IBM 6640
| Company type | Product |
|---|---|
| Industry | Printer manufacturing |
| Founded | 1976 |
| Headquarters | Austin , United States |
| Products | Inkjet printer |
The IBM 6640 printer, introduced in 1976, was one of the pioneering office ink jet printers and formed part of the Office System/6 word processing lineup. Originally designated as the 46/40, it was subsequently renamed to 6640. IBM highlighted its combination of superior print quality with streamlined automatic handling of cut-sheet paper and envelopes. It offered automatic switching between 10-pitch, 12-pitch, or proportional spacing and supported up to five built-in fonts.
Development and manufacturing
The Office System 6, developed under Fred May by IBM's Office Products Division in Austin, Texas, concentrated on office media systems extending beyond traditional typewriters and copiers. Production was carried out at IBM’s Lexington facility.
Operation
Documents were generated using either Magnetic Card Selectric typewriters or the Office System/6 console. Magnetic card stacks were fed through a reader mounted on the printer’s left side, with communication protocols including BSC and SDLC. The 6/440 and 6/450 models incorporated a 6640 printer without the card reader, connecting directly to their consoles.
The printer was equipped with a large envelope drawer capable of holding 500 envelopes and two paper drawers each accommodating up to 600 sheets, supporting paper sizes as large as 17 by 17 inches. Optional font cards could be added on the right side for additional flexibility. Ink was dispensed in black from a single nozzle as droplets deflected electromagnetically to form characters; unused droplets were recirculated through a gutter system. This continuous stream inkjet mechanism was based on a 1963 Stanford patent licensed by IBM. A related device, the Model 9600 Videojet from A.B. Dick’s Videograph Operations, had been released in 1969 for industrial labeling applications.
Operating at a droplet rate of 117,000 per second, the IBM 6640 printed at a speed of up to 92 characters per second (CPS). Although slower than some competitors that reached speeds up to 1375 CPS, it delivered higher print resolution with a dot matrix of 24 by 40 (totaling 960 dots per character) compared to the more common 5 by 7 matrices. This enhanced quality was made possible by IBM’s microelectronic technology. The print head moved from left to right for each line while the paper advanced during the head’s return movement. Despite being relatively slow by later standards, it exceeded typical typing speeds and could simultaneously print letters and addressed envelopes to streamline mail preparation. The magnetic card feeder could hold up to 200 control and document cards, allowing for prolonged unattended operation.
Models
Two variants were available:
- 6640-001: Released in June 1976, this version printed at speeds up to 92 characters per second and was discontinued on November 1, 1982.
- 6640-002: Introduced in 1979 with double the speed of its predecessor at 184 characters per second; it was also withdrawn on November 1, 1982.
Replacement product
No direct successor was introduced. Although IBM and Diconix developed continuous inkjet printers afterward, these products did not achieve commercial success due to their high cost and complexity. Furthermore, their reliability lagged behind that of daisywheel printers, which limited their acceptance in the market.