US 1694056 A
Abstract available in
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Description (OCR text may contain errors)
Dec 4,1928. 7 1,694,056
c. CALKINS LOOKING PLUG FOR EXTENSION CORDS Filed June 16, 1927 /nven/'or Patented Dec. 4, 1928.
cnorr. OALKINS, or ALBANY, onncon.
LOOKING- ma non nxrnnsron corms.
Application flied Jane 16, 1927. Serial No. 189,834.-
' My invention relates to extension cords,
I electric connections, and similar and like devices wherein it is necessary to lock the connection when made, and to prevent the accidental breaking fof the connection when made. i p
A further object of my inventionconsists in providing simple and efiicient means'for. the locking of electric connections and more particularly those wherein an extension cord is secured to an electric light socket of the push and pull type and wherein the same may then be locked to prevent the same becoming disengaged.
A still further object of my invention consists in providing a locking plug for extension cords, as ordinarily used by mechanics and others and wherein the mechanic using the same may be'located in a position wherein it is very diilicult of access and difiicult to return from the work involved to reconnect the connection if broken and wherein the movement of the cord has a tendency to cause a disengagement of the extension cord secured to the socket.
My invention consists primarily of the Pocket. type, as ordinarily used having disorth in the appended claims, and a preferred 7 form of embodiment ofwhich is hereinafter shown with reference to the drawings which accompany and form a part of this specification. a
In the drawings:
Fig. 1 is a side elevation of one of my new and im roved locking plu for extension cords, s own in posit on within the electric circuit.
Fi 2 is a longitudinal section of the assemb ed device.
Fig. 3 is asectional end view, taken on line AB of Fig. 2, lookingin the direction indi-' cated, the same being made toshow the extension plug in locked position.
' parts throughout the several views.
Fig. 4 is aside elevation, partially-in section, of the assembled device, the same being taken on line B0" of Fig. 3.
Fig. 5 is a frlggamentary, end, sectional view, takenon line of Fig. 2, but the same being made illustrating the assembled device in unlocked position.
Fig. 6 is a side elevation of the assembled male end of the extension cord.
Like reference characters refer to like 1 is the threaded end of the extension cord, adapted to threaded engagement with the lamp socket of the electric connection and 2 is an extension cord secured to the male end 8 of the extension cord. 4 is the body portion of the threaded end of the plug having disposed therein electric connections 5 into which the extension ends 6 of the male end 3 of the extension cord is made to engage. The male end 6 of the extension cord is mserted within the engagement connection 5 and com pletes the circuit when disposed therein. An annular disk 7 is disposed against the outer end 4 ofthe body portion and'is rotatable about the central axis 8. The central axis.
8 not only serves as the center of rotation of the annular element 7, but the same passes through the collar 9, which I have here shown to be. substantially equal in outside diameter to the body portion 4, though the same may be made of a smaller diameter if found desirable and the outer end of the central axis 8 has disposed thereon a fastening element 10 disposed within the seat 11 and maintains a working relationship between the body ortion 4 and the collar 9. Two arcuate s ots 12, are disposed within the. disk 7 and each rotation of the 4 the recesses 16 are inthis position relative to the connections 5, the extension ends 6 may readily be inserted in or withdrawn from the connections 5. To permit the rotating of the disk 7 after the ends 6 have been inserted within the connections 5, each end is provided with a recess 14 to afford a clearance between the edge of the disk 7, and which admits of its rotation to the right whereby the edge portions of the disk enter the aforesaid recesses and thereby prohibit the withdrawal follow.
What Ielaim is:
1. In a device of the class described, the combination with a plu composed of two separable members, one 0 said members having rojecting extension ends and the other mem er having connections within which the aforesaid extension ends are removably 1nserted, of a diskfc'arried by the last men tioned member, said disk adapted for rotation, and means for limiting the extent of said rotation; each provided withva groove spaced from the end thereof, said disk when rotated in one direction having portions entering the aforesaid 1 grooves, and when rotated in the opposite direction having portions avoiding said grooves substantially-as described.
2. In a device of the class described, the combination with a plug composed of two separable members, one of said members having projecting extension ends, and the other member having connections within which the aforesaid extension ends are removaglv of said extension ends being,
inserted, of a disk carried by thc last mentioned member adapted for rotary movement relative thereto, said disk being provided with a plurality of arcuate slots, a stationary pinprojecting through each slot to alford means to hmitthe extent of rotation of said disk; eachof said extension ehds being provided with a groove spaced from the end 3. In a evicc of-the class described, the
combination with a plug composed of two separable members, one of saidfinendiers hav ing projecting extension ends,- and the other member having connections within which the aforesaid extension'ends are rcmovabiy inserted, of.a disk carried by the lastmentioned member adapted for rotary movement relative thereto, and means for limiting the extent of such rotation, each of said exten sion ends being provided with a groove spaced from the end thereof, said disk when rotated in one-direction having portions entering the aforesaid grooves, and the said disk being provided with two diametrically opposite recesses in the edge thereof, which when said disk is rotated in the opposite direction, oppose the recesses in the extension endsthereby admitting of the withdrawal of the extension ends from the connections substantially as described.