Search the Insulator Patent Reference Library:

Build your search criteria. The patent must match all the values specified.
Select patent types: Utility   Design   Reissue
Patent number:
Date:
Year between: and
Patentee starting with:
City:
State:
Assigned To starting with:
Description containing:
Category:
Class:    Subclass:
Click Search when complete:
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') AND (category.subclass = '211') ORDER BY date ASC, patent, type

Total of 1 patents found where: Class is '409'; Subclass is '211';

View a patent by clicking on the patent number. You can sort by any of the columns by clicking on the column name.

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.

Total of 0.00 seconds