CN218994616U

CN218994616U - Pressure-insulation type metal film capacitance vacuum gauge

Info

Publication number: CN218994616U
Application number: CN202222995432.3U
Authority: CN
Inventors: 刘巍; 梁长记; 魏振
Original assignee: Research Institute of Physical and Chemical Engineering of Nuclear Industry
Current assignee: Research Institute of Physical and Chemical Engineering of Nuclear Industry
Priority date: 2022-11-10
Filing date: 2022-11-10
Publication date: 2023-05-09
Anticipated expiration: 2032-11-10

Abstract

The utility model discloses a pressure-proof metal film capacitance vacuum gauge, which comprises a shell, and a metal film and insulating ceramic which are arranged in the shell; an outer capacitor and an inner capacitor are arranged on the insulating ceramic; the capacitance signals of the outer capacitor and the inner capacitor are respectively led out of the shell through the wall penetrating component; the wall penetrating component comprises a conductive spring contacted with the outer capacitor or the inner capacitor, a capacitor leading-out pin with one end contacted with the conductive spring and the other end penetrating through the shell, and a glass composition filled in a gap between the shell and the capacitor leading-out pin. According to the pressure-proof metal film capacitance type vacuum gauge, the through-wall assembly with super-strong sealing performance is selected, and when capacitance signals are reliably led out, the vacuum degree in the reference cavity can be ensured to be kept stable for a long time, so that the obvious zero drift problem of the conventional vacuum gauge is avoided.

Description

Pressure-insulation type metal film capacitance vacuum gauge

Technical Field

The utility model relates to the technical field of design of products, in particular to a pressure-proof metal film capacitance type vacuum gauge.

Background

The vacuum gauge is a key component for measuring the vacuum degree in real time in a vacuum system and is generally divided into a Bolden vacuum gauge, a film capacitance vacuum gauge, a Pirani resistance vacuum gauge, a thermocouple vacuum gauge, a hot cathode ionization vacuum gauge, a cold cathode ionization vacuum gauge and the like, wherein the film capacitance vacuum gauge is the most commonly used instrument for measuring the vacuum degree under the conditions of normal temperature and low vacuum, and has the advantages of wide measuring range, high measuring accuracy and the like. In addition, the vacuum degree comparison principle of the film capacitance vacuum gauge is classified into a differential pressure type vacuum gauge vacuum degree comparison cavity and a pressure insulation type vacuum gauge vacuum degree comparison cavity, namely the differential pressure type vacuum gauge vacuum degree comparison cavity needs to be evacuated by a vacuum pump at any time to maintain the vacuum degree, and the pressure insulation type vacuum gauge vacuum degree comparison cavity is a closed environment without externally connecting a vacuum source.

The prior pressure-proof metal film capacitance vacuum gauge, as shown in figure 1, comprises a shell 1, a film 2 and a ceramic plate 3; the film 2 divides the inner cavity of the shell 1 into a reference cavity A and a medium cavity B; the ceramic plate 3 is positioned in the reference cavity A; the ceramic plate 3 is provided with an inner capacitor 4 and an outer capacitor 5; the inner capacitor 4 and the outer capacitor 5 are respectively connected with the outside through a lead 6 to derive a capacitance signal. In the existing pressure-proof metal film capacitance type vacuum gauge, a common metal wire is used for leading out capacitance signals, and poor contact is easily caused by the change of the installation direction of a product or vibration in the carrying process. When the contact is poor or the position of the wire contact is changed, the capacitance value directly measured is changed, so that the zero drift problem is caused, and the objectivity of the measurement result of the vacuum system is lost. If long-term use is required, an operator must frequently perform a zero-setting operation on the vacuum gauge, so that the vacuum gauge cannot continuously work.

Disclosure of Invention

The utility model aims to provide a pressure-proof metal film capacitance type vacuum gauge aiming at the technical defect that the prior pressure-proof metal film capacitance type vacuum gauge is easy to have zero drift.

The technical scheme adopted for realizing the purpose of the utility model is as follows:

a pressure-proof metal film capacitance vacuum gauge comprises a shell, and a metal film and insulating ceramics which are arranged in the shell; the metal film divides the inner cavity of the shell into a vacuum reference cavity and a working medium cavity; the insulating ceramic is fixedly arranged in the vacuum reference cavity; an outer capacitor and an inner capacitor are arranged on the insulating ceramic; the capacitance signals of the outer capacitor and the inner capacitor are respectively led out of the shell through the wall penetrating component; the wall penetrating component comprises a conductive spring in contact with the outer capacitor or the inner capacitor and a capacitor leading-out needle, one end of the capacitor leading-out needle is in contact with the conductive spring, and the other end of the capacitor leading-out needle passes through the shell in a sealing way; the gap between the shell and the capacitor lead-out needle is filled with a glass composition, and the capacitor lead-out needle is made of copper or silver.

In the above scheme, the shell comprises a top cover, an upper shell and a lower shell; the metal film is sandwiched between the upper case and the lower case.

In the above aspect, a mounting boss for mounting the insulating ceramic is formed on an inner wall of the upper case; the inner wall of the top cover extends downwards to form a compression ring used for compressing the insulating ceramic on the carrying boss.

In the above scheme, the outer capacitor comprises an upper outer capacitor plate and a lower outer capacitor plate which are arranged on the upper side and the lower side of the insulating ceramic; the inner capacitor comprises an upper inner capacitor plate and a lower inner capacitor plate which are arranged on the upper side and the lower side of the insulating ceramic; the upper outer capacitance pole plate and the lower outer capacitance pole plate as well as the upper inner capacitance pole plate and the lower inner capacitance pole plate are connected in a conductive way through a group of conductive nuts and conductive bolts which are matched with each other.

In the above scheme, the upper outer capacitor plate, the upper inner capacitor plate, the lower outer capacitor plate and the lower inner capacitor plate are made of gold, silver or palladium.

In the above scheme, the upper outer capacitor plate, the upper inner capacitor plate, the lower outer capacitor plate and the lower inner capacitor plate are processed by spraying, electroplating or magnetron sputtering.

In the above scheme, the top cover is provided with a grounding end; the top cover, the upper shell and the metal film are made of stainless steel, monel or Inkel.

In the scheme, the top cover is provided with the getter storage cavity; the getter is stored in the getter storage cavity; the getter is fixed in the getter storage chamber by a barrier net.

In the above scheme, the top cover is provided with an evacuation port.

In the above scheme, the bottom of the lower shell is provided with a sealing external thread for connecting a vacuum system.

In the above scheme, a filter screen is arranged in the lower shell.

Compared with the prior art, the utility model has the beneficial effects that:

1. according to the pressure-proof metal film capacitance type vacuum gauge provided by the utility model, the through-wall component with super-strong sealing performance is selected, so that the capacitance signal is reliably led out, and meanwhile, the long-term stability of the vacuum degree in the reference cavity can be ensured, thereby avoiding the obvious zero drift problem of the conventional vacuum gauge.

2. According to the pressure-proof metal film capacitance type vacuum gauge provided by the utility model, the capacitance material with higher conductivity, the conductive spring and the conductive bolt and nut are selected, so that the problem of deviation of capacitance value reading in the existing vacuum gauge can be effectively solved, and the measurement accuracy of a product is improved.

3. The pressure-proof metal film capacitance vacuum gauge provided by the utility model has the advantages of compact structure and high integration level of each part, small product volume and light weight, and can effectively avoid the problems of measuring failure and the like when the product is carried and subjected to vibration.

Drawings

FIG. 1 is a schematic diagram of a conventional pressure-proof metal film capacitance type vacuum gauge;

fig. 2 is a schematic structural view of a pressure-proof metal film capacitance type vacuum gauge.

In the figure: 1-shell, 2-film, 3-ceramic plate, 4-inner capacitor, 5-outer capacitor, 6-wire, 7-metal film, 8-insulating ceramic, 9-top cap, 10-upper shell, 11-lower shell, 12-clamp ring, 13-upper outer capacitor plate, 14-upper inner capacitor plate, 15-lower outer capacitor plate, 16-lower inner capacitor plate, 17-conductive nut, 18-conductive bolt, 19-conductive spring, 20-capacitor pin, 21-glass composition, 22-ground, 24-getter, 25-evacuation port, 26-sealed external screw thread, 27-filter screen, 28-barrier net.

Detailed Description

The present utility model will be described in further detail with reference to specific examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Example 1

A pressure-proof metal film capacitance vacuum gauge, as shown in figure 2, comprises a shell, a metal film 7 and insulating ceramics 8, wherein the metal film 7 and the insulating ceramics 8 are arranged inside the shell;

the metal film 7 divides the inner cavity of the shell into a vacuum reference cavity and a working medium cavity; the insulating ceramic 8 is fixedly arranged in the vacuum reference cavity;

an outer capacitor and an inner capacitor are arranged on the insulating ceramic 8; the capacitance signals of the outer capacitor and the inner capacitor are respectively led out of the shell through the wall penetrating component;

the wall penetrating component comprises a conductive spring 19 in contact with the outer capacitor or the inner capacitor, and a capacitor leading-out pin 20, one end of the capacitor leading-out pin is in contact with the conductive spring 19, and the other end of the capacitor leading-out pin penetrates through the shell. The gap between the casing and the capacitance lead-out pin 20 is filled with a glass composition 21. The leak rate Q of the vacuum seal formed by the capacitance lead-out pin 20, the glass composition 21 and the top cover 9 is less than or equal to 1 multiplied by 10 ^-11 Pa·m ³ /s。

According to the pressure-proof metal film capacitance type vacuum gauge, the through-wall assembly with super-strong sealing performance is selected, and when capacitance signals are reliably led out, the vacuum degree in the reference cavity can be ensured to be kept stable for a long time, so that the obvious zero drift problem of the conventional vacuum gauge is avoided.

Example 2

This embodiment describes detailed structural information based on embodiment 1.

As shown in fig. 2, the housing includes a top cover 9, an upper housing 10, and a lower housing 11; the metal film 7 is clamped between the upper shell 10 and the lower shell 11, and divides the inner cavity of the shell into a vacuum reference cavity and a working medium cavity. Specifically, a sealed area formed by enclosing the top cover 9, the upper shell 10 and the metal film 7 is a vacuum reference cavity; the open area formed by the lower shell 11 and the metal film 7 is the working medium cavity.

Specifically, a mounting boss for mounting the insulating ceramic 8 is formed on the inner wall of the upper case 10; the inner wall of the top cover 9 extends downwards to form a compression ring 12 for compressing the insulating ceramic 8 on the carrying boss.

The top cover 9 is provided with a getter storage cavity; the getter 24 is stored in the getter storage cavity, and can be activated at a high temperature (for example, 200 ℃) to continuously adsorb the gas in the vacuum reference cavity, so that the vacuum degree of the vacuum reference cavity is ensured. The getter 24 is secured within the getter housing chamber by a barrier web 28. The metallic material of the barrier net 28 may be stainless steel, monel, inconel, or the like.

The bottom of the lower housing 11 is provided with a sealing external thread 26 for connection to a vacuum system.

A filter screen 27 is arranged in the lower shell 11 and is used for blocking impurity particles in the vacuum system so as to prevent the metal film 7 from being impacted or pollute the inside of the working medium cavity.

The top cover 9 is provided with an evacuation port 25 which is an internal evacuation channel before welding and forming the vacuum reference cavity.

The pressure-proof metal film capacitance vacuum gauge has the advantages of compact structure and high integration level of parts, small volume and light weight of products, and can effectively avoid the problems of measuring failure and the like when the products are carried and subjected to vibration.

Example 3

This embodiment is based on

embodiments

1 and 2, and material information thereof is described.

The insulating ceramic 8 is high-density alumina ceramic.

The insulating ceramic 8 is provided with an outer capacitor and an inner capacitor. Specifically, the outer capacitor includes upper and lower

outer capacitor plates

13 and 15 disposed on upper and lower sides of the insulating ceramic 8; the inner capacitor includes an upper inner capacitor plate 14 and a lower inner capacitor plate 16 disposed on both upper and lower sides of the insulating ceramic 8. The upper outer capacitor plate 13 and the lower outer capacitor plate 15, and the upper inner capacitor plate 14 and the lower inner capacitor plate 16 are electrically connected through a group of mutually matched conductive nuts 17 and conductive bolts 18.

The upper outer capacitor plate 13, the upper inner capacitor plate 14, the lower outer capacitor plate 15 and the lower inner capacitor plate 16 are made of metals with higher conductivity, such as gold, silver, palladium and the like, and are obtained by adopting a spraying, electroplating or magnetron sputtering mode.

The top cover 9 is provided with a grounding end 22. Since the top cover 9, the upper case 10 and the metal film 7 are made of the same metal material, they are connected and fixed by welding. Thus, the grounding terminal 22 is a pin of the metal film 7 as a capacitor plate. As the metal materials of the top cover 9, the upper case 10 and the metal film 7, stainless steel, monel, inconel, etc. may be used.

According to the pressure-insulation type metal film capacitance type vacuum gauge, the capacitance material with high conductivity, the conductive spring 19, the conductive nut 17 and the conductive bolt 18 are selected, so that the problem of deviation of capacitance value reading in the existing vacuum gauge can be effectively solved, and the measurement accuracy of a product is improved.

The foregoing is merely a preferred embodiment of the present utility model and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present utility model, which are intended to be comprehended within the scope of the present utility model.

Claims

1. A pressure-proof metal film capacitance vacuum gauge is characterized in that: comprises a shell, a metal film and insulating ceramics, wherein the metal film and the insulating ceramics are arranged inside the shell;

the metal film divides the inner cavity of the shell into a vacuum reference cavity and a working medium cavity; the insulating ceramic is fixedly arranged in the vacuum reference cavity;

an outer capacitor and an inner capacitor are arranged on the insulating ceramic; the capacitance signals of the outer capacitor and the inner capacitor are respectively led out of the shell through the wall penetrating component;

the wall penetrating component comprises a conductive spring in contact with the outer capacitor or the inner capacitor and a capacitor leading-out needle, one end of the capacitor leading-out needle is in contact with the conductive spring, and the other end of the capacitor leading-out needle passes through the shell in a sealing way; a gap between the shell and the capacitance lead-out needle is filled with a glass composition; the capacitance leading-out needle is made of copper or silver.

2. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 1, wherein: the shell comprises a top cover, an upper shell and a lower shell;

the metal film is sandwiched between the upper case and the lower case.

3. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: a carrying boss for carrying the insulating ceramic is formed on the inner wall of the upper shell; the inner wall of the top cover extends downwards to form a compression ring used for compressing the insulating ceramic on the carrying boss.

4. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 1, wherein: the outer capacitor comprises an upper outer capacitor plate and a lower outer capacitor plate which are arranged on the upper side and the lower side of the insulating ceramic;

the inner capacitor comprises an upper inner capacitor plate and a lower inner capacitor plate which are arranged on the upper side and the lower side of the insulating ceramic;

the upper outer capacitance pole plate and the lower outer capacitance pole plate as well as the upper inner capacitance pole plate and the lower inner capacitance pole plate are connected in a conductive way through a group of conductive nuts and conductive bolts which are matched with each other.

5. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 4, wherein: the upper outer capacitor plate, the upper inner capacitor plate, the lower outer capacitor plate and the lower inner capacitor plate are made of gold, silver or palladium.

6. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 4, wherein: the upper outer capacitor plate, the upper inner capacitor plate, the lower outer capacitor plate and the lower inner capacitor plate are processed in a spraying, electroplating or magnetron sputtering mode.

7. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: the top cover is provided with a grounding end;

the top cover, the upper shell and the metal film are made of stainless steel, monel or Inkel.

8. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: the top cover is provided with a getter storage cavity; the getter is stored in the getter storage cavity; the getter is fixed in the getter storage chamber by a barrier net.

9. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: the top cover is provided with an evacuation port.

10. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: the bottom of the lower shell is provided with a sealing external thread for connecting a vacuum system.

11. The pressure-proof metal thin film capacitance type vacuum gauge according to claim 2, wherein: a filter screen is arranged in the lower shell.