A test fixture for a miniature silicon piezoresistive differential pressure sensor

Abstract

The application belongs to the technical field of sensor detection, and specifically relates to a test fixture for a miniature silicon piezoresistive differential pressure sensor, which comprises a base, a plurality of first clamping plates and second clamping plates are slidably connected in a sliding groove on the surface of the base, a plurality of supports are fixedly connected to the base, 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 respectively hinged to each clamping jaw seat, a V-shaped notch for supporting and placing a silicon piezoresistive differential pressure sensor is formed in the top of each supporting block, and a set of oppositely arranged cavities are fixedly connected to each set of opposite first clamping plates and second clamping plates at positions corresponding to the two ends of the silicon piezoresistive differential pressure sensor. The clamping jaws are used for pre-clamping positioning, and the wire clamping piece is used for clamping and limiting the wires of the silicon piezoresistive differential pressure sensor, so that the problems of unstable placement, tilting and falling due to accidental touching, and the problems of the operator needing to pay attention and repeatedly adjusting are avoided.

Description

TECHNICAL FIELD

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

[0002] A differential pressure sensor is a device for measuring the pressure difference between two different positions and can convert the pressure difference value into an electrical signal output, and is widely used in the fields of industry, medicine, environmental monitoring, etc. With the progress and development of science and technology, differential pressure sensors are also developing towards miniaturization or micromation, and the structure of differential pressure sensors is more compact and the degree of integration is higher, so that the application scenarios of differential pressure sensors are also widened, such as portable medical devices, intelligent monitoring devices, new energy vehicle sensors, and pressure nodes in industrial Internet of Things.

[0003] Differential pressure sensors can be divided into piezoresistive differential pressure sensors, capacitive differential pressure sensors, resonant differential pressure sensors, and inductive differential pressure sensors according to their sensing principles. Among them, piezoresistive differential pressure sensors are widely used due to their high sensitivity, simple structure, easy miniaturization, and low production cost and processing difficulty, so their production is very large.

[0004] After the differential pressure sensor is processed and produced, it is usually necessary to sample and test the batch-produced differential pressure, test whether the reading value of the differential pressure sensor is accurate and whether the numerical fluctuation is beyond the acceptable range, and calculate the production yield of the differential pressure sensor according to the test results to feed back to the production workshop to optimize the production and processing technology.

[0005] The most traditional differential pressure sensor testing method generally adopts a pair of chamber clamping method for a single sensor. An operator places a single sensor to be detected in the test fixture, connects the lead wire of the differential pressure sensor with the detection system, and then drives the fixture to clamp and seal the high pressure end and the low pressure end of the sensor, respectively applies high pressure and low pressure conditions, to detect the sensor parameters and quality. However, this manual detection method one by one is troublesome and inefficient, and the single assembly fixture method cannot meet the production needs of batch testing, so a fixture capable of clamping and detecting multiple sensors at the same time is needed.

[0006] A test fixture for preparing a silicon capacitance differential pressure sensor is disclosed in Chinese Patent No. CN101424577B, which includes a horizontal, positioning, clamping, air path, sealing part, left chamber, six intermediate chambers, right chamber are placed in turn between the left support seat, right support seat, seven V-shaped supports are placed between each chamber, the guide rod passes through the chamber, V-shaped support, left support seat, right support seat guide rod hole and fixed; compression screw through the right support seat, the compression seat constitutes a clamping mechanism; this test fixture can clamp 7 sensors at a time, and simultaneously test, to meet the testing needs of batch production.

[0007] But for small or micro differential pressure sensor, the above patent will encounter the following problems:

[0008] 1. The micro sensor is small in size and light in weight, and is easily affected by personnel operation when initially placed, and is difficult to be stably placed on the V-shaped support. In the subsequent process of controlling the mutual approach of each chamber to clamp and seal the two ends of the differential pressure sensor, the above patent is difficult 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 repeatedly adjusted, time is wasted, which is contrary to the purpose of accelerating the clamping detection speed and improving the efficiency of batch testing.

[0009] 2. The micro sensor generally extends a lead wire, and since the sensor is small in size and light in weight, the weight of the lead wire accounts for a large proportion of the overall weight of the sensor. The above patent cannot clamp and limit the lead wire, so that the sensor body is easily affected by the weight of the lead wire and falls off or falls from the V-shaped support when placing the sensor, thereby causing the operator to pay more attention when placing, causing the operator to have a work burden, and the scattered lead wire is not convenient for the operator to operate, thereby affecting the detection. SUMMARY

[0010] The present application overcomes the deficiencies of the prior art and solves the technical problem by providing multiple sets of first clamping plates and second clamping plates, which can simultaneously clamp and test multiple silicon piezoresistive differential pressure sensors, thereby improving the testing efficiency and realizing timely and efficient feedback of silicon piezoresistive differential pressure sensor production. By providing clamping jaws, the silicon piezoresistive differential pressure sensor can be pre-clamped and positioned before final clamping with the support block. The position of the silicon piezoresistive differential pressure sensor is accurately positioned in the cavity, thereby ensuring that each silicon piezoresistive differential pressure sensor can accurately enter the cavity when simultaneously clamping and connecting the two ends of multiple silicon piezoresistive differential pressure sensors, ensuring the stability and accuracy of the clamping process. By providing clamping arms and wire clamps, the weight of the wires is avoided from causing the silicon piezoresistive differential pressure sensor to tilt and misalign with the cavity. The wire clamps clamp and restrict the wires, allowing multiple wires corresponding to each silicon piezoresistive differential pressure sensor to be bundled together, making it easier for the operator to distinguish between different wires corresponding to different silicon piezoresistive differential pressure sensors, and also allowing the operator to distinguish between the wires on the same silicon piezoresistive differential pressure sensor, making it easier for the operator to perform wiring operations. By connecting the support block and the clamping jaw through the second sliding pin and the second straight slot, the pre-clamping action is automatically completed while the silicon piezoresistive differential pressure sensor is placed. By using the stop plate and the hook tooth plate, the support block is automatically lifted upward and the clamping jaw is automatically opened while 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, realizing a fast and automatic unloading action. This greatly saves the operator's operation actions, saves clamping time, improves testing efficiency, and reduces the operator's work burden.

[0011] To achieve the above-mentioned purposes, the present application provides the following technical solutions: a test fixture for a miniature silicon piezoresistive differential pressure sensor, comprising:

[0012] a base, a silicon piezoresistive differential pressure sensor, the base is provided with a sliding groove on the surface, a plurality of first clamping plates and second clamping plates are slidably connected in the sliding groove, and the first clamping plates and the second clamping plates are arranged opposite to each other in pairs;

[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 on both sides of each support on the base, and two sets of opposite clamping jaws for clamping the silicon piezoresistive differential pressure sensor are respectively hinged on each clamping jaw seat;

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

[0015] Further, two arc-shaped grooves are formed on each support block, a first straight groove is formed at the position corresponding to each arc-shaped groove at the two ends of each support block, a first sliding pin slidingly connected in the corresponding arc-shaped groove is arranged in each first straight groove, a group of sliding rods are fixedly connected to the two ends of each first sliding pin, a sliding rod seat is fixedly connected to the position corresponding to the sliding rod at the two sides of each support block, each sliding rod is slidingly connected with the corresponding sliding rod seat, and a spring is arranged around the outer side of each sliding rod between the sliding rod and the corresponding sliding rod seat.

[0016] Further, a group of second straight grooves are formed on each support block below the arc-shaped grooves, a second sliding pin is slidingly connected in each group of second straight grooves, and the two ends of each second sliding pin are fixedly connected with the corresponding clamping jaw.

[0017] Further, an arc-shaped part for pressing the silicon piezoresistive differential pressure sensor is arranged at the top of each clamping jaw, and the top ends of the clamping jaws arranged at the two sides of the support block are staggered with each other.

[0018] Further, a pair of clamping arms are fixedly connected to the top of each group of clamping jaws, a group of buckling pieces are fixedly connected to the top of each pair of clamping arms, a bent extension is arranged at the two ends of each buckling piece, and the extensions of the two buckling pieces are arranged in a staggered manner.

[0019] Further, a first lead screw and a second lead screw are arranged on the base at the two sides of the sliding groove, each second clamping plate is threadedly connected with the first lead screw and slidingly connected with the second lead screw, each second clamping plate is threadedly connected with the first lead screw and slidingly connected with the second lead screw, two groups of lead screw seats are fixedly connected to the base at the two ends of the first lead screw and the second lead screw, the two groups of lead screw seats are rotationally connected with the first lead screw and the second lead screw, and the end portions of the first lead screw and the second lead screw extending out of the lead screw seats are fixedly connected with hand wheels.

[0020] Further, a resisting piece is arranged at the bottom of each support block, a group of bevel tooth blocks are fixedly connected to the base below each resisting piece, a hook tooth plate is slidingly connected in the sliding groove between each group of bevel tooth blocks, the tooth tip inclined surface of each hook tooth plate is parallel to the bevel tooth block, and each hook tooth plate is fixedly connected with the corresponding first clamping plate.

[0021] Further, a second clamping plate is fixedly connected to the end of each cavity away from the silicon piezoresistive differential pressure sensor, each second clamping plate is in communication with the inside of the corresponding cavity, and a group of sealing rings are fixedly connected to the inner wall of the end of each cavity close to the silicon piezoresistive differential pressure sensor.

[0022] Further, two groups of pressure-resistant hoses are fixedly connected on both sides of the base, and an air pressure pipe is fixedly connected in each group of the pressure-resistant hoses, two air pressure pipes are connected with high-pressure air and low-pressure air respectively, and two cavities on the first clamping plate and the second clamping plate are connected with the two air pressure pipes through communication.

[0023] In summary, compared with the prior art, the beneficial effects of the present application are that:

[0024] (1) By arranging multiple groups of first clamping plates and second clamping plates, multiple silicon piezoresistive differential pressure sensors can be clamped and tested at the same time, thereby improving the testing efficiency and realizing timely and efficient feedback of silicon piezoresistive differential pressure sensor production.

[0025] (2) By arranging the clamping jaws, the silicon piezoresistive differential pressure sensors can be pre-clamped and positioned before final clamping with the support blocks, and the positions of the silicon piezoresistive differential pressure sensors and the cavities are accurately positioned, thereby ensuring that each silicon piezoresistive differential pressure sensor can accurately enter the cavity when multiple silicon piezoresistive differential pressure sensors are simultaneously clamped and connected at both ends, and the stability and accuracy of the clamping process are ensured.

[0026] (3) By arranging the clamping arms and the wire clamping pieces, the weight of the wires is avoided from causing the silicon piezoresistive differential pressure sensors to be skewed, so that the silicon piezoresistive differential pressure sensors cannot be aligned with the cavities, and the wire clamping pieces clamp and limit the wires, so that multiple wires corresponding to each silicon piezoresistive differential pressure sensor are bundled together, which facilitates the operator to distinguish the wires corresponding to different silicon piezoresistive differential pressure sensors, and also facilitates the operator to distinguish the wires on the same silicon piezoresistive differential pressure sensor, thereby facilitating the operator to perform wiring operations.

[0027] (4) By connecting the support blocks and the clamping jaws through the second sliding pins and the second straight grooves, the pre-clamping action is automatically completed while the silicon piezoresistive differential pressure sensors are placed, and by using the abutting pieces and the hook teeth plates, the support blocks are automatically lifted upward and the clamping jaws are automatically opened 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 sensors, thereby realizing rapid and automatic unloading action, which greatly saves the operation actions of the operator, saves the clamping time, improves the testing efficiency, and reduces the work burden of the operator. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a perspective view of the present patent.

[0029] Figure 2 It is a top view of the present patent.

[0030] Figure 3 It is Figure 2 It is a perspective view of A-A.

[0031] Figure 4 It isFigure 3 Enlarged view of the portion B.

[0032] Figure 5 Structure diagram of the main mechanism of the patent.

[0033] Figure 6 For Figure 5 Enlarged view of the portion C.

[0034] Figure 7 Structure diagram of the mechanism when the clamping jaw is closed.

[0035] Figure 8 Structure diagram of the mechanism when the clamping jaw is opened.

[0036] Figure 9 Structure diagram of the mechanism of the support and the supporting block.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS: base 10; support 11; supporting block 12; V-shaped notch 13; silicon piezoresistance differential pressure sensor 14; arc-shaped groove 15; first straight groove 16; first sliding pin 17; sliding rod 18; spring 19; sliding rod seat 20; clamping jaw 21; clamping jaw seat 22; second sliding pin 23; second straight groove 24; abutting piece 25; hook-toothed plate 26; bevel-toothed block 27; clamping arm 28; clamping line piece 29; sliding 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; hand wheel 39; air pressure pipe 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 DESCRIPTION

[0038] In order to make the personnel in the technical field better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application.

[0039] As Figures 1-9As shown, a micro-silicon piezoresistive differential pressure sensor test fixture includes a base 10, a sliding groove 30 is formed on the base 10, a plurality of first clamping plates 31 and second clamping plates 35 are respectively slidably connected in the sliding groove 30, the first clamping plates 31 and the second clamping plates 35 are staggered and arranged opposite to each other, each first clamping plate 31 and the opposite second clamping plate 35 are fixedly connected with a cavity 32 arranged opposite to each other and respectively connected with high-pressure air and low-pressure air, a support 11 is fixedly connected between each set of opposite first clamping plate 31 and second clamping plate 35 on the base 10, a support block 12 is slidably connected in the support 11, a V-shaped notch 13 is formed on the top of the support block 12, a silicon piezoresistive differential pressure sensor 14 is placed on each V-shaped notch 13, each cavity 32 corresponds to the position of 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 with a second clamping plate 35, each second clamping plate 35 is in communication with the corresponding cavity 32, a set 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 sets of pressure-resistant hoses 41 are respectively fixedly connected on both sides of the base 10, a pressure tube 40 is fixedly connected in each set of pressure-resistant hose 41, two pressure tubes 40 are respectively connected with high-pressure air and low-pressure air, and two cavities 32 respectively located on the first clamping plate 31 and the second clamping plate 35 are connected through 42 between the two pressure tubes 40.

[0040] By setting 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 can be applied respectively, so that the silicon piezoresistive differential pressure sensor 14 can be clamped and tested for whether the reading value is accurate, whether the numerical fluctuation exceeds the acceptable range and other parameters, to facilitate the estimation of the yield rate and feedback adjustment and optimization of the production process.

[0041] As shown, Figures 1-9 A clamping jaw seat 22 is fixedly connected on both sides of the support 11 on the base 10, a set of clamping jaws 21 are hingedly connected on each clamping jaw seat 22, the two sets of clamping jaws 21 located on both sides of the support 11 are arranged opposite to each other and staggered with each other, and an arc-shaped part covering the silicon piezoresistive differential pressure sensor 14 is arranged on the top of each set of clamping jaws 21.

[0042] By setting the clamping jaw 21, the silicon piezoresistive differential pressure sensor 14 can be fully clamped and covered by cooperating with the support block 12, so that when the operator places a plurality of silicon piezoresistive differential pressure sensors 14 in turn, the silicon piezoresistive differential pressure sensor 14 can be pre-positioned, ensuring that the two ends of the silicon piezoresistive differential pressure sensor 14 correspond accurately with the cavities 32, facilitating the subsequent close approach of the first clamping plate 31 and the second clamping plate 35 to seal and clamp the end of the silicon piezoresistive differential pressure sensor 14.

[0043] As shown, Figures 1-9As shown, two arc-shaped grooves 15 are formed on each support block 12, and a first straight groove 16 is formed at the corresponding position of each arc-shaped groove 15 at the two ends of each support 11. 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 is fixedly connected to the two ends of each first sliding pin 17. A sliding rod seat 20 is fixedly connected to the corresponding position of each sliding rod 18 at the two sides of each support 11. Each sliding rod 18 is slidably connected to the corresponding sliding rod seat 20. A spring 19 that surrounds the outer side of the sliding rod 18 is arranged between each sliding rod 18 and the corresponding sliding rod seat 20. A set of second straight grooves 24 is formed below the arc-shaped groove 15 on each support block 12. A second sliding pin 23 is slidably connected in each set of second straight grooves 24. The two ends of each second sliding pin 23 are fixedly connected to the corresponding clamping jaw 21.

[0044] By arranging the arc-shaped groove 15 and the first sliding pin 17, the support block 12 can be positioned at two high and low positions and maintain its state by the elasticity of the spring 19. By arranging the second sliding pin 23 and the second straight groove 24, the clamping jaw 21 naturally opens when the support block 12 is at a high position, and the clamping jaw 21 closes each other to clamp the silicon piezoresistive differential pressure sensor 14 when the support block 12 is at a low position. Therefore, the operator can press the support block 12 to make the clamping jaw 21 automatically clamp and fix the silicon piezoresistive differential pressure sensor 14 when placing the silicon piezoresistive differential pressure sensor 14, without unnecessary steps, simple operation, saving clamping time to improve test efficiency.

[0045] Moreover, the stability of the silicon piezoresistive differential pressure sensor 14 is maintained by the cooperation of the clamping jaw 21 and the support block 12, avoiding the silicon piezoresistive differential pressure sensor 14 from falling due to unnecessary collision, thereby ensuring the stability and accuracy of the subsequent process of the cavity 32 being sleeved on the end of the silicon piezoresistive differential pressure sensor 14, without the need for the operator to repeatedly adjust, thereby reducing the work burden and operation difficulty of the operator.

[0046] As shown in Figures 1-9 Each set of clamping jaws 21 is fixedly connected with a pair of clamping arms 28 arranged oppositely at the top, and a set of buckling pieces 29 is fixedly connected to the top of the two oppositely arranged clamping arms 28. Each buckling piece 29 is provided with a bent extension at the two ends, and the extensions of the two oppositely arranged buckling pieces 29 are arranged oppositely.

[0047] The clamping arm 28 and the wire clamping piece 29 are arranged to clamp and fix the body of the silicon piezoresistance differential pressure sensor 14, and the wire clamping piece 29 is arranged to clamp and limit the wires of the silicon piezoresistance differential pressure sensor 14, so that the weight of the wires does not cause the silicon piezoresistance differential pressure sensor 14 to be tilted and the silicon piezoresistance differential pressure sensor 14 to be misaligned with the cavity 32, and the wire clamping piece 29 clamping and limiting the wires can make the multiple wires corresponding to each silicon piezoresistance differential pressure sensor 14 be bundled together, so that the operator can distinguish the wires corresponding to different silicon piezoresistance differential pressure sensors 14, and can also distinguish the wires on the same silicon piezoresistance differential pressure sensor 14, so as to facilitate the operator to perform the wiring operation.

[0048] As shown in Figures 1-9 The first lead screw 36 and the second lead screw 37 are arranged on the base 10 at both sides of the sliding groove 30, each first clamping plate 31 is threadedly connected with the second lead screw 37 and is slidingly connected with the first lead screw 36, each second clamping plate 35 is threadedly connected with the first lead screw 36 and is slidingly connected with the second lead screw 37, and two groups of lead screw seats 38 are fixedly connected to the base 10 at both ends of the first lead screw 36 and the second lead screw 37, respectively, and are rotatably connected with the first lead screw 36 and the second lead screw 37, respectively, and 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 hand wheels 39.

[0049] The first lead screw 36 and the second lead screw 37 can be arranged to control the first clamping plate 31 and the second clamping plate 35 to move close to or away from each other, so as to realize the function of the cavity 32 being sleeved on the end of the silicon piezoresistance differential pressure sensor 14 to realize clamping and sealing, and one first lead screw 36 and one second lead screw 37 can be arranged to simultaneously drive multiple groups of first clamping plates 31 and second clamping plates 35 to move oppositely, so as to simplify the driving structure and reduce the production cost of the clamp.

[0050] As shown in Figures 1-9 Each support block 12 is hingedly connected with a pressing piece 25 at the bottom, a group of bevel tooth blocks 27 are fixedly connected to the base 10 below each pressing piece 25, and a hook tooth plate 26 is slidingly connected between each group of bevel tooth blocks 27 in the sliding groove 30, the tooth tip inclined surface of each hook tooth plate 26 is parallel to the bevel tooth block 27, and each hook tooth plate 26 is fixedly connected with the corresponding first clamping plate 31.

[0051] The pressing piece 25 and the hook tooth plate 26 are arranged, after detection is completed, the first clamping plate 31 and the second clamping plate 35 are moved away from each other, the hook tooth plate 26 hooks the bottom end of the pressing piece 25, the pressing piece 25 lifts the support block 12 upward, so that the clamping jaw 21 is automatically unfolded and removed, the clamping time is further saved, the work burden of the operator is reduced, and the test efficiency is improved.

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

[0053] In use, the operator selects the silicon piezoresistive differential pressure sensor 14 to be tested, holds the two ends of the silicon piezoresistive differential pressure sensor 14 with the index finger and the thumb of one hand, and holds the lead wire connected to the silicon piezoresistive differential pressure sensor 14 with the other hand, and places the lead wire on the V-shaped notch 13, and at the same time, the operator presses down the support block 12, so that the first sliding pin 17 slides along the track of the arc-shaped groove 15 and compresses the spring 19, and when the first sliding pin 17 moves to the highest point of the arc-shaped groove 15, the support block 12 cannot be lowered any more, and the spring 19 expands again, so that the support block 12 remains at the lowest position, and in the process of lowering the support block 12, the second sliding pin 23 slides in the second straight groove 24 and drives the clamping jaw 21 to close, so that the arc-shaped part at the top of the clamping jaw 21 covers the outside of the silicon piezoresistive differential pressure sensor 14, and the silicon piezoresistive differential pressure sensor 14 is supported by the V-shaped notch 13, clamped and covered by the clamping jaw 21, so that the silicon piezoresistive differential pressure sensor 14 is stably clamped and positioned, and the two ends of the silicon piezoresistive differential pressure sensor 14 are accurately positioned with the position of the cavity 32.

[0054] At the same time that the clamping jaw 21 is closed, the clamping arm 28 is synchronously closed, so that the wire clamping piece 29 can clamp and limit the lead wire of the silicon piezoresistive differential pressure sensor 14, and the inclined extension part of the wire clamping piece 29 can guide and gather the lead wire to the center during clamping the lead wire, so as to ensure that all the lead wires are stably clamped and limited, thereby facilitating the operator to distinguish the lead wires to connect the lead wires to the test system and reducing the work burden of the operator.

[0055] After the operator places a plurality of silicon piezoresistive differential pressure sensors 14 on the corresponding support blocks 12 one by one and clamps them, at this time, the end of each silicon piezoresistive differential pressure sensor 14 accurately corresponds to the position of the cavity 32, and the operator simultaneously rotates the two hand wheels 39, so that the first and second lead screws 36 and 37 respectively drive the first and second clamping plates 31 and 35 to move closer to each other, until the cavity 32 is accurately sleeved outside the silicon piezoresistive differential pressure sensor 14 and presses and clamps the two ends of the silicon piezoresistive differential pressure sensor 14, and in this process, since the silicon piezoresistive differential pressure sensor 14 is clamped and limited by the support block 12 and the clamping jaw 21, and the lead wire of the silicon piezoresistive differential pressure sensor 14 is clamped by the wire clamping piece 29 at the same time, the silicon piezoresistive differential pressure sensor 14 always remains stable during this process, so that the clamping process is stable and accurate, and the operator does not need to repeatedly adjust the position of the silicon piezoresistive differential pressure sensor 14 to ensure accurate clamping.

[0056] After the silicon piezoresistive differential pressure sensor 14 is clamped by the support block 12 and the clamping jaw 21, 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 lead wires of each silicon piezoresistive differential pressure sensor 14 to the test system, and then high-pressure air and low-pressure air are respectively introduced into the two air pressure pipes 40, so that the silicon piezoresistive differential pressure sensor 14 generates an electrical signal under the action of high-pressure air and low-pressure air at both ends. The test system detects and compares whether the reading of the silicon piezoresistive differential pressure sensor 14 is accurate and whether the numerical fluctuation is within an acceptable range.

[0057] When the support block 12 clamps the silicon piezoresistive differential pressure sensor 14 with the clamping jaw 21, the support block 12 is at a low position, so that the abutting piece 25 is in an inclined state and the bottom end of the abutting piece 25 is in contact with the surface of the base 10. During the process of the first clamping plate 31 and the second clamping plate 51 moving close to each other to clamp both ends of the silicon piezoresistive differential pressure sensor 14, the hook tooth plate 26 moves with the first clamping plate 31, so that the tooth tip of the hook tooth plate 26 slides from the bottom side of the abutting piece 25. When the inclined surface of the tooth tip of the hook tooth plate 26 contacts the abutting piece 25, the abutting piece 25 is lifted upward to be flipped until the tooth tip of the hook tooth plate 26 passes through the abutting piece 25, and the bottom end of the abutting piece 25 falls again to be in contact with the surface of the base 10.

[0058] When the test is completed, the operator reversely rotates the hand wheel 39 to drive the first clamping plate 31 and the second clamping plate 35 to move away from each other, and the hook tooth plate 26 moves again with the first clamping plate 31. At this time, the tooth tip of the hook tooth plate 26 hooks the bottom end of the abutting piece 25 and applies a pushing force to the abutting piece 25. The abutting piece 25 converts the horizontal pushing force of the hook tooth plate 26 into an upward pushing force to the support block 12, lifts the support block 12 upward and drives the clamping jaw 21 to open. The silicon piezoresistive differential pressure sensor 14 is naturally released from the clamped state, and the operator can conveniently take out the tested silicon piezoresistive differential pressure sensor 14. At this time, the support block 12 returns to the initial state, and the clamping jaw 21 also remains in the expanded state. The operator can place the silicon piezoresistive differential pressure sensor 14 to be tested again, which is convenient and does not require additional operations, greatly saving the operation of the operator and improving the test efficiency.

[0059] When the support block 12 is at a high position, the abutting piece 25 naturally falls to be vertical. When the support block 12 is pressed down and moves, the bottom end of the abutting piece 25 first contacts the inclined surface of the inclined tooth block 27 and guides the abutting piece 25 to be inclined again, realizing the cycle of the action.

[0060] The first motor hook tooth plate 26, the second motor wire clamping piece 29, the conductive rail sealing ring 34, the bearing first lead screw 36, and the brush 42 are mature existing technologies, and will not be described herein.

[0061] As used in the specification and claims, certain terms have particular meanings. Those of skill in the art will understand that one or more embodiments described herein can be implemented without those terms. As used in the specification and claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. "Approximately" refers to within 10% of the indicated value.

[0062] It should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. "Approximately" refers to within 10% of the indicated value.

[0063] The foregoing description illustrates and describes several preferred embodiments of the present application. However, it is to be understood that the application is not limited to the precise embodiments described herein and that various modifications and changes can be effected therein by those skilled in the art without departing from the spirit of the application. It is intended that the description be considered as illustrative only and that the scope of the application is to be limited only by the appended claims.

Claims

1. A test fixture for a miniature silicon piezoresistive differential pressure sensor, characterized by, The micro silicon piezoresistive differential pressure sensor test fixture comprises: A base (10) is provided with a sliding groove (30) on the surface, a plurality of first clamping plates (31) and second clamping plates (35) are slidably connected in the sliding groove (30), and the first clamping plates (31) and the second clamping plates (35) are oppositely arranged in pairs; A support (11) is fixedly connected between each pair of oppositely arranged first clamping plates (31) and second clamping plates (35) on the base (10), a support block (12) is slidably connected in each support (11), a group of clamping jaw seats (22) are fixedly connected on both sides of each support (11) on the base (10), and two groups of oppositely arranged clamping jaws (21) for clamping the silicon piezoresistive differential pressure sensor (14) are hingedly connected on each group of clamping jaw seats (22); A V-shaped notch (13) for supporting the silicon piezoresistive differential pressure sensor (14) is formed at the top of each support block (12), and a group of oppositely arranged cavities (32) are fixedly connected on each pair of oppositely arranged first clamping plates (31) and second clamping plates (35) at positions corresponding to the two ends of the silicon piezoresistive differential pressure sensor (14); Two mutually symmetrical arc-shaped grooves (15) are formed on each support block (12), a first straight groove (16) is formed at a position corresponding to each arc-shaped groove (15) at the two ends of each support (11), a first sliding pin (17) that slides in the corresponding arc-shaped groove (15) is slidably connected in each first straight groove (16), a group of sliding rods (18) are fixedly connected at the two ends of each first sliding pin (17), a sliding rod seat (20) is fixedly connected at a position corresponding to the sliding rod (18) on each side of each support (11), each sliding rod (18) is slidably connected with the corresponding sliding rod seat (20), and a spring (19) is arranged between each sliding rod (18) and the corresponding sliding rod seat (20) and surrounds the outside of the sliding rod (18); A first lead screw (36) and a second lead screw (37) are arranged on both sides of the sliding groove (30) on the base (10), each first clamping plate (31) is threadedly connected with the second lead screw (37) and slidably connected with the first lead screw (36), each second clamping plate (35) is threadedly connected with the first lead screw (36) and slidably connected with the second lead screw (37), two groups of lead screw seats (38) are fixedly connected at the two ends of the first lead screw (36) and the second lead screw (37) on the base (10), the two groups of lead screw seats (38) are rotatably connected with the first lead screw (36) and the second lead screw (37), respectively, and the ends of the first lead screw (36) and the second lead screw (37) that protrude out of the lead screw seats (38) are fixedly connected with hand wheels (39). Two groups of pressure-resistant hoses (41) are fixedly connected to the two sides of the base (10), a gas pressure pipe (40) is fixedly connected in each group of pressure-resistant hoses (41), two gas pressure pipes (40) are connected to high-pressure air and low-pressure air respectively, and two cavities (32) on the first clamping plate (31) and the second clamping plate (35) are connected in communication with the two gas pressure pipes (40) through (42).

2. The test fixture for a micro-silicon piezoresistive differential pressure sensor according to claim 1, wherein A group of second straight grooves (24) are formed below the arc-shaped grooves (15) on each support block (12), a second sliding pin (23) is slidably connected in each group of second straight grooves (24), and the two ends of each second sliding pin (23) are fixedly connected with the corresponding clamping jaw (21).

3. The test fixture of claim 1, wherein, An arc-shaped part for pressing the silicon piezoresistive differential pressure sensor (14) is arranged on the top of each clamping jaw (21), and the top ends of the clamping jaws (21) on the two sides of the support (11) are staggered.

4. The test fixture of claim 1, wherein, Opposite clamping arms (28) are fixedly connected to the top of each group of clamping jaws (21), a group of buckling pieces (29) are fixedly connected to the top of the two opposite clamping arms (28), and the two ends of each buckling piece (29) are provided with bent extension parts, and the extension parts of the two opposite buckling pieces (29) are arranged in a staggered manner.

5. The test fixture of claim 1, wherein, A resisting piece (25) is hingedly connected to the bottom of each support block (12), a group of bevel tooth blocks (27) are fixedly connected below each resisting piece (25) on the base (10), a hook tooth plate (26) is slidably connected between each group of bevel tooth blocks (27) in the sliding groove (30), the tooth tip inclined surface of each hook tooth plate (26) is parallel to the bevel tooth block (27), and each hook tooth plate (26) is fixedly connected with the corresponding first clamping plate (31).

6. The test fixture of claim 1, wherein, A second clamping plate (35) is fixedly connected to the end of each cavity (32) away from the silicon piezoresistive differential pressure sensor (14), each second clamping plate (35) is in communication with the inside of the corresponding cavity (32), and a group of sealing rings (34) are fixedly connected to the inner wall of the end of each cavity (32) close to the silicon piezoresistive differential pressure sensor (14).

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