Abstract: 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-energy rate conversion mode based upon a selected fuel meter dial and Metric or English units. In addition, a Fahrenheit-to-centigrade conversion and a centigrade-to-Fahrenheit conversion functions are incorporated. The calculator includes a keyboard 18, a microprocessor 16, a timer 26, a power source 12, a switch 14 and a display screen 22.
Type:
Grant
Filed:
March 7, 1991
Date of Patent:
May 11, 1993
Assignees:
John M. Winslow, Henry D. Winslow
Inventors:
John M. Winslow, Henry D. Winslow, Walter Rubinstein