Patent US4064399A successfully refreshed from Google Patents.
US4064399A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic calculator having keyboard for entering data
Assignee: NEC Corp
•
Filing: 1976-03-31
•
Granted: 1977-12-20
•
Expires: 1996-03-31
Abstract
Abstract An electronic calculator comprises a semiconductor integrated circuit and an input keyboard which includes the series connection of a condition switch and an operation key, thereby minimizing the number of interconnections between the semiconductor integrated circuit and the keyboard.
Inventors
- 👤 Susumu Muranaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:58
CPC Classifications
G; G06; G06F; G06F1/00; G06F1/22; G06F3/00; G06F3/01; G06F3/02; G06F3/023
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
128 words
An electronic calculator comprising: a semiconductor integrated circuit having an arithmetic operation circuit, a control circuit and a terminal for receiving command signals for said operation and control circuits; a condition switch for generating a first command signal for said semiconductor integrated circuit, said switch being fixed to continue generating said first command signal once said switch is set to generate said first command signals; and an operation key for generating a second command signal for the calculator to perform a required arithmetic operation; wherein said operation key is connected between said condition switch and said terminal of said semiconductor integrated circuit, and said first and second command signals generated by said condition switch and said operation key are applied to said terminal of said semiconductor integrated circuit.
Claim 2
Dependent Claim
128 words
An electronic calculator comprising: a semiconductor integrated circuit having an arithmetic operation circuit, a control circuit and a terminal for receiving command signals for said operation and control circuits; a condition switch for generating a first command signal for said semiconductor integrated circuit, said switch being fixed to continue generating said first command signal once said switch is set to generate said first command signals; and an operation key for generating a second command signal for the calculator to perform a required arithmetic operation; wherein said operation key is connected between said condition switch and said terminal of said semiconductor integrated circuit, and said first and second command signals generated by said condition switch and said operation key are applied to said terminal of said semiconductor integrated circuit.
Claim 3
Dependent Claim
27 words
An electronic calculator of claim 1, wherein said condition switch is a point switch used to determine the decimal place in the display of the calculation results.
Claim 4
Dependent Claim
19 words
An electronic calculator of claim 1, wherein said condition switch is an accumulation switch used to accumulate calculation results.
Claim 5
Dependent Claim
19 words
An electronic calculator of claim 1, wherein said condition switch is a rounding switch used to round calculation results.
Claim 6
Dependent Claim
22 words
An electronic calculator of claim 1, wherein said condition switch is a constant switch for conditioning the calculator to perform constant calculations.
Claim 7
Dependent Claim
30 words
The electronic calculator of claim 1, wherein said condition switch has several fixed contacts and one moving contact, said moving contact always being connected to one of said fixed contacts.
Claim 8
Dependent Claim
57 words
In combination in an electronic calculator, condition switch means having plural inputs, a common ouput, and means for connecting one of said inputs with said output, a calculator integrated circuit having an input terminal, and an operation key connected between said common output of said condition switch means and said input terminal of said calculator integrated circuit.
Claim 9
Dependent Claim
57 words
In combination in an electronic calculator, condition switch means having plural inputs, a common ouput, and means for connecting one of said inputs with said output, a calculator integrated circuit having an input terminal, and an operation key connected between said common output of said condition switch means and said input terminal of said calculator integrated circuit.
Claim 10
Dependent Claim
56 words
A combination as in claim 7 wherein said integrated circuit further comprises plural multiple input coincidence logic gates each having a first input connected to said integrated circuit input terminal, and means for supplying time separated pulses to said plural inputs of said condition switch means and to second input terminals of said coincidence logic gates.
Claim 11
Dependent Claim
23 words
A combination as in claim 8 further comprising disjunctive logic gate means connected to said coincidence logic gates for producing an operation signal.
Claim 12
Dependent Claim
30 words
A combination as in claim 9 further comprising plural storage means each connected between an input of said disjunctive logic means and a different one of said coincidence logic gates.
Claim 13
Dependent Claim
24 words
A combination as in claim 7 further comprising plural function keys having output terminals connected to said input terminal of said calculator integrated circuit.
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) | 1980-12-19 | 1981-06-20 | 1981-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-19 | 1985-06-20 | 1985-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-19 | 1989-06-20 | 1989-12-20 | $7700.00 | Window Closed / Lapsed |