| 摘要 |
<p>A heat seal bar (19) is provided which is free of cutting of a heating ribbon (35) during repeated sealing. The heat seal bar (19) comprises a bar body (31) in the form of an elongated block, an insulating layer (33) which covers the surface of the bar body (31), and a heating ribbon (35) fixed to the surface of the insulating layer (33). A heat pipe (41) is embedded in the bar body (31) to extend along the heating ribbon (35), and maintains the entire heat seal bar (19) uniform in temperature by transferring heat from a portion of a smaller heat load to a portion of a larger heat load in a longitudinal direction of the heat seal bar (19). Accordingly, both end portions and the central portion of the heating ribbon (35) are brought into a steady state in a region of the same temperature as those of the remaining portions, so that the heating ribbon (35) expands uniformly over its entire area to eliminate the generation of such phenomenon that expansion is different between the heating ribbon (35) and the insulating layer (33).</p> |
