Patent GB-426405-A (GB)
Title: Improvements in or relating to punching machines for perforating statistical record-cards
Filed: 1933-10-03
Abstract: 426,405. Selective punching-machines. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London. Oct. 3, 1933, No. 27208. Convention date, Oct. 4, 1932. [Class 31 (ii)] A punching - machine for perforating statistical record cards and of the kind in which a blank card is fed step by step to bring each column to register with a row of punches by means of automatic escapement mechanism, is provided with electrical plug-in means, and a commutator whereby fields may be skipped automatically without changing the skip bar. The invention as applied to the machine described in Specification 362,529, comprises punch-selecting magnets 10, escapement release magnet 40, magnet 50 to bring brushes 48 into engagement with the master card 45, brushes 54, 55 moved by the rack 35 over contacts 57, and plug sockets and connections 59-63. To reproduce data in selected columns, plugs 60 are connected to the corresponding sockets 59, 61; for columns in which automatic spacing is desired, plugs 62 connect the corresponding sockets 59, 63. To leave a number of columns blank at the right-hand end of a card 19, the next corresponding socket 59 is joined by a connection 65 to a socket 64. On closing the main switch 66, a circuit is completed through line 67, magnet 50, brush 69, roller 47, brush 70, sockets 63, 59, brushes 55, 54, strip 56, contact 36, wire 71, and line 68. Magnet 50 thereby elevates brushes 48 into contact with the master card 45, and the usual circuits for the punch selecting magnets 10 are completed through magnet 50, brush 69, roller 47, the perforations in the master card, brushes 48, cable 72, punch magnets 10, and lines 73, 67. The interposer bar 15 at the same time trips the arm 29 and bail 21, thus freeing the pawl 32 from the rack 35 and closing the contacts 36, 23. The circuit for automatic spacing is from line 67, punch magnet 24, line 74, one socket 61 to one socket 59 and segment 57, brushes 55, 54, strip 56, contact 36, and lines 71, 68. The punch magnet is energized independently of the contacts 23, and depresses the punching bar 16 without operating any punches 17, but actuates the bail 27 to cause spacing of the record cards. Pawl 32 actuated by a second magnet 40, opens the contacts 36 to break the punch magnet circuit, which will be completed again if the next column has a plug connection 60. Manual punching may be effected in those columns without plug connections. When the brushes 54, 55 arrive at a column with plug 65, a circuit is completed from line 67, wire 76, release magnet 40, socket 64, plug 65, socket 59, brushes 55, 54, strip 56, and lines 71, 68. In a modification shown in Fig. 6, the segments 57 may be connected by switches 77 to a line 80 corresponding to the line 74 for those columns to be automatically skipped; or to a line 79 corresponding to the common connection to the sockets 63 for those columns to be punched under control of the master card; or to plugs 78 which may be connected to plug 64 for those columns to be punched manually.