A uniform deformation capacitive pressure sensor diaphragm

Abstract

The utility model relates to a kind of uniform deformation capacitor pressure sensor diaphragm, including membrane body, membrane body one side is etching surface, the other side is flat surface;Several radial etching grooves are uniformly etched with center radiation on etching surface, several circumferential etching grooves are uniformly etched with center annular on etching surface;Radial etching groove and circumferential etching groove divide etching surface from inside to outside into middle reinforcing area, deformation buffer area, deformation dispersion area;Middle reinforcing area is composed of several annularly surrounded triangular bosses, and deformation buffer area has several buffer quadrilateral bosses, and the buffer quadrilateral boss includes buffer top side, buffer side, buffer bottom side.The utility model makes diaphragm deformation more uniform by laser etching, avoids local deformation to cause diaphragm structure fatigue, creep and due to microscopic defect.

Description

Technical Field

[0001] This utility model belongs to the field of capacitive pressure sensor technology, and relates to a uniformly deformable capacitive pressure sensor diaphragm. Background Technology

[0002] Differential capacitive pressure sensors operating in harsh environments such as nuclear power plants and aerospace typically use metal diaphragms as the core pressure-sensing element. Existing diaphragms mostly employ a ring-shaped concentric corrugated structure, which, while offering advantages in enhancing elastic response, still suffers from the following problems:

[0003] 1. Stress concentration, especially in the central region;

[0004] 2. It is highly sensitive to microscopic defects (such as vacancies and microcracks), and its mechanical properties deteriorate significantly.

[0005] 3. Under long-term irradiation and high-temperature service, creep and fatigue are prone to occur, affecting stability. Summary of the Invention

[0006] The purpose of this invention is to provide a uniformly deformable capacitive pressure sensor diaphragm that can solve the above-mentioned problems.

[0007] According to the technical solution provided by this utility model: a uniformly deformable capacitive pressure sensor diaphragm includes a diaphragm body, one side of which is an etched surface and the other side is a flat surface; several radial etched grooves are evenly etched radially around the center on the etched surface, and several circumferential etched grooves are evenly etched in a ring around the center on the etched surface; the radial and circumferential etched grooves divide the etched surface from the inside to the outside into an intermediate reinforcement zone, a deformation buffer zone, and a deformation dispersion zone; the intermediate reinforcement zone is composed of several triangular protrusions surrounding it in a ring, and the deformation buffer zone is composed of several buffer quadrilateral protrusions, each buffer quadrilateral protrusion including a buffer top edge, a buffer side edge, and a buffer bottom edge; the buffer side edges are symmetrically arranged and contract towards the center of the diaphragm body; the buffer top edge connects to the inner ends of the two buffer side edges, and the buffer bottom edge connects to the outer ends of the two buffer side edges; the buffer top edge is a straight line, and the buffer bottom edge is an arc; the outer periphery of the deformation dispersion zone is a welded ring surface.

[0008] As a further improvement of this utility model, the membrane is a circular metal substrate.

[0009] As a further improvement of this utility model, the triangular boss is an isosceles triangle with its vertex pointing towards the center of the membrane.

[0010] As a further improvement of this utility model, the deformation dispersion zone is composed of several concentric circumferential reinforcing rings. Each circumferential reinforcing ring is composed of several annular deformation dispersion quadrilateral protrusions. The annular deformation dispersion quadrilateral protrusions include a deformation dispersion top edge, a deformation dispersion side edge, and a deformation dispersion bottom edge. The deformation dispersion side edges are symmetrically arranged and contract towards the center of the membrane. The deformation dispersion top edge connects to the inner ends of the two deformation dispersion side edges, and the deformation dispersion bottom edge connects to the outer ends of the two deformation dispersion side edges. The deformation dispersion top edge and the deformation dispersion bottom edge are arcs.

[0011] As a further improvement of this utility model, the surface roughness Ra of the welded annular surface is ≤0.8μm.

[0012] As a further improvement of this utility model, the number of radial etching grooves is 18.

[0013] As a further improvement of this utility model, the intermediate reinforcement region occupies approximately 10% of the area of ​​the etched surface.

[0014] As a further improvement of this utility model, the depth of the radial etching groove and the circumferential etching groove is no more than half the thickness of the film.

[0015] The positive and progressive effects of this application are as follows:

[0016] 1. This utility model significantly reduces stress concentration and improves the stability of the diaphragm structure;

[0017] 2. This utility model still has good mechanical robustness even in the presence of local defects (such as vacancies or holes);

[0018] 3. This invention significantly improves the sensor's response sensitivity, linearity, and fatigue life;

[0019] 4. The processing technology of this utility model is mature, and the structure has good manufacturability and industrialization prospects. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the present invention.

[0021] Figure 2 This is a schematic diagram of the triangular boss 3 and the buffer quadrilateral boss 4 of this utility model. Detailed Implementation

[0022] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this utility model described herein. Furthermore, terms such as "comprising" and "having" mean that in addition to those already listed in "comprising" and "having," other unlisted contents may also be included; for example, a process, method, system, product, or device may include a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0025] Due to the angle of the drawing, some parts may not be drawn, but their positions and connections can be understood from the text descriptions.

[0026] like Figure 1 As shown, this utility model is a diaphragm for a nuclear-grade differential capacitive pressure sensor, comprising a diaphragm body, one side of which is an etched surface and the other side is a flat surface. Several radial etched grooves 1 are evenly distributed radially from the center on the etched surface, and several circumferential etched grooves 2 are evenly distributed annularly from the center on the etched surface.

[0027] The membrane is a circular metal substrate with a diameter of 13.7 mm, preferably made of high-temperature and radiation-resistant alloy materials such as Inconel 718 alloy and 316L stainless steel.

[0028] The radial etching groove 1 and the circumferential etching groove 2 divide the etched surface into an intermediate reinforcement zone, a deformation buffer zone, and a deformation dispersion zone from the inside to the outside.

[0029] like Figure 2 As shown, the intermediate reinforcement region is composed of several triangular protrusions 3 arranged in a ring. Each triangular protrusion 3 is an isosceles triangle with its apex pointing towards the center of the membrane. Due to the stability of the triangle, the deformation of the membrane center is reduced when the membrane is under stress, and microcracks caused by stress concentration are also reduced.

[0030] The deformation buffer zone consists of several quadrilateral protrusions 4, which resemble isosceles trapezoids. Each protrusion 4 includes a top edge 4-1, side edges 4-2, and a bottom edge 4-3. The side edges 4-2 are symmetrically arranged and taper towards the center of the membrane. The top edge 4-1 connects to the inner ends of the two side edges 4-2, and the bottom edge 4-3 connects to the outer ends of the two side edges 4-2. The top edge 4-1 is a straight line, corresponding to the bottom edge of the triangular protrusion 3. The bottom edge 4-3 is arc-shaped. This symmetrically tapering side design gradually disperses stress from the central area to the periphery, reducing the impact of local defects on the overall mechanical properties.

[0031] The deformation dispersion zone consists of several concentric circumferential reinforcing rings. Each circumferential reinforcing ring comprises several annular deformation dispersion quadrilateral protrusions 5, which are similar to isosceles trapezoids. Each annular deformation dispersion quadrilateral protrusion 5 includes a top deformation dispersion edge 5-1, side deformation dispersion edges 5-2, and a bottom deformation dispersion edge 5-3. The side deformation dispersion edges 5-2 are symmetrically arranged and contract towards the center of the membrane. The top deformation dispersion edge 5-1 connects to the inner ends of the two side deformation dispersion edges 5-2, and the bottom deformation dispersion edge 5-3 connects to the outer ends of the two side deformation dispersion edges 5-2. The top deformation dispersion edge 5-1 is an arc, corresponding to the bottom deformation dispersion edge 4-3. The bottom deformation dispersion edge 5-3 is also an arc. This further uniformly disperses stress to the welding ring surface 6, avoiding defect sensitivity issues caused by abrupt changes in edge rigidity.

[0032] The outer periphery of the deformation dispersion zone is a welding ring surface 6 with a surface roughness Ra≤0.8μm, which is a vacuum electron beam welding zone to ensure the sealing of the diaphragm installed in the sensor.

[0033] The deformation dispersion zone is located near the welding ring surface 6, where its rigidity is strongest. Etching reduces its rigidity, allowing it to deform appropriately during diaphragm operation.

[0034] The deformation buffer zone is located between the deformation dispersion zone and the intermediate reinforcement zone. The top edge of the dispersion zone 4-1 corresponds to the bottom edge of the triangular boss 3, and the top edge of the stress dispersion zone 5-1 corresponds to the bottom edge of the dispersion zone 4-3, so that the overall deformation of the diaphragm is uniform and long-term local deformation is avoided during the operation of the diaphragm.

[0035] In this embodiment, the number of radial etching grooves 1 is 18. The deformation dispersion region consists of three concentric circumferential reinforcing rings.

[0036] The intermediate reinforcement area occupies about 10% of the area of ​​the etched surface, and the depth of the radial etching groove 1 and the circumferential etching groove 2 is no more than 1 / 2 of the film thickness; so that the film maintains a certain strength.

[0037] The etching process of the film is as follows:

[0038] Step 1: Select Inconel 718 alloy as the diaphragm material with a thickness of 0.3 mm. Polish the metal sheet to ensure a surface roughness Ra ≤ 0.2 μm, which will facilitate the subsequent laser etching process.

[0039] Step 2: Use an ultraviolet laser (wavelength 355 nm) for etching, set the laser power to 10 W, the scanning speed to 500 mm / s, and the pulse frequency to 50 kHz.

[0040] Several radial etching grooves 1 were etched on the surface of the film, with a stripe width of 50 μm and a depth of 0.1 mm (approximately 1 / 3 of the film thickness), and several circumferential etching grooves 2 were etched.

[0041] Step 3:

[0042] After etching, the film is cleaned with an ultrasonic cleaner using anhydrous ethanol as the medium to remove residual metal debris and oxide layer from the surface, and then dried in a vacuum environment.

[0043] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of this utility model, and the utility model is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of this utility model, and these modifications and improvements are also considered to be within the protection scope of this utility model.

Claims

1. A uniformly deformable capacitive pressure sensor diaphragm, comprising a diaphragm body, characterized in that, One side of the film is an etched surface, and the other side is a flat surface. Several radial etching grooves (1) are etched evenly in a central radial pattern on the etched surface, and several circumferential etching grooves (2) are etched evenly in a central annular pattern on the etched surface. The radial etching grooves (1) and the circumferential etching grooves (2) divide the etched surface into an intermediate reinforcement zone, a deformation buffer zone, and a deformation dispersion zone from the inside to the outside. The intermediate reinforcement zone is composed of several triangular protrusions (3) arranged in a ring. The deformation buffer zone is composed of several buffer quadrilateral protrusions (4). The buffer quadrilateral protrusions (4) include a buffer top edge (4-1), a buffer side edge (4-2), and a buffer bottom edge (4-3). The buffer side edges (4-2) are symmetrically arranged and shrink towards the center of the film. The buffer top edge (4-1) connects to the inner ends of the two buffer side edges (4-2), and the buffer bottom edge (4-3) connects to the outer ends of the two buffer side edges (4-2). The buffer top edge (4-1) is a straight line, and the buffer bottom edge (4-3) is an arc. The outer periphery of the deformation dispersion zone is a welding ring surface (6).

2. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The membrane is a circular metal substrate.

3. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The triangular protrusion (3) is an isosceles triangle with its vertex pointing to the center of the membrane.

4. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The deformation dispersion zone is composed of several concentric circumferential reinforcing rings. Each circumferential reinforcing ring is composed of several annular deformation dispersion quadrilateral protrusions (5). The annular deformation dispersion quadrilateral protrusions (5) include a deformation dispersion top edge (5-1), a deformation dispersion side edge (5-2), and a deformation dispersion bottom edge (5-3). The deformation dispersion side edges (5-2) are symmetrically arranged and contract towards the center of the membrane. The deformation dispersion top edge (5-1) connects to the inner ends of the two deformation dispersion side edges (5-2), and the deformation dispersion bottom edge (5-3) connects to the outer ends of the two deformation dispersion side edges (5-2). The deformation dispersion top edge (5-1) and the deformation dispersion bottom edge (5-3) are arcs.

5. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The surface roughness Ra of the welded annular surface (6) is ≤0.8μm.

6. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The number of radial etching grooves (1) is 18.

7. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The central reinforcement area occupies approximately 10% of the etched surface area.

8. The uniformly deformable capacitive pressure sensor diaphragm as described in claim 1, characterized in that, The depth of the radial etching groove (1) and the circumferential etching groove (2) is not greater than half the thickness of the film.

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