JP2017137839A - Centrifugal fan device, projection type display device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a centrifugal fan device capable of enhancing cooling effect of an enclosure that has a complex internal structure and decreasing size of a portion protruding to the outside of the enclosure.SOLUTION: A centrifugal fan device includes an impeller 3 which is equipped with a disc 3a in which a plurality of blades 5 are provided in circumferential direction and when the disc 3a is rotated, air intake is performed in rotational axis direction and air-discharging is performed in centrifugal direction, a lower casing 9 to which the impeller 3 is fixed, and an upper casing 8 for housing the impeller 3 fixed to the lower casing 9. The upper casing 8 includes an air intake port 12 at a portion intersecting with a rotational axis 6 direction. An annular exhaust opening is formed with an outer peripheral end part of the lower casing 9 and an outer peripheral end part of the upper casing 8, for exhausting the air being exhausted in centrifugal direction through the exhaust opening.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a centrifugal blower capable of exhausting in a centrifugal direction, a projection display device including the centrifugal blower, and an electronic apparatus.

In recent projection type display devices, miniaturization and high output have been achieved, and the internal structure of the housing has become complicated accordingly. On the other hand, the air in the housing is exhausted using a blower to suppress the temperature rise of the internal structure. However, this exhaust cooling does not correspond to the complexity of the internal structure and is sufficient. The cooling effect is not obtained. For this reason, there is a demand for the realization of a blower capable of obtaining a sufficient exhaust cooling effect even if the internal structure is complicated.
A centrifugal fan such as a sirocco fan or a turbo fan, or an axial fan can be used as the exhaust fan.

An axial fan has a feature that the air flow is larger than that of a centrifugal fan, but the static pressure is low. On the other hand, the centrifugal fan has a feature that the air pressure is small although the static pressure is higher than that of the axial fan. Here, the static pressure refers to the pressure that the fluid actually exerts on the outside world. For example, when exhausting the air in the casing, the resistance (ventilation resistance) of the inner surface of the casing and the internal structure is determined. On the other hand, it refers to the force required to send out air. The air volume means the volume of air discharged per unit time.
Since the axial fan has a low static pressure, it is easily affected by the resistance of a structure in the housing. For this reason, when exhausting the air in the housing | casing which has a complicated internal structure using an axial fan, since it receives to the influence of resistance of a structure etc., it is difficult to exhaust air efficiently.
On the other hand, since the centrifugal fan has a high static pressure, it is not easily affected by the resistance of a structure or the like in the housing. For this reason, if the air in the housing | casing which has a complicated internal structure is exhausted using a centrifugal fan, air can be exhausted efficiently. However, since the centrifugal fan generally has a low air volume, it is difficult to obtain a sufficient cooling effect.

Therefore, a centrifugal fan capable of increasing the air volume has been proposed. For example, Patent Literature 1 and Patent Literature 2 describe a centrifugal fan in which a casing is configured so that air blows out over the entire circumference (360 °). The centrifugal fan includes an upper casing having a suction port, a lower casing provided so as to face the upper casing, a plurality of support columns that support the upper and lower casings in parallel, and an upper casing and a lower casing. And an impeller housed in the housing.
The impeller has a plurality of blades arranged in the centrifugal direction. When the impeller rotates, air is taken in from the suction port of the upper casing and exhausted in the centrifugal direction. A gap between the outer peripheral end of the upper casing and the outer peripheral end of the lower casing is a blowout port for air exhausted in the centrifugal direction.
Since the centrifugal fan has less exhaust-side resistance than a centrifugal fan in which a casing is configured so that air blows out in one direction, the air volume can be increased. Therefore, if the air in the housing | casing which has a complicated internal structure is exhausted using said centrifugal fan, a high cooling effect can be acquired.

JP 2012-202368 A JP 2012-207602 A

However, the centrifugal fans described in Patent Document 1 and Patent Document 2 have the following problems.
When the centrifugal fan is attached to the housing, the upper casing is fixed to the surface of the housing with the suction port of the upper casing and the exhaust port provided in the housing being aligned. In this case, the centrifugal fan is attached in a state of protruding outward from the surface of the housing. The protruding centrifugal fan portion (protruding portion) not only impairs the appearance, but also may be damaged when the protruding portion comes into contact with other structures during carrying.
SUMMARY OF THE INVENTION An object of the present invention is to provide a centrifugal blower that can enhance the exhaust cooling effect of a casing having a complicated internal structure and that can reduce the portion protruding to the outside of the casing, and the centrifugal blower. Another object of the present invention is to provide a projection display device and an electronic apparatus.

In order to achieve the above object, according to one aspect of the present invention,
An impeller in which a plurality of blades are provided with a circular plate provided in the circumferential direction, and the circular plate rotates so that intake is performed in the rotation axis direction and exhaust is performed in the centrifugal direction;
A first casing to which the impeller is fixed;
A second casing that houses the impeller fixed to the first casing;
The second casing includes a first opening for performing the intake at a portion intersecting the rotation axis direction,
A centrifugal blower is provided in which an outer peripheral end of the first casing and an outer peripheral end of the second casing form an annular second opening for performing the exhaust.

According to another aspect of the invention,
A housing that houses a light source, an image forming unit that spatially modulates light from the light source to form an image, and a projection optical system that projects the image;
The centrifugal blower,
The housing includes a mounting hole,
The centrifugal blower is provided with a projection display device that is fixed to the housing in a state where the second casing is fitted in the mounting hole.

According to yet another aspect of the present invention,
A housing containing a heat source;
The centrifugal blower,
The housing includes a mounting hole,
The centrifugal blower is provided with an electronic device that is fixed to the casing in a state where the second casing is fitted in the attachment hole.

  ADVANTAGE OF THE INVENTION According to this invention, the exhaust-cooling effect of the housing | casing which has a complicated internal structure can be heightened, and the part which protrudes to the outer side of a housing | casing can be made small.

It is a perspective view which shows typically the structure of the centrifugal air blower by one Embodiment of this invention. It is an exploded view which shows typically each component of the centrifugal air blower shown in FIG. It is a perspective view which shows typically the housing inside of the apparatus provided with the centrifugal air blower shown in FIG.1 and FIG.2.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view schematically showing a configuration of a centrifugal blower according to an embodiment of the present invention. FIG. 2 is an exploded view schematically showing each component of the centrifugal blower shown in FIG.
As shown in FIGS. 1 and 2, the centrifugal blower includes a disk 3a in which a plurality of blades 5 are provided in the circumferential direction, and the rotation of the disk 3a causes intake air in the direction of the rotation shaft 6. It has an impeller 3 that is exhausted in the centrifugal direction.

The impeller 3 includes a motor 4 for rotating the disk 3a. The motor 4 includes a shaft that supports the central portion of the disk 3a, and rotates the disk 3a by rotating the shaft. A straight line passing through the center of the shaft of the motor 4 is the rotation shaft 6. Since the structure of the built-in motor 4 is well known, the description thereof is omitted here (for example, Patent Document 1 and Patent Document 2 also describe a similar motor structure).
For the impeller 3, a configuration of an impeller of a centrifugal fan represented by a sirocco fan or a turbo fan can be applied. Here, the configuration of an impeller of a sirocco fan is applied. Specifically, each of the plurality of blades 5 is provided perpendicular to the surface of the disc 3a, and the end farther from the center of the disc 3a with respect to the rotation direction is closer to the center of the disc 3a. The angle is set so as to be located on the front side of the end portion of.

The impeller 3 is accommodated in the casing 7. The casing 7 includes a lower casing 9 to which the impeller 3 is fixed, and a cup-shaped upper casing 8 that houses the impeller 3 fixed to the lower casing 9. The upper casing 8 includes an air inlet 12 at a portion intersecting with the direction of the rotation axis 6. Air flows into the impeller 3 along the direction of the rotation axis 6 through the intake port 12.
The upper casing 8 has a cylindrical inclined wall 8 a composed of a plurality of surfaces surrounding the outer periphery of the impeller 3. The inclined wall 8a is configured such that the inner diameter increases as the distance from the inlet 12 in the direction of the rotation axis 6 increases. The inclination angle of each surface of the inclined wall 8a with respect to the rotation shaft 6 can be set as appropriate. The number of surfaces of the inclined wall 8a can be set as appropriate.
The inclined wall 8a may be cylindrical. Also in this case, the inner diameter of the inclined wall 8a increases as the distance from the air inlet 12 in the direction of the rotation axis 6 increases.

An annular exhaust port 13 is formed by the outer peripheral end portion of the lower casing 9 and the outer peripheral end portion of the upper casing 8. The air exhausted in the centrifugal direction by the impeller 3 flows along the inclined wall 8a, and is then discharged from the casing 7 through the exhaust port 13. Since the impeller 3 can exhaust air over the entire circumference (360 °), the resistance on the exhaust side is smaller than that of the centrifugal fan in which the casing is configured to blow out air in one direction.
The resistance on the exhaust side changes according to the inclination angle of the inclined wall 8a. As the inclination angle increases, the resistance on the exhaust side decreases, and as a result, the air volume increases. However, the larger the tilt angle, the larger the device.

The lower casing 9 is fixed to a portion of the upper casing 8 where the air inlet 12 is formed via a plurality of studs (鋲) 11 and a plurality of annular plates 10. The outer shape of each plate 10 and the outer shape of the lower casing 9 substantially coincide with each other, and the portion composed of the lower casing 9 and the two plates 10 is cylindrical. The impeller 3 is accommodated in this cylindrical portion, and the two plates 10 have a structure that prevents a structure such as a finger from coming into contact with the rotating portion of the impeller 3 (the portion of the blade 5). It has become.
In addition, in the example of FIG.1 and FIG.2, although the two plates 10 are used, it is not limited to this. One or a plurality of plates 10 can be used. As the number of the plates 10 increases, the gap becomes narrower, so that it is possible to more reliably prevent the structure such as a finger from contacting the rotating portion of the impeller 3. However, since the plate 10 has resistance on the exhaust side, it is desirable to determine the number of the plates 10 in consideration of a decrease in the air volume.
A first surface that is the surface opposite to the surface on which the impeller 3 of the lower casing 9 is fixed, and an opening surface formed by the outer peripheral end of the upper casing 8 (opening surface of the cylindrical inclined wall 8a). The second surface is preferably parallel to the second surface. In this case, it is desirable that the height of the first surface from the intake port 12 in the direction of the rotation axis 6 is equal to or less than the height of the second surface from the intake port 12 in the direction of the rotation axis 6.

According to the centrifugal air blower of the present embodiment described above, since it has a feature that the static pressure is high like a general centrifugal fan, even if the internal structure of the housing is complicated, the air in the housing is efficiently exhausted. can do. Further, since the resistance on the exhaust side is small compared to a general centrifugal fan in which the casing is configured so that air blows out in one direction, the air volume can be increased. Therefore, a high exhaust cooling effect can be obtained even in a housing having a complicated internal structure.
In the centrifugal blower of the present embodiment, the upper casing 8 on the intake side has a cup-like structure, and the impeller 3 is accommodated in the upper casing 8. According to this structure, when the centrifugal blower is attached to the casing, the upper casing 8 accommodating the impeller 3 can be fitted into the mounting hole of the casing, so that the centrifugal blower protrudes outside the casing. The portion to be made can be made small, or the protruding portion can be completely eliminated.

FIG. 3 is a perspective view schematically showing the inside of the housing of the apparatus provided with the centrifugal blower shown in FIGS. 1 and 2.
Referring to FIG. 3, the device 1 is an electronic device or a projection display device, and includes a housing 1 a and a centrifugal blower 2. The centrifugal blower 2 has the structure shown in FIGS.
The housing 1a includes a mounting hole 1b. The attachment hole 1b is configured so that the entire upper casing 8 can be fitted therein. The centrifugal blower 2 is fixed to the housing 1a in a state where the casing 8 is fitted in the mounting hole 1b.

The impeller 3 sucks air in the housing 1a through the air inlet 12, and exhausts the sucked air out of the housing 1a. In FIG. 3, an arrow A indicated by a solid line indicates a flow of air sucked into the impeller 3 through the intake port 12, and an arrow B indicated by a broken line indicates a flow of air exhausted from the impeller 3. . For convenience, the direction of exhaust gas indicated by the four arrows B is about 180 °, but is actually 360 °.
The first surface, which is the surface opposite to the surface on which the impeller 3 of the lower casing 9 is fixed, is an opening surface (opening surface of the inclined wall 8 a) formed by the outer peripheral end of the upper casing 8. The plane of 2 is parallel. The height of the first surface from the inlet 12 in the direction of the rotation axis 6 is equal to or lower than the height of the second surface from the inlet 12 in the direction of the rotation axis 6. When the height from the air inlet 12 in the direction of the rotation axis 6 of the surface where the mounting hole 1b of the housing 1a is formed is the same as that of the second surface, the centrifugal blower projects out of the housing 1a. There is nothing.

When the device 1 is an electronic device, the housing 1a accommodates a plurality of components that constitute the electronic device. At least one of these parts is a heat source.
When the device 1 is a projection display device, the housing 1a accommodates a plurality of components that constitute the projection display device. For example, the housing 1a accommodates a light source, an image forming unit that spatially modulates light from the light source to form an image, and a projection optical system that projects the image.
In addition, in the example of FIG. 3, although the centrifugal air blower 2 is provided in the bottom face of the housing | casing 1a, this invention is not limited to this. Centrifugal blower 2 may be attached to any surface of case 1a.

DESCRIPTION OF SYMBOLS 1 Apparatus 1a Case 1b Mounting hole 2 Centrifugal blower 3 Impeller 3a Disc 4 Motor 5 Blade 6 Rotating shaft 7 Casing 8 Upper casing 8a Inclined wall 9 Lower casing 10 Plate 11 Stud 12 Inlet 13 Exhaust

Claims (7)

An impeller in which a plurality of blades are provided with a circular plate provided in the circumferential direction, and the circular plate rotates so that intake is performed in the rotation axis direction and exhaust is performed in the centrifugal direction;
A first casing to which the impeller is fixed;
A second casing that houses the impeller fixed to the first casing;
The second casing includes a first opening for performing the intake at a portion intersecting the rotation axis direction,
The centrifugal air blower in which the outer peripheral end of the first casing and the outer peripheral end of the second casing form an annular second opening for performing the exhaust. The centrifugal blower according to claim 1,
A first surface that is a surface opposite to a surface to which the impeller of the first casing is fixed, and a second surface that is an opening surface formed by an outer peripheral end portion of the second casing. Are parallel to each other, and the height of the first surface from the first opening in the direction of the rotation axis is equal to or less than the height of the second surface from the first opening in the direction of the rotation axis. , Centrifugal blower. In the centrifugal air blower according to claim 1 or 2,
The second casing has a cylindrical inclined wall surrounding the outer periphery of the impeller, and the inner diameter of the inclined wall increases as the distance from the first opening side in the rotation axis direction increases. The centrifugal blower configured in the above. In the centrifugal air blower according to any one of claims 1 to 3,
The centrifugal blower further comprising at least one annular plate that is supported between the first and second casings and surrounds an outer periphery of the impeller. In the centrifugal air blower according to any one of claims 1 to 4,
Each of the plurality of blades is provided perpendicular to the surface of the disk, and the end farther from the center of the disk than the end closer to the center of the disk with respect to the rotation direction. A centrifugal blower in which the angle is set to be located on the front side. A housing that houses a light source, an image forming unit that spatially modulates light from the light source to form an image, and a projection optical system that projects the image;
A centrifugal blower according to any one of claims 1 to 5,
The housing includes a mounting hole,
The centrifugal blower is a projection type display device that is fixed to the casing in a state in which the second casing is fitted in the mounting hole. A housing containing a heat source;
A centrifugal blower according to any one of claims 1 to 5,
The housing includes a mounting hole,
The centrifugal air blower is an electronic device that is fixed to the housing in a state in which the second casing is fitted in the mounting hole.

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