JPH11243667A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a fan that is sopped by a rollback wind pressure form being rotated in reverse direction, by providing a fan for cooling electronic parts being arranged in an enclosure, and achieving structure for escaping an inverse rotary force. SOLUTION: Each blade 24 is divided into two portions along a line that is extended toward the outside in a radius direction from a shaft 22 and is provided with a fixed blade part 24a and a movable part 24b. The fixed blade part 24a and the movable blade part 24b are connected by a hinge shaft 24c. Also, the movable blade part 24b is provided with a fixed projection 24d for fixing blade part 24b at a proper position while a fan 20 is rotating, thus enabling the fixed blade part 24a and the movable part 24b to operate as one complete 24 while the movable blade part 24b is in contact with the fixed projection 24d of the fixed blade part 24a when the fan 20 rotates clockwise during operation and hence obtaining an optimum amount of wind. When the fan 20 stops, rollback wind is given as a force for forcing the movable blade part 24b down. Then, by forcing the movable blade part 24b down, a force for inducing a reverse rotation can be made to escape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device such as a telephone exchange.

[0002]

2. Description of the Related Art At present, in electronic devices, since electronic components disposed inside a housing generate heat, a cooling device is provided for cooling. The cooling of electronic devices is roughly classified into liquid cooling and air cooling. Generally, liquid cooling has a greater cooling effect than air cooling, but liquid cooling is more complex than air cooling, which avoids the cost increase of liquid cooling and the difficulty of maintenance. Absent. Also, in the liquid cooling structure, water droplets (moisture) adhere to the circulation pipe and other parts of the device and cause an electrical failure. Therefore, it is necessary to avoid such an influence in the initial design study stage. It is necessary to keep.

[0003] Therefore, in an electronic device such as a telephone exchange which needs to maintain a long life and high durability, a forced air cooling system is often applied. However, in recent electronic devices, the electronic components are downsized and driven at a low voltage, and many electronic components are accommodated in one unit. 1
As the number of electronic components per unit increases, overall heat generation of the electronic device is higher than in previous systems. In order to cover this with forced air cooling, it is always necessary to increase the size of the fans or increase the number of fans.

[0004] A plurality of fans are arranged in the electronic device, and the air generated by these fans travels along a predetermined cooling air passage and is discharged from the electronic device. Generally, the wind due to forced air cooling is always removed in the direction opposite to the operating direction or toward the ceiling so as not to give an uncomfortable feeling to the operator. In addition, if there is a device to be cooled in the immediate vicinity of the fan, there is a problem with the flow of the cooling air or there is a problem that the device to be cooled is not sufficiently cooled. The cooling condition is not arranged, and a design condition is provided so that a predetermined space is provided between the outlet of the fan and the device to be cooled.

In general, inexpensive axial fans are used as forced air cooling fans. However, in the case of an axial fan, a satisfactory air volume (wind velocity) can be obtained directly above the fan blades, but a satisfactory result cannot be obtained immediately above the fan shaft. In order to obtain a sufficient air volume (wind speed) even just above the axis of the fan, it is necessary to have a certain distance from the fan. As a result, the wind generated by the fan blades is agitated, and the cooling effect is generated even immediately above the fan shaft.

[0006]

In designing an electronic device, it is necessary not only to make electronic components compact, but also to make the housing compact. To that end, it is desirable to reduce the volume occupied by the cooling device. But,
As described above, when arranging electronic components on the upstream side in the blowing direction of the fan, a certain distance is required between the fan and the device to be cooled. In order to make the housing compact, it is necessary to make this interval as small as possible. In this case, the device to be cooled directly above the fan shaft has a higher temperature rise than directly above the blades of the fan. Can be considered. However, in this case, it is easily conceivable that the pattern design or the component arrangement makes it impossible or requires additional components.

[0007] The air volume generated by the fans increases due to the increase in size and the number of units, but if the air volume is not exhausted from the system without stress, some fans generate rewinding air pressure due to the air pressure of other fans. At the time of maintenance of the fan, the rotation of the fan is naturally stopped. At this time, the fan stopped by reverse wind pressure may cause reverse rotation, and the maintenance person may be injured at the time of maintenance. Therefore, it is desired that when the fan is stopped, the fan can be prevented from being reversely rotated by the rewinding wind pressure.

[0008] It is an object of the present invention to provide an electronic device capable of preventing reverse rotation of a fan stopped by a rewinding wind pressure. Another object of the present invention is to
It is an object of the present invention to provide an electronic device capable of increasing the amount of cooling air without increasing the space of the cooling device. Another object of the present invention is to provide an electronic device capable of reducing a torque at the time of starting a fan.

[0009]

Means for Solving the Problems To solve the above problems, it is only necessary to change the high heat generating device to lower heat generation. However, it is very difficult to consolidate functions and counter the trend of reducing costs. The reverse rotation of the fan must be avoided even if the air volume obtained by the forced air cooling is reversed due to an obstacle or the like directly above the fan. Although a method of increasing the torque of the fan motor is conceivable, the diameter of the shaft portion increases. In other words, if the size of the fan unit is fixed, the area allocated to the blades is reduced, which causes a decrease in air volume. Further, if the number of rotations is increased to compensate, the life of the fan motor may be shortened.

Therefore, the wind pressure for generating the reverse rotation is not used as the rotation force of the fan. In short, the structure for releasing the rotation force makes it possible to cope with the wind pressure for generating the reverse rotation while maintaining the current state of the motor performance. . That is, an electronic device according to one aspect of the present invention includes a housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, and the fan has a reverse rotation prevention structure. It is characterized by the following.

An electronic device according to one aspect of the present invention includes a housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, wherein the fan has a reverse rotational force. It is characterized by having a structure to escape.
In these aspects, the blades of the fan may be configured to have a flip structure. That is, the blades of the fan are composed of the fixed blades and the movable blades, and the movable blades are moved with respect to the fixed blades, thereby preventing reverse rotation and releasing reverse rotation force.

As a method of increasing the cooling capacity just above the fan shaft, attention is paid to the fact that the fan blades are fixed to the shaft, so that the shaft is also rotating, and fins are added to the shaft. Thus, it is possible to generate a cold flow just above the axis. That is, an electronic device according to one aspect of the present invention includes a housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, wherein the fan includes a rotating shaft, It is characterized by comprising a blade provided on the rotating shaft and a sub-fan provided on the rotating shaft to improve the cooling capacity.

[0013] An electronic device according to one aspect of the present invention includes a housing, an electronic component disposed in the housing, and a fan for cooling the electronic component. And a blade provided on the rotating shaft, and a sub-fan provided on the rotating shaft, wherein wind power is generated just above the shaft. Therefore, even when the gap to the heating element on the shaft is small, it is possible to blow air.

When the sub-fan is mounted in a direction opposite to the above-mentioned purpose, the above-described reverse-rotating wind pressure is converted into a normal rotational force, and can be used as an auxiliary force when starting the stopped fan. That is, an electronic device according to one aspect of the present invention includes a housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, wherein the fan includes a rotating shaft, It is characterized by comprising a blade provided on a rotating shaft and a sub-fan provided on the rotating shaft to supplement a starting mechanism at the time of starting the fan.

These configurations are very effective when there is an unavoidable obstacle in the exhaust passage due to the housing structure.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, an electronic device 10 according to an embodiment of the present invention is an example of a telephone exchange package. The electronic device 10 includes vertically arranged shelves 14.
(Cabinet) 12 having A plurality of electronic components 16 to which a printed circuit board or the like is attached are inserted into each shelf 14. Connectors are provided at the ends of the electronic components 16 in the insertion direction, and these connectors are adapted to be fitted with connectors provided on the back board of the housing 12.

The electronic device 10 further includes a fan shelf 18.
For example, the fan shelves 18 are arranged above the respective shelves 14, and cool the electronic components 16 by cooling air blown by the fan 20 of the fan shelves 18, and the cooling air is cooled by the housing 12 as shown by the arrow A.
It is designed to be exhausted upward from above. FIG. 2 is a diagram illustrating an example of the fan 20. The fan 20 includes a shaft 22 and
And a plurality of blades 24 attached to the shaft 22. Further, the rotation shaft of the fan motor 26 is connected to the shaft 22. FIG. 2 is a side view of a simplified axial fan drawn from the side.

When the fan motor 26 rotates clockwise, the shaft 22 and the blades 24 rotate similarly, and this rotation generates wind upward as indicated by the arrow B. In order to perform maintenance of the fan 20 from this state, the fan 20 is stopped, and if there is an obstacle in the air path, the static pressure immediately above the stopped fan 20 is reduced, and the direction of air blowing is reduced by the obstacle. A wind in the opposite direction (rewinding wind) is generated, and the blade 24 is induced to rotate in a direction opposite to the rotation direction exerted by the fan motor 26, and the reverse rotation generates wind in the direction of a dotted arrow (arrow C).

Due to this reverse rotation, when performing maintenance on the fan 20, when the fan 20 is pulled out from the housing 12, the fan 20 is pulled out while being rotated in the reverse direction.
There is a risk of causing an accident. Therefore, if it is not possible to remove the rewinding wind due to the structure of the housing 12, the stopped fan 2
It is desirable that 0 does not reversely rotate due to the wind.

Therefore, as shown in FIGS. 3 and 4, the structure of the blades 24 is worked, and the blades 24 are divided to have a flip structure, so that the fan 20 has a reverse rotation preventing structure. I have to. Each blade 24 has a shaft 2
2 are divided into two along a line extending outward in the radial direction, and have a fixed blade portion 24a and a movable blade portion 24b. The fixed blade portion 24a and the movable blade portion 24b are hingedly connected by a hinge shaft 24c. In order to fix the movable blade portion 24b at a regular position while the fan 20 is rotating, the fixed blade portion 24b is fixed.
a has a fixing protrusion 24d.

With this configuration, when the fan 20 rotates clockwise during operation, the movable blade portion 24b contacts the fixed protrusion 24d of the fixed blade portion 24a, and the fixed blade portion 24a and the movable blade portion 24b are separated. Acting as one complete blade 24, an optimum air volume is obtained. When the fan 20 is stopped, the rewinding wind is applied as a force for lowering the movable blade portion 24b downward, and a force that induces reverse rotation due to the falling of the movable blade portion 24b is released.

With this structure, the possibility of the fan 20 rotating during maintenance is extremely low. In the maintenance process, the fuse of the fan 20 is removed, and the current to the fan motor 26 is cut off. Within a short time to remove the fan 20, the fan 20 stops and the fan 20 can be safely removed. FIG.
FIG. 8 is a view showing another embodiment of the present invention. In this embodiment, the blades 24 are fixed to the shaft 22 due to the structure of the axial flow fan 20, so that when the fan 20 rotates, the shaft 22
Also, attention is paid to the fact that the fan is also rotating, and a fan structure is provided on the shaft 22 to avoid the drawbacks of the axial fan that cannot supply air satisfactorily. In the structure of the general axial flow fan 20, the wind generated by the blades 24 can be used immediately above the blades 24, but the wind generated by the blades 24 cannot be sufficiently used directly above the shaft 22, and It is a well-known fact that the wind generated by the blades 24 is agitated when a certain distance (a certain distance from the shaft 22) is attained, and the wind also occurs immediately above the shaft 22.

Therefore, in terms of design, an air reservoir (hereinafter referred to as a space) is provided immediately above the fan 20 to avoid the drawbacks of the axial fan in terms of the design conditions of the apparatus. However, providing sufficient space increases the external dimensions of the electronic device 10. Therefore, if the space can be reduced to overcome the drawbacks of the axial fan, the electronic device 10 can be further reduced in size, and the capability of forced air cooling can be improved.

FIG. 5 shows the structure of a fan invented to reduce the space. A sub-fan 30 is additionally attached to the blade 24 at the tip of the shaft 22 of the fan 20. The auxiliary fan 30 is smaller than the blade 24,
Has a size approximately equal to the diameter of The auxiliary fan 30 is mounted on the shaft 2 of the fan 20 by a suitable fixing means such as a screw or an adhesive.
2 attached.

As shown in FIGS. 6 and 7, the shape of the sub-fan 30 is conical and has blades 32 extending obliquely along the conical surface. The blade 32 has a shape protruding outside the diameter of the shaft 22, and has a structure in which air is collected at this difference portion. In addition, by forming the blade 32 in a spiral shape, an air volume can be added to the wind generated by the blade 24, and the wind generated by the blade 24 is generated immediately above the shaft 22 by a spiral flow generated by the blade 32. The cooling air can be used just above the shaft 22. Therefore, the space between the fan 20 and the device to be cooled can be reduced, and the housing 12 of the electronic device 10 can be made compact.

FIG. 8 is a view showing a fan unit in which the fan 20 is disposed in the fan case 32. The fan case 32 has a hole therethrough, and the fan 20 and the fan motor 26 are housed in the hole so as to be able to blow air. A wire mesh finger 34 is attached to the fan case 32. Fingered 34 projects upward,
Usually, there is a gap between the shaft 22 and the tip. Therefore, even if the sub-fan 30 is attached to the tip of the shaft 22, the sub-fan 30 fits in the fingered 34, and there is no need to change the size of the fan unit.

FIG. 5 shows another embodiment of the present invention.
In the configuration shown in FIG. 8, the spiral direction of the blade 32 is set to the opposite direction, and the blade 32 is used in combination with the above-mentioned hinged blade, so that the fan motor 26 is energized at the end of maintenance, and a rotational torque is generated in the fan motor 26. When you do
It serves as some auxiliary power, which has the effect of reducing the inrush current of the fan.

[0028]

As described above, according to the present invention,
Providing a reverse rotation prevention mechanism, realizing space saving, improving the forced air cooling capacity immediately above the shaft, and reducing the initial current by improving the starting force (torque) can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an electronic device to which the present invention is applied.

FIG. 2 is a side view showing the fan of FIG. 1;

FIG. 3 is a plan view of the fan of FIG. 2;

4 is a cross-sectional view of the fan of FIG. 3 taken along line IV-IV.

FIG. 5 is a side view showing a fan according to a second embodiment of the present invention.

FIG. 6 is a side view of the sub fan of FIG. 5;

FIG. 7 is a plan view of the sub fan of FIG. 5;

FIG. 8 is a diagram showing a fan unit in which a fan is arranged in a fan case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Electronic device 12 ... Housing 16 ... Electronic components 18 ... Fan shelf 20 ... Fan 22 ... Shaft 24 ... Blade 30 ... Sub fan 32 ... Blade

Claims (6)

[Claims] 1. An electronic device comprising: a housing; an electronic component disposed in the housing; and a fan for cooling the electronic component, wherein the fan has a reverse rotation preventing structure. 2. An electronic device comprising: a housing; an electronic component disposed in the housing; and a fan for cooling the electronic component, wherein the fan has a structure for releasing a reverse rotation force. apparatus. 3. The electronic device according to claim 1, wherein the blades of the fan have a flip structure. 4. An electronic apparatus comprising: a housing; an electronic component disposed in the housing; and a fan for cooling the electronic component, wherein the fan includes a rotating shaft, and a blade provided on the rotating shaft. An electronic device comprising a sub-fan provided on the rotating shaft to improve the cooling capacity. 5. A housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, the fan comprising: a rotating shaft; and a blade provided on the rotating shaft. An electronic device, comprising: a sub-fan provided on the rotating shaft to generate wind power immediately above the shaft. 6. A housing, an electronic component disposed in the housing, and a fan for cooling the electronic component, the fan comprising: a rotating shaft; and a blade provided on the rotating shaft. And an auxiliary fan provided on the rotating shaft, so as to supplement a starting mechanism at the time of starting the fan.