TWI894121B - Laptop computer fan device with multiple air intake holes arranged in a ring - Google Patents

Abstract

The present invention comprises a fan housing and a centrifugal fan module; the fan housing has a top plate, a bottom plate, and a side wall, forming a central space and an exhaust port therebetween; the top plate has a first air inlet; the bottom plate has an annular region, a fan fixing portion, and a second air inlet. The annular region has an inner diameter and an outer diameter; the fan fixing portion is within the inner diameter, and the second air inlet is between the inner and outer diameters; the second air inlet is provided with a plurality of air inlet holes evenly distributed in the annular region; the number of the plurality of air inlet holes is between 10 and 225; the number of circles arranged is between 1 and 5, and the total area of the plurality of air inlet holes is defined as a second total air inlet area. The centrifugal fan module rotates at 3000 rpm and has ≥30 blades. This design offers advantages such as increased air volume and pressure, flexible manufacturing of the ring-shaped air intake holes, and improved high-frequency noise reduction.

Description

Laptop computer fan device with multiple air intake holes arranged in a ring

The present invention relates to a notebook computer fan device having a plurality of annularly arranged air intake holes, and more particularly to a notebook computer fan device having a plurality of annularly arranged air intake holes that can increase air volume and pressure, facilitate manufacturing variations of the annularly arranged air intake holes, and improve high-frequency noise.

As far as fans are concerned, when there are many blades, they are more likely to produce high-frequency sounds (generally referring to noise above 2kHz), which have a negative impact on noise levels and the human ear.

The fan frequency is calculated as follows:

Fan blade frequency H=N/60*P(Hz).

Where N is the rotational speed and P is the number of fan blades.

The fan speed (N) commonly used in common cooling (or ventilation) systems mostly falls between 4000rpm and 10000rpm (speeds within this range are used).

If it is an axial flow fan, it has fewer blades (usually 5 to 11), which is less likely to cause high-frequency noise.

However, centrifugal fans generally have more blades, usually more than 30, which can easily generate high-frequency noise.

A traditional three-stage fan unit with an open base (as shown in Figures 5, 6, 7, and 8) consists of a top plate 31, a bottom plate 32, and a sidewall 33, forming a central space S1 and an exhaust port S2. The central space S1 houses a fan 40, and the bottom plate 32 has three air inlet holes 321. Because there are only three holes, the noise is often more noticeable in the 3000Hz to 5000Hz range.

Another known technology is Chinese patent CN116733785A, titled "A Noise Reduction Device for Range Hood Fans." This device is designed for range hood exhaust fans and features: "The honeycomb mesh on the sound-absorbing tube and sound-absorbing plate absorbs the noise generated by the motor, reducing its diffusion. Furthermore, the circular and curved covers form a noise-reducing cavity, further isolating and reducing the noise."

However, the range hood's exhaust fan is an axial flow fan, with a motor speed of approximately 2000 rpm and low-frequency noise, estimated at around 100 Hz. The multiple small holes (see the honeycomb mesh on the sound-absorbing tube and sound-absorbing plate in the relevant diagram) account for less than 5% of the air intake area. Furthermore, this porous sound-absorbing plate is wrapped around the exhaust fan's electric motor, acting like a soundproofing panel directly targeting the noise source.

Therefore, when used in a laptop, since the user is very close to the laptop's cooling fan (about 40 to 50 cm), if high-frequency noise (at least 10KHz or higher) is generated, the user's ears will be very uncomfortable.

In view of this, it is necessary to develop technologies that can solve the above-mentioned shortcomings.

The purpose of this invention is to provide a notebook computer fan device with multiple air intake holes arranged in a circular pattern. This device achieves the advantages of increasing air volume and pressure, facilitating manufacturing variations in the shape of the circular air intake holes, and improving high-frequency noise. Specifically, the present invention addresses the problem that conventional fan devices with three-stage openings, due to their three holes, often generate noticeable noise at frequencies between 3000Hz and 5000Hz. When used in a notebook computer, the user is very close to the cooling fan (approximately 40-50cm), and the resulting high-frequency noise (at least 10kHz or higher) often causes significant ear discomfort.

A technical solution to the above problem is to provide a notebook computer fan device having a plurality of air inlet holes arranged in a ring shape, which includes:

A fan housing comprises a top plate, a bottom plate and a side wall; the top plate and the bottom plate are parallel to each other, the side wall is connected between the top plate and the bottom plate to form a central space and an exhaust port; the top plate has a first air inlet; the bottom plate has a virtual central axis, an annular area, a fan fixing portion and a second air inlet; the annular area has an inner diameter and an outer diameter with the virtual central axis as the center point; the fan The fixing portion is located within the range of the annular inner diameter, and the second air intake portion is between the annular inner diameter and the annular outer diameter; the second air intake portion has a plurality of air intake holes of the same shape, and the plurality of air intake holes are evenly distributed in the annular area; the number of the plurality of air intake holes is between 10 and 225; and the number of circles of the plurality of air intake holes arranged in a circular shape in the annular area is between 1 and 5; and the total area of the plurality of air intake holes is defined as a second total air intake area; and

a centrifugal fan module fixed to the fan fixing portion and located in the central space; the centrifugal fan module rotates at a speed of at least 3000 rpm after startup; and the number of blades of the centrifugal fan is ≥30;

Thereby, when the centrifugal fan module is in the activated state, air can be sucked into the central space from the first air inlet portion and the second air inlet portion, and then discharged from the exhaust port.

The above-mentioned objects and advantages of the present invention can be more clearly understood from the detailed description of the following selected embodiments and the accompanying drawings.

The present invention is described in detail below with reference to the following embodiments and accompanying drawings:

Referring to Figures 1, 2, 3, and 4, the present invention is a notebook computer fan device having a plurality of air intake holes arranged in a ring shape, comprising:

A fan housing 10 comprises a top plate 11, a bottom plate 12, and a sidewall 13. The top plate 11 and bottom plate 12 are parallel to each other. The sidewall 13 connects the top plate 11 and bottom plate 12, forming a central space S1 and an exhaust port S2. The top plate 11 has a first air inlet 111; the bottom plate 12 has a virtual central axis C, an annular region R, a fan fixing portion 121, and a second air inlet 122. The annular region R is centered about the virtual central axis C and has an inner diameter D1 and an outer diameter D2. The fan fixing portion 121 is located within the range of the annular inner diameter D1, and the second air inlet portion 122 is between the annular inner diameter D1 and the annular outer diameter D2; the second air inlet portion 122 has a plurality of air inlet holes W of the same shape, and the plurality of air inlet holes W are evenly distributed in the annular region R; the number of the plurality of air inlet holes W is between 10 and 225; and the number of circles of the plurality of air inlet holes W arranged in a ring shape within the annular region R is between 1 and 5; and the total area of the plurality of air inlet holes W is defined as a second total air inlet area.

A centrifugal fan module 20 is fixed to the fan fixing portion 121 and is located in the central space S1. The centrifugal fan module 20 rotates at a speed of at least 3000 rpm after startup. The number of blades of the centrifugal fan is ≥30.

Thus, when the centrifugal fan module 20 is activated, air is drawn into the central space S1 through the first air inlet 111 and the second air inlet 122 and then exhausted through the exhaust port S2.

In practice, the first air intake portion 111 has an air intake diameter D3, and the air intake diameter D3 is greater than or equal to the annular outer diameter D2.

See Table 1 below:

Table 1 A _L /A _B Maximum flow rate Qmax (CFM)@5500rpm Maximum peak value Pmax (mmH ₂ O)@5500rpm General air inlet twenty one% 1.50 6.5 Circular arrangement of air intake holes (honeycomb air inlet) 70% 1.50 5.7 60% 1.51 6.2 50% 1.53 7.1 40% 1.55 7.9 30% 1.53 7.2 twenty one% 1.61 7.7 20% 1.63 7.5 10% 1.65 6.9 0% 1.11 6.1

Table 1 clearly shows that for a conventional air inlet with an opening area ratio ( _AL / _AB ) of 21%, its maximum flow rate is 1.50 (CFM) and its peak pressure is 6.5 ( _mmH2O ). However, the circularly arranged air inlets (also known as honeycomb air inlets) in this case achieve air volumes of 1.53 to 1.65 when the opening area ratio ranges from 10% to 50% (the optimal range), and the peak pressure exceeds 6.9, surpassing conventional air inlets.

See Table 2 below:

Table 2 Characteristics at the same noise level A _L /A _B Number of laps Number of laps Total quantity Maximum flow Qmax (CFM) @ 37dBA General air inlet twenty one% 1 lap 3 3 1.50 Circular arrangement of air intake holes (honeycomb air inlet) twenty one% 1 lap 10 10 1.53 twenty one% 2 laps 10 20 1.55 twenty one% 3 laps 30 90 1.61 twenty one% 4 laps 40 160 1.63 twenty one% 5 laps 45 225 1.57 twenty one% 6 laps 45 270 1.45

Table 2 clearly shows that, when controlling the same area ratio (21%), the following results are obtained when comparing the conventional technology with the circular arrangement of air intake holes with different numbers of circles and holes in this design:

[a] Number of circles: When the number of circles of the multiple air inlets W is between 1 and 5, the wind pressure (above 1.53) is better than that of traditional general air inlets.

[b] Total number: When the total number of the multiple air inlet holes W is (e.g., 10 to 225), the maximum flow rate is better than that of traditional general air inlets.

[c] When the number of turns exceeds 5 and becomes 6, the air volume will decrease (for example, 1.45). Therefore, the preferred embodiment of this case is limited to:

The number of the plurality of air inlet holes W is between 10 and 225; and

And the number of circles of the plurality of air inlet holes W arranged in a ring shape in the annular region R is between "1 and 5 circles", which means here.

See Table 3 below:

Table 3 A _L /A _B Number of laps Number of laps Total quantity Is there a surge? General air inlet twenty one% 1 lap 3 3 have Circular arrangement of air intake holes (honeycomb air inlet) twenty one% 1 lap 10 10 no twenty one% 2 laps 10 20 no twenty one% 3 laps 30 90 no twenty one% 4 laps 40 160 no twenty one% 5 laps 45 225 no twenty one% 6 laps 45 270 no

Table 3 clearly shows that, under the same area ratio (21%), when using the circular arrangement of air intake holes in this case, when the number of circles of the multiple air intake holes W is between 1 and 5, the noise level is better (no surge).

See Table 4 below:

Table 4 A _L /A _B shape Maximum flow (Qmax) (CFM) @ 5500rpm Maximum peak value Pmax (mmH ₂ O)@5500rpm General air inlet twenty one% Irregular 1.50 6.5 Circular arrangement of air intake holes (honeycomb air inlet) twenty one% round 1.61 7.1 twenty one% triangle 1.60 7.3 twenty one% quadrilateral 1.61 7.2 twenty one% pentagon 1.61 7.2

Table 4 clearly shows that, given the same area (21%), when using the circular arrangement of air inlets in this case, regardless of the shape of the air inlet W (circular, triangular, quadrilateral, or pentagonal), the wind pressure (7.1-7.3) and air volume (1.60-1.61) are superior to those of conventional air inlets (wind pressure 6.5 and air volume 1.50).

Regarding this solution's effective high-frequency noise reduction, Figure 9A clearly shows that it can break up flow field sound (for example, the 2000-5000Hz range), reducing the flow velocity between the fan blades. This, in turn, significantly reduces noise due to the change in the flow field, optimizing the auditory experience and noise level, and enhancing performance.

In contrast, traditional three-stage open-base fan devices (as shown in Figure 9B) are prone to generating high-velocity areas (e.g., the 2000-5000 Hz range) between the fan blades, which in turn generates disturbing high-frequency noise due to the frequency multiplication of the fan blades.

Regarding Figures 9A and 9B, the horizontal axis represents frequency in Hz, while the vertical axis represents sound pressure level (SPL), expressed in decibels relative to a reference value of 20 μPa. This can be expressed simply as dB, or decibel; more precisely, as "decibel relative to a reference value of 20 μPa" or "L/dB(A)."

The advantages and effects of the present invention can be summarized as follows:

[1] It can increase the air volume and air pressure. When the number of the plurality of air inlets is between 10 and 225, the maximum flow rate is better than that of a conventional general air inlet. And when the number of circles of the plurality of air inlets arranged in a ring shape in the annular area is between 1 and 5, the air pressure is better than that of a conventional general air inlet. Therefore, it can increase the air volume and air pressure.

[2] The shape of the circularly arranged air inlets is not restricted and is easy to manufacture. Under the same area (21%), when using the circularly arranged air inlets of this case, regardless of the shape of the air inlet outline (such as circular, triangular, square or pentagonal), the wind pressure (7.1-7.3) and air volume (1.60-1.61) are better than those of the general air inlet (wind pressure 6.5 and air volume 1.50). Therefore, the shape of the circularly arranged air inlets is not restricted and is easy to manufacture.

[3] It can improve high-frequency noise. Since this solution is used in laptop computers, the fan speed is relatively high, at least between 3000rpm and 10000rpm (it can reach 10000rpm when Turbo is activated). This solution is limited to the range of 3000rpm to effectively reduce noise. Therefore, it can improve high-frequency noise.

The above is merely a detailed description of the present invention through preferred embodiments. Any simple modifications and changes made to the embodiments do not deviate from the spirit and scope of the present invention.

10: Fan housing 11, 31: Top plate 111: First air intake 12, 32: Bottom plate 121: Fan mounting 122: Second air intake 13, 33: Sidewalls 20: Centrifugal fan module 40: Fan S1: Central space S2: Exhaust port C: Virtual center axis R: Annular area D1: Annular inner diameter D2: Annular outer diameter D3: Inlet diameter 321, W: Inlet hole

FIG1 is a schematic diagram showing the appearance of the present invention when rotated 180 degrees.

Figure 2 is an exploded diagram of Figure 1.

Figure 3 is a top view of Figure 1.

Figure 4 is a cross-sectional view taken at position IV-IV in Figure 3.

Figure 5 is a diagram showing a conventional fan device rotated 180 degrees.

FIG6 is an exploded diagram of FIG5.

Figure 7 is a top view of Figure 5.

Figure 8 is a cross-sectional view of the VIII-VIII position in Figure 7.

FIG. 9A is a schematic diagram of the waveform of the present invention that can disperse flow field sound and reduce noise.

FIG9B is a diagram showing a high velocity region and a high-frequency sound waveform generated between blades of a conventional fan device.

10: Fan housing

12: Bottom plate

122: Second air intake

13: Side wall part

S2: Exhaust port

C: Virtual central axis

R: Ring area

D1: Ring inner diameter

D2: Ring outer diameter

W: Air Intake

Claims (2)

A notebook computer fan device with a plurality of air inlet holes arranged in a ring comprises: a fan housing having a top plate portion, a bottom plate portion and a side wall portion; the top plate portion and the bottom plate portion are parallel to each other, the side wall portion is connected between the top plate portion and the bottom plate portion to form a central space and an air outlet; the top plate portion has a first air inlet portion; the bottom plate portion The plate portion has a virtual central axis, an annular area, a fan fixing portion, and a second air inlet portion; the annular area is centered on the virtual central axis and has an annular inner diameter and an annular outer diameter; the fan fixing portion is located within the annular inner diameter, and the second air inlet portion is between the annular inner diameter and the annular outer diameter; the second air inlet portion has a plurality of The plurality of air inlet holes are uniformly distributed in the annular region; the number of the plurality of air inlet holes is between 10 and 225; the number of the plurality of air inlet holes arranged in an annular pattern in the annular region is between 1 and 5; and the total area of the plurality of air inlet holes is defined as a second total air inlet area; and a centrifugal fan module is fixed The centrifugal fan module is fixed on the fan fixing portion and is located in the central space. The rotation speed of the centrifugal fan module after startup is at least 3000 rpm. In addition, the number of blades of the centrifugal fan is ≥30. Thus, when the centrifugal fan module is started, air can be sucked into the central space through the first air inlet portion and the second air inlet portion and then discharged through the exhaust port. The notebook computer fan device having a plurality of air intake holes arranged in a ring as described in claim 1, wherein the first air intake portion has an air intake diameter, and the air intake diameter is ≧ the outer diameter of the ring.