A fixing structure of a circuit board

Abstract

The utility model discloses a kind of fixed mounting structures of circuit board, including circuit board, support substrate, heat dissipation substrate and fastening assembly, power device side of circuit board is fixed on support substrate, form circuit board assembly, threaded hole is equipped on support substrate, and it is counterbore on the back surface and circuit board contact;Flat head screw is housed in threaded hole, the flat end of flat head screw is located in the side of support substrate and has counterbore, and its screw end terminal is provided with a slot.Screw hole corresponding with support substrate threaded hole is equipped on heat dissipation substrate;Fastening assembly includes screw and screw sleeve, screw passes through screw sleeve and is inserted from the screw end center hole of flat head screw, is screwed into the screw hole of heat dissipation substrate, and circuit board assembly is fastened on heat dissipation substrate.The fixed mounting structure of the circuit board in the application support substrate is equipped with flat head screw integrated with installation and disassembly function, can save circuit board space, while facilitating maintenance.The utility model structure is simple, low in cost, and can improve maintenance efficiency.

Description

Technical Field

[0001] This utility model relates to the technology for fixing and installing circuit boards and their components, specifically to a fixing and installing structure for a circuit board. Background Technology

[0002] Switching power supplies mainly consist of functional circuits such as EMI circuitry, surge suppression, power factor correction, high-voltage filtering, DC / DC conversion, microcontroller control, and auxiliary power supply. Due to space constraints, to meet functional requirements, the circuit layout is generally implemented using a single integrated circuit board within the existing space. In the maintainability design of highly integrated circuit boards, current technology typically mounts the integrated circuit board onto a support board to form a circuit board assembly, and then the assembly is installed and disassembled as a whole. This design introduces a support board structure, increasing the feasibility of circuit board maintenance and providing a certain degree of protection. Highly integrated circuit boards are often accompanied by high power consumption, which usually requires a matching cooling system to transfer heat from the power devices to the cooling system for heat dissipation. From a practical heat dissipation perspective, adding a support board to the circuit board actually adds a thermal resistance between the heat-generating device and the heat sink, affecting overall heat dissipation. To reduce the impact of adding a support board on the heat dissipation of the power devices, thermal grease is usually evenly applied to the bottom of the support board and the contact surface with the heat sink. Applying thermal grease over a large area improves the overall heat dissipation effect, but it also increases the adhesion between the support board and the heat sink. When repairing modules, the strong adhesive force makes module removal difficult and affects the repair progress; initial disassembly and assembly methods such as pushing, prying, and desoldering may damage components and reduce product reliability. Summary of the Invention

[0003] To address the problem of difficult maintenance and disassembly after the support plate structure of the circuit board assembly is applied with thermal grease and fixed to the heat sink in the prior art, this utility model provides a fixed installation structure for the circuit board, which has the characteristics of simple structure, low cost and convenient disassembly and assembly.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A circuit board mounting structure includes: a circuit board on which power devices are mounted, a support substrate, a heat dissipation substrate, and a fastening assembly; the side of the circuit board where the power devices require heat dissipation is fixed to the support substrate to form a circuit board assembly; the support substrate has a threaded through hole, and on the back side of the support substrate that contacts the circuit board, the threaded through hole is a countersunk hole; a flat-head screw is installed in the threaded through hole, the flat-head screw has a through hole in its center, and a slot is formed at the end of the screw; the flat end of the flat-head screw is installed on the side of the support substrate with the countersunk hole; the heat dissipation substrate has a threaded hole corresponding to the threaded through hole of the support substrate; the fastening assembly includes a screw and a threaded sleeve, the screw is fitted into the threaded sleeve, and then passes through the center hole of the screw end of the flat-head screw mounted on the support substrate, and is screwed into the threaded hole of the heat dissipation substrate to fasten the circuit board assembly to the heat dissipation substrate.

[0006] Furthermore, the screw end of the flat-head screw installed in the threaded hole on the support substrate protrudes from the end face of the support substrate, and the flat-head end is recessed into the countersunk hole of the support substrate.

[0007] Furthermore, the threaded sleeve in the fastening assembly has a threaded hole, which is used in conjunction with the screw in the fastening assembly to form a screw assembly that does not come out.

[0008] Furthermore, the supporting substrate is made of a thermally conductive metal material.

[0009] Furthermore, the circuit board on which the power device is mounted has an operating hole at the location on the corresponding support substrate where a flat-head screw is mounted.

[0010] Furthermore, thermally conductive silicone grease is applied between the supporting substrate and the power device housing on the circuit board that requires heat dissipation, and thermally conductive silicone grease is applied between the supporting substrate and the heat dissipation substrate.

[0011] The circuit board fixing and mounting structure provided by this utility model, adopting the above-mentioned technical solution, has the following beneficial effects: A flat-head screw integrating installation, fixing, and disassembly functions is installed on the support substrate in the circuit board assembly. Installation and disassembly can share the same hole position, eliminating the need for additional holes and saving circuit board space. During maintenance, the fastening components are removed, and the support substrate is lifted by the flat-head screw, reducing the adhesive force between the support substrate and the heat dissipation substrate, allowing the electrical components to detach from the heat-conducting substrate. This utility model has a simple structure, low cost, simple and convenient operation, and high maintenance efficiency. Attached Figure Description

[0012] Figure 1 These are three views of an embodiment of the circuit board fixing and mounting structure of this utility model.

[0013] Figure 2 This is a perspective view of the fixed installation structure of the circuit board of this utility model.

[0014] Figure 3 These are three views of the circuit board assembly in an embodiment of this utility model.

[0015] Figure 4 The following are three views of the flat-head screw in an embodiment of this utility model.

[0016] Figure 5 This is a cross-sectional view of the threaded sleeve in an embodiment of this utility model.

[0017] Figure 6 This is a cross-sectional view of the screw assembly that does not come out, formed by the engagement of the screw sleeve and the screw in the fastening assembly of this utility model embodiment.

[0018] In the diagram: 1. Circuit board assembly; 2. Circuit board; 301. Supporting substrate; 302. M6 flat-head screw; 401. M3 screw sleeve; 5. Heat dissipation substrate; 402. M3 screw; 4. Non-removable screw assembly. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments.

[0020] like Figures 1-3 As shown, in one embodiment of the circuit board fixing and mounting structure of this utility model, there are a circuit board 2 on which power devices are mounted, a support substrate 301, an M6 flat-head screw 302, a heat dissipation substrate 5, and an M3 screw sleeve 401 and an M3 screw 402 in the fastening assembly; the support substrate 301 is made of thermally conductive metal material.

[0021] The circuit board 2, with the power device mounted on one side, is fixed to the support substrate 301 to form the circuit board assembly 1. The support substrate 301 is also designed with a threaded through hole, and the end of the threaded through hole on the back side of the contact surface between the support substrate 301 and the circuit board 2 is a countersunk hole. An M6 flat-head screw 302 is installed in the threaded through hole. The center of the M6 ​​flat-head screw 302 has a through hole of φ3.4. The end of the screw is designed to be tapered and has a slot. The flat end of the M6 ​​flat-head screw 302 is installed on the side of the support substrate with the countersunk hole, and the flat end is recessed into the countersunk hole. The screw end of the M6 ​​flat-head screw 302 protrudes from the end face of the support substrate 301.

[0022] A threaded hole corresponding to the threaded through hole of the support substrate is provided on the heat dissipation substrate 6. An M3 screw 402 in the fastening assembly is fitted into an M3 threaded sleeve 401, and then passed through the center hole of the screw end of an M6 flat-head screw 302 mounted on the support substrate 301, and screwed into the threaded hole of the heat dissipation substrate 5, thus fastening the circuit board assembly 1 to the heat dissipation substrate 5. During maintenance, the fixed M3 screw 402 and M3 threaded sleeve 401 are removed, and a flathead screwdriver is used to utilize the slot on the M6 ​​flat-head screw 302 on the support substrate 301 of the circuit board assembly 1 to separate the circuit board assembly from the heat sink. In practical applications, an operating hole is provided on the circuit board corresponding to the flat-head screw mounted on the support substrate for easy operation.

[0023] The M6 ​​flat-head screw 302 in the embodiment is as follows Figure 4 As shown, it has a through hole of φ3.4 through the center, and the end of the screw is designed to be tapered and has a slot.

[0024] The M3 threaded sleeve 401 in the embodiment is as follows Figure 5 As shown, the inner diameter of the sleeve on one side of the M6 ​​flat-head screw 302 is larger than the outer diameter of the screw end of the M6 ​​flat-head screw 302; the M3 screw sleeve 401 provides support so that the M6 ​​flat-head screw 302 does not contact the M3 screw 402, preventing excessive pressure on the M6 ​​flat-head screw 302 when the M3 screw 402 is directly screwed in, while ensuring the effectiveness of the fastening between the circuit board assembly 1 and the heat sink substrate 5.

[0025] like Figure 6 As shown in this embodiment of the present invention, the screw sleeve in the fastening assembly has a threaded hole, which, together with the screw, forms a non-removable screw assembly 4.

[0026] In this embodiment, thermally conductive silicone grease is uniformly applied to the contact surfaces of the power device housing on the circuit board with the support substrate 301 and the heat dissipation substrate 5.

[0027] Based on the above, the circuit board fixing and mounting structure of this utility model has the advantages of simple structure, low cost, improved maintenance efficiency, and shared mounting and disassembly holes. It solves the problem in the prior art where, after the circuit board is integrated, the contact surface between the support plate and the heat sink is mechanically fixed by applying thermal grease, leading to difficulties in disassembly and assembly during maintenance. Simultaneously, the shared mounting and disassembly hole design alleviates the problem of high wiring pressure on integrated circuit boards, making it worthy of promotion. The basic principles, main features, and advantages of this utility model have been shown and described above. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The main features and advantages of this utility model have been shown and described above. Those skilled in the art should understand that this utility model is not limited to the above embodiments.

[0028] Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model shall be included within the protection scope of this utility model.

Claims

1. A fixed mounting structure for a circuit board, characterized in that, The novel fixed installation structure includes: a circuit board on which power devices are mounted, a support substrate, a heat dissipation substrate, and a fastening assembly; the side of the circuit board where the power devices require heat dissipation is fixed to the support substrate to form a circuit board assembly; a threaded through hole is provided on the support substrate, and on the back side of the support substrate that contacts the circuit board, the threaded through hole is a countersunk hole; a flat-head screw is installed in the threaded through hole, the flat-head screw has a through hole in its center, and a slot is opened at the end of the screw, the flat end of the flat-head screw is installed on the side of the support substrate with the countersunk hole; the heat dissipation substrate has a threaded hole corresponding to the threaded through hole of the support substrate; the fastening assembly includes a screw and a threaded sleeve, the screw is fitted into the threaded sleeve, and then passes through the center hole of the screw end of the flat-head screw mounted on the support substrate, and is screwed into the threaded hole of the heat dissipation substrate to fasten the circuit board assembly to the heat dissipation substrate.

2. The circuit board fixing and mounting structure according to claim 1, characterized in that: The screw end of the flat-head screw installed in the threaded hole on the support substrate protrudes from the end face of the support substrate, and the flat end is recessed into the countersunk hole of the support substrate.

3. The circuit board fixing and mounting structure according to claim 1, characterized in that: The fastening assembly has a threaded sleeve with a threaded hole, which works with the screw in the fastening assembly to form a screw assembly that does not come out.

4. The circuit board fixing and mounting structure according to claim 1, characterized in that: The supporting substrate is made of thermally conductive metal material.

5. The circuit board fixing and mounting structure according to claim 1, characterized in that: The circuit board on which the power device is mounted has an operating hole at the location on the corresponding support substrate where a flat-head screw is mounted.

6. The circuit board fixing and mounting structure according to claim 1, characterized in that: Thermal grease is applied between the supporting substrate and the power device housing on the circuit board that requires heat dissipation, and thermal grease is applied between the supporting substrate and the heat dissipation substrate.

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