Patent GB-358479-A (GB)
Title: Improvements relating to remote control apparatus
IPC: B61L7/08
Filed: 1930-07-01
Abstract: 358,479. Railway signalling systems. WESTINGHOUSE BRAKE & SAXBY SIGNAL CO., Ltd., 82, York Road, King's Cross, London. -(Assignees of Snavely, C. S. ; of Union Switch & Signal Co., Swissvale, Pennsylvania, U.S.A.) July 1, 1930, No. 19956. Convention date, July 17, 1929. [Class 105.] In remote control apparatus for controlling train-governing devices and giving a return indication, signals are transmitted by codes, each consisting of a number of successive elements of two or more different characters, and each element of the code transmitted from the point of control is arranged to be received by all of a number of devices at each remote point to be controlled, each device being responsive only to a code element of a particular character, another device at each remote point being responsive to a particular sequence only of operation of the first devices. Fig. 1 shows equipment at a train-despatcher's office, and Fig. 2 apparatus at a remote point. Each code element is an impulse of periodic current of distinctive frequency, the currents being supplied by alternators X, Y, Z. The connections of the alternators to line wires 1, 3 are controlled by electromagnets AD x, AD Y, AD z, which are energized through means including a stepping contactor P A operated by an electromagnet F<A>. Associated with the contactor is a master relay J A, a starting relay x, and two timing relays i A, j A. Panels BB, CC, &c. are provided, one for each remote station to be controlled. Panel BB has two manually-operated switch devices BE', BE<2>, each comprising a cam lever 12 adapted to operate a follower 13 and to move a contact 14 into engagement with one of a number of fixed contacts. The device BE<1> is for the purpose of operating track points and the device BE<2> for operating railway signals at the remote station. Handles 27, 28 are provided on a track model 26 for the operation of the switch devices. At the remote station corresponding to panel BB, a section of track a-b provided with track points 50 leading to a siding 51, is shown. The section has a track circuit including a battery 52 and a track relay v. The points 50 are operated by a motor g controlled partly by two relays p<1>, p<2>, and, in turn, control a pole-changer 55 governing the polarity of current to an indication relay k. The points 50 also control contacts 56, 67. East-bound traffic through the section a-b is controlled by signals w<1>, w<2>, west-bound traffic by signals w<3>, w<4>, these four signals being controlled partly by signal relays q<1>, q<2>. Transmission of signals from train-despatcher's station. Assuming that the despatcher wishes to reverse the points 50 at station B, he reverses the position of handle 27, Fig. 1, thereby causing member 18 to move to the left to close contacts 20, 21. At full reverse position of handle 27, member 18 returns to the position shown, to close contacts 19, but contacts 20, 21 are kept closed by the latch 23. A circuit is then complete through back contact 42 of relay x, contacts 43, 43a of relay J A, contacts 20, 21 of panel BB, contacts 19, and winding 25 of code-setting relay BW. This relay operates, causing finger 24 to raise latch 23 but to maintain contacts 20, 21 closed, and also closes the group of code-setting contacts 49. A circuit is then closed through back contact 42 of relay x, winding 58 of relay J A, contacts 24, 20 and 20, 21, contacts 19, and winding 25 of relay BW. Winding 58 is thus energized to close contacts 43, 43b, whereby a circuit is complete for the stepping magnet F A of contactor P A. This magnet at contact 48 completes a circuit through contacts 33, 35 of contactor P A, contact 49 of relay BW, and winding of magnet AD Y. The magnet AD Y closes contact 10 to connect alternator Y across lines 1, 3 so that an impulse of current to these lines is delivered to form the first code element. The magnet F A at contact 46 completes a circuit through winding of relay i A which acts to energize relay j<A>, the latter relay at contact 45 opening the circuit of magnet F A. The release of the magnet steps the contactor P A one step to deenergize magnet AD Y and terminate the first element of the code. The other elements of the code are delivered while the contactor PA engages in succession the segments 36 .. 41. The first four code elements are utilized for selecting a particular station and the remaining two elements for causing a particular operation at the selected station. The de-energization of magnet F A after the sixth element of the code has been delivered advances the wheel 33 into engagement with segment 41 so that when magnet F A is again energized a circuit is complete for relay x. This relay at back contact 42 opens a locking circuit for relay BW so that finger 24 is released, allowing contact 20 to return to its original position to close contacts 20, 22. The closing of the front contact of relay x energizes winding 59 of relay J A to open contacts 43, 43b whereby the circuit for stepping magnet F A is opened and the wheel 33 is advanced to re-engage segment 35, and cause relay x to de-energize. Receipt of signals at remote point. At each station a transformer such as t B is provided, the secondary of transformer t B supplying energy to relays BG x, BG Y, BG z, in circuits tuned to currents of the frequencies supplied by alternators X, Y, Z respectively, so that relay BG x, for example, closes its front contact in response to a code element from alternator X. A slow-release relay BH is adapted to be energized when any code element is supplied to lines 1, 3. Decoding relays BN<1>, BN<2>, &c., are provided to control the apparatus at the remote station, these relays being constructed to respond selectively to specific control codes originating at panel BB. For example in response to the control code delivered when handle 27 is moved to reverse position decoding relay BN<3> is operated to close its contacts 68, 70. Current then flows through winding 81 of relay BL3 causing contacts 83, 83b to close, whereby a circuit is completed through contact 56 and winding of relay p<2>. This relay energizes to cause the operation of motor g which moves the points 50 to their reverse position. The movement of the points opens contact 56 to de-energize the motor g. The remaining five decoding relays in a similar manner control other operations at the remote station. Construction of decoding relays. Figs. 3, 5, and 6 illustrate a form of decoding relay for use in the system described with respect to Figs. 1 and 2. This relay comprises a casing containing three stepping magnets 62 x, 62 Y, 62 z, and a holding magnet 62<H>, each stepping magnet being associated with one of three relays G x, G Y, G z. The magnets are arranged on a magnetizable core 63 provided with outstanding legs 71. A rotatable shaft 66 biased towards a stop position has rigidly attached thereto driving discs 64 x, 64 Y, &c., each provided with openings 80 adapted to receive magnetizable slugs 76. Pivotally supported between each pair of legs 71 is an element 73 carrying two fingers 75 of magnetic material disposed on opposite sides of a disc. Each element is biased by a spring against a stop 78. If, for example, stepping magnet 62 x is energized the corresponding element 73 is moved in a clockwise direction and the slug 76 being attracted causes the disc 64 x to move also. The holding magnet 62<H> is provided with magnetizable legs 79 on opposite sides of a disc 64<H> provided with slugs 76 corresponding to every position of the shaft. When a code element to which relay G x is responsive is transmitted relays G x and H are both energized and shaft 66 is moved one step, relay H, which is slow to release, causing the energization of relay 62<H>, whereby the shaft 66 is held in its new position pending the transmission of a new code element. If now relay G<x> is again energized a further movement of shaft 66 does not take place since there is no slug in the second of openings 80 but the opening of the circuit for the magnet 62<H> during the transmission of the code element allows the shaft 66 to return to normal. The arrangement is such that shaft 66 will not make a complete movement of six steps unless the sequence of operation of the relays G x, G <Y>, G z corresponds to the positions of the slugs 76 in the associated discs. This complete movement causes the engagement of contacts 68, 70, whereby the apparatus at the remote station is put into operation. Transmission of supervisory signals from a remote station. Indication codes similar to the control codes already described are employed for transmission of supervisory signals from each remote station to the train-despatcher's station. At the latter station relays AG x, AG Y, AG z are provided which are tuned to resonance at the frequencies of alternators X, Y, Z, respectively. At station B electromagnets BD x, BD Y, BD z are provided which when energized complete circuits tuned to resonance at the frequencies of the currents supplied by alternators X, Y, Z, so that the energization of magnets BD x, BD Y, BD z, causes the energization of relays AG x, AG Y, AG z, respectively. The magnets BD x &c. are energized in definite sequences by means of a stepping contactor P B adapted for the transmission of seven code elements. The delivery of indication codes is initiated by the reversal of master relay J B controlled by polarized indication relays r<1> .. r6. Relays r<1>, r<2> are associated with the position of points 50, r<3>, r<4> with the position of the signals at station Band r<5>, r<6> are controlled in part by the track relay v and are utilized to inform the despatcher when a train leaves section a-b. Assuming that points 50 are moved to reverse position, the initial movement of the points causes relay k to become de-energized whereby a circuit is completed through back contact 113 of relay k, for winding 114 of relay r<1>, and winding 115 of relay r<2>. Relay r<1> i