公开(公告)号：US3575656A

公开(公告)日：1971-04-20

申请号：US3575656D

申请日：1968-08-30

Applicant: ITE IMPERIAL CORP

Inventor： WATROUS WARD W JR

IPC: H01H33/668 ,  H01J41/06 ,  G01N27/62

CPC classification number: H01H33/668 ,  H01J41/06

Abstract: Method and apparatus for measuring pressure in vacuum interrupters in which electrical connection to the metallic shield provided within the interrupter is not available. Transverse electrostatic and electromagnetic fields are generated within the interior of the vacuum interrupter so as to cause stray electrons within the interior space of the vacuum interrupter to travel in cycloidal or elliptical paths. The tortuous route assumed by the electrons greatly enhances the propability of an ionizing collision The pressure measurements are taken by measuring the number of positive ions collected at the negative electrode and comparing the measurement to a calibration chart on which pressure versus current has been plotted. The measurements may be taken by measuring the time required to charge a capacitor whose charging rate is determined by the vacuum interrupter resistance which is the unknown quantity being measured.