Patent ID: 7918139
Filing Date: 2011-04-05
Classification: G01L

Abstract:
1. A Pirani vacuum gauge comprising a heat filament of metal wire, a support unit for supporting said heat filament and an elongated container for defining an air sealed space when the gauge is coupled to a chamber to be measured for pressure and accommodating said heat filament and said support unit in the air sealed space, wherein one end of said container is provided with a coupling end which couples the gauge to a chamber to be measured for pressure and the other end of said container is provided with a means which electrically connects said heat filament and said support unit to an external control circuit with holding said heat filament and said support unit in an air sealing to an atmosphere, and said heat filament and said support unit extend within said elongated container in a longitudinal direction from the one end to the other end of said container, wherein a body of said container is formed of metal material, a first bore and a second bore longitudinally extend through the body of said container, the first bore and second bore accommodating respectively said heat filament and said support unit, and the coupling end to the chamber to be measured for pressure is an end of said body which has a recess space dented toward the inside of said container and one end of said heat filament and one end of said support unit are jointed in the recess space.