PURPOSE: To make it possible to easily replace an insulated tube even when its insulating property is deteriorated due to adhesion of film-forming substance to the surface of the insulated tube by a method wherein an insulating means part is divided with a supporting stand as a boundary, the split parts are further divided with a conductive body as a boundary, and the insulating means are provided.

CONSTITUTION: Conductive members 22, which are used to connect each power source provided outside a vacuum chamber 13 and each element of the film-forming means arranged on the supporting stand 20 in the vacuum chamber 19 passing through the supporting stand 20, are insulated from the supporting stand 20 by an insulated tube 31. The insulated tube 31 is divided into an upper insulated tube 31a, an upper left insulated tube 31b and a lower insulated tube 31c, and these insulated tubes and the conductive members 22 are insulated and fixed to the supporting stand 22 using nuts 32. As the insulated tube 31 is divided into three parts, and especially, as the film- forming side, which is subjected to adhesion of vapor 5 and the like, is divided into the upper right insulated tube 31a and the upper left insulated tube 31b, the insulated tubes 31a and 31b can be replaced in the state wherein the conductive members 22 are retained without adding strength on filaments 4 and 6 which are fragible in mechanical strength and easily broken.