CN219536379U - Heat dissipation structure of circuit board - Google Patents

Abstract

The utility model relates to a heat dissipation structure of a circuit board, which comprises: a circuit board and a heat sink; the circuit board is provided with a plurality of MOS tubes; the MOS tubes are arranged on the front surface of the circuit board in a scattered arrangement mode; the radiator is provided with a heat conducting surface; no component is arranged on the back of the circuit board; the distance between the back surface of the circuit board and the heat conducting surface is more than or equal to 0.2mm and less than or equal to 0.8mm; the back of the circuit board is smeared with heat conducting glue and stuck to the heat conducting surface; the circuit board is provided with a plurality of through holes corresponding to the heating devices; when the circuit board is adhered to the heat conducting surface through the heat conducting glue, the heat conducting glue is extruded into the through hole. The beneficial effects of the utility model are as follows: has better heat dissipation effect.

Description

Heat dissipation structure of circuit board

Technical Field

The utility model relates to a circuit board heat dissipation structure.

Background

The brushless electronic water pump, hereinafter referred to as water pump, is widely applied to heat dissipation systems in various industries, and the water pump is increasingly developed towards integration and miniaturization due to smaller power. As the water pump is smaller, the heat dissipation problem becomes a concern.

Most of the traditional circuit board radiating structures adopt a component surface radiating mode to radiate heat, and as the component welding has a certain floating height, the distance between the component surface and the radiating structure is far away so as to reserve enough safety distance. The larger spacing can lead to a great deal of waste of heat conducting glue, and the radiating efficiency is low.

Disclosure of Invention

The present utility model is directed to a heat dissipation structure for a circuit board, so as to solve the above-mentioned problems in the prior art.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

a circuit board heat dissipation structure comprising: a circuit board and a heat sink; the circuit board is provided with a plurality of MOS tubes; the MOS tubes are arranged on the front surface of the circuit board in a scattered arrangement mode; the radiator is provided with a heat conducting surface; no component is arranged on the back of the circuit board; the distance between the back surface of the circuit board and the heat conducting surface is more than or equal to 0.2mm and less than or equal to 0.8mm; the back of the circuit board is smeared with heat conducting glue and stuck to the heat conducting surface; the circuit board is provided with a plurality of through holes corresponding to the heating devices; when the circuit board is adhered to the heat conducting surface through the heat conducting glue, the heat conducting glue is extruded into the through hole.

As a further scheme of the utility model: the wall of the through hole is provided with a metal heat conduction material.

As a further scheme of the utility model: the metal heat conducting material is connected with copper sheets of all layers of the circuit board.

As a further scheme of the utility model: the through holes are positioned at one side or a plurality of sides of the heating device, and the through holes positioned at the same side of the heating device are distributed in a plurality of rows.

As a further scheme of the utility model: the back of the circuit board is provided with a heat dissipation window without an insulating layer; the heat dissipation window is covered by heat conduction glue in contact.

As a further scheme of the utility model: the diameter of the through hole is 15mil or more and 60mil or less.

As a further scheme of the utility model: the diameter of the through hole was 20mil.

As a further scheme of the utility model: the distance between the back surface of the circuit board and the heat conducting surface was set to 0.5mm.

As a further scheme of the utility model: the radiator is a motor shell.

As a further scheme of the utility model: the circuit board heat radiation structure is applied to the circuit board of the water pump.

Compared with the prior art, the utility model has the beneficial effects that: has better heat dissipation effect.

The high-temperature stability of the whole controller is improved.

The main change is PCBA aspect, and production implementation is convenient, can effectively improve production efficiency.

The miniature process of the water pump controller is facilitated to be driven.

Other features and advantages of the present utility model will be disclosed in the following detailed description of the utility model and the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of a front side of a circuit board heat dissipation structure according to the present utility model;

FIG. 2 is a schematic diagram illustrating the mounting of a circuit board and a heat sink of the heat dissipation structure of the circuit board of FIG. 1;

fig. 3 is a schematic view of a window opening position of a back surface of a circuit board of the heat dissipation structure of the circuit board in fig. 1.

List of reference numerals: circuit board 21, heat conductive adhesive 22, heat sink 23, and hatched portions (31, 32).

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 1 to 3, in an embodiment of the utility model, a circuit board heat dissipation structure includes: a circuit board 21 and a heat sink 23. The circuit board 21 is provided with a plurality of MOS transistors. The MOS transistors are disposed on the front surface of the circuit board 21 in a distributed arrangement. As a specific embodiment, the circuit board 21 is a glass fiber board.

As shown in fig. 1, the numbers 1-7 in fig. 1 are 7 MOS positions, which occupy about 70% of the area of the circuit board 21, so that the heat is not concentrated on the circuit board 21, the heat is uniformly distributed on the circuit board 21, and then the heat is led out by adopting a large-area gluing mode.

The heat sink 23 is provided with a heat conducting surface. The back surface of the circuit board 21 is not provided with components. The distance between the back surface of the circuit board 21 and the heat conductive surface is 0.2mm or more and 0.8mm or less. Specifically, the distance between the back surface of the circuit board 21 and the heat conductive surface was set to 0.5mm. As shown in fig. 2, since the clearance between the back surface of the circuit board 21 and the heat conduction surface is small, a large amount of waste of the heat conduction adhesive is not caused.

The back of the circuit board 21 is coated with heat-conducting glue 22 and stuck to the heat-conducting surface. The circuit board 21 is formed with a plurality of through holes. The through hole corresponds to the heating device. When the circuit board 21 is adhered to the heat conducting surface by the heat conducting glue 22, the heat conducting glue 22 is pressed into the through hole.

Specifically, through holes are designed below the MOS tube, and are uniformly distributed, and a non-plugging hole design is adopted. The heat generated by the MOS tube is mainly concentrated on the drain electrode, because the surface of the MOS drain electrode can be covered with a thick insulating layer, the heat dissipation effect of the heat conducting glue 22 contacted by the insulating layer is limited, so that the heat dissipation means can be concentrated on the surface mounting position of the MOS tube, the heat is transferred to the back surface of the circuit board 21 by utilizing the heat conducting characteristic of the copper sheet of the circuit board 21 and the through hole with larger aperture, and the back surface of the circuit board 21 has no component, so that the distance between the heat radiator 23 and the circuit board 21 is small, and the heat conducting design is realized.

As a specific embodiment, the hole wall of the through hole is provided with a metal heat conducting material. The metal heat conductive material connects copper sheets of the layers of the circuit board 21.

In a specific embodiment, the diameter of the through hole is 15mil or more and 60mil or less. The diameter of the through hole was 20mil.

Specifically, the metal heat conducting material is connected with copper sheets of each layer of the circuit board 21, and because the aperture of the through hole is larger, the heat dissipation gap is smaller, when the back of the circuit board 21 is coated with the heat conducting glue 22 for assembly, the heat conducting glue 22 can be extruded into the through hole to fill up gaps in the through hole, and because the through hole is of a penetrating design, the heat conducting glue 22 can reach the plane of the component through the through hole, and plays a good positive role in heat dissipation of the component.

4X4 and 16 square through holes with the aperture of 12mil (0.3048 mm) are also designed below the drain electrode bonding pad of the MOS tube, and the through holes can greatly increase the electrical connection of each layer of the circuit board 21, so that the heat dissipation requirement can be met while the large current passes through. Because the drain electrode bonding pad tin paste is fixed during the surface mounting, a gap exists in the middle of the through hole after welding, and when the heat conducting glue 22 is fully coated and accumulated, the heat conducting glue 22 is extruded into the gap of the through hole, and the heat conducting glue can be fully filled, so that a good positive effect on heat dissipation of components can be achieved.

As a specific embodiment, the plurality of through holes are located at one side or a plurality of sides of the heating device, and the through holes located at the same side of the heating device are arranged in a plurality of rows. Specifically, large-aperture through holes which are uniformly distributed are designed around the heating device, and the heating device is surrounded by adopting a non-hole plugging design.

As a specific embodiment, the back surface of the circuit board 21 is provided with a heat dissipation window. The heat dissipation window is free of an insulating layer. The heat dissipation window is covered by the heat conductive glue 22. As shown in fig. 3, the heat dissipation window design is added to the back of the circuit board 21, and the heat dissipation window design is a shadow part (31, 32), i.e. no insulating layer covers, and the heat conduction glue 22 acts between two metal layers, so that the heat conduction efficiency of the circuit board 21 is improved.

As a specific embodiment, the heat sink 23 is a motor housing.

As a specific embodiment, the heat dissipation structure of the circuit board 21 is applied to the circuit board 21 of the water pump.

Compared with the traditional independent heat dissipation of the components of the traditional circuit board, such as the cores of the CPU and the like, the radiator is flat and convenient to simulate. The utility model can radiate the heat of the main heating source of the whole circuit board. Specifically, the plurality of MOS transistors are disposed on the front surface of the circuit board 21 in a distributed arrangement. For example, 1-7 in fig. 1 are 7 MOS positions, which occupy about 70% of the area of the circuit board 21, which is favorable for heat dissipation, and this way can ensure that heat is not concentrated on the circuit board 21, so that the heat is uniformly distributed on the circuit board 21, and then the heat is conducted out by using a large-area gluing method. It should be noted that, the area of the front surface of the circuit board 21 having the heat generating source needs to be soldered, and the back surface of the circuit board 21 needs to be kept flat, so that the circuit board 21 can be well bonded to the heat conducting surface completely, and the heat conducting and radiating efficiency is improved. Specifically, when the circuit board 21 and the heat sink 23 are actually mounted, it is necessary to apply an appropriate amount of heat conductive surface to the surface to be bonded to the heat conductive surface so as to fill the fine gaps and improve the heat conduction efficiency. When the heat generated by the heat generating source during operation is transferred to the circuit board 21 by contacting with the circuit board 21, the heat is quickly transferred to the radiator 23 with excellent heat conduction performance through the circuit board 21 due to good heat conduction effect of the glass fiber board, and the heat dissipation effect is further improved. Therefore, the heat source on the whole circuit board 21 can rapidly radiate heat through the radiator with larger volume during operation, so that the whole problem of the circuit board 21 can be ensured to be in a normal working range, and the working reliability of the circuit board 21 is ensured.

It will be evident to those skilled in the art that the utility model is not limited to the details of the foregoing illustrative embodiments, and that the present utility model may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.

Claims (10)

1. A circuit board heat dissipation structure, comprising: a circuit board and a heat sink; the circuit board is provided with a plurality of MOS tubes; the MOS tubes are arranged on the front surface of the circuit board in a scattered arrangement mode; the radiator is provided with a heat conducting surface; the back of the circuit board is not provided with components; the distance between the back surface of the circuit board and the heat conducting surface is more than or equal to 0.2mm and less than or equal to 0.8mm; the back of the circuit board is smeared with heat conducting glue and stuck to the heat conducting surface; the circuit board is provided with a plurality of through holes corresponding to the heating devices; when the circuit board is adhered to the heat conducting surface through the heat conducting glue, the heat conducting glue is extruded into the through hole.

2. The circuit board heat dissipating structure of claim 1, wherein,

and the wall of the through hole is provided with a metal heat conduction material.

3. The circuit board heat dissipating structure of claim 2, wherein,

the metal heat conduction material is connected with copper sheets of all layers of the circuit board.

4. The circuit board heat dissipating structure of claim 1, wherein,

the through holes are positioned on one side or a plurality of sides of the heating device, and the through holes positioned on the same side of the heating device are distributed in a plurality of rows.

5. The circuit board heat dissipating structure of claim 1, wherein,

the back of the circuit board is provided with a heat dissipation window without an insulating layer; the heat dissipation window is covered by heat conduction glue in a contact mode.

6. The circuit board heat dissipating structure of claim 1, wherein,

the diameter of the through hole is 15mil or more and 60mil or less.

7. The circuit board heat dissipating structure of claim 6, wherein,

the diameter of the through hole was 20mil.

8. The circuit board heat dissipating structure of claim 1, wherein,

the distance between the back surface of the circuit board and the heat conducting surface is set to 0.5mm.

9. The circuit board heat dissipating structure of claim 1, wherein,

the radiator is a motor shell.

10. The circuit board heat dissipating structure of claim 9,

the circuit board heat radiation structure is applied to a circuit board of the water pump.