CN114340311A

CN114340311A - Radiator, circuit board and electrical equipment

Info

Publication number: CN114340311A
Application number: CN202111435645.4A
Authority: CN
Inventors: 魏礼贵; 严春飞; 陈智伟; 李明江
Original assignee: Zhangzhou Kehua Technology Co Ltd; Kehua Data Co Ltd
Current assignee: Xiamen Kehua Digital Energy Tech Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-04-12

Abstract

The invention provides a heat sink, a circuit board and an electrical device. The heat sink includes: the first substrate and the second substrate are oppositely arranged; the first fins are arranged on the inner side of the first substrate, and the second fins are arranged on the outer side of the first substrate; the third fins are arranged on the inner side of the second substrate, and the fourth fins are arranged on the outer side of the second substrate; the lower part of the second fin is used for installing a first heating device, the lower part of the fourth fin is used for installing a second heating device, the installation width of the first heating device is equal to the height of the second fin, and the installation width of the second heating device is equal to the height of the fourth fin; the tooth thicknesses of the first fin and the third fin are larger than those of the second fin and the fourth fin; a wind collecting area is formed between the first substrate and the second substrate. The invention can improve the heat dissipation efficiency of the radiator.

Description

Radiator, circuit board and electrical equipment

Technical Field

The invention relates to the technical field of electrical engineering, in particular to a radiator, a circuit board and electrical equipment.

Background

Along with the gradual increase of the installed capacity of the electrical equipment, the heating power consumption of the circuit module in the electrical equipment is correspondingly increased, and higher requirements are put forward for the radiator in the electrical equipment.

Fig. 1 shows a heat sink of the prior art, which includes a substrate 11, a heat sink 12 vertically mounted on the substrate 11, and heat generating devices mounted on two sides of the lower end of the substrate 11. The heat emitted by the heat generating device is conducted to the heat sink through air. During heat dissipation, air flows over the heat generating device and the heat sink, such as the heat generating device surface, the substrate 11 surface, and the heat sink surface. However, since the gap between the heat generating device and the heat dissipating device is large, there may be a serious air leakage phenomenon, so that most of the air flowing through the heat sink passes through the heat dissipating region 13, and the air flow rate on the surface of the heat dissipating fins of the heat sink is relatively reduced, resulting in a reduction in the heat dissipating efficiency of the heat sink.

Disclosure of Invention

The invention provides a radiator, a circuit board and electrical equipment, which can improve the radiating efficiency of the radiator.

In a first aspect, the present invention provides a heat sink comprising: the first substrate and the second substrate are oppositely arranged; the first fins are arranged on the inner side of the first substrate, and the second fins are arranged on the outer side of the first substrate; the third fins are arranged on the inner side of the second substrate, and the fourth fins are arranged on the outer side of the second substrate; the lower part of the second fin is used for installing a first heating device, the lower part of the fourth fin is used for installing a second heating device, the installation width of the first heating device is equal to the height of the second fin, and the installation width of the second heating device is equal to the height of the fourth fin; the tooth thicknesses of the first fin and the third fin are larger than those of the second fin and the fourth fin; the first substrate, the second substrate, the N first fins and the N third fins, or the first substrate, the second substrate and the M communicating parts, form a wind collecting area between the first substrate and the second substrate.

The invention provides a radiator, which comprises a first heat generating device, a second heat generating device, a fourth heat generating device and a heat radiator, wherein the installation width of the first heat generating device is equal to the height of a second fin, and the installation width of the second heat generating device is equal to the height of a fourth fin, so that an air leakage area of the installation position of the heat generating device is reduced, the air volume of the air leakage area is reduced, the air volume of air flowing through the fins of the radiator is increased, and the heat radiation efficiency of the radiator is improved. Secondly, the tooth thicknesses of the first fin and the third fin are larger than those of the second fin and the fourth fin, so that the heat of the radiator is concentrated to the first fin and the third fin, and the heat is radiated through a wind collecting area between the first substrate and the second substrate. Finally, the first substrate, the second substrate, the N first fins and the N third fins, or the first substrate, the second substrate and the M communicating parts form a wind collecting area between the first substrate and the second substrate, so that the heat dissipation air is concentrated in the wind collecting area, and the heat dissipation efficiency of the radiator is further improved through the wind collecting area. Therefore, the heat radiator provided by the invention can improve the heat radiation efficiency of the heat radiator.

In one possible implementation manner, the fins of the first fins, which are close to the upper end of the first substrate, are communicated with the fins of the third fins, which are close to the upper end of the second substrate, and are used for closing the upper ends of the first substrate and the second substrate.

In one possible implementation manner, the fins of the first fins, which are close to the lower end of the first substrate, are communicated with the fins of the third fins, which are close to the lower end of the second substrate, so as to close the lower ends of the first substrate and the second substrate.

In a possible implementation manner, a fin at a first position, close to the first substrate, of the first fins is communicated with a fin at a second position, close to the second substrate, of the third fins, and is used for dividing the wind collecting area into a second wind collecting area and a first wind collecting area which are distributed up and down along the height direction of the radiator; the first position is the position where the temperature of the first substrate is highest when the radiator works, and the second position is the position where the temperature of the second substrate is highest when the radiator works.

In one possible implementation, the plurality of fins of the first fin disposed between the upper end and the lower end are communicated with the plurality of fins of the third fin disposed between the upper end and the lower end, for dividing the wind collecting area into a plurality of sub wind collecting areas.

In one possible implementation, the communication portion includes a first communication portion for communicating upper ends of the first and second substrates, and a second communication portion for communicating lower ends of the first and second substrates.

In one possible implementation, the communication portion further includes a third communication portion disposed at a third position between upper and lower ends of the first and second substrates, the third position being a position where a temperature is highest on the first and second substrates when the heat sink is in operation, and a thickness of the third communication portion is greater than that of the first and second communication portions.

In a possible implementation manner, the first heating device is attached to the first substrate through the first insulating gasket, and the second heating device is attached to the second substrate through the second insulating gasket.

In a second aspect, an embodiment of the present invention provides a circuit board, including: a circuit substrate; a heat sink fixed to the circuit substrate according to the first aspect or any one of the possible implementations of the first aspect; the width of the power device is equal to that of the second/fourth fins of the radiator, and the height of the power device is at least equal to the lower surface of the lowest fin in the second/fourth fins of the radiator.

In a third aspect, an embodiment of the present invention further provides an electrical apparatus, including the heat sink according to the first aspect or any one of the possible implementation manners of the first aspect, and power devices disposed on two sides of the heat sink; the radiator comprises a case, a radiator and a fan, wherein the case is used for installing the radiator, a radiating fan arranged opposite to the radiator is arranged at an opening at the front end of the case, a first wind collecting area main body of the radiator is positioned in an orthographic projection area of blades of the radiating fan, and a second wind collecting area main body of the radiator is positioned in an orthographic projection area of a fan shaft of the radiating fan.

For technical effects brought by any possible implementation manner of the second aspect to the third aspect, reference may be made to technical effects brought by the first aspect or any possible implementation manner of the first aspect, and details are not described here.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic diagram of a heat sink in the prior art;

fig. 2 is a schematic structural diagram of a heat sink according to an embodiment of the present invention;

fig. 3 is a schematic view illustrating arrangement of communication fins on a heat sink according to an embodiment of the present invention;

fig. 4 is a schematic view illustrating arrangement of communication fins on another heat sink according to an embodiment of the present invention;

fig. 5 is a schematic view of a communication part on a heat sink according to an embodiment of the present invention;

fig. 6 is a schematic view of another arrangement of the communication part on the radiator according to the embodiment of the present invention.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

In the description of the present invention, "/" means "or" unless otherwise specified, for example, a/B may mean a or B. "and/or" herein is merely an association describing an associated object, and means that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. Further, "at least one" or "a plurality" means two or more. The terms "first", "second", and the like do not necessarily limit the number and execution order, and the terms "first", "second", and the like do not necessarily limit the difference.

In the embodiments of the present application, words such as "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present relevant concepts in a concrete fashion for ease of understanding.

Furthermore, the terms "including" and "having," and any variations thereof, as referred to in the description of the present application, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or modules is not limited to the listed steps or modules, but may alternatively include other steps or modules not listed or inherent to such process, method, article, or apparatus.

Fig. 1 shows a heat sink of the prior art, which includes a substrate 11, a heat sink 12 vertically mounted on the substrate 11, and heat generating devices mounted on two sides of the lower end of the substrate 11. The heat generating device conducts heat to the heat sink through the substrate 11. In the heat dissipation process, air flows through the surface of the radiator and the surface of the heating device to take away heat generated by the heating device, so that the heat dissipation effect is realized. However, on the other hand, the height of the fins 12 of the heat sink is larger than the width of the heat generating device, and a leakage area is likely to occur in the area 13, so that most of the heat radiation air flows through the leakage area of the area 13, and the heat radiation efficiency of the entire heat sink is low. On the other hand, the height of the heat dissipation fins 12 of the heat sink is set too high, so that the time for the heat in the substrate 11 to be conducted to the tail ends of the heat dissipation fins 12 is longer, the heat conduction efficiency is lower, and the heat dissipation efficiency of the whole heat sink is lower.

To solve the above technical problem, as shown in fig. 2, an embodiment of the present invention provides a heat sink 20, including: a first substrate 21 and a second substrate 22 disposed opposite to each other; a first fin 23 disposed on an inner side of the first substrate 21, and a second fin 24 disposed on an outer side of the first substrate 21; the third fins 25 are disposed on the inner side of the second substrate 22, and the fourth fins 26 are disposed on the outer side of the second substrate 22.

In the embodiment of the present application, the lower portion of the second fin 24 is used for mounting a first heat generating device, the lower portion of the fourth fin 26 is used for mounting a second heat generating device, the mounting width of the first heat generating device is equal to the height of the second fin 24, and the mounting width of the second heat generating device is equal to the height of the fourth fin 26.

It can be understood that the fins are arranged on both sides of the first substrate and the second substrate, and the heights of the second fin and the fourth fin can be reduced, so that the heights of the second fin and the fourth fin can be set to be equal to the installation width of the heat generating device. Furthermore, the height of the second fins and the height of the fourth fins are reduced, so that the time for conducting heat from the substrate to the tail ends of the fins can be reduced, and the heat conduction efficiency of the heat radiator is improved.

In the embodiment of the present application, the first fins 23 and the third fins 25 have a larger tooth thickness than the second fins 24 and the fourth fins 26.

In the embodiment of the present application, the first substrate, the second substrate, the N first fins and the N third fins, or the first substrate, the second substrate, and the M communicating portions, form a wind collecting area located between the first substrate and the second substrate.

In some embodiments, the value of N may be a natural number.

Illustratively, N may take the value 0. N equal to 0 means that the first substrate 21 and the second substrate 22 do not communicate with each other through the fin and the communication portion. The first substrate 21 and the second substrate 22 are arranged oppositely, and the first substrate 21, the second substrate 22, and the first fin 23 and the third fin 24 between the two substrates form a wind collecting area.

As another example, N may be an integer greater than 0, which means that the first substrate 21 and the second substrate 22 are communicated with each other through one or more fins, or through one or more communication portions. The first substrate 21, the second substrate 22 and the one or more fins form a wind collecting area. Alternatively, the first substrate 21, the second substrate 22, and one or more communication portions constitute a wind collecting area.

In one possible implementation, the first fins 23, which are close to the upper end of the first substrate 21, communicate with the third fins 25, which are close to the upper end of the second substrate 22, to close the upper ends of the first substrate 21 and the second substrate 22.

Illustratively, as shown in fig. 3, the fin of the first fins 23 near the upper end of the first substrate 21 is communicated with the fin of the third fins 25 near the upper end of the second substrate 22, that is, the upper end of the first substrate 21 and the upper end of the second substrate 22 are provided with first communicating fins 27. The first communication fin 27 closes the upper ends of the first and

second substrates

21 and 22.

It can be understood that the first substrate 21, the second substrate 22 and the first communication fins 27 at the upper ends form a wind collecting area, which can reduce wind leakage at the upper ends of the first substrate 21 and the second substrate 22 during the heat dissipation process, so that more heat dissipation air flows over the surfaces of the fins in the wind collecting area during the circulation process, thereby improving the wind collecting effect of the wind collecting area and improving the heat dissipation efficiency of the heat sink 20.

In one possible implementation, the fin of the first fins 23, which is close to the lower end of the first substrate 21, communicates with the fin of the third fins 25, which is close to the lower end of the second substrate 22, for closing the lower end of the first substrate 21 and the lower end of the second substrate 22.

Illustratively, as shown in fig. 3, the fins of the first fins 23 near the lower end of the first substrate 21 communicate with the fins of the third fins 25 near the lower end of the second substrate 22, that is, the lower end of the first substrate 21 and the lower end of the second substrate 22 are provided with second communication fins 28. The second communication fin 28 closes the lower ends of the first and

second substrates

21 and 22.

Note that the first communication fin 27 closes the upper end of the first substrate 21 and the upper end of the second substrate 22. The second communication fin 28 closes the lower ends of the first and

second substrates

21 and 22. Therefore, the first communicating fins 27, the second communicating fins 28, the first substrate 21 and the second substrate 22 form a closed air collecting area, so that air flowing between the first substrate 21 and the second substrate 22 can only flow from the air inlet to the air outlet, the problem of air leakage in the process from the air inlet to the air outlet is avoided, the problem of air leakage in the air circulation process is avoided, and the heat dissipation efficiency of the heat sink 20 is improved.

In a possible implementation manner, a fin at a first position of the first fins 23 close to the first substrate 21 is communicated with a fin at a second position of the third fins 25 close to the second substrate 22, and is used for dividing the wind collecting area into a second wind collecting area and a first wind collecting area which are distributed up and down along the height direction of the heat sink; the first position is the position where the temperature of the first substrate is highest when the radiator works, and the second position is the position where the temperature of the second substrate is highest when the radiator works.

Illustratively, as shown in fig. 4, a third communication fin 29 is disposed at a middle position between the first substrate 21 and the second substrate 22. The third communicating fin 29 divides the wind collecting area into a first wind collecting area and a second wind collecting area. The first wind collecting area is an area below the third communicating fin 29, and the second wind collecting area is an area above the third communicating fin 29.

Based on the embodiment shown in fig. 4, the third communicating fin 29 divides the wind collecting area into the first wind collecting area and the second wind collecting area. After the heat of the heating device is conducted to the substrate, the heat can be dissipated through the first wind collecting area, can be conducted to the second wind collecting area through the substrate to dissipate the heat, and can be conducted to the second fins and the fourth fins through the substrate to dissipate the heat.

Therefore, the radiator is divided into three stages of radiating structures by the two substrates which are oppositely arranged and the three communicated fins. A first stage: the heat of the heating device passes through the substrates and reaches the outer sides of the two substrates, and the second fins and the fourth fins dissipate heat. And a second stage: the heat of the heat device is dissipated to the second air collecting area through the substrate, the air collecting effect is better than that of the first level, and the heat dissipation effect is better. And a third stage: the heat of the heating device is dissipated to the first wind collecting area through the substrate, the heat conduction distance is shortest, the wind collecting effect is better than that of the outer side of the substrate, and the heat dissipation effect is best. The invention improves the heat dissipation efficiency of the heat radiator through the three-level heat dissipation structure.

In one possible implementation, the plurality of first fins 23 disposed between the upper end and the lower end are communicated with the plurality of third fins 25 disposed between the upper end and the lower end for dividing the wind collecting area into a plurality of sub wind collecting areas.

It should be noted that the two substrates are provided with the plurality of communicating fins, so that the wind collecting area can be divided into the plurality of sub wind collecting areas, the wind collecting area division is realized, the multistage heat dissipation structure is constructed, the heat dissipation efficiency of the heat sink is improved, the heat conduction between the heat sinks can be enhanced, and the integral temperature equalizing performance of the heat sink is improved.

In one possible implementation, the communication portion includes a first communication portion for communicating the upper ends of the first and

second substrates

21 and 22, and a second communication portion for communicating the lower ends of the first and

second substrates

21 and 22.

Illustratively, as shown in fig. 5, the first communicating portion 31 is provided at upper ends of the first and

second substrates

21 and 22, for transferring heat between the first and

second substrates

21 and 22, and for closing the upper ends of the first and

second substrates

21 and 22. The second communication portion 22 is provided at the lower ends of the first and

second substrates

21 and 22, for transferring heat between the first and

second substrates

21 and 22, and for closing the lower ends of the first and

second substrates

21 and 22.

The first communicating portion 31, the second communicating portion 32, the first substrate 21, and the second substrate 22 constitute a wind collecting area. Compared with the embodiment shown in fig. 3, in the heat sink shown in fig. 5, the first substrate 21 and the second substrate 22 are connected by the communication portion, the thickness of the communication portion is larger than that of the fin, heat transfer between the first substrate 21 and the second substrate 22 is faster, and the temperature equalization performance between the first substrate 21 and the second substrate 22 is better.

In one possible implementation, the communication portion further includes a third communication portion, the third communication portion is disposed at a third position between the upper end and the lower end of the first substrate 21 and the second substrate 22, the third position is a position where the temperature is highest on the first substrate 21 and the second substrate 22 when the heat sink is in operation, and the thickness of the third communication portion is larger than the first communication portion 31 and the second communication portion 32.

For example, as shown in fig. 6, a third communicating portion 33 may be provided at an intermediate position between the first substrate 21 and the second substrate 22 to divide the wind collecting region into a second wind collecting region and a first wind collecting region distributed vertically in the height direction of the radiator.

For example, as shown in fig. 6, the first heat generating device 34 is disposed below the second fins 24, and is attached to the first substrate 21 through the first insulating pad 35. The second heat generating device 36 is disposed below the fourth fins 26, and is attached to the second substrate 22 through a second insulating spacer 37.

In some embodiments, the heat transfer efficiency of the first insulating pad 35 and the heat transfer efficiency of the second insulating pad 37 are greater than that of air, so that heat generated by the first heat generating device 34 and the second heat generating device 36 can be transferred to the first substrate 21 and the second substrate 22 more quickly, and heat dissipation is achieved through the fins mounted on the first substrate 21 and the second substrate 22, thereby improving the heat dissipation efficiency of the heat sink.

It should be noted that, based on the embodiments shown in fig. 4 and fig. 6, there may be a case where the first heat generating device 34 and the second heat generating device 36 operate alternately. For example, assuming that the first heat generating device 34 and the second heat generating device 36 are power devices in the uninterruptible power supply UPS, when the first heat generating device 34 is in the commercial power state, the second heat generating device 36 is in the battery state, that is, the first heat generating device 34 is in the operating state, and the second heat generating device 36 is in the non-operating state.

For the situation that the first heat generating device 34 and the second heat generating device 36 work alternately, when the first heat generating device 34 generates heat, the second heat generating device 36 does not generate heat, and the heat sink shown in fig. 4 can conduct the heat from the first substrate 21 to the second substrate 22 through the communicating fins, so that the temperature equalization of the first substrate 21 and the second substrate 22 is realized, and the heat dissipation efficiency of the heat sink is improved. The heat sink shown in fig. 6 can conduct heat from the first substrate 21 to the second substrate 22 through the communication portion, so that the temperature equalization between the first substrate 21 and the second substrate 22 is realized, and the heat dissipation efficiency of the heat sink is improved.

Therefore, the radiator provided by the embodiment of the invention can solve the problem that the radiating effect is not ideal when the heating devices work alternately, and the radiating efficiency of the radiator is improved by improving the temperature equalizing effect of the two substrates in the radiator.

In some embodiments, the first substrate 21 and the second substrate 22 are fixed to the circuit board by a fixing member. For example, the fixing member may fix the lower ends of the first and second substrates to the circuit board.

An embodiment of the present invention provides a circuit board, including: a circuit substrate; a heat sink as in the previous embodiments is fixed to the circuit substrate.

In this embodiment, the heat sink further includes power devices disposed on two outer sides of the heat sink. The width of the power device is equal to the width of the fins on two sides of the radiator, and the height of the power device is at least equal to the lower surface of the lowest fin in the fins on two sides of the radiator.

In this way, in the embodiment of the present invention, the power device and the second fins 24 and the fourth fins 26 of the heat sink form the semi-closed space, so that when the first heat generating device 34 and the second heat generating device 36 are arranged in the semi-closed space for convection heat dissipation, the heat dissipation airflow can greatly flow through the surfaces of the first heat generating device 34 and the second heat generating device 36, thereby reducing the leakage of the heat dissipation airflow, and improving the heat dissipation efficiency.

An embodiment of the present invention further provides an electrical apparatus including the heat sink as described in the above embodiments.

In this embodiment, the electrical apparatus further includes power devices disposed on both sides of the heat sink.

In this embodiment, the chassis is configured to mount the heat sink, a heat dissipation fan disposed opposite to the heat sink is disposed at an opening at a front end of the chassis, a first wind collecting area main body of the heat sink is located in an orthographic projection area of blades of the heat dissipation fan, and a second wind collecting area main body of the heat sink is located in an orthographic projection area of a fan shaft of the heat dissipation fan.

Therefore, the heat dissipation efficiency of the heat sink is improved by the following technical means

1. The first heating device is arranged below the second fins 24, the second heating device is arranged below the fourth fins 26, the installation width of the first heating device is equal to the height of the second fins 24, the installation width of the second heating device is equal to the height of the fourth fins 26, and meanwhile, the power devices are arranged below the two outer fins of the radiator. The width of the power device is equal to the width of the fins on the two sides of the radiator, and the height of the power device is at least equal to the lower surface of the lowest fin of the fins on the two sides of the radiator, so that the problem of leakage of radiating airflow outside the first heating device and the second heating device is solved.

2. By providing the first fin 23 and the third fin 25, the tooth thickness of the first fin 23 and the third fin 25 is larger than the tooth thickness of the second fin 24 and the fourth fin 26. Thereby improving the conduction efficiency of the heat sink on the fins on the one hand and enabling the heat sink to concentrate heat mainly on the first fins 23 and the third fins 25 when the heat is conducted.

3. A wind collecting area located between the first substrate and the second substrate is formed by the first substrate, the second substrate, N first fins arranged in a communicated mode and N third fins arranged in a communicated mode, or the first substrate, the second substrate and M communicating portions arranged in a communicated mode. Therefore, the heat dissipation airflow is concentrated in the area, so that the heat and the heat dissipation airflow are concentrated in the concentrated area, and the overall efficiency of the radiator is greatly improved.

4. The first heating device is arranged below the second fins 24, the second heating device is arranged below the fourth fins 26, a first air collecting area and a second air collecting area are arranged in the inner sides of the two radiating substrates, meanwhile, the main body of the first air collecting area of the radiator is positioned in the orthographic projection area of the blades of the radiating fan, and the main body of the second air collecting area of the radiator is positioned in the orthographic projection area of the fan shaft of the radiating fan. In this way, the first wind collecting area is closest to the heating element, so that the heat is most concentrated, and the heat radiating fan blades are opposite to the first wind collecting area, so that the air volume is most concentrated, and the efficiency of the first wind collecting area is best.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.

Claims

1. A heat sink, comprising:

the first substrate and the second substrate are oppositely arranged;

the first fins are arranged on the inner side of the first substrate, and the second fins are arranged on the outer side of the first substrate;

the third fins are arranged on the inner side of the second substrate, and the fourth fins are arranged on the outer side of the second substrate;

the lower part of the second fin is used for mounting a first heating device, the lower part of the fourth fin is used for mounting a second heating device, the mounting width of the first heating device is equal to the height of the second fin, and the mounting width of the second heating device is equal to the height of the fourth fin;

the tooth thicknesses of the first fin and the third fin are larger than those of the second fin and the fourth fin;

the first substrate, the second substrate, the N first fins arranged in a communicated manner, the N third fins arranged in a communicated manner, or the first substrate, the second substrate and the M communicating portions arranged in a communicated manner form a wind collecting area between the first substrate and the second substrate.

2. The heat sink as claimed in claim 1, wherein the fins of the first fins near the upper end of the first substrate communicate with the fins of the third fins near the upper end of the second substrate for closing the upper ends of the first and second substrates.

3. The heat sink as claimed in claim 2, wherein the fins of the first fins near the lower end of the first substrate communicate with the fins of the third fins near the lower end of the second substrate for closing the lower ends of the first and second substrates.

4. The heat sink according to claim 3, wherein a fin of the first fin at a first position close to the first substrate is communicated with a fin of the third fin at a second position close to the second substrate, so as to divide the wind collecting area into a second wind collecting area and a first wind collecting area which are distributed vertically along a height direction of the heat sink; the first position is the position where the temperature of the first substrate is highest when the radiator works, and the second position is the position where the temperature of the second substrate is highest when the radiator works.

5. The heat sink as claimed in claim 1 or 3, wherein a plurality of the first fins disposed between the upper end and the lower end communicate with a plurality of the third fins disposed between the upper end and the lower end for dividing the wind collecting area into a plurality of sub wind collecting areas.

6. The heat sink according to claim 1, wherein the communication portion includes a first communication portion for communicating upper ends of the first substrate and the second substrate, and a second communication portion for communicating lower ends of the first substrate and the second substrate.

7. The radiator according to claim 1 or 6, wherein the communication portion further includes a third communication portion provided at a third position between upper and lower ends of the first and second substrates, the third position being a position where a temperature is highest on the first and second substrates when the radiator is operated, the third communication portion having a thickness larger than that of the first communication portion and the second communication portion, the third communication portion being configured to divide the wind collecting region into a second wind collecting region and a first wind collecting region which are distributed vertically in a height direction of the radiator.

8. The heat sink of claim 1, wherein the first heat generating device is attached to the first substrate via a first insulating spacer, and the second heat generating device is attached to the second substrate via a second insulating spacer.

9. A circuit board, comprising:

a circuit substrate;

the heat sink of any one of claims 1 to 8 secured to the circuit substrate;

the width of the power device is equal to that of the second/fourth fins of the radiator, and the height of the power device is at least equal to that of the lower surface of the lowest fin in the second/fourth fins of the radiator.

10. An electrical device, comprising:

a circuit substrate, the heat sink of claim 4 or 7, a power device disposed on both sides of the heat sink;

the radiator comprises a case, a radiator and a fan, wherein the case is used for installing the radiator, a radiating fan arranged opposite to the radiator is arranged at an opening at the front end of the case, a first wind collecting area main body of the radiator is positioned in an orthographic projection area of blades of the radiating fan, and a second wind collecting area main body of the radiator is positioned in an orthographic projection area of a fan shaft of the radiating fan.