HEAT DISSIPATION DEVICE AND ELECTRONIC DEVICE USING THE SAME

A heat dissipation device includes a heat sink, a centrifugal fan, and a fixing member. The centrifugal fan is enclosed and attached to a heat sink by a fixing member. Air sucked into the centrifugal fan takes away from the heat sink the accumulated heat from an electrical component of an electronic device.

FIELD

The subject matter herein generally relates to heat dissipation devices.

BACKGROUND

In general, air pressure generated by a combination of an axial flow fan and a cooling ventilation is very weak, and such arrangement takes up a large space in a computer case.

DETAILED DESCRIPTION

The electronic device400in an exemplary embodiment comprises a heat dissipation device100and an electrical component200. The heat dissipation device100is configured to dissipate heat generated by the electrical component200. In at least one embodiment, the electronic device400can be a computer.

FIG. 2illustrates that the heat dissipation device100comprises a centrifugal fan10and a heat sink20.

The heat sink20comprises a cylindrical thermal conductor21and a fins group23, in a circular overall shape. The fins group23comprises a plurality of fins. The fins group23extends around the cylindrical thermal conductor21.

Four mounting suites25are defined in the fins group23. The four mounting suites25are distributed at the four corners of a rectangle.

Each mounting suite25comprises a mounting sleeve252and a mounting groove254. Four mounting sleeves252and four mounting grooves254are extended from the fins group23along a horizontal direction.

FIGS. 3-5illustrate that the centrifugal fan10comprises an upper cover12, a bottom cover14, and a fan impeller (not shown in figures). The upper cover12and the bottom cover14together forms an enclosed space, and the fan impeller occupies the enclosed space.

A suction outlet16is defined in the bottom cover14for drawing in local air (that is to say, air within the electronic device400) into the enclosed space when the fan impeller is energized. An exhaust outlet18is defined in the enclosed space to discharge air sucked from the suction outlet16.

The bottom cover14has three flanges142extending horizontally outward, and the three flanges142correspond to the positions of any three mounting sleeves252of the heat sink20.

A fixing member30is aligned with the flange142, and the fixing member30is perpendicularly mounted to the flange142. The fixing member30extends through the flange142and is engaged in the mounting sleeves252of the bottom cover14, to fix the centrifugal fan10with the heat sink20. In at least one embodiment, the fixing member30can be a screw.

FIG. 6illustrates that a gap40is formed between a first surface42in which the bottom cover14is located and a second surface44where a top of the fins group23is located, to increase the air intake area.

The reduced air pressure leads to a corresponding increase in air flow rate between the centrifugal fan10and the heat sink20, and the heat removal efficiency can be improved.

When it is desired to mount the heat dissipation device100in the electronic device400, it is only necessary that four positioning parts50respectively extend through four mounting grooves254to engage in four mounting holes of a circuit board on which the electrical component200is located. At this time, the cylindrical thermal conductor21of the heat sink20will be directed to one electrical component200, and the heat generated by the electrical component200is conducted to the cylindrical thermal conductor21.

For example, when the electrical component200is a central processing unit (CPU), the cylindrical thermal conductor21of the heat sink20is directed to the CPU, and the cylindrical thermal conductor21takes heat from the CPU. Due to rotation of the centrifugal fan10, air pressure increases an amount of air drawn in by the suction outlet16of the centrifugal fan10, and heat can be simultaneously removed from other heating elements (such as a hard disk) in the electronic device400.

In operation, the components of the electronic device400give off heat. The heat generated by the electrical components200or one of them is conducted to the fins group23through the cylindrical thermal conductor21. At this time, the centrifugal fan10generates enough reduction in air pressure to suck cold air in the system from the suction outlet16. The centrifugal fan10removes heat from other heating elements in the electronic device400, and hot air is discharged through the exhaust outlet18. Thus, the cooling air sucked by the centrifugal fan10dissipates heat from the fins group23, thereby lowering the temperatures of the plurality of electrical component200.