CN2755321Y

CN2755321Y - Centrifugal fan

Info

Publication number: CN2755321Y
Application number: CN 200420104995
Authority: CN
Inventors: 高平生; 简灿男; 刘昱; 黄玉年
Original assignee: Quanta Computer Inc
Current assignee: Quanta Computer Inc
Priority date: 2004-11-22
Filing date: 2004-11-22
Publication date: 2006-02-01
Anticipated expiration: 2014-11-22

Abstract

A centrifugal fan is adapted for portable electronic devices. The eddy-shaped lateral plate of the casing of the centrifugal fan is tongue-and-mouth shaped. The tongue-and-mouth shaped part of the eddy-shaped lateral plate forms at least one concave groove which extends in approximately horizontal direction. Consequently, when the wake flow produced by the rotation of the air wing knocks the surface of the tongue-and-mouth shaped part of the eddy-shaped lateral plate, the noise of the centrifugal fan is decreased.

Description

Centrifugal fan

Technical field

The utility model relates to a kind of centrifugal fan (Centrifugal Fan), and the surface that particularly relates to the whirlpool type side plate at a kind of tongue degree of lip-rounding shape place forms the centrifugal fan of at least one groove that roughly extends in horizontal direction.

Background technique

Generally speaking, portable electronic device, especially mobile computer (Note Book PersonalComputer) in order to bring into play maximum usefulness, need radiating module and carry out efficiently radiates heat.If heat accumulation can't dissipate in real time at device interior the time, will make the electrical assembly can't proper functioning, even make entire equipment work undesired, especially therefore computer system more can crash.Yet mobile computer is for the market demand in response to mobile, and casing inside can't reserve enough natural convection spaces.Because HFS has faced suitable bottleneck on the execution heat dissipation design, so the radiating module of mobile computer dispels the heat towards producing forced convection with centrifugal fan gradually.

Please refer to Fig. 1, it illustrates the three-dimensional structure diagram of existing centrifugal fan.This centrifugal fan 10 is applicable to portable electronic devices, mobile computer for example, and this centrifugal fan 10 comprises at least: housing 11 and fan blade 31.Housing 11 has whirlpool type side plate 13 and base plate 15, and housing 11 limits cavity 17 and exhaust outlet 19, wherein cavity 17 and the exhaust outlet 19 common whirlpool type runners 21 that form, and the whirlpool type side plate 13 of a side at exhaust outlet 19 places then forms a tongue degree of lip-rounding shape 23.Fan blade 31 is to be located on the base plate 15 of cavity 17 with a vertical shaft 33.When fan blade 31 was rotated, the substantially horizontal air-flow 25 that fan blade 31 is driven produced dynamic pressures and static pressure and air-flow 25 is sent via whirlpool type runner 21.

Existing exhaust outlet 19 places utilize the curve surface gradual-enlargement pipeline of constant cross-section, the surface 16 that is the whirlpool type side plate 13 at tongue degree of lip-rounding shape 23 places is parallel to axle 33, make gas flow and produce dynamic pressure and static pressure, gas just has enough dynamic pressures and static pressure to resist external drag, reach the effect of heat radiation, shown in Figure 1A.

Please refer to Fig. 2, its wake flow impact that illustrates existing centrifugal fan generation is in the schematic representation of the whirlpool type side plate at tongue degree of lip-rounding shape place.During the surface 16 of the whirlpool type side plate 13 at wake flow (Wake Flow) 35 bump tongue degree of lip-rounding shapes 23 places that fan blade 31 produces, each shock point 41 can be considered the pronunciation source that produces narrow frequency noise (Narrow BandNoise) 43, because the surface 16 of the whirlpool type side plate 13 at tongue degree of lip-rounding shape 23 places is parallel to axle 33, according to the superposition principle of ripple, generation had the flabellum fundamental frequency noise (B1adePassFrequency) 43 of large amplitude 45 and fixed frequency.In case need to improve heat dissipation, certainly will to increase air quantity and wind speed, yet when rotating speed increases and improve flow, but obtain the noise spectrum of higher frequency, make level of noise high more.

In view of above-mentioned, need the whirlpool type side plate that improves tongue degree of lip-rounding shape place badly, to solve the noise problem that centrifugal fan causes.

The model utility content

One of the purpose of this utility model is exactly to disclose a kind of centrifugal fan, be applicable to portable electronic devices, the whirlpool type side plate of this centrifugal fan housing becomes tongue degree of lip-rounding shape, and the surface of the whirlpool type side plate at tongue degree of lip-rounding shape place forms at least one groove that roughly extends in horizontal direction, therefore when the whirlpool type side plate at the wake flow impact tongue degree of lip-rounding shape place that the fan blade rotation is produced surperficial, can reduce the noise of fan.

The purpose above-mentioned according to the utility model, a kind of centrifugal fan is proposed, this centrifugal fan is applicable to portable electronic devices, and this centrifugal fan comprises at least: a housing, this housing has base plate and whirlpool type side plate, whirlpool type side plate is arranged on the base plate and limits cavity and exhaust outlet, and becomes tongue degree of lip-rounding shape at the whirlpool type side plate of at least one side of this exhaust outlet; And fan blade, fan blade is to be located on the base plate of cavity; Wherein form at least one groove that roughly extends in horizontal direction on the whirlpool type side plate at tongue degree of lip-rounding shape place.

According to the utility model one preferred embodiment, above-mentioned portable electronic devices is a mobile computer.

According to the utility model one preferred embodiment, the surface of the whirlpool type side plate at above-mentioned tongue degree of lip-rounding shape place can have one or more groove that roughly extends in horizontal direction.

Centrifugal fan of the present utility model forms at least one groove that roughly extends in horizontal direction in the surface of the whirlpool type side plate at tongue degree of lip-rounding shape place, and is not only easily manufactured, more improves the noise problem that centrifugal fan causes.

Description of drawings

Fig. 1 is the three-dimensional structure diagram of existing centrifugal fan;

Figure 1A is the substantially horizontal air-flow that is produced behind the drive fan blade in the centrifugal fan;

Fig. 2 is that the wake flow impact that produces of existing centrifugal fan is in the schematic representation of the whirlpool type side plate at tongue degree of lip-rounding shape place;

Fig. 3 is the three-dimensional structure diagram of the centrifugal fan of the utility model one preferred embodiment;

Fig. 4 is that the wake flow impact that produces of the centrifugal fan of the utility model one preferred embodiment is in the schematic representation of the whirlpool type side plate at tongue degree of lip-rounding shape place;

Fig. 4 A is the position view of the groove of the utility model one preferred embodiment with respect to fan blade;

Fig. 5 is the surface of side plate sectional schematic diagram of another preferred embodiment of the utility model;

Fig. 6 is the surface of side plate sectional schematic diagram of the another preferred embodiment of the utility model;

Fig. 7 A is that the She Kou of centrifugal fan does not form the flat spectrogram of reeded wind; And

Fig. 7 B is the flat spectrogram of wind that the snake interruption-forming of centrifugal fan has a groove.

Embodiment

Please refer to Fig. 3, it illustrates the three-dimensional structure diagram according to the centrifugal fan of the utility model one preferred embodiment.This centrifugal fan 100 is applicable to portable electronic devices, mobile computer for example, and this centrifugal fan 100 comprises at least: a housing 111 and fan blade 131.Housing 111 has whirlpool type side plate 113 and base plate 115, and housing 111 limits cavity 117 and exhaust outlet 119, wherein cavity 117 forms whirlpool type runners 121 jointly with exhaust outlet 119, and the whirlpool type side plate 113 of at least one side of exhaust outlet 119 then forms a tongue degree of lip-rounding shape 123.Fan blade 131 is by on one 133 base plate 115 that is set up in cavity 117, and axle 133 is being preferable perpendicular to base plate 115.When fan blade 131 was rotated, the substantially horizontal air-flow 125 that fan blade 131 is driven produced dynamic pressures and static pressure and air-flow 125 is sent via whirlpool type runner 121.Simultaneously, when fan blade 131 is rotated the surface 116 of whirlpool type side plate 113 at wake flow 135 bump tongue degree of lip-rounding shapes 123 places that produced, tongue degree of lip-rounding shape of the present utility model 123 places utilize the horizontal-extending groove 118 that is formed at side plate 113 surfaces 116, destroy the ripple superposition phenomenon that wake flow 135 is caused on the surface 116 of the whirlpool type side plate 113 at tongue degree of lip-rounding shape 123 places, thereby can reduce noise.According to the utility model, groove 118 can pass through modes such as injection molding, metal casting or metal stamping, is shaped on the housing 111.

Please refer to Fig. 4, it illustrates the wake flow impact that produces according to the centrifugal fan of the utility model one preferred embodiment in the schematic representation of the whirlpool type side plate at tongue degree of lip-rounding shape place.During the surface 116 of the whirlpool type side plate 113 at wake flow 135 bump tongue degree of lip-rounding shapes 123 places that fan blade 131 produces, each shock point 141 can be considered the pronunciation source that produces flabellum fundamental frequency noise 143, owing to form a horizontal-extending groove 118 on the surface 116, make the asynchronism(-nization) that each pronunciation source produces, so the pronunciation sound wave that cause in the source of different time domain can overlap each other, make amplitude 145 to reduce significantly, promptly the intensity of flabellum fundamental frequency noise 143 reduces.

According to the utility model, a part that is formed at the horizontal-extending groove 118 on the surface 116 is the zone of flowing through corresponding to the wake flow 135 of fan blade 131.For example, with reference to Fig. 4 A, formed groove 118 is the neutral positions in the face of fan blade 131 short transverses on the surface 116 of the whirlpool type side plate 113 at tongue degree of lip-rounding shape of the present utility model 123 places, it also can be designed to certainly in the face of the relative upside of fan blade 131 short transverses or relative upside, as long as the zone that the part of groove 118 is flowed through corresponding to the wake flow 135 of fan blade 131.In addition, the surface 116 of the whirlpool type side plate 113 at tongue degree of lip-rounding shape of the present utility model 123 places also can form two or three grooves 118 that roughly extend in horizontal direction.Illustrated in Fig. 3, it promptly illustrates the three-dimensional structure diagram according to the centrifugal fan of the utility model one preferred embodiment, and wherein surface 116 is provided with a horizontal-extending groove 118, and this groove has a rectangular section.

Please refer to Fig. 5, it illustrates the three-dimensional structure diagram according to the centrifugal fan of another preferred embodiment of the utility model, wherein then forms the groove 118 of two rectangular sections on the surface 116.Please refer to Fig. 6, it illustrates the three-dimensional structure diagram according to the centrifugal fan of the another preferred embodiment of the utility model, wherein forms a groove 118a with arc-shaped sections on the surface 116.Yet the utility model is not limited to above-mentioned groove quantity or section configuration, anyly be familiar with this operator and can utilize alternate manner when understanding, and look actual demand and adjust the utility model groove quantity or section configuration, or several grooves of combination different section shape are to constitute the surface, so do not give unnecessary details in addition at this.

In sum, but the asynchronism(-nization) that each pronunciation source of the surperficial formed groove 118 of the whirlpool type side plate 115 at tongue degree of lip-rounding shape of the present utility model 123 places produce with the amplitude 145 of noise-decreasing, allows the user feel preferable sound quality.

Frequency spectrum when the She Kou that Fig. 7 A is centrifugal fan does not form groove, it all can be observed tangible flabellum fundamental frequency noise near being positioned at the operating frequency of 900Hz and 1900Hz; Fig. 7 A then is the frequency spectrum behind snake interruption-forming one groove of centrifugal fan, by finding among Fig. 7 B, is positioned near the flabellum fundamental frequency noise of 900Hz and 1900Hz and obviously reduces.

By above-mentioned the utility model preferred embodiment as can be known, use centrifugal fan of the present utility model, its advantage is the surface of this centrifugal fan in the whirlpool type side plate at tongue degree of lip-rounding shape place, form at least one groove that roughly extends in horizontal direction, therefore when the whirlpool type side plate at the wake flow impact tongue degree of lip-rounding shape place that the fan blade rotation is produced surperficial, can reduce the noise of fan.

Claims

1. a centrifugal fan is used for a portable electronic devices, it is characterized in that, this centrifugal fan comprises at least: a housing, this housing has a whirlpool type side plate, and this whirlpool type side plate limits a cavity and an exhaust outlet, and becomes tongue degree of lip-rounding shape at this whirlpool type side plate of at least one side of this exhaust outlet; And a fan blade, this fan blade is located on this cavity; Wherein this whirlpool type side plate at this tongue degree of lip-rounding shape place forms at least one groove that extends in horizontal direction.

2. centrifugal fan as claimed in claim 1 is characterized in that, this portable electronic devices is a mobile computer.

3. centrifugal fan as claimed in claim 1 is characterized in that this groove has a rectangular cross section.

4. centrifugal fan as claimed in claim 1 is characterized in that, this groove has an arcuation section.

5. centrifugal fan as claimed in claim 1 is characterized in that, the part of this groove is the short transverse in the face of fan blade.

6. centrifugal fan as claimed in claim 5 is characterized in that, the part of this groove is the neutral position in the face of the short transverse of fan blade.

7. the housing of a centrifugal fan is used for a portable electronic devices, it is characterized in that, this housing comprises at least: a base plate; An and whirlpool type side plate, this whirlpool type side plate is arranged on this base plate and limits a cavity and an exhaust outlet, and this whirlpool type side plate at least one side of this exhaust outlet becomes tongue degree of lip-rounding shape, and wherein this whirlpool type side plate at this tongue degree of lip-rounding shape place forms at least one groove that extends in horizontal direction.

8. the housing of centrifugal fan as claimed in claim 7 is characterized in that, this portable electronic devices is a mobile computer.

9. the housing of centrifugal fan as claimed in claim 7 is characterized in that, this groove has a rectangular cross section.

10. the housing of centrifugal fan as claimed in claim 7 is characterized in that, this groove has an arcuation section.

11. the housing of centrifugal fan as claimed in claim 7 is characterized in that, fan blade is located on this cavity, and the part of this groove is the short transverse in the face of fan blade.

12. the housing of centrifugal fan as claimed in claim 11 is characterized in that, the part of this groove is the neutral position in the face of the short transverse of fan blade.