GB190306368A - Improvements in Brake Apparatus for Electrically Propelled Railway and Tramway Vehicles. - Google Patents

Abstract

6368. Newell, F. C. April 1, A.D. 1902, [date applied for under Patents Act, A.D. 1901]. Electric locomotives and motor vehicles. - Relates to electric braking systems for electrically-propelled railway and tramway vehicles, particularly those systems in which the motors are utilized as generators in local braking circuits, and consists in providing the brake switch with a blow-out magnet having coils through which the full current flows and with an increased number of resistance points to divide the resistance into a number of small steps to enable the brake to be applied and released more smoothly ; also in arranging the circuit connections so that leakage from the electromagnets in the braking circuits is avoided. This is effected by connecting one end of the brake magnet coils and also the resistance bars on the braking-switch, to the ground. The diagram, Fig. 1, shows the braking-switch 2 and circuit connections applied to an ordinary car equipment of two motors 33, 34 and a running-controller 3, the braking-switch being shown in its first braking-position. The braking- current from the generators 33, 34 flows to the bars of the reversing-switch 19 and braking-switch 2 and then through the resistance 41, and to ground at 44, thence passing through the brake magnet coils 45, the fields of the motors, the blowout magnet coils 4, 5, and connections back to the armatures. Further movement of the braking- switch varies the amount of resistance by bring- ing the contact bars 61, 62, 63 ... 67 into contact with their respective fingers 68, 69 ... 76. All the resistance-controlling bars, and also the bar 781, which is connected to the field outlet lead 55 in the running position, are grounded directly on the base of the braking-switch. When the brake switch is in the running-position, as shown in Fig. 2, and the running-controller is moved to its first series position, the current flows from the trolley 32 through bars of the brake switch to the running-controller and thence through the various connections to the resistance 41, motor 33, motor field, blow-out magnet coil 4, motor 34, motor field, blow-out magnet coil 5, bar 781 of braking-switch to ground at 44. When the motors are running in parallel, the current flows to the bars on the running-controller and thence through the resistance 41, after which it divides and passes through both motors 33, 34, motor fields, and coils 4, 5 of the blow-out magnet to ground at 44. The resistance 41 is shown divided into ten divisions for controlling the brake circuit and four divisions for the running-circuits, but any other number of divisions may be used.