US1497323A - Renewable fuse - Google Patents

Description

' Jung 16, 1924.

. 1,497,323 H. E. BUTLER RENEWABLE FUSE Filed Jan. 19, 1923 ihventnr Henry E, Butler;

Patented June 10, 1924.

UNITED STATES PATENT OFFICE.

HENRY BUTLER, OF SCHENECTADY, NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

RENEWABLE FUSE.

Application filed January 19, 1923.

T all whom it may concern:

Be it known that I, HENRY E. BUTLER, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in Renewable Fuses, of whichthe following is a specification.

My present invention relates to renewable plug fuses suchas are used in household lighting-circuits and has for its object to provide an improved renewable fuse which is simple in structure, permits of a large number of renewals and can be manufactured at a low cost; also one in which the fuse wire or ribbon can be quickly and easily changed. 7

For a consideration of what I believe to be novel and my invention, attention is directed to the accompanying specification and the claims appended thereto.

In the drawing, Fig. 1 is a perspective View of a fuse plug embodying my invention; Fig. 2 is a sectional view thereof; Fig. 3 is a perspective view of the base of the fuse plug; Fig. 4 is a perspective view of the fuse carrier; Fig. 5 is a perspective view of the cap of the fuse plug, and Fig. 6 is a perspective View of the fuse carrier showing the fuse wire or ribbon in another position.

Referring to the drawing, the base of the fuse plug comprises a block 10 of insulating material provided on its outer surface with a metal shell 11 in the form of screw threads adapting the base to screw intola standard fuse receptacle. Block 10 is provided with a central-chamber 12 in which is located post 13. Extending through post 13 ,is a

conductor 14 which electrically connects an outside contact 15 with an inside contact16, the latter being located on the end of post 13. Shell 11 and contact 15 form the usual fuse plug terminals which are connected by the fuse wire or ribbon. The outer end of block 10 is enlarged somewhat as indicated at 17 and is threaded on its outer surface to receive a cap 18 provided with a window in the form of an opening 19 covered by a piece of suitable transparent material 20 such as is ordinarily used in fuse plugs. In the inner surface of the enlarged outer end of block 10 is a recess 21 in which is located a spring contact 22 electrically connected to shell 11. It may be formed as a extending parallel thereto.

Serial No, 613,564.

separate piece soldered or otherwise c011- nected to shell 11 or it may be formed as an integral part of shell 11. Formed in block 10 adjacent to itsouter end is an annular shoulder 23.

The fuse wire carrier comprises a block 24 ofinsulating material with a flange 25 at its outer end which seats on the outer end of block 10 and a shoulder 26 which engages. shoulder 23 in block 10. The inner end of block 24 fits recess 12 in block 10 and is provided with a recess 27 which receives post 13. Preferably post 13 and recess 27 are maderectangular so the fuse carrier cannot be twisted relatively to the base. In the outer end of block 24: is a cavity 28 and directly beneath flange 25 is an opening 28 which communicates with cavity 28. Cavity 28 is adapted to receive a roll or package of fuse material 29 one end of which extends through opening 28*, thence along the outer surface of block 2%. and into recess 27 where it is held by post 13 in engagement with contact 16. At the side of block 2% spring contact 22 engages the fuse material as shown in Fig. 2, the fuse material thus connecting contact 15 [to shell 11. On th inner end of block 24 is a guard or holder 30 in the form of a pin fastened at one end to the block and Cap 18 serves to hold the fuse plug assembled.

hen a fuse plug as shown in Figs. 1 and 2blows out the fuse material will open between contact 16 and spring c0ntact 22 and may be inunediately renewed as follows:First, cap 18 is unscrewed and the fuse carrier removed from the base. The

end of the fuse material will be projecting from cavity 28 and by pulling on it a new length of fuse material will be pulled off roll 29, enough being pulled out to reach along the side of the carrier and over its inner end as shown in Fig. 4c. The end of the material is passed under guard or holder 30 to hold the material in place. The fuse carrier is then replaced or pushed in the base and cap 18 screwed back into place to hold the plug assembled. When the fuse carrier is replaced in the base, post 13 strikes the fuse material, forces it down into recess 27 after the manner shown in Fig. 6 and holds it there. The fuse car rier is replaced in the base in such manner that the fuse material will come into engagement-with spring contact 22 aud'if desired suitable means may be provided to insure the correct insertion. In the present instance this is accomplished by providing a projection 31 on the carrier which fits into a groove 32 in the wall of the base.

The fuse material may be of any suitable shape but preferably I employ material in the form of a ribbon of suitable thickness and width to give it a cross sectional area such that it will burn out under the desired conditions. The roll of fuse material may be of any suitable sizeto give a desired number ofrenewals, it being only necessary that up a new roll can be substituted. The current passes through the portion of the fuse material located between contacts 16 and 22, the 'roll itself'being outside the circuit. This is an important consideration as it insures that when the fuse burns out the roll 'will be in no way affected or damaged. It is desirable that the fuse burn out at a point as remote as possible from theroll of fuse material so as to afford the roll the "greatest degree of protection and to insure this I preferably provide the fuse material a spaced points with sections of diminished cross sectionalarea as indicated at 33, the arrangement being such that a section 33 occurs at about the inner end of the fuse car-- rier when the parts of the fuse plug are assembled. This means then that the fuse will blowout in the lower end of chamber 12 beyond the inner end of the fuse carrier and that the effects of the blow out will be confined primarily to this portion of chamber 12. In any event, the roll of fuse material cannot be injured'by a burning out of the fuse: Also. this arrangement protects the inner contact 16' from being injured by bur ing when the fuse blows.

In renewing the fuse, when cap 18 is screwed down the fuse carrier is wedged tightly into the base block bringing the fuse materialin firm electrical contact with contacts 16 and 22. Preferably-the telescoping parts are tapered slightly as shown so as to insure a firm engagement between adjacent surfaces, V r

From a consideration of the foregoing, it will be seen that my improved fuse plug is simple in structure, can be manufactured. at

a low cost and the fuse can be quickly and it fit in cavity 28,'and when one roll is used V a base having a chamber therein, spaced coneasily renewed. Also that the fuse plug can be used indefinitely-by providing additional rolls of fuse material.

In'accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have itunderstood that the apparatus shown is only illustrative and that the invention'inay be carried out by other IDQFLDS.

What I claim as new and desire to secure by Letters Patent of the United States,' 1s 1.111 a renewable fuse, the combination of tacts in the chamber, a fuse carrier the inner end of which enters said chamber, a'package of fuse material'carried by the outer end of of which fits said chamber in the base, the

outer. end of. said carrier being provided with a cavity, a package of fuse material in said cavity, an end, ofsaid fuse material extending along the side of the carrier and overthe inner end thereof, and being in engagement with said contacts, and releasable means for maintaining the fusecarrier in posltion on the base.

3. in a renewable fuse, a base having a chamber therein, a central post in the-cham- Y her, a contact on the end of the post, a second contact in spaced relation to the firstnamed contact, a fuse carrier which fits into said chamber and has a recess to receive said post and a cavity 1n ts outer end, a continuous piece of fuse materlal located in said cavity andhaving an end extending along the side ofcthe carrier and into said recess and being n engagementiwlth SfllCl contacts,

and means for holding theba'se and carrier.

: .in. assembled position:

In witness :whereof, .I have hereunto set my hand this 10th dayof January, 1923.

, HENRY E. TLER.

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