock-box and other fittings being modified. A modification adapted for use with a car switch control comprises a squared shaft 245, Fig. 19, on which a cranked arm 244 is slidably mounted, and connected to the offset arm 243 of the bolt 240. The shaft passes into a lock-box 246 and is fitted with the rotary member 247 of a multiple switch in the lift operating circuit, the spring fingers 250 of the switch being mounted on the base of the lock-box.