| 摘要 |
459,640. Master control of D.C. motors; actuating controllers. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London. May 16, 1936, No. 13911. Convention date, May 17, 1935. Addition to 458,390. [Class 38 (iii)] Combination of resistances.- In a series-parallel control system, each motor 10, 13, Fig. 1, is provided with resistances 49, 50, controlled in accordance with the parent Specification, and additional control means are provided for connecting each motor in series with its controlled resistance both for the series and parallel accelerating stages. Upon operation of a controller 18, Fig. 3, to a " parallel " position, a self-maintaining relay I is energized to energize a solenoid 28 which actautes a controller 21. This controller closes switches 1, 2, 3, 9, Fig. 1, to connect the motors 10, 13, in series across the supply, and in series with the resistances 49, 50, and an additional resistance 49a. The controller then closes switches 6, 4, 8, 5 and 7 in turn first to cut out resistance 49a and then to eliminate one half of each of the resistances 49, 50, in steps. This completes the movement of the controller in one direction and the circuit of a relay II, prepared by the relay I, is completed. The relay II deenergizes the relay T, and the solenoid 28 is de-energized, with the result that the controller 21 is returned by a device such as a spring. Due to the operation of the relay II, and the de-energization of the relay I, the motors 10, 13, are connected in series with the adjustable parts of the resistances 49, 50, only, and during the return movement of the controller the switches 3-9 are operated again but in the reverse order, and the adjustable parts of the resistances 49, 50, are eliminated in steps. The controller returns to its initial position at which the motors are connected in series directly across the supply, and then a switch 22 is reclosed to energize a relay IIIa/b which de-energizes the relay II and effects parallel connection of the motors each in series with its own resistance 49, 50. These resistances are again eliminated as during the series stage by a forward movement of the controller effected by the solenoid 28, and a spring return movement. Thus the motors are finally connected in parallel directly across the supply. The movements of the controller 21 are regulated by a valve 35 in a liquid system operated on by pistons 33, 34, geared to the controller, and the valve is adjusted by a coil 37 carrying the motor current. The controller 18 has a " shunting " position in which the motors are connected in series across the supply and in series with resistances 49, 49a and 50, and a " series " position which limits the acceleration to the series stage.
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