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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 = '425') AND (category.subclass = '152') ORDER BY date ASC, patent, type

Total of 2 patents found where: Class is '425'; Subclass is '152';

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T / S Patent Date Description Patentee Category Assigned To
 1923
U 1,469,584 October 2, 1923 Tube Forming Machine
Machine for making porcelain wall tubes		 CASE, Francis M.
 Wall Tube Federal Porcelain Co.
 1947
U 2,415,462 February 11, 1947 Ceramic Molding Press
Vacuum molding of clay articles such as insulators. This may be the patent used by Locke to make their ""vacuum dry pressing"" porcelain insulators.		 CHERRY, George L.
VEALE, Charles C.
 Press Western Electric Co.

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