US1431940A - Refillable fuse - Google Patents

Description

S. W. FARNSWORTH.

REFILLABLE FUSE.

APPLICATION man luNEzx, 191e.

Ze/BWM Y ATroRNEY Patented Oct. 17, 1922,

UNITED STATES SIDNEY W. FARNSWORTH, OF CHICAGO,

ILLINOIS, ASSIGNOR T0 WESTING-HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION 0F PENNSYLVANIA.

REFILLABLE rusia Application nica :une 2i,

To all whom it may concern.'

Be it known that I, SIDNEY- W. FARNB- WORTH, a citizen of the United States, and a resident of Chicago, inthe county of Cook and State of Illinois, have invented a new and useful Improvement in Refillable Fuses, of which the following is a specification.

My invention relates to fuses and particularly to fuses of the rellable type.

One object of my invention is to provide a refillable fuse in which the permanent conducting parts shall be prevented from becoming coated with oxides resulting from repeated operation of the fusible elements of the saine. f

Another object of my invention is to provide a fuse that shall compriselpermanent 'members and a plurality of fusible elements severally disposed in renewable auxiliary receptacles.

A further object of my invention is to provide a fuse that shall be ruptured at a plurality of points to reducethe violence of the attendant explosion.

A still further object of my invention is to prevent burning of the insulation of refillable fuses in which re eated operation is likely to result in the ormation of relatively fi'ee paths between the arc flame and surrounding bodies.

Heretofore, refillable fuses have usually been constructed of insulating tubing, to the ends of which terminal members have been screw-threaded or otherwise attached and in which there has been free communication between the fusible elements and the terminal members or other conducting parts.

vThis construction permitted the `accumulation of oxides upon the permanent conducting members to which the fusible elements were attached, with the result that, after a relatively few operations, the added resistance of the circuit was of such value as to abnormally heat the elements and thereby cause them to be ruptured at current values much below that at which they were designed to operate. Further, the repeated passage of flame between the terminal cap threads .or other spacesv between the caps and the insulatin receptacles vey often burnedaway a su cient quantity o the insulating material to establish dangerous fire paths to surrounding bodies.

In Opracticing my invention, I so segregate 1918. Cerial No. 241,258.

a plurality of renewable fusible elements from the permanent parts of a fuse device, by enclosing the -saine in auxiliary renewa le receptacles, as to prevent the accumulation ofoxides upon the conducting parts and the burning of the insulating material thereof.

The single figure is a view, partiallyl in terminal members 4 extend, and inwardly projecting flanges 5 which have overlapping engagement with outwardly projecting flanges 6 upon the members 4 to hold the latter in position. v

A cylin rical conducting member 7, ref,- erably of copper, but which may be 0 any other suitable material, is concentrically disposed within the member 1 and extends substantially equal distances longitudinally from the center of the member 1.- Auxiliary receptacles 8 comprising discoidal end plates 9, of copper or other suitable material, and hollow cylindrical sidewalls 10, of fiber or other suitable insulating substance, are disposed between the ends of the member 7 and the inner ends of the mem-bers 4. The terminal members 4, receptacles 8 and the member 7 are placed in "rigid co-axial relation in the receptacle l by properly screwing the cap members 2 thereon. Fusible elements 11 are disposed within the auxiliary receptacles 8 andl extend between the plates 9 to which they may be secured in any suitable manner. A conducting path through the device is provided from the terminal members 4 through the plates 9, elements 11 and the member 7. Holes 12 and 13 may be provided in the plates 9 and in the parts 1 and 7, respectively, to permit `the escape of arc gases.

When a short circuit occurs, the elements 11, being in series relation and of the same cross-sectional area, are ruptured simultaneously, thereby doubling the counterelectromotive force in the circuit and reducing the explosive force caused bythe arc. A smally or gradually increasing overload may cause but one of the elements 11 to be ruptured, thus necessitating the renewal of but one of the same. inasmuch as the fusible elements are enclosed in auxiliary receptacles, that are replaced new ones after each opeiation, accumulation of oxides on the permanent conducting parts of the device and the burning of the permanent insulating parts are avoided. -In this manner, the eiliciency of the device is maintained bv reason of the fact that the fusible elements are ruptured at the current value for which they are designed, and the danger from fire to surrounding bodies is eliminated.

While I have shown and described a particular form of my invention, many changes mav he made therein without departing froin the spirit and scope thereof, as set forth in the appended claims.

I claim as my invention:

l. The combination with a unita-ry fuse structure comprising a receptacle and terminal members closing the ends thereof, of a fuse element comprising a plurality of alternately disposed unattached series-related fusible and normally non-fusible members extending between said terminal members in said receptacle, said element being rupturable at a plurality of places simultaneously.

2. The combination with a unitary fuse structure comprising a main receptacle and terminal members closing the ends thereof, of a plurality of enclosed auxiliary cartridge fuse receptacles disposed in said main receptacle and connected in circuit relation to said terminal members.

8. The combination with an enclosed fuse structure comprising an insulating receptacle and terminal members,substantially closing the ends thereof, of a conducting member disposed at an intermediate position in said receptacle, and a removable unattached fuse element disposed between each of said terminal members and said conducting member.

4. The combination with an enclosed .fuse structure comprising a hollow cylindrical insulating receptacle and main terminal members disposed at the ends thereof, of a hollow cylindrical conducting member centrally disposed in said receptacle and two renewable fuse elements each disposed between, and engaging, one end of said conducting member and lone of said terminal members, each of said renewable fuse elements comprising an insulating receptacle, auxiliary terminal members closing the ends thereof and a fusible member disposed therein and engaging said auxiliary terminal members.

5. In a fuse device, the combination with a plurality of independentcartridge fuse structures each comprising a tubular receptacle and terminal members closing the ends thereof, of means for supporting said structures in end-to-end relation to constitute a single fuse device having a plurality of fusing points.

6. In a cartridge fuse device, the combination with a main receptacle and terminal members closing the ends thereof, of a plurality of auxiliary cartridge fuse devices, each comprising a receptacle and terminal members closing the ends thereof, disposed in end-to-end relation between the terminal members of said main receptacle.

7. In a cartridge fuse device, the combination with a. main receptacle and terminal members closing the ends thereof, of a plurality of auxiliary cartridge fuse de vices, each comprising a receptacle and terminal members, disposed in spaced series relation vbetween the terminal members of said main receptacle, and means for operatively connecting said auxiliary devices.

8. The combination with a unitary fuse structure comprising a tubular receptacle and terminal members closing the ends, of a plurality of unattached fuse elements disposed within tlie receptacle and held in conluctive relation between the terminal meiners.

9. The combination with a unitary fuse structure comprising a receptacle and terminal members associated therewith, of a plurality of unattached fuse elements disposed within the receptacle and held in conductive relation by the terminal members.

l0. The combination with a unitary fuse structure comprising a receptacle and terminal members associated therewith at least one of which is adjustable, of a plurality of uiiattached fuse elements disposed within the receptacle and adapted to be clamped in 1onductive relation by the terminal meiners.

l1. The combination with a unitary fuse structure compising a receptacle and terminal members associated therewith, of a fuse element comprising a plurality of unattached fusible and normally non-fusible membersldisposed between the said terminals and thereby held in conductive relation.

In testimony whereof, I have hereunto subscribed my name this 7 day of Jan. 1920.

SIDNEY W. F ARNSWORTH.

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