Patent US3452615A successfully refreshed from Google Patents.
US3645441A
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US
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Keyboard for a desk computer
Assignee: Olivetti SpA
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Filing: 1969-10-24
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Granted: 1972-02-29
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Expires: 1989-10-24
Abstract
Abstract A calculator, including working registers and one or more accumulating registers, is provided with a keyboard including numerical keys, function keys and a connecting key. The connecting key, when operated, connects a selected accumulating register with a predetermined working register controlled by the function keys. The number contained in the selected accumulating register is thereby designated as an operand in the performance of a function selected by the simultaneous or subsequent operation of a function key.
Inventors
- 👤 Giovanni De Sandre
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:11
CPC Classifications
G; G06; G06F; G06F15/00; G06F15/02; G06F15/0225; G06F3/00; G06F3/01; G06F3/02; G06F3/023; G06F3/0238; H; H03; H03M; H03M11/00; H03M11/02; H03M11/04; H03M11/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
178 words
A digital machine for performing mathematical operations on entered numbers comprising a plurality of working registers; at least one accumulating register; a control keyboard comprising three groups of keys, the first group comprising numerical key means for keying in digits, decimal point and algebraic sign, thereby forming an operand in one of said plurality of working registers, the second group comprising function key means for commanding the formatioN of algebraic sums in said accumulating register and for transferring the contents of the accumulating register to a main register of said plurality of working registers and, the third group comprising special function key means for commanding the formation of special functions of the contents of two registers of said plurality of working registers and, a connecting key operable in conjunction with a key of said special function key means, for transferring a number contained in said accumulating register to one of said two working registers thereby designating said number on an operand in the performance of a function selected by an operated key of said special function key means.
Claim 2
Dependent Claim
178 words
A digital machine for performing mathematical operations on entered numbers comprising a plurality of working registers; at least one accumulating register; a control keyboard comprising three groups of keys, the first group comprising numerical key means for keying in digits, decimal point and algebraic sign, thereby forming an operand in one of said plurality of working registers, the second group comprising function key means for commanding the formatioN of algebraic sums in said accumulating register and for transferring the contents of the accumulating register to a main register of said plurality of working registers and, the third group comprising special function key means for commanding the formation of special functions of the contents of two registers of said plurality of working registers and, a connecting key operable in conjunction with a key of said special function key means, for transferring a number contained in said accumulating register to one of said two working registers thereby designating said number on an operand in the performance of a function selected by an operated key of said special function key means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |