Patent GB-397247-A (GB)
Title: Improvements in centralised traffic controlling installations for railways
IPC: B61L7/08
Filed: 1932-04-19
Abstract: 397,247. Railway signalling-apparatus. GENERAL RAILWAY SIGNAL CO., Rochester, New York, U.S.A.-(Assignees of Johanek, G. J. ; 54, Gardiner Avenue, Rochester, New York, U.S.A.) April 19, 1932, No. 11222. Convention date, April 30, 1931. [Class 105.] In a centralized control installation for the control of railway signalling-apparatus including a pair of points and the associated signals, the points and the signals are alternately associated, over a common line circuit, with relay devices at the control office to indicate the condition of the points and the signals respectively. The signals are controlled over one line circuit and the points over another, and means are provided to connect the signals with the signal indicating relay when the signal-operating line circuit is energized and to connect the points with the point-indicating relay when the signal-operating line circuit is de-energized. The invention is shown applied to the junction of a passing siding with a single main line, comprising points operated by a point machine SM, Fig. 1B, three-aspect signals 1, 2 for the main line and two-aspect signals 1A, 2A for the siding. A track circuit controlling a relay T is provided at the points. The point machine SM is controlled by a polar relay WZ of the magnetic stick type, with any approach-locking or detector-locking arrangements (not shown) that may be desired. A point repeating relay WP of the polar-neutral type, in which the polar contacts remain closed until the relay is oppositely energized, is controlled by the point detector (not shown), and is energized only when the points are locked in one or the other extreme position. The signals are controlled by relays 1G, 2G, 1AG, 2AG respectively, selected by a polar-neutral relay SZ in conjunction with the point repeating relay WP, suitable route-locking, time-locking and other arrangements (not shown) being provided. Polar-neutral relays 1H, 2H are provided, controlled, in the usual manner employed in absolute permissive block systems, by the traffic conditions on the main line ahead of signals 1 and 2 respectively, these relays being de-energized when the section immediately ahead of the corresponding signal is occupied, and being energized, when this section is clear, with a different polarity according to whether the second section ahead of the signal is occupied or clear ; the polar contacts of relays 1H, 2H determine the " off " indication (yellow or green) of the signals 1, 2 respectively. Indication relays 1M, 2M are provided, energized when 1G, 1AG and 2G, 2AG respectively are de-energized. At the control office are a point control lever SML connected with the relay WZ at the station over line wire 9, the circuit including a repeating relay WZR, and a signal control lever SGL connected with the relay SZ at the station over line wire 10, this circuit also including a repeating relay SZR. There are also miniature points ts, controlled by a polar-neutral point-indicating relay WIR, signal indicating lamps WI, EI for signals 2, 2A and 1, 1A respectively, controlled by a polar-neutral signal-indicating relay SIR, a track-circuit indication lamp I controlled by a slow-release relay OS, and a correspondence indication lamp CI to indicate whether the points, the point control relay WZ, and the point lever SML are in corresponding positions, this lamp being controlled by a stick relay COR. The relays WIR, SIR are preferably slow-acting so that no wrong indication can be given if their controlling relays SZ, SZR should operate slightly out of synchronism. Under normal conditions, the apparatus is as shown, the relays WZ, WZR being energized from the office battery, over line wire 9 from lever SML normal to hold the points normal, and relay WP being energized ; a circuit is thus completed from the station battery over contact 33 of relay WZ, contacts 35, 37 of WP, and back contacts 39, 40 of relays SZ, SZR to energize WIR as shown. The miniature points ts are thus held normal by a circuit including the second polar contact of WIR, and a circuit is made through the neutral contact of WIR, the lower contact of lever SML and the first polar contact of WIR to energize relay COR, which extinguishes the lamp CI to indicate that the points (repeated by WP), relay WZ and lever SML are in correspondence. Relay OS is energized by WZR, which is controlled over the front contact of the track relay T, and lamp I is therefore out to indicate track clear." Lamps WI, EI are out to show signals on." Operation. To move the points, lever SML is moved, reversing relay WZ and breaking the circuit of COR ; relay WZ breaks the circuit of WIR, and causes reversal of the points, WP being de-energized during the movement and becoming reversely energized on completion of the movement, when WIR is reversely energized to reverse ts and complete a circuit for COR again. To move signal 1 or 1A, lever SGL is moved to the right, closing its left-hand contact to energize relay SZ to the left and also to energize SZR ; this circuit includes the line wire 10 and front contacts of relays COR, T and WP. Relay 1G or 1AG is thus energized, according to the position of the points, through the lowest neutral and polar contacts of WP and the first or second neutral and polar contacts of SZ, operating the appropriate signal relay 1G cannot be energized unless 1H is also energized. Energization of relay SZR completes a stick circuit for COR, and opens the circuit of WZ and WZR to prevent movement of the points ; WIR is also de-energized. Track relay OS remains energized through the back contact of WZR and second front contact of SZR. Energization of relay 1G or 1AG causes de-energization of relay 1M, which connects the station battery with the indication line wire 11 over front contact 39 of SZ to energize SIR to the right over front contact 40 of SZR, thus lighting the lamp EI to show that a signal has been cleared for traffic from left to right. The signal can be returned to " danger " at any time by returning the lever SGL to mid-position, de-energizing SZ and SZR. When the track circuit is occupied, relay T opens the circuit of SZ and SZR, returning the signal to " danger " and de-energizing SIR to extinguish the signal indication lamp ; WIR is re-energized, but WZ and WZR remain deenergized ; the stick circuit of COR is broken, but the ordinary circuit is restored. Relay OS is now de-energized, and after a time lag to allow SZR and WZR to assume stabilized conditions, the lamp I is lit to show occupancy of the track-circuit. If SGL is left in an extreme position, SZ and SZR will be energized again as soon as the track-circuit is clear, and the signal will work automatically for following movements. If SML. is moved after a signal has been cleared, the points are unaffected until the track-circuit has been occupied, to de-energize SZR, and then cleared, to complete the circuit of WZ and cause reversal of the points. The de-energization of COR consequent upon movement of SML prevents energization of SZ to clear a signal, if lever SGL remains operated, until the points have completed their movement, and the other signal for the same direction is then operated. Manual operation or accidental unlocking of the points causes de-energization of WP, which opens the circuits of SZ, SZR to place or keep the signals at " danger," and of WIR, to de-energize COR, lighting the lamp CI and further opening the signal circuit. Specification 338,826, [Class 105, Railway signals &c.], is referred to.