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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent WHERE (category = 'Plunger') ORDER BY date ASC, patent, type

Total of 7 patents found where: Category is 'Plunger';

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T / S Patent Date Description Patentee Category Assigned To
 1872
U Specimen known 132,214 October 15, 1872 Improvement in Formers for Segmentally Screw Threaded Insulators
Plunger to form segmented threads
OAKMAN, Samuel
Plunger  
U Specimen known 132,215 October 15, 1872 Improvement in Formers for Segmentally Screw Threaded Insulators
Plunger to form segmented threads
OAKMAN, Samuel
Plunger  
 1879
U 215,516 May 20, 1879 Improvement in Devices for Attaching Plungers to Glass Presses
Means of attaching a plunger to a glass press using a chuck. (This is known as the ""Gill Chuck"" and may have been used in insulator production, it is not known if Gill was employed by Hemingray at the time of this patent.)
GILL, James G.
Plunger  
 1903
U 735,429 August 4, 1903 Insulator Machine
Plunger for press
WATERS, James
Plunger  
 1909
U Specimen known 913,212 February 23, 1909 Insulator Mold
Plunger for press formed segmented threads in pinhole
JOHNSON, Chauncey C.
Plunger 9/20 to John Watson
 1915
U 1,157,612 October 19, 1915 Die for Insulators
Plunger to form suspension petticoats and threaded pinhole
BENNETT, Cornelius Van Dyke
Plunger Locke Insulator Mfg. Co.
 1916
U 1,198,732 September 19, 1916 Plunger for Forming Insulators
Plunger with holes to release pressure (see 838,727 and reissue 12,934)
LOCKE, Louis Peer
Plunger Locke Insulator Mfg. Co.

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