Patent ID: 8561674

Claim:
A heat pipe, comprising: a body forming an enclosed space and comprising an sidewall, a base and a cover; a wick structure disposed on an inner surface of the body, and the wick structure has an annular recess located on the base; and an inner ring disposed in the enclosed space for increasing a structure strength of the heat pipe, wherein a bottom of the inner ring is disposed on the annular recess of the wick structure, and a top of the inner ring contacts with the cover of the body and is encompassed by the wick structure located at the cover, the inner ring comprises at least one opening located close to the cover of the body for communicating inside and outside of the inner ring, the wick structure located at the sidewall of the body maintains a predetermined distance from the inner ring to define a commodious passage for being passed through by an evaporated working fluid such that the wick structure located at the sidewall of the body does not fit snug around the inner ring, the wick structure is flowed through by a liquid-phase working fluid, and the base is in contact with a heat source, such that the liquid-phase working fluid flows back to the base through the wick structure on the inner surface of the body.