GB191015831A - Improvements in and relating to Railway Signal Operating amd Controlling Apparatus. - Google Patents

Abstract

15,831. McKenzie & Holland, and Pearce, W. A. July 1. Visual outdoor signals; slots, reversers, and like apparatus.-Apparatus for controlling and operating semaphore signals in which an electro-magnetic clutch and a motor are employed is provided with a quick-acting switch in the motor circuit and a brake for the motor, which are operated simultaneously. A dash - pot is provided to absorb shock as the signal moves to danger by gravity. The motor 1 drives the wheel 2 through reduction gear. The wheel 2 carries a number of studs 10 which engage a pawl 16 pivoted on a disk 11. This pawl 16 is rigid with the arm 18, which may be held in the position shown by the lever 15 connected to the armature 13 when the clutch-magnet 12 is energized. If the magnet is de-energized, the pawl is turned about its pivot by the studs 10, and does not move the disk 11 on the signal, which is either mounted on the spindle 8 or is operated by a rod attached to a crank on the spindle. If the magnet is energized when the motor drives the disk 2, the disk 11 is moved until the projection 37 meets the arm 36. This lifts the member 34 and opens the switch contacts in the motor circuit, and applies the brake block 25 to the disk 26. The quick-acting switch is held closed normally by the arm 28 engaging a projection on the lever 29. The levers 29, 22 are acted on by a compression spring 33 and a tension spring 31, which are caused to exert greater forces just before the latch is removed so as to move the switch member 20 quickly. The switch is closed and the brake removed as the signal arm returns to danger by a projection 38 engaging the arm 36. The part 34<a> of the member 34 draws down the arm 22, compressing the spring 33 and extending the spring 31 until the catch 28 engages the latch on the lever 29. A dash-pot, of which the piston is connected to the arm 41, absorbs shock as the signal arm moves to danger.