Patent GB-190303620-A (GB)
Title: Improvements in Apparatus for Lighting Railway Trains and for like purposes.
Inventor: ELROY JAMES FINNEY MC
Filed: 1903-02-16
Granted: 1904-04-16
Abstract: 3620. McElroy, J. F. Feb. 16. Casings; dynamos, driving; dynamos, regulating. -Relates to systems in which a railway vehicle is lighted by the current supplied from a dynamo driven by an axle, storage batteries supplying the circuit when the train is at rest or running slowly, and the apparatus being also applicable for other purposes. Fig. 1 is a diagram showing the general arrangement, which is a modification of that described in Specification No. 1095, A.D. 1903. Fig. 1<a> shows the connections when the dynamo A is cut out, the battery B supplying the lamps L. When the dynamo A is cut-in by the automatic switch D, the switch arm P is also automatically operated, and takes up the position shown in Fig. 1<b>, with the battery in parallel with the lamps, which are supplied through a resistance R, the resistance R<3> being cut out. The switching-apparatus and regulating-apparatus are controlled by means of a potential magnet E, Fig. 1, the fine coil e<1> of which is connected between the points 4, 5 across the dynamo terminals. When the speed of the train is sufficient, the core F is drawn in, operating a lever K<1> and closing the circuit of a small motor M which operates the regulating-switch S. The switch D is carried by an arm K, and is held open by a pin Z fitted on a moving part of the regulating-switch S. On the first movement of this switch S the switch D closes, and the generator A is connected to the circuit. The arm P continues to move, cutting out the resistance R, Fig. 1<a>, and putting in the resistance R (R<1>, R<2> of Fig. 1) in the lamp circuit. The tension of the spring S' connected to the core F is varied by a cam C so that it will have the proper effect when the switch P is fully on and serving as a regulator only. With changes in the potential the contact G touches either G<1> or G<2>, the motor M rotating to cut the regulating-resistance R<4> in or out of the field coils of the generator A. The contact G<2> is carried by a pivoted lever K<2>, and is moved away by the pin Z to prevent the battery circuit through the motor M from being closed when the switch is in the ' off ' position. A coil e<2> in series with the battery may also be arranged on the magnet E, and prevents an undue flow of current through the battery when it is exhausted. To prevent the motor M from rotating too rapidly, it may be fitted with a centrifugal circuit breaker H. In a modified arrangement, the main switch D is controlled by a separate magnet, and is fitted with a projection adapted to interlock with the core of the magnet E and prevent any movement of the regulator when the switch is open. Electromagnetic regulators may be placed in the lamp circuit to vary the resistance and maintain a constant potential, in addition to the regulator for the dynamo. In another modification, Fig. 2<a>, the potential magnet E controlling the contact G &c. is arranged to act in connection with a coil E<3> arranged in series with the lamps L. Or, in place of the coil E<3>, separate coils in series with each group of lamps may regulate the tension of the spring S<1>. Fig. 3 shows the method of mounting the dynamo. It is provided with a casing formed in two parts hinged together. The shaft A' is journalled in the casing, which rests on springs V, supported on bars W suspended by links X<1>. The casing has projecting arms A<2>, fitted with a half-sleeve T' resting on the axle T. The lower half of the sleeve is applied from below, and secured by bolts. The inner ends of the bars W rest on or are secured to the sleeve. A hook X limits the play of the machine, and a grease box t<1> is provided.