Patent GB-756724-A (GB)
Title: Junctions, points, crossings, turnouts, and the like fittings for overhead electric lines
IPC: B60M1/14
Filed: 1952-01-30
Abstract: 756,724. Overhead conductor points. WISEMAN & CO., Ltd., A., and WEBSTER, S. H. Jan. 30, 1953 [Jan. 30, 1952], No. 2452/52. Class 104 (3). An overhead electric line conductor junction has two solenoids mounted on a frog of the fitting and the coil of one solenoid connected to an approach contact closed prior to the vehicle slipper reaching the fitting energizes the corresponding solenoid to turn the tongue from a most used to a temporary position; after the slipper has passed the fitting it engages a departure contact to energize the other solenoid to return the tongue to the most used position. A tongue 1 pivoted to the underside of a frog 2 is swung about its fulcrum 1a by a cam or eccentric 3 rotatable about a pivot 4 attached to the other end of the tongue 1 and passing through a slot 5 in the frog 2. The cam 3 is located between and reacts to move the tongue 1 with two abutments 6, 7 formed on the frogs and is attached through a pin and slot connection with an operating arm 9. The arm 9 is actuated by two solenoids mounted side by side beneath a cover 11, one solenoid being connected to a terminal 23 and the other to a terminal 24. One solenoid actuates through a resilient link 12 an arm 13 of a double arm lever and the other solenoid actuates through a resilient link 15 the other arm 14 of the double arm lever. The arm 9 is subjected to the action of a spring-loaded telescopic link 21 which passes through a dead centre position as the arm 9 moves from one angular position to another. The tongue 1 can be hand-actuated by a lever 20 through a lost motion connection between the double armed lever 13, 14 and a hub 19 of the lever 20 mounted on the pin 10. The lost motion connection is effected by providing a sleeve 9a with two dogs 16, 17 located one on each side of an intermediate arm 18 extending from the hub 19. The arm 18 is normally held in " the middle " position by a spring 22. When a vehicle approaches the junction, assuming the tongue 1 is in its most used position and the vehicle is to travel straight on, then and as a slipper current collector 27 mounted on the vehicle boom 28 is about to ride on to a skate 26 where it is lifted out of contact with the approach line, Fig. 3, the vehicle driver actuates a motor controller 29 to de-energize a motor 30 so that the solenoid connected to the link 12 is not energized and hence the tongue 1 is not moved. If the vehicle is to turn from the most used route the vehicle driver actuates the controller 29 to energize the motor 30 as the slipper reaches the skate 26 and the coil 31 of the solenoid actuating the link 12 is energized to move the tongue 1 from the most used to the temporary position. The vehicle driver again energizes the motor 30 after the slipper 27 leaves the junction and as it rides on to a second skate 25 on the least used leaving line thereby energizing the solenoid actuating the link 15 so as to return the tongue 1 to its most used position. If the driver does not energize the motor 30 as the slipper 27 travels over the skate 25 the tongue 1 will not be returned to its initial most used position and will therefore have to be moved through ropes or chains attached to the lever 20 which through the lever 18 engaging the dog 17 returns the arm 9 and thus the tongue 1 to the most used position. Alternatively two push buttons or switches provided near ground level which momentarily energize the solenoids may be provided in which case the skates will not be necessary. Spring-loaded contacts 32, 33 are used in conjunction with visual indicating means such as coloured lamps to indicate the position of the tongue 1. As shown in Fig. 3 the skate 25 is mounted in the negative line but if the tongue is to be automatically rstored to its most used position without any action by the driver it may be mounted in the positive line. Where switch points are used in two parallel lines the mechanism in one line provided with the solenoids may be connected by rods, for simultaneous operation, to the operating arm of the mechanism without solenoids in the other line. Specification 644,509 is referred to.