Device for testing oil penetration rate of heat-conducting gasket

Abstract

The utility model provides a device for testing the oil penetration rate of a heat-conducting gasket, and relates to the technical field of heat-conducting gasket oil penetration rate test.The device comprises a metal base, a metal cover plate and a steel sheet, cylindrical rods are machined at the four corners of the top of the metal base, threaded rods are machined at one ends of the cylindrical rods, and two nuts are connected to the outer portions of the threaded rods in a threaded mode; the interior of the steel sheet is adaptively connected with a heat-conducting gasket, filter paper and glass fabric; the technical key points are as follows: the steel sheet internally provided with the circular groove is used for supporting the detection work of the heat-conducting gasket, when the metal cover plate and the metal base approach to apply pressure to the heat-conducting gasket, the heat-conducting gasket can be prevented from excessively extending from the center to the periphery, and the accuracy degree of the oil penetration rate test of the heat-conducting gasket in a fixed range is ensured; by measuring the mass difference between the heat-conducting gasket and the glass fabric before heating and the mass difference between the heat-conducting gasket and the glass fabric after heating and taking the average value of multiple groups of measurement data, the oil seepage rate of the heat-conducting gasket is calculated, and the test accuracy is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of testing the oil seepage rate of a thermally conductive pad, in particular to a device for testing the oil seepage rate of a thermally conductive pad. Background Art

[0002] Thermally conductive pads are used to fill the air gap between heat-generating components and heat sinks or metal bases. They are widely used to cover very uneven surfaces due to their flexible and elastic characteristics. They can conduct heat from separate components or the entire PCB to the metal housing or diffusion plate, thereby improving the efficiency and service life of heat-generating electronic components.

[0003] In the use of gaskets, pressure and temperature are mutually restricted. With the increase of temperature, after the equipment has been running for a period of time, the gasket material will soften, creep, and stress relax, and the mechanical strength will also decrease, and the sealing pressure will be reduced.

[0004] Patent document with publication number CN217359522U discloses a thermal pad compression oil penetration test device that measures the oil penetration rate of thermal pads of different thicknesses at different compression rates by replacing stoppers of different heights;

[0005] By adding an isolation net to isolate the thermal gasket and the oil absorbing paper, the thermal gasket and the oil absorbing paper can be easily separated after testing, and the oil permeability rate of the thermal gasket under specified test conditions can be measured more accurately.

[0006] However, in the process of implementing the above technical solution, it is found that the above technical solution has the following technical problems:

[0007] The existing thermal gasket compression oil penetration test device mainly sets left-right symmetrical limit blocks on the inner side of the device to prevent the thermal gasket from being over-compressed, so as to ensure the detection effect of the thermal gasket oil penetration rate. However, in actual application, since the thermal gasket has no support around it, when compressed by the device, the thermal gasket is easy to extend to the surroundings, thereby reducing the accuracy of the thermal gasket permeability test. Utility Model Content

[0008] In order to overcome the shortcomings of the existing thermal pad compression oil penetration test device, which has no support around the thermal pad, the thermal pad is easily extended to the surroundings when compressed by the device, thereby reducing the accuracy of the thermal pad permeability test, the embodiment of the present application provides a device for testing the oil penetration rate of the thermal pad, which uses a steel sheet with circular grooves processed inside to support the detection work of the thermal pad. When the metal cover plate and the metal base are close to press the thermal pad, the thermal pad can be prevented from excessively extending from the center to the surroundings, thereby ensuring the accuracy of the thermal pad oil penetration rate test within a fixed range;

[0009] At the same time, by attaching a layer of fiberglass cloth to the top and bottom surfaces of the thermal gasket, and setting three layers of filter paper on the surface of the fiberglass cloth, after the thermal gasket, fiberglass cloth and filter paper are fitted and connected inside the steel sheet, and the steel sheet is clamped between the metal cover and the metal base, the oil permeability rate of the thermal gasket can be calculated by measuring the mass difference between the thermal gasket and the fiberglass cloth before heating and the mass difference between the thermal gasket and the fiberglass cloth after heating, and taking the average value of multiple sets of measurement data, which is conducive to ensuring the accuracy of the test.

[0010] The technical solution adopted by the embodiment of the present application to solve the technical problem is:

[0011] A device for testing the oil permeability of a thermally conductive gasket comprises a metal base, a metal cover plate and a steel sheet, wherein the metal cover plate is arranged on the top of the metal base;

[0012] The steel sheet is arranged between the metal base and the metal cover;

[0013] Among them, cylindrical rods are processed at the four corners of the top of the metal base, a threaded rod is processed at one end of the cylindrical rod, the external threaded connection of the threaded rod is connected with two nuts, the inside of the steel sheet is adapted to be connected with a thermal conductive gasket, and the inside of the steel sheet is also adapted to be connected with filter paper and glass fiber cloth.

[0014] In a possible implementation, the diameter of the cylindrical rod is greater than the diameter of the threaded rod, the cylindrical rod passes through the inside of the corner, and the nut is located on the top of the metal cover plate.

[0015] In a possible implementation, the filter paper and the glass fiber cloth are both arranged on the top and bottom of the thermal conductive gasket, and the surface of the glass fiber cloth is in contact with the thermal conductive gasket.

[0016] In a possible implementation, the filter paper on the top or bottom of the thermally conductive gasket is provided with three layers, and the three layers of filter paper are matched with a layer of fiber cloth.

[0017] In summary, the present invention includes at least one of the following beneficial technical effects:

[0018] 1. By using a steel sheet with circular grooves inside to support the testing of the thermal pad, when the metal cover and the metal base are close to press the thermal pad, the thermal pad can be prevented from over-extending from the center to the surroundings, ensuring the accuracy of the thermal pad oil penetration rate test within a fixed range;

[0019] 2. By attaching a layer of fiberglass cloth to the top and bottom of the thermal gasket, and setting three layers of filter paper on the surface of the fiberglass cloth, after the thermal gasket, fiberglass cloth and filter paper are fitted and connected inside the steel sheet, and the steel sheet is clamped between the metal cover and the metal base, the oil permeability rate of the thermal gasket can be calculated by measuring the mass difference between the thermal gasket and the fiberglass cloth before heating and the mass difference between the thermal gasket and the fiberglass cloth after heating, and taking the average value of multiple sets of measurement data, which is conducive to ensuring the accuracy of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0021] Figure 2 This is a schematic diagram of the positional relationship between the steel sheet and the metal base of the utility model;

[0022] Figure 3 It is a cross-sectional view of the metal cover plate of the utility model.

[0023] Description of the drawings: 1. Metal cover; 2. Metal base; 3. Threaded rod; 4. Nut; 5. Cylindrical rod; 6. Thermal pad; 7. Steel sheet. DETAILED DESCRIPTION

[0024] The technical solution in the embodiment of the present application is to solve the problems of the above-mentioned background technology, and the overall idea is as follows:

[0025] Embodiment 1:

[0026] This embodiment introduces a specific structure of a device for testing the oil permeability of a thermally conductive gasket. Figure 1-Figure 3 As shown, it comprises a metal base 2, a metal cover plate 1 arranged on the top of the metal base 2, and a steel sheet 7 arranged between the metal base 2 and the metal cover plate 1;

[0027] Among them, cylindrical rods 5 are processed at the four corners of the top of the metal base 2, and a threaded rod 3 is processed at one end of the cylindrical rod 5. The external threaded connection of the threaded rod 3 is connected with two nuts 4. By placing the metal cover plate 1 on the top of the metal base 2, after the threaded rods 3 and the cylindrical rods 5 at the four corners of the metal base 2 pass through the four corners of the metal cover plate 1, a nut 4 is threadedly connected to the outside of one end of the threaded rod 3, and another nut 4 is threadedly connected to the outside of the threaded rod 3 to squeeze the nut 4 at the bottom, which can limit the connection between the nut 4 and the threaded rod 3 from loosening;

[0028] At the same time, in order to ensure the connection stability between the metal cover plate 1 and the metal base 2, as Figure 3As shown, the diameter of the cylindrical rod 5 is greater than that of the threaded rod 3. By passing the cylindrical rod 5 through the inside of the corner, the nut 4 is located on the top of the metal cover plate 1. The cylindrical rod 5 cooperates with the metal cover plate 1 to limit the left and right movement of the metal cover plate 1 on the top of the metal base 2.

[0029] Secondly, by fitting the circular heat-conducting gasket 6 to the steel sheet 7 with circular grooves inside, and fitting the filter paper and glass fiber cloth inside the steel sheet 7, so that the filter paper and glass fiber cloth are attached to the top and bottom of the heat-conducting gasket 6, the oil absorption of the glass fiber cloth can be judged by testing the difference in weight before and after the glass fiber cloth during the detection process, thereby judging the oil permeability of the heat-conducting gasket 6;

[0030] At the same time, the filter paper on the top or bottom of the thermal pad 6 is provided with three layers, and the three layers of filter paper are matched with a layer of fiber cloth, the fiber cloth is in contact with the surface of the thermal pad 6, and the surface of the fiber cloth away from the thermal pad 6 is in contact with the three layers of filter paper;

[0031] Specifically, the test steps for the oil permeability of the thermal pad are as follows:

[0032] S1: Prepare filter paper and cut it into 60mm diameter discs, 3 discs on the top and 3 discs on the bottom for each group of samples, 18 discs in total for three groups of samples;

[0033] S2: Prepare glass fiber cloth and cut it into 60mm diameter discs, one disc on the top and one disc on the bottom for each group of samples, a total of 18 discs for three groups of samples;

[0034] S3: Prepare the product to be tested, use a mold to take out a circular thermal pad 6 with a diameter of 30 mm and a thickness of 2 mm, use a precision balance (confirm whether the number is zero after powering on, and calibrate with a 100g weight, the digital display deviation should be within 0.0001, otherwise it needs to be calibrated) to weigh and record the data W, measure the thickness of the thermal pad 6 and record the data h0;

[0035] S4: Check whether the metal cover plate 1, the metal base 2 and the steel sheet 7 are dirty or corroded, and put the cut filter paper and glass fiber cloth, as well as the jig and the 1.0 mm steel sheet 7, etc., into a drying oven and bake for 2 hours;

[0036] S5: Each group of samples is attached with a layer of glass fiber cloth and three layers of filter paper on the top and bottom, and the top and bottom are clamped with glass fiber cloth (total weight W2) and filter paper in turn. Then, the threaded rod 3 and the cylindrical rod 5 at the four corners of the metal base 2 pass through the four corners of the metal cover 1, and a nut 4 is threadedly connected to the outside of one end of the threaded rod 3, and another nut 4 is threadedly connected to the outside of the threaded rod 3 to squeeze the nut 4 at the bottom, so that the steel sheet 7 is clamped between the metal cover 1 and the metal base 2 in a limited thickness (the sample is placed in the 1.0mm steel sheet 7), and the distance between the metal cover 1 and the metal base 2 is adjusted to compress the thermal pad 6 by (50±3)% h0;

[0037] S6: Put the metal cover plate 1 and metal base 2 and the 3 groups of samples assembled in S5 into a forced air drying oven, set the temperature to 125°C, take them out after (48±0.5) hours, and place them at room temperature for 2-3 hours, carefully peel off the filter paper, weigh and record the weight W3 of the sample and glass fiber;

[0038] At the same time, when testing the oil permeability of the thermal pad 6, fill in the data in the following table:

[0039]

[0040]

[0041] Next, the oil seepage rate is calculated according to the following formula (calculated in mass units):

[0042] NCR=(W+W2-W3) / W×100%

[0043] Among them, NCR is oil permeability rate, W is the mass of the sample before the test, W2 is the total mass of the glass fiber cloth, and W3 is the total mass of the sample and glass fiber after the test;

[0044] It is worth noting that when using the oil permeability test data of thermal pad 6 to calculate the oil permeability, the average of three measured values ​​is used as the result, and 3 significant digits are retained to ensure the accuracy of the test.

[0045] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. A device for testing the oil permeability of a thermally conductive gasket, characterized in that: include: Metal base (2); A metal cover plate (1) disposed on the top of the metal base (2); A steel sheet (7) disposed between the metal base (2) and the metal cover plate (1); The four corners of the top of the metal base (2) are all processed with cylindrical rods (5), one end of the cylindrical rod (5) is processed with a threaded rod (3), the outside of the threaded rod (3) is threadedly connected with two nuts (4), the inside of the steel sheet (7) is adapted to be connected with a thermal conductive gasket (6), and the inside of the steel sheet (7) is also adapted to be connected with filter paper and glass fiber cloth.

2. A device for testing the oil permeability of a thermally conductive gasket as claimed in claim 1, characterized in that: The diameter of the cylindrical rod (5) is greater than the diameter of the threaded rod (3), the cylindrical rod (5) passes through the inside of the corner, and the nut (4) is located on the top of the metal cover plate (1).

3. A device for testing the oil permeability of a thermally conductive gasket as claimed in claim 1, characterized in that: The filter paper and the glass fiber cloth are both arranged on the top and bottom of the thermal conductive pad (6), and the surface of the glass fiber cloth is in contact with the thermal conductive pad (6).

4. A device for testing the oil permeability of a thermally conductive gasket as claimed in claim 3, characterized in that: The filter paper on the top or bottom of the thermally conductive pad (6) is provided with three layers, and the three layers of filter paper are matched with a layer of fiber cloth.

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