THERMOSENSITIVE PELLET TYPE THERMAL FUSE

摘要

PROBLEM TO BE SOLVED: To provide a thermosensitive pellet type thermal fuse that prevents members from being fused and bonded with each other due to ark generated from a contact part without increasing the number of parts.SOLUTION: A thermosensitive pellet type thermal fuse comprises: a hollow metal case 18; a second lead 19 laid at one end of the metal case; an insulation pipe 12 for closing an opening end of the metal case; a thermosensitive pellet 15 which includes a first lead 11 passing through the insulation pipe and defining its inner end as a contact point, and which is laid in contact with the second lead; and a movable contact point 17 which makes contact with the inner end of the first lead via the thermosensitive pellet and is always biased to an opening direction. The thermosensitive pellet type thermal fuse limits an exposed area of the inner end of the first lead by encompassing the inner end peripheral border of the first lead with a peripheral wall 16 formed on the insulation pipe and by narrowing a gap L1 between the insulation pipe and the movable contact point, and shields metal parts such as a compression spring 13 placed outside the peripheral wall from arc discharge generated when the movable contact point making contact with the contact point of the first lead and the contact point of the first lead are separated.