The IBM 405 alphabetic bookkeeping and accounting machine (later known as the 405 electric punched card accounting machine) was a combined adding, subtracting and printing machine that printed complete reports from punched accounting machine cards. It could be used to list both alphabetical and numerical details from individual accounting machine cards or to print classifications and to accumulate and print totals, net totals and accumulated net totals. The machine was equipped with an automatic plugboard, similar in principle to a telephone switchboard, by means of which any desired arrangement of data could be obtained from the punched cards. It could list cards at the rate of 80 cards a minute and were accumulated without listing at either 80 or 150 cards per minute as specified. Introduced in 1934, the Type 405 was marketed by IBM until May 1949.
This unusual 1951 view of a 405, not only reveals its some of its internal components, but also marks the reconditioning and reassembly of the 100th IBM 405 by IBM’s manufacturing facility in Rio de Janeiro, Brazil. Pictured here are the assemblers who performed the work. (VV4006)