Patent GB-361412-A (GB)
Title: Improvements relating to electrically controlling railway points and signals and the like
IPC: B61L7/08
Filed: 1930-08-21
Abstract: 361,412. Operating railway signals and points electrically. WESTING- HOUSE BRAKE & SAXBY SIGNAL CO., Ltd., 82, York Road, King's Cross, London. -(Assignees of Pelikan, J. M.; 5031, Bayard Street, Pittsburg, and Brooks, C. A.; 1429, Macon Avenue, Swissvale, both in Pennsylvania, U.S.A.) Aug. 21, 1930, No. 25006. Convention date, Sept. 30,1929. [Classes 104 (i) and 105.] In a system for controlling railway points and signals from a distant point, only two line conductors are used for each control lever, the same conductors serving to transmit indications of the condition of the apparatus controlled. The system is shown applied to a pair of points F and four signals S<1> .. S<4>; the section of track over the points has a track-circuit controlling a relay G. Operation of points. The point operating circuits pass through contacts 28, 29 of a polarized relay T controlled by a two-position lever V<1> in the control office; 'the relay T has two special contacts 10, 21, arranged so that each closes before the other opens. In the position shown, relay T is energized from battery Q<1> over a circuit, called the second normal stick circuit, containing a contact of lever V<1>, the winding of an indication relay N<F>, the contact of relay G, a contact 8 operated by the points, and contacts 9, 10 of relay T and 11 of a relay t. Relay N<F> is energized to light the indication lamp e<1> over a contact of lever V<1>. When lever V<1> is moved, the circuit is broken momentarily, and relays N<F>, T are de-energized. The lever then completes a reverse pick-up circuit for T from battery Q<2>, passing through contact 21 of relay T ; N<F> is a slow pick-up relay and does not respond to this current, but relay T operates, closing contacts 10, 9 reversed to complete a first reverse stick circuit from a local battery Q<4> over point contact 25, contacts 9 reversed, 10, 11 of relavs T, t. Contact 21 is then broken, but a circuit is made from battery Q<2> passing through contact 27 of T and the winding of t; the current in this circuit is, however, insufficient to operate relays N<F>, t. When the points complete their movement, the second reverse stick circuit is completed from battery Q<2> through point contact 25 reversed and relay contacts 9 reversed, 10, 11. Relay N<F> is thus energized, and completes the circuit through a reverse lever contact for indication lamp e2. If the points do not complete their movement, the first reverse stick circuit remains complete, and the lever V<1> can be returned to normal to energize relay t from batteries Q<1>, Q<4> in series over a circuit containing point contact 25 and relay contacts 9 reversed and 27 ; t breaks the circuit for T, which drops, thus de-energizing t to complete a normal pick-up circuit for T from battery Q<1> over relay contacts 11, 21, so that the points are returned to normal. If the points are displaced after completing their movement, the second stick circuit is broken and the first is made, de-energizing the indication relay but holding the point control contacts in a position to return the points to their correct position. When the track circuit is occupied the circuit of the relays T, N<F> is broken at relay G, so that the points cannot be moved and no indication is given. Operation of signals. The signal operating circuits pass through contacts 46, 47 of a relay H, similar to T, and also through selection contacts 30, 31 operated by the points. The relay H is controlled by a three-position lever V<2>, which is moved to the right to operate signals S<1>, S2 and to the left for signals S<3>, S<4>; this relay also has special. contacts 37, 43 similar to contacts 21, 10 of relay T. A relay h, corresponding to t, is provided. To operate signal S<3> or S<4>, according to the position of the points, lever V<2> is moved to the left from its normal mid-position to complete a pick-up circuit for relay H from battery Q<1> over contacts 37 of H and 38 of h. The indication relay N<S> is normally de-energized and picks up slowly, like N<F>, so that no indication is given by this circuit. Relay H moves or holds its polar contacts to the left, and completes a first stick circuit from local battery Q3 over contacts 38 of h, 43 of H, back contact 42 of a relay L and polar contact 41 of H. A circuit is also completed from battery Q<1> through relays H, h, N
 in series over contacts 38, 43, 45 of h, H, but the current is insufficient to energize these relays. When the signal completes its movement, it closes a contact such as 49 to energize relay L and complete the second stick circuit for H from battery Q<1> over relay contacts 38, 43, 42 (front) ; relay N
 is energized in this circuit to lift lamp e<3> over a lever contact. If the signal does not respond to the lever, the first stick circuit remains complete ; the lever may then be returned to the mid-position, completing a circuit for h from relay Q<3> through the lowest contact of lever V<2>, relay N
 (which does not respond), and contacts 45 of H and 42 (back) of L ; the circuit of H is thus opened at contact 38, and h is then de-energized by the opening of contact 45 to restore the initial conditions. If the signal drops from the "off" position, relay L is de-energized, so that the second stick circuit is broken and the first made and the indication relay is de-energized. Signals S<1>, S<2> are similarly controlled by the lever V<2> in the right-hand position, and are indicated by lamp e<4>.