Patent GB-883773-A (GB)
Title: Improvements relating to pantograph collector apparatus
Inventor: AUSTIN CHARLES VALENTINE
IPC: B60L5/18
Filed: 1959-07-21
Abstract: 883,773. Pantograph current collectors. STONE & CO. (DEPTFORD) Ltd., J. July 18, 1960 [July 21, 1959], No. 25015/59. Class 104 (3). In a pantograph current collector comprising a main pantograph 6 provided with a collector 12 having a spread for normal use and an auxiliary collector 7 provided with a collector 13 having a smaller spread than the main collector 12 for use in conditions for insufficient clearance for the main collector in the raised position a trigger is operated, according to the attitude of the collectors, to effect change over from one collector to the other and a preselector determines when the trigger may become effective. In the arrangement shown in Fig. 2, the main pantograph 6 is raised or lowered by a compressed air motor 23 by way of a rod 16 articulated to a lever 17 mounted on a rotatable crossshaft 18 and a rod 15 articulated at one end to a lever 17 and at the other end to a lever 19 mounted on a rockable shaft 20. The auxiliary pantograph 7 is raised or lowered by a compressed air motor 33 through a rod 25 articulated to a lever 27 mounted on a rockable shaft 28 and a rod 24 articulated at one end to a lever 26 mounted on the shaft 28 and a lever 29 mounted on a rockable shaft 30. The apparatus operates in the following manner. On the approach of a vehicle to a low bridge or tunnel with the collector 12 raised and the auxiliary collector 13 lowered and with a change-over valve in a compressed air supply line 34 in the position shown and a control valve (Fig. 1, not shown) operated by a driven in a position to supply compressed air to the main motor 32, a preselector switch 38 is closed by transmission to the switch of a predetermined time sequence of up and down movements caused by providing a suitable configuration of the overhead wire. The main pantograph 12, on being forced by the overhead wire to a predetermined height, moves an extension 41 of the rod 16 to close a trigger switch 39 to complete a circuit to a solenoid 37<SP>1</SP> which changes the setting of a valve 36, to the dotted line position, in order that compressed air is supplied to the motor 33 to raise the auxiliary pantograph 7 and vent the motor 23 through a delayed release valve 37 to lower the main pantograph 6. For the reverse operation, when the auxiliary pantograph reaches a predetermined height, after leaving the bridge or tunnel, an extension 42 of the rod 25 opens a trigger switch 40 to break the circuit to the solenoid 37<SP>1</SP> which allows the change-over valve 36 to return to its original position to supply compressed air to the motor 23, to raise the main pantograph 6, and vent the motor 33 through the delayed release valve 37. The trigger members operating the changeover valve can be operated by pressure fluid or a combination of fluid pressure and electric means and a preselector may be adapted accordingly. Instead of operating the preselector 38 a simple on/off switch manually operated by the driver or an adjustable timing device could be used. Alternatively, the switch could be operated by tripping externally of the vehicle either from a suitable magnet at the side of the track or electronically using a carrier wave or photocell. The switch could also be associated with an indicator light or flasher. Change-over valve 36 may also be operated by two solenoids instead of one. Specifications 866,812 and 882,315 are referred to.