Patent GB-190413015-A (GB)
Title: Improvements relating to Electric Telegraphy.
Inventor: BROWN SIDNEY GEORGE
Filed: 1904-06-08
Granted: 1905-06-08
Abstract: 13,015. Brown, S. G. June 8. Telegraphs. - Relates to relay or translating devices of the character described in Specification No. 17,786, A.D. 1899, and includes as an essential feature the provision of means for correcting incorrect spacing of the signals received. In the arrangement shown in Fig. 1, the cable relay causes the operation of one or other of the two Post Office relays d, d' according to the direction of the current received. An electromagnet e, shunted at e' to render it sluggish, controls the clutch of the shaft b, and is energized when either relay is operated. Owing to its sluggish action, the armature e<4> remains attracted during the short intervals between successive signal currents, and the shaft b rotates continuously, except when prolonged spaces occur, as between words or messages. At about the mid-point of every signal throughout the word, the cam a<1> causes a contact to be closed at h, the circuit of the battery f being thereby completed through one or other of the coils of a neutral relay i and one or other of the windings of a differentially-wound electromagnet k, according as the relay d or d' is in operation at the moment. Every time the electromagnet k is energized, the clutch of the shaft l is engaged, and the cam m effects the transmission of a signal to the line L from the split battery f<1>, its sign depending on the position of the tongue i<1>. The spacing of these signals throughout a word is uniform, as it depends only on the uniform rotation of the shaft b. If the cam a should rotate while the tongues of both the relays d, d<1> are on their back stops, i.e. while no signal current is being received, both the windings of the differential electromagnet k will receive current, and no signal will be retransmitted. The shaft l may be run a little faster than the shaft b. If the interpolator is to work from cable to land line on the " hybrid" system of signalling described in Specification No. 9231, A.D. 1903, the right-hand clutch is provided with two cams, one giving a " dash" with a short space and the other a "dot" with a long space, one or other of them serving to close a local circuit through a transmitting-relay according to the momentary position of the tongue i<1>. For curb working, a reversing-lever such as is described in Specification No. 17,786, A.D. 1899, may be joined to the right-hand or sending-on cam or cams in such a manner as to change over the line and earth levers or battery at predetermined periods. In the arrangement shown in Fig. 4, a device similar to an automatic transmitter is employed. A differentially-wound electromagnet r controls a clutch r<3> so that, when one of the Post Office relay tongues d<2> or d<3> leaves its back stop d<6> or d<7>, the electromagnet is energized and the disc r<0> set in motion so as to reciprocate the lever r<4>. One of the electromagnets s, s<1> will have been energized owing to the movement of the relay tongue d<2> or d<3>, and consequently one or other of the needles t, t<1> will be caused to actuate the lever u or u<1> so as to transmit a + or - current to line. The device may be arranged for use with hand key instruments or in conjunction with punching-apparatus. Reference is made to Specification No. 3438, A.D. 1903.