A low stress air pressure sensor calibration fixture

Abstract

The utility model discloses a kind of low stress air pressure sensor calibration tool, it is related to air pressure sensor technical field, including air supply pressure plate and the signal adapter plate located below air supply pressure plate, the bottom of air supply pressure plate is communicated with air nozzle, the top of signal adapter plate is provided with limit card slot, limit card slot is provided with probe hole and spring probe in its inside, spring probe one end is set in limit card slot through probe hole, the other end of spring probe is welded with signal adapter plate, differential pressure sensor, by air supply pressure plate and air nozzle constitute pressure supply passage, limit card slot realizes sensor positioning, spring probe and signal adapter plate complete electric signal transmission;Through air inlet and air hole cooperation, the pressure difference adjustment of differential pressure sensor both ends is realized, then through thread, elastic silica gel pad and spring type silica gel suction disc, respectively guarantee the sealing of air nozzle and air supply pressure plate, air nozzle and differential pressure sensor.

Description

Technical Field

[0001] This utility model relates to the field of air pressure sensor technology, specifically a low-stress air pressure sensor calibration fixture. Background Technology

[0002] MEMS (Micro-Electro-Mechanical System) pressure sensors have many advantages, such as high sensitivity, small size, low power consumption, good consistency, and ease of mass production. They are widely used in industrial production, automotive electronics, biomedicine, defense, scientific research, and aerospace. MEMS pressure sensor calibration and testing requires applying specific pressure and temperature standards (usually several different pressure and temperature points covering the full range of the sensor) to adjust or verify the sensor's gain or bias at these specific temperatures and pressures, ensuring that the output value corresponds accurately throughout the entire range to achieve the desired linearity or accuracy.

[0003] In existing technologies, the design of calibration fixtures for MEMS differential pressure sensors is extremely difficult, mainly due to the following three aspects: ① MEMS differential pressure sensors require precise control of dual independent pressure loops, making it impossible to enclose multiple products in a single sealed cavity for pressure control, which leads to difficulties in mass calibration; ② Currently, differential pressure sensor calibration and testing fixtures mostly use compression or clamping methods to achieve sealing, resulting in extremely high stress on the product during calibration and testing. This causes non-pressure-induced changes in the pressure-sensitive diaphragm inside the MEMS chip, resulting in large performance deviations and poor consistency.

[0004] Based on this, a low-stress air pressure sensor calibration fixture is now provided, which can eliminate the drawbacks of existing devices. Utility Model Content

[0005] The purpose of this invention is to provide a low-stress air pressure sensor calibration fixture to solve the problems in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A low-stress air pressure sensor calibration fixture includes an air supply plate and a signal adapter plate located below the air supply plate. The bottom of the air supply plate is connected to an air nozzle. The top of the signal adapter plate is provided with a limit slot. The limit slot is provided with a probe hole and a spring probe. One end of the spring probe is set in the limit slot through the probe hole, and the other end of the spring probe is welded to the signal adapter plate. The differential pressure sensor is set inside the limit slot, and the pad position of the differential pressure sensor corresponds to the position of the spring probe.

[0008] Based on the above technical solutions, this utility model also provides the following optional technical solutions:

[0009] In one alternative: the air supply pressure plate is provided with an air inlet, the bottom of the signal adapter plate is provided with a vent, and the other end of the differential pressure sensor is connected to the outside gas through the vent.

[0010] In one alternative: the top of the air nozzle is provided with threads and an elastic silicone pad, and the bottom of the air supply pressure plate is provided with a threaded hole that matches the threads.

[0011] In one alternative: the bottom end of the air nozzle is provided with a spring-loaded silicone suction cup that contacts the housing of the air supply pressure plate.

[0012] In one alternative: the tooling structure consisting of the air supply pressure plate, air nozzle, limit slot, spring probe and signal adapter board is a batch array structure, used to calibrate and test multiple differential pressure sensors simultaneously.

[0013] In one alternative: the spring probe is made of a flexible metal material.

[0014] In one alternative: the elastic silicone pad is made of silicone material that is resistant to aging and has good sealing properties.

[0015] In one alternative: the spring-loaded silicone suction cup is made of silicone material combined with a built-in spring.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1. This utility model uses a low-stress air pressure sensor calibration fixture, which forms a pressure supply channel through an air supply plate and an air nozzle, uses a limit slot to position the sensor, and uses a spring probe and a signal adapter plate to transmit electrical signals; the differential pressure sensor can be adjusted by the cooperation of an air inlet and an air outlet.

[0018] 2. This utility model uses a low-stress air pressure sensor calibration fixture, which uses threads, elastic silicone pads and spring-type silicone suction cups to ensure the sealing between the air nozzle and the air supply pressure plate, and between the air nozzle and the differential pressure sensor. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0020] Figure 2 This is a schematic diagram of some of the components of this utility model.

[0021] Figure 3 This is a schematic diagram of the structure of the air nozzle in this utility model.

[0022] Figure 4 This is a cross-sectional structural diagram of the present invention.

[0023] Figure label annotations: 1. Air supply pressure plate; 11. Air inlet; 2. Air nozzle; 21. Thread; 22. Elastic silicone pad; 23. Spring-type silicone suction cup; 3. Limiting slot; 4. Spring probe; 41. Vent hole; 5. Signal adapter board; 6. Differential pressure sensor. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] In one embodiment, such as Figures 1-4 As shown, a low-stress air pressure sensor calibration fixture includes an air supply plate 1 and a signal adapter plate 5 located below the air supply plate 1. The bottom of the air supply plate 1 is connected to an air nozzle 2. The top of the signal adapter plate 5 is provided with a limit slot 3. The limit slot 3 is provided with a probe hole and a spring probe 4. One end of the spring probe 4 is set in the limit slot 3 through the probe hole, and the other end of the spring probe 4 is welded to the signal adapter plate 5. A differential pressure sensor 6 is set inside the limit slot 3, and the pad position of the differential pressure sensor 6 corresponds to the position of the spring probe 4.

[0026] In this embodiment, the air pressure plate 1 serves as the air pressure supply component, and the air nozzle 2 connected to its bottom is the air pressure conduction channel. The two work together to deliver the pressure source required for calibration to the differential pressure sensor 6. The limiting slot 3 on the top of the signal adapter plate 5 positions the differential pressure sensor 6 to ensure stable placement of the sensor. At the same time, the probe hole in the limiting slot 3 provides installation space for the spring probe 4. One end of the spring probe 4 passes through the probe hole and is placed in the limiting slot 3, corresponding to the pad position of the differential pressure sensor 6. The other end is welded to the signal adapter plate 5. When the differential pressure sensor 6 is placed in the limiting slot 3, the electrical signal of the sensor is transmitted to the signal adapter plate 5, providing a basis for reading calibration data.

[0027] In one embodiment, such as Figure 4 As shown, the air supply pressure plate 1 is provided with an air inlet 11, and the bottom of the signal adapter plate 5 is provided with a vent 41. The other end of the differential pressure sensor 6 is connected to the outside gas through the vent 41.

[0028] The air inlet 11 on the air supply plate 1 is used to connect to the external pressurized gas. The gas enters one end of the differential pressure sensor 6 through the air nozzle 2, so that the pressure at that end can be controlled and adjusted. The vent 41 at the bottom of the signal adapter board 5 allows the other end of the differential pressure sensor 6 to communicate with the outside atmosphere. By adjusting the pressure of the pressurized gas through the pressure controller, the pressure difference between the two ends of the differential pressure sensor 6 can be changed to meet the test requirements of different calibration pressure points.

[0029] In one embodiment, such as Figure 3 and Figure 4 As shown, the top of the air nozzle 2 is provided with a thread 21 and an elastic silicone pad 22, and the bottom of the air pressure plate 1 is provided with a threaded hole that matches the thread 21.

[0030] The thread 21 at the top of the air nozzle 2 engages with the matching threaded hole at the bottom of the air supply pressure plate 1. Rotating the air nozzle 2 can lock it in place, ensuring a stable structural connection. At the same time, the elastic silicone pad 22 at the top of the air nozzle 2 is squeezed during the locking process of the thread 21. The elasticity of the silicone tightly adheres to the contact surface between the air nozzle 2 and the air supply pressure plate 1, filling the gap and preventing the pressurized gas from leaking from the connection between the two, thus ensuring the accuracy of air pressure transmission.

[0031] In one embodiment, such as Figure 3 As shown, the bottom end of the air nozzle 2 is provided with a spring-type silicone suction cup 23 that contacts the housing of the air supply pressure plate 1;

[0032] The spring-loaded silicone suction cup 23 at the bottom of the air nozzle 2 combines the sealing properties of silicone with the elasticity of a spring. When the air supply plate 1 is pressed down, the spring-loaded silicone suction cup 23 contacts the housing of the differential pressure sensor 6. The continuous downward pressure compresses the spring inside the suction cup, causing the silicone part to contract and tightly wrap around the sensor contact area. This avoids excessive stress on the differential pressure sensor 6 caused by traditional compression or clamping seals, ensuring a leak-proof seal while protecting the internal pressure-sensitive diaphragm of the sensor from additional stress, thus ensuring accurate calibration data.

[0033] In one embodiment, such as Figure 2 As shown, the tooling structure consisting of the air supply pressure plate 1, air nozzle 2, limit slot 3, spring probe 4 and signal adapter board 5 is a batch array structure, used to simultaneously calibrate and test multiple differential pressure sensors 6.

[0034] The air supply pressure plate 1, air nozzle 2, limit slot 3, spring probe 4, and signal adapter board 5 are replicated to the same specifications to form a batch array structure. Each array unit has the function of independently calibrating a single differential pressure sensor 6. During operation, multiple differential pressure sensors 6 can be placed into their corresponding limit slots 3 simultaneously. The air nozzles 2 of each unit synchronously transmit air pressure, and the spring probes 4 synchronously establish electrical connections, enabling parallel calibration of multiple sensors. This solves the problem of difficult batch processing using traditional tooling and significantly improves calibration efficiency.

[0035] In one embodiment, such as Figure 4 As shown, the spring probe 4 is made of a flexible metal material.

[0036] The spring probe 4 is made of a flexible metal material, which ensures good conductivity and can efficiently transmit the electrical signal of the differential pressure sensor 6. The elasticity allows the spring probe 4 to be smoothly pressed down when the differential pressure sensor 6 is placed in the limiting slot 3, and to fit tightly against the sensor pad position. During the calibration process, even if it is subjected to slight vibration or positional deviation, the elasticity can keep the probe in contact with the pad, avoid the interruption of electrical connection, and ensure continuous and stable transmission of electrical signal.

[0037] In one embodiment, such as Figure 3 As shown, the elastic silicone pad 22 is made of silicone material that is resistant to aging and has good sealing properties;

[0038] The elastic silicone pad 22 is made of silicone material that is resistant to aging and has good sealing properties. Its good sealing properties effectively prevent gas leakage under compression, ensuring the accuracy of air pressure transmission. Its aging resistance ensures that the elastic silicone pad 22 is not prone to hardening or cracking due to temperature changes or gas corrosion during long-term use, thus extending the life of the sealing components, maintaining the long-term stable sealing performance of the tooling, and reducing calibration errors caused by seal failure.

[0039] In one embodiment, such as Figure 3 As shown, the spring-loaded silicone suction cup 23 is made of silicone material combined with a built-in spring;

[0040] The spring-loaded silicone suction cup 23 is composed of silicone material and an internal spring. The silicone material provides basic sealing capability to ensure an effective sealing surface when in contact with the housing of the differential pressure sensor 6. The internal spring provides elastic support for the suction cup. When the pressure plate 1 is pressed down, the spring can flexibly extend and retract according to the pressure, causing the silicone suction cup to shrink adaptively. This ensures a tight fit with the sensor while avoiding damage to the sensor due to excessive pressure. At the same time, the spring's reset capability allows the suction cup to return to its original shape after calibration, facilitating the removal and placement of the differential pressure sensor 6 and improving operational convenience.

[0041] The above embodiments disclose a low-stress air pressure sensor calibration fixture, wherein the air supply plate 1 and the air nozzle 2 constitute a pressure supply channel, the limiting slot 3 realizes sensor positioning, and the spring probe 4 and the signal adapter plate 5 complete the electrical signal transmission; the pressure difference between the two ends of the differential pressure sensor 6 is adjusted by the cooperation of the air inlet 11 and the air outlet 41; the thread 21, the elastic silicone pad 22 and the spring-type silicone suction cup 23 are used to ensure the sealing between the air nozzle 2 and the air supply plate 1, and between the air nozzle 2 and the differential pressure sensor 6, respectively.

[0042] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A low-stress air pressure sensor calibration fixture, characterized in that, The system includes an air supply pressure plate (1) and a signal adapter plate (5) located below the air supply pressure plate (1). The bottom of the air supply pressure plate (1) is connected to an air nozzle (2). The top of the signal adapter plate (5) is provided with a limit slot (3). The limit slot (3) is provided with a probe hole and a spring probe (4). One end of the spring probe (4) is set in the limit slot (3) through the probe hole. The other end of the spring probe (4) is welded to the signal adapter plate (5). The limit slot (3) is provided with a differential pressure sensor (6), and the pad position of the differential pressure sensor (6) corresponds to the position of the spring probe (4).

2. The low-stress air pressure sensor calibration fixture according to claim 1, characterized in that, The air supply pressure plate (1) is provided with an air inlet (11), and the bottom of the signal adapter plate (5) is provided with a vent (41). The other end of the differential pressure sensor (6) is connected to the outside gas through the vent (41).

3. The low-stress air pressure sensor calibration fixture according to claim 1, characterized in that, The top of the air nozzle (2) is provided with a thread (21) and an elastic silicone pad (22), and the bottom of the air supply pressure plate (1) is provided with a threaded hole that matches the thread (21).

4. The low-stress gas pressure sensor calibration fixture according to claim 1, characterized in that, The bottom end of the air nozzle (2) is provided with a spring-type silicone suction cup (23) that contacts the housing of the air supply pressure plate (1).

5. The low-stress gas pressure sensor calibration fixture according to claim 1, characterized in that, The tooling structure consisting of the air supply pressure plate (1), air nozzle (2), limit slot (3), spring probe (4) and signal adapter plate (5) is a batch array structure, used to simultaneously calibrate and test multiple differential pressure sensors (6).

6. The low-stress air pressure sensor calibration fixture according to claim 1, characterized in that, The spring probe (4) is made of a flexible metal material.

7. The low-stress air pressure sensor calibration fixture according to claim 3, characterized in that, The elastic silicone pad (22) is made of aging-resistant silicone material.

8. The low-stress air pressure sensor calibration fixture according to claim 4, characterized in that, The spring-loaded silicone suction cup (23) is made of silicone material and a built-in spring.

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