US1225391A - Attachment-plug. - Google Patents

Description

E. G. K. ANDERSON.

AHACHMENT PLUG.

APPLICATION men APR.10. |913.

l 1,225,391 Patented May 8,1917.

UNITED sTATEs PATENT oEEICE.

EIRN'SL G'. IK. ANDERSON, OF CHICAGO, ILLINOIS,VA SSIGNOR T0 BENJAMIN ELECTRIC MANUFACTURING COMPANY.

ATTACHMENTPLUG.

Specication of Letters Patent.

Patented May 8, 1917.

. to the accompanying drawing, forming a part of this speciiication.

My invention pertains to attachment plugs, and especially relates to the class of plugs own as separable, .Ve., plugs consisting of two readily disengageable members,.an outer member and. an inner member, of which the outer member is adapted to be inserted into a lamp socket or the like, and the inner member carries binding terlminals for receiving the ends of leading-in conductors. It is one of the principal objects of my invention to provide a separable plug of a simple, convenient and eiiic1ent construction, in which the threaded contact of the outer member will be rotatable with respect to the remainder` thereof.

An attachment plug constructed in accordance with my invention is described,

by way of example, in the following speci cation and shown in the accompanying drawing. The construction shown and described, is, however, only one of those in which my invention may be embodied; and changes maybe made therein without exceeding the scope of my invention as defined in the appended claim:

In the drawing Figure 1 isan elevation of the plug; y

Fig. 2 is a section taken vertically through the same;

IFig'. 3 is a detached side view of the iniier contact sleeve of the outer plug mem- Fig. 4 is an inverted plan of the same;

Fig. 5 is' a vertical section through the insulating button of the inner member;

Fig. 6 is a view similar to Fig. 5, the section being taken, however, at right angles to that of Fig. 5; and

Fig. 7 is a detached inverted plan of the insulating button of the outer plug member.

Like reference characters refer to likeI parts throughout the following specification and the several figures of the aecompanying drawing.

As has been said, the plug consists of an outer member adapted to be secured into a wallsocket lamp socket or the like, and an inner member, adapted to make electrical connections with the outer member, and car rying binding terminals for receiving leading-in-wires. The outer member comprises an insulating button 10 having an axial passage formed therethrough, through which passes a rivet- 1.1, the outer end of which is iianged, at 12, to form the outer center contact of the outer plug portion. The inner end of the rivet 11 is flanged over, at 13, and serves to secure in place the Seat portion 14: of a V shaped metallic strip, the end 15 of which forms the inner.` center contact of the outer plug portion. iIhe strip 14, 15 is flexible and is reinforced by a spiral spring 16 disposed between the end 15 and the rivet 11, the button 10 being formed with a recess 17 for accommodating this spring. The button 10 is reduced at 18 to receive a metallic sleeve 19, which is secured in place thereon by means of tongues 20 which are lstamped out of the sleeve 19 and project into recesses 21 in the button. It will be seen that the sleeve 19 may be passed over the reduced portion of the button, the tongues 20 springing out to permit this. When, however, the tongues 20 have entered the recesses 21, the sleeve cannot be removed again. The sleeve 19 is formed with an out wardly extending flange 22 at its outer end, which flange engages against the shoulder -formed by reducing the portion 18 at the button.

Rotatably mounted on the sleeve 19, so as to make electrical connection therewith, is the threaded contact 23 of the outer plug portion. The threaded contact passes through, and is fianged over beyond, an insulating thumb ring 24 by means of which the contact may be manipulated in screwing the plug into or out of a socket. The sleeve 19 is formed with a Hange 25, at its inner end, which engages against the inner end of the threaded contact 23, and thus prevents the latter from being withdrawn lengthiwise, while permitting it to rotate freely with respect to the sleeve 19.

The sleeve 19 is formed with a plurality of slots 26 extending from its inner edge outward, whereby a certain resiliency, in a radial direction, 1s given. The sleeve is fur ther formed with an inwardly extending circumferential bead 27, which, when the inner plug member is in place in the outer plug member, is engaged by a corresponding circumferential groove 28 formed in a sleeve Contact 29, @which forms part-of the inner plug member. The sleeve contact 29 is formed with 'a reduced and screwthreaded collar 30fat its inner end; and it carries, at its outer end, an insulating button 3l. This button rests upon the shoulder formed by the reduced collar 30 and is retained in place by the upper edge of the sleeve contact 29, which is spun inward somewhat, to that end. The button 31 is of a substantially hemispherical shape at its upper part and enters a .correspondingly shaped cavity 32- formed inthe inner 'face of the button 1.0I of the outer plug member, so that thecenter contactofth'e inner plug member, to bedescribed below, canengage the center contact 15 of the outer plug member. A-

The button 31 of.l the inner plugmember is formed, at the center of. itsupperpartf with a cavity 33 having two holes 34 communicating therewith and with the lower end of the button... -In the cavity 33 lies abinding terminal plate 35 having lugs A36- which are bent downward to passthrough theholes 34, these lugs being bent over at their ends so as to retain the plate 35 in position. The plate 35 has a screw threaded hole through which passes a screw 37, which also passes through Vadished. center contact- 38. Communicatmg with the chamber 3 3, is a passage 39, through which a lead conductor may be brought to the plate 35 and looped around the screw `37, in which position it may be 'secured,lbeneath the center contact 38, by tightening the screw 37 The insulating button 31 is formed with acavity 39 at 'one side thereof, into which cavity the metal ofthe sleeve contact 29 is bent, so as to form a square recess 40 in the sleeve contact. The cavity 39 is larger than the bent-in portion of the sleeve contact 29, so as to provide room for the passage of the lead conductor behind the sleeve contact 29 and over the outer edge of the same. A square nut 41 is placed in the recess 40, and receives a' binding screw 42. The second lead wire is passed up into the cavity 39, behind the sleeve contact 29, and 'is bent over the latter and secured beneath the binding screw 42 (Fig. i6). It will be seen, therefore, that one of the leading-in conductors is in electrical connection with the central contact 38, while the other leading-in conductor is in electrical connection with the sleevecontact 29. l

An insulating bushing is: threaded into the collar 30, and is of such length that its edge will bind againsttherlead conductors and force them against the button 31, when the bushing is screwed home into the collar 30. By this means, a conductor grip is provided,

-translating 'device Which is connected to the which prevents the leading-in conductors from being torn away from the binding terminals during the use of the device or 111 case of a sudden pull being imparted to the reducing the collar 30 of the sleeve contact 29.

In the use of the device, the outer member is-secured into a Wall socket, lamp socket or the like, it being noted that, by reason of the 'fact that the button 10 can remain stationarywith respect to the threaded sleeve 23, the latter rotating uponthe button, the outer member will be Accidental loosenin thusj is prevented. enever it is desired to co'upleup a sadiron, electric fan', or other conductors of the inner member, this is effected by simply pushing the inner member into the outer member. When isjdone, the center contact38 of the inner member makes connection with the center contact 15 of theouter member, the latter being held in contact by reason of its own resiliency aided by'that of the spring 16. The sleeve contact 29 makes electrical -connection with the sleeve 19 of the outer member, its groove 28 engaging inthe bead 27 of the sleeve 19 and serving to secure. the inner member detachably in position. All that is necessary,

when the inner member is to .be withdrawn, is to exercise a pull upon it sufficient to overcome the spring actlon of the sleeve l19. The button 31 of the inner member, and the sleeve contact 29 are so 'shaped that the members of the plug will come apart regardless of the direction in which a pull is ap'- plied to the inner member. For instance, if' the conductors are pulled upon in a direction at an angle to the. axis of the plug, the inner member will simply be withdrawn. This is of considerable importance, in that in case of any accident, such as the falling of a sadiron or the like, by which a sudden pull is imparted to the conductors, the only result will be that the members of the plug will be separated. By this means, injury to the plug itself or to the parts of the socket, is

avolded.

In separable plugs, as hertofore provided, it was inconvenient to'secure the plugs into the socket unless the parts of the plug were separatedfirst, since, in screwing 1n the plug, the conductor wires became twisted. In the plug described above, this is not the case, the rotatable threaded contact 28 perrmly locked in the socket. v of the outer member respert to the socket, the threaded Contact lwing rotated alone to eil'ect the insertion of the plug. The plug is simple; and the parts are of such a nature that they may be made by Simple stamping and Spinning operations, wl'ufreby a strong and durable plug may be produced at a low cost.

What I claim as new and desire to secure by Letters Patent is:

.I separable attachment plug comprising two members, one of Said members including an insulating base, electrically connected inner and outer center contacts carried by said hase, a conducting sleeve secured to said basefnnd extending rearwardly thereof so as to form a chamber, and a threaded outer Contact rotatably mounted on said sleeve1 and the other member including an insulating base having a center Contact for engagement with said inner center Contact and having an outer contact for engagement with said sleeve, said members having interengaging manually releasable means for retaining them together.

In Witness whereof, I have hereunto subscribed my name in the presence of two Witnesses.

ERNST e. K. ANDERSON.

Witnesses: i

CHARLES G. COPE, T. L. ToBIAs.

Corrections in Letters Patent No. 1.225.391.

It ia hereby certified that in Letters Patent No. 1,225,391, granted Muy 8, 1917,

upon the application of Ernst. G. K. Anderson, of Chicago, Iilinois, for nn improvement` in Attachment-Plugs," errors appear in the printed specification requiring r correction ns follows: Page 2, line 35, "or tho reference-numeral 39 read 39,

emma page, line. 4l, for the recren-numeral 39 read 3.9"; and that the said Letrs Patent should be rend with these corrections therein that the acme may ccnform to tha record o! the case in the Pstent Office.

Signed and sealed this 17th day of July, A. D., i917.

F. W. H. CLAY,

[SEAL] Acting Commission# of Patna. (Il. J73-343.

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