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Analog Computing Component - Limit Stop Rotary

Analog Computing Component - Limit Stop Rotary

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Description
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.
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.
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.
References:
A.B. Clymer, "The Mechanical Analog Computers of Hannibal Ford and William Newell," Annals of the History of Computing, 15, #2, 1993, 19-34.
Accession file.
Location
Currently not on view
Object Name
analog computing component
maker
Ford Instrument Company
place made
United States: New York, Queens, Long Island City
Physical Description
aluminum (frame material)
iron (gears, shafts material)
Measurements
overall: 9 cm x 5.2 cm x 5 cm; 3 17/32 in x 2 1/16 in x 1 31/32 in
ID Number
1982.0751.11
catalog number
1982.0751.11
accession number
1982.0751
Credit Line
Ford Instrument Company, Division of Sperry Rand Corporation
subject
Mathematics
See more items in
Medicine and Science: Mathematics
Data Source
National Museum of American History
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