Rack heating plate air tightness test tooling and system

Abstract

The utility model discloses a kind of machine table heating plate air tightness test tool and system.The test tool includes base, test cavity and sealing cover body;Test cavity is set on base, sealing cover body and test cavity are measured piece clamped between the two;Wherein, positioning column is provided on base, for positioning the position of measured piece;Test cavity is cavity structure, including bottom and side wall;Through the connecting port of connecting helium mass spectrometer leak detector that cavity inside and outside is set on side wall, the top of side wall and the contact position of measured piece are provided with sealing ring;Sealing cover body is measured piece clamped in the top of the side wall of test cavity, and the contact position of sealing cover body and measured piece is provided with sealing ring.The test tool of the utility model cooperates with high sensitivity helium mass spectrometer leak detector, and high confidence air tightness detection that is directly completed with client end installation test result mutual mapping in factory.

Description

Technical Field

[0001] The utility model belongs to the field of test fixtures, and particularly relates to a air tightness test fixture and system for a machine heating plate. Background Art

[0002] In the field of PCBA (Printed Circuit Board Assembly) manufacturing and quality control, especially in the semiconductor field where extremely high reliability requirements are imposed, the package air tightness is a key indicator that determines product reliability.

[0003] There are two traditional methods for PCBA air tightness verification: one is the pressure holding method (pressure decay method). Usually, the PCBA to be tested is placed in a simple fixture, manually sealed with a rubber plug or a simple joint, a certain pressure of air is charged into the inner cavity of the product, the valve is closed and the product is left standing for a specified period of time, and it is observed whether the reading of the pressure gauge drops beyond a predetermined threshold. If the pressure drop value is within the allowable range, the product is judged to be qualified. However, the pressure holding method is limited by the resolution of the pressure sensor and the influence of ambient temperature fluctuations, and has the problems of insufficient detection accuracy and sensitivity. In addition, due to medium differences and single pressure simulation, the test conditions are disconnected from the real working conditions and cannot replace client-side verification.

[0004] Precisely because of its insufficient reliability, OEM customers usually do not recognize the in-plant test results of the pressure holding method. Manufacturers must transport the samples to the client side, install them in a real complete machine system for hundreds or even thousands of hours of on-hook reliability testing. This process has a complex workflow, difficult resource coordination, an extremely long cycle, and high cost. Moreover, once the test fails, the problem feedback is severely delayed, leading to batch quality risks and significant economic losses.

[0005] Therefore, as a mainstream in-plant detection method, the pressure holding method has insufficient accuracy and confidence to intercept the risk of client-side failures; while the high-precision helium mass spectrometer leak detection technology is available in laboratories, it is difficult to integrate into production lines to achieve fast and reliable batch testing due to reasons such as complex equipment, long test cycles, and the need for professional operation. Contents of the Utility Model

[0006] Aiming at the deficiencies of the prior art, the technical problem to be solved by the utility model is to provide an air tightness test fixture and system for a machine heating plate.

[0007] To achieve the above purpose, on one aspect, the utility model provides an air tightness test fixture for a machine heating plate, comprising a base, a test cavity and a sealing cover; the test cavity is arranged on the base, and the sealing cover and the test cavity clamp the tested part therebetween; wherein, Positioning posts are arranged on the base, for positioning the position of the tested part; The test chamber is a cavity structure, including a bottom and side walls; the side walls are provided with a connection port for connecting a helium mass spectrometer leak detector that runs through the inside and outside of the cavity, and a sealing ring is provided at the contact position between the side walls and the test piece; The sealing cover clamps the test piece to the side wall of the test chamber, and a sealing ring is provided at the contact position between the sealing cover and the test piece.

[0008] Furthermore, the sealing cover includes a cover portion and two wing portions; wherein the two wing portions are respectively disposed on both sides of the cover portion, and the two wing portions are provided with gripping elements.

[0009] Furthermore, the two wings of the sealing cover are provided with positioning holes, through which a portion of the positioning post can pass to position the sealing cover.

[0010] Furthermore, the sealing cover is provided with a positioning pin to position the sealing cover in the correct orientation.

[0011] Furthermore, the bottom inner side of the test chamber is provided with multiple support columns.

[0012] Furthermore, both the test chamber and the sealing cover are provided with sealing grooves for accommodating the sealing ring.

[0013] Furthermore, the sealing groove is a dovetail sealing groove.

[0014] Furthermore, the sealing groove is polished using a V-shaped parallel texture process.

[0015] Another aspect of this utility model provides a machine tool heating plate air tightness testing system, including the aforementioned machine tool heating plate air tightness testing fixture and a helium mass spectrometer leak detector.

[0016] Furthermore, the machine heating plate airtightness testing system also includes a metal ring to temporarily replace the sealing cover.

[0017] The airtightness testing fixture for the heating plate provided by this utility model can realize the sealed state of the tested component in the customer's whole machine. With the help of a high-sensitivity helium mass spectrometer leak detector, it can directly complete the high-confidence airtightness test in the factory and map the results of the customer's installation test. It can quickly and accurately screen out the tiny leakage defects that will only be exposed after the customer's installation on the production site, thereby completely changing the traditional OEM customer verification mode and greatly reducing the testing cost and cycle. Attached Figure Description

[0018] Figure 1 This is a perspective view of an optional embodiment of the present invention;

[0019] Figure 2This is an exploded view of an optional embodiment of the present invention;

[0020] Figure 3 In this utility model Figure 1 A schematic cross-sectional view along the middle section A'-A;

[0021] Figure 4 This is a schematic diagram of the sealing cover in an optional embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the base and test chamber in an optional embodiment of the present invention;

[0023] Figure 6 This is a top view of the base and test chamber in an optional embodiment of the present invention. Detailed Implementation

[0024] like Figure 1 As shown, the machine heating plate air tightness testing fixture provided in a specific embodiment of the present invention includes a base 10, a test chamber 20 and a sealing cover 30. The test chamber 20 is disposed on the base 10, and the sealing cover 30 and the test chamber 20 clamp the test piece 40 between them.

[0025] See Figures 2 to 6 The base 10 is a plate-like structure with chamfered rectangles. In addition to the test chamber 20, it also has multiple positioning posts 11. The test chamber 20 is located in the center of the base 10, and the multiple positioning posts 11 are respectively located on the four sides of the base 10 to position the test piece 40.

[0026] Preferably, eight positioning posts 11 are provided, with two in a group, located near the edge of the base 10. In addition to positioning the measured part 40, two groups of these eight positioning posts 11 are also used to position the sealing cover 30, as detailed below.

[0027] The test chamber 20 is a cylindrical cavity structure, including a bottom 21 and an annular sidewall 22. A connection port 23, penetrating the inside and outside of the cavity, is provided on the sidewall 22, which can be connected to a helium mass spectrometer leak detector. The top of the sidewall 22 serves to support one side of the sealing surface of the test piece 40, and an O-ring seal 24 is provided at the contact position between the top and the test piece 40. The seal 24 allows the test piece 40 and the test chamber 20 to form a sealed cavity.

[0028] Furthermore, the top of the side wall 22 is also provided with a connecting screw hole 25 and a sealing groove 26. The connecting screw hole 25 is for connection with the sealing cover 30. The sealing groove 26 is used to accommodate the O-ring seal 24.

[0029] Preferred, see Figure 3 The sealing groove 26 adopts a dovetail sealing groove, and its bottom is polished with a V-shaped grain pattern to effectively prevent helium from being trapped in the sealing groove 26 and the sealing ring 24, ensuring sealing performance and test accuracy. The bottom 21 of the test chamber 20 is provided with multiple support columns 27 to support one side of the sealing surface of the test piece 40.

[0030] The sealing cover 30 includes a cover portion 31 and two wing portions 32, with the wing portions 32 fixed to both sides of the cover portion 31. The edge of the cover portion 31 is provided with a locating pin 33 and a screw hole 34 to fix the test piece 40 to the test chamber 20. The locating pin 33 is used to position the installation direction of the sealing cover 30. The screw hole 34 allows a screw to pass through. After passing through the screw hole 34 in the cover portion 31 and the through hole in the test piece 40, the screw is screwed into the connecting screw hole 25 in the test chamber 20, thus achieving a fixed connection between the sealing cover 30, the test piece 40, and the test chamber 20.

[0031] Furthermore, a sealing groove 35 is provided on the inner side of the cover portion 31 to accommodate the O-ring seal 36. The O-ring seal 36 can seal the contact position between the sealing cover 30 and the test piece 40, ensuring the accuracy of the test.

[0032] Preferably, the sealing groove 35 also adopts a dovetail sealing groove, and the bottom is polished with a grain-following process. Therefore, the dovetail sealing groove of the sealing cover 30, the O-ring 36, the test piece 40, the dovetail sealing groove of the test chamber 20, and the O-ring 25 can form a sealed cavity after being tightened with screws.

[0033] Furthermore, the two wings 32 of the sealing cover 30 are provided with positioning holes 37 and gripping members 38; the positioning holes 37 allow the positioning pins 11 on the base 10 to pass through to position the sealing cover 30; the gripping members 38 provide a gripping position for the sealing cover 30 to facilitate the installation of the sealing cover 30.

[0034] Based on the above, this utility model embodiment also provides a machine tool heating plate airtightness testing system, including the aforementioned machine tool heating plate airtightness testing fixture and a helium mass spectrometer leak detector. Further, the machine tool heating plate airtightness testing system also includes a metal ring to temporarily replace the sealing cover 30.

[0035] The usage of the machine tool heating plate air tightness testing fixture and system of this utility model is as follows:

[0036] Connect the helium mass spectrometer leak detector to the connection port 23 of the test chamber 20, and remove the sealing cover 30 from the test fixture using the gripping part. Place it upside down on the table. Clean the surfaces of the sealing groove 35 and sealing ring 36 of the test chamber 20 and the sealing cover 30, ensuring they are free of dirt and foreign matter. Place the welded heating plate with the sealing surface facing up on the table and clean the sealing surface; place the heating plate with the sealing surface facing down on the test chamber 20 and clean the non-sealing surfaces; place the sealing cover 30 on the heating plate according to the direction of the positioning pin 33, then insert the screws and tighten them. Evacuate the test chamber 20 using the helium mass spectrometer leak detector to perform an airtightness test on the test piece 40. Next, a helium leak detection rate test is required on the test piece. The test chamber 20 remains under vacuum. Helium is sprayed onto the screw holes and locating pins 33 of the sealing cover 30, the non-sealed surface of the test component 40, the PCB board of the test component 40, and the sealed surface using a helium gas spray probe from a helium gas bag to detect any helium leaks into the test chamber 20. Furthermore, during this test, the sealing cover 30 of the test fixture needs to be removed and replaced with a metal ring (temporary fixture) and tightened. The helium gas leak rate is then detected at the solder joints on the non-sealed surface of the test component 40 using the helium gas spray probe. This detection process is well-known to those skilled in the art and will not be elaborated upon here.

[0037] The machine tool heating plate airtightness testing fixture provided by this utility model not only replaces the traditional pressure holding method and eliminates the lengthy client verification process, but also has the following beneficial effects: (1) Universal compatibility: The original test required on-site installation and testing at the client, which was not only time-consuming but also very expensive. With this utility model, only one air tightness testing fixture is needed to perform air tightness testing. The machine heating plate is divided into E01, E02 and E03 boards, which are finished products after assembly. Therefore, PCB raw materials, pre-assembly semi-finished products and finished products can all be tested using this testing fixture, which meets the requirement of shared testing of raw materials and products, and frees the fixture from the limitation of "single test dedicated".

[0038] (2) Detection accuracy: The precise positioning of the positioning column 11 ensures that the test piece 40 is fully fitted with the test fixture, avoiding "false leakage" caused by positioning deviation (i.e. misjudging the product due to the failure of the fixture's own seal), thus laying the foundation for the reliability of the test results.

[0039] (3) Sealing reliability: The sealing groove 35 and the sealing ring 36 seal the gap between the test chamber 20 and the test piece 40 to prevent the test medium (air, helium) from leaking from the non-test area; the sealing ring 36 is made of rubber composite material and V-shaped longitudinal polishing technology to fully fit the test piece 40, maintain sealing performance, and enable the tooling to achieve high-precision testing; through the configuration of the dovetail sealing groove 35 and the sealing ring 36, the wear of the sealing parts is reduced, the service life is extended, and the problem of frequent disassembly, installation and replacement of sealing parts in traditional tooling is solved.

[0040] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to preferred embodiments, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model's technical solution. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the content of the present utility model's technical solution shall still fall within the scope of the present utility model's technical solution.

Claims

1. A fixture for testing the airtightness of a machine heating plate, characterized in that, It includes a base, a test chamber, and a sealing cover; the test chamber is disposed on the base, and the sealing cover and the test chamber clamp the test piece between them; wherein, The base is provided with a positioning post for positioning the test piece; The test chamber is a cavity structure, including a bottom and side walls; the side walls are provided with a connection port for connecting a helium mass spectrometer leak detector that runs through the inside and outside of the cavity, and a sealing ring is provided at the contact position between the side walls and the test piece; The sealing cover clamps the test piece to the side wall of the test chamber, and a sealing ring is provided at the contact position between the sealing cover and the test piece.

2. The machine tool heating plate airtightness testing fixture according to claim 1, characterized in that, The sealing cover includes a cover portion and two wing portions; wherein the two wing portions are respectively disposed on both sides of the cover portion, and the two wing portions are provided with gripping elements.

3. The machine tool heating plate airtightness testing fixture according to claim 2, characterized in that, The sealing cover has positioning holes on both wings, through which a portion of the positioning post can pass to position the sealing cover.

4. The machine tool heating plate airtightness testing fixture according to claim 2 or 3, characterized in that, The sealing cover is provided with a positioning pin to position the sealing cover in the correct orientation.

5. The machine tool heating plate airtightness testing fixture according to claim 1, characterized in that, The test chamber has multiple support columns on its bottom inner side.

6. The machine tool heating plate airtightness testing fixture according to claim 1, characterized in that, Both the test chamber and the sealing cover are provided with sealing grooves for accommodating the sealing ring.

7. The machine tool heating plate airtightness testing fixture according to claim 6, characterized in that, The sealing groove is a dovetail sealing groove.

8. The machine tool heating plate airtightness testing fixture according to claim 6 or 7, characterized in that, The sealing groove is polished using a V-shaped parallel texture process.

9. A machine tool heating plate airtightness testing system, characterized in that, The instrument includes the machine heating plate air tightness testing fixture as described in any one of claims 1 to 8 and the helium mass spectrometer leak detector.

10. The machine tool heating plate airtightness testing system according to claim 9, characterized in that, The machine heating plate airtightness testing system also includes a metal ring to temporarily replace the sealing cover.

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