1
Charles J Faget: Hand-held portable calculator assembly. David L Ray, Edgar E Speilman Jr, August 28, 1979: US04165554 (80 worldwide citation)

A hand-held, portable, electronic calculator assembly including a body with a gripping and covering member for making the calculator fully operable by the user with one hand and for covering the keyboard of the calculator to prevent damage to the keyboard or depression of the keys when not in use. T ...


2
John M Winslow, Henry D Winslow, Walter Rubinstein: Portable calculator for refrigeration heating and air conditioning equipment service. John M Winslow, Henry D Winslow, Krass & Young, May 11, 1993: US05209400 (65 worldwide citation)

A calculator apparatus 10 includes the standard calculator mode and several other modes functions namely; a pressure-temperature conversion, a temperature-to-pressure conversion based on refrigerant, a relative humidity reading based on input of the dry bulb and wet bulb temperature; and a flow-ener ...


3
Adolf H Zielinski: Portable calculator. Olson Trexler Wolters Bushnell & Fosse, January 11, 1977: US04002892 (56 worldwide citation)

A portable electronic calculator is provided with a housing carrying a first printed circuit board having the operating parts mounted thereon, i.e., keyboard, electronic arithmetic unit, and multi-digit display unit. The housing is of rectangular outline and of shallow height, and is provided at one ...


4
Stephen A Roen: Solar powered portable calculator. Litton Business Systems, Stephen A Roen, Norman Friedman, Robert F Rotella, April 12, 1977: US04017725 (45 worldwide citation)

A portable calculator utilizing a solar panel array which can be either slidably moved within the calculator's housing or pivotly connected to it and which when exposed to incident light provide power for the calculator.


5
Ritsuko Sakai: Portable food-constituent-amount display and calculating system, and device to operate the system. Browdy and Neimark, August 8, 1989: US04855945 (16 worldwide citation)

A portable system gives information on the amounts of constituents of foods for health control. The system tells the amounts of nutritive constituents of foods and the total amount of nutritive constituents of foods taken a day by arithmetic operations, and determines excessive or insufficient amoun ...


6
Paul Nachtigal: Combination calculator and time billing device. David S Woronoff, August 7, 1979: US04164038 (16 worldwide citation)

A portable calculator is adapted to provide a time billing function and a calculating function. A "stop watch" function is actuated to start the billing period and stop the billing period attributable to a particular account. A memory stores the accumulated billing time for the particular account un ...


7
Reiji Hirano, Takayoshi Hanakata, Matsutoshi Ito: Printing control device. Canon Kabushiki Kaisha, Fitzpatrick Cella Harper & Scinto, January 25, 1977: US04004672 (11 worldwide citation)

A printer for use with a portable calculator, a handy typewriter or the like is provided with a printing control device which comprises a control circuit for controlling the operation of a stepping motor to feed a recording medium. In order to control the motor, the control circuit generates a serie ...


8
Michael J Cochran, Jerry L Vandierendonck: Expandable function electronic calculator. Texas Instruments, October 5, 1976: US03984816 (9 worldwide citation)

An electronic portable calculator implemented in MOS/LSI technology and including a scanned keyboard input and display output. The calculator system utilizes a plurality of output terinals on the primary MOS/LSI chip for selectively addressing in timed coded sequence an array of peripheral MOS/LSI c ...


9
Lawrence K Howard: Printing calculator. Roger A Marrs, January 6, 1987: US04635219 (8 worldwide citation)

A portable calculator and recordal device is disclosed herein which includes a pad of paper and an electronic calculator which is movably disposed over the pad on a sliding carriage in association with a printer whereby information entered into the calculator may be printed onto the paper. The slidi ...


10
Trevor O Jones: Portable calculator incorporating an anti-theft feature. General Motors Corporation, Albert F Duke, April 14, 1981: US04262337 (8 worldwide citation)

A portable calculator which includes circuitry for disabling operation of the display until a predetermined sequence of digits are entered from the keyboard. The circuitry includes a plurality of latches which are set in sequence in response to application of power to the calculator. The setting of ...