Electronic apparatus

A personal computer (electronic apparatus) (1) is equipped with a plurality of heat generating devices: a power source unit (11), a CPU (12), an FD drive device (13), a CD/DVD drive device (14), and an LCD (15), and a cooling fan (16) for cooling the plurality of heat generating devices (11) through (15). The plurality of heat generating devices (11) through (15) are arranged in parallel in a direction Y which crosses a central axis (16c) of an impeller (16b) of the cooling fan (16). Further, the heat generating devices (11) through (15) are arranged within a blowing range (21) of the cooling fan (16).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electronic apparatus, such as a computer, which has a plurality of heat generating devices.

2. Description of the Related Technology

A personal computer is generally equipped with a power source unit, a CPU (central processing unit), an FD (flexible disk) drive device, and a CD (compact disc) drive device. Some personal computers are integrally provided with an LCD (liquid crystal display).

The power source unit, the CPU, the drive devices, and the LCD generate a relatively large amount of heat. In particular, the power source unit and the CPU generate a large amount of heat. The CPU is vulnerable to heat, so that it is necessary to cool the CPU and the heat generating devices around it.

As shown inFIG. 6, in a conventional personal computer50, it is common practice to cool a CPU51by a heat sink52and, at the same time, to cool heat generating devices, such as a power source unit53, the CPU51, a CD/HDD drive device54, an FD drive device55, and an LCD56, by a plurality of cooling fans, such as a system cooling fan57a, a CPU cooling fan57b, and a power source cooling fan57c. InFIG. 6, reference numeral58indicates a main substrate, and reference numeral59indicates a casing.

SUMMARY OF THE INVENTION

However, the conventional personal computer50, in which the heat generating devices51through56are cooled by using a plurality of cooling fans57a,57b, and57c, involves a large number of devices, resulting in a rather large size.

Further, the plurality of cooling fans57a,57b, and57csend airflows in different directions, so these airflows collide with each other within the casing59of the personal computer50. As a result, the airflows are changed in direction, or reduced in pressure, so there is a fear of the heat generating devices51through56not being cooled efficiently.

In this case, it is necessary to keep the airflows from the cooling fans57a,57b, and57cin balance, which involves a bothersome control. Further, the sounds from the plurality of cooling fans57a,57b, and57care combined to thereby generate a relatively large noise.

Further, when large cooling fans are installed, the portions where such large cooling fans are installed protrude from the remaining portion of the apparatus, resulting in a rather unbalanced outward appearance.

These problems are involved not only in personal computers but also in other electronic apparatuses in which a plurality of heat generating devices are cooled by cooling fans.

The present invention has been made with a view toward solving the above problems. It is a technical object of the present invention to provide an electronic apparatus capable of cooling a plurality of heat generating devices by a single cooling fan, thereby making it possible to achieve a reduction in the number of parts, a reduction in size, and an improvement in cooling efficiency, and to suppress noise generation.

To achieve the above technical object, the present invention provides an electronic apparatus which is equipped with a plurality of heat generating devices and which is constructed as follows.

(1) The present invention provides an electronic apparatus, including: a plurality of heat generating devices; and a cooling device for cooling the plurality of heat generating devices, wherein the plurality of heat generating devices are arranged in parallel in a direction crossing a central axis of an impeller of the cooling device; and the plurality of heat generating devices are arranged within a blowing range of the cooling device.

According to the present invention, a plurality of heat generating devices are arranged in parallel in a direction crossing the central axis of the impeller of the cooling device, so the airflow from the cooling device directly hits the plurality of heat generating devices. Thus, a plurality of heat generating devices can be cooled by a single cooling device, thereby making it possible to achieve a reduction in the number of parts, an improvement in cooling efficiency, and a reduction in size, and to suppress noise generation.

(2) Example of the heat generating devices comprise a power source unit and a CPU. The power source unit and the CPU, which generate a relatively large amount of heat, can be cooled by a single cooling device.

(3) Examples of the heat generating devices further comprise an FD drive device and a CD/DVD drive device. Those drive devices can also be cooled by a single cooling device.

(4) Examples of the heat generating devices further comprise a LCD (liquid crystal display). In a computer integrated with an LCD, it is possible to cool the power source unit, the CPU, the disk drive device, and the LCD by a single cooling device.

(5) It is desirable that some of the heat generating devices are situated at right opposite a blowing port of the cooling device, the rest of the heat generating devices are situated in positions which are off the right opposite the blowing port, and no other devices interpose between the heat generating devices and the blowing port.

An airflow from the cooling device is generated by applying an axial pressure and a centrifugal force to the air through rotation of the impeller. Thus, the airflow from the cooling device is sent out over a range wider than the blowing port, so it can hit the heat generating devices situated so as not to be right opposite the blowing port of the cooling device.

(6) There can be provided as an example, the electronic apparatus, in which the power source unit and the CPU are situated at right opposite the blowing port of the cooling device, and the disk drive device and the LCD are situated in positions which are off the right opposite the blowing port.

(7) The present invention provides an electronic apparatus provided with a plurality of heat generating devices, wherein the electronic apparatus is provided with a cooling device for cooling the heat generating devices by drawing air from under the electronic apparatus; and

exhaust air from the cooling device directly hits at least one specific heat generating device.

(8) The specific heat generating device is preferably a device requiring more heat discharge than the other heat generating devices.

(9) The present invention provides an electronic apparatus casing which is capable of containing a plurality of heat generating devices, wherein the electronic apparatus casing allows attachment of a cooling device for cooling the heat generating devices by drawing air from under the electronic apparatus; and

exhaust air from the cooling device directly hits at least one specific heat generating device.

(10) The specific heat generating device is preferably a device requiring more heat discharge than the other heat generating devices.

According to the present invention, it is possible to cool a plurality of heat generating devices by a single cooling device, thereby making it possible to achieve a reduction in the number of parts, an improvement in cooling efficiency, and a reduction in size, and to suppress noise generation.

DETAILED DESCRIPTION OF THE INVENTION

In the following, an electronic apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1shows a personal computer1, which is an electronic apparatus according to this embodiment. The personal computer1is equipped with heat generating devices: a power source unit11; a CPU12; an FD (flexible disk) drive device13; a CD (compact disc) /DVD (digital video disk) drive device14; and an LCD (liquid crystal display)15; and a cooling fan16, which is a single cooling device for cooling the above heat generating devices.

InFIG. 1, reference numeral17indicates a casing, reference numeral18indicates a frame for mounting the above-mentioned heat generating devices11through15, reference numeral19indicates a heat sink for cooling the CPU12, and reference numeral20indicates a main substrate. The personal computer1is further equipped with general devices (not shown) other than those mentioned above.

The heat generating devices11through15are arranged in parallel in a direction Y crossing the central axis16cof the impeller16bof the cooling fan16. Further, the heat generating devices11through15are arranged within the blowing range21of the cooling fan16. In this embodiment, the heat generating devices are arranged in parallel substantially in the horizontal direction in the following order as from the left-hand side ofFIG. 1: the power source unit11; the CPU12; the FD drive device13and the CD/DVD drive device14; and the LCD15.

The CD/DVD drive device14is provided behind the FD drive device13as seen from the cooling fan16. On both sides of the CD/DVD drive device14, there are provided predetermined gaps d,d. The airflow from the cooling fan16passes through these gaps d,d.

The cooling fan16is provided in the lower portion of the personal computer1, and on the lower side in a direction crossing the direction Y in which the heat generating devices11through15are arranged. A blowing port16aof the cooling fan16is directed upwards.

Further, in this embodiment, the power source unit11and the CPU12are situated so as to be right opposite the blowing port16aof the cooling fan16. The FD drive device13, the CD/DVD drive device14, and the LCD15are situated so as not to be right opposite the blowing port16aof the cooling fan16.

No other device exists between the blowing port16aof the cooling fan16and the power source unit11, the CPU12, the FD drive device13, and the LCD14.

It should be noted that the FD drive device13, the CD/DVD drive device14, and the LCD15are arranged at positions where they receive the airflow from the cooling fan16.

In other words, the above-mentioned plurality of heat generating devices11through15are arranged within the blowing range21, which is obtained as follows: a blowing range22is formed by translating an opening range of the blowing port16a, which is open in the direction of the central axis16cof the impeller16bof the cooling fan16, in the direction of the central axis16c; and then, the blowing range22thus formed is expanded in directions as determined by a wind pressure F1in the direction of the central axis16cand by a wind pressure F2in an in-plane direction orthogonal to the central axis16c.

That is, as shown inFIG. 2, through the rotation of the impeller16b, the cooling fan16applies the following pressures to the air around it: the pressure F1in the direction of the central axis16c, and the pressure (centrifugal force) F2in the direction orthogonal to the central axis16c. As a result, the air from the cooling fan16is sent over the range21, which is larger than the area of the blowing port16a.

The FD drive device13, the CD/DVD drive device14, and the LCD15are arranged at positions which are off the range22that is right opposite the blowing port16aof the cooling fan16and at which they receive the airflow from the cooling fan16, that is, within the above-mentioned blowing range21.

In this embodiment, one half of the area of the blowing port16ais right opposite the power source unit11, and the other half thereof is right opposite the heat sink19and the CPU12. This arrangement is adopted because the power source unit11and the CPU12generate a large amount of heat, and require a large amount of air for cooling them.

FIG. 3is a side view of the personal computer1. The casing17of the personal computer1has a protrusion30in substantially the lower half of the rear portion thereof. A large number of exhaust holes17aare provided on either side of the protrusion30. A stand32is provided under the casing17.

Further, as shown inFIG. 4, a large number of exhaust holes17aoccupying a large area are provided in the upper surface17bof the casing17and in the upper surface30aof the protrusion30.

Further, as shown inFIG. 5, a large number of intake holes33are provided over a wide range in the bottom surface17c(the bottom surface of the protrusion30) of the casing17. Thus, air is taken in from under the personal computer1.

The above-mentioned cooling fan16is attached to the casing17. Further, a construction is adopted such that the exhaust air (airflow) from the cooling fan16directly hits at least one specific heat generating device of the above-mentioned heat generating devices.

Next, the cooling operation of the personal computer1will be described. The pressurized air (airflow or exhaust air) sent out from the blowing port16aof the cooling fan16directly impacts against the power source unit11, the HS19, the CPU12, the main substrate20, the FD drive device13, and the LCD15, and at the same time, flows around them before being discharged through the upper and side exhaust holes17a.

The airflow from the cooling fan16flows upwardly through the gaps d,d on both sides of the CD/DVD drive device14. At this time, the CD/DVD drive device14is exposed to the airflow from the cooling fan16. The air from the cooling fan16flows around the heat generating devices11through15, and is then discharged through the large number of exhaust holes17aprovided in the upper surfaces17band30aof the casing17and the protrusion30, respectively, and in the side surfaces of the protrusion30, never returning to the interior of the casing17.

As a result, the power source unit11, the CPU12, the FD drive device13, the CD/DVD drive device14, and the LCD15are reliably cooled by the airflow from the cooling fan16.

As described above, in this embodiment, the exhaust air (airflow) from the cooling fan16directly hits all the heat generating devices. It is possible to adopt a construction in which the exhaust air from the cooling fan16directly hits at least one specific heat generating device, for example, the CPU12and the power source unit11, which require more heat discharge than the other heat generating devices.

In this way, in the personal computer1of the present invention, it is possible to cool all the heat generating devices, that is, the power source unit11, the CPU12, the FD drive device13, the CD/DVD drive device14, and the LCD15, by the single cooling fan16.

Thus, there is no need to use a plurality of cooling fans as in the prior art, so that it is possible to achieve a reduction in the number of parts, a reduction in assemblyman-hours, a reduction in cost, and a reduction in size. Further, as compared with the case in which plurality of cooling fans are used, it is possible to suppress noise generation.

Further, as compared with the case in which a plurality of cooling fans are used, the possibility of failure of the cooling fan is reduced, thus achieving an improvement in terms of reliability.

Further, the cooling fan16is arranged in the lower portion of the personal computer1. Therefore, the distance between the cooling fan16and the ears of the operator of the personal computer1increases. Thus, it is possible to further suppress the noise of the cooling fan16as experienced by the operator.

Further, as described above, the cooling fan16is arranged in the lower portion of the personal computer1, so the lower portion of the personal computer1protrudes farther than the other portion thereof. However, as compared with the case in which the upper portion of the personal computer1protrudes, the oppressive sensation as experienced by the operator can be mitigated.

Further, even when the size of the cooling fan16is increased, it is possible to mitigate the oppressive sensation as experienced by the operator by providing the cooling fan16in the lower portion of the personal computer1.

Further, some heat generating devices, which, in this case, are the FD drive device13, the CD/DVD drive device14, and the LCD15, are arranged at positions which are not right opposite the blowing port16aof the cooling fan16and at which they receive the airflow from the cooling fan16, so there is no need for the cooling fan16to be so large. Thus, it is possible to reduce the cost of the cooling fan16.

As described above, in this embodiment, a large number of exhaust holes17aare provided in the upper portion of the casing17. It is desirable for the exhaust holes17ato be provided at appropriate positions which allow the air from the cooling fan16to flow efficiently toward the heat generating devices11through15and which help to prevent the air discharged to the exterior of the casing17from entering the casing17through the exhaust holes17a.

Further, at least one specific heat generating device of the above-mentioned heat generating devices, for example, the CPU12, which requires more heat discharge than the other heat generating devices, may be directly exposed to the airflow from the cooling fan16.

While in the above-described embodiment the present invention is applied to the personal computer1, the present invention is also applicable to other various types of electronic apparatus in which a plurality of heat generating devices are to be cooled by a cooling fan, for example, a workstation (a computer of higher performance than a personal computer; it is put to commercial use by a person requiring a high performance computer, such as an engineer or a designer, or is used as a network server).

The disclosures of Japanese patent application No. JP2005-294609 filed on Oct. 7, 2005 including the specification, drawings and abstract are incorporated herein by reference.