Title:
【発明の名称】熱損失圧力測定装置および方法
Document Type and Number:
Japanese Patent JP2839244
Kind Code:
B1
Abstract:
An improved Pirani gauge has a small-diameter wire sensing element, coplanar with a small-diameter wire compensating element, with two parallel flat thermally conductive plates spaced from the sensing and compensating elements. The sensing (12) and compensating elements (14) and their connections have the same physical dimensions, thermal properties and resistance properties. The connections have large thermal conductances to a uniform temperature region and the elements are located in the same vacuum environment. A DC heating current (32) is used and confined to only the sensing elements (12). A relatively small AC signal (32,40) is used to sense bridge balance. A simplified three-dimensional pressure compensation formula (5) provides accurate compensation while simplifying the collection of calibration data. The improved gauge provides significant advancements in Pirani gauge accuracy, production cost, and package size.
More Like This:
Inventors:
Daniel Granville Bills
Michael dale dorenstein
Michael dale dorenstein
Application Number:
JP5387698A
Publication Date:
December 16, 1998
Filing Date:
March 05, 1998
Export Citation:
Assignee:
Granville-Phillips Company
International Classes:
G01L21/12; (IPC1-7): G01L21/12
Domestic Patent References:
| JP61240135A | ||||
| JP734341U |
Attorney, Agent or Firm:
Seiji Yanagida (1 person outside)