公开(公告)号：US5421190A

公开(公告)日：1995-06-06

申请号：US70948

申请日：1993-06-04

Applicant: Hubert Brandle ,  Walter Gribi ,  Ken-Yves Haffner

Inventor： Hubert Brandle ,  Walter Gribi ,  Ken-Yves Haffner

IPC: G01N9/00 ,  G01N27/00 ,  H01H33/56 ,  G01H13/00 ,  H01L41/22

CPC classification number: G01N29/036 ,  G01N9/002 ,  H01H33/563 ,  G01N2009/004 ,  G01N2291/0256

Abstract: The device serves to measure the density of a gas, in particular of the insulating gas of a gas-insulated electrical installation. It contains two resonators (11, 12) each comprising a piezoelectric crystal (14, 15) and each comprising two electrodes applied to the crystal. A first (11) of the two resonators (11, 12) is mounted in a first chamber (5) containing the gas to be measured, whereas a second (12) is mounted in a second chamber (6) sealed with respect to the gas.Despite small dimensions and despite simple and robust construction, this device is intended to have a high measurement precision over a long period of time.This is achieved by drawing the two resonators (11, 12) from a multiplicity of similar resonators manufactured by mass production and not subjected to a frequency alignment. The first resonator (11) is unaltered with respect to the manufacture in mass production. The second resonator (12) is likewise unaltered with respect to the manufacture in mass production and, under vacuum and with equality of temperature, it has the same resonance frequency as the first resonator (11) within a specified frequency tolerance. The second resonator (12) may, however, also be modified, by altering its electrodes (18, 19), in such a way that, under vacuum and with equality of temperature, it has the same resonance frequency as the first resonator (11) within the specified frequency tolerance.

Abstract translation: 该装置用于测量气体的密度，特别是气体绝缘电气装置的绝缘气体的密度。 它包含两个谐振器（11,12），每个谐振器包括压电晶体（14,15），每个包括施加到晶体的两个电极。 两个谐振器（11,12）中的第一（11）安装在包含要测量的气体的第一腔室（5）中，而第二腔室（12）安装在相对于第二腔室 加油站。 尽管尺寸小，尽管结构简单而坚固，但该装置的长期测量精度要高。 这是通过从由大量生产制造的多个类似的谐振器中抽出两个谐振器（11,12）而不进行频率对准来实现的。 相对于批量生产的制造，第一谐振器（11）是未改变的。 第二共振器（12）在大规模生产中同样没有变化，并且在真空和温度相等的情况下，它在特定的频率公差范围内具有与第一谐振器（11）相同的共振频率。 然而，第二谐振器（12）可以通过改变其电极（18,19）而被修改，使得在真空和温度相等的情况下，它具有与第一谐振器（11）相同的谐振频率 ）在指定的频率范围内。