Patent GB-121914-A (GB)
Title: Improvements in or relating to Telegraph Systems.
IPC: H04L5/22
Filed: 1918-06-19
Abstract: 121,914. Automatic Telephone Manufacturing Co., Harrison, H. H., and Smith, S. R. June 19, 1918. Type-printing telegraphs; duplex and multiplex telegraphs.-In a type-printing telegraph system of the kind in which distributors are driven intermittingly at approximately equal speeds, one or more transmitting distributors and receiving distributors are arranged at each end of the line and are adapted to be intermittingly operated in succession. The system is arranged for duplex and multiplex working, and starting means are provided at each end of the line to start the distributors at both ends. Means are provided for locking the keyboards of the transmitters during the sending of the impulses of a character. In the arrangement shown in Fig. 1, each end of the line is provided with a receiving distributor D1 and a transmitting distributor D2. The arm CBA1 of the receiving distributor D1 is driven through a friction clutch by a constantly-rotating shaft and is normally held against rotation by a latch L1 controlled by a starting magnet SM1; while the arm CBA2 of the transmitting distributor is similarly driven and held by a latch L2 controlled by a starting magnet SM2. The circuits of the magnets SM1, SM2 are controlled during the operation of the system by relays SR1, SR2; while a starting key 8K directly controlling the magnet SM2 and relay SR1 is provided to start the apparatus. The current impulses of a character are selected by a pole-changer PC operated by a key KL and the unoperated keys are locked against operation during the sending of a set of character impulses by a latch LF controlled by a magnet LM. Operation. To start the apparatus at both stations, a key SK is momentarily depressed to energize the relay SR1 and the starting magnet SM2. The relay SB1 locks up over the armature A6 of the relay SR2 and the armature A3 of the relay SR1 and connects the ring R2 of the distributor D2 to the line L through its armature A2. The energization of the magnet SM2 releases the arm CBA2 which, during its initial movement, sends a starting impulse from the battery LB8 over the ring R2 and line L to the receiver at the distant station. This starting impulse energizes the relay MLR at the distant station to connect the ring R1 of the receiving distributor to a battery LB, thereby energizing the release magnet SM1 to release the arm CBA1. The arm CBA1 rotates and when it engages the contact S6 it causes the energization of the relay SRI of its associated transmitter and the relay LR. The energization of the relay SR1 causes its armature A4 to connect the battery LB4 to the starting magnet SM2 of its associated transmitting distributor which in turn operates to start the receiving distributor at the home station. To send a character, a key KL is depressed to set its pole-changer PC and as the arm CBA2 moves over the contacts TS1, TS2, - - TS5, positive and negative impulses are sent through the relay MLR at the distant station, which impulses selectively energize the setting magnet M1, M2 - - M5 as the arm CBA1 moves over the contacts S1 - - S5. When the arm CBA1 engages the contact S6 it energizes the relays SR1 and LR. The relay SR1 operates to close the circuit of the printing magnet PM through its armature A1 and a condenser C, to disconnect the receiving distributor from the line L and to connect the line L to the ring R2 of the transmitting distributor through its armature A2, to lock itself up over its armature A3 and to energize the starting magnet SM2 over its armature A4. The relay LR operates to energize the key-board locking magnet LM over its armature A5 and to lock itself up over its lower armature and the armature A10 of the magnet ULR. The energization of the magnet SM2 releases the arm CBA2 of the distributor D2, and when the arm engages the contact TS6 it energizes the relay SR2 which operates to break the locking circuit of the relay SR1 at the armature A6 and to energize the magnet ULR over the armature A7 to break the locking circuit of the relay LR. The distributor D2 is thereby disconnected from the line L, the distributor D1 connected to the line L, and the key-board locking magnet LM is de-energized. In the modification shown in Fig. 2. duplex working is obtained by providing each end of the line with two receiving distributors RD1, RD2, two transmitting distributors TD1, TD2 and a differential relay MLR. Operation. To start the apparatus at both stations a key SK is depressed to energize the starting magnet SM3 of the distributor TD1 from a battery LB5. The rotary arm CBA3 in its movement sends a starting impulse to its associated receiver at the other end of the line, and when it engages its contact segments X, it closes the circuits of the relays SR3, LR2. The operation of the relay SR3 closes a locking circuit for itself, disconnects the distributor TD1 from the line L, and connects the distributor TD2 to line. The relay SR3 also closes the circuit of the starting magnet SM4 of the distributor TD2 and allows its arm CBA4 to rotate to send a starting impulse to its associated receiver at the other end of the line. When the arm CBA4 engages the contact segments Y it closes the circuit of the relay SR4 to break the locking circuit of the relay SR3 and close the circuit of the starting magnet SM3 of the distributor TD1, thereby connecting the distributor TD1 to line and releasing its arm CBA3. A starting impulse sent by a transmitting distributor at one end of the line causes the relay MLR at the other end of the line to send a starting impulse on the armature A1 of the relay SR1 to the starting magnet SM1 of a receiving distributor RD1 to release its arm CBA1. When the arm CBA1 engages its contact segment S6 it causes the energization of the relay SR1 by a battery LB3. The operation of the relay SR1 causes its armature A1 to disconnect the distributor RD1 from the line and to connect the distributor RD2 to line; while the relay locks up over its lower armature A2 and the armature A3 of the relay SR2. A starting impulse sent by the transmitting distributor associated with the receiving distributor RD2 causes the relay MLR to send an impulse to the starting magnet of the distributor RD2, and when the arm CBA2 engages its contact S6 it energizes the relay SR2 to break the locking circuit of the relay SRI, thereby disconnecting the distributor RD2 from the line and connecting the distributor RD1 to line. After the above series of operations, the two transmitting distributors at one end of the line and the two receiving distributors at the other end of the line are rendered operative. To send a character by the distributor TD1, a key KL1 is depressed to set the pole. charger, not shown, and the keyboard locking magnet LM1 is energized when the contact segments Y of the transmitter TD2 are bridged to energize the relay LR1 to close the circuit of the magnet LM1, and the locking circuit of the relay LR1 is controlled by the relay SR3. The arm CBA3 of the distributor TD1 similarly controls the circuit of the locking magnet LM2. In a further modification, a station at one end of the line is provided with two transmitting distributors and a receiving distributor, while the station at the other end of the line is provided with two receiving distributors and one receiving distributor. The transmitting distributors at one station are successively connected direct to line and finally the line is connected to the receiving relay which operates to start the receiving distributor. The receiving distributor arm near the end of its travel operates to control the starting magnet of the first transmitter. The first receiving distributor at the other end of the line is started by the reception of a starting impulse and at the end of the travel of its rotary arm places the starting magnet of the second receiving distributor under the control of the line relay. At the end of the travel of the rotary arm of the second distributor the circuit of the starting magnet of the transmitting distributor is closed. In the modification shown in Fig. 4, the control relays are dispensed with and the switching over performed by additional contact rings and brushes on the distributors. When the starting key SK is depressed, the magnet SM2 is energized to release the contact arm CBA3, CBA4 and CBA5 of the transmitting distributor TD. While the contact arm CBA3 is passing over the operative contact segments of the ring TR, the arm CBA4 engages the contact rings RR2 to connect the ring TR to line L, and the arm CBA5 engages the contact rings RR3 to energize the locking magnet LM. After the contact arms have made a complete revolution, the arm CBA4 bridges the contacts W to connect the upper of the rings RR1 of the receiving distributor to line L. The lower ring of the rings RR1 is connected to the line relay MLR and the rings RR1 are bridged by an arm CBA2. Upon the receipt of a starting impulse from a distant transmitter, the starting magnet SM1 is energized to release the arms CBA1 and CBA2. When the arm CBA1 is near the end of its travel, it engages contacts Y to energize the starting magnets SM2 from a battery SB through the arm CBA5 and contacts Z. A construction of rotary distributor is shown in Fig. 5 in which one element SD of a friction coupling, is secured to a continuously rotating shaft S while the other element FD is carried by the part B of a divided sleeve B, C. The part C of the sleeve carries a brush disk BCD carrying a stop pin P adapted to engage an eleetro-magnetically controlled. detent X. The parts B, C are connected by a key and slot and are forced apart by a helical spring.