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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 = '267') ORDER BY assigned_to ASC, date, patent, type

Total of 4 patents found where: Class is '425'; Subclass is '267';

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T / S Patent Date Description Patentee Category Assigned To
 Henry Lewis Doulton
U 1,193,185 August 1, 1916 Machine for Internally Shaping Telegraph Insulators and the Like
Machine to cut out and shape the internals of an insulator
PODMORE, William
Press 1/2 to Henry Lewis Doulton
 The Ohio Brass Co.
U 1,937,184 November 28, 1933 Jigger
Jiggering machine using centrifugal force to cut out the interior of bushings
AUSTIN, Arthur O.
Manufacturing The Ohio Brass Co.
 The Porcelain Insulator Corp.
U 1,553,356 September 15, 1925 Machine for Producing Threads or Grooves in Plastic Articles
Threading method whereby mandrel rotates (similar to Lapp wobbler method)
BENNETT, Cornelius Van Dyke
Thread The Porcelain Insulator Corp.
U 1,567,027 December 29, 1925 Insulator Threading Machine
Machine to form threads in plastic clay
BENNETT, Cornelius Van Dyke
Press The Porcelain Insulator Corp.

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