Knapp dry-contact rectifier
date: label: date made
content: ca 1927
name: label: maker
content: Knapp Electric
notes: label: Description (Brief)
content: Marked: "Made Expressly for / Knapp Electric Corporation / Port Chester, N.Y. / Patent No. 1649741 Other Pats. Pending". Unit has 17 copper fins, each 1.75" square. Five lugs on insulated strip are for circuit connections. US Patent 1649741 for "Electric Current Rectifier," issued to Samuel Ruben, 15 November 1927. Ruben later created a line of mercury cell batteries and with Phillip Mallory founded the company that became Duracell.
label: Location
content: Currently not on view
setName: label: See more items in
content: Work and Industry: Electricity
creditLine: label: Credit Line
content: from Franklin Wingard
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: EM.322012
label: patent number
content: 1649741
label: catalog number
content: 322012
label: accession number
content: 241556
objectType: label: Object Name
content: rectifier
physicalDescription: label: Measurements
content: overall: 2 3/8 in x 3 7/8 in x 2 1/2 in; 6.0325 cm x 9.8425 cm x 6.35 cm