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Class 218/109 - Valve (e.g., spring biased valve plate)


Subclass of Class 218 - High-voltage switches with arc preventing or extinguishing devices
Definition: Subject matter wherein a movable cover or lid which regulates
No. of patents: 2
Last issue date: 04/04/2000


NumberTitleIssue Date
6046423Switchgear
In a switchgear, by using a spring with a varying spring constant from closing to electrode opening as a loading spring, spring load in the opened electrode state is made smaller than a spring load in the closed electrode state to decrease the energy requ... 		04/04/2000
5296662Electric switching device
An electric switching device according to the invention comprises two fixed contacts and one movable contact, referred to jointly as the main contact system. The main contact system is located in an oil-insulated cavity enclosed in a housing. In its direc... 		03/22/1994
 
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