US1897323A

US1897323A - Electrical plug

Info

Publication number: US1897323A
Application number: US345625A
Authority: US
Inventors: John H Moorhouse
Original assignee: SALVATORE CONDELLO
Current assignee: SALVATORE CONDELLO
Priority date: 1929-03-09
Filing date: 1929-03-09
Publication date: 1933-02-14
Anticipated expiration: 1950-02-14

Description

. Patented Feb. 14, 1933 bodiment of the plug,

UNITED 'STATES JOHN E. IOOBHOUSE, -OF BOCH'JEBTER, NEW YORK, ASSIGNOR, BY RESINE ASSIGN-` PATENT oFFlcE EENTS, OF ONE-HALF TO SALVATORE CONDELLO, OF ROCHESTER, NEW YORK ELECTRICAL PLUG Application illed Iarch 9, 1929, Serial No. 345,625. Renewed January 27, 1932.

This invention relates to an electrical plug such as is used, for example, to connect the -cord of an electrical lamp or electric appliance of any kind to a socket supplied with electric current. The principal object of the invention is the provision of a simple and satisfactory plug which may be used either with a screw threaded socket or. with a socket of the prongreceiving type.

Another object of the invention is the provision of a satisfactory plug so constructed that it may be inserted in a threaded .socket by a straight longitudinal motion, without rotating the plug andconsequently twistin the cord to which it is attached, and whic will be firmly and satisfactorily held in the socket when it has been thus inserted.

To these and other ends the invention resides in certain im rovements and Vcombinations of parts, all) as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawing: Fig. 1 is a side elevation of a preferred emillustrating it ready for use with a threaded socket;

Fig. v2 is a side elevation showing the lug ready for use with a prong receiving soc et;

Fig. 3 is a sectional viewvtaken longitudinally through thecenterof the plug, showing the prongs twithdrawn so that the plug ma be used with a threaded socket;

. 4 is a view similar to Fig. 3 showing the prongs in position to cooperate with a uprong receiving socket;

F 1g. 5 is a transverse section substantially on the line 5--5 of Fig. 3,A showing the threaded portion of the-socket in expanded positron,

Fi 6 is a view similar to Fig. 5 showing the rea ded, portion contracted so that the plug may be inserted longitudinally in a threaded socket, and

Fi 7 is a perspective view of a closure inem r and a pair of electrical conductors.

Similar reference numerals throughout the several views indicate the same parts.

The novel provided. When the plu p ference of the socket, there being plug comprises a` body -10 of suitable Ainsulating material suchV as hard.

rubber or the like, and has 11 extending axially of the body, and opena central cavity ing into a slightly larger cavity 12 at the lower end thereo The upper end of the Vbody/has a shape .which is somewhat spiral 1n cross section, as illustratedmost clearly in Fig. 5, and around this spiral portion there is an arcuate metallic member'l which has screw threads formed thereon of the proper socket. `The threaded member is with a handle 15 near the free end o er edge thereof, and is made of metal is sujiiciently resilient so that this handle may be moved rightwardly to collapse or Provided the lowcontract the threaded member 13 toa smaller diameter, as illustrated in Fig. 6. When the diameter of the threaded member is thus contracted, it is suiiciently small so that it may be inserted in a standard threaded socket by a straight longitudinal motion, 'thout turning the plug. The dot dash cirglle 16 in Fig. 6 illustrates diagrammatically the position of a threaded socket when the contracted threaded member of the plugI is bein inserted intr.l it, and illustrates the ample c earance has been thrust longitudinally into the soc et, the contracting handle 15, is thenvreleased and the resilience of the threaded member 13 causes it to expand, resuming the arcuate shape shown proper diameter to en gage snugly with the threads of a threadedl which I 1n Fig. 5, so that it engages effectively and I' of a socket, it would come in the-socket and is prevented from wobbling in any direction.

To enable the plug to be used with a prong receivingr socket as well as with a threaded 5 socket, a slide member 2O is movably mountj to cooperate with a standard prong receiving socket, and they extend through slots .in the body- 10 of the plug, sothat when the slide member 20 is moved upwardly within the cavity 11, the prongs will be projected from the end of the plug as shown in Fig. 4. When the slide member 20 is moved downwardly to the position shown in Fig. 3, the prongs a-re then withdrawn so that their ends are substantially flush with the end of the plug, Aor even somewhat within the plug.

A closure member 25, of the shape best shown in'Fig. 7, ts within the enlargement 12 at the lower end of the plug and serves to close the cavity 11. This closure member 25 is also of insulating material, and carries two upwardly extending conducting

members

26 and 27 which lie along the sides ofthe cavity 1'1 and in contact with the

prongs

21 and 22, respectively. Thus the prongs'have a sliding electrical contact with the conducting members so that in all positions of the prongs they are electrically connected to these members. The conductors 26 andy 27 are connected at their lower ends to

wires

28 and 29 respectively which extend out through openings 30 in the closure member 25, and which lead to the lamp or appliance to which it is desired to furnish current. The closure member 25 is held in place by a pin 31 which passes through this member and through the ody 10 of the plug.

A central contact 1s provided on the plugl to cooperate with the central contact of a.

This central conby a strip of metal standard threaded socket. tact is preferably formed having a portion plug, which portion the body, so that the portion pressed sli htly by contact with the cooperating part of the socket. The strip of metal of which the portion 35 'is formed extends downwardly at 37 alongside of and in contact with they prong 21, and the extremity of this strip is bent upwardly at 38 so that it is locked to the body of the plug. The sliding contact between the strip 37 and the prono' 21 thus provides tion lbetween the central contact I35 of the plug and the prong'21 at all times, and sinc'e this prong is always electrically connected to the conductor 26'and to the wire 28, it

overlies a recess 36 in follows that the central contact 35 is always electrically connected to the wire 28.

An electrical connection between 'the other 35 at the upperend of the 35 may be de- Y left hand side of an electrical ',connec- A wire 29 and the threaded member 13 may be provided by a pin 39 passing through the wall of the plug, one end of the pin being connected to the threaded member 13 and the other end thereof being in Contact with the conductor 27, as shown in Figs. 3 and 4.

For shifting the

prongs

21 and 22 back and forth from an effective to an ineffective position and vice versa, and also for shielding the threaded member 13 when the plug is being used in connection with a prong receiving socket, there is provided a sleeve 40 arranged to slide longitudinally on" the body 10. Slots 41 are provided at diametrically opposite points in the walls of the cavity 11 of the plug, sleeve 40, the slots 41, and the slide member 20. Thus any motion imparted to the sleeve 40 in a longitudinal direction is transmitted to the slide member 20, and the

prongs

21 and 22 may easily be projected or withdrawn simply by grasping the sleeve 40 and Vmoving it longitudinally in one direction or the other. When the prongs are projected, as in Fig. 4, the sleeve member 40 surrounds the threaded portion 13 of the plug, preventing accidental contact therewith, thesleeve member being of insulating material. When the prongs are withdrawn to an ineffective position, as in Figs. 1 and 3, the sleeve 40 Vis withdrawn from the threaded member 13, so that the latter may be inserted in a vthreaded socket.

and a pin 42 passes through the A slot 43" is provided in the sleeve 40 in position to receive the handle 15. Preferably this slot is so placed that the handle 15 must be brought to the position shown in Fig. j

atively thereto to the bottom of the slot, to

the position shown in Fig. 2. When the handle 15 is then released, the resilience of the member 13 will tend to move this handle left'wardly so that it will pressagainst the the slot 43, thus frictionally engaging the sleeve 40 and holding it frictionally in its upper position. When the sleeve is shifted to its lower position to with# draw the prongs, the handle I15 normally overlies the sleeve as shown in Fig. 1, and thus locks the sleeve in this position. It is apparent that thevprongs cannot be projected to an effective position until the threaded member 13 has been contracted, and thus it is practically impossible to project the' has been disclosed, it is to be understood that l 4. n electrical plug the

wires

28 and 29 attached, my. then beinf serted in the end of the plug an the pins 31 put ifn laceto hold the parts in this position. hi e one embodiment of the invention the inventive idea/may be carried out in a number of ways. fore not to be vlimited to the precise details shown, bu t.is intended to cover all .variations and modifications thereof falling within the spiritof the invention or appendedA claims.

I clamas my invention:

1. An electrical plug comprising abody having a screw threaded portion to coo erate with a threaded socket, a prong mem er to cooperate with a prong receivingsocket, said prong member being movable from an inefective to an effective position, and a guard member` for the screwthreaded portion, said guard member bein' controlled by movement of said prong meme 21 An electrical comprising a body h 'a threaded socket, movably mounted relative arranged to be projected to tion to cooperate with socket or retracted to an ineffective position substantially within said body, and a movable shield arranged to surround said threaded. portion when said prong member is in an eiective position and to be withdrawn from said threaded portion -when said prongmem` a prong member to said body and an effective posia prong receiving termined size, 'aand an actuating member 5o mounted on said threaded portion for moving one part of said threaded portion in a generally circumferential direction relative to another part thereof to collapsesaid portion to a diameter less than theinternal diameter in said socket by asti-aight'longitudnal mo- 1on. w n

comprisin .al bod having a screw threaded g y -ate with a.' threaded socket, said. threaded portion comprising a formed in an` arc of acircle and provided with threads for cooperation with thethre'ad's of a socket,1neans forholding'one part of 5 s aid member substantially fixed, and means the scope of the r is moved to an inefective position,so thatI resilient member This applicationis therer Plug avmg a screw threade 4portion to cooperate ceiving socket, said connected to said member adjacent one end of the arc thereof for moving suchend in a circumferential direction to change the diameter of said arcuate member so that it may be inserted in said -socket by a straight longitudinal motion and may be retained therein by engagement of the threads of said thrladed portion with the .threads ofsaid soc et.

5. An electrical plug'comprising a body having a screw threaded portlon to cooperate with a threaded socket, said threaded portion being so formed that it may be 5ontracted to a diameter 'less than the diameter of the socket with which it cooperates, means for contracting said threaded portion, a prong member for cooperation with a prong/,Cre-

movable from an ineffective position to an` eii'ective position, and means interlocking said prong member with said contracting means .So that said prong member may be moved toV effective position only lwhen said threaded portion is contracted.

GnAn electrical plug comprising a body having a cavity and a screw threaded por-Kl tion to cooperate with a threaded socket, a. pair of electrical conductors within said cavity, a pair of prong members slidably mounted for movement to a `position projecting from said b`ody to cooperate with a prong receiving socket or to an ineiiective position substantially within said body, each of said prong members being in sliding contact with of a threaded-socket so that it may be inserted,

portion 4to cooperone of said electrica-l y conductors, an electrical-L connection between said screw threaded portion and one of said electrical conductors, a central contact to cooperate with a central contact .of a threaded socket, ard a sliding contactconnection" between said central contact and one of said prong members.

7. An electrical having a central cavity' and a screw threaded prong member l being plug comprising a body portion 1to cooperate with a threaded socket,

a sliding member mounted for movement within said cavity, a air of prongs mounted onsaid` sliding mem er and movable therewith, said prongs being movable to an eective position ,proj ecting from said body toco-J operate with Za. prong receiving socket and being movable to an stantially within said body, a closure member, and a "pair of electrical conductors mounted on said closure member and extending into said cavity, said"`electrical conductors `forming Velectrical 4connections for said prong members.4 Y Jol-INH. Moolnfrousia;`

ineffective positionsub-