JP3552643B2 - Cooling fan in electrical equipment - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cooling fan used for an electric device, for example, a communication device or a personal computer, for cooling the device by discharging warm air inside to the outside.
[0002]
[Prior art]
In general, in electrical equipment such as communication devices and personal computers, the units used have been increased in speed and density, and the power consumption has also increased accordingly. Therefore, the conventional natural air cooling system using convection of air is not sufficient. The temperature inside the unit exceeds the guaranteed temperature range for device operation on the PKG due to heat generated by the electronic circuit package (hereafter referred to as PKG) mounted on the unit due to insufficient cooling, which may cause malfunction or failure. In order to provide the above, an example of using a forced air cooling system in which a cooling fan is mounted and a device on the PKG is cooled by an air flow generated by rotation of the cooling fan has been increasing.
Conventionally, the cooling fan used in such electric equipment has multiple blades fixed at an optimal angle so that air can be sent efficiently by rotating around the fan rotation axis, and the blades are surrounded and protected. The casing is formed as shown in FIG.
When this cooling fan is used in a system, it is mounted on the top of the heat generating unit so that the heat generated by the devices mounted on the PKG can be sufficiently cooled, and the air warmed by the unit is sucked in and discharged to the outside of the electrical equipment The method is adopted.
[0003]
[Problems to be solved by the invention]
By the way, the substantial gap between the PKGs mounted on the unit is a dimension obtained by subtracting the thickness of the printed circuit board and the height of the mounted parts on the PKG from the mounting pitch of the PKG, and there is only a very small amount. Although it is difficult to pass, even if the ventilation resistance is somewhat higher if the gaps are arranged evenly, the wind can evenly pass between the PKGs and cool the devices on the PKGs.
The first problem with such a conventional cooling fan is that when the fan unit is mounted above the heating unit, if the fan fails and the rotation stops, the blades of the failed fan will This causes heat to be trapped in the heat generating unit, which may cause malfunction or failure of a device mounted on the PKG in the unit.
[0004]
An object of the present invention is to provide a structure for dissipating heat of an electronic circuit package mounted in an electric device even when a cooling fan fails, thereby preventing malfunction and destruction of devices on the electronic circuit package. And
[0005]
[Means for Solving the Problems]
The cooling fan in the electric device according to claim 1 of the present invention is a cooling fan that is mounted on the electric device and discharges air inside the electric device to the outside, in order to achieve the above-described object, A casing, a rotating body rotatably mounted in the casing, and a plurality of rotating blades mounted on the rotating body, and these rotating blades slide on the rotating body in the direction of the radius of rotation thereof. The rotating body is formed so as to be hollow, and each of the rotating blades is slidably penetrated through a peripheral wall of the rotating body .
A cooling fan in the electrical device according to claim 2 of the present invention, the respective rotary blade according to claim 1, in a portion positioned in the rotating body, by being brought into contact with the inner surface of the rotary body And a stopper for restricting a position of each of the rotating blades protruding from the rotating body.
A cooling fan in the electrical device according to claim 3 of the present invention is the rotating body of claim 1, the elastic member that acts to draw the respective rotary blades to the inside of the rotating body is provided It is characterized by the following.
A cooling fan in the electrical device according to claim 4 of the present invention, the electric device according to claim 1, characterized in that it is a communication device.
The cooling fan according to claim 5 of the present invention, wherein the electric device according to claim 1 is a personal computer.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a vertical cross-sectional view showing a state in which a cooling fan according to the present embodiment is rotating normally. In this figure, a cooling fan indicated by a symbol F is a cylindrical fan mounted on an electric device (not shown). A rotating body 3 which is coaxially and rotatably mounted in the casing 1 and forms an air passage 2 between the casing 1 and a wall surface without the casing 1; And a plurality of rotary blades 4 slidably mounted along the air passage 2 and provided to be able to advance and retreat with respect to the air passage 2.
[0007]
Next, the details will be described. In the present embodiment, the rotating body 3 is formed in a hollow shape, and a spindle shaft 5 rotatably supported by the casing 1 is provided at an axial center position thereof. The rotating body 3 is rotatably supported by the casing 1 via the spindle shaft 5.
[0008]
Further, through holes 6 are formed radially in the circumferential wall portion of the rotating body 3 along the rotation radial direction, and the rotating blades 4 are slidably mounted in these through holes 6. .
[0009]
The rotating blade 4 is integrally provided with a stopper 7 that restricts a projecting position of the rotating blade 4 by being brought into contact with an inner surface of the rotating member 3 at an end located inside the rotating member 3. ing.
[0010]
Further, an elastic member 8 is provided inside the rotating body 3 for connecting the rotating blades 4 to the spindle shaft 5 and for urging the rotating blades 4 in a direction of drawing the rotating blades 4 into the rotating body 3. Have been.
[0011]
A motor (not shown) is connected to the spindle shaft 5 so as to rotate the rotating body 3 and the rotating blades 4 together with the spindle shaft 5.
Further, the urging force of the elastic member 8 shown by the arrow A in FIG. 2 is set smaller than the centrifugal force (indicated by the arrow B in FIG. 1) acting on each of the rotating blades 4 with the rotation of the rotating body 3. Have been.
[0012]
Next, the operation of the cooling fan F according to the present embodiment thus configured will be described.
First, when the cooling fan F is operating normally, the rotating body 3 is driven to rotate, and centrifugal force acts on each of the rotating blades 4 mounted on the rotating body 3, so that the centrifugal force is applied. By the force, each rotating blade 4 is moved so as to protrude outside the rotating body 3 against the urging force of the elastic member 8.
The projecting positions of the rotary blades 4 are regulated as shown in FIG. 1 by the stoppers 7 attached to the rotary blades 4 being brought into contact with the inner surface of the rotary body 3.
Each of the rotating blades 4 protruded to a predetermined position in this manner is rotated by the rotation of the rotating body 3, so that air inside the device (not shown) is taken into the casing 1. Release from the casing 1 to the outside.
This suppresses a rise in temperature inside the device.
[0013]
On the other hand, when the cooling fan F stops due to a failure or the like, the rotation of the rotating body 3 and the rotating blades 4 is stopped.
When the rotation of the rotary blades 4 is stopped, the centrifugal force B acting on the rotary blades 4 disappears, and the rotary blades 4 are rotated by the urging force A of the elastic member 8. It is drawn into the body 3.
As a result, the air passage 2 formed between the casing 1 and the rotating body 3 is opened as shown in FIG.
As a result, the air warmed in the device immediately below the cooling fan F flows to the outside through the air passage 2 without being obstructed by the rotating blades 4, and therefore, the heat generated from the entire PKG portion in the device. All of them are not kept in the unit, so that the temperature rise of the whole PKG portion can be suppressed, and the failure or destruction of the device due to the temperature rise can be prevented.
[0014]
Note that the shapes, dimensions, and the like of the respective constituent members shown in the above embodiment are merely examples, and can be variously changed based on design requirements and the like.
[0015]
【The invention's effect】
Since the present invention is configured as described above, when the cooling fan is operating normally, the rotating blades are protruded into the air passage to perform forced exhaust, and also to cool down due to a failure or the like. When the fan stops, the air passage can be largely opened by the rotatable blades being housed in the rotating body, thereby enabling natural convection to exhaust.
Therefore, the temperature inside the device can be suppressed from rising during normal operation or failure, and the soundness of the electronic elements inside the device can be ensured.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention and showing a normal operation state.
FIG. 2 shows one embodiment of the present invention, and is a longitudinal sectional view showing a stop mode.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Casing 2 Air passage 3 Rotating body 4 Rotating blade 5 Spindle shaft 6 Through hole 7 Stopper 8 Elastic member F Cooling fan

Claims (5)

A cooling fan mounted on an electric device and configured to discharge air inside the housing to the outside, comprising a casing, a rotating body rotatably mounted in the casing, and a plurality of rotating bodies mounted on the rotating body. These rotating blades are attached to the rotating body so as to be slidable in the rotation radial direction, and the rotating body is formed in a hollow shape, and each of the rotating blades is A cooling fan in an electric device, wherein the cooling fan is slidably penetrated through a peripheral wall of the rotating body . A stopper is provided at a position of each of the rotating blades, which is located in the rotating body, so as to be in contact with an inner surface of the rotating body, to regulate a projecting position of each of the rotating blades from the rotating body. The cooling fan according to claim 1, wherein the cooling fan is provided. 2. The cooling fan according to claim 1, wherein the rotating body is provided with an elastic member that acts to draw each of the rotating blades into the inside of the rotating body. 3. The cooling fan according to claim 1, wherein the electric device is a communication device. The cooling fan according to claim 1, wherein the electric device is a personal computer.

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