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SELECT DISTINCT patent.*, YEAR(date) as year FROM patent LEFT JOIN category ON category.patent = patent.patent AND category.type = patent.type WHERE (category.class = '409') ORDER BY date ASC, patent, type

Total of 4 patents found where: Class is '409';

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T / S Patent Date Description Patentee Category Assigned To
 1912
U 1,022,874 April 9, 1912 Machine for Drilling Porcelain
Machine for drilling U-shaped holes in Hewlett suspension disk
RIDDELL, John
Suspension General Electric Co.
 1916
U 1,191,595 July 18, 1916 Machine for Forming Porcelain Ware
Machine to cut out and shape the Hewlett suspension disk
HEWLETT, Edward M.
Suspension General Electric Co.
 1939
U 2,181,810 November 28, 1939 Glass Block Trimmer
Trimmer to remove excess bonding agent from glass blocks
HAWK, Charles E.
OI Owens-Illinois Glass Co.
 1944
U 2,355,684 August 15, 1944 Insulator Cutting Machine
Machine to automatically trim the profile in insulators in an assembly line process
SKIPPER, Edward M.
Machine Locke Insulator Corp.

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