JPH1041661A - Electronic apparatus cooling structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the spread of the mounting spacing and noise of cooling fans to reduce the thermal resistance by mounting a local cooling fan at an opening of a fan mounting plate opened at a position corresponding to circuit elements in the same rack as a wiring board and entire cooling fan at the upper and lower side face of the rack. SOLUTION: Integrated circuit elements 1 are mounted on a wiring board 2. A local cooling fan 3 is mounted on a fan mounting plate 4 with cables 5 and fan control circuit 6. The fan 3 is mounted at a position facing the elements 1 on the adjacent board 2. The mounting plate 4 has an opening corresponding to the blades of the fan 3. A partition 8 is disposed between this side and upper side of the plate 4. The wiring boards 2 and fan mounting plates 4 are housed and mounted vertically in a rack 9. An entire cooling fan 10 is disposed on the upper or lower side of the rack 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling structure for electronic equipment, and more particularly, to a cooling structure for electronic equipment in which a plurality of wiring boards on which circuit elements such as integrated circuits are mounted are mounted.

[0001]

2. Description of the Related Art As shown in FIG. 5, a conventional cooling structure for an electronic device is such that a plurality of wiring boards on which integrated circuit elements are mounted are housed in a frame and a cooling fan 17 is installed at one or both ends of the frame. A configuration is adopted in which cooling is performed using forced convection of air. That is, the conventional cooling structure includes an integrated circuit element 14 and a wiring board 15 on which the integrated circuit element 14 is mounted.
And a frame 16 for accommodating a plurality of wiring boards 2, and a cooling fan 17. When the cooling fan 17 rotates, forced convection of air occurs from the top to the bottom of FIG. Cooling the integrated circuit element 14 on 15.

When the power consumption of the integrated circuit element is large, a heat sink 18 is attached to increase the heat transfer area between the air and the air, or the wind speed of the cooling fan 17 is increased to increase the air flow from the integrated circuit element 14 to the air. To keep the temperature of the element low. In recent years, a configuration in which a small cooling fan and a heat sink are integrated and attached to an integrated circuit element to locally increase the wind speed to perform cooling has been adopted.

[0003]

The conventional cooling structure has a first problem that when the power consumption of the integrated circuit element increases, the heat sink must be increased, leading to a decrease in the performance of the device.

[0004] The reason is that, in order to increase the surface area of the heat sink and reduce the thermal resistance, when the height is increased in the height direction, the mounting intervals of the wiring boards are increased, and when the length is increased in the length direction or the width direction, In a device such as a high-speed computer where the signal delay due to wiring affects the performance, the wiring length between different wiring boards and components becomes longer because the distance between other components on the same wiring board is widened. is there.

Further, in the conventional cooling structure, avoiding the first problem and increasing the wind speed of the cooling fan to reduce the thermal resistance without changing the size of the heat sink leads to an increase in noise. There is a second problem.

The reason for this is that it is necessary to increase the size of the fan or increase the rotation speed in order to increase the wind speed.

In the conventional cooling structure, when a heat sink with a fan in which a small fan and a heat sink are integrated is used, the third problem is that the power supply system becomes complicated and the system cannot cope with non-stop operation. There is also.

[0008] The reason is that power for the fan must be supplied by a wiring board or an external cable. If the fan fails, it is necessary to cut off the power supply of the apparatus, remove the wiring board, and replace it. Because there is.

An object of the present invention is to provide a cooling structure for an electronic device which solves the above-mentioned problems.

[0010]

A cooling structure for electronic equipment according to the present invention has an opening at a position facing a circuit element on an adjacent wiring board which is housed on the same frame as a plurality of wiring boards on which circuit elements are mounted. It is composed of a fan mounting plate, a local cooling fan mounted at an opening position of the fan mounting plate, and an overall cooling fan mounted on at least one of the upper, lower and side surfaces of the rack.

[0011]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view thereof. A heat sink for heat radiation is attached to the integrated circuit element 1. The integrated circuit element 1 is mounted on a wiring board 2. This embodiment further includes a local cooling fan 3 and a local cooling fan 3.
, A fan mounting plate 4, a cable 5, and a fan control circuit 6. Here, the local cooling fan 3 is connected to the integrated circuit element 1 on the wiring board 2 adjacent to the fan mounting plate 4.
The fan mounting plate 4
The opening 7 is provided at a portion corresponding to the wing portion of the local cooling fan 3.
There is. Further, partitions 8 are provided on the front side and the upper side of the fan mounting plate 4. The plurality of wiring boards 2 and the fan mounting plate 4 are accommodated in a frame 9, and the wiring board 2 and the fan mounting plate 4
And are implemented vertically. Furthermore, the whole cooling fan 1
0 are provided above and below the rack 9. The fan 10 may be located only above or below the rack 9.

The cooling air from the overall cooling fan 10 is
Flows through the space between the wiring boards 2 accommodated in the wiring board (indicated by solid arrows in FIG. 2), and cools the integrated circuit element 1 on the wiring board 2. On the other hand, the air flowing into the air between the fan mounting plate 4 and the adjacent wiring board 2 on the side where the local cooling fan 3 is mounted by the overall cooling fan 10 is transmitted from the opening 7 of the fan mounting plate 4 by the local cooling fan 3. It is blown perpendicularly to the integrated circuit element 1 on the adjacent wiring board 2 on the side opposite to the local cooling fan 3 mounting surface (indicated by a dashed arrow in FIG. 2). The cooling by the local cooling fan 3 is performed only for the integrated circuit element having particularly large power consumption, and the other cooling is performed only by the cooling fan 10.

The fan control circuit 6 mounted on the fan mounting plate 4 is used for supplying power to the local cooling fan 3 and processing a fan abnormality signal. Power for the fan is supplied from a back panel (not shown) attached to the back of the frame 9 to the fan control circuit 6 via the connector 20, then distributed, and supplied to each of the local cooling fans 3 through the cable 5. Is done. Further, a signal indicating an abnormality of the local cooling fan 3 is transmitted to the fan control circuit 6 via the cable 5 and required processing is performed. Examples of the fan abnormality signal include a signal for notifying that the fan has stopped, a signal for notifying that the rotation speed has dropped below a certain value, and a pulse signal generated in accordance with the rotation of the fan.

By using the local cooling fan 3, cooling air can be applied vertically from the vicinity of the integrated circuit element 1, so that the thermal resistance can be reduced as compared with the case where cooling is performed only by the entire cooling fan 10. In addition, by increasing or increasing the rotation speed of the overall cooling fan 10, it is not necessary to increase the wind speed, so that noise can be suppressed. Even when the local cooling fan 3 is mounted on the fan mounting plate 4 to maintain the fan, it is only necessary to pull out the fan mounting plate 4 while keeping the wiring board 2 in the rack 9. Here, if mechanical and electrical measures are taken to enable hot insertion and removal of the fan control circuit 6 and the connector 7, maintenance of the fan can be performed without turning off the power of the device.

FIG. 3 is a perspective view showing a second embodiment of the present invention, and FIG. 4 is a sectional view thereof. The difference from the first embodiment is that the wiring board 2 and the fan mounting plate 4 are mounted horizontally on the frame 9, that there is a partition 11 having an opening on the front side of the wiring board 2, Three partitions 8 of the mounting plate 4 are provided on the near side and on both the left and right sides. The opening 12 is provided on the near side partition similarly to the wiring board 2, and ducts 13 are formed on both sides of the rack. The whole cooling fan 10 is provided on the inner side of the duct 13.

In FIG. 3, air from the overall cooling fan 10 is first sucked through the opening 12 of the partition 11 of the wiring board 2 and flows around the integrated circuit element 1 on the wiring board 2 to cool it. Flows into the duct 13 from both ends, and is discharged to the back of the rack 9 by the overall cooling fan 10 (indicated by solid arrows in FIG. 3). On the other hand, in the space between the side of the fan mounting plate 4 on which the local cooling fan 3 is mounted and the wiring board 2 immediately above, the opening 1 of the front partition 8 of the fan mounting plate 4 is provided.
Air is also drawn in from the wiring board 2 and the wiring board 2 directly below the fan mounting plate 4 from the opening 7 of the fan mounting plate by the local cooling fan.
It is blown vertically onto the upper integrated circuit element 1 (indicated by the dashed arrows in FIGS. 3 and 4).

The first embodiment is suitable for the case where cooling air is flown by the entire cooling fan 10 in the vertical direction (from top to bottom or from bottom to top) of the housing of the device, whereas the second embodiment is suitable. Is suitable for suctioning air from the front of the housing and exhausting air to the rear, for example, when using a standard rack housing defined by the IEC standard.

[0019]

According to the present invention, there is a first effect that it is not necessary to increase the heat sink even when the power consumption of the integrated circuit element increases. As a result, the mounting interval of the wiring board is increased to increase the surface area of the heat sink and the thermal resistance is reduced in the device, or the interval between other components on the same wiring substrate is increased, and the wiring length between different wiring boards and components is increased. , The signal delay increases and the performance of the device does not deteriorate.

The reason for this is that since the cooling air is blown from the vicinity of the integrated circuit element by the local cooling fan, the heat transfer coefficient between the integrated circuit element and the air becomes large.

Further, the present invention has a second effect that it is not necessary to increase the wind speed by the cooling fan to reduce the thermal resistance. For this reason, the noise of the device can be suppressed low.

The reason is the same as in the case of the first effect.

The present invention has a third effect that the fan can be maintained without removing the wiring board on which the semiconductor element is mounted from the device. For this reason, maintainability is improved, and it is possible to cope with non-stop operation.

The reason is that the local cooling fan is mounted not on the wiring board but on the fan mounting plate and the fan control circuit distributes power to the fan.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the first embodiment of the present invention.

FIG. 3 is an exploded perspective view showing a second embodiment of the present invention.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

FIG. 5 is a sectional view showing a conventional cooling structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Integrated circuit element 2 Wiring board 3 Local cooling fan 4 Fan mounting plate 5 Cable 6 Fan control circuit 7 Connector 8 Partition 9 Frame 10 Overall cooling fan 11 Partition 12 Opening 13 Duct 14 Integrated circuit element 15 Wiring board 16 Frame 17 Cooling fan 18 heatsink

Claims (3)

[Claims] 1. An electronic device in which a plurality of wiring boards on which circuit elements are mounted are arranged and housed in a rack, and
An overall cooling fan attached to at least one of the lower surface and the side surface, and the plurality of wiring boards arranged and accommodated in the rack are accommodated in the rack in parallel with each other and mounted on the adjacent wiring boards. A cooling device for electronic equipment, comprising: a plurality of fan mounting plates each having an opening at a position facing the circuit element; and a local cooling fan mounted at each of the openings at the plurality of fan mounting plates. Construction. 2. The cooling structure for an electronic device according to claim 1, wherein the circuit element facing the opening is cooled by the overall cooling fan and the local cooling fan. 3. A cooling structure for an electronic device, comprising: a fan control circuit mounted on the fan mounting plate for performing power distribution to the local cooling fan and processing an abnormal signal of the fan.