Air tight test fixture

Abstract

The utility model discloses airtight test fixture, specifically at test fixture technical field, including jig main part, be provided with test subassembly on the jig main part, test subassembly includes the clamping plate of setting in the one side of jig main part top, is provided with the test substrate between the clamping plate and jig main part, is provided with a plurality of staggered mouth for module placement on the test substrate and is passed through, the utility model discloses a jig main part and the detection needle of pressure resistance of adopting insulation pressure resistance, collocation low impedance test pin, solved the problem that the conventional equipment cannot directly dock IGBT module high voltage, large current characteristic, avoid test arc or contact badly, and through the elastic contact structure and the positioning pin limit design of the aid elastic resistance to contact rib, ensure that detection needle and module terminal alignment accurate, reduce contact resistance interference, solved the problem that the parasitic parameter influence test data accuracy.

Description

Technical Field

[0001] This utility model relates to the field of testing fixture technology, and more specifically, to an airtightness testing fixture. Background Technology

[0002] IGBT (Insulated Gate Bipolar Transistor) power modules, as core components of power electronic devices, are widely used in key fields such as new energy vehicles, rail transportation, smart grids, and industrial frequency conversion due to their high frequency, high power density, and wide voltage adaptability. Essentially, they integrate core components such as IGBT chips, freewheeling diode chips, drive circuits, electrode terminals, and heat dissipation substrates into a single integrated housing through precision packaging technology, forming a standardized functional unit that can be directly installed. Their performance stability directly determines the operational reliability and service life of downstream equipment. To ensure the factory quality and operational safety of IGBT power modules, it is necessary to comprehensively verify their electrical performance (such as saturation voltage drop, leakage current, and switching characteristics), functional integrity, and hermeticity using a dedicated test fixture. However, the material properties and structural design of conventional test fixtures cannot be adapted to the high-voltage and high-current characteristics of IGBT power modules. Insufficient insulation withstand voltage of the fixture body and excessively high impedance of the test pins can lead to safety hazards such as arcing and poor contact during testing, making it impossible to achieve stable electrical connection and parameter detection. Therefore, a hermeticity test fixture is provided. Utility Model Content

[0003] In order to overcome the above-mentioned defects of the prior art, the present invention provides an airtightness testing fixture, which aims to solve the problems mentioned in the background art.

[0004] This utility model provides the following technical solution: an airtightness testing fixture, including a fixture body, on which a testing component is provided; The test assembly includes a clamp plate disposed on one side of the top of the fixture body, a test base plate disposed between the clamp plate and the fixture body, and a plurality of misalignment openings for module placement are provided through the test base plate, and a plurality of mounting blocks are respectively disposed on the top of the inner wall of each misalignment opening, and test pins are embedded in the plurality of mounting blocks. One end of the test pin is provided with a detection pin, and the other end of the test pin is provided with an elastic abutment rib.

[0005] Optionally, in a possible implementation, the clamp plate is provided with a plurality of first clearance openings, and the top of the fixture body is provided with a plurality of second clearance openings, and each of the first clearance openings is connected to the corresponding second clearance opening. Optionally, in a possible implementation, mounting grooves are respectively provided on both sides of the top of the fixture body, and elastic abutment blocks are respectively provided at both ends of the test substrate. The two elastic abutment blocks extend into the corresponding mounting grooves and engage with the mounting grooves. A limiting hole is provided through one side of the inner wall of the mounting groove. A support shaft is inserted into the bottom of the clamping plate. One end of the support shaft is fixed to the fixture body, and several threaded holes are provided through the clamping plate. The technical effects and advantages of this utility model are as follows: By using an insulated and voltage-resistant fixture body and a voltage-resistant test probe, along with low-impedance test pins, the problem that conventional equipment cannot directly connect to the high voltage and high current characteristics of IGBT modules is solved, avoiding arcing or poor contact during testing. By utilizing the elastic contact structure of the elastic abutment ribs and the positioning pin limit design, the alignment of the test probe and the module terminal is ensured to be accurate, reducing contact resistance interference and solving the problem of parasitic parameters affecting the accuracy of test data. Attached Figure Description

[0006] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of this disclosure.

[0007] Figure 1 This is a front view of the overall structure of this utility model.

[0008] Figure 2 This is a side view of the overall structure of this utility model.

[0009] Figure 3 This is an exploded view of the overall structure of this utility model.

[0010] Figure 4 This is a schematic diagram of the detection needle, test pin, elastic contact rib, test substrate, mounting block and elastic contact block of this utility model.

[0011] The attached figures are labeled as follows: 1. Fixture body; 2. Clamping plate; 3. Test base plate; 4. Misalignment opening; 5. Mounting block; 6. Test pin; 7. Detection pin; 8. Elastic abutment rib; 9. First clearance opening; 10. Second clearance opening; 11. Mounting groove; 12. Elastic abutment block; 13. Support shaft. Detailed Implementation

[0012] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0013] This embodiment discloses a hermetic testing fixture for IGBT power modules, which aims to solve the problems in the prior art where conventional testing equipment cannot be adapted to the high voltage and high current characteristics of IGBT power modules, poor contact during testing, parasitic parameters interfering with test accuracy, and lack of targeted protective structures, so as to achieve accurate and efficient testing of the hermeticity and related electrical performance of IGBT power modules.

[0014] Specifically, the airtightness testing fixture includes a fixture body 1, which is made of epoxy resin fiberglass board and can be adapted to the insulation requirements of high voltage testing scenarios. The fixture body 1 is equipped with an integrated testing component to realize the integrated functions of module positioning, electrical connection and airtightness testing.

[0015] The test assembly includes a clamping plate 2 located on one side of the top of the fixture body 1, with a support shaft 13 inserted into its bottom. The end of the support shaft 13 is fixed to the fixture body 1 by threads, and the clamping plate 2 has several threaded holes through it. The clamping plate 2 and the fixture body 1 can be fastened and locked together by bolts to ensure stable clamping of the module during the test.

[0016] A test substrate 3 is provided between the clamping plate 2 and the fixture body 1. The test substrate 3 is made of alumina ceramic substrate, which has both high insulation and low thermal resistance characteristics. Several misalignment ports 4 for placing IGBT modules are opened through the test substrate 3. The size of the misalignment ports 4 is adapted to the package size of commonly used IGBT modules. Several mounting blocks 5 are provided on the top of the inner wall of each misalignment port 4. They are fixed to the test substrate 3 by high temperature sintering. Test pins 6 are embedded in each of the mounting blocks 5.

[0017] One end of the test pin 6 is soldered with a test pin 7, model P75-B1, which can accurately connect to the gate (G), emitter (E), and collector (C) terminals of the IGBT module; the other end of the test pin 6 has an integrally formed elastic contact rib 8, which is made of beryllium bronze and can fit tightly with the wiring terminals of external test instruments through elastic contact, avoiding excessive contact resistance from affecting test accuracy. The connection between the rib 8 and the test pin 6 adopts a rounded transition design, which can withstand insertion and removal without fatigue damage.

[0018] The clamping plate 2 has several first clearance openings 9 through it, and the top of the fixture body 1 has several second clearance openings 10. Each first clearance opening 9 is connected to the corresponding second clearance opening 10, which can provide clearance space for the heat dissipation boss of the IGBT module and external wiring, and avoid mechanical interference.

[0019] The top two sides of the fixture body 1 are respectively provided with mounting grooves 11. The two ends of the test substrate 3 are respectively integrally formed with elastic abutment blocks 12 by injection molding. The two elastic abutment blocks 12 extend into the corresponding mounting grooves 11 and are engaged with the mounting grooves 11. A limiting hole is opened through one side of the inner wall of the mounting groove 11. The diameter of the limiting hole can be inserted into the positioning pin to realize the anti-displacement fixation of the test substrate 3, and ensure the alignment accuracy between the detection pin 7 and the module terminal during the test. The specific working principle is as follows: the IGBT module to be tested is placed into the misalignment slot 4 of the test substrate 3, ensuring that the electrode terminals of the module face upward; the test substrate 3 is fixed on the fixture body 1 by the cooperation of the elastic contact block 12 and the mounting groove 11, and the positioning pin is inserted to complete the limit.

[0020] Press the clamp 2 downward along the support shaft 13 so that the detection needle 7 makes precise contact with the gate, emitter and collector terminals of the IGBT module. Lock the clamp 2 to the fixture body 1 with bolts. At this time, the elastic contact rib 8 undergoes elastic deformation due to pressure and fits tightly with the wiring terminals of external testing instruments such as power analyzers.

[0021] Test pin 6 inputs a 15V drive voltage to the gate of the IGBT module. At the same time, the collector-emitter saturation voltage drop and leakage current are collected through the detection pin 7. The data is transmitted to the power analyzer through the test pin to realize static parameter detection. The low parasitic inductance design of test pin 6 can avoid interference with the switching waveform and ensure the detection accuracy of dynamic parameters such as turn-on time and turn-off time.

[0022] Loosen the clamp fixing bolts, remove the test substrate 3 and IGBT module, and the elastic contact rib 8 returns to its initial state, completing a single test process.

[0023] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. An airtightness testing fixture, comprising a fixture body (1), characterized in that: The fixture body (1) is provided with a test component; The test assembly includes a clamping plate (2) disposed on one side of the top of the fixture body (1), a test substrate (3) disposed between the clamping plate (2) and the fixture body (1), a plurality of misaligned openings (4) for placing modules are provided through the test substrate (3), and a plurality of mounting blocks (5) are respectively disposed on the top of the inner wall of each misaligned opening (4), and test pins (6) are embedded in each of the mounting blocks (5). One end of the test pin (6) is provided with a detection pin (7), and the other end of the test pin (6) is provided with an elastic abutment rib (8).

2. The airtightness testing fixture according to claim 1, characterized in that: The clamping plate (2) has several first clearance openings (9) through it, and the top of the fixture body (1) has several second clearance openings (10), and each of the first clearance openings (9) is connected to the corresponding second clearance opening (10).

3. The airtightness testing fixture according to claim 1, characterized in that: The fixture body (1) has mounting grooves (11) on both sides of its top, and the test substrate (3) has elastic abutment blocks (12) at both ends.

4. The airtightness testing fixture according to claim 2, characterized in that: The two elastic abutment blocks (12) extend into the corresponding mounting grooves (11) and engage with the mounting grooves (11), and a limit hole is provided through one side of the inner wall of the mounting groove (11).

5. The airtightness testing fixture according to claim 1, characterized in that: A support shaft (13) is inserted into the bottom of the clamping plate (2). One end of the support shaft (13) is fixed to the fixture body (1), and several threaded holes are opened through the clamping plate (2).

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