1. Field of the Invention
The present invention relates to a cooling air intake structure and a desk-top computer employing the same.
2. Description of the Related Art
Computer performance, particularly of personal computers, has substantially advanced. The amount of heat generated by a processor (hereinafter central processing unit (CPU)) of a computer increases accordingly. A cooling system for quickly discharging a large amount of heat generated by the CPU out of the computer becomes important.
A heat dissipation pad, a heat sink, a heat pipe, a cooling fan, etc. are used alone or in combination to cool the computer. In high-performance computers, particularly, desk-top computers, a CPU thereof, from among components, generating the largest amount of heat is directly cooled by one of an axial fan and a flat fan. To directly cool the CPU with the axial fan, a heat sink is arranged between the axial fan and the CPU as disclosed in Japanese Unexamined Patent Application Publication No. 2001-42973.
To take in cooling air into the computer from the outside, a large number of air intake vents are opened on one of a front panel and a side panel of a housing of a computer. As shown in FIG. 8, a large number of air intake vents are opened on a front panel of the computer housing, for example.
Japanese Unexamined Patent Application Publication No. 2003-306186 discloses a computer cooling device using a cross-flow fan.
According to the disclosure, a cross-flow fan is arranged in addition to one of the axial fan and the flat fan directly cooling the CPU. The cross-flow fan outputs an air flow wide enough to be directed to a heat emission member mounted on a mother board. An air flow is directly blown on the heat emission member or on a structure surrounding the heat emission member so that heated air does not reside near the mother board. To take in external air, a large number of air intake vents are opened on the side surfaces of the computer.
Water-cooled computers have also proposed. FIG. 9 illustrates a computer 1 having a water-cooling system. As shown in FIG. 9, the computer 1 includes the water-cooling system that cools a CPU 3 mounted on a mother board 2 by circulating cooling water. In the cooling system, the CPU 3 is covered with a cooling-water jacket made of copper. Silicone grease having a high thermal conductivity is applied on a contact surface of the jacket so that heat generated by the CPU 3 is efficiently absorbed by a cooling liquid. The cooling liquid having absorbed heat is conveyed to a radiator via a reserve tank 5 and a passage frame 7 to a heat sink 9 that is projected backward from the back plane of the computer 1. Heat of the cooling liquid is discharged outside the computer 1 by a large power-supply fan 8. Cooled liquid is then circulated back to the cooling jacket 4 by a high-performance compact pump 6. The pump 6 controls the flow rate of the cooling liquid in accordance with the temperature of the CPU 3, thereby maintaining low noise level. The cooling liquid of the water-cooling system contains a glycolic anti-freeze liquid to prevent the passage frame 7 and the reserve tank 5 from corroding.