Patent Application
20240084816
The present invention relates to a fan shroud assembly, and more particularly, to a fan shroud assembly in which a fan, which forcibly blows air, is supported on an air-cooled heat exchanger and coupled to the heat exchanger, and a structure capable of reducing noise during a process of blowing air is provided.
In general, various air conditioning systems, cooling systems, and the like are installed in vehicles. The air conditioning system approximately includes cooling and heating modules for adjusting air a temperature, a humidity, and the like in an interior space in which a vehicle occupant is present. The cooling system includes modules for cooling an engine, a motor, and the like to prevent the engine, the motor, and the like from being overheated. These various modules are configured to implement desired cooling, heating, and refrigerating operations by transferring heat while circulating heat exchange media such as a refrigerant and a coolant.
The air conditioning system or the cooling system includes various heat exchangers. Among the heat exchangers, there is an air-cooled heat exchanger that cools a heat exchange medium therein by using outside air. As well known, heat exchange efficiency is improved as a velocity of air flowing to a core of the air-cooled heat exchanger. Therefore, generally, a fan shroud is coupled to a front surface of the air-cooled heat exchanger to forcibly blow air toward the core of the heat exchanger without allowing the heat exchange to be performed only by vehicle-induced wind. The fan shroud refers to a kind of device assembling component that stably supports a fan, which includes a hub and a plurality of blades, and a motor, which is configured to rotate the fan, and enables the fan and the motor to be coupled to another device.
Meanwhile, significant noise inevitably occurs during a process in which the fan forcibly blows air. More specifically, generally, noise with a pulsation waveform having a frequency, which is the product of the number of blades and the rotational speed, occurs when a fluid, which is transported by fluid transport blades in a fluid machine, passes through a cut-off portion of the fluid machine. The noise is referred to as a blade pass frequency (BPF) noise. The blades of the fan 200 correspond to the fluid transport blades, and the ventilation port 150 corresponds to a cut-off portion. The BPF noise significantly occurs even in the fan shroud assembly when the fan 200 operates.
Various studies have been conducted to improve a shape or structure of the fan shroud to reduce the BPF noise. As an example, Korean Patent Laid-Open No. 2013-0111744 (“Fan Shroud for Reducing Noise”, Oct. 11, 2013) discloses a fan shroud which is illustrated in
In another example disclosed in “Reduction of the BPF Noise Radiated from an Engine Cooling Fan” (Yoshida K. et al., SAE 2014 World Congress & Exhibition, Apr. 1, 2014), an attempt has been made to reduce the BPF noise by changing a shape of the fan shroud.
Therefore, the present invention has been made in an effort to solve the above-mentioned problem in the related art, and an object of the present invention is to provide a fan shroud assembly including a fan shroud having a peripheral part configured to surround an outer periphery of a fan, and a planar part coupled to face a heat exchanger, in which a noise-reducing hole is formed at an appropriate position and defined by connecting a first hole, which extends in a circumferential direction of the peripheral part, and a second hole, which extends toward the planar part and is formed through the planar part, thereby effectively reducing BPF noise while minimizing deterioration in rigidity and durability of the fan shroud.
To achieve the object, the present invention provides a fan shroud assembly including: a fan 200 including a hub coupled to a rotary shaft of a motor, and a plurality of blades provided on an outer peripheral surface of the hub; and a fan shroud 100 including a peripheral part 110 configured to surround an outer periphery of the fan 200, a planar part 120 coupled to face a heat exchanger, a ventilation port 150 provided in the form of an empty space formed in a central portion of the peripheral part 110 and configured to allow an airflow, which is generated by the fan 200, to pass through the ventilation port 150 to blow air, a hub part 151 formed at a center of the ventilation port 150 and configured to accommodate and support the motor provided on a shaft of the fan 200, and a plurality of fixing members 152 connected to an inner peripheral edge of the peripheral part 110 and an outer peripheral edge of the hub part 151 and disposed radially around the hub part 151, in which a lateral surface is formed as the peripheral part 110 protrudes from a surface of the planar part 120, and in which at least one noise-reducing hole 10 is formed through the lateral surface of the peripheral part 110 and communicates with the ventilation port 150 to control a part of the airflow passing through the ventilation port 150.
In this case, the noise-reducing hole 10 may be formed by a first hole 11 formed in the lateral surface of the peripheral part 110 and extending in a circumferential direction of the peripheral part 110.
In addition, the noise-reducing hole 10 may be formed by connecting a second hole 12 formed in the lateral surface of the peripheral part 110, extending toward the planar part 120 so as to be inclined with respect to the first hole 11, and formed through the planar part 120.
In addition, the first hole 11 and the second hole 12 may be perpendicularly connected in the noise-reducing hole 10.
When a portion where a circular shape defined by the peripheral part 110 and a rectangular shape defined by the planar part 120 overlap each other or are disposed adjacent to each other is referred to as a narrow portion, the fan shroud 100 may have upper and lower narrow portions where the circular shape of the peripheral part 110 and the rectangular shape of the planar part 120 overlap each other, and first and second intermediate narrow portions that are positions at which the peripheral part 110 has a maximum horizontal length, i.e., vertical centerline positions of the peripheral part 110, and the noise-reducing hole 10 may be formed on at least one position selected from the upper narrow portion, the lower narrow portion, and the first and second intermediate narrow portions.
In addition, the noise-reducing hole 10 may be formed only in any one selected from the first and second intermediate narrow portions.
When widths of the first and second intermediate narrow portions are widths between the circular shape of the peripheral part 110 and the rectangular shape of the planar part 120 at the positions of the first and second intermediate narrow portions, the noise-reducing hole 10 may be formed only at a side at which the width is small when the widths of the first and second intermediate narrow portions are different from each other.
In addition, the noise-reducing hole 10 may be formed such that the length of the first hole 11 is longer than the length of the second hole 12 and shorter than 5% of a circumference length of the peripheral part 110.
More specifically, the noise-reducing hole 10 may be formed such that the length of the first hole 11 is within a range of 30 to 50 mm.
In addition, the noise-reducing hole 10 may be formed such that at least one second hole 12 is formed for the single first hole 11.
In addition, the noise-reducing hole 10 may be formed such that the single second hole 12 is formed for the single first hole 11, and the second hole 12 is formed at a center position based on an extension direction of the first hole 11.
In addition, the noise-reducing hole 10 may be formed such that widths of the first and second holes 11 and 12 are within a range of 10 to 30 mm.
In addition, the peripheral part 110 may include anti-vortex serrated portions 115 formed in a serrated shape and arranged along a predetermined region of an outer peripheral surface of the peripheral part 110, and the noise-reducing hole 10 may be formed in a region excluding a region in which the anti-vortex serrated portion 115 is formed.
According to the present invention, the hole having the optimized shape is formed at the appropriate position on the fan shroud, such that a great effect of effectively reducing the BPF noise may be obtained. More specifically, in the present invention, the noise-reducing hole is formed by connecting the first hole, which extends in the circumferential direction of the peripheral part configured to surround the fan of the fan shroud, and the second hole, which is formed through the planar part and extends toward the planar part facing the heat exchanger, and the noise-reducing hole is formed at the centerline position of the fan shroud at which the flows of air are collected, thereby effectively reducing the BPF noise by reducing interference between the peripheral part and the air.
In addition, according to the present invention, it is not necessary to form an unnecessarily large number of noise-reducing holes. In general, the rigidity and durability inevitably deteriorate when the hole is formed in any structure. Therefore, it is possible to minimize the deterioration in rigidity and durability by minimizing the number of holes.
Furthermore, in the related art, in case that the additional airflow space is formed in the narrow portion to reduce the BPF noise, the asymmetric shape of the fan shroud causes problems in which additional vibration occurs, the deterioration in rigidity and durability is caused by the vibration, and new vibration and noise occur. In contrast, the shape of the fan shroud according to the present invention does not have asymmetry, thereby basically eliminating the above-mentioned problems. Further, in the related art, the additional airflow space protrudes, which causes a problem of unnecessary interference with the peripheral object at the time of packaging the cooling module. In contrast, the present invention does not cause the problem.
Hereinafter, a fan shroud assembly according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.
[1] Overall Configuration of Fan Shroud Having Noise-Reducing Hole According to Present Invention
In this case, at least one noise-reducing hole 10 is formed through the lateral surface of the peripheral part 110 of the fan shroud 100 of the present invention and communicates with the ventilation port 150, thereby controlling a part of an airflow passing through the ventilation port 150 and reducing BPF noise caused by the airflow. In this case, in case that the anti-vortex serrated portions 115 are provided on the peripheral part 110, the noise-reducing hole 10 may be formed in a region excluding a region in which the anti-vortex serrated portions 115 are formed. When the airflow is intentionally and additionally formed by the noise-reducing hole 10, a shape of a flow, which causes BPF noise, may be changed from an original airflow, which makes it possible to reduce the BPF noise.
The noise-reducing hole 10 of the present invention may be basically formed as a first hole 11 formed in the lateral surface of the peripheral part 110 and extending in a circumferential direction of the peripheral part 110. In addition, as illustrated in an enlarged view in
As described above, the noise-reducing hole 10 of the present invention, which has a special shape, may be formed at an appropriate position on the fan shroud 100, thereby more effectively reducing the BPF noise. Hereinafter, various embodiments for deriving an optimal position, a basic shape, an optimal shape, and the like of the noise-reducing hole 10 will be described in more detail.
[2] Embodiment for Deriving Optimal Position of Noise-Reducing Hole in Fan Shroud of Present Invention
The ventilation port 150 is formed in the central portion of the peripheral part 110, and the planar part 120 is coupled to face the heat exchanger. A relatively large amount of air is accumulated and collected on a portion where the circular shape defined by the peripheral part 110 and the rectangular shape defined by the planar part 120 overlap each other or are disposed adjacent to each other, such that a large amount of air flows in the relatively narrow region, which causes the BPF noise. In the fan shroud 100 in the embodiment illustrated in
Meanwhile, in consideration of structural rigidity of a structure, the noise-reducing hole 10 may be considered as a flaw formed in the structure. Therefore, the noise-reducing hole 10 may be minimally formed in consideration of the rigidity and durability of the fan shroud 100. The problems or relative advantages and disadvantages made by the narrow portions will be described below.
The upper narrow portion is a portion indicated by Sample_A2 in
The lower narrow portion is a portion indicated by Sample_A3 in
The first intermediate narrow portion is a portion indicated by Sample_A1 in
In consideration of these various factors, the noise-reducing hole 10 may be basically formed only at any one selected from the positions of the first and second intermediate narrow portions. In addition, on the assumption that the widths of the first and second intermediate narrow portions are widths between the circular shape of the peripheral part 110 and the rectangular shape of the planar part 120 at the positions of the first and second intermediate narrow portions, the noise-reducing hole 10 may be formed only at a side at which the width is small in case that the widths of the first and second intermediate narrow portions are different from each other.
[3] Embodiment for Deriving Basic Shape of Noise-Reducing Hole in Fan Shroud of Present Invention
In the experiment illustrated in the upper view in
As clearly shown in the results in Table 1, it can be ascertained that the BPF noise is reduced by about 2.5 dB in Sample_B2 having the noise-reducing hole 10 formed only by the first hole 11 in comparison with Sample_B1 that corresponds to the fan shroud in the related art in which the noise-reducing hole 10 is not formed. In addition, it can be ascertained that in comparison with Sample_B2, the BPF noise is reduced by about 3 dB and more excellent performance is exhibited in Sample_B3 in which the noise-reducing hole 10 is formed by a combination of the first hole 11 and the second hole 12. That is, it has been experimentally proven that the effect of reducing the BPF noise is improved as the accumulated air is more smoothly discharged when the second hole 12 is further formed.
The configuration of the present invention in which the noise-reducing hole 10 is formed by the combination of the first hole 11 and the second hole 12 is made by applying the above-mentioned experimental result.
[4] Embodiment for Deriving Optimal Shape of Noise-Reducing Hole in Fan Shroud of Present Invention
As clearly shown in the results in Table 2, the effect of reducing the BPF noise is improved as the length of the first hole 11 increases. Specifically, it can be ascertained that the BPF noise is reduced by about 3 dB in Sample_C1 in which the length of the first hole 11 is 45 mm, the BPF noise is reduced by about 2.5 dB in Sample_C2 in which the length of the first hole 11 is 35 mm, and the BPF noise is reduced by about 2 dB in Sample_C3 in which the length of the first hole 11 is 25 mm.
As such, it can be considered that the longer length of the first hole 11 is effective only based on the fact that the effect of reducing the BPF noise is improved as the length of the first hole 11 increases. However, as described above, because the noise-reducing hole 10 itself may act as a structurally damaged portion in the fan shroud 100, the excessively large noise-reducing hole 10 may cause the deterioration in undesired rigidity and durability.
In consideration of these various factors, the noise-reducing hole 10 may be formed such that the length of the first hole 11 is longer than the length of the second hole 12 and shorter than 5% of a circumference length of the peripheral part 110. When the dimensions of the general fan shroud 100 are expressed in specific numerical values, the noise-reducing hole 10 may be formed such that the length of the first hole 11 is within a range of 30 to 50 mm.
It can be expected that the effect of discharging air is improved as the number of second holes 12 increases. However, actually, the effect of discharging air is excellent when the second hole 12 is formed at the center position of the first hole 11, and the effect tends to significantly deteriorate as the position of the second hole 12 approaches the two opposite ends. Further, from the point of view of manufacturability, there is a problem in that the more complex the shape of the noise reduction hole 10, the more difficult it is to manufacture the noise-reducing hole 10. In consideration of these factors, as in Sample D1 in
Meanwhile, the widths of the first and second holes 11 and 12 may be considered. For ease of design, it may be easiest to form the first and second holes 11 and 12 having the same width. However, in consideration of the effect of discharging air, the width of the second hole 12 may be larger than the width of the first hole 11. However, the widths of the first and second holes 11 and 12 may be within a range of 10 to 30 mm in consideration of the dimensions of the general fan shroud 100 so that the rigidity and durability of the fan shroud 100 are not unnecessarily excessively reduced because of the presence of the noise-reducing hole 10, as described above.
The present invention is not limited to the above embodiments, and the scope of application is diverse. Of course, various modifications and implementations made by any person skilled in the art to which the present invention pertains without departing from the subject matter of the present invention claimed in the claims.
According to the present invention, the hole having the optimized shape is formed at the appropriate position on the fan shroud, such that a great effect of effectively reducing the BPF noise may be obtained. The compatibility of the hole is high because the hole is applied without changing the entire structure of the fan shroud in the related art, which is advantageous in manufacturing and producing the fan shroud.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0016309 | Feb 2021 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/001516 | 1/27/2022 | WO |
