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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') AND (category.subclass = '180') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '221'; Subclass is '180';

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T / S Patent Date Description Patentee Category Assigned To
 1926
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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