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Publication numberUS3539968 A
Publication typeGrant
Publication dateNov 10, 1970
Filing dateSep 24, 1968
Priority dateSep 24, 1968
Publication numberUS 3539968 A, US 3539968A, US-A-3539968, US3539968 A, US3539968A
InventorsTunstall Wilfred, Wegner Albert
Original AssigneeTunstall Wilfred, Wegner Albert
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Electrical plug blade safety cover
US 3539968 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Nov. 10, 1970 w. TUNSTALL ETAL 3,539,6$

' ELECTRICAL PLUG BLADE SAFETY COVER Filed Sept. 24, 1968 l 4 INVENTORS W/zmw ru/vsmu.

BY A4 65A? Wis/um Z/o/m M TM Aim/0e United States Patent 3,539,968 ELECTRICAL PLUG BLADE SAFETY COVER Wilfred Tunstall, 12874 2nd St., Yucaipa, Calif. 92399, and Albert Wegner, 223 Syllmer Court, Calimesa, Calif. 92320 Filed Sept. 24, 1968, Ser. No. 762,101 Int. Cl. H01r 13/44 US. Cl. 33937 1 Claim ABSTRACT OF THE DISCLOSURE Apparatus for protectively covering the blades of a conventional electrical plug and locking the covering thereto in a manner to prevent dangerous insertion by a child into a standard outlet.

One of the main objects of the invention is to provide a simple and quickly attachable locking or latching cover to the open blades of an electrical plug to prevent dangerous outlet insertion by a child.

Another object of the invention is in the provision of a safety cover for electrical plug blades that prevents outlet insertion until unlocked or unlatched therefrom.

Yet another object of the invention is to provide a metal strap for the open blades that is padlocked thereto.

The fundamental theory of the present invention is to provide a simple, easily attachable and detachable cover for the open blades of an electrical plug and locking it thereto so that a child cannot possibly be injured by attempted insertion into the conventional electrical outlet. Small children playing on the floor or otherwise are constantly endangered by attempts to insert electrical plugs which operation they have seen their elders safely accomplish. The number of accidents from this simple cause is tremendous.

Applicant has provided a simple, inexpensive and easily attachable device that absolutely prevents any possibility of child injury. The playful youngster cannot make a dangerous connection no matter what position his or her fumbling hands assume.

These and other objects and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment thereof, reference being made to the accompanying drawings, herewith wherein:

FIG. 1 is an elevational view showing the blades in safely protected position;

FIG. 2 is an enlarged perspective view of the blade attaching pin;

FIG. 3 is an enlarged perspective view of the blade safety strap; and

3,539,968 Patented Nov. 10, 1970 FIG. 4 is a view similar to FIG. 1 with certain elements shown in section.

The drawings disclose a preferred embodiment of the invention but the metal cap might well be changed and the padlock could be a powerful latching means that would require adult operation.

A conventional electrical plug 10 has the projecting open blades 12 that are normally instantly insertable in the standard outlet, not shown. It is desired to quickly and easily lock or latch a metal strap 14 over the blade tips of the plug. The strap 14 surrounds the blades 12 and has a laterally projecting arm 16. The blade overlapping sides of the strap 14 are apertured at 18 to receive a lock pin 20 having an exterior O-ring 22. A conventional padlock is looped through the ring 22 and an opening 24 in the arm 16 to provide a secure metal or otherwise strap safety cover for the blades and prevent their dangerous insertion into a conventional electrical outlet by a child in playful adult copying mood.

The operation of the device is so simple as to obviate any further explanation.

While we have described in considerable detail what we believe to be the preferred form of our invention, it will be understood by those skilled in the art that various changes may be made in the shape and arrangement of the several parts.

We claim:

1. A quick detachable safety cover for apertured blades of conventional electrical service plugs, comprising:

a protective U-shaped strap covering the open plug blades;

said strap including two arms having holes which are aligned with the apertures in said blades when said strap covers said blades;

an apertured projection extending laterally from the end of one of said arms;

a pin with an eye at one end and adapted to be extended through the holes in said arms and the apertures in said blades to unite said strap to said blades in covering relation therewith and locate said eye in alignment with the aperture in said projection; and

optionally attachable locking means extending through said eye and said projection aperture to prevent the withdrawal of said pin from said strap.

References Cited UNITED STATES PATENTS 2,545,762 3/1951 Brown 206-46 3,345,600 10/1967 Scherer 33937 3,422,389 1/1969 Husebo 33937 MARVIN A. CHAMPION, Primary Examiner I. H. MCGLYNN, Assistant Examiner

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2545762 *Aug 30, 1949Mar 20, 1951Dancyger Mfg CompanyShield for prongs of electric plugs
US3345600 *Aug 11, 1965Oct 3, 1967Scherer Lawrence FElectrical plug locking device
US3422389 *Aug 1, 1966Jan 14, 1969Husebo James LSafety plug block
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3662320 *Dec 24, 1970May 9, 1972Marx Arthur JPlug lock
US4204723 *Jan 26, 1979May 27, 1980Bloomingdale Jack WSafety plug clip
US4308730 *Mar 17, 1980Jan 5, 1982Roth Donald PElectrical plug locking device
US4407554 *Mar 16, 1981Oct 4, 1983Drall Jerry EElectrical plug safety device
US4563048 *Jan 11, 1985Jan 7, 1986Im Kwan SLocking device for an electrical plug
US4640107 *Dec 12, 1985Feb 3, 1987Slade Luman CSafety lock apparatus for an electrical plug
US5591038 *Feb 17, 1994Jan 7, 1997Panduit Corp.Plug lockout
US6935871 *May 4, 2004Aug 30, 2005Michael Maurer, Jr.Electrical cord plug lock
US20040224543 *May 4, 2004Nov 11, 2004Michael MaurerElectrical cord plug lock
U.S. Classification439/134
International ClassificationH01R13/60, H01R13/639, H01R13/00
Cooperative ClassificationH01R13/60, H01R13/6397
European ClassificationH01R13/639E