Patent GB-190626985-A (GB)
Title: Improvements in Locking Frames for Operating Electrically Controlled Railway Points and Signals.
Filed: 1906-11-27
Granted: 1907-07-11
Abstract: 26,985. Siemens Bros. & Co., and Ferreira, L. M. G. Nov. 27. Interlocking-apparatus for hand-lever interlocking - frames of the kind in which an electro-magnetic locking-device locks the mechanical interlocking - apparatus until the points or signals have arrived at their final position. The electro-magnetic locking-device locks the handlever in the position which causes operation of the motor, and prevents its further movement into the final position in which the motor lead is earthed to allow reverse motion of the motor for the purpose described in Specification No. 10,778, A.D. 1906, until the points have attained their final position, and are locked. The locking-device is positively moved into the locking position upon reversal of the hand - lever, and the operation of the electric switch controlling the points circuits is effected by the interlocking-tappet itself. Fig. 1 shows a back view, and Fig. 2 a side sectional view of the frame, in which each hand-lever a is provided with the usual interlocking tappet b, a notch n being formed in the side of each tappet b to engage with a lug m on an horizontally-sliding bar k .actuated by one arm h of a three-armed lever pivoted at i. The arms f, g of this lever form armatures of electro-magnets d, e, which are energized respectively upon completion of the motion of the point's tongues in either direction. Plates o cover the notch n in such a manner that one plate o covers the upper part of the notch, while the other plate o covers the lower part of the notch on the opposite side of the tappet. A tongue p forming part of each plate o projects obliquely at the end that is next the uncovered portion of the notch n. An electric switch lever q pivoted at s is actuated by engagement in a notch r of the tappet b, so that pins t, t<1> consecutively connect pairs of springs u, u<1> in either extreme position of the tappet b, the springs u being in the circuit of the points motor, and the springs u<1> being in the earth circuit of the motor lead for reversal. In the position shown, the energization of the magnet d was the last operation, and the armature f is retained in the attracted position by engagement of the lug m against the side of the tappet b. A spring pin v engages in a notch w in the tappet b to maintain this position effectively. When the hand-lever a is moved over from this position to operate the points or signal, the tappet b is raised, and the slot n registers with the lug m, so that the three-armed lever may return to its normal position by means of gravity, or by the action of a spring x, or, failing these, by the positive engagement of the tongue p and lug m causing the sliding motion of the bar k. The tappet b is then raised until the lug m engages with the base of the slot n, and the switch q is in the position shown in dotted lines, and connects the springs u for operation of the points motor. When the points are fully over, the magnet e is energized, attracts its armature g, and withdraws the lug m from the notch n, so tbatthe motion of the lever a may be completed, and the switch q thereby moved into contact with the springs u<1> to complete the earth circuit of the motor ready for reversal. The end position is maintained by engagement of the spring pin v in the notch w<1>.