Circuit board component height measuring device and method

Abstract

The invention discloses a circuit board component height measuring device and method, and belongs to the technical field of tool gauges, the device comprises a leveling holder, an optical vibration isolation platform and a height gauge; the main body to be tested is a circuit board to be tested; the leveling holder is placed on the optical vibration isolation platform and is used for simulating a heat conduction structure used by an actual electric box; a to-be-tested circuit board is placed on the lower side of the leveling holder; the mounting interface of the leveling holder corresponds to the mounting interface of the to-be-tested circuit board in position, and the leveling holder and the to-be-tested circuit board are connected together through the mounting interface of the leveling holder and the mounting interface of the to-be-tested circuit board; the height gauge is placed on the optical vibration isolation platform and is arranged close to the center of the surface of a certain component to be measured and on one side of a circuit board to be measured, so that a probe of the height gauge can be in contact with the surface of the component to be measured. The height of the circuit board component can be accurately measured, and the design of a heat conduction structure is guided.

Description

Technical Field

[0001] This invention belongs to the field of tooling and inspection technology, specifically relating to a device and method for measuring the height of circuit board components. Background Technology

[0002] In aerospace electronic equipment (such as focal plane electronic boxes), the mechanical thermal conductivity design of circuit boards directly affects thermal control performance and reliability.

[0003] Thermal pad / gap filler configuration is a common mechanical thermal conductivity design for circuit boards, often used in low-cost thermal control solutions for commercial satellites. Its design feature is the filling of a flexible thermally conductive material (such as silicone grease, graphene pads, or phase change materials) between the circuit board and the casing / heat sink, reducing the contact thermal resistance between the circuit board and the casing / heat sink. The heat conduction path between the circuit board and the casing / heat sink is: circuit board → thermal pad → thermally conductive structure → casing. Therefore, controlling the gap between the component surface and the thermally conductive structure surface is crucial. If the gap exceeds the thickness of the thermal pad, no thermal conductivity will occur, and in severe cases, it may even cause high-temperature damage to the components on the circuit board. If the gap is too small, the thermal pad may crack due to excessive compression, resulting in debris and other consequences. Therefore, effective gap control between the circuit board component surface and the thermally conductive structure surface is of significant practical importance.

[0004] Existing heat dissipation systems primarily focus on the design and optimization of the heat dissipation structure itself. For example, strict tolerances are used to control the processing of the heat dissipation structure during the production stage, theoretically controlling the gap between the surface of the heat dissipation structure and the surface of the components to improve heat dissipation reliability.

[0005] However, the above measures only work well when the circuit board itself is flat. They cannot perform fine gap control on severely warped circuit boards and cannot simulate the actual gap height when the circuit board is installed, which has obvious defects. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A height measuring device for circuit board components includes: a leveling clamp, an optical vibration isolation platform, and a height gauge; the subject to be measured is the circuit board to be measured.

[0008] A leveling clamp is placed on an optical vibration isolation platform to simulate the heat-conducting structure used in an actual electrical box. The circuit board under test (TBT) is placed under the leveling clamp. The mounting interface of the leveling clamp corresponds to the mounting interface of the TBT, and the leveling clamp and the TBT are connected together through the mounting interface of the leveling clamp and the TBT. A height gauge is placed on the optical vibration isolation platform, positioned near the center of the surface of a component under test and on one side of the TBT, so that the probe of the height gauge can contact the surface of the component under test.

[0009] A method for measuring the height of circuit board components, used in the aforementioned circuit board component height measuring device, comprising:

[0010] Step 1: Use a height gauge to measure the height t from the mounting interface surface of the circuit board to be tested to the upper surface of the leveling clamp.

[0011] Step 2: Use a height gauge to measure the height difference C1 between the upper surface of the leveling clamp and the upper surface of the component.

[0012] Step 3, calculate the height h of the component under test. C1 ;

[0013] Step 4: Obtain the finishing depth h = h of the boss surface of the thermally conductive structure relative to the mounting interface surface of the circuit board under test. C1 + The thickness of the thermal pad after lamination at the theoretically optimal heat dissipation efficiency.

[0014] The present invention has the following beneficial effects:

[0015] This invention simulates the state of the circuit board under test mounted on a heat-conducting structure by designing a leveling clamp, thus realizing that the actual application scenario of the circuit board is taken into account when measuring the height of the circuit board components. It can accurately measure the height of the circuit board components and guide the design of the heat-conducting structure.

[0016] This invention measures the height of the component under test and then calculates the theoretical gap between the surface of the component under test and the surface of the heat-conducting structure boss. This provides guidance for the design of the heat-conducting structure. By machining the height of the heat-conducting structure boss, the actual gap can be made close to the theoretical value. This ensures that the height of the heat-conducting pad filled inside can be close to the theoretical gap during formal installation, thereby better utilizing the heat-conducting effect of the heat-conducting pad and avoiding problems such as poor adhesion of the heat-conducting pad or crushing and generating excess material.

[0017] This invention eliminates the need for complex moving mechanisms, and the height gauge and optical vibration isolation platform used can be standard shelf products, ensuring the reliability of the measurement while maintaining a simple and low-cost measurement system structure. Attached Figure Description

[0018] Figure 1 This is a top view of the circuit board component height measuring device of the present invention, wherein 1-circuit board to be tested, 3-leveling clamp, 4-first component to be tested, 5-second component to be tested, 6-third component to be tested, 7-fourth component to be tested, and 8-fifth component to be tested.

[0019] Figure 2 This is a front view of the circuit board component height measuring device of the present invention, wherein 1-the circuit board to be measured, 2-height ruler, 3-leveling clamp, 10-the upper surface of the leveling clamp, and 11-optical vibration isolation platform.

[0020] Figure 3 This is a side view of the circuit board component height measuring device of the present invention, wherein 10 is the upper surface of the leveling clamp and 12 is the mounting interface surface of the circuit board to be measured.

[0021] Figure 4 This is an isometric view of the thermally conductive structure of the present invention, wherein 13 is the mounting interface surface of the thermally conductive structure, 14 is the thermally conductive structure, 15 is a boss on the thermally conductive structure corresponding to the first component under test, 16 is a boss on the thermally conductive structure corresponding to the second component under test, 17 is a boss on the thermally conductive structure corresponding to the third component under test, 18 is a boss on the thermally conductive structure corresponding to the fourth component under test, and 19 is a boss on the thermally conductive structure corresponding to the fifth component under test. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] This invention measures the height of the components on the circuit board under test (1), and then calculates the theoretical gap between the surface of the components and the surface of the heat-conducting structure boss. This theoretical gap provides guidance for the design of the heat-conducting structure. By machining the height of the boss of the heat-conducting structure, the actual gap can be made close to the theoretical value. This ensures that the height of the heat-conducting pad filled in during formal installation is close to the theoretical gap, thereby better utilizing the heat-conducting effect of the heat-conducting pad and avoiding problems such as poor adhesion of the heat-conducting pad or crushing and generating excess material.

[0024] like Figure 1 , Figure 2As shown, the present invention provides a circuit board component height measuring device (hereinafter referred to as a testing device), including: a leveling clamp 3, an optical vibration isolation platform 11 and a height ruler 2; the subject to be measured is the object that is installed and fixed, namely the circuit board to be measured 1.

[0025] The embodiment takes a circuit board under test (TBD) 1 that includes 5 Components Under Test (DUTs). The Components Under Test of the circuit board under test 1 include: Component 4 (first DUT), Component 5 (second DUT), Component 6 (third DUT), Component 7 (fourth DUT), and Component 8 (fifth DUT). Figure 1 As shown.

[0026] The leveling clamp 3 is placed on the optical vibration isolation platform 11 to simulate the heat-conducting structure used in an actual electrical box. The actual heat-conducting structure 14 used in an actual electrical box is as follows: Figure 4 As shown, the hole distribution and flatness of the mounting interface surface 13 of the actual electrical box's heat-conducting structure need to be consistent with the mounting interface surface of the leveling clamp. The height difference between the surface of the bosses of the actual electrical box's heat-conducting structure (including: boss 15 on the heat-conducting structure corresponding to the first component under test, boss 16 on the heat-conducting structure corresponding to the second component under test, boss 17 on the heat-conducting structure corresponding to the third component under test, boss 18 on the heat-conducting structure corresponding to the fourth component under test, and boss 19 on the heat-conducting structure corresponding to the fifth component under test) and the mounting interface surface 13 of the heat-conducting structure needs to be less than the height difference between any component under test and the mounting interface surface 12 of the circuit board under test, so as to ensure that the boss surface of the heat-conducting structure has sufficient margin for subsequent fine repair.

[0027] The circuit board under test 1 is placed under the leveling clamp 3. The leveling clamp 3 and the circuit board under test 1 are connected together through the mounting interface of the leveling clamp 3 and the mounting flange interface of the circuit board under test 1.

[0028] The height gauge 2 is positioned on one side of the circuit board 1 under test, close to the center of the surface of the component under test. The mounting interface of the leveling clamp 3 corresponds to the mounting flange interface of the circuit board 1 under test, and the leveling clamp 3 and the circuit board 1 under test are connected together through the mounting interface of the leveling clamp 3 and the mounting interface of the circuit board 1 under test. The flatness requirements of the upper surface 10 of the leveling clamp and the mounting interface surface of the leveling clamp are consistent with the mounting interface surface 13 of the heat-conducting structure used in the actual electrical box and the boss surface of the heat-conducting structure. To reduce error transmission, both the height gauge 2 and the leveling clamp 3 need to be placed on the optical vibration isolation platform 11.

[0029] By setting openings on the upper surface 10 of the leveling clamp corresponding to the positions of the components on the circuit board 1 to be tested, the probe of the height gauge 2 can contact the surface of the components.

[0030] The height gauge 2 and optical vibration isolation platform 11 can be replaced by a higher-precision coordinate measuring machine (CMM). After mounting the circuit board 1 to be tested on the leveling clamp 3, the leveling clamp 3 is placed directly on the three-axis granite platform provided with the CMM. The component height is then measured using the high-precision probe of the CMM according to the above method. This invention also provides a method for measuring the height of circuit board components. The calculated component height guides the precision repair of the height from the boss surface of the heat-conducting structure used in the actual electrical box to the mounting interface surface 12 of the circuit board to be tested, thereby accurately controlling the filling gap of the heat-conducting pad. Taking the measurement process of the first component 4 to be tested as an example, the method for measuring the height of circuit board components of this invention includes the following steps:

[0031] Step 1: Use height gauge 2 to measure the height t from the mounting interface surface 12 of the circuit board to be tested to the upper surface 10 of the leveling clamp.

[0032] Step 2: Use a height gauge 2 to measure the height difference C1 between the upper surface 10 of the leveling clamp and the upper surface of the component.

[0033] Step 3: If the upper surface of the component under test is 10 mm lower than the upper surface of the leveling clamp, then calculate the height h of the component under test. C1 =t-C1; If the upper surface of the component under test is 10 mm higher than the upper surface of the leveling clamp, then calculate the height h of the component under test. C1 =t+C1.

[0034] Step 4: Obtain the finishing depth h = h_t on the surface of the heat-conducting structure boss relative to the mounting interface surface 12 of the circuit board under test. C1 + The thickness of the thermal pad after lamination at the theoretically optimal heat dissipation efficiency.

[0035] The height difference between the upper surface of any component under test and the mounting interface surface 12 of the circuit board under test must be positive, and all components under test must be on the same side of the mounting interface surface 12.

[0036] The above description is merely an embodiment of the present invention and does not limit the scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related system fields, are similarly included within the protection scope of the present invention.

[0037] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A device for measuring the height of circuit board components, characterized in that, include: Leveling clamp, optical vibration isolation platform and height gauge; the subject under test is the circuit board under test; A leveling clamp is placed on an optical vibration isolation platform to simulate the heat-conducting structure used in an actual electrical box. The circuit board under test (TBT) is placed under the leveling clamp. The mounting interface of the leveling clamp corresponds to the mounting interface of the TBT, and the leveling clamp and the TBT are connected together through the mounting interface of the leveling clamp and the TBT. A height gauge is placed on the optical vibration isolation platform, positioned near the center of the surface of a component under test and on one side of the TBT, so that the probe of the height gauge can contact the surface of the component under test.

2. The circuit board component height measuring device according to claim 1, characterized in that, The flatness requirements of the upper surface of the leveling clamp and the mounting interface surface of the leveling clamp must be consistent with the mounting interface surface of the heat-conducting structure used in the actual electrical box.

3. The circuit board component height measuring device according to claim 1, characterized in that, An opening is provided on the upper surface of the leveling clamp corresponding to the position of the component on the circuit board to be tested, so that the probe of the height gauge contacts the surface of the component.

4. The circuit board component height measuring device according to claim 1, characterized in that, The circuit board under test includes several components to be tested.

5. The circuit board component height measuring device according to claim 1, characterized in that, A coordinate measuring machine (CMM) is used instead of a height gauge and an optical vibration isolation platform; the circuit board to be tested is mounted on a leveling clamp, which is placed on the three-axis granite platform that comes with the CMM.

6. The circuit board component height measuring device according to claim 1, characterized in that, Height gauges and optical vibration isolation platforms are standard products for shelving.

7. The circuit board component height measuring device according to claim 1, characterized in that, The hole distribution and flatness of the mounting interface surface of the thermal conductive structure are consistent with those of the mounting interface surface of the leveling clamp. Before fine finishing, the height difference between the boss surface of the thermal conductive structure and the mounting interface surface of the thermal conductive structure is less than the height difference between the upper surface of any component under test and the mounting interface surface of the circuit board under test.

8. The circuit board component height measuring device according to any one of claims 1 to 7, characterized in that, The height difference between the upper surface of all components under test and the mounting interface surface of the circuit board under test must be positive, and all components under test must be on the same side of the mounting interface surface.

9. A method for measuring the height of circuit board components, used in the circuit board component height measuring device as described in any one of claims 1 to 8, characterized in that, include: Step 1: Use a height gauge to measure the height t from the mounting interface surface of the circuit board to be tested to the upper surface of the leveling clamp. Step 2: Use a height gauge to measure the height difference C1 between the upper surface of the leveling clamp and the upper surface of the component. Step 3, calculate the height h of the component under test. C1 ; Step 4: Obtain the finishing depth h = h_t on the surface of the heat-conducting structure's boss relative to the mounting interface surface of the circuit board under test. C1 + The thickness of the thermal pad after lamination at its theoretically optimal heat dissipation efficiency.

10. The method for measuring the height of circuit board components according to claim 9, characterized in that, In step 3, if the upper surface of the component under test is lower than the upper surface of the leveling clamp, then the height h of the component under test is calculated. C1 =t-C1; If the upper surface of the component under test is higher than the upper surface of the leveling clamp, then calculate the height h of the component under test. C1 =t+C 1。

Images