An Improved Signalling Device for use in connection with Colliery Winding Engines.

摘要

118,248. Davies, A. E., and Brown, F. M. April 6, 1918. Order apparatus; mine signalling systems. - An electrically-operated signalling device for use in connexion with colliery winding engines comprises a magnet 1 and a solenoid 2 both in the same circuit which is closed by a switch 4 operated by hand or by the pull rope. A pointer 8 is loosely mounted on a fixed axle 11 and is connected to a ratchet wheel 7 provided with a stop 9 and spring controlled so as normally to bring the stop 9 against a stop 10 on the axle 11. A second solenoid 13 has a core 15 which, when the ratchet wheel 7 is moved by a pawl 6 on a lever 5 attracted by the magnet 1, falls in between the stops 9, 10, and prevents the pointer 8 returning to zero till the solenoid 13 is excited by the closing of its circuit by starting of the engine or by hand. The solenoid 2 has a cross-bar 18 on its plunger 17 which is controlled in its fall by a dash-pot 21. A projection 23 on the cross-bar 18 trips a lever 24 when rising and lifts a retaining pawl 26, and by a pin 27 thereon also the actuating pawl 6, clear of the wheel 7, thus allowing the pointer to fall back to the No. 1 indication. The parts are designed so that, on closing the switch 4, the wheel 7 is moved one tooth before the projection 23 rises to lift the pawls 6, 26, and when this occurs immediately afterwards the core 15 has already fallen to prevent return of the wheel 7 and pointer 8 to zero. Subsequent closings of the switch 4 belonging to the same signal will take place before the projection 23 has time to fall below the trip lever 24, and so are recorded. In the event of the signal not being answered, sufficient time will have elapsed before it is considered necessary to repeat the signal for the projection 23 to fall below the lever 24, and on making the first contact of the repetition the pointer will be released to fall back to the No. 1 position and subsequent contacts will be added on as before. Starting of the engine, or otherwise, excites the solenoid 13 and raises the core 15 and with it a hooked &c. rod 28 which lifts the pawls 6, 26, so allowing the pointer to return to zero. The ratchet wheel 7 may be geared to the pointer 8 to increase the movement of the latter. A series of lamps may be used to give the signal, and rotary contacts are described whereby lamps are successively lit, the earlier ones in the series either being extinguished or remaining lit as the signal proceeds.