1. Field of the Invention
The present invention relates to a cartridge fuse and more specifically to a cartridge fuse provided with such a function that melted fuse ends are prevented from being shorted.
2. Description of the Prior Art
FIG. 1(A) shows an example of prior-art cartridge fuse which is disclosed in Japanese Published Examined (Kokoku) Utility Model Appli. No. 60-33578. This prior-art cartridge fuse FT is roughly composed of a fuse housing 10, a pair of female terminals 20, a fuse member (fusible conductor) 30, a spacer 40, and a housing cover 50. The fuse housing 10 is made of an insulating material such as a plastic and is formed with two insulating partitions 11, a contact holding inner wall 12, a lance engaging inner wall 13, and an inner projection 14. The female terminal 20 is formed with a contact portion 21, a lance portion 22 cut off and expanded from the contactor portion 21, and a stay portion 23. The spacer 40 is formed with an engagement groove 41. The spacer 40 is used to hold the two stay portions 23 of the female terminals 20. To subassemble the two female terminals 20, the stay portions 23 are first held by the spacer 40, and then the fuse member 30 is connected to the two top ends of the stay portions 23 of the female terminals 20.
The subassembly thus obtained is inserted into the fuse housing 10 in such a way that the contact portion 21 of the female terminal 20 is in contact with the insulating partition 11 of the housing 10; the lance portion 22 of the female terminal 20 is engaged with the lance engaging inner wall 13 of the housing 10; and the engagement groove 41 of the spacer 40 is engaged with the inner projection 14 of the housing 10. Therefore, when the subassembly is housed in the inner space of the housing 10, it is possible to stably house the two female terminals 20 within the fuse housing 10 without producing clearance between the female terminals 20 and the fuse housing 10.
In the prior-art cartridge fuse as shown in FIG. 1(A), as long as the two stay portions 23 of the female terminals 20 are connected to each other by the fuse member 30, it is possible to securely hold the female terminals 20 and the fuse member 30 within the housing 10. However, once the fuse member 30 is blown out, the two female terminals 20 become movable. Therefore, there exists a problem in that when the entire cartridge fuse is vibrated, the two female terminals 20 moves toward the center of the housing 10 by the elastic forces of the lance portions 22 and therefore both the melted fuse member ends are brought into contact with each other, thus resulting in a reconnection of the melted fuse member.