JP4191431B2 - cooling fan - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cooling fan suitable for use as an air conditioning facility for a vehicle.
[0002]
[Prior art]
In general, in cooling fans used in vehicle air conditioning equipment, in order to improve the performance of cooling fans, the propellers provided in axial fans are increased in diameter and standardized, and at the same time, the size of cooling fans has been reduced. Yes.
[0003]
FIG. 5 is a diagram illustrating a conventional cooling fan.
The cooling fan 60 includes a shroud 64 having an opening 66 for introducing air, and an axial fan 62 disposed so as to face the opening 66.
The peripheral edge 68 of the opening 66 is provided with a bell mouth shape portion 65 whose diameter gradually decreases in the air introduction direction.
The bell mouth shape portion 65 has a cross-sectional shape that is uniform in the circumferential direction.
Further, the side wall portion 67 of the shroud 64 is provided so as to protrude in the direction opposite to the air introduction direction.
[0004]
By the way, in recent years, there has been a demand for reducing the space for storing the cooling fan as small as possible, and the cooling fan has been downsized.
The cooling fans shown in FIG. 6 and FIG. 7 are considered in consideration of downsizing of the cooling fan.
[0005]
6 and FIG. 7, the same components as those in the cooling fan shown in FIG.
The cooling fan 70 is configured by setting a cut portion on the area of the bell mouth shape portion 75 in the vertical direction of the shroud 74 to reduce the vertical dimension.
The side wall 77 of the shroud 74 includes an upper portion 81 and a lower portion 82 provided by cutting a part of the bell mouth shape portion 75, a left portion 83, a right portion 84, and a corner portion that do not contact the bell mouth shape portion 75. 85, 86, 87, 88.
Further, the side wall 77 is provided so as to protrude in the direction opposite to the air introduction direction.
[0006]
[Problems to be solved by the invention]
By the way, in the conventional cooling fan shown in FIG. 6 and FIG. 7, the flow of the air flowing through the cooling fan 70 becomes non-uniform due to the non-uniform shape of the bellmouth shaped portion 75, and the axial fan is prepared. There is a problem that noise of a single frequency determined by the fan rotation speed and the number of blades, which is called NZ sound, is generated by inducing an interference sound of the propeller 63 to be generated.
[0007]
The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a cooling fan in which the flow of air is uniform and noise can be reduced.
[0008]
[Means for Solving the Problems]
The present invention employs the following means in order to solve the above problems.
The invention according to claim 1 includes a shroud having an opening for introducing air, and an axial fan disposed so as to face the opening, and a peripheral portion of the opening of the shroud is configured to introduce air. A bell mouth shape portion whose diameter gradually decreases toward the direction is provided, and a side wall portion protruding in a direction opposite to the air introduction direction is provided on a part of the peripheral edge portion, In the cooling fan provided by cutting a part of the bell mouth shape part, between the side wall part cutting the part of the bell mouth shape part at the peripheral part of the opening of the shroud, the side wall part and A ridge protruding in the same direction is formed, and the ridge has a height, width or radius of curvature so that the flow of air introduced between the side walls is equalized in the circumferential direction. Center in the circumferential direction between the side wall portions Characterized in that it is gradually increased, wide or larger toward.
[0009]
According to the present invention, the ridge is formed between the side walls that cut a part of the bell mouth shape portion at the peripheral edge of the opening of the shroud, and the ridge is a flow of air introduced between the side walls. So that the height, width or radius of curvature is gradually increased, widened or enlarged toward the central portion in the circumferential direction between the side wall portions , so that the air to be introduced is equalized in the circumferential direction. The flow is adjusted so that the flow is uniform in the circumferential direction.
[0010]
According to a second aspect of the present invention, the cooling fan according to claim 1, characterized in that the ridge is clamped by the peripheral edge.
[0011]
According to this invention, the flow of the air to be introduced is adjusted and the flow is uniform by attaching the protrusion to the peripheral edge.
[0012]
According to a third aspect of the present invention, in the cooling fan according to the first or second aspect , the cross-sectional shape of the protruding portion is any one of a hollow, a solid rectangle, a triangle, and a semicircle. .
[0013]
According to this invention, since the cross-sectional shape of the protrusion is any one of a hollow, solid rectangle, triangle, and semicircle, the flow of air to be introduced is adjusted and a uniform flow is obtained.
[0014]
According to claim 4 invention, the cooling fan according to claim 1, characterized in that the protrusions are integrally molded to the shroud.
[0015]
According to this invention, the flow of the introduced air is adjusted and formed into a uniform flow by being integrally formed with the shroud of the ridge portion.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a first embodiment of the present invention, and is a diagram showing a cooling fan to which the present invention is applied.
In FIG. 1, reference numeral 10 denotes a cooling fan to which the present invention is applied.
The cooling fan 10 includes a shroud 14 having an opening 16 for introducing air and an axial fan 12 disposed so as to face the opening 16. The peripheral edge 18 of the opening 16 is provided with a bell mouth-shaped portion 15 whose diameter gradually decreases in the air introduction direction.
The side wall portion 17 of the shroud 14 includes an upper portion 21 and a lower portion 22 in which a part of the bell mouth shape portion 15 is cut, a left portion 23 and a right portion 24 that do not contact the bell mouth shape portion 15, and corner portions 25, 26, 27 and 28.
The side wall portion 17 is provided so as to protrude in the direction opposite to the air introduction direction.
The peripheral edge 18 is provided with a protrusion 19 that protrudes in the same direction as the side wall 17 and is provided in an arc shape with a certain thickness between the upper part 21 and the lower part 22.
The height of the ridge 19 is constant in the circumferential direction of the opening 16 and is set slightly lower than the height of the side wall 17.
[0017]
In said structure, the cross-sectional shape of the protrusion part 19 is a solid rectangle.
The material used for the protruding portion 19 is an insulator such as rubber.
[0018]
Next, the operation of the cooling fan configured as described above will be described.
When the cooling fan 10 is activated and the axial fan 12 is rotated, air is introduced into the opening 16 from the front of the cooling fan 10. The air is introduced from the outside of the side wall part 17, but the flow of air is reduced by the lack of a part of the bell mouth shape part 15 in the upper part 21 and the lower part 22 of the side wall part 17.
[0019]
Here, in the left part 23 and the right part 24 of the side wall part 17, when the ridge part 19 is not attached to the peripheral part 18, the bell mouth shape part 15 is not lost, so that the air flow is growing.
Therefore, a difference occurs in the form of the air flow introduced into the opening 16, the air flow interferes and becomes non-uniform, inducing an interference sound of the propeller 13 provided in the axial fan 12, and the NZ sound. A single frequency noise determined by the number of fan rotations and the number of blades is generated.
[0020]
However, in the cooling fan 10, since the ridge 19 is attached to the peripheral edge 18, the flow of air introduced from the outside is the ridge in the left part 23 and the right part 24 of the side wall part 17. 19 is suppressed.
Therefore, since the flow of the air introduced into the cooling fan 10 is equalized, the interference sound of the propeller 13 provided in the axial fan 12 is suppressed.
[0021]
According to said structure, since the equalization of the flow of the air introduce | transduced into the cooling fan 10 is achieved, since the interference sound of the propeller 13 is suppressed, generation | occurrence | production of noise can be reduced.
[0022]
In the first embodiment, the material used for the ridge portion 19 may be an insulator other than rubber, a steel material, or the like.
[0023]
FIG. 2 is a diagram showing a second embodiment of the present invention, and is a diagram showing a cooling fan to which the present invention is applied.
In FIG. 2, the basic configuration is the same as that of the first embodiment shown in FIG.
In FIG. 2, the same components as those in FIG. 1 in the first embodiment are denoted by the same reference numerals, and only differences from the first embodiment will be described below.
[0024]
In the cooling fan 20, the peripheral edge portion 18 is provided with a protruding portion 29 that protrudes in the same direction as the side wall portion 17 and is provided in an arc shape with a certain thickness between the upper portion 21 and the lower portion 22. Yes.
The protruding portion 29 is formed integrally with the shroud 14.
The height of the ridge 29 is appropriately changed toward the circumferential direction of the opening 16. That is, the height of the ridge 29 in the upper portion 21 of the side wall portion 17 is provided low, the height of the ridge 29 is gradually increased from the upper portion 21 to the central portion 30, and the lower portion 22 from the central portion 30. The height of the protruding portion 29 is provided so as to gradually decrease.
[0025]
Next, the operation of the cooling fan configured as described above will be described.
When the cooling fan 20 is activated and the axial fan 12 is rotated, air is introduced into the opening 16 from the front of the cooling fan 20. The air is introduced from the outside of the side wall part 17, but the flow of air is reduced by the lack of a part of the bell mouth shape part 15 in the upper part 21 and the lower part 22 of the side wall part 17.
[0026]
On the other hand, in the left portion 23 and the right portion 24 of the side wall portion 17, when the protrusion portion 29 is not provided on the peripheral edge portion 18, the bell mouth shape portion 15 is not lost, so that the air flow increases. As described above, the air flow interferes and becomes non-uniform and noise is generated. However, in this cooling fan 20, since the protrusion portion 29 is provided on the peripheral edge portion 18, the left side of the side wall portion 17. In the portion 23 and the right portion 24, the flow of air introduced from the outside is suppressed by the protrusion 29.
[0027]
Therefore, also in the second embodiment, since the flow of air introduced into the cooling fan 20 is equalized, the interference sound of the propeller 13 is suppressed. Therefore, the second embodiment is the same as the first embodiment. Similar effects can be obtained.
[0028]
In each of the above-described embodiments, the height or width of the protrusions 19 and 29 may be appropriately changed toward the circumferential direction of the opening 16.
Moreover, in said each embodiment, the cross-sectional shape of the protrusion parts 19 and 29 is good also as arbitrary shapes.
For example, in the first embodiment, as shown in FIG. 3, the cross-sectional shape of the ridge portion 19 is a solid triangle, a semicircle, or a hollow rectangle, a triangle, or a semicircle. Good.
Further, in the second embodiment, as shown in FIG. 4, the cross-sectional shape of the peripheral portion 48 of the shroud 44 is such that the protrusion 49 and the bell mouth shape portion 45 are integrally formed, and the bell mouth shape portion 45 is A shape in which the radius of curvature of the bell mouth shape portion 45 is appropriately changed toward the circumferential direction of the opening 46 may be used.
[0029]
In this way, by adopting a configuration in which the ridges 19, 29, and 49 are changed, the flow of air introduced into the cooling fan 10 can be equalized, and noise generation can be reduced.
[0030]
【The invention's effect】
The cooling fan of the present invention described above has the following effects.
According to the invention which concerns on Claim 1, a protrusion is formed between the side wall parts which cut | disconnect a part of bellmouth shape part in the peripheral part of the opening part of a shroud, and a protrusion part is introduce | transduced between side wall parts. The height, width, or radius of curvature is gradually higher, wider, or larger toward the center in the circumferential direction between the side walls so that the air flow is equalized in the circumferential direction. This makes it possible to equalize the non-uniform air flow, thereby suppressing the induction of interference sound with the propeller provided in the axial fan and reducing the generation of noise.
[0031]
According to the second aspect of the present invention, since the protrusion is attached to the peripheral portion, it is possible to equalize the non-uniform air flow, and therefore, the interference sound with the propeller provided in the axial fan. Induction is suppressed, and noise generation can be reduced.
[0032]
According to the invention of claim 3 , since the cross-sectional shape of the ridge is a hollow or solid rectangle, triangle, or semicircular shape, it is possible to equalize uneven air flow. Therefore, the induction of interference sound with the propeller provided in the axial fan is suppressed, and the generation of noise can be reduced.
[0033]
According to the fourth aspect of the invention, since the protrusion is formed integrally with the shroud, it is possible to equalize the non-uniform air flow, and therefore, the interference sound with the propeller provided in the axial fan is reduced. Induction is suppressed and the generation of noise can be reduced.
[Brief description of the drawings]
1A and 1B are views showing a cooling fan according to a first embodiment of the present invention, in which FIG. 1A is a plan view thereof and FIG. 1B is a partial perspective view thereof.
FIGS. 2A and 2B are views showing a cooling fan according to a second embodiment of the present invention, in which FIG. 2A is a plan view and FIG. 2B is a partial perspective view thereof.
FIG. 3 is a cross-sectional view of a protrusion of the cooling fan according to the first embodiment of the present invention.
FIG. 4 is a partial perspective view of a protrusion of a cooling fan according to a second embodiment of the present invention.
FIG. 5 is a plan view showing a conventional cooling fan.
6A and 6B are views showing a cooling fan in which a part of a conventional bell mouth shape portion is missing, in which FIG. 6A is a plan view thereof, and FIG. 6B is a partial perspective view thereof.
FIGS. 7A and 7B are views showing a cooling fan in which a part of a conventional bell mouth shape portion is missing, and FIGS. 7A and 7B are cross-sectional views thereof. FIGS.
[Explanation of symbols]
10, 20, 60, 70 Cooling fan 11, 61 Axial fan 14, 64 Shroud 19, 29, 49 Projection

Claims (4)

A shroud having an air introduction opening, and an axial fan disposed so as to face the opening, and the peripheral edge of the opening of the shroud has a gradually decreasing diameter in the air introduction direction. And a side wall portion projecting in a direction opposite to the direction of air introduction is provided on a part of the peripheral edge portion, and the side wall portion is a part of the bell mouth shape portion. In the cooling fan provided by cutting,
A ridge projecting in the same direction as the side wall is formed between the side walls that cut a part of the bell mouth shape portion at the peripheral edge of the opening of the shroud, and the ridge is The height, width, or radius of curvature of the air flow introduced between the side wall portions is gradually higher, wider, or larger toward the center portion in the circumferential direction between the side wall portions so as to be equalized in the circumferential direction. Cooling fan characterized by being made . The cooling fan according to claim 1 , wherein
The cooling fan, wherein the protruding portion is attached to the peripheral portion. The cooling fan according to claim 1 or 2,
The cooling fan according to claim 1, wherein a cross-sectional shape of the protrusion is a hollow or solid rectangle, triangle, or semicircle. The cooling fan according to claim 1, wherein
The cooling fan, wherein the protrusion is integrally formed with the shroud.

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