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US4580235A Expired / Lapsed US ⏱️ 0.0 years remaining

Electronic calculator with check function

Assignee: Casio Computer Co Ltd
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Filing: 1983-05-26
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Granted: 1986-04-01
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Expires: 2003-05-26
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Abstract

Abstract An electronic calculator with a check function has at least two display parts. A calculating formula inputted with keys is continuously indicated on one display part. At the same time, operated result data corresponding to the data indicated on the one display part is indicated on the remaining display part. Some data of the inputted calculating formula may be amended during the display and replay of the formula, and the corrected final result data is indicated on the display.

Inventors

  • 👤 Mikio Yanagawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:45
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/0227; G06F15/00; G06F15/02

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 133 words
An electronic calculator with a check function comprising: key input means including numerical keys for inputting numerical data, and function keys for inputting function data for instructing arithmetic operations; memory means for successively storing a calculating formula including numerical data and function data inputted by key operations in said key input means; arithmetic operating means for executing an operation of said stored calculating formula; and at least first and second display means, said first display means including means for displaying said calculating formula stored in said memory means, and said second display means including means for displaying an operated result in said arithmetic operating means; and said key input means further including replay key means which are operable for successively reading out said numerical data and function data stored in said memory means.
Claim 2
Dependent Claim 133 words
An electronic calculator with a check function comprising: key input means including numerical keys for inputting numerical data, and function keys for inputting function data for instructing arithmetic operations; memory means for successively storing a calculating formula including numerical data and function data inputted by key operations in said key input means; arithmetic operating means for executing an operation of said stored calculating formula; and at least first and second display means, said first display means including means for displaying said calculating formula stored in said memory means, and said second display means including means for displaying an operated result in said arithmetic operating means; and said key input means further including replay key means which are operable for successively reading out said numerical data and function data stored in said memory means.
Claim 3
Dependent Claim 17 words
The electronic calculator of claim 1, wherein said first display means comprises at least one display stage.
Claim 4
Dependent Claim 74 words
The electronic calculator of claim 1, wherein said replay key means includes: a first replay key which is operable for successively reading out said numerical data and function data stored in said memory means, in an order in which that have been stored; and a second replay key which is operable for successively reading out said numerical data and function data stored in said memory means, in an order reverse to the first-mentioned order.
Claim 5
Dependent Claim 58 words
The electronic calculator of claim 1, including means for displaying said calculating formula including numerical data and function data successively read out each time said replay key means is operated on said first display means; and means for displaying an operated result corresponding to said calculating formula displayed on said first display means, on said second display means.
Claim 6
Dependent Claim 95 words
The electronic calculator of claim 4, wherein said key input means comprises at least one amendment key which is operable for amending contents of said memory means in correspondence with a corrected content when a desired place of the calculating formula displayed on said first display means has been corrected by operation of said at least one amendment key; and wherein said arithmetic operating means includes means for calculating an amended final result data of the calculating formula stored in said memory means, after said amendment is made by said at least one amendment key.
Claim 7
Dependent Claim 49 words
The electronic calculator of claim 5, including means for displaying said final result data calculated by said arithmetic operating means on said second display means; and means for displaying interim result data of an operation in the calculating formula displayed and replayed till then, on said first display means.
Claim 8
Dependent Claim 42 words
The electronic calculator of claim 5, including means for displaying said final result data calculated by said arithmetic operating means is displayed on said second display means; and means for displaying the calculating formula including amendment data, on said first display means.

References Cited (Backward Citations)

US4177520A Cited
US4217656A Cited
US4138734A Cited
US4301511A Cited
US4386412A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-03-31 1989-09-30 1990-04-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-03-31 1993-09-30 1994-04-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-03-31 1997-09-30 1998-04-01 $7700.00 Window Closed / Lapsed

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