JPS5922504Y2 - Differential pressure response device - Google Patents

Description

[Detailed description of the invention] The invention consists of a measuring diaphragm placed between a pair of opposing backup parts, and a seal that receives one measuring pressure and transmits this pressure to one side of the measuring diaphragm through an internal fluid. It has a diaphragm and a seal diaphragm that receives measurement pressure from the other side and transmits this pressure to the other side of the measurement diaphragm through an internal liquid.The metal film formed on the backup part is used as a fixed electrode, and the measurement electrode is used as a moving electrode. The present invention relates to a differential pressure response device of differential capacitance detection type.

In this type of differential pressure response device, when an excessive differential pressure is applied, the measuring diaphragm is displaced and comes into close contact with the back-up surface, so that no plastic deformation occurs due to the excessive differential pressure.

However, even if the excessive pressure difference is removed, it takes time for the two in close contact to separate due to the viscosity of the internal liquid (silicone oil, etc.), resulting in poor response characteristics.

An object of the present invention is to improve this point and provide a differential pressure response device with good response characteristics.

The present invention will be explained in detail below using the drawings.

FIG. 1 is a sectional view showing an embodiment of the differential pressure responsive device according to the present invention.

In the figure, 1 is a measurement diaphragm and 2 is a body.

The body 2 is divided into two blocks 2A, 2B with respect to the measuring diaphragm 1.

The counterbore holes on the sides of the blocks 2A and 2B facing the measurement diaphragm 1 are filled with an insulating material 21, 22 such as glass that protects the backup part, and its surface has a shape approximately equal to the displacement curved surface of the measurement diaphragm 1. It has a spherical concave surface.

Furthermore, a through hole 23 is provided in the center of each block 2A, 2B.
．． 24 is formed.

3 and 4 are seal diaphragms attached to the surfaces of blocks 2A and 2B opposite to the backup portion, respectively; 5;
, 6 is a metal film (
For example, it is a nickel chromium film with a thickness of about 1 μm).

The surfaces of the metal films 5 and 6 are covered with an insulating film (for example, a silicon oxide film with a thickness of about 1 μm) so that radial grooves are formed on the back-up surface.

FIG. 2 is a view of the back-up surface on the block 2A side viewed from the measurement diaphragm 1 side, and FIG. 3 is a sectional view showing a part of the AA' cross section in FIG. (The explanation will be omitted.)

In FIGS. 2 and 3, 7 is an insulating film that covers the metal film 5. In FIG.

In this embodiment, radial grooves are formed on the back-up surface by exposing the metal film 5 radially.

The metal film 5 and the insulating film 7 are formed by vapor deposition.

The same applies to the metal film 6 and the insulating film covering it.

The blocks 2A, 2B are assembled by pressing the blocks 2A, 2B from both sides against the measurement diaphragm 1 under a certain tension, and welding the 25 portions.

This places the measuring diaphragm 1 in the center of the space 26 formed by the back-up surface with radial grooves.

Further, the compartments 27 and 28 formed by the seal diaphragms 3 and 4, respectively, are connected to the spaces 26 and 26 by the through holes 23 and 24.
will be communicated with.

Note that an incompressible fluid is sealed in the compartments 27 and 28 and the space 26 as an internal liquid.

In the above device, the measuring diaphragm 1 constitutes the moving electrode, and the metal coatings 5 and 6 constitute the fixed electrodes.

Next, the operation will be explained. When measuring pressures are applied to the sealing diaphragms 3, 4, these pressures are applied to both sides of the measuring diaphragm 1 via the internal liquid.

Therefore, the measuring diaphragm 1 is displaced according to the differential pressure, and this displacement is caused by the metal coatings 5, 6 and the measuring diaphragm 1.
It is detected as a capacitance change between

When an excessive differential pressure is applied, the measuring diaphragm 1 comes into close contact with either back-up surface, thereby preventing plastic deformation of the measuring diaphragm 1 and the like.

In such a device, when the excessive differential pressure is released,
The internal liquid passes through the groove relatively quickly to the measuring diaphragm 1.
Since the signal is sent to the entire surface of the area, the response characteristics are good.

Furthermore, since the width of the groove is narrow, the measurement diaphragm 1 will not be plastically deformed.

In addition, in the above explanation, four grooves are formed on the back up surface.
Although the one formed in this manner is shown, the response characteristics can be further improved by increasing the number.

Further, if there is enough space for the electrodes, grooves of the same shape may be formed in the metal coatings 5 and 6. As explained above, according to the present invention, a differential pressure responsive device with good response characteristics can be realized. can do.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the differential pressure responsive device according to the present invention, FIG. 2 is a view showing the back-up surface, and FIG.
It is an AA' cross-sectional view of the figure. 1...Measuring diaphragm, 2...Body, 3゜4...Seal diaphragm, 5, 6...
...Metal film, 7...Insulating film.

Claims (1)

[Scope of utility model registration request] A measuring diaphragm disposed between a pair of opposing backup parts, a first seal diaphragm that receives measuring pressure from one side and transmits this pressure to one side of the measuring diaphragm via an internal liquid, and a second seal diaphragm that receives the pressure and transmits this pressure to the other surface of the measuring diaphragm via an internal liquid, the metal coating formed on the backup part being a fixed electrode, and the measuring diaphragm being a moving electrode. 1. A differential pressure responsive device of dynamic capacitance detection type, characterized in that the surface of the metal film is covered with an insulating film so that radial grooves are formed on the back-up surface.