This compilation Copyright (C) 2005 Mike Sebastian. No copyright claim is made to original U.S. Government works.
| U.S. Patent No. | Assignee | File Date | Issue Date | Inventor1 | Product | Title | Comments |
| 3233225 | Keinzle Apparate G.m.b.H. | April 21, 1960 | February 1, 1966 | Kassel | - | Programming arrangement for electronic accounting machines | - |
| 3280315 | Bell Punch Co. Ltd. | September 6, 1957 | October 18, 1966 | Kitz | Anita Mk VII? | Key controlled decimal electronic calculating machine | - |
| 3328763 | Monroe International, Inc. | October 1, 1963 | June 27, 1967 | Rathbun | - | Electronic desk-type computer | - |
| 3330946 | Wyle Laboratories | October 7, 1963 | July 11, 1967 | Scuitto | - | Calculator apparatus | Electronic desk calculator |
| 3348215 | SCM Corp. | December 27, 1961 | October 17, 1967 | Soule | - | Magnetic drum memory and computer | Calculator circuits incorporated into typwriter for accounting transaction; typwriter prints results |
| 3353008 | Bell Punch Co. Ltd. | May 1, 1961 | November 14, 1967 | Kitz | Anita Mk VII? | Calculating machine using pulse actuated counters | - |
| 3375356 | Wyle Laboratories | June 12, 1964 | March 26, 1968 | Scuitto | - | Calculator decimal point alignment apparatus | - |
| 3375498 | Wyle Laboratories | May 18, 1964 | March 26, 1968 | Scuitto | - | Calculating apparatus for distinguishing meaningful digits | Leading and trailing zero suppression |
| 3388384 | General Micro-Electronics Inc. | March 8, 1966 | June 11, 1968 | Bogert | - | Zero suppression circuit | Leading and trailing zero suppression |
| 3391391 | IBM | September 24, 1965 | July 2, 1968 | Simpson | - | Computation with variable fractional point readout | - |
| 3402285 | Wang Laboratories | September 22, 1964 | September 17, 1968 | Wang | - | Calculating apparatus | Calculator with logarithm function |
| 3405392 | Sperry Rand Corp. | April 30, 1965 | October 8, 1968 | Milne | - | Electronic calculators | - |
| 3406625 | Friden, Inc. | February 18, 1966 | October 22, 1968 | Chamness | Singer/Friden 1152 | Driving means for high-speed printing apparatus | - |
| 3428950 | Wang Laboratories | March 22, 1966 | February 18, 1969 | Chang | - | Programmable calculating apparatus | Rounding of displayed result without altering values in memory |
| 3432845 | IBM | March 8, 1966 | March 11, 1969 | Douglas | - | Numeric display | Zero suppression, grouping by 3-digits, decimal points |
| 3447136 | Philco-Ford Corp. | October 18, 1966 | May 27, 1969 | Bogert | - | Aperiodic arithmetic calculator | - |
| 3453601 | Philco-Ford Corp. | October 18, 1966 | July 1, 1969 | Bogert | - | Two speed arithmetic calculator | Dual clock rate to reduce power consumption |
| 3465296 | (none) | February 26, 1965 | September 2, 1969 | Drage | - | Plural registers in a calculating machine | - |
| 3474439 | Philco-Ford Corp. | October 18, 1966 | October 21, 1969 | Miner | - | Character and decimal point generator | Stroked vector numeric CRT display for serial arithmetic calculator or computer |
| 3487369 | Logicon Inc. | August 12, 1966 | December 30, 1969 | King | - | Electronic calculator | - |
| 3492656 | Telefunken | April 2, 1966 | January 27, 1970 | Hildebrandt | - | Zero reproduction in calculators | Two binary codes for zero - one for numerical zero and the other for unused positions in a buffer, to facititate zero suppression |
| 3492658 | Telefunken | January 16, 1968 | January 27, 1970 | Klett | - | Electronic desktop calculator | - |
| 3495221 | Friden, Inc. | November 13, 1967 | February 10, 1970 | Herendeen | Singer/Friden 1152 | Data detection | Register usage indicator |
| 3495222 | Olivetti | March 2, 1964 | February 10, 1970 | Perotto | Programma 101 | Program controlled electronic computer | Programmable desktop calculator with magnetic card program storage |
| 3502787 | Barry Wright Corp. | June 27, 1966 | March 24, 1970 | Reach | Mathatron | Electrical component leads | - |
| 3509329 | Wang Laboratories | October 24, 1966 | April 28, 1970 | Wang | Wang 300 series | Calculator | Separate keyboard/display and electronics units; uses constants for logarithms |
| 3518629 | Computron Corp. | February 6, 1964 | June 30, 1970 | Frankel | SCM Marchant Cogito 240SR | Recirculating memory timing | - |
| 3523282 | Friden Inc. | October 28, 1963 | August 4, 1970 | Ragen | - | Calculator | - |
| 3524970 | Wang Laboratories | September 22, 1964 | August 18, 1970 | Wang | - | Automatically controlled calculating apparatus | Punched card storage for programs; discussion of logarithm algorithm and program opcodes |
| 3526760 | Singer Company | April 1, 1966 | September 1, 1970 | Ragen | Friden EC-132 | Square root calculator employing a modified sum of the odd integers | - |
| 3526887 | Singer Company | June 30, 1967 | September 1, 1970 | Erni | - | Digit order and decimal point display system and circuit therefor | For calculators without a numeric display, a row of lamps light to indicate entry of whole numbers, the decimal point, and fractional numbers |
| 3537073 | Sony | December 16, 1965 | October 27, 1970 | Sakoda | - | Number display system eliminating futile zeros | Zero suppression scheme |
| 3546676 | Singer Company | October 29, 1963 | December 8, 1970 | Ragen | Friden EC-130 | Calculator | First transistorized calculator |
| 3553445 | SCM Corp. | August 22, 1966 | January 5, 1971 | Hernandez | SCM Marchant Cogito 240SR | Multicipher entry | Automatic spacing between groups of three digits |
| 3566097 | Telefunken | March 17, 1966 | February 23, 1971 | Hildebrandt | - | Electronic calculator utilizing delay line storage and interspersed serial code | - |
| 3588841 | Singer Company | March 27, 1969 | June 28, 1971 | Ragen | Singer/Friden 1152 | Programmable electronic calculator | - |
| 3593313 | Computer Design Corporation [Compucorp] | December 15, 1969 | July 13, 1971 | Tomaszewski | Monroe 1665 | Calculator apparatus | Early Compucorp design |
| 3597600 | Singer Company | May 5, 1969 | August 3, 1971 | Herendeen | Friden 1160 | Electronic desk top calculator having a dual function keyboard logic means | Combined RPN enter/change-sign key; first depression is an enter, second depression is a change-sign |
| 3612846 | Bell Punch Co. Ltd. | February 17, 1969 | October 12, 1971 | Drage | - | Calculating machines with control circuits to enter first number | - |
| 3622768 | SCM Corp. | August 28, 1969 | November 23, 1971 | Clark | SCM Cognito 412 | Dual key depression for decimal position selection | - |
| 3623009 | Singer Company | November 18, 1968 | November 23, 1971 | Ragen | Singer/Friden 1152 | Electronic printing calculator | Lower cost printing calculator |
| 3629564 | Bell Punch Co. Ltd. | February 17, 1969 | December 21, 1971 | Drage | - | Calculating machines with a constant function key | - |
| 3641501 | Bell Punch Co. Ltd. | March 31, 1966 | February 8, 1972 | Lloyd | - | Calculating machines | Memory-display register exchange |
| 3646544 | Sanyo | May 6, 1969 | February 29, 1972 | Yamaguchi | - | Apparatus for indicating numerical information | Seven-segment incandescent display; negative sign floats immediately to the left of most significant digit |
| 3654612 | Takachiho Koeki Kabushiki Kaisha | March 29, 1969 | April 4, 1972 | Ohara | Descal ASI-500 | Display system using a cathode-ray tube | - |
| 3662346 | Sanyo | February 15, 1969 | May 9, 1972 | Tada | - | Information output system | Leading and trailing zero suppression for shift-register display buffer |
| 3683371 | Burroughs Corp. | September 15, 1970 | August 8, 1972 | Holz | - | Magnetic keyboard terminal | Not reed switches |
| 3685041 | Burroughs Corp. | May 12, 1970 | August 15, 1972 | Kondur | - | Decimal to binary encoder for generating decimal point position and round-off information in a calculator | - |
| 3715746 | Omron Tateisi Electronics, Co. | March 10, 1971 | February 6, 1973 | Hatano | - | Keyboard input device | Row driver circuit, columns are digit lines |
| 3720820 | Tektronix | March 18, 1971 | March 13, 1973 | Cochran | - | Calculator with a hierarchy control system | - |
| 3725873 | Singer Company | May 11, 1964 | April 3, 1973 | Hare | Friden EC-130 | Calculator having sequential access stack | RPN 4-register stack |
| 3755806 | Bomar/Ali Inc. | May 24, 1972 | August 28, 1973 | Bunting | - | Calculator display circuit | Uses TI TMS0103 chip; display blanking circuit to save battery power |
| 3757097 | SCM Corp. | March 29, 1971 | September 4, 1973 | Kuijsten | SCM Marchant I | Extra bit for floating decimal control and correction of false intermediate arithmetic results | Simplification of circuitry by adding 5th bit to BCD representation for decimal point/scaling of floating point numbers |
| 3760171 | Wang Laboratories | January 12, 1971 | September 18, 1973 | Wang | Wang 720C | Programmable calculators having display means and multiple memories | - |
| 3760363 | Bell Punch Co. Ltd. | July 29, 1969 | December 18, 1973 | Drage | - | Calculating machines with a copy routine | Storage register copy function |
| 3760370 | Tektronix | April 26, 1971 | September 18, 1973 | Cochran | - | Calculator with number processing system | - |
| 3761918 | Omron Tateisi Electronics, Co. | March 10, 1970 | September 25, 1973 | Hatano | - | Concurrent entry preventing system | Blocks accidental multi-key presses |
| 3796843 | Bomar Instrumentation Corp. | January 2, 1973 | March 12, 1974 | Durkee | - | Calculator keyboard switch with disc spring contact and printed circuit board | Various early calculators |
| 3800129 | Electronic Arrays, Inc. | December 28, 1970 | March 26, 1974 | Umstattd | ICM 816 | Mos desk calculator | Five chip calculator |
| 3831081 | Melcor Electronics Corp. | March 2, 1973 | August 20, 1974 | Weiss | - | Miniature calculator having push-button on-off switch | Electronic on-off switching of calculator with single key |
| 4045636 | Bomar Instrument Corp. | January 28, 1976 | August 30, 1977 | Yoder | - | Keyboard switch assembly having printed circuit board with plural layer exposed contacts and undersurface jumper connections | Screen printed jumpers printed over insulated layer for single-sided PCB for keyboard |
Last updated November 5, 2006
