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Hand-held calculator for performing calculations in feet, inches and fractions

  • US 4,488,250 A
  • Filed: 07/02/1982
  • Issued: 12/11/1984
  • Est. Priority Date: 07/02/1982
  • Status: Expired due to Term
First Claim
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1. A portable hand-held electronic calculator for feet, inch, and fraction calculations, said calculator having a housing containing a display, numerical keys, functional keys, and means operatively connected to said numerical and functional keys for performing a plurality of predetermined computations based upon which keys are pressed, said performing means being operatively connected to said display for displaying the results of said computations, said calculator comprising:

  • field keys interconnected with said performing means, said field keys comprising each of the following input keys;

    (a) a feet input key,(b) an inch input key,(c) a plurality of fraction input keys of a predetermind series of fractions where the numerator is preselected from said numerical keys, each of said input keys being capable of selective manual activation,means in said display for indicating feet, inches, and fractions, andmeans in said performing means receptive of a number from said numerical keys and then responsive to the selective manual activation of any one of said input keys in said field keys for displaying the aforesaid number in the selected feet, inches, or fractions in said display with said indications, said performing means being further capable of determining said computations of feet, inches, and fractions.

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