Patent GB-835939-A (GB)
Title: Code-form converter and communication system
IPC: H04L1/00
Filed: 1957-05-15
Abstract: 835,939. Type-printing telegraphy. COMMERCIAL CONTROLS CORPORATION. May 15, 1957 [Sept. 5, 1956], No. 15456/57. Class 40 (3). A telegraph transmitting or receiving arrangement for an equal-unit binary code comprises a number of storage members individual to the elements of the code and associated with cam and follower means arranged to condition the members selectively in accordance with the code elements, the same cam means subsequently operating to translate the selective positioning of the members as an electrical signal having its code elements arranged in a series or simultaneous code-form presentation respectively, for the transmission or reception operation. Transmitting arrangement, Figs. 3, 4, 5 and 6.-The cam-shaft 39 for controlling the storage members is driven by a gear 77 and clutch 42 from a gear 24 driven by an electric motor. A clutch sleeve carrying spring-engaging hub portions of the gears 24, 77, 44 is provided with a lip portion 46 normally engaged by a projection 47 on the armature 48 of a magnet DCM when de-energized. When the magnet DCM is energized, the gear 77 is driven through one revolution until the lip 46 engages projection 47 and a detent 53 engaging a cam 52 arrests the movement of the clutch shaft in the reverse direction and the amount of overtravel of the hub 43 of the driven shaft is limited by a stop member 56 adjustable relatively to a slot 58 in the clutch sleeve 44. A bail 61 having a roller 63 engaged by a cam portion 64 on the member 56 has an inturned portion 65 which restores the armature 48 to the released condition prior to the end of the clutch cycle. The releasing force applied by the spring 71 to the armature can be adjusted by pivoted lever 72 engaged by a set-screw 74. The cam-shaft 39 carrying a start-stop cam 80, code element cams 81 ... 87, an intermediate cam 88 and a stop period sampling cam 90 is driven by an adjustably mounted gear 78 meshing with the gear 77. The pivoted follower arms 92 guided by slots 97 in a scrub member are associated with similar cams 81 ... 87 having angularly-displaced recesses, and the upper ends 98 of the arms 92 are associated with notches 99 in the armatures 100 of the magnets DM. When a magnet DM is energized, its associated follower arm 98 is unlatched and engagement with the recess of its associated cam rocks a bail member 121 and a pivoted frame 122 so that a saddle member 124 closes contacts DCSC for the element period. A pivoted lever 113 engaging the start-stop cam 80 rocks the bail 121 to close the contacts DCSC for a period at the end of a revolution of the cam-shaft 39 and at the beginning of the next revolution, and the cams 80, 81 are relatively arranged so that for a period corresponding to the element the contacts DCSC are open to provide the start element. During the period preceding the start element, slightly raised projections on the cams 81 ... 87 move all the followers 92 to the left whilst the armatures of the magnets DM are relatively actuated, and subsequently the unlatched arms 92 move to the right under their associated actuated armatures 100, and later engage the recessed portions of their associated cams. An arm 116 connected to the lever 113 holds contacts DSSC open during the period of the stop element. Near the end of a revolution of the cam-shaft 39, a projection 107 on the cam 81 moves its follower arm 92 to the left to rock a pivoted bail member 108 carrying a bar 110 which is moved downwardly so that all the armatures 100 are in their unactuated (released) positions. The intermediate cam 88, which is rotatively adjustable on the shaft 39, operates via roller 129 and link 130 contacts DIC of which the operational period is adjustable relative to the first code element controlled by cam 81. The sampling cam 90 operates via arm 139 and link 140 to close the contacts DSPC for a short interval during the stop period. The contacts and operating elements are mounted on a quadrant 135 rotationally adjustable about the shaft 39 so that the sampling interval can be selected in relation to the home position of the cam-shaft 39. Receiving arrangement, Figs. 10 and 14.- The start pulse is effective to energize magnet CCM attracting its armature 48<1> to allow clutchshaft 38<1> to be driven through one revolution. The detent arm 53<1> is provided with an extension 163 operating contacts CDC, and an arm 621 connected to the armature knock-off bail 611 has a pivoted extension 168 operating contacts CKOC in series with the operating circuit of the magnet CCM. A gear 77<1> on the shaft 38<1> meshes with a gear 170 on a receiver arm shaft 159 carrying seven similar, but angularly displaced, cams 171 having operating projections 172 and reset rollers 173. The projections 172 co-operate with operating extension 180 on pivoted follower arms 176 carrying latching members 178 normally held against stop-rods 185, 186, springs 184 connected to associated contact-operating levers 182 normally latched in their lower positions by ledges 188 engaging under extensions 189 provided on the members 178. The armature 197 of the receiving selector magnet CSM has a widened end portion extending adjacent verticallydisposed tabs 196 on the members 178. When the magnet CSM is not energized by a received code element, the lever 178 engaged by its projector 172 rocks about the lower rod 185, but the energization of the magnet CSM by a mark element moves the armature extension to obstruct the movement of the upper end of the member 178 when its projection 180 is engaged by the associated cam projection 172. The member 178 now rocks about the upper rod 186 and the projection 189 is moved from latching engagement with the ledge 188 on the lever 182 which moves upwardly, and through a connecting link 191 closes associated contacts CC. When the seven pairs of contacts CC have been selectively closed, a circuit is completed by contacts CTPC, operated by a transfer cam 212, simultaneously through a group of punching magnets to perforate the received code combination. The rollers 173 restore the levers 182 to their latched positions a short time before their associated members 178 are actuated by the operating projections 172. The armature 197 is latched in its selected position immediately prior to the operation of the members 178 by a lever 176 carrying an inclined locking bail 195 engaging above or below the knife-edge of a tab 202 on the armature 197. The start magnet CCM together with its operating elements and the contact assemblies CDC, CKOC are mounted on a quadrant 161 rotationally adjustable relatively to the shaft 38<1>. Circuit arrangements.-In the half-duplex arrangement shown in Fig. 22 the line circuit between terminals T1, R8 includes the transmitting contacts DCSC closed during the stop element period, the winding of receiving relay RLR, closed contacts 17, 18 of normally energized error relay PER and tape-feed contacts TFS, connected to similar elements at the distant station. If the left-hand station is to transmit, switch S1 is moved to contact 2, transmit relay TR energizes, and relays RLR, RLR<1> will be operated. The transmitter distributer will operate and the start element releases relay RLR<1> which through contacts 1, 2 and 11, 12 of unoperated relay TR<1> and closed contacts CKOC<1> energizes the control magnet CCM<1> of the receiver. The transmitted marks and spaces pass to the selector magnet CSM<1>. If, during the stop element period, the line circuit is opened, relays RLR, RLR<1> become de-energized and at the transmitting station, a circuit is completed for reader dot relay RSR which inhibits further transmission and effects release of error relay PER. At the receiver, the magnet CCM<1> is energized by the release of relay RLR<1>, and the distribution performs a cycle and responds to an all-spacing signal, the error relay PER<1> becomes do-energized and permanently opens the transmission circuit. Release of relay RLR during transmission of the code element does not operate relay RSR since contacts DSPC are open except during the stop element period. When the fault has been rectified the relay PER<1> must be reset manually before transmission can recommence. Full duplex operation is described in connection with Fig. 24 (not shown), which is generally similar to Fig. 22, except that transmitting relays are included in the transmission line at each transmitter, and are utilized mainly to control the operation of the respective reader stop relays, such as RSR, RSR<1> of Fig. 22. Detailed circuit arrangements.-The detailed operation of interconnected stations each provided with a tape reader transmitter-receiver and tape-punch units is described in connection with Figs. 25a to 25e (not shown). Specifications 831,111 and 832,908 are referred to.