Electrical inductive apparatus with removable protective fuse

Claim 1

Electrical inductive apparatus, comprising: a casing having electrical bushings, and an opening, liquid dielectric means disposed in said casing, electrical winding means disposed in said casing and immersed in said liquid dielectric means, protective fuse apparatus, including a tubular receptacle and a removable fused portion, said receptacle having first and second ends, an opening extending between its ends, and a metallic cap member disposed to seal the opening at the second end of the receptacle, means sealingly mounting the receptacle through the opening in said casing, with the first end of the receptacle being accessible outside said casing, and with its second end extending into said casing, said receptacle including first, second and third axially aligned tubular members, providing first, second and third inner surfaces, respectively, with at least the second and third tubular members being immersed in said liquid dielectric means, said second tubular member being metallic, having a substantially smooth, curved outer surface, said first and second tubular members being formed of electrical insulating materials, said first and third tubular members extending for predetermined dimensions into opposite ends of said second tubular member, providing first and second joints between said second tubular member and said first and third members, respectively, which are shielded by the outer surface of said second tubular member, means sealing said first and second joints, preventing entry of said liquid dielectric means into the opening of said receptacle, said removable fuse portion including fuse means having first and second electrodes, handle means for removably inserting said fuse means into the first end of the opening in said receptacle, and first and second contact members connected to said first and second electrodes, respectively, said first and second contact members being adapted to make sliding contact with the inner surface of said second tubular member, and to engage the contact member connected to said metallic cap member, respectively, when said removable fuse portion is in assembled relation with said receptacle, first and second arc extinguishing members carried by said receptacle and removable fused portion, respectively, which are disposed to confine and extinguish an arc formed between the second contacts of said removable fused portion and the contacts of said metallic cap member, first and second terminals connected to said second tubular member and to said metallic cap member, respectively, and means electrically connecting said first and second terminals between said winding means and a bushing on said casing.