CN212008404U

CN212008404U - Zirconia-based micro oxygen concentration sensing element

Info

Publication number: CN212008404U
Application number: CN201921714721.3U
Authority: CN
Inventors: 潘威; 肖红玉; 陈浩远; 张志强; 赵振平; 张铭; 郭子昂
Original assignee: AVIC Shanghai Aeronautical Measurement Controlling Research Institute
Current assignee: AVIC Shanghai Aeronautical Measurement Controlling Research Institute
Priority date: 2019-10-10
Filing date: 2019-10-10
Publication date: 2020-11-24
Anticipated expiration: 2029-10-10

Abstract

The utility model belongs to the technical field of the sensing, a miniature oxygen concentration sensing element based on zirconia is related to. The element comprises: first cassette, second cassette, first electrode ring, second electrode ring, third electrode ring and first zirconia piece, second zirconia piece, wherein, according to the order of first cassette, first electrode ring, first zirconia piece, second electrode ring, second zirconia piece, third electrode ring, second cassette to in proper order the centering stack, first electrode ring and first cassette and first zirconia piece form the cavity, and second electrode ring and first zirconia piece and second cassette form the cavity, and third electrode ring and second zirconia piece and second cassette form the cavity, first cassette, second cassette, first electrode ring, second electrode ring, third electrode ring and first zirconia piece, second zirconia piece are through sintering and are combined.

Description

Zirconia-based micro oxygen concentration sensing element

Technical Field

The invention belongs to the technical field of sensing, and particularly relates to a zirconia-based micro oxygen concentration sensing element.

Background

In the flying process of the airplane, the oxygen partial pressure value in the oxygen system needs to be monitored at any time for controlling the oxygen partial pressure and ensuring that the oxygen supplied to a pilot is in a comfortable and safe state. At present, the oxygen concentration sensing element basically adopts a sleeve type and a plate type, the sleeve type is large in volume, and only qualitative detection can be carried out; the flat plate type mounting size is large, the welding spot strength is low, and the flat plate type mounting structure is difficult to endure the aeromechanical stress environment. And the sensing elements in the two forms generally adopt atmosphere as reference gas, are only suitable for ground equipment such as automobiles, boilers and the like, and the atmosphere of aviation products is variable along with the height, is not constant and is not suitable for aviation products.

Disclosure of Invention

The purpose of the invention is as follows: provided is a micro oxygen concentration sensor element having high accuracy, high reliability, and high environmental suitability.

The technical scheme of the invention is as follows:

in a first aspect, there is provided a zirconia-based micro oxygen concentration sensing element comprising: a first filter sheet 1, a second filter sheet 1.1, a first electrode ring 2, a second electrode ring 2.1, a third electrode ring 2.2, a first zirconium oxide sheet 3 and a second zirconium oxide sheet 3.1, wherein, the first filter sheet 1, the first electrode ring 2, the first zirconium oxide sheet 3, the second electrode ring 2.1, the second zirconium oxide sheet 3.1, the third electrode ring 2.2 and the second filter sheet 1.1 are sequentially stacked in a centering way, the first electrode ring 2, the first filter plate 1 and the first zirconia plate 3 form a cavity, the second electrode ring 2.1, the first zirconia plate 3 and the second zirconia plate 3.1 form a cavity, the third electrode ring 2.2, the second zirconia plate 3.1 and the second filter plate 1.1 form a cavity, the first filter sheet 1, the second filter sheet 1.1, the first electrode ring 2, the second electrode ring 2.1, the third electrode ring 2.2, the first zirconium oxide sheet 3 and the second zirconium oxide sheet 3.1 are combined by sintering.

Optionally, the method further comprises: a sealing ring 4, said sealing ring 4 being arranged on the side.

Optionally, the first filter sheet 1 and the second filter sheet 1.1 are porous gas permeable filter sheets.

Optionally, the first filter sheet 1 and the second filter sheet 1.1 are alumina filter sheets.

Optionally, the surfaces of the first 3 and second 3.1 zirconia plates in contact with the first 2, second 2.1 and third 2.2 electrode rings are coated with a porous platinum coating.

Optionally, the first electrode ring 2, the second electrode ring 2.1, and the third electrode ring 2.2 are ring structures, and one side of the ring structures is provided with a leading-out terminal.

Optionally, the coverage area of the sealing ring 4 at least comprises the joint of the second electrode ring 2.1 and the first zirconia sheet 3 and the second zirconia sheet 3.1.

Alternatively, the sealing ring 4 is formed on the side of the sensing element by sintering.

The invention has the beneficial effects that: a reference gas chamber of a common zirconia oxygen concentration sensing element is the atmosphere, a miniature closed cavity 5 is manufactured by matching two zirconia sheets 3 and a sealing ring 4 through the annular structure design of an electrode ring 2, and the reference gas chamber is used as the reference gas chamber of the sensing element, so that the problem that the atmosphere cannot be used as the reference gas chamber on an airplane is solved. One of the zirconia pieces 3 can be used for dynamically controlling the oxygen content in the cavity 5, so that the measurement precision and reliability are greatly improved. The integral structure is combined by sintering, a mounting and fixing structure is omitted, the size and the weight of the sensing element are ensured to be smaller, the contact area with the outside and the self inertia are objectively reduced, and the environmental adaptability is improved.

Drawings

FIG. 1 is a schematic structural diagram according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a zirconia sheet according to an embodiment of the present invention.

Detailed Description

The following detailed description is made with reference to the accompanying drawings.

As shown in fig. 1, a micro oxygen concentration sensing element based on zirconia includes a first filter 1, a second filter 1.1, a first electrode ring 2, a second electrode ring 2.1, a third electrode ring 2.2, a first zirconia sheet 3, and a second zirconia sheet 3.1. The surfaces of two sides of the first zirconia piece 3 and the second zirconia piece 3.1 are coated with porous platinum coatings, the first filter sheet 1, the first electrode ring 2, the first zirconia piece 3, the second electrode ring 2.1, the second zirconia piece 3.1, the third electrode ring 2.2 and the second filter sheet 1.1 are sequentially stacked in a centering way, and the sealing ring 4 covers the side surface and is combined by sintering to form a micro-closed cavity 5. Current is led between the first electrode ring 2 and the second electrode ring 2.1 to control the oxygen content in the cavity 5, and the second zirconium dioxide sheet 3.1 between the third electrode ring 2.2 and the second electrode ring 2.1 induces the oxygen concentration difference between the cavity 5 and the outside to generate concentration electromotive force which is output through the leading-out end of the electrode ring 2.

The first filter sheet 1 and the second filter sheet 1.1 are arranged, and porous air-permeable materials such as alumina are adopted, so that the gas to be detected outside can be uniformly diffused to the surfaces of the first zirconia sheet 3 and the second zirconia sheet 3.1, particle impurities are filtered, and the measurement accuracy, stability and reliability are improved.

As shown in fig. 2, the surface of the zirconia sheet in contact with the electrode ring is coated with a porous platinum coating, which does not block the contact between oxygen and the zirconia sheet, and plays a catalytic role in the interconversion between oxygen and oxygen ions, thereby improving the measurement sensitivity.

The electrode ring is set to be of an annular structure, the electrode ring is matched with the two zirconium oxide sheets and the sealing ring to objectively form a miniature closed cavity 5, the oxygen content in the cavity 5 can be adjusted by adjusting the current introduced between the electrode rings, the electrode ring serves as a reference gas chamber, the influence of external factors on the reference gas chamber is eliminated, and the measurement precision and the environmental adaptability are improved.

The sensing element is combined by sintering, the size and the weight are very small, the contact area with the outside and the self inertia are objectively reduced, the response of the sensing element to the sensing element is very weak under the influence of the temperature, the humidity, the vacuum degree, particles, mechanical impact and the like of the external environment, and the environmental adaptability and the reliability are improved.

Claims

1. A zirconia-based miniature oxygen concentration sensing element comprising: the filter comprises a first filter plate (1), a second filter plate (1.1), a first electrode ring (2), a second electrode ring (2.1), a third electrode ring (2.2), a first zirconium oxide sheet (3) and a second zirconium oxide sheet (3.1), wherein the first filter plate (1), the first electrode ring (2), the first zirconium oxide sheet (3), the second electrode ring (2.1), the second zirconium oxide sheet (3.1), the third electrode ring (2.2) and the second filter plate (1.1) are sequentially stacked in a centering manner, the first electrode ring (2), the first filter plate (1) and the first zirconium oxide sheet (3) form a cavity, the second electrode ring (2.1), the first zirconium oxide sheet (3) and the second zirconium oxide sheet (3.1) form a cavity, the third electrode ring (2.2), the second zirconium oxide sheet (3.1) and the second filter plate (1.1) form a cavity, and the first filter plate (1), the second filter plate (1.1), the second electrode ring (1.1.1) and the second zirconium oxide sheet (3.1) form a cavity, The first electrode ring (2), the second electrode ring (2.1), the third electrode ring (2.2), the first zirconium oxide sheet (3) and the second zirconium oxide sheet (3.1) are combined through sintering.

2. The sensing element of claim 1, further comprising: a sealing ring (4), the sealing ring (4) being arranged on the side face.

3. The sensor element according to claim 1, characterized in that the first filter sheet (1) and the second filter sheet (1.1) are porous, gas-permeable filter sheets.

4. The sensor element according to claim 1, characterized in that the first filter sheet (1) and the second filter sheet (1.1) are alumina filter sheets.

5. The sensor element according to claim 1, characterized in that the surfaces of the first (3) and second (3.1) zirconium oxide flakes in contact with the first (2), second (2.1) and third (2.2) electrode rings are coated with a porous platinum coating.

6. The sensor element according to claim 1, wherein the first electrode ring (2), the second electrode ring (2.1) and the third electrode ring (2.2) are of an annular structure, and one side of the annular structure is provided with a leading-out terminal.

7. The sensor element according to claim 2, characterized in that the sealing ring (4) covers at least the joint of the second electrode ring (2.1) with the first (3) and second (3.1) zirconia plates.

8. The sensor element according to claim 2 or 7, characterized in that the sealing ring (4) is formed on the side of the sensor element by sintering.