Diaphragm for a capacitive vacuum gauge and capacitive vacuum gauge comprising such a diaphragm

Abstract

The application provides a diaphragm of a capacitive vacuum gauge and the capacitive vacuum gauge, comprising a diaphragm layer, an etching-resistant layer and a conductive layer, the diaphragm layer is used for dividing the internal space of the vacuum gauge into a vacuum space and a measured space, the material of the diaphragm layer is quartz material; the etching-resistant layer is arranged at the end of the diaphragm layer away from a fixed electrode; and the conductive layer is arranged at the end of the diaphragm layer close to the fixed electrode and used for electrically connecting with an electrode column of the vacuum gauge. The diaphragm layer made of quartz material is used as a diaphragm, and the etching-resistant layer is arranged at the end of the diaphragm layer in the measured space, so that the etching resistance or corrosion resistance of the vacuum gauge is effectively improved, the stress times of the diaphragm are increased, the vacuum gauge has the characteristics of high precision, etching resistance, long service life, reusability, good stability and wide actual application, and the cost of the vacuum gauge is effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vacuum gauges, in particular to a diaphragm of a capacitive vacuum gauge and a capacitive vacuum gauge. BACKGROUND

[0002] The vacuum gauge can be used for detecting the pressure of gas or liquid. In actual use, it may involve sulfuric acid, nitric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, perchloric acid, sodium hydroxide, sulfur dioxide, sulfur trioxide, nitrogen dioxide and other substances with etching properties. They can cause the measurement diaphragm of the vacuum gauge to be corroded, thereby reducing the sensitivity of the vacuum gauge and causing the vacuum gauge to fail. Therefore, it is very important for the vacuum gauge to have etching resistance. The current thin film of the vacuum gauge tube mainly uses metal sheets, but the stress of the metal sheets is relatively low, which is easy to cause mechanical fatigue and easy to be corroded.

[0003] In the prior art, in the patent (CN 107843385 A), the diatomic aluminum oxide film is used as the thin film of the vacuum gauge tube, which can greatly improve the stress times of the thin film. The surface of the diatomic aluminum oxide film is plated with gold, which can effectively ensure that the thin film has no air leakage and no air release. The material of the shell is hastelloy or nickel-copper alloy, which has good corrosion resistance and can be applied in harsh corrosive environments. However, since the Young's modulus of diatomic aluminum oxide is 370 GPa, which is larger than the Young's modulus of commonly used metal films, in actual application, the film strain is small and the test precision is low. In fact, the precision is sacrificed for etching resistance. Moreover, plating gold on the diatomic aluminum oxide film can only improve the etching resistance to a certain extent, but since gold can be etched by HF (hydrofluoric acid), the actual application is limited.

[0004] In the patent (CN 107976279 A), a pre-chamber is provided in advance, a pre-diaphragm is arranged in the pre-chamber, a pressure transmission cavity is formed between the pre-diaphragm and the measurement diaphragm, and the pressure transmission cavity is filled with pressure transmission liquid. Even if the pre-diaphragm is damaged by corrosive gas or high-temperature gas, the pre-diaphragm in the pre-chamber can be easily replaced, which will not affect the vacuum gauge diaphragm. However, the method of sacrificing the pre-diaphragm to protect the vacuum gauge diaphragm increases the complexity of the process and increases the cost.

[0005] In the patent (CN 107845459 A), a thin film piece made of sapphire material is used as a variable electrode, which has the advantages of high stress times and corrosion resistance. However, the use of sapphire material to make the thin film piece increases the cost. SUMMARY

[0006] The application provides a diaphragm of a capacitive vacuum gauge and the capacitive vacuum gauge, which solve the problems of small strain, poor etching resistance or high cost of the diaphragm of the capacitive vacuum gauge in the prior art.

[0007] The application provides a diaphragm of a capacitive vacuum gauge, which comprises:

[0008] A diaphragm layer is used for dividing the internal space of the vacuum gauge into a vacuum space and a measured space, and the material of the diaphragm layer is quartz.

[0009] An etching-resistant layer is arranged at one end of the diaphragm layer away from the fixed electrode.

[0010] A conductive layer is arranged at one end of the diaphragm layer close to the fixed electrode and is used for electrically connecting with the electrode column of the vacuum gauge.

[0011] According to the diaphragm of the capacitive vacuum gauge, the mass of the etching-resistant layer is less than 5% of the mass of the conductive layer, and the thickness of the etching-resistant layer is less than the thickness of the diaphragm layer.

[0012] According to the diaphragm of the capacitive vacuum gauge, the cross-sectional shape and size of the diaphragm layer, the etching-resistant layer and the conductive layer are consistent.

[0013] According to the diaphragm of the capacitive vacuum gauge, the material of the etching-resistant layer is one or more of Y2O3, Al2O3, YF2, Er2O3, Gd2O, RuO2, Tr2O3, Zr2O3, AlN, SiC, Si2N3, furan powder, metal, alloy and stainless steel.

[0014] According to the diaphragm of the capacitive vacuum gauge, the material of the conductive layer is metal or conductive paste.

[0015] According to the diaphragm of the capacitive vacuum gauge, the etching-resistant layer is sputtered, hot-melted, sintered or welded on the diaphragm layer.

[0016] According to the diaphragm of the capacitive vacuum gauge, the conductive layer is sputtered, hot-melted, sintered or welded on the diaphragm layer.

[0017] According to the diaphragm of the capacitive vacuum gauge, the surface roughness of the diaphragm layer is less than or equal to 10 mu m.

[0018] According to the diaphragm of a capacitive vacuum gauge provided by the present invention, the bow height of the diaphragm layer is less than or equal to 10 mm.

[0019] The present invention further provides a capacitive vacuum gauge, comprising a diaphragm, wherein the diaphragm is the diaphragm of the capacitive vacuum gauge as described in any one of the above.

[0020] The diaphragm of the capacitive vacuum gauge and the capacitive vacuum gauge provided by the present invention use a diaphragm layer made of quartz material as a diaphragm, and an anti-etching layer is provided at one end of the diaphragm layer located in the measured space, thereby effectively improving the etching resistance or corrosion resistance of the vacuum gauge and increasing the stress times of the diaphragm, so that the vacuum gauge has the characteristics of high precision, etching resistance, long life, reusability, good stability and wide practical application, and effectively reducing the cost of the vacuum gauge. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a structural schematic diagram of the diaphragm of the capacitive vacuum gauge provided by the present invention.

[0023] Reference numerals:

[0024] 1: Diaphragm layer; 2: Anti-etching layer; 3: Conductive layer. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0026] The following combination Figure 1 The diaphragm of the capacitance vacuum gauge and the capacitance vacuum gauge thereof according to the present invention are described.

[0027] like Figure 1 As shown, the present invention provides a diaphragm of a capacitive vacuum gauge, comprising a diaphragm layer 1, an anti-etching layer 2 and a conductive layer 3.

[0028] Among them, the diaphragm layer 1 is used to separate the internal space of the vacuum gauge into a vacuum space and a measured space, and the material of the diaphragm layer 1 can be quartz material. The diaphragm layer 1 made of quartz material is flat and the test results are accurate. During the test process, the test results are highly accurate. After the diaphragm layer 1 is deformed for a long time, after recovery, the diaphragm layer 1 can still ensure its own flatness and is not easy to deform. The vacuum gauge prepared with quartz diaphragm as the diaphragm has high precision and good stability, and the quartz material is acid and alkali resistant, thereby improving the etching resistance of the diaphragm and reducing the cost of the diaphragm.

[0029] The conductive layer 3 is arranged at one end of the diaphragm layer 1 close to the fixed electrode and is used to electrically connect to the electrode column of the vacuum gauge so that the conductive layer 3 and the fixed electrode together form a capacitor; the anti-etching layer 2 is arranged at one end of the diaphragm layer 1 away from the fixed electrode, that is, the anti-etching layer 2 is located in the measured space to prevent the diaphragm layer 1 from being corroded or etched by the measured air or liquid, thereby improving the etching resistance of the diaphragm.

[0030] Here, the fixed electrode is a fixed electrode of a capacitive vacuum gauge.

[0031] In this arrangement, a diaphragm layer 1 made of quartz material is used as a diaphragm, and an anti-etching layer 2 is provided at one end of the diaphragm layer 1 located in the measured space, which effectively improves the etching resistance or corrosion resistance of the vacuum gauge and increases the stress times of the diaphragm, thereby making the vacuum gauge have the characteristics of high precision, etching resistance, long life, reusability, good stability and wide practical application, and effectively reducing the cost of the vacuum gauge.

[0032] In an optional embodiment of the present invention, the mass of the anti-etching layer 2 may be 5% smaller than the mass of the conductive layer 3 to reduce the stress of the diaphragm.

[0033] Furthermore, the thickness of the anti-etching layer 2 is smaller than the thickness of the membrane layer 1, thus further reducing the stress of the membrane.

[0034] In an optional embodiment of the present invention, the cross-sectional shapes and sizes of the diaphragm layer 1, the anti-etching layer 2 and the conductive layer 3 are consistent, that is, the anti-etching layer 2 and the conductive layer 3 are respectively covered on both sides of the diaphragm layer 1. This is beneficial to improving the etching resistance of the diaphragm and can ensure that the film has no leakage and no degassing.

[0035] Specifically, the process of the diaphragm is to laminate a thin film with anti-etching properties (anti-etching layer 2) on the lower surface of the quartz diaphragm layer 1, and laminate a conductive layer 3 on the upper surface.

[0036] In an optional embodiment, the material of the etching-resistant layer 2 can be one or more of Y2O3 (yttrium trioxide), Al2O3 (aluminum trioxide), YF2, Er2O3 (erbium oxide), Gd2O, RuO2 (ruthenium dioxide), Tr2O3, Zr2O3, AlN, SiC, Si2N3, furan powder, metal, alloy, and stainless steel. In this way, by combining the etching-resistant layer 2 of different materials on the diaphragm layer 1, the required etching resistance can be achieved. Here, the material of the etching-resistant layer 2 can be a metal such as Ni (nickel), Cr (chromium), Mn (manganese), Mo (molybdenum), Ti (titanium), Au (gold), Ag (silver), Cu (copper), etc., and the material of the etching-resistant layer 2 can also be a ferrochrome alloy, a nickel-based alloy, etc.

[0037] The material of the conductive layer 3 can be a metal or a conductive paste, so as to be electrically connected with the electrode column of the vacuum gauge, thereby forming a capacitor together with the fixed electrode.

[0038] Here, the conductive paste is also called conductive glue, which is a mixture of noble metal powder, base metal powder, glass powder, and synthetic resin. The conductive paste is a material in which conductive powder is uniformly added to an adhesive, and after curing, a conductive body is formed. It is used in the formation of electronic circuits, the formation of electrodes of electronic components, the leading-out of lead terminals, the formation of circuit junctions, etc.

[0039] In an optional embodiment of the present application, the etching-resistant layer 2 can be provided on the diaphragm layer 1 by sputtering or hot melting or sintering or welding, and the conductive layer 3 can be provided on the diaphragm layer 1 by sputtering or hot melting or sintering or welding, so as to realize the combination of the etching-resistant layer 2 and the conductive layer 3 with the diaphragm layer 1.

[0040] In one embodiment, the etching-resistant layer 2 can be a metal Ni layer, the thickness of the metal Ni layer can be 1000A (angstrom), the material of the conductive layer 3 can be metal Ni, and the thickness of the conductive layer 3 can be 100A, the thickness of the diaphragm layer 1 can be 100 microns, and the diameter can be 20 millimeters. That is, a metal Ni layer with a thickness of 1000A is sputtered on the lower surface (the surface away from the fixed electrode) of the diaphragm layer 1 of quartz material with a thickness of 100 microns and a diameter of 20 millimeters; a metal Ni layer with a thickness of 100A is sputtered on the upper surface (the surface close to the fixed electrode) of the diaphragm layer 1, thereby forming a diaphragm of a capacitive vacuum gauge.

[0041] In another embodiment, the etching-resistant layer 2 can be an aluminum oxide layer, the thickness of the aluminum oxide layer can be 100 angstroms (A), the material of the conductive layer 3 can be metal Ni, and the thickness of the conductive layer 3 can be 100 angstroms, and the diaphragm layer 1 can have a thickness of 100 microns and a diameter of 20 millimeters. That is, an aluminum oxide layer with a thickness of 100 angstroms is screen-printed on the lower surface (the surface away from the fixed electrode) of the diaphragm layer 1 made of quartz with a thickness of 100 microns and a diameter of 20 millimeters, and then sintered; a layer of metal Ni with a thickness of 100 angstroms is sputtered on the upper surface (the surface close to the fixed electrode) of the diaphragm layer 1, thereby forming the diaphragm of the capacitive vacuum gauge.

[0042] In this embodiment, the surface roughness of the diaphragm layer 1 is less than or equal to 10 microns, so as to reduce the stress of the diaphragm and improve the measurement accuracy.

[0043] In this embodiment, the arch height of the diaphragm layer is less than or equal to 10 millimeters, so that the arch height of the diaphragm of the capacitive vacuum gauge is less than or equal to 10 millimeters, that is, the deformation of the diaphragm of the capacitive vacuum gauge is less than or equal to 10 millimeters.

[0044] The capacitive vacuum gauge provided by the present application will be described below, and the diaphragm of the capacitive vacuum gauge described below can be referred to in correspondence with the diaphragm of the capacitive vacuum gauge described above.

[0045] The present application provides a capacitive vacuum gauge, which comprises a diaphragm, the diaphragm can be the diaphragm of the capacitive vacuum gauge described in any of the above embodiments, and the capacitive vacuum gauge achieves the same beneficial effects as the diaphragm of the capacitive vacuum gauge provided by the present application. The etching resistance or corrosion resistance of the vacuum gauge is effectively improved, and the stress frequency of the diaphragm is improved, so that the vacuum gauge has the characteristics of high precision, etching resistance, long service life, reusability, good stability and wide practical application, and the cost of the vacuum gauge is effectively reduced.

[0046] The device embodiments described above are only illustrative, and part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to actual needs. Those skilled in the art can understand and implement without creative labor.

[0047] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A diaphragm for a capacitive vacuum gauge, characterized in that The application relates to a diaphragm for a capacitive vacuum gauge, comprising: a diaphragm layer for separating the internal space of the vacuum gauge into a vacuum space and a measured space, wherein the diaphragm layer is made of quartz; an etching-resistant layer arranged at one end of the diaphragm layer away from a fixed electrode; and a conductive layer arranged at the other end of the diaphragm layer close to the fixed electrode, and used for electrically connecting with an electrode column of the vacuum gauge. The mass of the etching-resistant layer is 5% less than that of the conductive layer, and the thickness of the etching-resistant layer is less than that of the diaphragm layer. The cross-sectional shape and size of the diaphragm layer, the etching-resistant layer and the conductive layer are consistent. The surface roughness of the diaphragm layer is less than or equal to 10 mu m, and the arch height of the diaphragm layer is less than or equal to 10 mm. The etching-resistant layer is made of one or more of Y2O3, Al2O3, YF2, Er2O3, Gd2O, RuO2, Tr2O3, Zr2O3, AlN, SiC, Si2N3, furan powder, Ni, Cr, Mn, Mo, Ti, Au, Ag, Cu, stainless steel and nickel-based alloy. The etching-resistant layer is made of one or more of Y2O3, Al2O3, YF2, Er2O3, Gd2O, RuO2, Tr2O3, Zr2O3, AlN, SiC, Si2N3, furan powder, Ni, Cr, Mn, Mo, Ti, Au, Ag, Cu, stainless steel and nickel-based alloy. The conductive layer is made of metal or conductive paste.

2. The diaphragm of a capacitive vacuum gauge according to claim 1, characterized in that The etching-resistant layer is sputtered, hot-melted, sintered or welded on the diaphragm layer.

3. The diaphragm of a capacitive vacuum gauge according to claim 1, characterized in that The conductive layer is sputtered, hot-melted, sintered or welded on the diaphragm layer.

4. The diaphragm of a capacitive vacuum gauge according to claim 1, characterized in that The application further relates to a capacitive vacuum gauge comprising a diaphragm as described in any one of claims 1-6.

5. The diaphragm of a capacitive vacuum gauge according to claim 1, characterized in that ​ 6. The diaphragm of a capacitive vacuum gauge according to claim 1, characterized in that ​ 7. A capacitive vacuum gauge characterized by ​

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