US1739309A - Electric fuse - Google Patents

Description

Dec. 10, 1929. w. H. HUMPHREYS Er Al. 1,739,309

ELECTRIC FUSE Filed Feb. 28, 1928 'imi 3 9 70 7 l 6 70 .9 72 73 III A TTU/CNE YS Patented Dec. I, 19429 UNITED STATES PATENT oli-FICE WILLIAM H. HUMPHREYS, or YoNxEns, Ann WILLIAM J. PoLLoex, or Baonxy NEW Yom:

ELECTRIC y'isusE' Appiication filed February 28, 1928. Serial No. 257,598.

This invention relates to improvements in electric fuses, and has particular reference to a fuse of the type employed in electric circuits for the purpose of protecting the same against overloads.

An object of the invention is to provide ani' improved fuse of simple, practical and inexpensive construction wherein the fusible element employed may be easily and quickly removed and replaced.

Another object is to provide the body of the fuse with a tapered bore extending the entire length thereof and to utilize a similarly shaped plug to secure or wedge a fusible element in the bore, said plug projecting beyond the ends of the body, when the fusible element is secured in position, so that by tapping the smaller end of the plug the same may be loosened preliminary to its withdrawal from said body and subsequent removal of the fusible element.

The above and other objects will appear more clearly from the following detailed description, when taken in connection with the accompanying drawing, which illustrates a preferred embodiment of the inventive idea.

In the drawingn Figure 1 isa side elevation of the fuse constructed in accordance with the invention;

Figure 2 is an enlarged longitudinal section thereof;

- Figure 3 Figure 2;

Figure l is an end elevation; and Figure 5 is a perspective view of the fusible element.

Referring more particularly to the accompanying drawing, the numeral 6 indicates the body ofthe fuse which is made of any suitable 4o insulating material, such as 4vulcanized fibre or the like. This body is cylindrical in crosssection and is provided with a longitudinal bore 7 extending the entire length of the body and of slightly tapered formation throughis a section on Vthe line 8--3 of V out. The tapering of the bore may, however,

be dispensed with. Eachend of the body 6 has mounted thereon anelectric terminal or head 8 recessed at its end to receive the adj acent end of said body. To secure the terminals 8 to the body, the inner end of each terminal may be inturned, as indicated at 9, to extend into an annular groove 10 formed in said body. Each terminal is also provided with a central tapered opening 11 aligned with the bore in said body.

The fusible element 12 is of a standard type andwhen inserted into position in the body 6 its. ends will engage the terminals 8 so as to complete the electric circuit. The ends of the element 12 may project beyond the ends of the terminals and, in order to prevent shifting of the element in the body, when securing the former in position, the kend of said element adjacent `the larger end of the bore 7 may be bent laterally, as indicated at 13, and engaged with the terminal so as to form a stop which limits the movement of said element 12 towardthe other end of the body.

To fix the fusible element 12 in position` with its ends in contact with the terminals 8,

there is provided an insulated plug 14 tapered longitudinally throughout its length and capable of insertion into the bore of the body. i

ln so doing, the plug willwedge the element 12 in position, as shown, and cause the same to assume a cross-sectional contour conforming to those of the body and terminal members thereby securing intimate Contact therewith, it being understood that said element 12 is made of malleable metal. The plug 14 is longer than the combined lengths of the body 6 and terminals 8 so that the ends of the plug` will project beyond` said terminals when the plug is in wedging position. Thus said ends are easily accessible either for the purpose of striking the larger end thereof to increase lthe wedging action or for loosening the plug by tapping upon the smaller end. It is obvious that the latter operation can be easily and quickly accomplished in the event of the fusingof the element 12, whereupon the defective element may be extracted and a new one fixed in its place.

`What is claimed is:

1. An electric fuse including an open ended body ofinsulating material having a bore therethrough, terminal members carried by the ends of said body, a fusible element contacting-the wall of said bore and engaging said terminal members, and a tapered insulated plug extending through said bore and werliging Isaid fusible element against said wa l.

2. An electric fuse including an insulated body having a bore extending the entire length thereof, terminal membersat the ends of saidbody having openings aligned With said bore, a fusible element extending the length of said bore and having its ends engaged with said terminal' members, and an insulated plug projecting through the openings in said terminal members and said bore to secure said fusible element in engagement with said members.

3. An electric fuse .including an insulated body having a tapered'longitudinal bore extendingits entire length, end terminal membersfsecured to said body and having tapered openings aligned With said bore, a fusible element extending through said bore and having its ends engagedfwith saidterminal members, and an insulated tapered plug projecting through said openings and bore to engage said fusible element and Wedge it into intimate Contact with said terminal members, the ends of saidplugextending outwardly beyond the outer ends of said'terminal members.

4. An electric fuse including an insulated body having a bore extending therethrough, and terminal members having tapered openings-the Walls of which are aligned with and form continuation of said-bore, a fusible element extending through and contacting the Walls of said openings, and a tapered plug projecting through said bore and openings to bind said fusible element against the Walls ofthe latter.

5. An elec-trio fuse of the cartridge type including an insulated body having a tapered bore, terminalmembers at the ends of said body, a fusible element extending through theborein said body and engaged with said terminal members, and a tapered plug in said bore forl Wedging-said fusible element against the-wall thereof, the ends of said plug projecting outwardly beyond saidterminal members andbeing-exposed to permit tapping at either end when removing or Wedging in position thefusible element.

Intestimony whereof We have allixed our signatures.

WILLIAM II. HUMPHREYS. WILLIAM J. POLLOCK.

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