Patent GB-780604-A (GB)
Title: Program devices for record card controlled accounting machines
Filed: 1954-12-20
Abstract: 780,604. Statistical apparatus. INTERNA. TIONAL BUSINESS MACHINES CORPORATION. Dec. 20, 1954 [Dec. 23, 1953], No. 36724/54. Class 106 (1). In a programme device for a cyclically-operated recordcard controlled accounting machine of the kind printing on a series of summary sheets the results of calculations performed on data read from record cards, there are provided an electromechanical counter adapted to be stepped from a zero position through a predetermined number of other positions in sequence in successive cycles so as to initiate successive operations of the machine and resetting means operable to reset the cycle counter to the zero position when the, counter reaches a selected one of the positions. In the form described, a ten-step programme switch, Fig. 1, is adapted for use with fewer programme steps (e.g. three steps) by connecting the fourth terminal to a circuit which controls the counter stepping the switch arm A along the terminals 1-10. Normally, the counter advances one step each machine cycle, but this would make it necessary to have seven idle cycles when a three step programme was used. The control circuit of Fig. 2 avoids this. The fourth terminal of the programme switch is connected by a jack to the plug 5, Fig. 2, so that when the switch arm A reaches this terminal a relay 2 is picked up through coil 2E and holds through contacts 2-1 and coil 2M., The counter is driven from a continuously rotating shaft by a clutch controlled by electromagnets 10, 14, Fig. 3, magnet 10 being for starting the movement of the counter and magnet 14 for stopping the counter. The amount of rotation given to the counter is determined by the instant in the machine cycle at which the start magnet is energized. Cam contacts 11 and 13 are provided, either of which may cause energization of the start magnet 10 according to the position of contacts 2-3 of relay 2. Cam contact 11 closes at such a time in the machine cycle that a count of one is added and cam contact 13 adds a count of nine. The operation is therefore as follows : when the switch arm 1 reaches the fourth terminal, relay 2 is picked up and contacts 2-3 transfer so that the counter comes under the control of cam contact 13. The addition of nine causes the arm A to run quickly up terminals 4-10 at which point a connection is made to stop magnet 14 as shown in Fig. 3, which stops the counter with the switch arm A on the first programme terminal. The programme switch therefore advances one step for each machine cycle through positions 1, 2, 3 and in the fourth cycle it passes from position 4, through position 10 to the starting position ready for the next printing operation. Machine control-The record cards controlling the machine are arranged in groups, the cards being fed through the sensing means until a change of group is detected. The number in each group is counted by a card counter during the sensing operation and the data is processed in a calculating device. When a group change is detected, the card feed stops and the feed of summary sheets to the printing apparatus is started. The programme switch sends a value of minus one to the card counter each time it passes through the second cycle so that the value in the card counter is reduced each time a summary sheet is printed. When the card counter is returned to zero, indicating that the same number of summary sheets have been made as there were detail cards in the group, the printing process stops and the feeding of the next group of cards begins. The process repeats automatically. The exact printing programme to be carried out is determined by circuits connected to the switch terminals by plug connectors.