Patent GB-463977-A (GB)
Title: Improvements relating to telegraph printing, recording and like apparatus
IPC: H04L15/34
Filed: 1935-10-08
Abstract: 463,977. Type-printing telegraphy. CABLE & WIRELESS, Ltd., and WARBURTON, F. Oct. 8, 1935, No. 27825. [Class 40 (iii)] [Also in Group XVI] In printing-telegraph apparatus for receiving code signals of unequal length, the type levers are controlled by a series of levers carried by a continuously oscillating shaft, and on the receipt of a signal a selected member moves into the path of the appropriate lever and thereby modifies its motion to effect the printing operation. The apparatus may operate on the start-stop principle. The selecting mechanism is the same as that described in Specification 463,975, and comprises six pairs of permutation bars, 56, Fig. 5, one member of each pair being shifted by a power-driven actuator 7. At the end of each signal a spacing bar 74 is shifted by the forward movement of the actuator 7 through a link 76 to allow an appropriate one of a series of exploring blades to enter aligned notches in the bars. The other end of the blade then strikes a lug 104a on a three-armed lever 104, Fig. 4, and swings it sufficiently for a hook 104d thereon to engage a latching member 106. Printing operation. A blade spring 108 carried by the selected lever 104 moves a slide 109 to the right (Fig. 4), into the path of a type-actuating lever 111. The levers 111 are carried by a shaft 112 which is oscillated vertically by an eccentric on a shaft driven either at signal element speed or at half that speed. The point at which the levers 111 strike the slides 109 is adjustable either manually or automatically in accordance with the speed of the shaft by a sliding bar 127 which raises or lowers a member 123 having a slot 123a through which the slides pass. The lever 111 on striking the displaced slide 109 swings about its shaft 112 and raises a rod 120 to actuate a type-lever 98. At the same time a dog carried by the shaft 112 strikes the tail of the latching member 106 and releases the lever 104. Strip feed. The raising of the first lever 37 or 38 into engagement with a permutation bar rocks a lever 130 which depresses an arm 132 pivoted on the link 76 to the position shown in Fig. 5, and becomes locked thereto by a latch 134. When the link 76 is moved by the actuator 7 to shift the spacing bar 74, the arm 132 is unlocked and rocks a bell-crank lever 136 to withdraw a stop 138 which normally prevents engagement with the ratchet of the feed roller 149 of the driving pawl 146, the latter being pivoted on a continuously oscillated arm 140. For word spacing, the strip may be fed during every unperforated centre hole period, or the feed may be dependent on a specific signal. A lever 250, Fig. 7, controlled manually or automatically from the transmitter brings into operation alternatively two exploring blades 153, 154, one of which is effective when only the spacing bar is displaced and the other when the specific signal is received. Either of these blades rocks a lever 155, which becomes latched and moves a member 157 into the path of an oscillating dog 160 so that the movement of the latter rocks the bell-crank lever 136 which effects the feed of the strip as described above. At the same time the lever 155 is unlatched. The specific signal results in three feed steps, one by the operation of the spacing bar, one by the action just described and the third before the printing of the next character. The automatic feed may be stopped by operation of a self-locking lever 162, Fig. 5, which tilts the link 76 to prevent movement of the spacing bar by the actuator 7. If signals are received while this condition obtains, the movement of the arm 132 unlatches the lever 152. Calling signals. An exploring blade which is effective in response to a special signal serves to close self-locking contact springs, which start a perforator or other instrument. The springs are returned by the action of another blade which is effective in response to a restoring signal. Irregular operation. A scrutinizer blade 182, Fig. 9, co-operates with wide notches in the permutation bars 56, so that, provided the spacing bar 74 is shifted, it tends to be affective whatever the setting. If however, eny other exploring blade is effective, the three-armed lever 104 acts through a crossbar 188 and levers 186, 190 to swing the blade 182 away from its three-armed lever 183. If more than six impulses are received without a spacing interval, an additional bar is shifted, as described in Specification 463,975, and only the blade 182 is effective. In this case the three-armed lever 183 acts like the levers 104 and brings about the printing of a warning mark. The lever 183 is arranged to be operated somewhat later than the levers 104. A further exploring blade is effective if only the spacing bar is shifted in order to disable the blade 182 when the automatic word spacing blade is in operation. The blade 182, if effective, also allows a lever 195 to shift and latch, bringing contact springs 205 under the control of a vibrating lever 199 to send a warning signal until a ratchet-driven cam 204 unlatches the lever 195. Synchronizing signals. These are alternate positive and negative impulses and are sent during idle periods. To prevent their affecting the selecting mechanism, contact springs 231-233, Fig. 10, are closed intermittently to short-circuit the magnets by depression of the lever 162 which brings a bell-crank lever 225 under the control of one or other of two cams 223, 224 rotated at half the speed of the power shaft. In order. to apply the short-circuit at the appropriate times, the lever 225 may be moved opposite either of the cams 223, 224 by an arm 234. Finger keys may be attached to the threearmed levers 104 for direct manual operation. Specification 463,976 also is referred to.