Patent GB-190519989-A (GB)
Title: Improvements in Apparatus for Electrically Operating Railway Carriage or like Doors, and for Operating Locks in connection therewith.
Inventor: CRAVEN ALFRED
Filed: 1905-10-03
Granted: 1906-05-03
Abstract: 19,989. Craven, A, Oct. 3. Door opening and closing apparatus. -In one arrangement, shown in plan in Fig. 2, hinged doors 4 at the ends are opened or closed by an endless cord 2 and electro-magnets 1, the cord being connected to the door by chains and sprocket - wheels. When the doors are shut, they are locked by catches 54, 54<a>, which are released by electromagnets under the control of the same switch as that which controls the opening and closing of the doors. In another arrangement, shown in Fig. 6, a central sliding door 21 is operated by an electric motor 22, the shaft of which has a pinion engaging a rack on the top of the door, and the hinged doors at the ends are operated by an endless cord 2 carrying a stop 27, which is engaged by projections 25, 26 on the door 21. The door 21 at the end of its travel operates switches 29, 29<a> which put into action an electro-magnetic switch for cutting out the motor. The electromagnets 1, Fig. 2, consist of two pairs of coils 5, 6, 7, 8, Fig. 3, each pair having a fixed core 10 in one coil, pole-pieces 9, 11, and a brass tube 12 in the other coil which forms a guide for a movable core 13, to the ends of which are attached the cord 2 for operating the doors. The tube 12 is made to project slightly through the pole-piece 11 in order to lessen the liability of the core 13 to stick, and a piece of brass tube 15 is fitted at the other end for the same purpose. The wire is secured to the core 13 by passing its end through a short piece of brass tube, knotting it, and screwing the tube into the core. The core 13 is moved in one direction or the other according to which pair of coils is energized. The switch consists of a bar 90, Fig. 14, adapted to be moved on to contacts 88, 89 for energizing the door-operating magnets and on to a contact 87 for releasing the door catches. Springs normally hold the bar 90 in a central position. The switches 29, 29<a>, Fig. 6, consist each of a lever 31, Fig. 19, m wed in one direction by a spring 36 and. in the other by a push-button to close a mercury contact 35. This completes a circuit torough a coil 46, Fig. 13, which then draws up a core 45 against the action of a spring 53 and lifts a carbon contact 43 out of a mercury well 39, thereby breaking the circuit through the door-operating motor. The contact 43 is screwed to an insulating-piston 40 and also to a copper rod 42 enclosed in an insulating-tube 41 which connects the piston 40 to the core 45. The rod 42 is connected to a wire through an aperture 44<a>. The mercury is contained in a brass receptacle 38 enclosed in an insulating - casing 37. Brackets 48, 50 and clips 51, 52 support the coil and switch. In a modification, a lever is interposed in the connexion between the core and the switch. The switch for controlling the doors shown in Fig. 6 and their locks consists of two insulated copper bars 72, 73, Fig. 16, mounted on a sliding bar m a casing 75 and fitted with insulating-blocks so as to operate in conjunction with brushes 76, 76<a>, 77,77<a>, 78, 78<a> to open and close the required circuits. The switch is operated by a handle 79, which is acted upon by springs to keep it in a central position. The lock consists of a spring bolt 63, Fig. 9, the stem 62 of which is acted upon by an electro-magnet consisting of coils wound round bobbins 60, 61 enclosing cores 57, 58. Pole-pieces 56, 59 complete the magnetic circuit. A ring of non-magnetic material 65 in the pole-piece 59 prevents the stem 62 from sticking. The bolt can be drawn back by band by means of a spindle 70 fitted with an arm 69 for engaging a pin 68 projecting from the bolt.