TWI850655B - Centrifugal heat dissipation fan - Google Patents

Abstract

A centrifugal heat dissipation fan including a hub, a frame, and a blade set is provided. The blade set surrounds the hub and keeps a distance from the hub in radial direction. The frame is connected between the hub and the blade set, wherein a plurality of blades of the blade set and the frame are combined with each other by heterogeneous materials.

Description

Centrifugal cooling fan

The present invention relates to a heat dissipation fan, and in particular to a centrifugal heat dissipation fan.

As the design trend of portable electronic devices (such as laptops or tablets) gradually moves towards being thinner and lighter, the cooling fans installed therein are also required to be thinner in the case of extremely limited internal space. As a result, the airflow of the cooling fan cannot smoothly enter and exit the cooling fan in the case of limited space, thus affecting its cooling efficiency.

Take centrifugal cooling fans as an example. Currently, the fan blades are made of metal. Compared with fan blades made of plastic materials through injection molding, metal materials can indeed obtain thinner fan blade structures to obtain more air volume and stronger wind pressure.

However, existing metal blades also face the following problems: as the number of blades increases, the joint between them and the wheel hub also expands, thereby hindering the air flow at the suction point of the centrifugal cooling fan. At the same time, metal blades cannot be thinned and the number of blades cannot be increased indefinitely, because once the thickness reaches below a certain level, the metal blades will deform, which is not conducive to air flow and is prone to noise. Similarly, when the number of blades exceeds a certain number, it will face difficulties in assembly or manufacturing.

Therefore, how to change the relevant structure of the existing centrifugal cooling fan to deal with the above-mentioned problems is indeed a topic that relevant technical personnel need to think about.

The present invention provides a centrifugal cooling fan, which provides a blade set at a distance from the wheel hub on the outer periphery of the wheel hub, and uses a wheel frame as a bridge to enhance the heat dissipation performance.

The centrifugal heat dissipation fan of the present invention includes a wheel hub, a wheel frame and a fan blade assembly. The fan blade assembly surrounds the wheel hub and maintains a distance from the wheel hub in the radial direction. The wheel frame is connected between the wheel hub and the fan blade assembly, wherein the wheel frame and the multiple fan blades of the fan blade assembly are combined together with heterogeneous materials.

Based on the above, in the above embodiment of the present invention, the centrifugal heat dissipation fan has the characteristics of wheel blades far away from the hub by combining the wheel frame and the multiple blades of the fan blade assembly with heterogeneous materials. That is, under the structural support of the wheel frame, the thickness of these blades can be further reduced, and the number of blades can be relatively increased, so that the centrifugal fan can increase the airflow pressure at its exhaust point and improve the heat dissipation efficiency.

100: Centrifugal cooling fan

110, 120, 110A, 120A: fan blade assembly

130: wheel hub

140, 140A, 140C: wheel frame

141, 141A: first joint

142, 142A, 142C: Connection part

143, 143A: Second joint

143C: junction

150: Shell

151, 152: Air inlet

153, 154: Air outlet

A1, B1, A11: Top edge

A2, A4, B2, B4, A21, B21: Curved side edges

A3: Side edge

A5, B5, A51: bottom edge

B3, B61: inner edge

B6, B62: outer edge

C1~C7: junction

G1: Gap

L1, L2, L1a: radial dimensions

X1: Axial direction

X2: radial

Figure 1 is a schematic diagram of a centrifugal heat dissipation fan according to an embodiment of the present invention.

Figure 2 is a top view of some components of the centrifugal heat dissipation fan in Figure 1.

FIG3 is a partial cross-sectional view of the centrifugal heat dissipation fan of FIG1.

Figure 4 is a partial schematic diagram of a centrifugal heat dissipation fan of another embodiment of the present invention.

Figure 5 is a schematic diagram of the outer fan blades of another embodiment of the present invention.

Figure 6 is a schematic diagram of a centrifugal heat dissipation fan of another embodiment of the present invention.

Figure 7 is a top view of the centrifugal heat dissipation fan in Figure 6.

FIG8 is a cross-sectional view of the centrifugal heat dissipation fan of FIG6.

Figure 9 is a schematic diagram of the relevant components of the centrifugal heat dissipation fan of the present invention.

Fig. 1 is a schematic diagram of a centrifugal heat dissipation fan according to an embodiment of the present invention. Fig. 2 is a top view of some components of the centrifugal heat dissipation fan of Fig. 1. Fig. 3 is a partial cross-sectional view of the centrifugal heat dissipation fan of Fig. 1. Please refer to Figures 1 to 3 at the same time. In this embodiment, the centrifugal heat dissipation fan 100 includes a hub 130, a blade assembly 110 and a blade assembly 120, a wheel frame 140 and a housing 150, wherein the hub 130, the blade assembly 110, the blade assembly 120 and the wheel frame 140 are arranged in the housing 150 and rotate along the axial direction X1. At the same time, the housing 150 has two air inlets 151 and 152 located on the axial direction X1 and at least one air outlet located on the radial direction X2 (this embodiment shows two air outlets 153 and 154 as an example). When the centrifugal cooling fan 100 is running, the airflow enters the housing 150 from the air inlets 151 and 152, and flows out of the housing 150 from the air outlets 153 and 154.

More importantly, the double-layered blade assembly (blade assembly 110, 120) of the present embodiment surrounds the wheel hub 130 in the inner layer and the outer layer along the radial direction X2, wherein the gap G1 is maintained between the blade assembly 110 located in the inner layer and the blade assembly 120 located in the outer layer along the radial direction X2, and the wheel carrier 140 connects the wheel hub 130 and the blade assembly 120 located in the outer layer. Furthermore, the blade assembly 110 located in the inner layer is directly structurally coupled to the wheel hub 130, while the blade assembly 120 located in the outer layer is indirectly coupled to the wheel hub 130 via the wheel carrier 140. In short, the inner blade assembly 110 has wave blade characteristics, while the outer blade assembly 120 has wheel blade characteristics. The biggest difference between the two is whether the blades are directly connected to the wheel hub 130.

The fan blade assembly 110 and the wheel hub 130 are combined with heterogeneous materials, for example, the metal fan blade is combined with the plastic wheel hub 130 by means of embedded injection, or the plastic fan blade is integrally formed with the wheel hub 130, or the metal fan blade is combined with the metal wheel hub 130 by means of casting. In this way, the fan blade assembly 110 directly combined with the wheel hub 130 is located on the axis X1 corresponding to the air inlets 151 and 152, and serves as the main structure for introducing the air from the external environment into the housing 150 when the centrifugal heat dissipation fan 100 is running. The wave blade structure is adopted because it can increase the flow rate and smoothness of the airflow into the housing 150. In another embodiment not shown, the fan blade assembly and the wheel hub (or wheel frame) can also be made by means of integrated plastic molding, or the wheel hub is made of plastic and combined with metal (sheet metal or die-cast) fan blades, or the metal (die-cast) wheel hub and metal (sheet metal) fan blades are combined. For example, the fan blade assembly is stainless steel (SUS304) and the wheel frame is die-cast aluminum alloy (ADC6); or the fan blade assembly is stainless steel (SUS304) and the wheel frame is plastic (liquid crystal polymer, LCP).

Specifically, as shown in FIG. 3 , each of the multiple blades of the inner blade assembly 110 has arcuate side edges A2 and A4, and the notches of the arcuate side edges A2 and A4 face the air inlet 151 (axial direction X1) and the air outlets 153 and 154 (radial direction X2, shown in FIG. 1 ), so as to guide the airflow flowing into the centrifugal heat dissipation fan 100 from the air inlets 151 and 152 to the outer blade assembly 120.

As shown in Figure 3, each blade of the fan blade assembly 110 has a top edge A1 corresponding to the air inlet 151, a bottom edge A5 corresponding to the air inlet 152, and a side edge A3 corresponding to the air outlet 153 or 154 (radial X2), and the aforementioned arc-shaped side edge A2 is adjacent to the top edge A1 and the side edge A3, and the aforementioned arc-shaped side edge A4 is adjacent to the bottom edge A5 and the side edge A3, wherein the top edge A1 has a radial dimension L1, the bottom edge A5 has a radial dimension L2, and the side edge A3 has a radial dimension L1a, the radial dimension L1 is smaller than the radial dimension L1a, and the radial dimension L2 is smaller than the radial dimension L1a. Therefore, the radial size of each blade of the blade assembly 110 gradually increases from the air inlets 151, 152 (axial direction X1) toward the air outlets 153, 154 (radial direction X2), thereby providing the above-mentioned airflow guiding effect.

Here, from the perspective of the blades of the blade assembly 110, under the premise that the rotation speed of the hub 130 is fixed, the blades of the blade assembly 110 will have a larger tangential speed at the side edge A3, while the top edge A1 or the bottom edge A5 will have a smaller tangential speed due to the aforementioned size limitation and the arc-shaped side edges A2 and A4. In this way, the area with a fast tangential speed represents a smaller airflow pressure. Therefore, the blades of the blade assembly 110 can not only smoothly guide the airflow into the blade assembly 110 through the gradual expansion design of its radial size, but also increase the ability to absorb external air.

In contrast, each of the multiple blades of the outer blade assembly 120 has arc-shaped side edges B2 and B4, and the notches of the arc-shaped side edges B2 and B4 face the air inlets 151 and 152 (axial direction X1) and the hub 130, and are opposite to the arc-shaped side edges A2 and A4 of the aforementioned blade assembly 110, so that the outer blade assembly 120 can smoothly receive the airflow guided from the blade assembly 110. Furthermore, as shown in FIG. 3, the arc-shaped side edges A2, A4, B2, and B4 of this embodiment have different curvatures, which also means that the air inlets 151 and 152 of the housing 150 can also be designed with different sizes or shapes.

Please refer to FIG. 2 and FIG. 3 again. In this embodiment, the wheel frame 140 includes a first coupling portion 141, a connecting portion 142 and a second coupling portion 143. The first coupling portion 141 is coupled to the wheel hub 130, the second coupling portion 143 is coupled to the outer blade assembly 120, and the connecting portion 142 is connected between the first coupling portion 141 and the second coupling portion 143. Here, some blades of the inner blade assembly 110 are also coupled to the connecting portion 142. Because the blade assembly 120 uses the wheel frame 140 as the connection and support structure between it and the wheel hub 130, it is different from the blade assembly 110. The blade assembly 120 obviously has the characteristics of a wheel blade, that is, the wheel frame 140 is used as its supporting base. Therefore, for each blade of the blade assembly 120, the thickness can be further thinned without worrying about the influence of insufficient structural strength. This is also equivalent to increasing the number of blades of the blade assembly 120, and there is no need to worry about the aforementioned difficulty in assembly. For example, the thickness of each blade of the blade assembly 120 located on the outer layer can be less than or equal to 0.08mm, and due to the existence of the second joint 143, there is no need to worry about the lack of rigidity of the blade.

In short, the outer blade assembly 120 can be made of metal material so that the number of blades of the inner blade assembly 110 is less than or equal to the number of blades of the outer blade assembly 120, and the thickness of the blades of the outer blade assembly 120 is less than the thickness of the blades of the inner blade assembly 110. In this way, the thinner blade structure and the increase in the number of blades can effectively increase the airflow rate and airflow pressure of the outer blade assembly 120. In addition, the designer can also adjust the number of blades of the inner blade assembly 110 and the number of blades of the outer blade assembly 120 to adjust the noise generated by the centrifugal cooling fan 100 during operation. In other words, by using the different numbers of blades in the double-layered fan blade assemblies 110 and 120, the centrifugal cooling fan 100 can be prevented from continuously generating high-frequency or low-frequency noise.

Please refer to Figure 3 again. In this embodiment, each blade of the blade assembly 120 also has a top edge B1, a bottom edge B5, an inner edge B3 and an outer edge B6, wherein the inner edge B3 is opposite to the side edge A3 of the blade of the blade assembly 110 and maintains a gap G1, the top edge B1 corresponds to the air inlet 151, the bottom edge B5 corresponds to the air inlet 152, and the outer edge B6 is used to correspond to the air outlets 153 and 154. Each blade of the blade assembly 120 also has a plurality of cutout structures located at the outer edge B6, which are used to increase the airflow and increase the generation of turbulence when discharged from the air outlets 153 and 154, so as to reduce the noise generated at the air outlets 153 and 154.

FIG4 is a partial schematic diagram of a centrifugal heat dissipation fan of another embodiment of the present invention, showing a partial part of the centrifugal heat dissipation fan from a side view. Referring to FIG4 , in this embodiment, unlike the pair of arc-shaped side edges in the aforementioned embodiment, each blade of the blade assembly 110A of this embodiment only has an arc-shaped side edge A21 facing the air inlet 151 (axial direction X1) and the air outlets 154, 154 (radial direction X2), and the blade assembly 120A also only has an arc-shaped side edge B21 facing the air inlet 151 (axial direction X1) and the air outlets 153, 154 (radial direction X2). What remains unchanged is that the radial dimension of the fan blade assembly 110 still gradually increases from the air inlet 151 (axial direction X1) toward the air outlets 154, 154 (radial direction X2) so as to smoothly guide the airflow from the air inlet 151 to the fan blade assembly 120A. Here, the radial dimension of the fan blade assembly 110A at its top edge A11 is smaller than the radial dimension at its bottom edge A51.

FIG5 is a schematic diagram of the outer blade of another embodiment of the present invention. Please refer to FIG5 and compare it with FIG3. Unlike the aforementioned embodiment in which only the outer edge B6 has a cutout structure, the blade of the blade assembly 120B of this embodiment has a cutout structure at both the inner edge B61 and the outer edge B62, and in this embodiment, the number of cutouts at the outer edge B62 is greater than the number of cutouts at the inner edge B61.

Please refer to FIG. 3 again. In this embodiment, the wheel frame 140 and the outer layer of the fan blade assembly 120 are combined with heterogeneous materials, that is, the fan blades of the fan blade assembly 120 are made of metal material and combined with the wheel frame 140 by means of embedded injection molding, wherein part of the fan blades of the inner layer of the fan blade assembly 110 can also be combined with the connecting portion 142 or the first combining portion 141 of the wheel frame 140. Here, the second combining portion 143 is substantially combined with the center of the fan blade of the fan blade assembly 120, and particularly corresponds to the notch of the inner edge B3. Next, please refer to FIG. 4 . The wheel frame 140A of this embodiment also includes a first joint portion 141A, a second joint portion 143A and a connecting portion 142A. However, unlike the aforementioned embodiment, the wheel frame 140A is located opposite to the air inlet 151, so that the first joint portion 141A is joined to the bottom of the wheel hub 130, and the second joint portion 143A is joined to the bottom of the blade of the blade assembly 120A, so as to match the contour trend of the arc-shaped side edges A21 and B21.

FIG6 is a schematic diagram of a centrifugal heat dissipation fan of another embodiment of the present invention. FIG7 is a top view of the centrifugal heat dissipation fan of FIG6. FIG8 is a cross-sectional view of the centrifugal heat dissipation fan of FIG6, which is generated along the section line A-A shown in FIG7. Referring to FIG6 to FIG8, the fan blade structure of this embodiment is closer to that shown in FIG4, that is, the wheel frame 140C includes a connecting portion 142C and a coupling portion 143C, and the wheel frame 140C is substantially an integrally formed structure with the wheel hub 130, so that the connecting portion 142C extends from the wheel hub 130 along the radial direction X2 and is connected to the coupling portion 143C. The coupling portion 143C is, for example, a ring that is concentric with the hub 130 (same rotation center, i.e., axial direction X1), and is used to couple each blade of the blade assembly 120. More importantly, the blade assembly 120 of this embodiment is the blade assembly 120 located at the outer layer of the aforementioned embodiment, and the coupling portion 143C is coupled to the bottom of the blade assembly 120, so that each blade of the blade assembly 120 passes through the coupling portion 143C as its coupling and supporting structure.

FIG9 is a schematic diagram of the combination of the relevant components of the centrifugal heat dissipation fan of the present invention. Please refer to FIG9 , which shows possible combination points C1~C7 between the wheel frame and the fan blade assembly 120 located on the outer layer, that is, the wheel frame can be combined with at least one of the combination points C1~C7. The area of the combination points C1~C7 between the wheel frame and the fan blade is about 10%~20% of the overall area of the fan blade. In other words, the wheel frame can be combined with the required position according to the needs, and can also be combined with multiple combination points C1~C7 at the same time. Under the premise that the fan blade assembly 120 can use the wheel frame as its supporting structure and ensure the structural strength of the fan blade, the designer can determine the location of the aforementioned combination points C1~C7 according to the conditions of the fan blade (such as appearance, size and thickness). FIG9 only provides possible forms of connecting the wheel frame to the joints C1~C3, but is not limited to this. It should be noted that the more these joints C1~C7 occupy the fan blade surface area, the stronger the bonding force can be provided, but it will reduce the fan blade's ability to work on the air (the ability to drive air, reflected in the airflow rate and flow rate, etc.), so when the area of the joints C1~C7 is greater than 20% of the fan blade area, it will begin to significantly affect the fan blade's ability to work. On the other hand, if the joint area is too small (less than 10%), the fan blade will not be able to resist the centrifugal force generated during high-speed rotation and the reaction force when working on the air, resulting in unexpected deformation or even damage.

In summary, in the above-mentioned embodiment of the present invention, the centrifugal heat dissipation fan is provided with a double-layer blade assembly radially surrounding the hub in the inner and outer layers, and a gap is maintained radially between the inner blade assembly and the outer blade assembly, and the hub and the outer blade assembly are connected by a wheel frame. In this way, the double-layer blade assembly can form an inner blade assembly with wave blade characteristics and an outer blade assembly with wheel blade characteristics, and the centrifugal heat dissipation fan can have the advantages of both wave blades and wheel blades by the above-mentioned configuration.

That is to say, for the double-layer fan blade assembly, the inner fan blade assembly is directly combined with the wheel hub, so it can maintain the design logic of the existing metal fan blades, that is, maintain the smoothness of airflow into the centrifugal cooling fan, have a larger airflow rate and reduce noise. Furthermore, for the outer blade assembly, since there is a wheel frame as a combination and support structure, and in particular, the metal blades can be combined with plastic or metal heterogeneous materials to effectively improve the structural strength of the outer blade assembly, the designer can further reduce the thickness of the blades of the outer blade assembly, which is equivalent to increasing the number of blades of the outer blade assembly, and also enables the centrifugal fan to increase the airflow pressure at its exhaust point, thereby improving the heat dissipation efficiency. At the same time, the number of blades of the outer blade assembly can also be adjusted and designed according to the number of blades of the inner blade assembly, so as to facilitate noise control.

100: Centrifugal cooling fan

110, 120: fan blade assembly

130: wheel hub

140: Wheel frame

150: Shell

151: Air inlet

153, 154: Air outlet

G1: Gap

X1: Axial direction

X2: radial

Claims (15)

A centrifugal heat dissipation fan includes: a wheel hub; a wheel frame; and a fan blade assembly, which surrounds the wheel hub and keeps a distance from the wheel hub in the radial direction, and the wheel frame is connected between the wheel hub and the fan blade assembly, wherein the wheel frame and the multiple fan blades of the fan blade assembly are combined together with heterogeneous materials, wherein the wheel frame and each of the fan blades of the fan blade assembly have at least one joint, and the area of the joint accounts for 10% to 20% of the surface area of each of the fan blades. A centrifugal heat dissipation fan as described in claim 1, wherein the blades of the fan blade assembly are made of metal and the wheel frame is made of plastic. A centrifugal heat dissipation fan as described in claim 1, wherein the blades of the blade assembly and the wheel frame are die-cast together using different types of metals. A centrifugal heat dissipation fan as described in claim 1, wherein the wheel frame and each of the blades of the blade assembly have multiple joints, and the area of these joints accounts for 10% to 20% of the surface area of each of the blades. A centrifugal heat dissipation fan as described in claim 1, wherein the wheel frame and the wheel hub are an integrally formed structure. A centrifugal heat dissipation fan as described in claim 1, wherein the wheel frame has a ring concentric with the wheel hub, and the blades of the blade assembly are coupled to the ring. A centrifugal heat dissipation fan as described in claim 1, wherein each of the blades of the blade assembly has an outer edge facing away from the hub, and at least one notch structure located on the outer edge. A centrifugal heat dissipation fan as described in claim 1, wherein the thickness of each blade of the blade assembly is less than or equal to 0.08 mm. The centrifugal heat dissipation fan as described in claim 1 further includes another blade set, which is disposed around the wheel hub. In the radial direction, the other blade set and the blade set are arranged as inner and outer layers relative to the wheel hub. As described in claim 9, the centrifugal heat dissipation fan, the other blade assembly includes a plurality of other blades, and the size of the other blade along the radial direction gradually increases as it moves away from the air inlet. As described in claim 9, the centrifugal cooling fan, the other blade assembly includes a plurality of other blades, and the radial dimension of the other blade gradually increases or decreases from the air inlet toward the other air inlet. A centrifugal heat dissipation fan includes: a hub; a wheel frame; and a blade assembly, which surrounds the hub and keeps a distance from the hub in the radial direction, and the wheel frame is connected between the hub and the blade assembly, wherein the wheel frame and the blade assembly are combined with heterogeneous materials, and each of the blades has at least one arc-shaped side edge, and the notch of the arc-shaped side edge faces the air inlet and the hub. The centrifugal heat dissipation fan as described in claim 12 further includes another blade group, which is disposed around the hub. In the radial direction, the other blade group and the blade group are arranged in an inner layer and an outer layer relative to the hub. The other blade group includes a plurality of other blades, and each of the other blades has at least one other curved side edge, which is opposite to the curved side edge of the blade, and the notch of the other curved side edge faces the air inlet and the air outlet. A centrifugal heat dissipation fan as described in claim 13, wherein the dimension of the other blade along the radial direction gradually increases as it moves away from the air inlet. A centrifugal heat dissipation fan as described in claim 13, wherein the radial dimension of the other blade gradually increases or decreases from the air inlet toward the other air inlet.

Images