Patent GB-365629-A (GB)
Title: Improvements in or relating to electro-pneumatic train control
IPC: B61L3/00
Filed: 1930-10-20
Abstract: 365,629. Distant control of locomotives. IGRANIC ELECTRIC CO., Ltd., 147, Queen Victoria Street, London, and TAYLOR, J. R., Monterey, Uddingston, Glasgow. Oct. 20, 1930, No. 31447. [Class 79 (v).] An electropneumatic train-control system for steam locomotives comprises a steam regulator valve operated by a pneumatic motor and electrically - operated valve mechanism 'arranged to control the supply of compressed air to the motor. The reversing gear is similarly controlled. In the arrangement shown steam is supplied from a boiler B through an emergency stop valve EV to the regulator valve A which is operated by the piston r<4> of a pneumatic cylinder r<5> through a rod r<2>, rack rand pinion r<1>. A contact R<1> carried by the rod r<2> moves over the contacts of a resistance R and indicates, by means of a voltmeter at the control station, the position of the regulator. The reversing lever N<5> is similarly controlled by a piston n<4>. Compressed air can be admitted from a pipe a through solenoid controlled valves v<1> .. v<5> to a cylinder w<2> operating the emergency valve EV and to the cylinders r<5>, n<5> operating the regulator and the reversing gear. There are three controlling points or stations, M<2> on the locomotive, and M<1>, M<3> at the ends of the train, these three stations being connected by an electric cable C to which power is supplied by leads 4, 40. The emergency valve is closed by a weighted lever w<4> and is opened by the power cylinder w<2> when a weighted handle k<1> is raised by hand so as to open the valve a<1> and admit air to the cylinder w<2>. The raising of the handle k<1> closes, the circuit of a solenoid K<1> from line 40 through contact 39, lead 5, one of the safety switches S at one of the control stations, resistance r<10> to line 4. If a breakage occurs in the cable C the circuit of the solenoid K<1> is opened and the emergency valve EV closes. Similarly, if a short-circuit occurs in the cable C the voltage across a relay SCT in parallel with the solenoid K<1> is increased and this relay opens a switch 36a in the solenoid circuit and therefore the valve EV closes. To open the regulator A the controller drum D in one of the controlling stations is moved to bridge the. contacts 1, 4 and thus complete the circuit of solenoid K<3> which opens the valve v<3> admitting air to the left side of cylinder r<5>, so that the rod r<2> is moved to open the regulator. At the same time the contact R<1> moves over the resistance R, this contact being connected through R3, R4 and lead 3 to a voltmeter P at the controlling station which is arranged to indicate the amount of regulator opening. When the regulator has reached the desired position the controller is moved to the neutral position. The rate at which the regulator opens can be controlled by means of a needle valve in the air supply pipe a<3> to the valve v<3>. To close the regulator the controller D is moved in the opposite direction so as to bridge contacts 2, 4 and thus complete the circuit of solenoid K<2> which opens valve v<2> admitting air to the regulator-closing side of the cylinder r<5>. The reversing lever N<5> is operated by means of a controller D<1> which can be moved so as to bridge contacts 4, 6 or contacts 4, 7 and thus complete the circuit either of solenoid K<5> or K<5> controlling the admission of air to the reversing cylinder n<5>. The reversing rod n<2> moves a sliding contact N<1> connected through N3, N<4> and lead 8 to a centre-reading voltmeter P<1>, the other lead 9 of which is connected to the middle of the resistance N.