Patent GB-557082-A (GB)
Title: Improvements in or relating to carriage driving mechanism for punching machines
IPC: G06K13/077
Filed: 1942-04-30
Abstract: 557.082. Punching record-cards. BRITISH TABULATING MACHINE, CO., Ltd. April 30, 1942, No. 5857. Convention date, May 2, 1941. [Class 31 (ii)] A punching-machine such as is used for punching record-cards is constructed with a carriage C for the cards, and the movement of the carriage is controlled by escapement mechanism and a relatively movable piston and cylinder the carriage being connected with the movable element operated by an air pump which normally tends to move the carriage in the operative direction, but is reversed automatically at the ends of the carriage movement. The escapement mechanism may be controlled by a tabulating mechanism to skip certain of the punching positions, and a switch may be operated to cause the card to be ejected at the end of a desired number of punchings, and in any case the card is ejected when the carriage reaches a predetermined position. The invention is described in connection with a machine of the kind described in Specification 471,069 in which the actuation of punches 120, Fig. 2, is controlled by keys 100 which also actuate type-bars, or is controlled by a perforated master card. The card is held to the carriage by pivoted card fingers 73, 75, and the carriage is attached to a cylinder 70 which moves to the left under control of an escapement pawl 82, fixed rack 71 and spring-biased dog 81. The air-pressure is produced by a pump 35 and a valve 55 is operated to cause the air pressure to tend to move the carriage to the left, but the valve can be reversed in order to return the carriage. Normally the operation of the printing keys actuates a rod 91 to release the escapement mechanism to cause a unit movement of the carriage C corresponding to the distance between each row of perforations. To perform a tabulating operation consisting in causing the carriage' to skip to a predetermined column a clip 126 is attached to a rack 125 at the required columnar position and a tab key 130, Fig.5, is depressed to energize a solenoid 132 and a plunger is operated to bring an arm 145 into line with the clip 126 and also to release the escapement mechanism so that the carriage can move freely until the clip 126 is engaged. An arm 141 on the shaft of arm 145 operates a bleeder valve to reduce the effective air pressure tending to move the cylinder 20 so as to prevent too rapid movement of the carriage. During this movement of the carriage a contact 155 is operated to maintain the energization of the solenoid 132, and a contact 154 is operated to open the holding circuit when the clip 126 stops the carriage. To release the carriage C from any position so as to skip the last columns a switch 165 is closed to energize a solenoid 160 to energize the solenoid 132. The solenoid 160 actuates an interposer 161, Fig. 3 (not shown) to prevent operation of the tabulating arm 145. A relay winding 163 with three sets of contacts 163a, 163b, 163c is also energized by switch 165 and these act to keep the solenoids energized and also to cause energization of a clutch solenoid when contacts 138 are closed by the cylinder 70 when it reaches its extreme position to the left. The cylinder 70 at the same time opens contacts 137 to de-energize the solenoid 132. The clutch solenoid releases a one-revolution clutch which operates cam mechanism to cause release of the card finger 73 and engagement of the card by a pair of rollers which eject the finished card. The cam mechanism also closes a switch 180 which energizes a solenoid' 57 adapted to reverse the valve 55 of the pump. At the end of the return movement of the carriage the pump valve is restored to normal position, and the carriage is stopped automatically.