Heat conduction gasket matching and cutting system and method based on multi-sensor fusion

Abstract

The invention relates to the field of intelligent processing and manufacturing, in particular to a heat conduction gasket matching and cutting system and method based on multi-sensor fusion, and the system comprises a visual positioning module which is used for scanning a circuit board to obtain the center coordinate and the overall dimension of a heating device; the height measurement module is used for measuring the height values of the heating device and the heat dissipation boss; the cutting module is used for cutting the heat conduction gasket raw material to obtain a gasket piece matched with the heating device; the three-axis movement module is used for driving the height measurement module and the cutting module to move; and the data processing module is used for calculating and converting the data obtained by the height measurement module into heat dissipation gaps and driving the cutting module to cut to obtain the corresponding gasket pieces, so that the whole process from measurement to cutting is integrated and intelligentized, and the assembly precision, efficiency and reliability of the heat conduction gasket are improved.

Description

Technical Field

[0001] This application relates to the field of intelligent manufacturing, and in particular to a system and method for selecting and cutting thermal conductive pads based on multi-sensor fusion. Background Technology

[0002] Thermal pads are used to fill the gaps between heat dissipation bumps and heat dissipation features on circuit boards to improve thermal conductivity. To ensure that the thermal pad thickness is appropriate and to avoid hot spots due to insufficient pressure or damage to heat dissipation devices or solder joints due to excessive pressure, the heat dissipation gap needs to be calculated to select and cut a thermal pad of suitable thickness.

[0003] Currently, to calculate the heat dissipation gap, it is necessary to measure the height of the heat-generating components and heat dissipation bosses, and then subtract the height of the heat-generating components and heat dissipation bosses from the preset distance between the structural components and the circuit board. The height of the heat-generating components and heat dissipation bosses is generally measured using a height gauge with a digital display dial indicator, and a hand-cranked height gauge, such as CN216132378U, can be roughly referenced.

[0004] However, in the entire thermal pad manufacturing process, the measurement, calculation, selection and cutting steps are all independent, which is inefficient and prone to human error. Summary of the Invention

[0005] To improve the processing efficiency and accuracy of thermal conductive pads, this application provides a system and method for selecting and cutting thermal conductive pads based on multi-sensor fusion.

[0006] Firstly, the thermal conductive pad selection and cutting system based on multi-sensor fusion provided in this application adopts the following technical solution.

[0007] A multi-sensor fusion-based thermal pad selection and cutting system includes:

[0008] The vision positioning module is used to scan the circuit board to obtain the center coordinates and outline dimensions of the heat-generating device;

[0009] The height measurement module is used to measure the height of heat-generating components and heat dissipation bosses;

[0010] The cutting module is used to cut a pad that matches the heating element from the thermally conductive pad material.

[0011] The three-axis motion module is used to move the height measurement module and the cutting module.

[0012] The data processing module is used to calculate and convert the data obtained by the height measurement module into heat dissipation gaps and drive the cutting module to cut and obtain the corresponding shims.

[0013] By adopting the above technical solutions, the measurement, calculation, selection and cutting are integrated to achieve intelligent processing of thermal pads throughout the entire process. This allows for more efficient and high-quality cutting of suitable thermal pads for all heat-generating devices on the circuit board, without the need for physical molds. It can also be quickly adapted to design changes, making it suitable for flexible manufacturing modes such as R&D prototyping and small-batch production of multiple varieties.

[0014] Secondly, the method for selecting and cutting thermal conductive pads based on multi-sensor fusion provided in this application adopts the following technical solution.

[0015] The method for selecting and cutting thermal pads based on multi-sensor fusion, which is used in the above-mentioned system for selecting and cutting thermal pads based on multi-sensor fusion, specifically includes the following steps.

[0016] S1. Scan the positioned circuit board to obtain the center coordinates and outline dimensions of the heating device;

[0017] S2. Obtain multiple coordinate points of the heat-generating device and the heat dissipation boss;

[0018] S3. Measure the height of all coordinate points to obtain the height values ​​of the heat-generating device and the heat dissipation boss;

[0019] S4. Calculate the heat dissipation gap based on the height values ​​of all coordinate points;

[0020] S5. Select a thermally conductive pad with a matching thickness according to the heat dissipation gap and position it accordingly;

[0021] S6. Cut the thermal pads corresponding to each heating element according to the outline size of the heating element.

[0022] By adopting the above technical solution, the heat dissipation gap between different heat-generating devices and heat dissipation bosses on the same circuit board is calculated to determine the model and size of the thermal pad that is suitable for each heat-generating device.

[0023] Optionally, in step S2, several coordinate points at the edge of the heating device and several coordinate points on the circuit board near the heating device are obtained, and each coordinate point on the circuit board is close to a corresponding coordinate point of the heating device.

[0024] Optionally, the formula for calculating the height of the heating element in S3 includes:

[0025] ;

[0026] in, For the circuit board The spacing value between each coordinate point and the height measurement module during detection. For the heating device The distance between coordinate points and the height measurement module during detection, where n is the number of coordinate points on the circuit board or heating device.

[0027] By adopting the above technical solution, since the circuit board may experience global warping or local deformation, the height value of the heat-generating device may vary at different locations. Measuring the height of the heat-generating device at a single point may result in hot spots due to insufficient pressure or damage to the heat-generating device or solder joints due to excessive pressure. Therefore, multiple points are used to measure the height value of the heat-generating device to improve the adaptability of the thermally conductive pad obtained by the final cutting.

[0028] Optionally, four coordinate points for the heating element are set, each corresponding to one of the four corner points around the outline of the heating element, offset inward by 1.5mm. Four coordinate points for the circuit board are set, each corresponding to one of the four corner points around the outline of the heating element, offset outward by 1-2mm.

[0029] By adopting the above technical solution, coordinate points on the heating device and the circuit board are selected at the four corners of the heating device, so that the calculated value can better reflect the height value of the heating device.

[0030] Optionally, the coordinate points on the heat dissipation protrusion in S2 are obtained by mirroring the coordinate points on the heat dissipation device and the circuit board based on the X-axis or Y-axis.

[0031] By adopting the above technical solution, the coordinate system can be unified, which helps to quickly calculate the height value of the heat dissipation boss.

[0032] Optionally, the formula for calculating the heat dissipation gap in S4 includes:

[0033] ;

[0034] in, The preset spacing between the circuit board and the structural components. This refers to the height of the heating element. This represents the height of the heat dissipation boss.

[0035] By adopting the above technical solution, and pre-setting different models of circuit boards and structural components, The value is used to quickly calculate the heat dissipation gap.

[0036] Optionally, the recommended thickness calculation formula for the thermally conductive pad in S5 includes:

[0037] ;

[0038] in, For heat dissipation gap, The target compression ratio.

[0039] Optionally, in step S5, the pad model with the smallest thickness difference is selected and recommended from the database, and combined with the outline dimensions of the heating device to obtain a processing data table.

[0040] By adopting the above technical solution, the most suitable thermal conductive pad can be selected from the thicknesses corresponding to different models of thermal conductive pads.

[0041] Optionally, the cutting path in S6 is obtained by combining the contour dimensions of the heating device obtained in S1.

[0042] By adopting the above technical solution, different cutting methods can be selected according to the different materials of the thermal conductive pad.

[0043] In summary, this application includes at least the following beneficial effects:

[0044] 1. It integrates measurement, calculation, selection and cutting to achieve intelligent processing of thermal pads throughout the entire process. It can cut thermal pads suitable for all heat-generating devices on the circuit board with higher efficiency and quality, without the need for physical molds. It can quickly adapt to design changes and is suitable for flexible manufacturing modes such as R&D prototyping and multi-variety small batches.

[0045] 2. Because the circuit board may experience global warping or local deformation, the height value of the heat-generating device may vary at different locations. Measuring the height of the heat-generating device at a single point may result in hot spots due to insufficient pressure or damage to the heat-generating device or solder joints due to excessive pressure. Therefore, it is necessary to measure the height value of the heat-generating device at multiple points to improve the adaptability of the thermal pad obtained in the final cutting. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of a part of the height measurement of heat-generating devices on a circuit board in a multi-sensor fusion-based thermal pad selection and cutting system.

[0047] Figure 2 This is a flowchart illustrating the steps of a method for selecting and cutting thermal conductive pads based on multi-sensor fusion.

[0048] Explanation of reference numerals in the attached diagram: 1. Visual positioning module; 2. Height measurement module; 3. Cutting module; 4. Three-axis motion module; 5. Data processing module. Detailed Implementation

[0049] The present application will be further described in detail below with reference to the accompanying drawings.

[0050] This application discloses a thermal pad selection and cutting system based on multi-sensor fusion, referring to... Figure 1 ,include:

[0051] The visual positioning module 1 is used to scan the circuit board to obtain the center coordinates and outline dimensions of the heating device, and can be a CCD camera and an image processing unit.

[0052] Height measurement module 2 is used to measure the height of the heating device and the heat dissipation boss, and can be a laser displacement sensor.

[0053] Cutting module 3 is used to cut a pad that matches the heating device from the thermally conductive pad material. If the thermally conductive pad is a silicone-based material, a high-frequency vibrating knife is preferred for cutting; if the thermally conductive pad is a composite material such as graphene, a carbon dioxide laser is preferred for cutting.

[0054] The three-axis motion module 4 is used to drive the height measuring module 2 and the cutting module 3 to move. Specifically, precision ball screws, linear guides and servo motors can be used for positioning and movement in the horizontal X and Y axes; two independent electric slides are used in the vertical Z axis so that the height measuring module 2 and the cutting module 3 can be raised and lowered independently.

[0055] The data processing module 5 is used to calculate and convert the data obtained by the height measurement module into a heat dissipation gap and drive the cutting module to cut and obtain the corresponding shim. Specifically, it can be an industrial computer equipped with a multi-axis motion control card.

[0056] This application also discloses a method for selecting and cutting thermal conductive pads based on multi-sensor fusion, referring to... Figure 2 Specifically, it includes the following steps.

[0057] S1. Scan the positioned circuit board to obtain the center coordinates and outline dimensions of the heating device.

[0058] Specifically, a high-resolution monochrome CCD area array camera with a telecentric lens is vertically mounted directly above the circuit board. Uniform illumination is provided by a ring-shaped LED shadowless light source or a coaxial light source to eliminate interference from solder joint reflections. The camera triggers the acquisition of images of the circuit board and transmits them to the image processing unit, where grayscale conversion, Gaussian filtering for noise reduction, and adaptive contrast enhancement are performed.

[0059] For identifying heat-generating devices, two methods can be used. One is based on deep learning, pre-collecting samples of various heat-generating devices to train a YOLOv8 target detection model for fast, coarse localization. The second method uses Canny edge detection within the ROI region to extract contours, combines morphological closing operations to eliminate discontinuities, and then finds the minimum bounding rectangle. Shape matching and size filtering are used to automatically distinguish the type of heat-generating device and accurately locate it. The localization algorithm performs sub-pixel edge fitting on the detection box, calculates geometric moments to obtain the device center coordinates and rotation angle, and the length and width of the bounding rectangle are the contour dimensions. Finally, calibration parameters are used to convert the pixel coordinates into physical coordinates for output.

[0060] S2. Obtain multiple coordinate points of the heat-generating device and the heat dissipation boss.

[0061] Several coordinate points are set at the edge of the heating element, and several coordinate points are set on the circuit board near the heating element. Each coordinate point on the circuit board is close to a corresponding coordinate point of the heating element.

[0062] In this embodiment, four coordinate points for the heating element can be set, each corresponding to one of the four corner points around the outline of the heating element, offset inward by 1.5mm. Four coordinate points for the circuit board can be set, each corresponding to one of the four corner points around the outline of the heating element, offset outward by 1-2mm from the circuit board.

[0063] The coordinates of each point on the heat dissipation protrusion are obtained by mirroring the coordinates of the heat dissipation device and the circuit board based on the X-axis or Y-axis. In this embodiment, the circuit board and the structural components are symmetrical about the Y-axis.

[0064] S3. Measure the height of all coordinate points to obtain the height values ​​of the heat-generating device and the heat dissipation boss.

[0065] The formula for calculating the height of the heating element is as follows.

[0066] ;

[0067] in, For the circuit board The spacing value between each coordinate point and the height measurement module during detection. For the heating device The distance between coordinate points and the height measurement module during detection, where n is the number of coordinate points on the circuit board or heating device.

[0068] The height of the heat dissipation boss can be calculated by referring to the height value of the heat-generating device and by processing the mirror points on the structural component and the heat dissipation boss in the same way.

[0069] S4. Calculate the heat dissipation gap based on the height values ​​of all coordinate points. The calculation formula is as follows.

[0070] ;

[0071] in, A preset spacing is established between circuit boards and structural components, and a mapping table is created between different structural components and different circuit boards. This refers to the height of the heating element. This represents the height of the heat dissipation boss.

[0072] S5. Select a thermally conductive pad with a matching thickness according to the heat dissipation gap and position it accordingly.

[0073] The recommended formula for calculating the thickness of thermal conductive pads is as follows.

[0074] ;

[0075] in, This is a heat dissipation gap. To determine the target compression ratio, a mapping table is established because the compression ratio varies depending on the material of the thermally conductive pad.

[0076] After obtaining the recommended thickness, select the padding model with the smallest difference from the recommended thickness from the database.

[0077] S6. Cut the thermal pads corresponding to each heating element according to the outline size of the heating element.

[0078] The selected thermal pad model is combined with the outline dimensions of the heating element to obtain a processing data sheet. The final pad is then cut according to this data sheet. Furthermore, the cutting path is calculated by combining the outline dimensions of the heating element obtained in step S1, allowing for a single cut to obtain thermal pads corresponding to all heating elements on the circuit board. A safety gap of 2-5mm is maintained between adjacent thermal pads to ensure that the raw material of the thermal pad does not easily deform during the cutting process.

[0079] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A thermal conductive pad selection and cutting system based on multi-sensor fusion, characterized in that: include: The vision positioning module (1) is used to scan the circuit board to obtain the center coordinates and outline dimensions of the heating device; The height measurement module (2) is used to measure the height of the heat-generating device and the heat dissipation boss; The cutting module (3) is used to cut a pad that matches the heating device from the thermally conductive pad material. The three-axis motion module (4) is used to drive the height measurement module (2) and the cutting module (3) to move; The data processing module (5) is used to calculate and convert the data obtained by the height measurement module into a heat dissipation gap and drive the cutting module (3) to cut and obtain the corresponding pad.

2. A method for selecting and cutting thermal conductive pads based on multi-sensor fusion, for use in the thermal conductive pad selection and cutting system based on multi-sensor fusion as described in claim 1, characterized in that: Specifically, the steps include the following: S1. Scan the positioned circuit board to obtain the center coordinates and outline dimensions of the heating device; S2. Obtain multiple coordinate points of the heat-generating device and the heat dissipation boss; S3. Measure the height of all coordinate points to obtain the height values ​​of the heat-generating device and the heat dissipation boss; S4. Calculate the heat dissipation gap based on the height values ​​of all coordinate points; S5. Select a thermally conductive pad with a matching thickness according to the heat dissipation gap and position it accordingly; S6. Cut the thermal pads corresponding to each heating element according to the outline size of the heating element.

3. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 2, characterized in that: In step S2, several coordinate points at the edge of the heating device and several coordinate points on the circuit board near the heating device are obtained. Each coordinate point on the circuit board is close to a corresponding coordinate point of the heating device.

4. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 3, characterized in that: The formula for calculating the height of the heating element in S3 includes: ; in, For the circuit board The spacing value between each coordinate point and the height measurement module during detection. For the heating device The distance between coordinate points and the height measurement module during detection, where n is the number of coordinate points on the circuit board or heating device.

5. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 3, characterized in that: The coordinate points of the heating device are set to four points, each corresponding to one of the four corner points around the outline of the heating device, offset inward by 1.5mm. The coordinate points of the circuit board are set to four points, each corresponding to one of the four corner points around the outline of the heating device, offset outward by 1-2mm.

6. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 2, characterized in that: In S2, the coordinate points of each heat dissipation protrusion are obtained by mirroring the coordinate points on the heat dissipation device and the circuit board based on the X-axis or Y-axis.

7. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 2, characterized in that: The formula for calculating the heat dissipation gap in S4 includes: ； in, The preset spacing between the circuit board and the structural components. This refers to the height of the heating element. This represents the height of the heat dissipation boss.

8. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 2, characterized in that: The recommended thickness calculation formula for the thermal conductive pad in S5 includes: ； in, For heat dissipation gap, The target compression ratio.

9. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 8, characterized in that: In step S5, the gasket model with the smallest thickness difference is selected and recommended from the database, and the processing data table is obtained by combining the outline dimensions of the heating device.

10. The method for selecting and cutting thermal conductive pads based on multi-sensor fusion according to claim 2, characterized in that: The S6 cutting path is calculated by combining the contour dimensions of the heating device obtained from the scan in S1.

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