|Publication number||US3416123 A|
|Publication date||Dec 10, 1968|
|Filing date||Feb 28, 1966|
|Priority date||Feb 28, 1966|
|Publication number||US 3416123 A, US 3416123A, US-A-3416123, US3416123 A, US3416123A|
|Inventors||James L Husebo|
|Original Assignee||James L. Husebo|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (16), Classifications (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
.1. L.. HusEBb 3,416,123
Dec. 10, 1968 PLUG BLOCK Filed Feb. 28. 19 66 FIG. 3.
FIG-4 INVENTOR' JAMES 1., HUSEBO BY 6 4 United States Patent 3,416,123 PLUG BLOCK James L. Husebo, 5132 Evans St., Omaha, Nebr.
Filed Feb. 28, 1966, Ser. No. 530,443 4 Claims. (Cl. 339-37) ABSTRACT OF THE DISCLOSURE tainer from its prong-retaining position, the body having I a hasp opening therethrough, a padlock having its hasp extending through said hasp opening, the position of said hasp opening being such that said hasp opening and said padlock form parts of said releasable preventing means.
Comparison with the prior art Plug blocks have been proposed in the prior art in years past and the reason why they have not been of greater popularity has, in my opinion, been because of their great cost.
One way to eliminate some of the cost to a consumer has been the use of a common padlock, as was proposed in the patent to G. H. Darrell, issued July 22, 1958, Patent No. 2,844,805, and titled Plug Locking and Protecting Device. A serious disadvantage with the Darrell construction was, in my opinion, the impossibility of supporting the Darrell prong opening engaging pins from both sides of the prong, as is a feature of my invention.
The reason that a prong retaining pin must be supported from both sides of a prong is because such a pin is inherently weak, both from size and because of the material from which it is constructed.
The size of a retaining pin is tiny. This is necessary in order that it be readily and easily receivable through the small openings that extend trhough plug prongs. Economy is achieved when the thin long retainer is formed of the same material as that part of the assembly which is attached to the retainer but is disposed outside of the body of the plug. 7
It is, therefore, an object of my invention to provide my concept of having a retainer pin extend completely through both of the prongs and with the retainer pin supported by the walls of a retainer pin opening at that part of the pin which receives great breaking stress, namely, that part that is disposed between the plug prongs.
Another object is to provide a retaining pin as described with support from the retaining opening walls at the innermost tip of the pin where breakage forces are also great.
Still another object is to provide a plug block the retaining pin and body portions of which need not be connected during manufacture, as is the case with the Darrell device as represented by a pivot pin 21 therein, whereby economy of manufacture is achieved by avoiding a manual assembly operation.
A further object is to provide a retainer pin as described with means on its outer end and movable therewith which can be readily gripped by the fingers of an operator for facilitating the removal of the pin and serving the double purpose of acting also as a part of means for releasably preventing the removal of the retainer, another part of the latter means being a padlock itself.
The following drawings show only one example of a way in which the principles of the plug block of this inice vention can be used and it is understood that these principles can be used in a product considerably changed from the example shown, all within the spirit of the invention as hereinafter claimed.
In the drawings:
FIGURE 1 is a top plan view of an electrical plug block of this invention shown as applied to two of the prongs of a three-pronged plug, the latter being shown in dotted lines.
FIGURE 2 is a sectional view taken along the line 22 of FIGURE 1.
FIGURE 3 is a sectional view taken along the line 3-3 of FIGURE 2.
FIGURE 4 is a sectional view taken along the line 4-4 of FIGURE 2.
The plug block of this invention is generally indicated at 10 in FIGURE 1 and has a body 12 having a first prong recess 20 in a forward side 30 of the body, the recess 20 being of a size for receiving the apertured prong 34 of the plug of an electrical cord 42, as seen in dotted lines.
The first prong recess 20 is elongated in depth having side walls 24 presenting a elfective prong-receiving space 44, which latter, as viewed from the outside of the prong recess 20, looks substantially like the recess 20 appears in Figure 4 since it happens to be of a uniform crosssection throughout the majority of its length.
The prong-receiving space 44, as viewed from the outside of the prong recess 20, is defined by those portions of the prong recess 20 which are in alignment with the outermost end 56 of the recess 20 whereby the space 44 defines substantially that area of the recess 20 which can be actually occupied by a straight prong.
The body 12 has a retainer opening 60 extending through another side 62 of the body 12, the said other side preferably being the top side as seen in FIGURE 2 and the retainer opening 60 being in alignment with the prong recess 20 as viewed in any vertical cross-section extending through the recess 20, such as the cross-section shown in FIGURE 2.
The retainer opening 60 extends transversely to the prong recess 20 and preferably at a right angle or normally thereto.
An elongated retainer is disposed in the retainer opening 60 and extends into the prong recess 20 beyond that portion of the prong space 44, above defined, which is fartherest from the entrance 78 of the retainer opening, whereby when the retainer 70 extends through the prong opening 84 of the prong 34, the retainer 70 will retain the prong 34 in the block 12.
Releasable preventing means is provided for preventing the removal of the retainer 70 from its prongretaining position.
Such preventing means can have many forms, an example of one form is shown in FIGURE 2 in which the preventing means 90 involves providing the retainer with a head 98 embedded in a prong retainer holder 100 to which the outer end of the prong retainer 70 is attached.
The prong holder 100 preferably has a dog opening extending vertically therethrough in approximate parallelism with the elongated retainer 70.
The body 12 has a dog projecting therefrom and attached thereto in a position for extending through and beyond the dog opening 120 at times when the retainer 70 is in its prong retaining position.
The dog 140 has an outer portion 146 provided with a hasp aperture therethrough for receiving the hasp of a padlock 174, the hasp aperture 160 being disposed suificiently close to the retainer receiving holder 100 so as to cause the padlock 'hasp 170 in the hasp aperture 160 to prevent the retainer holder 100 from moving away from the body 12 sufficiently to move the retainer 70 out of retaining position with respect to the prong opening 20.
As would be best seen in FIGURE 2, the releasable preventing means 90 comprises a lock means 174 and the releasable preventing means 90 is so constructed that when the lock means 174 is unlocked and moved to a release position, and the retainer opening is disposed with its entrance downward, and with the wall surfaces of any prong aperture 20 not binding excessively against the prong means 34 received therein, then the retainer 70 will fall out of its retainer opening for convenient removal therefrom.
As best seen in FIGURE 2 and also in FIGURE 4, the retainer opening 60 has an enlarged entrance 210 having flared guiding walls 220 for guiding the retainer 70 into its retainer opening 60.
As best seen in FIGURE 2, the body 12 further has a second and like prong recess 300 which is like the recess 20 and is disposed alongside and preferably parallel to the recess 20, the retainer opening 60 extending through the body 12 to the second prong recess 300 and extending into the second prong recess 300 a distance such that the innermost end of the retainer 70 extends at least as far across the second recess 300 as above described as necessary for retaining the prong 34 in the prong recess 20.
Preferably the prong recess 60 has a lowermost end 360 forming a socket 362 in the body 12 entering from the second prong recess 300 for receiving the lowermost end 360 of the retainer 70 such that it extends into the recess 362 so that the retainer 70 tends to be supported by the walls of the socket 362 to further brace the retainer 70 to prevent the removal of the prong 34 and prong 434.
As thus described, it is believed that this invention has provided a more economical plug block which is efficient in its operation and which fulfills the objectives above set forth.
1. A plug block electrical cord and plug assembly comprising an electrical plug, an electrical cord attached to said plug, said plug having two elongated projecting prongs each having a small prong opening extending through its outer end, said small prong openings being equally spaced from outer ends of their respective prongs, said plug block having a body, a pair of prong recesses in a side of said body receiving said prongs, said body having a retainer opening extending through another side of said body, said retainer opening being in alignment with and extending to each of said prong recesses and extending transversely to said prong recesses, an elongated retainer disposed in said retainer opening and extending into said prong recesses and through said small prong openings to retain said prongs in said block, and releasable preventing means for preventing the removal of said retainer from its said prong retaining position, said body having a 'hasp opening therethrough, a padlock having its hasp extending through said hasp opening, the position of said hasp opening being such that said hasp opening and said padlock form parts of said releasable preventing means.
2. The combination of claim 1 in which said prong releasable preventing means comprises a prong retainer holder to which the outer end of said prong retainer is attached, said prong retainer holder having a dog opening extending therethrough in approximate parallelism with said elongated retainer, said body having a dog projecting therefrom and attached thereto in a position for extending through and beyond said dog opening at times when said retainer is in its prong retaining position, said dog having an outer portion provided with a hasp aperture therethrough for receiving the hasp of a padlock, said hasp aperture being disposed sufliciently close to said retainer receiving holder so as to cause a padlock hasp in said hasp aperture to prevent said retainer holder from moving away from said body sufiiciently to move said retainer out of retaining position with respect to said prong opening.
3. The combination of claim 1 in which said retainer opening extends completely through each of said prong recesses and into said body on the opposite side of said recesses from said other side of said body, and said retainer extending beyond said prong recesses on each side of each of said prong recesses whereby said retainer is well-supported against a pulling thereagainst by both prongs.
4. The combination of claim 1 in which attachment means is connected to the outer end of said retainer and of a cross-sectional area which is substantially larger than said retainer as measured in a direction normal to said retainer, said attachment means being movable with respect to said body when said hasp is removed from said hasp opening.
References Cited UNITED STATES PATENTS 783,653 2/1905 Tregoning 339-66 2,188,419 1/1940 Saviteer 70164 2,654,073 9/1953 Katz 339-37 2,733,416 1/1956 Evalt 33937 2,844,805 7/1958 Darrell 33937 MARVIN A. CHAMPION, Primary Examiner. J. H. McGLYNN, Assistant Examiner.
US. Cl. X.R.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US783653 *||Jun 13, 1904||Feb 28, 1905||Perkins Corp||Electrical plug-cut-out cover.|
|US2188419 *||Aug 3, 1938||Jan 30, 1940||Saviteer Raymond H||Condolence receptacle|
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|US2733416 *||Apr 5, 1955||Jan 31, 1956||Locking device for use with electrical|
|US2844805 *||Feb 17, 1956||Jul 22, 1958||Darrell George H||Plug locking and protecting device|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3662320 *||Dec 24, 1970||May 9, 1972||Marx Arthur J||Plug lock|
|US4181395 *||Feb 24, 1978||Jan 1, 1980||Walter Grabowski||Connector for electrical components to be installed in flush receptacle boxes|
|US4204723 *||Jan 26, 1979||May 27, 1980||Bloomingdale Jack W||Safety plug clip|
|US4308730 *||Mar 17, 1980||Jan 5, 1982||Roth Donald P||Electrical plug locking device|
|US4347412 *||Jan 3, 1980||Aug 31, 1982||Mitsubishi Denki Kabushiki Kaisha||Handle lock device for a switch|
|US4407554 *||Mar 16, 1981||Oct 4, 1983||Drall Jerry E||Electrical plug safety device|
|US4413488 *||Dec 22, 1980||Nov 8, 1983||Iowa State University Research Foundation, Inc.||Electrical appliance lock|
|US4563048 *||Jan 11, 1985||Jan 7, 1986||Im Kwan S||Locking device for an electrical plug|
|US4946401 *||Nov 17, 1989||Aug 7, 1990||Tomei Thushin Kogyo Co., Ltd.||Connecting block for telephone|
|US5176527 *||Dec 14, 1990||Jan 5, 1993||E. I. Du Pont De Nemours And Company||Apparatus for preventing the use of an electrical device|
|US5277600 *||Apr 30, 1992||Jan 11, 1994||Meixler Lewis D||Electrical plug safety lock|
|US5288239 *||Nov 12, 1992||Feb 22, 1994||Johnson Jack L||Device for preventing the theft of electrical appliances|
|US5591038 *||Feb 17, 1994||Jan 7, 1997||Panduit Corp.||Plug lockout|
|US5795166 *||Feb 23, 1995||Aug 18, 1998||Meixler; Lewis D.||Self contained child resistant electrical plug safety lock|
|US6159025 *||Feb 8, 2000||Dec 12, 2000||Derman; Jay S||Electric cord plug lock|
|US6398589||Sep 7, 2000||Jun 4, 2002||Richard A. Congelliere||Device for restricting operation of an electrical tool|
|U.S. Classification||439/134, 70/164, 70/57|
|Cooperative Classification||H01R13/447, H01R13/639|