The present invention relates to a heat dissipation apparatus, and more particular, to a heat dissipation apparatus including two sets of fans installed within a single enclosure. Therefore, an enhanced dissipation effect is resulted because the speed and pressure generated by rotation of the fan can be adjusted according to specific requirement, while the assembly convenience is improved.
To enhance overall wind speed and pressure, two heat dissipation fans 2A and 2A′ are typically combined or stacked in series as shown in FIG. 1. Thereby, the damage of the system caused interruption of any of the fans can be avoided. However, to assemble the fans 2A and 2A′ together, fasteners such as screws have to be applied to the frames of the fans 2A and 2A′.
When the fans 2A and 2A′ are secured to each other in series, increase in wind pressure is not significant because the frames of the fans 2A and 2A′ normally include ribs 21A for reinforcing stability of the attachment. When the first fan 2A rotates to generate an air flow, the air flow is easily interrupted by the ribs 21A to cause turbulence. When the turbulence is circulating into the fan 2A′, the wind speed and pressure generated by the fan 2A′ is seriously affected. Even when the fan 2A′ remains stationary when the fan 2A rotates, the wind pressure will be lowered by the installation of the fan 2A′. The serial connection of the fans 2A and 2A′ results in significant resistance, which degrades rotation efficiency and increases the noise.