The invention is to provide a shell structure of three heating devices, which is mainly provided with a shell. The inner wall of the shell is fixed with an inner layer cloth. The inner layer cloth is composed of at least one plastic air tight layer cloth, one heat preservation layer cloth and one drape layer cloth in sequence, and then the three are welded and fixed by high cycle wave. Thus, the thermal efficiency of the three heating devices can be improved.本創作係在提供一種三溫暖裝置之外殼結構，主要係在該三溫暖裝置係具一外殼，該外殼內壁係固定有一內層布，該內層布至少係由一具塑性之氣密層布、一保溫層布及一披覆層布三者依序結合而成，之後再以高週波將三者熔接固定。藉此，俾提升該三溫暖裝置之熱效率。
