CN203906325U - Centrifugal fan - Google Patents

Abstract

The utility model provides a centrifugal fan, comprising a fan frame and an impeller accommodated in the fan frame, wherein the fan frame has at least one air inlet and at least one air outlet respectively arranged on one side and the other side of the fan frame, and the impeller has a hub, an extension portion extending outward from the hub, and a plurality of blades arranged on the extension portion, wherein the rear ends of the blades are jointly wound around a virtual geometric contour and define a guide space relative to the hub, and the width of the guide space is greater than or equal to a chord length of the blade; through the centrifugal fan design of the utility model, it is possible to effectively achieve thinness and improve fan performance.

Description

centrifugal fan

【Technical field】

The utility model relates to a centrifugal fan, in particular to a centrifugal fan which has the effect of reducing the overall thickness of the centrifugal fan to meet the thinning design requirements and improving the performance of the fan, and also has the function of reducing noise. the

【Background technique】

Due to the gradual thinning of electronic devices (such as notebook computers or tablet computers), the internal space of electronic devices is extremely limited, so the cooling fan installed in it is required to be thinner, so its thickness must be reduced, and the cooling fan and adjacent The space between the components is also quite limited, resulting in poor cooling effect of the cooling fan. In particular, in the case of limited space, the airflow of the cooling fan cannot be evenly sent out from the air outlet of the cooling fan, thus affecting the cooling efficiency. the

China Taiwan Patent Publication No. 201303165 discloses a centrifugal fan, which is provided with a plurality of blades on the top surface of the hub, and the second ends of the blades jointly form a virtual geometric contour; wherein the virtual geometric contour has A maximum outer diameter, there is a distance between the second ends of any two adjacent blades of the fan wheel, the distance is smaller than the maximum outer diameter of the virtual geometric outline, so as to improve the heat dissipation effect. the

Although the above-mentioned conventional centrifugal fan can achieve improved heat dissipation effect, it extends another problem, because the blades are arranged on the top surface of the hub, so that its axial height is higher than that of the hub of the conventional conventional centrifugal fan. In other words, the original height of the hub plus the height of the blades will cause the overall axial height of the fan wheel to increase significantly, which in turn will cause the overall height of the fan frame that accommodates the fan wheel to also increase accordingly. As seen in Figure 4 of Publication No. 201303165, the overall axial height of the fan frame is the axial height of the side wall plus the axial height of the side air outlet or air inlet, and the axial height of the opposite fan frame The height is also the overall height of the fan wheel, so the overall thinning of the conventional centrifugal fan is quite limited and the thickness cannot be saved, which in turn also results in the height limitation of the internal space of the electronic device, so that the centrifugal fan cannot be installed in the Therefore, the industry is still unable to overcome the problem of how to achieve thinning and improve the performance of the fan at the same time. the

Therefore, how to solve the above-mentioned common problems and deficiencies is the direction that the utility modeler of this case and the relevant manufacturers engaged in this industry want to study and improve. the

【Content of utility model】

Therefore, in order to effectively solve the above problems, the main purpose of this utility model is to provide a centrifugal fan that can reduce the overall thickness of the centrifugal fan to achieve thinning and improve the performance of the fan. the

To achieve the above purpose, the utility model provides a centrifugal fan, including: a fan frame, the upper side and the lower side are closed and there is an accommodating space therein, the fan frame has at least one air inlet and at least one outlet The air inlet, the air inlet and the air outlet are connected to the accommodation space, and they are respectively opened on one side and the other side of the fan frame; and an impeller is accommodated in the accommodation space, and it has a plurality of blade, an extension part and a hub, the extension part is formed by extending outward from the outer peripheral side of the hub, and the blade is arranged in a direction away from the hub, and the blade is provided with a front end and a rear end, so A guide space is defined between a virtual geometric contour defined by the rear end and the hub, and there is a chord length between the front end and the rear end of the blade, and the width of the guide space is greater than or equal to the Describe the chord length of the blade. the

The fan frame includes a cover plate, a bottom plate, a tongue guard and a side plate, the side plate is formed by extending upward from the periphery of the bottom plate, and is provided with a first side wall, a second side wall, and a third side wall and a fourth side wall, the air inlet and the air outlet are opened on the first and second side walls respectively, and the cover plate is set on the end opposite to the side plate, and jointly defined with the bottom plate and the side plate The accommodating space, the tongue part protrudes from the position where the first side wall and the second side wall are in contact with each other into the accommodating space, and is adjacent to the front end of the blade. the

The third and fourth side walls are adjacent to each other and form a first straight section, a second straight section, a curved section and an expanded curved section on the inner side, and the first straight section is located adjacent to the air inlet One side of the curved section is connected to the first straight section, and the other side is connected to one side of the opposite expanded curved section. The second straight section is located adjacent to the air outlet, and its connection Opposite the other side of the expanded curved section. the

A flow channel is defined between the front end of the blade and the opposite third and fourth side walls, the width of the flow channel gradually expands from the curved section to the expanded curved section, and the flow channel includes a relatively narrow width of the flow channel A high wind pressure area and a low wind pressure area with a relatively wide channel width. the

The blades define a guide channel communicating with the flow channel and the guide space, the extension part has a plurality of extension arms, and the extension arms extend outward from the outer peripheral side of the hub to form a free end, The free ends are connected to form a ring body, the blade ring is arranged on the ring body, and the extension arms define a separate space communicating with the flow guiding space. the

The angle between the air outlet and the air inlet is between 30 degrees and 90 degrees. the

The extension part has a plurality of extension arms, and the extension arms extend outward from the outer peripheral side of the hub to form a free end, and the free ends are connected to each other to form a ring body, and a part of the plurality of blade rings is arranged on the hub. On an upper end surface of the ring body, another part of the plurality of blades is arranged around the lower end surface of the ring body, and is interlaced with the aforementioned part of the plurality of blades. the

Through the design of the centrifugal fan of the present invention, it is possible to effectively achieve the effect of thinning and effectively improving the performance of the fan. the

【Description of drawings】

1 shows a schematic exploded view of the first preferred embodiment of the utility model. the

2 shows the combined schematic view of the first preferred embodiment of the utility model. the

3 shows a schematic top view of the first preferred embodiment of the utility model. the

4A shows another schematic top view of the first preferred embodiment of the present invention. the

4B shows another schematic top view of the first preferred embodiment of the present invention. the

4C shows another schematic top view of the first preferred embodiment of the present invention. the

5A shows the noise spectrum diagram of the centrifugal fan of the first preferred embodiment of the present invention. the

5B shows the projection ratio spectrum diagram of the centrifugal fan in the first preferred embodiment of the present invention. the

6A shows the noise spectrogram of the centrifugal fan. the

6B shows the prominence ratio spectrogram of the centrifugal fan. the

7 shows another exploded view of the first preferred embodiment of the utility model. the

8A shows an exploded view of the second preferred embodiment of the present invention. the

8B shows another exploded view of the second preferred embodiment of the present invention. the

The component names corresponding to the reference signs in the figure are:

Centrifugal fan…1

Fan frame...11

Cover...111

Bottom plate…112

Shaft seat...1121

Tongue...113

Side panels…114

First side wall...1141

Second side wall...1142

Third side wall...1143

Fourth side wall...1144

The first straight section...1151

The second straight section...1152

Bending section...1153

Expansion bending section...1156

Runner...116

High wind pressure area...1161

Low wind pressure area...1162

Accommodating space...117

Air inlet...118

Air outlet...119

Impeller…13

Blades…131

Front end...1311

Backend...1312

Chord length...1313

Virtual geometric outline... 1314

Diversion channel...132

Extension...133

Extension arm...1331

Free end...13311

Ring…134

Space apart... 135

Hub…136

Diversion space...137

Width of diversion space…W

【Detailed ways】

The above-mentioned purpose of the utility model and its structural and functional characteristics will be described according to the preferred embodiments of the accompanying drawings. the

The utility model provides a centrifugal fan, as shown in Figures 1 and 2, showing a schematic diagram of the decomposition and assembly of the first preferred embodiment of the utility model, and supplemented by Figure 3; the centrifugal fan 1 is applied and installed in In an electronic device (such as a notebook computer, a tablet computer, an IPAD, a portable wearable device; not shown in the figure), and the centrifugal fan 1 includes a fan frame 11 and an impeller 13, the upper side of the fan frame 11 It is closed with the lower side and has an accommodating space 117 therein, and the fan frame 11 includes at least one air inlet 118, at least one air outlet 119, a cover plate 111, a bottom plate 112, a tongue 113 and a Side plate 114, the air inlet 118 communicates with the air outlet 119 relative to the accommodating space 117, and it is respectively opened on one side and the other side (ie the adjacent side) of the fan frame 11, that is, the The air inlet 118 and the air outlet 119 are provided on the first and second side walls 1141, 1142 of the aforementioned side plate 114 respectively, and the cover plate 111 communicates with the accommodating space 117 defined jointly by the bottom plate 112 and the side plate 114. The aforementioned air inlet 118 and air outlet 119 . And the aforementioned side plate 114 extends upwards from the periphery of the bottom plate 112, and one end (that is, the end of the side plate 114 opposite to the bottom plate 112) is covered with a corresponding cover plate 111; in the side plate 114 of this preferred embodiment It is integrally formed with the bottom plate 112 for illustration. Wherein the bottom plate 112 and the cover plate 111 are closed without any holes. the

There is a shaft seat 1121 on the aforementioned bottom plate 112, and the shaft seat 1121 is accommodated at the center of the accommodating space 117, that is, the shaft seat 1121 protrudes axially from the center of the bottom plate 112 in the accommodating space 117. Composed, and pivotally arranged with the opposite impeller 13. The aforementioned side plate 114 has the aforementioned first side wall 1141, the aforementioned second side wall 1142, a third side wall 1143 and a fourth side wall 1144, and the first and second side walls 1141, 1142 are used in this preferred embodiment The first side wall 1141 is perpendicular to the second side wall 1142 for illustration; Adjacent to the impeller 13, the tongue portion 113 is used to prevent (or block) the airflow from the air outlet 119 from flowing back and leaking out from the air inlet 118, thereby reducing the mutual interference between the airflow entering from the air inlet 118 and the airflow flowing out from the air outlet 119 , and then can make the air inlet 118 easier to inhale, and at the same time improve the utilization efficiency of the air intake of the centrifugal fan 1, so as to achieve the effects of reducing noise and increasing air volume and wind pressure. the

And the aforementioned air outlet 119 is located between the tongue 113 and the fourth side plate 114, and it is opposite to the third side wall 1143, and the air inlet 118 is located between the tongue 113 and the third side wall 1143, And it is opposite to the fourth side wall 1144 . Wherein the angle between the air outlet 119 and the air inlet 118 is between 30 degrees and 90 degrees, and the angle is based on the axis of the hub 136, so as to face the air outlet 119 and the air inlet 118 relative to each other. The angle defined between the dotted lines extending outward in the direction, and the angle between the air outlet 119 and the air inlet 118 in this preferred embodiment is preferably 90 degrees for illustration, but it is not limited thereto. During specific implementation, the user can design and adjust the angle between the air outlet 119 and the air inlet 118 to be 30 degrees (as shown in FIG. The angle between the air outlet 119 and the air inlet 118 is 45 degrees (as shown in FIG. 4B ), or the angle between the air outlet 119 and the air inlet 118 is 60 degrees (as shown in FIG. 4A ). Chen Ming. the

As shown in Figures 1 and 3, the third and fourth sidewalls 1143, 1144 are adjacent to each other and form a first straight section 1151, a second straight section 1152, a curved section 1153 and an expansion curve. Section 1156, the first straight section 1151 is located adjacent to the entrance, one side of the curved section 1153 is connected to the opposite first straight section 1151, and the other side is connected to one side of the opposite expansion curved section 1156 , the second straight section 1152 is located adjacent to the air outlet 119, and it is connected to the opposite side of the expanded curved section 1156. The inner sides of the three sidewalls 1143 extend toward the air outlet 119 , and sequentially connect the curved section 1153 , the expanded curved section 1156 to the second straight section 1152 inside the fourth sidewall 1144 adjacent to the air outlet 119 . the

The aforementioned impeller 13 is accommodated in the accommodating space 117, and it has a plurality of blades 131, an extension 133 and a hub 136, the extension 133 is formed by extending outward from the outer peripheral side of the hub 136, and it is away from The blades 131 are arranged in the direction of the hub 136; and the aforementioned extension 133 has a plurality of extension arms 1331, and the extension arms 1331 extend outward from the outer peripheral side of the hub 136 and form a free end 13311, the free end 13311 They are connected with each other to form a ring body 134, the blades 131 are arranged on the ring body 134, and define a guide channel 132 between them, and the extension arms 1331 define a communication space between them. 117 separated space 135. Wherein the above-mentioned extension part 133 can be redesigned as a ring-shaped extension arm 1331 during specific implementation, as also shown in Figure 7, the extension arm 1331 extends outward along the outer peripheral side of the hub 136 to form the ring The disc-shaped extension arm 1331 , and the vane 131 is arranged around the peripheral end of the disc-shaped extension arm 1331 away from the hub 136 . the

The blade 131 is provided with a front end 1311 and a rear end 1312, the front end 1311 of the blade 131 protrudes outside an outer periphery of the ring body 134, and the rear end 1312 of the blade 131 is connected with the ring in this preferred embodiment The inner peripheral side of the body 134 is tangent to the outer peripheral side of the hub 136, but it is not limited to this. When the utility model is actually implemented, the rear end 1312 of the blade 131 can also be designed to protrude from the ring. Body 134 is outwardly opposed to an inner periphery of hub 136 . And the rear end 1312 of the blade 131 is jointly circled to define a virtual geometric contour 1314, and a flow guiding space 137 connecting the accommodating space 117 and the flow guiding channel 132 is defined between the virtual geometric contour 1314 and the hub 136 There is a chord length 1313 between the front end 1311 and the rear end 1312 of the aforementioned blade 131, and the width W of the flow guide space 137 is greater than or equal to the chord length 1313 of the blade 131, for example, the width of the flow guide space 137 It is 1.5 centimeters (cm) greater than the chord length 1313 of the blade 131 which is 1.1 centimeters (cm), or the width of the diversion space 137 is 1.1 centimeters which is equal to the chord length 1313 of the blade 131 being 1.1 centimeters. the

Therefore, through the structural design in which the width W of the guide space 137 is greater than or equal to the chord length 1313 of the plurality of blades 131, the external airflow is effectively introduced into the fan frame 11 from the air inlet 118 in a radial direction. , so that the air flow will be pressurized by the blades 131 and enter the flow guide space 137 of the accommodating space 117, and then pass through the plurality of blades 131 of the impeller 13 to make the air flow radially toward the opposite air outlet 119 is exported to the outside, so as to effectively and greatly improve the performance of the fan. In addition, through the structural design of the plurality of blades 131 of the present invention and the arrangement in the radial direction (or horizontal direction) corresponding to the hub 136, the axial height of the hub 136 can be reduced (or reduced), and the relative fan frame The overall axial height of 11 is also reduced accordingly, thus effectively achieving the effects of thickness saving and thinning of the centrifugal fan 1 . the

As shown in Figures 1 to 3, the front end 1311 of the plurality of blades 131 is adjacent to the corresponding tongue portion 113, and it defines a flow channel communicating with the guide channel 132 with the third and fourth side walls 1143, 1144. 116, the width of the flow channel 116 gradually expands from the bending section 1153 to the expansion bending section 1156, and the aforementioned flow channel 116 includes a high wind pressure area 1161 with a relatively narrow width of the flow channel 116 and a relatively wide area with a relatively wide width of the flow channel 116 Low wind pressure zone 1162, the high wind pressure zone 1161 is located at the first straight section 1151 adjacent to the curved section 1153, and the low wind pressure zone 1162 is located at the curved section 1153, the expansion curved section 1156 and the outlet At the tuyere 119, so when the impeller 13 of the centrifugal fan 1 is running, the blades 131 of the impeller 13 will introduce the external airflow from the aforementioned air inlet 118 into the fan frame 11 in a radial direction, so that the airflow will be affected by the blades. 131 is pressurized to enter the air guiding space 137 from the air guiding channel 132, part of the air flow to the first straight section 1151 will be blocked by the high flow resistance of the high wind pressure area 1161, and will be blocked by said The vanes 131 are guided into the guide space 137 (that is, guided into the low-pressure guide space 137 by the vanes 131), and then pressurized again by the vanes 131 of the impeller 13, so that a part of the air flow will be passed by the guide space 137. The guide channel 132 is smoothly guided into the flow channel 116 of the bending section 1153 and the expansion bending section 1156 of the low wind pressure area 1162, and when the air flow flows into the flow channel 116 of the expansion bending section 1156, it will be expanded by the expansion. The curved section 1156 is pressurized, and is exported from the second straight section 1152 to the air outlet 119 in a radial direction, and then another part of the airflow is directly exported to the outside by the guide channel 132 toward the relative air outlet 119, so that It can effectively achieve the effect of improving the performance of the fan and saving the thickness. the

Therefore, the air inlet 118 and the air outlet 119 are provided on both sides of the fan frame 11 of the present utility model, and the width of the flow guide space 137 is greater than or equal to the structural design of the chord length 1313 of the blade 131, which can effectively achieve The effect of reducing noise and saving thickness, and effectively improving the performance of the fan. the

As shown in Figures 5A to 6B, the noise test comparison charts of the centrifugal fan 1 of the present invention and the conventional centrifugal fan are shown; Figures 6A and 6B show the noise spectrum of the conventional centrifugal fan and the outstanding performance of the conventional centrifugal fan Compared with the spectrum diagram, it can be found from FIG. 6A that the conventional centrifugal fan will produce a higher blade frequency peak P1 in the noise spectrum diagram at a certain blade speed, and the blade frequency peak P1 is about 29 decibels ( dB). As shown in FIG. 6B, it can be found that corresponding to the fan blade frequency peak P1 in FIG. 6A, a relatively high prominence ratio can be found, and the ratio of the prominence ratio (Prominence Ratio) is close to 7dB (decibel). the

And Fig. 5 A, 5B are the noise spectrogram of the centrifugal fan 1 of the present utility model and the prominent ratio spectrogram of centrifugal fan 1, can find thus, the fan blade frequency peak value of the centrifugal fan 1 of this preferred embodiment in Fig. 5 A is about It is 19 decibels (dB), and as shown in Figure 5B corresponding to the fan blade noise peak in Figure 5A, a relatively high prominence ratio can be found, and the ratio of the prominence ratio (Prominence Ratio) is close to 5dB (decibel); In addition, when the protrusion rate ratio exceeds 6dB, it is judged that the noise has a prominent "abnormal sound". Therefore, after the above analysis, it can be seen that the noise of the centrifugal fan 1 of the present utility model is significantly lower than that of the conventional centrifugal fan 1, so the present utility model The design of the novel centrifugal fan 1 can effectively reduce noise. the

As shown in Fig. 8A, 8B, show the exploded schematic view of the second preferred embodiment of the present utility model; The structure of this preferred embodiment and connection and its effect are roughly the same as the aforementioned first preferred embodiment, so here No need to go into details again; this preferred embodiment is mainly to change the plurality of blades 131 of the aforementioned first preferred embodiment into a staggered arrangement of the plurality of blades 131 on the ring body 134, that is, a part of the plurality of blades 131 The ring is arranged on an upper end surface of the ring body 134, and another part of the plural blades 131 is arranged on the lower end surface of the ring body 134, and it and the aforementioned part of the plurality of blades 131 are arranged in a staggered arrangement. the

Therefore, through the design that the part of the plurality of blades 131 and the other part of the plurality of blades 131 are respectively arranged on the upper end surface and the lower end surface of the ring body 134 and interlaced with each other, the effect of reducing fan noise can be effectively achieved. the

As mentioned above, the utility model has the following advantages compared to the prior art:

1. It has the effect of saving thickness. the

2. It has the effect of improving the performance of the centrifugal fan. the

3. It has the effect of reducing noise. the

But what is described above is only a preferred embodiment of the utility model, and all changes made by using the above-mentioned method, shape, structure, and device of the utility model should be included in the scope of rights of the present case. the

Claims (7)

1. A centrifugal fan, characterized in that, comprising: The fan frame, the upper side and the lower side of which are closed and has an accommodating space therein, the fan frame has at least one air inlet and at least one air outlet, the air inlet and the air outlet communicate with the accommodating space, and its on one side and the other side of the frame respectively; and An impeller is accommodated in the accommodating space, and it has a plurality of blades, an extension part and a hub, and the extension part is formed by extending outward from the outer peripheral side of the hub, and it is away from the direction of the hub These blades are arranged on the blade, and the blade is provided with a front end and a rear end, and the rear end jointly surrounds a defined virtual geometric contour and defines a guide space between the hub, and the front end of the blade and the There is a chord length between the rear ends, and the width of the guide space is greater than or equal to the chord length of the blades. the 2. The centrifugal fan according to claim 1, wherein the fan frame comprises a cover plate, a bottom plate, a tongue and a side plate, and the side plate extends upward from the periphery of the bottom plate, and It is provided with a first side wall, a second side wall, a third side wall and a fourth side wall, the air inlet and the air outlet are opened on the first and second side walls respectively, and the cover plate covers It is arranged on one end opposite to the side plate, and defines the accommodating space together with the bottom plate and the side plate, and the tongue part protrudes from the position where the first and second side walls contact each other toward the opposite accommodating space, And adjacently corresponding to the front ends of the equal blades. the 3. The centrifugal fan according to claim 2, wherein the third and fourth side walls are adjacent to each other and form a first straight section, a second straight section, a curved section and a An expanded curved section, the first straight section is located adjacent to the air inlet, one side of the curved section is connected to the first straight section, and the other side is connected to one side of the opposite expanded curved section , the second straight section is located adjacent to the air outlet, and is connected to the opposite side of the expanded curved section. the 4. The centrifugal fan according to claim 3, characterized in that, a flow channel is defined between the front end of the blade and the opposite third and fourth side walls, and the width of the flow channel is from the curved section to the expansion bend The section gradually expands, and the flow channel includes a high wind pressure area with a relatively narrow flow channel width and a low wind pressure area with a relatively wide flow channel width. the 5. The centrifugal fan according to claim 4, wherein the blades define a guide passage connecting the flow channel and the guide space, the extension part has a plurality of extension arms, and the extension arms extend from the hub The outer peripheral side extends outward and forms a free end, the free ends are connected to form a ring body, the blade ring is arranged on the ring body, and the extending arms define a gap communicating with the diversion space space. the 6. The centrifugal fan according to any one of claims 1-5, characterized in that, the angle between the air outlet and the air inlet is between 30 degrees and 90 degrees. the 7. The centrifugal fan according to claim 1, wherein the extension part has a plurality of extension arms, the extension arms extend outward from the outer peripheral side of the hub and form a free end, and the free ends are opposite to each other connected to form a ring body, and a part of the plurality of blades is arranged on an upper end surface of the ring body, and another part of the plurality of blades is arranged on the lower end surface of the ring body, and it is interlaced with the aforementioned part of the plurality of blades set up. the