US2708741A - Attaching clip for two-prong electric plug - Google Patents

Description

"milf May 17, 1955 w. ORSINH 2,708,741

ATTACHING CLIP FOR TWO-PRONG ELECTRIC PLUG Filed Nov. 20, 1952 5--1 Fig@ 135.4

IN V EN TOR.

HroR/VEY United )States Patent O ATTACHING CLIP FOR TWO-PRONG ELECTRIC PLUG William Orsini, Waterbury, Conn. Application November 20, 1952, Serial No. 321,550 1 Claim. (Cl. 339-276) This invention relates to electric plugs commonly used for connecting a power source with an electric appliance, and more particularly to a strain relieving clip for attaching a cable wire to a terminal of such a plug.

Many such devices have been proposed in the past, but involved complex and complicated constructions, requiring the use of an excessive amount of cord and metal.

One object of the present invention is to provide a device of `the above nature, having novel means for relieving the strain of the connection between'lthe appliance cord and the plug.

A further object is to provide a device of the above nature which will be simple in construction, inexpensive to manufacture, easy to install and manipulate, compact,

ornamental in appearance, and very efficient and durable in use.

With these and other objects in view, there has been,

illustrated on the accompanying drawing, one form in which tlie invention may conveniently be embodied in practice.'

In the drawing,

Fig. lrepresents a top plan view of a strain relief clip embodying the invention showing the offset staggered prongs bent up into a vertical position.

Fig. 2 is an end view of the same.

Fig. 3 is a side view of the same.`

Fig. 4 is a plan view of the clip similar to Fig. l, be fore the prongs have been bent up.

Fig. 5 is a plan view of a blank strip of metal from which the clips are being stamped in interfitting relation to produce the minimum of scrap.

Fig. 6 is an end View of a two-prong plug having two of the strain relief clips assembled therein according to the first method of assembly. v

Fig. 7 is a view, similar to Fig. 6, in which one of the conductors has been loosely embraced by the ears of one strain relief clip, and the other conductor has been clamped by the ears of the other clip.

Fig. 8 is an end view of a strain relief clip, and a stranded conductor wire loosely embraced thereby.

Fig. 9 is an end View of the clip after the ears have been tightly clamped upon the conductor wire.

Fig. l0 is a plan view of the portion of a two-conductor cable with two strain relief clips soldered upon the bared stranded ends of the insulated conductors, according to the second and preferred method of attaching said clips.

Referring now to the drawing, in which like reference numerals denote corresponding parts throughout the several views, the numeral 10 indicates a hollow two-prong plug having a pair of prongs 10a, 10b projecting therefrom, said prongs having perpendicular bases 10c located on the inside of the hollow cap, within the cavity 11 thereof.

The numeral 12 indicates a rear aperture in the cap 10 through which the insulated conductors 13 and 14 of the cable 14a are passed.

The numerals 15 and 16 indicate the bared stranded wlre ends of the cable conductors 13, 14 which are shown in Fig. 6 prior to being attached to the bases 10c of the prongs 10a and 10b.

As clearly shown in Fig. 5, the attachment strain relief clips 18 of this invention are adapted to be stamped out of a blankvstrip of metal 17 in succession as in a punch press, in such a manner that the successive stampings are intertted with one another to produce the minimum amount of scrap 27.

The clips 18 are provided with curved ends 19, which embrace inclined open slots 20. The other ends of said clips 18 are provided with oliset ears 21, 22 and open recesses 23, 24 on opposite sides of said clips.

As clearly shown in Figs. 8 and 9, the ears 21 and 22 are adapted to be first bent up and then forced down into clamping engagement with the bared stranded wire terminals 15 and 16 into the shape shown in Fig. 9.

If desired, the clips 18 may first be attached to the bases 10cof the prongs 10a and 10b, and then locked in position by inserting the headed screws 26.

According to the preferred method of assembly, however, the vclips 18 will be permanently attached to the stranded wire ends l5, 16, by bending the ears 21, 22 into engagement with said wire and then securing them thereto by means of solder 25, as clearly Vshown in Fig. 10.

One advantage of the present invention is that the scrap pieces 27 which are located only on one side of the strip 17, are quite small thereby lowering the cost of manufacture of the strain relief clip considerably.

Operation In operation, each strain-relieving clip may be attached to the prongs 10a and 10b of the plug 10 by fitting the slot 20 on said clip around the shank Vof the headed binding screw 26, which may then be tightened by means of a screw driver or other tool.

The stranded wires 15, 16 of the cable may then be inserted through the rear aperture 12 and placed between the upstanding ears 21, 22 of the clips 18, which ears will then be bent downwardly around said wires so that the cord cannot be pulled out.

It will also be understood that when the alternative method of attaching the clips to the plug is employed, the yclips will be first attached and soldered to the stranded wire ends 15 and 16 and then inserted through the aperture in the plug, after which the headed binding screws 26 will be tightened to clamp the clips in position within the plug 10.

While there has been disclosed in this specification, one form in which the invention may be embodied, it is to be understood that this form is shown for the purpose of illustration only and that the invention is notto be limited to the specific disclosures, but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all modifications and embodiments coming within the scope of the following claim.

Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent is:

ln a strain relief metallic clip for detachably connecting the end of a bare conductor wire to the base terminal Patented MayA 17, 1955 of a two-prong electric plug, a strip metal member curved ai: one end and provided with an inclined inwardly-extending parallel edged slot on one side to embrace the shank of one of the binding screws of said plug, the other end of said member being provided with a pair of oppositely extending longitudinal ears oset from each other, said member having a pointed prong spaced from the ear on said slotted end defining a rectangular recess which is adapted to intert with the ear on the other end of Said member so as tofpermi-'t' production of a plurality of: said clips by stamping them successively from coiled strip with the minimum of scrap.

References Cited in the file of this patent UNITED STATES PATENTS Wheeler Aug. 30, 1887 McIntire Feb. 25, 1890 Schneider June 28, 1910 Heineman Aug. 6, 1918 Conradi et al. July 2, 1940 Parker July 7, 1942

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