Cartridge fuse with two arc-quenching end plugs

• US 4,656,453 A
• Filed: 12/10/1985
• Issued: 04/07/1987
• Est. Priority Date: 12/09/1982
• Status: Expired due to Term

• Current Assignee: Littelfuse Incorporated
• Original Assignee: Littelfuse Incorporated
• Inventors: Reeder, Conrad M.
• Primary Examiner(s): Echols, Percy W.
• Application Number:
  US06/807,263
• Time in Patent Office: 483 Days
• Field of Search: 29/623, 337/202, 337/227, 337/228, 337/231, 337/233, 337/234, 337/236, 337/248, 337/252, 337/253, 337/278, 337/238
• US Class Current: 337/236
• CPC Class Codes: H01H 2085/383 with insulating stationary parts
• CPC Class Codes: H01H 69/02 Manufacture of fuses
• CPC Class Codes: H01H 85/0418 with ferrule type end contacts

Abstract

A cartridge fuse has a pair of compressed, resilient plugs in opposed ends of a passageway passing through the fuse housing. The compressed material of the plugs engages and holds the fuse filament in slight tension along the length of the passageway and provide unexpectedly superior arc-quenching qualities to prevent explosion of the fuse housing. The ends of the fuse filament can be engaged through the centers of the plugs axially to align the fuse filament in the housing or the fuse filament ends can be engaged between the plugs and the interior of the housing wall to align the fuse filament under tension diagonally in the housing.

Claims

1. An electrical cartridge fuse comprising:

a housing made of insulating material and having a fuse filament receiving passageway therethrough, said passageway being rectilinear and having opposed ends opening to the exterior of said housing;

a fuse filament longitudinally disposed within said passageway in spaced relation to the central portion of said housing and having opposed ends opening to the exterior of said housing;

a fuse filament longitudinally disposed within said passageway in spaced relation to the central portion of said housing and having opposed ends extending to the opposite ends of said passageway; and

a pair of compressible resilient solid plug members made of insulating material of an axial length at least several times the transverse dimension of the fuse filament, said plug members being secured at the opposed ends of said passageway and being resiliently laterally compressed against an axial length of the opposed ends of said fuse filament at least several times the transverse dimensions of the fuse filament captively to secure said fuse filament in said housing under a desired axial tension and wherein, upon an arc forming and burning away material of the fuse filament portion adjacent thereto, the plug members will move into the space vacated by the burned away fuse filament material to quench the arc and;

end terminals closing off the ends of said passageway and electrically connected to the ends of said fuse filament.

3. The fuse of claim 1 wherein each of said end caps has a passage extending therethrough and communicating with the adjacent end of said passageway, each end of said fuse filament passing through a respective end cap passage and being mechanically and electrically connected to the outer face of the associated end cap.

4. The electrical fuse of claims 1 or 2 wherein each of said resilient members is a solid plug that is forced fit into said fuse housing passageway.

5. The fuse of claims 1, 2 or 3 wherein said fuse housing and said passageway therein are coaxial and cylindrical, said resilient members are solid cylindrical plugs within and sealing off the opposed ends of said passageway, and said end terminal members are cylindrical members enveloping the end portions of said housing.

2. An electrical cartridge fuse comprising:

a housing made of insulating material and having a fuse filament receiving passageway therethrough, the passageway having opposed ends opening to the exterior of said housing;

a fuse filament longitudinally disposed and centered within said passageway in spaced relation to said housing and having opposed ends extending to the opposed ends of said passageway;

end terminals closing off the ends of said passageway and electrically connected to the ends of said fuse filament; and

a pair of resilient solid plug members of an axial length at least several times the transverse dimensions of the fuse filament, said members having passages therethrough with the ends of said fuse filament passing through said passages axially to align said fuse element in said passageway, said resilient members being secured in the hosuing at the opposed ends of said passageway and being resiliently, laterally compressed around an axial length of the opposed ends of said fuse filament of an axial length at least several times the transverse dimensions of the fuse filament, captively to center and secure said fuse filament in said housing under axial tension and wherein upon an arc forming and burning away material of the fuse filament portion adjacent thereto, the plug members will move into the space vacated by the burned away fuse filament material to quench the arc.