TWI487838B - Heat dissipation device and airflow generator thereof - Google Patents

Description

Heat sink and its airflow generator

The present invention relates to a heat dissipating device, and more particularly to a heat dissipating device for dissipating heat generated electronic components in an electronic device and an airflow generator therefor.

In electronic devices such as computers, a heat sink is often used to dissipate heat from internal electronic components such as the CPU. The heat dissipating device comprises a heat sink disposed on the electronic component and a heat dissipating fan disposed on the heat sink. The heat sink has a plurality of heat sinks, and the heat dissipating fan operates to generate airflow and blows to the heat sink to transmit the heat sink to the heat sink. Take away the heat.

However, when the cooling fan is operated at a relatively high speed, noise is easily generated and it is possible to cause unstable operation. In addition, in the cooling fan, in order to achieve a certain amount of air, the motor must have a corresponding size, which cannot meet the requirements for the development of the electronic device toward the thin and light.

In view of the above, it is necessary to provide a gas flow generator suitable for miniaturization design and having a good mute effect, and to provide a heat sink using the gas flow generator.

An airflow generator includes a casing and a plurality of airflow generating units disposed in the casing, wherein each airflow generating unit includes a casing, a diaphragm and a driving component, and the diaphragm is disposed in the casing and The inner space of the box is divided into a first chamber and a second chamber, and the second chamber communicates with the outside through an air hole, and the diaphragm is driven by the diaphragm The member compresses the gas in the second chamber and generates a gas stream that is ejected outward from the pore.

A heat dissipating device includes a heat sink and an air flow generator disposed on the heat sink. The airflow generator includes a casing and a plurality of airflow generating units disposed in the casing, wherein each airflow generating unit comprises a casing, a diaphragm and a driving component, and the diaphragm is disposed in the casing and the The inner space of the casing is divided into a first chamber and a second chamber, and the second chamber communicates with the outside through an air hole, and the diaphragm compresses the gas in the second chamber under the action of the driving member and generates An air flow from the air vent to the heat sink.

In the airflow generator of the heat dissipating device, the airflow is generated by the driving member to drive the diaphragm, and the motor, the rotor and the like are not required to be disposed like the cooling fan, so that the air conditioner has a good mute effect. The airflow generating unit has a simple structure and is suitable for a thin design.

100, 100a‧‧‧ heat sink

10‧‧‧ radiator

20, 20a‧‧‧ airflow generator

11‧‧‧heat-absorbing floor

12‧‧‧ Heat sink

13‧‧‧Air passage

14‧‧‧Installation Department

15‧‧‧Mounting holes

30‧‧‧Shell

40, 40a‧‧‧Airflow generating unit

31‧‧‧Base

311‧‧‧ stomata

32‧‧‧Upper cover

321‧‧‧ top board

322‧‧‧ side wall

323‧‧‧Installation Department

324‧‧‧through hole

325‧‧‧Support components

101‧‧‧Locks

41‧‧‧ cabinet

42‧‧‧Densor

43, 43a‧‧‧ drive parts

431‧‧‧Soft iron

432‧‧‧ coil

433‧‧‧ magnet

44‧‧‧ openings

411‧‧‧ first chamber

412‧‧‧Second chamber

A, B‧‧‧ dotted line

102‧‧‧First airflow

103‧‧‧Second airflow

104‧‧‧ arrow

1 is an assembled view of a preferred embodiment of a heat sink of the present invention.

2 is an exploded perspective view of the heat sink shown in FIG. 1.

3 is an exploded perspective view of the airflow generator in the heat sink of FIG. 2.

Figure 4 is an inverted view of Figure 3.

Figure 5 is a cross-sectional view of the heat sink of Figure 1 taken along line V-V.

FIG. 6 is a schematic view showing the working process of the heat sink shown in FIG. 1.

FIG. 7 is still another schematic diagram showing the working process of the heat sink shown in FIG. 1.

FIG. 8 is still another schematic diagram showing the working process of the heat sink shown in FIG. 1. FIG.

Figure 9 is a cross-sectional view showing another embodiment of the airflow generator of the heat sink of the present invention.

A preferred embodiment of the heat sink 100 of the present invention is shown in FIGS. 1 and 2. The heat sink 100 includes a heat sink 10 and an airflow generator 20 disposed on the heat sink 10.

The heat sink 10 includes a heat absorption substrate 11 and a plurality of heat sinks 12 disposed on the heat absorption substrate 11. The heat absorption base 11 is for contacting a heat source such as an electronic component to absorb heat. The fins 12 are disposed in parallel with each other and form an air flow passage 13 between the adjacent fins 12. The four corners of the heat sink 10 respectively have a mounting portion 14 , and each mounting portion 14 is provided with a mounting hole 15 .

Referring to FIG. 3 and FIG. 4 together, the airflow generator 20 includes a casing 30 and a plurality of airflow generating units 40 disposed in the casing 30. The housing 30 includes a base 31 and an upper cover 32 that is disposed on the base 31. The upper cover 32 has a top plate 321 and a side wall 322 extending downward from a periphery of the top plate 321 . The positions of the four corners of the upper cover 32 respectively have a mounting portion 323, and each of the mounting portions 323 is provided with a through hole 324. In addition, a lower side of each mounting portion 323 of the upper cover 32 is provided with a supporting member 325 such as a boss at a position corresponding to the through hole 324. When the airflow generator 20 is mounted on the heat sink 10, the supporting members 325 are correspondingly disposed on the mounting portion 14 of the heat sink 10, and the through holes 324 in the housing 30 are respectively aligned with the mounting holes 15 of the heat sink 10. The airflow generator 20 is fixed to the heat sink 10 by four locking members 101, such as screws, respectively passing through the through holes 324 in the housing 30 and engaging the mounting holes 15 of the heat sink 10. Since the support member 325 is provided between the heat sink 10 and the airflow generator 20, a space is formed between the heat sink 10 and the airflow generator 20.

Referring to FIG. 5 together, the airflow generating units 40 are all received by the base 31 and the upper The cover 32 is enclosed in a receiving space and arranged in an array. Each of the airflow generating units 40 includes a rectangular casing 41, a diaphragm 42 disposed in the casing 41, and a driving member 43 disposed on the diaphragm 42. The housing 41 has a downwardly facing opening 44 (shown in Figure 4). The base 31 of the housing 30 is attached to the bottom of the airflow generating unit 40, and a circular air hole 311 is defined in the base 31 at a position corresponding to the driving member 43 of each airflow generating unit 40.

The diaphragm 42 is horizontally disposed in the casing 41, and isolates the space in the casing 41 into a first chamber 411 and a second chamber 412. The first chamber 411 and the second chamber 412 are respectively located on upper and lower sides of the diaphragm 42 , and the second chamber 412 communicates with the outside through the air hole 311 . The driving member 43 is disposed on the diaphragm 42 and located at an intermediate position of the diaphragm 42. The driving member 43 can generate a periodic motion to drive the diaphragm 42 to vibrate up and down. In this embodiment, the driving member 43 is a piezoelectric sheet (hereinafter also indicated by 43), and the piezoelectric sheet 43 can be bonded to the diaphragm 42 by bonding. The piezoelectric sheet 43 is made of a material having a piezoelectric effect such as a ceramic, a polymer or a composite material. The piezoelectric piece 43 is capable of alternately bending deformation in the thickness direction thereof under the driving of the alternating voltage, thereby causing the diaphragm 421 to generate upper and lower vibrations.

When the airflow generator 20 is in operation, an alternating voltage is applied to the piezoelectric sheet 43 (ie, the driving member) of each airflow generating unit 40, so that the piezoelectric sheet 43 generates alternating bending deformation in the thickness direction thereof and drives the vibration. The membrane 42 generates periodic up-and-down vibrations to repeatedly compress the gas in the second chamber 412 of the casing 41 to generate a high-speed airflow to the radiator 10 at the air holes 311 of the base 31. The airflow quickly enters the airflow passage 13 of the heat sink 10 and exchanges heat with the heat sink 12, thereby carrying away the heat transferred to the heat sink 12.

Referring to FIG. 6-8, a specific motion cycle of the single airflow generating unit 40 is hereinafter. Explain the process of generating airflow.

The process of generating airflow can be divided into three phases. In the first stage, a positive voltage (or a negative voltage) is applied to the piezoelectric sheet 43 of the airflow generating unit 40, so that the piezoelectric sheet 43 is deformed downwardly, and the diaphragm 42 is driven by the piezoelectric sheet 43. Bend down to compress the second chamber 412. As shown in FIG. 6, during the movement of the diaphragm 42 from the initial horizontal position to the position indicated by the broken line A in the figure, the gas in the second chamber 412 is compressed and moved toward the air hole 311, thereby forming a flow from the air hole 311 to the heat dissipation. A first airflow 102 of the device 10 moves forward along the airflow path 13 between the heat sinks 12 and exchanges heat with the heat sink 12 to carry away the heat transferred to the heat sink 12.

In the second stage, an opposite voltage is applied to the piezoelectric sheet 43 of the airflow generating unit 40, so that the piezoelectric sheet 43 is deformed upwardly, and the diaphragm 42 is driven by the piezoelectric sheet 43. The position movement shown by the broken line A at 6 is returned to the horizontal position shown in FIG. During this process, the first airflow 102 entering the airflow passage 13 of the radiator 10 continues to move forward, while the air between the airflow generator 20 and the gap of the radiator 10 is sucked to the heat sink at a position close to the air hole 311. A second air flow 103 is formed in the air flow passage 13 of the device 10, and the flow rate of the second air flow 103 can be up to ten times that of the first air flow 102.

In the third stage, the diaphragm 42 continues to be bent upwardly and moved from the horizontal position shown in Fig. 7 to the position shown by the broken line B in Fig. 8. During this process, the volume of the first chamber 411 is compressed, and the volume of the second chamber 412 is expanded, and the air between the gap between the airflow generator 20 and the radiator 10 is drawn into the second chamber through the air vent 311. Within chamber 412 (shown by arrow 104 in FIG. 8) for use in the next cycle of motion, second airflow 103 entering airflow passage 13 of radiator 10 continues to move forward and pushes first airflow 102 toward For the front movement, the first airflow 102 is near the heat absorbing floor of the heat sink 10. 11 places to the sides.

In the airflow generation unit 40, the piezoelectric film 43 drives the diaphragm 42 to repeatedly perform the periodic motion described above, so that the airflow to the heat sink 10 is continuously generated from the source to take away the heat on the heat sink 10. Further, by applying an alternating voltage of a different period to the piezoelectric sheet 43, the flow rate of the generated gas flow can be controlled so that the gas flow can be sufficiently utilized.

In the heat sink 100, the airflow is supplied by the airflow generator 20 to blow the heat sink 10 to remove the heat of the heat sink 10. The number of airflow generating units 40 in the airflow generator 20 can be selected as desired. The airflow generating unit 40 does not need to provide a motor, a rotor, and the like like a cooling fan, and thus has a good mute effect. The airflow generating unit 40 has a simple structure and is suitable for a thin design.

In the heat sink 100, the driving member 43 of the airflow generating unit 40 of the airflow generator 20 is a piezoelectric sheet, and the driving member 43 may be other components.

Another embodiment of the heat sink 100a of the present invention is shown in FIG. 9. The heat sink 100a also includes a heat sink 10 and a gas flow generator 20a. The difference between the airflow generator 20a and the airflow generator 20 in the previous embodiment is as shown in FIG. Only the driving members 43a used by the airflow generating unit 40a are different. In this embodiment, the driving member 43a disposed on the diaphragm 42 of each airflow generating unit 40a includes a soft iron 431, a coil 432 surrounding the soft iron 431, and a magnet 433. The coil 432 can be directly wound. The soft iron 431 is disposed on the diaphragm 42. The coils 432 of the airflow generating units 40 are connected in series with each other and to an external control circuit. The magnet 433 is located in the first chamber 411, and the magnet 433 is disposed on the casing 41 and disposed opposite to the soft iron 431. The positional relationship of the elements of the driving member 43a can also be reversed, that is, the magnet 433 is disposed on the diaphragm 42 and the soft iron 431 and the coil 432 are disposed on the housing 41.

When the airflow generator 20a is in operation, the soft iron 431 is magnetized by applying an alternating current to the coil 432 of the driving member 43a of each of the airflow generating units 40a. When a forward current is applied to the coil 432, the soft iron 431 is magnetized and its polarity is opposite to the polarity of the magnet 433. At this time, the soft iron 431 and the magnet 433 repel each other, since the magnet 433 is fixed to the case 41, The soft iron 431 moves away from the magnet 433 under the action of the repulsive force, thereby driving the diaphragm 42 to move downward. Conversely, when a reverse current is applied to the coil 432, the soft iron 431 is magnetized and its polarity is the same as the polarity of the magnet 433. At this time, the soft iron 431 and the magnet 433 are attracted to each other, and the soft iron 431 is in the suction force. The lower side moves toward the magnet 433, thereby driving the diaphragm 42 to move upward. The airflow generation process of each airflow generation unit 40a in this embodiment in one exercise cycle is the same as that shown in Figs. 6-8. In addition, by applying an alternating current of different periods to the coil 432, the vibration amplitude of the diaphragm 42 can be controlled, thereby controlling the flow rate of the generated airflow so that the airflow can be fully utilized.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art will be included in the following claims.

10‧‧‧ radiator

13‧‧‧Air passage

31‧‧‧Base

311‧‧‧ stomata

32‧‧‧Upper cover

325‧‧‧Support components

41‧‧‧ cabinet

42‧‧‧Densor

43‧‧‧ drive parts

411‧‧‧ first chamber

412‧‧‧Second chamber

Claims (10)

An airflow generator includes a casing and a plurality of airflow generating units disposed in the casing, wherein the airflow generating unit comprises a casing, a diaphragm and a driving component, wherein the diaphragm is disposed in the casing The body partitions the inner space of the box into a first chamber and a second chamber, the first chamber is a sealed cavity, and the second chamber is vented to the outside by a ventilating hole located at a lower portion thereof In communication, the actuator is facing the air hole, and the diaphragm compresses the gas in the second chamber under the action of the driving member and generates a gas flow which is outwardly ejected from the air hole. The airflow generator of claim 1, wherein the driving member is a piezoelectric piece disposed on the diaphragm. The airflow generator of claim 1, wherein the driving component comprises a soft iron, a coil surrounding the soft iron, and a magnet, the soft iron being disposed in one of the diaphragm or the casing Upper, the magnet is oppositely disposed on one of the diaphragm or the casing in which the soft iron is not disposed. The airflow generator of claim 3, wherein the soft iron is disposed on the diaphragm, and the magnet is disposed on the casing. The airflow generator of claim 4, wherein the coil is wound on the soft iron or disposed on the diaphragm. The airflow generator of claim 1, wherein the housing comprises a base and an upper cover disposed on the base, the airflow generating unit is disposed between the base and the upper cover, and each airflow is generated. The unit is provided with an opening toward the base, and the air hole is disposed on the base. The airflow generator of claim 1, wherein the airflow generating units are distributed in an array. A heat dissipating device, comprising: a heat sink, wherein the heat dissipating device further comprises the airflow generator according to any one of claims 1 to 7, wherein the airflow generator is disposed in the dispersing device On the heat exchanger, the air holes are opposite to the heat sink. The heat dissipating device of claim 8, wherein the heat sink comprises a heat absorbing substrate and a plurality of heat sinks disposed on the heat absorbing substrate, and an air flow passage is formed between the adjacent heat sinks, the air hole and the air flow. The channels are opposite. The heat sink of claim 8, wherein a gap is formed between the airflow generator and the heat sink.