Analog Computing Component - Limit Stop Rotary
date: label: date made
content: ca 1920-1955
name: label: maker
content: Ford Instrument Company
notes: label: Description
content: This mechanism was manufactured by Ford Instrument Company for use in analog computing devices such as range keepers and its computers. Called a “limit stop rotary” it limited the number of revolutions in a gearing line.
label: Description
content: The aluminum base has two shafts mounted on it that both pass through an oval frame piece. Each shaft also carries a gear which has black arm pieces above and below it. One shaft also has a T-shaped aluminum piece atop it. A ring of ball bearings is between the edges of this shaft and this aluminum piece.
label: Description
content: A black mark in ink on the base reads: item 12. A mark on the ball bearing holder reads: FAFNIR USA. A mark on one gear reads: 615430B. A mark on the other gear reads: 615431A. A mark on the edge of the oval frame piece reads: 615661. A mark on the underside of the top frame piece reads: 38-0043 2.
label: Description
content: The precise date of the object is unknown but one might guess the 1930s or later.
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: 1982.0751.11
label: catalog number
content: 1982.0751.11
label: accession number
content: 1982.0751
objectType: label: Object Name
content: analog computing component
physicalDescription: label: Physical Description
content: aluminum (frame material)
label: Physical Description
content: iron (gears, shafts material)
label: Measurements
content: overall: 9 cm x 5.2 cm x 5 cm; 3 17/32 in x 2 1/16 in x 1 31/32 in