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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 = '221') ORDER BY date ASC, patent, type

Total of 5 patents found where: Class is '221';

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T / S Patent Date Description Patentee Category Assigned To
 1920
U 1,342,053 June 1, 1920 Bushing Forming Machine
Machine to manufacture wall tubes and bushings
MCKNIGHT, Oscar W.
Wall Tube Brunt Tile & Porcelain Co.
 1923
U 1,471,907 October 23, 1923 Machine for Heading Porcelain Tubes and the Like
Machine to make porcelain wall tubes
MASON, Albert G.
BUCKLEY, Lorenzo C.
Wall Tube The R. Thomas & Sons Co.
 1924
U 1,512,430 October 21, 1924 Machine for Assembling Nail Knobs
Machine for assembling nail-knobs
LOY, John G.
Knob Federal Porcelain Co.
 1926
U 1,589,939 June 22, 1926 Nail Knob Assembly
Machine to manufacture nail-knobs
CASE, Francis M.
Knob Federal Porcelain Co.
U 1,589,940 June 22, 1926 Nail Knob Assembling and Securing Machine
Machine to manufacture nail-knobs
CASE, Francis M.
Knob Federal Porcelain Co.

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