Patent GB-535740-A (GB)
Title: Improvements in or relating to record-card controlled printing machines
Filed: 1939-10-18
Abstract: 535,740. Typewriters &c. BRITISH TABULATING MACHINE CO., Ltd. Oct. 18, 1939. No. 28189. Convention date, Oct. 18, 1938. [Class 100 (iv)] [Also in Group XIX] Automatic means for checking whether or not the type-members of a record-card controlled printing machine have been set in accordance with the index-points comprises two indicating- means operating in timed relation to the reading of the index-points and arrest of a typemember respectively, and a checking means adjustable to a correct or error setting according as to whether or not both indicating means are operative at the same time. The machine shown in Fig. 1 comprises, as described in Specification 374,960, [Group XIX], type-bars provided with types 73 for printing 12, 11, 10 ... 0, and provided also with a dummy type 73a, the 10-type being selected by the 0-holes. The typebars are advanced by pawls 46 on a cross-head 47 and are arrested by pawls 59 controlled by magnets 58. Each magnet 58 has two switches 98, 102, Fig. 15, the switches 102 being connected to cam-contacts CC-6 which are opened during reading of the 12, 11, 0 holes so that the brush 31 can be caused to read all the holes or only the holes 1 ... 9 by opening and closing the associated switches 102, 98 or vice versa. The type-bars are associated with zero-control devices comprising settable members 110 provided with inter-engaging levers 114 which arrest the type-bars in position for printing 0 or a blank. For determining whether the type-bars have been set in accordance with the holes, the following additional circuits and contacts are now provided:-The type-bars are associated with contacts 168a co-operating with bell-cranks 165 supporting vertically movable bars 164 abutting on levers 158 which are pivoted on the crosshead 47 and engage fingers 160 on the pawls 46. When any type-bar is arrested by its pawl 59, the cross-head causes the pawl 46 to depress the lever 158 and bar 164, and the associated contacts 168a are closed momentarily, the finger 160 then entering a recess 161 to permit return of the lever and bar. When the cross-head returns, a stationary cam 186 releases the levers from the fingers 160. For determining whether the first-column type-bar is set in accordance with the odd holes 1, 3 ... 9, the first-column magnet 58 is connected to commutator C-130, Fig. 15, which closes a relay 131 when the odd holes are read. The relay closes contacts 131a in series with a holding-magnet 133 and a circuitbreaker contacts CB-137 timed to close for one and a half cycle-points when odd-holes are read. The magnet 133 closes contacts 133b, 133c, 133d. The first-column contact 168a is in circuit with a relay R-3, the contact 133b, and circuit-breaker contacts CB-139 which are closed during the latter part of the times at which the contacts CB-137 are closed. If the type-bar is properly positioned, closing of the contacts 133b coincides with closing of the contacts 168a, the relay R-3 is energized, contacts R3a, R3b are closed, and a relay-holding circuit is completed through cam-contacts CC-3. Simultaneously, a circuit is completed through contacts 133c and a relay R-5, contacts R-5a, R-5b are closed, and a holding-circuit for the relay R-5 is established. Under these conditions, a checking-circuit is completed through a wire 141, plug-connection 143, contacts R-5b, R-3b, and a relay 135 which closes contacts 135a in parallel with the camcontacts CC-5 in the circuit of the motor M. The contacts CC-5 open after the fifteenth cyclepoint, but owing to closing of the contacts CC-3 as a consequence of the correct setting of the type-bar, the motor circuit is maintained, printing occurs, and a further cycle follows. If the type-bar is set incorrectly, the circuit of the relay 135 is not completed when the camcontacts CC-5 open, so that the machine is stopped before the printing-hammers 72 strike and the operator is thereby warned that an incorrect setting has occurred. The operator then inserts a rod 183 to block the hammers, and rotates the driving-shaft manually to complete the cycle. For determining whether the type-bar is set in accordance with the even holes 0, 2 ... 8, a circuit-arrangement similar to that described above is provided. The circuitarrangement includes a commutator C-140 and circuit-breaker CB-142, CB-144 which close at even-hole positions, and a relay 132 having contacts 132a for energizing a holding-magnet 134. For determining whether the type-bar is set to print zero or a blank, the circuits include a relay R-7, contacts 133d, 134d which close when the 0 ... 9 holes are read, and camcontacts CC-1 which close when the 1 ... 9 holes are read. If none of the holes 1 ... 9 occurs, the relay R-7 is not energized, contacts R-7b in circuit with the contacts CC-4, 168a remain closed, and a checking-circuit is completed through the contacts CC-4, R-7b, 168a, relay R', and contacts R-3b. If the 0-hole is read, the relay 134 closes the contacts 134c, and the relay R-5 is energized. When the type-bar is properly positioned to print zero or a blank, the checking-circuit energizes the magnet 135, and the motor-circuit is maintained through a contacts 135a when the contacts CC-5 open. The circuits and contacts can be duplicated to provide for the checking of more than one type-bar.