line

Patent HP hand-held calculator related patents

line

Below you find a list of the most interesting patents filed by Hewlett Packard related to hand-held calculators. A more extensive overview can be found by following the links at the bottom of this page.

Patent number
(link to pdf file) 		Related model Title of the patent
US 3,719,849 Classic Solid State Display's.
US 3,755,697 Classic Light-Emitting Diode Driver.
US 3,781,820 HP-65 Portable Electronic Calculator.
US 3,855,461 HP-65 Calculator with key code association and display features.
US 3,863,060 HP-80 General purpose calculator with capability for performing interdisciplinary business calculations.
US 3,892,958 HP-65 Inverse/complementary function prefix key.
US 3,893,173 HP-65 Miniaturized magnetic card reader/recorder for use in hand-held calculator.
US 3,941,953 Classic Keyboard having switches with tactile feedback.
US 3,946,218 HP-80 General purpose calculator with capability for performing yield-to-maturity of a bond calculation.
US 3,955,074 HP-80 General purpose calculator having keys with more than one function assigned thereto.
US 3,987,290 Woodstock Calculator apparatus for displaying data in engineering notation.
US 4,001,569 HP-45 General purpose calculator having selective data storage, data conversion and time-keeping capabilities.
US 4,009,379 HP-55 Portable programmable calculator displaying absolute line number addresses and key codes and automatically altering display formats.
US 4,035,627 HP-45 Scientific Calculator.
US 4,037,092 HP-65 Calculator having preprogrammed user-definable functions.
US 4,047,012 HP-45 General purpose calculator having factorial capability.
US 4,055,757 HP-22 Calculator apparatus with annuity switch for performing begin- and end-period annuity calculations.
US 4,059,750 HP-45 General purpose calculator having selective data storage, data conversion and time-keeping capabilities.
US 4,091,270 HP-82153A Electronic calculator with optical input means.
US 4,099,246 HP-65 Calculator having merged key codes.
US 4,143,809 HP-82153A Optical bar code reader.
US 4,177,520 HP-25 Calculator apparatus having a single-step key for displaying and executing program steps and displaying the results.
US 4,197,586 Spice Electronic calculator assembly.
US 4,291,385 HP-65 Calculator heaving merged key codes.
US 4,424,563 HP-85 Data processor including a multiple word processing method and device.
US 4,821,228 HP-28C Method and apparatus for computation stack recovery in a calculator.
US 4,825,395 HP-28C Apparatus with torsionly stressed conductors routed through a hollow articulated hinge.
US 4,845,652 HP-28C Generic equation solver interface for solving mathematical equations.
US 4,852,057 HP-28C Algebraic expression method and implementation for an electronic data processing apparatus.
US 4,868,745 HP-28C Data processing system and method for the direct and indirect execution of uniformly structured object types.
US 4,878,293 HP-28C Method of connecting assemblies using torsionly stressed conductors routed through a hollow articulated hinge.
US 4,885,430 HP-28C Flexible printed circuit assembly with torsionly rotated conductors.
US 4,885,714 HP-28C Calculator having a user-accessible object stack for the uniform application of mathematical functions and logical operations to a multiplicity of object types.
US 5,007,008 HP-48SX Method and apparatus for selecting key action.
US 5,020,012 HP-32S Method and apparatus for matching menu labels with keys.
US 5,025,403 HP-32S Fraction entry and display.
US 5,060,990 Champion Multi-stage door snap.
US 5,075,792 HP-48SX Low power optical transceiver for portable computing devices.
US 5,089,980 HP-32S Double keystroke fraction entry and interface method.
US 5,128,887 HP-32S Numerical accuracy indicator for rounded numeric value display method.
US 5,155,697 HP-48SX Most precise fraction display method.
US 5,175,700 HP-82211A Method and apparatus for solving multiple equations.
US 5,216,627 HP-48SX Method and apparatus for computing with terms having units.
US 5,258,748 HP-48SX Accessing and selecting multiple key functions with minimum keystrokes.
US 5,260,886 HP-48SX Default denominator for fraction entry and display.
US 5,530,234 HP-38G Handheld calculator having a retractable cover.
US 7,337,958 HP-49G Calculator device having a USB connection.

line

HP calculator patents related links:

line