Test fixture for miniature silicon piezoresistive differential pressure sensor

Abstract

The invention belongs to the technical field of sensor detection, and particularly relates to a test fixture for a miniature silicon piezoresistive differential pressure sensor, which comprises a base, a sliding groove is formed in the surface of the base, a plurality of first clamping plates and second clamping plates are slidably connected in the sliding groove, the base is fixedly connected with a plurality of supports, and a supporting block is slidably connected in each support. A plurality of sets of clamping jaw seats are fixedly connected to the base, two sets of clamping jaws are hinged to each set of clamping jaw seat, and a V-shaped notch used for supporting and placing a silicon piezoresistive differential pressure sensor is formed in the top of each supporting block. And a group of oppositely arranged accommodating cavities are fixedly connected to the corresponding positions of the two ends of the silicon piezoresistive differential pressure sensor on each group of opposite first clamping plate and second clamping plate. The clamping jaw is arranged for pre-clamping and positioning, and the wire buckling sheet is used for clamping and limiting the wire of the silicon piezoresistive differential pressure sensor, so that the problems that an operator needs to pay attention and repeatedly adjust the wire due to unstable placement or inclination and falling caused by accidental touch are avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensor detection, and specifically relates to a test fixture for a micro silicon piezoresistive differential pressure sensor. Background Art

[0002] A differential pressure sensor is a device used to measure the pressure difference between two different positions, which can convert the pressure difference value into an electrical signal output and is widely used in fields such as industry, medical treatment, and environmental monitoring. With the progress and development of technology, the differential pressure sensor is also developing towards miniaturization or microminiaturization. The structure of the differential pressure sensor is more compact and the degree of integration is higher, thus broadening the application scenarios of the differential pressure sensor, such as portable medical devices, intelligent monitoring devices, new energy vehicle sensors, pressure nodes in industrial Internet of Things, etc.

[0003] Differential pressure sensors can be classified into piezoresistive differential pressure sensors, capacitive differential pressure sensors, resonant differential pressure sensors, inductive differential pressure sensors, etc. according to their sensing principles. Among them, piezoresistive differential pressure sensors are widely used due to their high sensitivity and the characteristics of simple structure and easy microminiaturization, and their production cost and processing difficulty are low, resulting in a very large output.

[0004] After the production of differential pressure sensors, it is usually necessary to conduct sampling inspection and testing on the batch-produced differential pressure to test whether the readings of the differential pressure sensors are accurate and whether the numerical fluctuations exceed the acceptable range, and to calculate the production yield rate of the differential pressure sensors based on the test results, so as to feedback to the production workshop to optimize the production and processing technology.

[0005] The most traditional method for testing differential pressure sensors generally uses a method of clamping a single sensor with a pair of chambers. The operator places a single sensor to be detected in the test fixture, connects the wire of the differential pressure sensor to the detection system, and then drives the fixture to clamp and seal the high-pressure end and low-pressure end of the sensor, and applies high-pressure and low-pressure conditions respectively to detect the parameters and quality of the sensor. However, this manual detection method one by one is troublesome and inefficient, and the method of single-piece assembly fixture can no longer meet the production requirements of batch testing. Therefore, a fixture that can clamp and detect multiple sensors simultaneously is needed.

[0006] As disclosed in Chinese Patent No. CN101424577B, a test fixture for preparing a silicon capacitive differential pressure sensor is described, including horizontal, positioning, clamping, gas circuit, and sealing parts. The left chamber, six intermediate chambers, and right chamber are sequentially placed between the left support seat and the right support seat. Seven V-shaped supports are respectively placed between the chambers. The guide rod passes through the guide rod holes on the chambers, V-shaped supports, left support seat, and right support seat and is fixed. The compression screw passes through the right support seat and is sleeved with a compression seat to form a clamping mechanism. This test fixture can clamp 7 sensors at one time and perform pressure tests simultaneously to meet the test requirements of mass production.

[0007] However, when it comes to small or miniaturized differential pressure sensors, the above patent will encounter the following problems:

[0008] 1. Miniature sensors are small in size and light in weight. During the initial placement, they are easily affected by human operation and it is difficult to stably place them on their V-shaped supports. Then, in the process of controlling the mutual approach of each chamber to clamp and seal both ends of the differential pressure sensor, it is difficult for the above patent to ensure that each sensor can be accurately clamped and sealed, affecting the clamping stability and accuracy. And if the positions of each differential pressure sensor are adjusted repeatedly, it will waste time, which is contradictory to the purpose of accelerating the clamping detection speed and improving the efficiency of batch testing.

[0009] 2. Generally, wires will extend from miniature sensors. Due to their small size and light weight, the weight of the wires accounts for a relatively large proportion of the overall weight of the sensors. The above patent cannot clamp and restrict the wires, making the sensor body easily fall off or drop from the V-shaped support due to the influence of the wire weight when placing the sensor. Furthermore, it makes the operator have to be more careful and attentive during placement, causing a work burden on the operator. And the scattered wires are not convenient for the operator to perform wiring operations, thus affecting the detection. Summary of the Invention

[0010] In order to overcome the deficiencies of the prior art, the technical problem to be solved by the present invention is that by providing multiple sets of first clamping plates and second clamping plates, multiple silicon piezoresistive differential pressure sensors can be clamped and tested simultaneously, thereby improving the testing efficiency and realizing the timely and efficient feedback in the production of silicon piezoresistive differential pressure sensors. By providing clamping jaws, pre-clamping and positioning of the silicon piezoresistive differential pressure sensor can be performed in cooperation with the support block before final clamping, and the position of the silicon piezoresistive differential pressure sensor is accurately positioned with the cavity, so as to ensure that when clamping and sleeving both ends of multiple silicon piezoresistive differential pressure sensors simultaneously subsequently, each silicon piezoresistive differential pressure sensor can accurately enter the cavity, ensuring the stability and accuracy of the clamping process. By providing a clamping arm and a wire-clamping piece, the weight of the wire is prevented from causing the silicon piezoresistive differential pressure sensor to skew and the silicon piezoresistive differential pressure sensor to be misaligned with the cavity, and the wire-clamping piece clamps and restricts the wire, enabling the multiple wires corresponding to each silicon piezoresistive differential pressure sensor to be bundled together, facilitating the operator to distinguish the wires corresponding to different silicon piezoresistive differential pressure sensors and also facilitating the operator to distinguish each wire on the same silicon piezoresistive differential pressure sensor, so as to facilitate the operator to perform wiring operations. By connecting the support block and the clamping jaw through a second sliding pin and a second straight groove, the pre-clamping action is automatically completed while placing the silicon piezoresistive differential pressure sensor, and by using a pressing piece and a hook-tooth plate, when the first clamping plate and the second clamping plate move away from each other to release the clamping of the silicon piezoresistive differential pressure sensor, the support block is automatically jacked up and the clamping jaw is opened, realizing a fast and automatic blanking action, which greatly saves the operation actions of the operator, saves the clamping time, improves the testing efficiency, and reduces the working burden of the operator.

[0011] In order to achieve the above object, the present invention provides the following technical solution: A test fixture for a micro silicon piezoresistive differential pressure sensor, comprising:

[0012] A base and a silicon piezoresistive differential pressure sensor. A chute is formed on the surface of the base, and a plurality of first clamping plates and second clamping plates are slidably connected in the chute. The first clamping plates and the second clamping plates are arranged in pairs opposite to each other;

[0013] A support. A support is fixedly connected between each pair of opposite first clamping plates and second clamping plates on the base. A support block is slidably connected in each support. A set of clamping jaw seats is fixedly connected to both sides of each support on the base. Two sets of oppositely arranged clamping jaws for clamping the silicon piezoresistive differential pressure sensor are respectively hinged on each set of clamping jaw seats;

[0014] Wherein, a V-shaped notch for supporting and placing the silicon piezoresistive differential pressure sensor is formed at the top of each support block, and a set of oppositely arranged cavities are fixedly connected at the corresponding positions at both ends of the silicon piezoresistive differential pressure sensor on each pair of opposite first clamping plates and second clamping plates.

[0015] Further, two symmetric arc-shaped grooves are formed in each of the supporting blocks. At the corresponding positions of the two ends of each support, first straight grooves are formed. A first sliding pin that slides in the corresponding arc-shaped groove is slidably connected in each first straight groove. A set of sliding rods are fixedly connected to both ends of each first sliding pin respectively. Slide rod seats are fixedly connected to the two sides of each support at the corresponding positions of the sliding rods. Each sliding rod is slidably connected to the corresponding slide rod seat. A spring surrounding the outer side of the sliding rod is arranged between each sliding rod and the corresponding slide rod seat.

[0016] Further, a set of second straight grooves are formed in each of the supporting blocks below the arc-shaped grooves. A second sliding pin is slidably connected in each set of second straight grooves. Both ends of each second sliding pin are fixedly connected to the corresponding clamping jaw.

[0017] Further, an arc-shaped portion for pressing the silicon piezoresistive differential pressure sensor is arranged at the top of each clamping jaw. The tops of the clamping jaws located on both sides of the support are arranged in an interlaced manner.

[0018] Further, a set of oppositely arranged clamping arms are fixedly connected to the tops of each set of clamping jaws respectively. A set of wire buckling pieces are fixedly connected to the tops of the two oppositely arranged clamping arms respectively. Bent extension parts are arranged at both ends of each wire buckling piece. The extension parts of the two opposite wire buckling pieces are arranged in a staggered manner.

[0019] Further, a first lead screw and a second lead screw are respectively arranged on both sides of the sliding groove on the base. Each first clamping plate is threadedly connected to the second lead screw and slidably connected to the first lead screw. Each second clamping plate is threadedly connected to the first lead screw and slidably connected to the second lead screw. Two sets of lead screw seats are fixedly connected to both ends of the first lead screw and the second lead screw on the base respectively. The two sets of lead screw seats are respectively rotatably connected to the first lead screw and the second lead screw. Handwheels are fixedly connected to the ends of the first lead screw and the second lead screw extending out of the lead screw seats.

[0020] Further, a pressing piece is connected to the bottom of each supporting block. A set of inclined tooth blocks are fixedly connected to the base at the positions below each pressing piece. A hook tooth plate is slidably connected in the sliding groove between each set of inclined tooth blocks. The tooth tip inclined surface of each hook tooth plate is parallel to the inclined tooth block. A connection is fixedly established between each hook tooth plate and the corresponding first clamping plate.

[0021] Further, a second clamping plate is fixedly connected to one end of each cavity away from the silicon piezoresistive differential pressure sensor. Each second clamping plate is internally communicated with the corresponding cavity. A set of sealing rings are fixedly connected to the inner wall of one end of each cavity close to the silicon piezoresistive differential pressure sensor.

[0022] Further, two groups of pressure-resistant hoses are fixedly connected to both sides of the base respectively. An air pressure tube is fixedly connected inside each group of pressure-resistant hoses. The two air pressure tubes are respectively filled with high-pressure air and low-pressure air. Two cavities located on the first clamping plate and the second clamping plate respectively are connected to the two air pressure tubes through communication connections.

[0023] In summary, compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] (1) By setting multiple groups of the first clamping plate and the second clamping plate, multiple silicon piezoresistive differential pressure sensors can be clamped and tested simultaneously, thereby improving the testing efficiency and realizing the timely and efficient feedback in the production of silicon piezoresistive differential pressure sensors.

[0025] (2) By setting the clamping jaws, pre-clamping and positioning of the silicon piezoresistive differential pressure sensor can be performed in cooperation with the support block before final clamping. The position of the silicon piezoresistive differential pressure sensor is accurately positioned with the cavity, so as to ensure that when clamping and sleeving both ends of multiple silicon piezoresistive differential pressure sensors simultaneously subsequently, each silicon piezoresistive differential pressure sensor can accurately enter the cavity, ensuring the stability and accuracy of the clamping process.

[0026] (3) By setting the clamping arm and the wire buckling piece, the weight of the wire is avoided from causing the silicon piezoresistive differential pressure sensor to skew and the silicon piezoresistive differential pressure sensor to be misaligned with the cavity. And the wire buckling piece clamps and restricts the wire, enabling the multiple wires corresponding to each silicon piezoresistive differential pressure sensor to be bundled together, which is convenient for the operator to distinguish the wires corresponding to different silicon piezoresistive differential pressure sensors, and is also convenient for the operator to distinguish the wires on the same silicon piezoresistive differential pressure sensor, so as to facilitate the operator's wiring operation.

[0027] (4) By connecting the support block and the clamping jaws through the second sliding pin and the second straight groove, the pre-clamping action is automatically completed while placing the silicon piezoresistive differential pressure sensor, and by using the abutting piece and the hook tooth plate, when the first clamping plate and the second clamping plate move away from each other to release the clamping of the silicon piezoresistive differential pressure sensor, the support block is automatically jacked up and the clamping jaws are opened, realizing a fast and automatic blanking action, which greatly saves the operator's operation actions, saves the clamping time, improves the testing efficiency, and reduces the operator's work burden. Description of the Drawings

[0028] Figure 1 is the three-dimensional schematic diagram of this patent.

[0029] Figure 2 is the top view of this patent.

[0030] Figure 3 is Figure 2 the three-dimensional sectional view at A-A in

[0031] Figure 4 isFigure 3 Partial enlarged view at position B in [the figure].

[0032] Figure 5 Schematic structural diagram of the main mechanism of this patent.

[0033] Figure 6 is Figure 5 Partial enlarged view at position C in [the figure].

[0034] Figure 7 Schematic structural diagram when the clamping jaws are closed.

[0035] Figure 8 Schematic structural diagram when the clamping jaws are open.

[0036] Figure 9 Schematic structural diagram of the support and the support block.

[0037] Explanation of reference numerals in the drawings: Base 10; Support 11; Support block 12; V-shaped notch 13; Silicon piezoresistive differential pressure sensor 14; Arc-shaped groove 15; First straight groove 16; First sliding pin 17; Slide bar 18; Spring 19; Slide bar seat 20; Clamping jaw 21; Clamping jaw seat 22; Second sliding pin 23; Second straight groove 24; Contact piece 25; Hook tooth plate 26; Helical tooth block 27; Clamping arm 28; Wire buckling piece 29; Slide groove 30; First clamping plate 31; Cavity 32; Connecting cap 33; Sealing ring 34; Second clamping plate 35; First lead screw 36; Second lead screw 37; Lead screw seat 38; Handwheel 39; Pneumatic tube 40; Pressure-resistant hose 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69; 70. Detailed implementation manners

[0038] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0039] Such as Figures 1-9As shown in the figure, a test fixture for a micro silicon piezoresistive differential pressure sensor includes a base 10. A chute 30 is provided on the base 10. A plurality of first clamping plates 31 and second clamping plates 35 are respectively slidably connected in the chute 30. The first clamping plates 31 and the second clamping plates 35 are arranged alternately and opposite to each other in pairs. Oppositely arranged cavities 32 are respectively fixedly connected to each first clamping plate 31 and the corresponding second clamping plate 35, and high-pressure air and low-pressure air are respectively introduced into the cavities 32. A support 11 is fixedly connected to the base 10 at a position between each pair of relatively arranged first clamping plates 31 and second clamping plates 35. A support block 12 is slidably connected in the support 11. A V-shaped notch 13 is provided at the top of the support block 12. A silicon piezoresistive differential pressure sensor 14 is placed on each V-shaped notch 13. The two ends of each cavity 32 correspond to the two ends of the silicon piezoresistive differential pressure sensor 14. One end of each cavity 32 away from the silicon piezoresistive differential pressure sensor 14 is fixedly connected to a second clamping plate 35. Each second clamping plate 35 is internally communicated with the corresponding cavity 32. A group of sealing rings 34 are fixedly connected to the inner wall of one end of each cavity 32 close to the silicon piezoresistive differential pressure sensor 14. Two groups of pressure-resistant hoses 41 are respectively fixedly connected to both sides of the base 10. An air pressure pipe 40 is fixedly connected in each group of pressure-resistant hoses 41. High-pressure air and low-pressure air are respectively introduced into the two air pressure pipes 40. The two cavities 32 respectively located on the first clamping plate 31 and the second clamping plate 35 are respectively connected to the two air pressure pipes 40 through 42 for connection.

[0040] By providing the first clamping plate 31 and the second clamping plate 35, the opposite cavities 32 can clamp and wrap the two ends of the silicon piezoresistive differential pressure sensor 14 respectively, and high-pressure air and low-pressure air are respectively applied, so that the silicon piezoresistive differential pressure sensor 14 can be clamped and parameters such as whether its reading is accurate and whether the numerical fluctuation exceeds the acceptable range can be tested, so as to facilitate estimating the yield rate and feedback adjusting and optimizing the production process.

[0041] As Figures 1-9 shown in the figure, clamping jaw seats 22 are respectively fixedly connected to both sides of the support 11 on the base 10. A group of clamping jaws 21 are hinged on each clamping jaw seat 22. The two groups of clamping jaws 21 located on both sides of the support 11 are arranged oppositely and staggered with each other. An arc-shaped part for pressing on the silicon piezoresistive differential pressure sensor 14 is provided at the top of each group of clamping jaws 21.

[0042] By providing the clamping jaws 21, the silicon piezoresistive differential pressure sensor 14 can be clamped and wrapped in all directions in cooperation with the support block 12. Thus, when the operator places a plurality of silicon piezoresistive differential pressure sensors 14 in sequence, the silicon piezoresistive differential pressure sensor 14 can be pre-positioned to ensure that the two ends of the silicon piezoresistive differential pressure sensor 14 accurately correspond to the cavities 32, which is convenient for the subsequent mutual approach of the first clamping plate 31 and the second clamping plate 35 to seal and clamp the ends of the silicon piezoresistive differential pressure sensor 14.

[0043] As Figures 1-9As shown in the figure, two symmetrically arranged arc-shaped grooves 15 are formed in each support block 12. At the corresponding positions of both ends of each support 11, first straight grooves 16 are formed at the corresponding positions of each arc-shaped groove 15. A first sliding pin 17 that slides in the corresponding arc-shaped groove 15 is slidably connected in each first straight groove 16. A set of sliding rods 18 are fixedly connected to both ends of each first sliding pin 17 respectively. Slide rod seats 20 are fixedly connected to both sides of each support 11 at the corresponding positions of the sliding rods 18. Each sliding rod 18 is slidably connected to the corresponding slide rod seat 20. A spring 19 surrounding the outer side of the sliding rod 18 is arranged between each sliding rod 18 and the corresponding slide rod seat 20. A set of second straight grooves 24 are formed in each support block 12 below the arc-shaped grooves 15. A second sliding pin 23 is slidably connected in each set of second straight grooves 24. Both ends of each second sliding pin 23 are fixedly connected to the corresponding clamping jaw 21.

[0044] By providing the arc-shaped groove 15 and the first sliding pin 17, the elastic force of the spring 19 can be utilized to enable the support block 12 to be in two positions, high and low, and maintain its state. By providing the second sliding pin 23 and the second straight groove 24, the clamping jaws 21 naturally open when the support block 12 is in the high position, and the clamping jaws 21 close to clamp the silicon piezoresistive differential pressure sensor 14 when the support block 12 is in the low position. Thus, when the operator places the silicon piezoresistive differential pressure sensor 14, the support block 12 can be pressed down to automatically clamp and fix the silicon piezoresistive differential pressure sensor 14 without extra steps, with simple and convenient operation, saving the clamping time and improving the testing efficiency.

[0045] Moreover, by the cooperation of the clamping jaws 21 and the support block 12, the silicon piezoresistive differential pressure sensor 14 is kept stable, preventing the silicon piezoresistive differential pressure sensor 14 from falling due to unnecessary collisions, thus ensuring the stability and accuracy of the subsequent process of sleeving the cavity 32 on the end of the silicon piezoresistive differential pressure sensor 14, without the need for the operator to repeatedly adjust, thereby reducing the operator's workload and operation difficulty.

[0046] As Figures 1-9 shown, clamping arms 28 arranged oppositely are fixedly connected to the tops of each set of clamping jaws 21 respectively. A set of wire-clamping pieces 29 are fixedly connected to the tops of the two oppositely arranged clamping arms 28 respectively. Bent extension parts are arranged at both ends of each wire-clamping piece 29. The extension parts of the two oppositely arranged wire-clamping pieces 29 are arranged in a staggered manner.

[0047] By setting the clamping arm 28 and the wire clamping piece 29, while the support block 12 and the clamping jaw 21 clamp and fix the body of the silicon piezoresistive differential pressure sensor 14, the wire clamping piece 29 is used to clamp and limit the wires of the silicon piezoresistive differential pressure sensor 14, thereby preventing the weight of the wires from causing the silicon piezoresistive differential pressure sensor 14 to skew and making the silicon piezoresistive differential pressure sensor 14 misaligned with the cavity 32. Moreover, the wire clamping piece 29 clamps and restricts the wires, enabling the multiple wires corresponding to each silicon piezoresistive differential pressure sensor 14 to be bundled together, facilitating the operator to distinguish the wires corresponding to different silicon piezoresistive differential pressure sensors 14 and also facilitating the operator to distinguish the wires on the same silicon piezoresistive differential pressure sensor 14, so as to facilitate the operator to perform wiring operations.

[0048] As Figures 1-9 shown, a first lead screw 36 and a second lead screw 37 are respectively arranged on both sides of the chute 30 on the base 10. Each first clamping plate 31 is threadedly connected to the second lead screw 37 and slidably connected to the first lead screw 36. Each second clamping plate 35 is threadedly connected to the first lead screw 36 and slidably connected to the second lead screw 37. Two sets of lead screw seats 38 are fixedly connected to both ends of the first lead screw 36 and the second lead screw 37 on the base 10 respectively. The two sets of lead screw seats 38 are respectively rotatably connected to the first lead screw 36 and the second lead screw 37. The ends of the first lead screw 36 and the second lead screw 37 extending out of the lead screw seats 38 are fixedly connected with handwheels 39.

[0049] By setting the first lead screw 36 and the second lead screw 37, the first clamping plate 31 and the second clamping plate 35 can be respectively controlled to move closer to or away from each other, so as to realize the functions of clamping and sealing when the cavity 32 is sleeved on the end of the silicon piezoresistive differential pressure sensor 14. Moreover, using one first lead screw 36 and one second lead screw 37 can simultaneously drive multiple sets of first clamping plates 31 and second clamping plates 35 to move towards each other, simplifying the driving structure and thus reducing the production cost of this fixture.

[0050] As Figures 1-9 shown, a resisting piece 25 is hinged to the bottom of each support block 12. A set of inclined tooth blocks 27 are fixedly connected to the base 10 at positions below each resisting piece 25. A hook tooth plate 26 is slidably connected between each set of inclined tooth blocks 27 in the chute 30. The tooth tip inclined surface of each hook tooth plate 26 is parallel to the inclined tooth block 27. A fixed connection is made between each hook tooth plate 26 and the corresponding first clamping plate 31.

[0051] By setting the resisting piece 25 and the hook tooth plate 26, after the detection is completed, the action of the first clamping plate 31 and the second clamping plate 35 moving away from each other can be utilized. The hook tooth plate 26 hooks the bottom end of the resisting piece 25, enabling the resisting piece 25 to jack up the support block 12, so that the clamping jaw 21 automatically unfolds to release the clamping, further saving the clamping time, reducing the working burden of the operator, and improving the testing efficiency.

[0052] In this embodiment, initially, the opposite first clamping plates 31 and second clamping plates 35 in each group are in a relatively separated state. Each first sliding pin 17 is located at the lowest point of the arc-shaped groove 15, so that each supporting block 12 is located at the highest position. At the same time, the clamping jaws 21 in each group are in an open state.

[0053] During use, the operator selects the silicon piezoresistive differential pressure sensor 14 to be tested, holds both ends of the silicon piezoresistive differential pressure sensor 14 with the index finger and thumb of one hand, and pulls up the wire connected to the silicon piezoresistive differential pressure sensor 14 with the other hand and places it on the V-shaped notch 13. At the same time, the operator applies a downward force on the supporting block 12, then the first sliding pin 17 slides along the track of the arc-shaped groove 15 and compresses the spring 19. When the first sliding pin 17 moves to the highest point of the arc-shaped groove 15, the supporting block 12 can no longer move downward, and the spring 19 stretches again, so that the supporting block 12 is kept at the lowest position. During the downward movement of the supporting block 12, the second sliding pin 23 slides in the second straight groove 24 and drives the clamping jaws 21 to close, so that the arc-shaped part at the top of the clamping jaws 21 presses on the outside of the silicon piezoresistive differential pressure sensor 14. Then the silicon piezoresistive differential pressure sensor 14 is supported by the V-shaped notch 13, clamped and pressed by the clamping jaws 21, so as to stably clamp and position the silicon piezoresistive differential pressure sensor 14, and accurately position the two ends of the silicon piezoresistive differential pressure sensor 14 with respect to the position of the cavity 32.

[0054] When the clamping jaws 21 are closed, the clamping arms 28 are closed synchronously, so that the wire clamping piece 29 can clamp and limit the wire of the silicon piezoresistive differential pressure sensor 14. The inclined extension part of the wire clamping piece 29 can guide and gather the wire towards the center during the process of clamping the wire, ensuring stable clamping and limiting of all the wires, and then facilitating the operator to distinguish the wires to connect the test system, reducing the work burden of the operator.

[0055] After the operator places and clamps all the multiple silicon piezoresistive differential pressure sensors 14 on the corresponding supporting blocks 12 in sequence, at this time, the ends of each silicon piezoresistive differential pressure sensor 14 accurately correspond to the position of the cavity 32. The operator simultaneously turns the two handwheels 39, so that the first lead screw 36 and the second lead screw 37 respectively drive the corresponding first clamping plates 31 and second clamping plates 35 to approach each other until the cavity 32 accurately sleeves on the outside of the silicon piezoresistive differential pressure sensor 14 and squeezes and clamps the two ends of the silicon piezoresistive differential pressure sensor 14. During this process, since the silicon piezoresistive differential pressure sensor 14 is clamped and restricted by the supporting block 12 and the clamping jaws 21, and the wire of the silicon piezoresistive differential pressure sensor 14 is simultaneously clamped by the wire clamping piece 29, the silicon piezoresistive differential pressure sensor 14 remains stable during this process, making the clamping process stable and accurate, and the operator does not need to repeatedly adjust the position of the silicon piezoresistive differential pressure sensor 14 to ensure its accurate clamping.

[0056] After the cavity 32 stably clamps both ends of the silicon piezoresistive differential pressure sensor 14, the sealing ring 34 can seal the gap between the cavity 32 and the end of the silicon piezoresistive differential pressure sensor 14. At this time, the operator connects the wires of each silicon piezoresistive differential pressure sensor 14 to the test system. Subsequently, high-pressure air and low-pressure air are respectively introduced into the two air pressure tubes 40, so that the two ends of the silicon piezoresistive differential pressure sensor 14 are respectively affected by high-pressure air and low-pressure air to generate electrical signals, and the test system is used to detect and compare whether the readings of the silicon piezoresistive differential pressure sensor 14 are accurate and whether the numerical fluctuations exceed the acceptable range.

[0057] When the support block 12 and the jaw 21 clamp the silicon piezoresistive differential pressure sensor 14, the support block 12 being at a low position causes the abutting piece 25 to be in an inclined state, and the bottom end of the abutting piece 25 remains in contact with the surface of the base 10. During the process of the first clamping plates 31 and 51 approaching each other to clamp both ends of the silicon piezoresistive differential pressure sensor 14, the toothed plate 26 moves together with the first clamping plate 31, so the tooth tip of the toothed plate 26 slides under the bottom side of the abutting piece 25. When the inclined surface of the tooth tip of the toothed plate 26 contacts the abutting piece 25, it will push the abutting piece 25 upward to make the abutting piece 25 flip until the tooth tip of the toothed plate 26 passes through the abutting piece 25, and the bottom end of the abutting piece 25 falls again to contact the surface of the base 10.

[0058] When the test is completed and the operator reversely rotates the handwheel 39 to drive the first clamping plate 31 and the second clamping plate 35 to move away from each other, the toothed plate 26 moves together with the first clamping plate 31 again. At this time, the tooth tip of the toothed plate 26 hooks the bottom end of the abutting piece 25 and applies a thrust to the abutting piece 25. Then the abutting piece 25 converts the horizontal thrust of the toothed plate 26 into an upward thrust on the support block 12, jacks up the support block 12 and at the same time drives the jaw 21 to open, so that the silicon piezoresistive differential pressure sensor 14 is naturally released from the clamped state. The operator can conveniently remove the tested silicon piezoresistive differential pressure sensor 14. At this time, the support block 12 returns to the initial state, and the jaw 21 also remains in the open state. The operator can place the silicon piezoresistive differential pressure sensor 14 to be tested into it again. The operation is convenient without redundant operations, greatly saving the operator's operation actions and improving the test efficiency.

[0059] When the support block 12 is at a high position, the abutting piece 25 naturally hangs down vertically. When the support block 12 is pressed down, the bottom end of the abutting piece 25 first contacts the inclined surface of the helical tooth block 27 and guides the abutting piece 25 to become inclined again, realizing the cycle of actions.

[0060] The above-mentioned first motor toothed plate 26, second motor wire clamping piece 29, conductive rail sealing ring 34, bearing first lead screw 36, and brush 42 are mature existing technologies and will not be elaborated in this article.

[0061] As used in the specification and claims, certain terms are used to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not distinguish components by the difference in names, but by the difference in functions of the components. As used throughout the specification and claims, the term "comprising" is an open-ended term and should be interpreted as "comprising but not limited to". "Substantially" means within an acceptable error range. Those skilled in the art can solve the technical problems within a certain error range and basically achieve the technical effects.

[0062] It should be noted that the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a commodity or system including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such commodity or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the commodity or system including the said element.

[0063] The above description shows and describes several preferred embodiments of the present application. However, as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the application concept described herein through the above teachings or the technology or knowledge in the relevant field. And any changes and variations made by those skilled in the art without departing from the spirit and scope of the present application shall fall within the protection scope of the appended claims of the present application.

Claims

1. A test fixture for a micro silicon piezoresistive differential pressure sensor, characterized in that: The test fixture for the micro silicon piezoresistive differential pressure sensor comprises: A base (10) and a silicon piezoresistive differential pressure sensor (14), wherein a slide groove (30) is provided on the surface of the base (10), a plurality of first clamping plates (31) and second clamping plates (35) are slidably connected in the slide groove (30), and the first clamping plates (31) and the second clamping plates (35) are arranged opposite to each other in pairs; A support (11), the base (10) being fixedly connected with the support (11) between each set of opposite first clamping plates (31) and second clamping plates (35), each of the supports (11) being slidably connected with a support block (12), the base (10) being fixedly connected with a group of clamping claw seats (22) at both sides of each support (11), each group of the clamping claw seats (22) being respectively hinged with two groups of clamping claws (21) arranged oppositely and used for clamping a silicon piezoresistive differential pressure sensor (14); A V-shaped notch (13) for supporting and placing a silicon piezoresistive differential pressure sensor (14) is provided on the top of each support block (12), and a group of oppositely arranged cavities (32) are fixedly connected at corresponding positions at both ends of the silicon piezoresistive differential pressure sensor (14) on each set of opposite first clamping plates (31) and second clamping plates (35).

2. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 1, characterized in that: Each of the support blocks (12) is provided with two symmetrical arc grooves (15); each of the support seats (11) is provided with a first straight groove (16) at the corresponding positions of each arc groove (15); each of the first straight grooves (16) is slidably connected with a first sliding pin (17) sliding in the corresponding arc groove (15); each of the first sliding pins (17) is fixedly connected with a group of sliding rods (18) at the two ends; each of the support seats (11) is fixedly connected with a sliding rod seat (20) at the corresponding positions of the sliding rod (18); each of the sliding rods (18) is slidably connected with the corresponding sliding rod seat (20); and a spring (19) surrounding the outer side of the sliding rod (18) is provided between each of the sliding rods (18) and the corresponding sliding rod seat (20).

3. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 2, characterized in that: A group of second straight grooves (24) is provided on each of the support blocks (12) below the arc groove (15), a second sliding pin (23) is slidably connected in each group of the second straight grooves (24), and both ends of each second sliding pin (23) are fixedly connected to the corresponding clamping claw (21).

4. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 1, characterized in that: The top of each clamping jaw (21) is provided with an arc-shaped portion for pressing the silicon piezoresistive differential pressure sensor (14), and the tops of the clamping jaws (21) respectively located on both sides of the support (11) are arranged alternately.

5. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 1, characterized in that: The top of each group of the clamping jaws (21) is respectively fixedly connected to a clamping arm (28) arranged oppositely, and the tops of the two clamping arms (28) arranged oppositely are respectively fixedly connected to a group of buckle wire pieces (29), and each buckle wire piece (29) is provided with a bent extension portion at both ends, and the extension portions of the two opposite buckle wire pieces (29) are arranged in a staggered manner with respect to each other.

6. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 1, characterized in that: The base (10) is provided with a first screw (36) and a second screw (37) at both sides of the slide groove (30), each of the first clamping plates (31) is threadedly connected to the second screw (37) and is slidably connected to the first screw (36), each of the second clamping plates (35) is threadedly connected to the first screw (36) and is slidably connected to the second screw (37), and two groups of screw seats (38) are fixedly connected at both ends of the first screw (36) and the second screw (37) on the base (10), and the two groups of screw seats (38) are rotatably connected to the first screw (36) and the second screw (37), respectively, and the ends of the first screw (36) and the second screw (37) extending out of the screw seats (38) are fixedly connected to hand wheels (39).

7. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 6, characterized in that: Each support block (12) is hingedly provided with a butt plate (25) at the bottom, and a group of beveled tooth blocks (27) are fixedly connected to the base (10) below each butt plate (25). A hook tooth plate (26) is slidably connected between each group of beveled tooth blocks (27) in the slide groove (30), and the tooth tip inclined surface of each hook tooth plate (26) is parallel to the beveled tooth block (27), and each hook tooth plate (26) is fixedly connected to the corresponding first clamping plate (31).

8. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 1, characterized in that: A second clamping plate (35) is fixedly connected to one end of each cavity (32) away from the silicon piezoresistive differential pressure sensor (14); each second clamping plate (35) is communicated with the interior of the corresponding cavity (32); and a group of sealing rings (34) are fixedly connected to the inner wall of one end of each cavity (32) close to the silicon piezoresistive differential pressure sensor (14).

9. A test fixture for a micro silicon piezoresistive differential pressure sensor according to claim 8, characterized in that: Two groups of pressure-resistant hoses (41) are fixedly connected to both sides of the base (10), and a pressure tube (40) is fixedly connected inside each group of the pressure-resistant hoses (41). High-pressure air and low-pressure air are introduced into the two pressure tubes (40) respectively. Two cavities (32) respectively located on the first clamping plate (31) and the second clamping plate (35) are connected to the two pressure tubes (40) through (42).

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