Purpose: To provide a center seal device which is used for a positive type pillow packaging machine and seals a portion where both side edges of a packaging film formed in a cylindrical shape and protruding downward of a conveying surface are overlapped. A center sealer 23 c which is arranged below the pair of upper plates and holds and heats both side edge parts protruding downward from a gap between the pair of upper plates; and an upper plate unit 40 to which the pair of upper plates are attached, And a support part 50 which supports the packaging machine so as to be pulled out to the front side of the packaging machine. The figure is in a fully pulled state to this side, from which the top plate unit can be turned down and supported in a suspended state. Fig. 13
