Patent ID: 8593805

Claim:
A thermal module comprising: a circuit board defining a through hole; a centrifugal fan comprising a casing and an impeller received in the casing, wherein the impeller is smaller than the through hole, and extends through to be located in the through hole, the casing comprising: a top plate located above the circuit board and aligned with the through hole, and the top plate defining a first air inlet aligned with the through hole of the circuit board; a first sidewall extending from a circumferential edge of the top plate toward the circuit board and abutting a top surface of the circuit board around the through hole; a bottom plate located below the circuit board and aligned with the through hole, the bottom plate defining a second air inlet aligned with the through hole of the circuit board, and the second air inlet equaling the first air inlet in size; and a second sidewall extending from a circumferential edge of the bottom plate toward the circuit board and abutting a bottom surface of the circuit board around the through hole; and a fin assembly located adjacent to the centrifugal fan, the centrifugal fan generating airflow to the fin assembly, the first sidewall of the centrifugal fan defining a first air outlet oriented toward and matching an upper portion of the fin assembly, the second sidewall of the centrifugal fan defining a second air outlet oriented toward and matching a lower portion of the fin assembly, and a total size of the first air outlet and the second air outlet being the same as a size of the fin assembly.