US1477643A - Fuse plug - Google Patents

Description

Dec. 18 1923. 1,477,643

J. B. GLOWACKI I FUSE `PLUG Filed July 21 1919 lllllllllfll! lilium@ Il Isl.' "l' f 225; 1 inw EDF@ HMM/c Jb/m25'. @mmc/fa Patented Dec. 18, 1923.

UNITED STATES JOHN B. GLOWACKI, OF CHICAGO, ILLINOIS.

FUSE PLUG.

Application tiled July 21.

/'o all. 'whom it may concern.:

Be it known that I, JOHN B. Gnowacxl,

a subject of the Republic of Poland, having declared my intention to become a citizen of the United States, and a resident of the city of Chicago, in 'the county of Cook and State of Illinois, have invented certain new and useful Im rovements in a Fuse Plug; and I do here y declare that the following is a full, clear, and exact description of the same, reference being had to the ac3 companying drawings, and to the numerals of reference marked thereon, which form a part of this specification.

This invention relates to screw contact fuse plugs, moreparticularly plugs adapted to screw into a fuse cutout box.

Hitherto screw contact fuse plu have been constructed so that it is di cult to insert a new fuse link after the fuse has' blown and further in many cases insufficient ventilation has beenv provided around the fuse link to ensure its action at proper times and prevent fusion thereof as the result of long continued passage of current of safe am ierage.

ne of the objects, therefore, of this inrention is to provide a simple, economical form of construction of screw contact fuse plugs in which the fuse is firmly held and yet readily replaceable when necessary.

Another ob]ect of the invention is to provide means for allowin air to pass completely around the fuse l1nk.

A further object of the invention is to provide an im roved form of fuse link.

Other and urther important objects ot this invention will be apparent from the diS- closures in the specification and drawings.

The invention (in a preferred form) is illustrated in the drawings and hereinafte more fully described.

()n the drawings Figure 1 is a side elevation of a fuse plug embodying the features of t-he present 1nvention.

Figure 2 is a section on the line 2-2 of Figure 1.

Figure 3 is a plan view of the lug. Figure 4 is a section on the ine 4--4 of igure 5 is an axial section through the fuse carrier` with parts in elevation.

Figure 6 is a section on the line` 6-6 of Figure 4, and

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1919. Serial No. 312,341.

the cup may be provided to prevent detachment of the insulation 2 from the cup 1. Centrally and detachably arranged within the cup 1, is a fuse carrier 5 comprising aI central cylindrical portion 6 of insulating material and metallic end pieces 7 and 8 screwed or cast into' each end. For, conneet-ing this carrier 5 to the cup 1 the end piece 7 may be provided with an extension 18 of reduced size adapted to fit snuglywithin a cylindrical recess 9 in the end of the cup. The outer end piece is conveniently dished at its end, as at 15, forbetter engagement with the central contact o f a socket.

A fuse 11 may be detachably secured to one side of the carrier 5 by any suitable means such as split rings 10, which clam the ends of the strip to the two metallic end pieces 7 and 8.

Preferably movement of these rings towards the center of the carrier is limited by providing longitudinal ribs 12 on the central insulating portion 6 of the carrier.

Although various forms of fuse strip may be. employed I prefer to use a strip having a series of portions 13 of reduced width as shown more particularly in Figure 2. The cross-section of theseportions 13 determines the current strength at which the fuse will blow and by vprovidin a plurality of such sections arclng is avoi ed since one or more of the intermediate parts of the fuse will fall when the sections 13 above and below it fuse, thereby producing a much wider gap than would be produced by the fusing of a single section 13.

Preferably provision is'made for allowing free circulation of air all around the parts 13 of the fuse strip and inthe form of construction shown this is accomplished by forming a series of circumferential grooves 14 in the insulating part '6 of the carrier adapted to register with the parts 13 of the fuse strip,

.The operation is as follows:

The fuse carrier 5 is detached from the plug and the rings 10 slipped off the ends. A fuse strip 11 is then laid along one side of the carrier with its parts 13 registering with the grooves 14. The rings are now slipped over the ends of the carrier to clamp the ends of the fuse link to the end pieces 7 and 8.

Next the carrier is connected to the cup 1 by thrusting the extension 18 into the recess 9 by which it is frictionally held.

rlhe plug is now ready to screw into the fuse cutout box.

ll am aware that numerous details of construction may be varied `through a wide range without departing from the principles of this invention and l therefore do not purpose limiting the patent granted further than necessitated by the prior art and the annexed claims.

ll claim as my invention 1. A fuse comprising a cylinder having metallic end portions and an intermediate portion of insulating material and split metallic rings for detachably securing a strip of fusible material along one side of the cylinder with its ends in contact with the metallic end portions, said cylinder being provided with a longitudinal ridge adapted to prevent displacement of the split metallic rings.

2. fuse plug comprising a threaded metallic shell, a cylinder arranged concentrioally within'the shell having metallic end portions and an intermediate circumferentially grooved portion of insulating material` one end portion being electrically connected germen with the shell and the other being adapted for electrical connection with a contact 1n a socket, a strip offusible material havin a portion of reduced width and split meta lic rings for securing said strip along one side of the cylinder with its ends in contact with the metallic end portions and its portion of reduced width in register with the groove in the cylinder. I

3. A fuse plug comprising a cylinder closed at one end, a cylinder of insulating material disposed therein@ a fuse carried on the outside of the second cylinder, said assembly forming an open air space between the cylinders.`

el. A fuse plug comprising a cylinder, closed at one end, another cylinder of insulating' material frictionallyvheld therein, a fuse carried on the outside of the second cylinder, said assembly forming an open ended air space between the cylinders.

5. ln a fuse plugq a. hollow cylinder of sheet metal closed at one end and open at the other, the side wall of said cylinder toward the open end being formed into a Eea

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