JPS601401Y2 - pressure gauge - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a pressure gauge.

More specifically, a diaphragm in contact with the fluid to be measured is used as a moving capacitance electrode, and a fixed capacitance electrode is arranged opposite to this diaphragm, so that displacement of the diaphragm due to fluctuations in the pressure of the fluid to be measured is detected as a change in capacitance. This relates to a pressure gauge.

FIG. 1 shows a conventional example of a pressure gauge that has been commonly used.

In the figure, 1 is a cylindrical pacebook jig having a bottom 11, and 2 is a bellows fixed to the bottom 11 to receive pressure of the fluid to be measured.

A disk-shaped moving capacitor electrode 22 is fixed to the top of the bellows 2 via a zero adjustment spacer 21.

Reference numerals 31 and 32 designate ring-shaped first and second fixed capacitor electrodes which are fixed to the base block and are arranged facing the movable capacitor electrode 22 and spaced apart from each other at equal intervals.

33 is a ring-shaped initial gap spacer sandwiched between the first and second fixed capacitance electrodes 31 and 32.

In the above configuration, when the bellows 2 receives pressure of the measurement fluid, the moving capacitor electrode 22 moves in the left-right direction in the figure, and each of the spaces between the moving capacitor electrode 22 and the first and second fixed capacitor electrodes 31 and 32 is moved. As the gap changes, the respective capacitance C
31 and C32 change.

By differentially processing these capacitances C31 and C3°, an electrical signal corresponding to the measured pressure P can be obtained.

In such devices, it is necessary to adjust the initial gap in order to match the initial capacitance between the two parallel electrodes.
It takes time to assemble.

Furthermore, since the two electrodes are assembled in parallel so as to face each other, the structure becomes complicated and cannot be made at low cost.

The present invention solves this problem.

An object of the present invention is to provide a pressure gauge that has a simple configuration, is easy to assemble, has a large number of parts, and can be manufactured at low cost.

FIG. 2 is an explanatory diagram of the configuration of an embodiment of the present invention.

In the figure, 1 is a body consisting of a cylindrical block 11 and a bottom part 12.

2 is a diaphragm whose cross section is approximately π-shaped;
It covers the recess 13 of the body 1 and forms a chamber 3 with the body 1.

Reference numeral 4 denotes a disc-shaped insulator provided in the chamber 3 opposite to the diaphragm 2, and in this case is made of ceramic.

As shown in FIG. 3, 41 and 42 are first and second fixed capacitance electrodes provided, in this case, vapor-deposited, on the surface of the insulator 4 facing the diaphragm 2.

43 and 44 are leads led out from the eleventh and second fixed capacitance electrodes 41 and 42.

Reference numeral 5 denotes an airtight terminal provided at the opening of a through hole 14 provided in the body 1 and connecting the chamber 3 to the outside.

Reference numeral 6 denotes a seal diaphragm that covers a recess 15 provided at the bottom of the pod 1, and forms a chamber 7 with the recess 15.

16 is a communication hole that communicates the chamber 3 and the chamber 7.

Reference numeral 6 denotes a sealed liquid that fills the chambers 3, 7, and the communication hole 15, and in this case, silicone oil is used.

45 is a spring provided between the bottom part 12 and the insulator 4, which is pushed by the diaphragm 2 at the time of overrange and
This is to prevent the second fixed capacitance electrodes 41 and 42 from being destroyed.

In the above configuration, when the measurement pressure P is applied, the diaphragm 2 is displaced as shown in FIG.
While approaching the fixed capacitance electrode 41, the second fixed capacitance electrode 4
Stay away from 2.

Therefore, the capacitance C41 between the diaphragm 2 and the first fixed capacitance electrode 41 and the capacitance C12 between the diaphragm 2 and the second fixed capacitance electrode 42 exhibit characteristics as shown in FIG.

Thus, if the capacitances C4□ and 04° are processed differentially, the difference between the capacitances C41 and C4° corresponds to the amount of displacement of the diaphragm 2.

Therefore, an electrical signal corresponding to the measured pressure P can be output.

In this case, since the capacitances C4□ and C12 can be arranged on the same plane, the initial capacitances can be easily matched, and assembly is facilitated.

Furthermore, the electrode structure can be simplified and made cheaper.

In addition, since the diaphragm 2 near the surface facing the insulator 4 is provided with a constriction 21, the strain that occurs when the device is assembled is absorbed by the insulator 5 of the diaphragm 2, which functions as a variable capacitance electrode. You can obtain something that is not transmitted to the opposing surface.

Further, since the diaphragm 2 is formed into a π shape, it is possible to reliably manufacture a device in which the fulcrum position of the displacement of the diaphragm 2 is constant, and a device with good characteristics can be obtained.

As described above, according to the present invention, it is possible to realize a pressure gauge with a simple configuration, easy assembly, a small number of parts, and low cost with good characteristics.

[Brief explanation of drawings]

Figure 1 is a conventional example of a pressure gauge that has been commonly used, Figure 2 is an explanatory diagram of the configuration of an embodiment of the present invention, and Figures 3 to 5
The figure is an explanatory diagram of FIG. 2. DESCRIPTION OF SYMBOLS 1... Body 11... Block, 12... Bottom, 13... Recessed part, 2... Diaphragm, 3... Chamber, 4... Insulator, 41... First fixed capacity electrode, 42
...Second fixed capacitance electrode.

Claims (1)

[Scope of utility model registration request] In a pressure gauge comprising a diaphragm in contact with a measuring fluid, a tenon forming a chamber with the diaphragm, and a fixed capacitance electrode provided in parallel opposite to the diaphragm, the diaphragm facing the fixed capacitance electrode is approximately 1. A pressure gauge characterized in that the pressure gauge has a π-shaped cross section, a measurement fluid is introduced into a concave portion formed in the π-shape, and the fixed capacitance electrode is configured in a concentric shape.