Number | Name | Date | Kind |
---|---|---|---|
2622160 | Werner | Dec 1952 | |
3392592 | Waldorf et al. | Jul 1968 | |
3626120 | Wright | Dec 1971 | |
3711685 | Castle | Jan 1973 | |
3863748 | Trezise | Feb 1975 | |
3882295 | Madland | May 1975 | |
4010838 | Sims, Jr. | Mar 1977 | |
4071719 | Madland | Jan 1978 |
Number | Date | Country |
---|---|---|
304088 | Feb 1918 | DE2 |
Entry |
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Harris, Electronic Keyboard Shiftlock Mechanism, IBM Technical Disclosure Bulletin, vol. 20, No. 10, p. 4037, 3/78. |
Crome, Electronic Keyboard Shiftlock Mechanism, IBM Technical Disclosure Bulletin, vol. 20, No. 1, p. 258, 6/77. |