Patent GB-189809330-A (GB)
Title: Improvements in Controllers for Electric Motors.
Inventor: BELFIELD REGINALD
Filed: 1898-04-22
Granted: 1899-03-25
Abstract: 9330. Belfield, R., [Westinghouse Electric and Manufacturing Co.]. April 22. Motors, controlling.-A series-parallel controller, for two series motors on a railway vehicle, is provided with separate regulating and reversing handles,and arranged so that the reversing- handle does not directly actuate the reversing- switch, but only determines the position of parts so that, when the regulating-handle is moved, the reversing- switch is actuated by it. Fig. 3 shows a plan of the mechanical connections between the shafts 3, 4 which respectively carry the regulating and reversing handles. The shaft 4 carries a head with three notches 29, 31, 30, and may be placed so that either of these engages a spring-actuated lever 33. In the middle position shown, another arm of the lever 33 enters a notch in a flange 14 on the regulating-drum 4<b>, preventing any motion of this, and both motors are disconnected. When the shaft 4 is turned in one or other direction, the regulating-drum is freed, and an eccentric pin 25 on the shaft 4 shifts a slider and block 50 so that one of two racks 52, 53 on the block is placed in engagement with a pinion 22 on an aligning shaft, which carries two separate reversers 54 for the two motors. The regulating-shaft 3 carries two cams 18, 19 in engagement with two arms of a lever 47, pivoted at 44<a> and to the block 50. When the shaft 3 is turned in the direction indicated by an arrow, from the position illustrated, the lever 47 and block 50 are moved and turn the reverser shaft so as to close the motor circuits in a direction depending on the lateral position of the block 50. At the same time, the flange 14 locks the lever 33 and shaft 4. The shaft 3 and regulating-drum may then be turned so that seven notches, I to IV, and VIII to X, in it, successively engage a detaining-lever 41. An arrangement of contacts is specified, by which, when the lever 41 engages the notch I, current is supplied to the two motors in series with three resistances. The notches I to I V remove these resistances. During further motion of the regulator two resistances are again placed in circuit, and one motor is cut-out and then joined in parallel with the other, at the notch VIII. The notches IX and X remove the resistances, leaving the motors in parallel. To stop the motors, the regulating-drum is returned to the position illustrated, and may be turned further, oppositely to the arrow. The effect of this is to move the lever 47 and block 50, and reverse the connections of the motors so that they may be used as braking-generators. With the lever 41 in the notch A, the motors are placed in parallel with each other, in a closed circuit of four resistances, connections being made at both ends of the fields ; the resistances may be successively removed, so that by the notch E the parallel motors are short-circuited. The two reversers are secured to their shaft by spring pins, either of which may be withdrawn when it is desired to disconnect one motor, the reverser being then turned so that contacts on it make a connection across it ; in this position, a notch on the reverser receives a spring-actuated lever, another arm of which then stands in the path of a projection on the regulating-drum, so that this cannot be moved to the parallel' connection positions, beyond the notch IV.