Analog Computing Component - Spur Gear Differential
date: label: date made
content: 1920s
name: label: maker
content: Ford Instrument Company
notes: label: Description
content: This spur gear differential was built by Ford Instrument Company during the 1920s and generally used for addition and subtraction on the company’s range keepers and computers. It includes two brass gears on a steel shaft that are separated by a brass planetary frame. The frame carries two sets of two small, linked gears, with one gear in each set linked to each of the larger gears. According to the accession file, the object contains miniature bearings where the balls ride on a hardened shaft rather than on the usual inner race.
label: Description
content: References:
label: Description
content: A.B. Clymer, "The Mechanical Analog Computers of Hannibal Ford and William Newell," <I>Annals of the History of Computing</I>, 15, #2, 1993, 19-34.
label: Description
content: Accession file.
label: Description
content: K.C. Epstein, <I>Analog Superpowers: How Twentieth Century Technology Theft Built the National Security State<I>, Chicago and London: University of Chicago Press, 2024.
label: Location
content: Currently not on view
place: label: place made
content: United States: New York, Queens, Long Island City
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
creditLine: label: Credit Line
content: Ford Instrument Company, Division of Sperry Rand Corporation
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1982.0751.26
label: catalog number
content: 1982.0751.26
label: accession number
content: 1982.0751
objectType: label: Object Name
content: analog computing component
physicalDescription: label: Physical Description
content: brass (gears, frame material)
label: Physical Description
content: steel (shaft material)
label: Measurements
content: overall: 2.7 cm x 6.5 cm x 3.7 cm; 1 1/16 in x 2 9/16 in x 1 15/32 in