Patent GB-862757-A (GB)
Title: Improvements in and relating to automatic electrical speed changing control means for railway vehicles
Inventor: RAWLINS BERNARD GEORGE
IPC: B60L15/34
Filed: 1958-07-29
Abstract: 862,757. Change-speed control. SELF-CHANGING GEARS Ltd. July 28, 1959 [July 29, 1958], No. 24369/58. Class 80 (2). A change-speed gear for railway vehicles or rail cars of the kind including two or more coupled vehicles, one or more of which may be power vehicles controllable from either end of the group of vehicles, in which gear-changing occurs automatically in response to vehicle speed and in which electrical means are operative at each gear change for closing the throttle of the power unit or units, is provided with relays AP, TC controlling operation of the gear change and throttle controlling circuits respectively. The arrangement is a modification of that shown in Fig. 1 of Specification 802,272 and reduces the number of wires running the entire length of the train. As applied to a changespeed gear for a rail car having a power car and a trailer car, electric speed-responsive relays IP ... 4P are progressively energized by vehicle-driven generators 1, 2 and control relays IS ... 4S which in turn control gear-changing, as described in Specification 802,272. Driver's control stations 10, 10a are provided in the power and the trailer cars and each station includes a forward and reverse control-switch 15, a drive control switch A and a throttle control switch 16. After the direction of travel has been selected by the switch 15 the vehicle can be controlled by the switches A, 16. Each switch A has neutral (N), D1 and D2 positions. In position D1normal automatic gear-changing occurs; contacts 8, 9 of the switch A are closed to complete a circuit from a positive supply line 6a, a coil AP<SP>1</SP> of the relay AP, a line 7 which extends between the contacts 8 of the switches A at the two control stations, the contacts 8, 9 of the actuated switch, a line 11 and the associated relay TC to a negative supply line 12. Energization of relay AP closes switches CAP, one of which energizes a relay AS closing switches CAS in the lines to wires TG2 ... TG4 corresponding to the second, third and fourth gears, and energization of relay TC closes a switch CTC to provide a current supply to the throttle control switch 16 so that the throttle can now be controlled. At each gear change a relay DP is momentarily energized by a condenser discharge circuit 13, and momentarily opens a contact CDP, breaking the circuit to the throttle relay TC so. that the throttle is momentarily closed. Switch CDP is mechanically connected to a switch K which closes just before CDP opens so that relay AP remains energized due to a second coil AP<SP>11</SP> since switches K, CAP are closed, thus permitting gear changing. In the D2 position of switch A a circuit is completed from the line 6a, coil AP<SP>1</SP> and relay G in parallel, and contacts 8, 18 to the line 12. The relay TC is shorted out and energization of relay G introduces resistances G2 ... G4 into the circuits of the speed-responsive relays 2P ... 4P to prevent their energization so that the transmission is held in first gear.