Abstract: A heat pipe includes a casing, a main wick structure received in the casing and attached to an inner surface of the casing, a multi-layered auxiliary wick structure received in the main wick structure and a working fluid contained in the casing and saturating the main wick structure and the auxiliary wick structure. An inner peripheral surface of the main wick structure and an outer peripheral surface of the auxiliary wick structure cooperatively define a vapor channel therebetween. The auxiliary wick structure extends along a longitudinal direction of the casing and defines a liquid channel therein. The auxiliary wick structure is formed by a plurality of layers radially stacked on each other, such that each outer layer is attached around an adjacent inner layer.

Abstract: A heat pipe includes a longitudinal casing, a main wick structure, at least one auxiliary wick structure and a working fluid contained in the casing and saturating the main wick structure and the at least one auxiliary wick structure. The main wick structure is received in the casing and attached to an inner surface of the casing. The at least one auxiliary wick structure is received in the main wick structure. An inner peripheral surface of the main wick structure and an outer peripheral surface of the at least one auxiliary wick structure cooperatively define a vapor channel therebetween. At least one end of the at least one auxiliary wick structure is fixed on a corresponding end of the casing.