Patent GB-905913-A (GB)
Title: Improvements in and relating to means for operating and locking facing points
IPC: E01B7/02
Filed: 1959-08-04
Abstract: 905,913. Operating railway switches. WILLIAMS Ltd., HENRY, and WILLIAMS, O. M. Oct. 28, 1960 [Aug. 4, 1959], No. 26525/59. Class 104 (1). A railway point, provided with a locking member 18 by which the switch blade 11 or 11a for the point is set and locked to its stock rail 10 or 10a, comprises a lever 14 pivotally connected to a bracket 13 secured to a stretcher bar 12 connected to the switch blades 11, 11a, a manually or power-operated rod 15 connected to the lever 14 and a connecting member 16, 16a also pivotally secured to the lever 14 and connected to a crank arm 17 by which the locking member 18 is actuated. and the arrangement is such that when the rod 15 is moved to change the setting of the blades 11, 11 a the lever 14 is pivoted about the bracket 13 so that the locked blade 11 or 11a is released by the operation of the connecting-rod member 16, 16a and thereafter the lever 14 swivels about its pivotal connection to the connecting member 16, 16a so that the stretcher bar 12 is moved to change the setting of the switch blades 11, 11a. In the arrangement shown in Figs. 1 and 2 the switch blade 11a is locked against its stock rail 10a by a notched locking- arm 18 engaging a block 19 attached to the blade 11a. When the blades 11, 11a are to be changed over the rod 15 is moved, manually or by power, towards the stock rail 10 to pivot the lever 14 about the bracket 13 attached to the stretcher bar 12. The lever 14 moves the locking arm 18 out ot engagement with the block 19 attached to the blade 11a and the other locking arm 18 towards the block 19 associated with the blade 11 but since the blade 11 is in the open position the arm 18 associated therewith contacts the block 19 and further movement of the rods 16, 16a is prevented. Since the rods 16, 16a are now held stationary the lever 13 pivots about its connection with the rod 16, 16a to move the blades 11, 11a from one operative position to the other and as soon as the blade 11  abuts its stock rail 10 the rods 16, 16a are able to move to pivot the arm 18 into engagement with the block 19 associated with the blade 11 to lock such blade into its operative position. In the event of the switch being trailed by a train approaching on a track for which the switch is not set the blades 11, 11a are unlocked by depression bars 21 mounted on each of the blades 11, 11a, one only being shown in Fig. 1. The train on approaching the switch, if the switch is not set in the correct position, depresses the bar 21 which, through levers 22, 24, Fig. 2, pivoted lever 26 and rods 28, disengages the appropriate locking arm 18 and block 19 to allow the approaching train to move the blades 11, 11a to the required position. In a modification, Figs. 3, 4 and 5, the switch blades 11 or 11a are operated in a similar manner to the previous embodiment but are locked in the appropriate position by blocks 40 vertically movable by rollers 42, Fig. 5, engaging an inclined portion 38 of cranked arms attached to and movable by links 46 operated in a similar manner to the connecting members 16, 16a of the previous embodiment. The switch in this instance, if in the wrong position, is unlocked when trailed by the wheels of a train depressing a bar or treadle 55 pivotally supported on stools 58 mounted on the sleepers. The bar 55 on being depressed moves, through an arm 60, bell-crank 61 and rod 62, a connecting lever 50 which is connected to the pivoted lever pivotally connected to the bracket 13 on the stretcher bar 12 and the links 46.