Title:
SAFETY CORD PLUG ADAPTOR FOR ELECTRIC OUTLET BOXES
United States Patent 3775729
Abstract:
A safety protective cover for electrical wall outlet includes hollow housing, and means for releasably affixing same over at least one plug-in receptacle of outlet with plug-in electric cord extending from housing. Stop means on cord and housing, after plugging cord in receptacle and subsequent attachment of housing to wall outlet, effective independently of the plug to prevent unplugging of the same due to a child tugging on the cord.
US Patent References:
Guard for flush wall outlets
Monaco - February 1947 - 2415602
Protective cover for electrical outlets
Gregg - October 1950 - 2526606
Protective cover for appliance plugs
Low - June 1960 - 2942226
Safety plug lock
Thaw - December 1962 - 3067402
Pilferproof wall plate
Protzmann - December 1964 - 3159446
Guard for flush wall outlets
Monaco - February 1947 - 2415602
Protective cover for electrical outlets
Gregg - October 1950 - 2526606
Protective cover for appliance plugs
Low - June 1960 - 2942226
Safety plug lock
Thaw - December 1962 - 3067402
Pilferproof wall plate
Protzmann - December 1964 - 3159446
Application Number:
05/249079
Publication Date:
11/27/1973
Filing Date:
05/01/1972
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
439/371, 174/67
International Classes:
H01R13/639; H01R13/54
Field of Search:
339/39,75.79,82 174/67
Primary Examiner:
Mcglynn, Joseph H.
Claims:
What is claimed is
1. A cover for an electrical wall outlet as for locking attachment of an electric extension-cord plug to a receptacle of the outlet comprising; a housing including at least one hollow, generally cup-shaped part having peripheral and outer-end wall portions; means on said housing for affixing the same to the wall at the outlet with a said cup-shaped part in cupped relationship over a said receptacle; aperture means provided in said cup-shaped part adjacent the inner end thereof for wedging reception of a cord plug inwardly therethrough while the housing is free of the wall outlet; slot means provided in the wall portions of said cup-shaped part to communicate with said aperture means and extending to a said outer end wall, for permitting inward passage of the cord to extend through said outer-end wall portion, whereby said housing is attachable to the wall outlet with the cord extended from the end wall portion, subsequent to attachment of the cord plug to the fixed receptacle; and stop means adapted to be carried by a portion of said cord within said cup-shaped part for engagement with said outer-end wall portion for restraining outwardly applied tension on the cord which would otherwise tend to effect removal of the plug from the wall outlet, said stop member having staggered portions for wedging reception of the cord.
2. A cover for a wall outlet as in claim 1, wherein said stop member is shaped for snug complemental reception in the hollow of said cup-shaped part, said stop member having irregular passage means extending inwardly of a side thereof for adjusted inward wedging reception of the cord therethrough.
3. A cover for a wall outlet as in claim 1, the hollow of said cup-shaped part terminating in a seat portion for stop reception of said stop member affixed on the cord.
4. A cover for a wall outlet as in claim 3, said stop member and said seat portion being shaped for snug complemental reception of the stop member in said seat portion.
5. A cover for a wall outlet as in claim 4, said stop member being a cube-shaped block and said staggered portions thereof defining angularly disposed connecting passages in which the cord is wedgingly gripped.
6. A cover for an electrical wall outlet as for locking attachment of an electrical extension-cord plug to a receptacle of the outlet comprising: a housing including at least one hollow, generally cup-shaped part having peripheral and outer-end wall portions; and a base plate affixed to the housing, an aperture means being provided in housing for communicating with the hollow of said at least one cup-shaped part, in a position of affixed attachment of the base plate with the housing when positioned over the receptacle, and adapted to contain a said plug in said position of locking attachment thereof with reference to the receptacle; means associated with said housing including staggered portions defining a zig-zag passage for tight zig-zag wedging for reception of a portion of the extension cord to extend outwardly from the hollow of the housing, thereby to anchor the cord to the housing against removal of the plug from the receptacle as by pulling action applied to the cord.
1. A cover for an electrical wall outlet as for locking attachment of an electric extension-cord plug to a receptacle of the outlet comprising; a housing including at least one hollow, generally cup-shaped part having peripheral and outer-end wall portions; means on said housing for affixing the same to the wall at the outlet with a said cup-shaped part in cupped relationship over a said receptacle; aperture means provided in said cup-shaped part adjacent the inner end thereof for wedging reception of a cord plug inwardly therethrough while the housing is free of the wall outlet; slot means provided in the wall portions of said cup-shaped part to communicate with said aperture means and extending to a said outer end wall, for permitting inward passage of the cord to extend through said outer-end wall portion, whereby said housing is attachable to the wall outlet with the cord extended from the end wall portion, subsequent to attachment of the cord plug to the fixed receptacle; and stop means adapted to be carried by a portion of said cord within said cup-shaped part for engagement with said outer-end wall portion for restraining outwardly applied tension on the cord which would otherwise tend to effect removal of the plug from the wall outlet, said stop member having staggered portions for wedging reception of the cord.
2. A cover for a wall outlet as in claim 1, wherein said stop member is shaped for snug complemental reception in the hollow of said cup-shaped part, said stop member having irregular passage means extending inwardly of a side thereof for adjusted inward wedging reception of the cord therethrough.
3. A cover for a wall outlet as in claim 1, the hollow of said cup-shaped part terminating in a seat portion for stop reception of said stop member affixed on the cord.
4. A cover for a wall outlet as in claim 3, said stop member and said seat portion being shaped for snug complemental reception of the stop member in said seat portion.
5. A cover for a wall outlet as in claim 4, said stop member being a cube-shaped block and said staggered portions thereof defining angularly disposed connecting passages in which the cord is wedgingly gripped.
6. A cover for an electrical wall outlet as for locking attachment of an electrical extension-cord plug to a receptacle of the outlet comprising: a housing including at least one hollow, generally cup-shaped part having peripheral and outer-end wall portions; and a base plate affixed to the housing, an aperture means being provided in housing for communicating with the hollow of said at least one cup-shaped part, in a position of affixed attachment of the base plate with the housing when positioned over the receptacle, and adapted to contain a said plug in said position of locking attachment thereof with reference to the receptacle; means associated with said housing including staggered portions defining a zig-zag passage for tight zig-zag wedging for reception of a portion of the extension cord to extend outwardly from the hollow of the housing, thereby to anchor the cord to the housing against removal of the plug from the receptacle as by pulling action applied to the cord.
Description:
BACKGROUND OF INVENTION
Heretofore, protective covers for electrical outlets have been suggested in the prior art, ostensibly for the purpose of preventing small children from removing extension cord plugs from the outlets by pulling on the cords. Such devices of known types, however, have failed as safety means because, by relatively slight pulling effort applied to a cord, the lug thereon could be pulled from the electrical receptacle, and/or entirely separated from the plug with resultant possible danger of electrical sparking and/or electrical shock. Some such devices provided in connected segments were capable of accidental separation in use, and/or were difficult and expensive to manufacture.
SUMMARY OF DISCLOSURE
According to the present invention, the improved protective cover includes a one-piece housing which may be provided with spaced generally cup-shaped parts, each extending from a flat base member provided with attachment means for affixing the same to an electrical wall outlet with said cup-shaped housing parts in cupped relationship over plug-in receptacles of known types on the outlets. Each said housing part may be provided with aperture means in a peripheral wall portion thereof near the base member thereof, and extending into said base member, if necessary, for insertion of a cord plug inwardly through such aperture means while the housing is free of wall outlet. Slot means also may be provided in said peripheral wall portions of the respective housing parts to communicate with said aperture means thereof, and extend to outer end walls of the respective housing parts for permitting radially inward passage of the cords to extend through the respective end wall portions, whereby said housing can be attached to the wall outlet as a unit to have the cords extended from the respective end wall portions subsequent to attachment of the cord plugs to the respective fixed receptacles. Adjustable stop means is provided within each said housing part for restraining outwardly by applied tension on the cord which otherwise would be likely to effect unwanted removal of the plug from the wall outlet. In other words, the main purpose of the present invention is to prevent the cords from being unplugged from the wall outlets without first removing the adaptor from the same.
A general object of the present invention is to provide a unitary protective cover of the character described which can only be removed from a wall outlet by a relatively mature person, and in which means is provided to prevent small children from unplugging extension cords from the wall outlet by tugging or pulling on the cord.
Another object of the invention is to provide a protective cover of the character described which lends itself to economical production, such as by use of a two-piece sectional cavity mold.
Other objects of the invention will be manifest from the following brief description and the accompanying drawings.
Of the accompanying drawings:
FIG. 1 is a front elevation of a molded protective cover, partly broken away and in section, embodying the features of the invention and illustrating the cover in position for screw attachment thereof to a wall to overlie an electrical wall outlet, with pronged plugs of extension cords inserted into plug-in outlet receptacles in known manner.
FIG. 2 is a horizontal cross-section, on the same scale, taken substantially on the line 2--2 of FIG. 1, and illustrating the manner of insertion and removal of a cord plug by means of chain-dotted and full lines.
FIG. 3 is an end elevation of the protective cover as viewed from the right of FIG. 2, and on the same scale.
FIG. 4 is a perspective view of a stop member for selective attachment to an extension cord, and interlocking reception within hollow portions of the protective cover.
FIG. 5 is a perspective view corresponding to FIG. 4, illustrating a modified form of stop member in selective fixed attachment to an extension cord.
Referring to the drawings generally, and to FIGS. 1 to 3 in particular, the numeral 10 designates a one-piece protective cover, of hard molded plastic for example, adapted for fixed attachment to an electrical outlet E in a wall W, the outlet being of known type usually provided with two spaced plug-in receptacles R. The cover 10 includes a rectangular base plate 11, adapted to overlie the outlet E, and spaced cup-shaped housings 12, 12 integral with the plate 11 for presenting hollow chambers 13, 13 of the housings in overlying communication with the spaced receptacles R. The cover 10 may be secured to the outlet E by means of a screw 14 adapted to be inserted through an aperture 15 in the base plate 11, at a point centrally thereof between the housings 12, and threaded into the electrical outlet 3 in known manner as best shown in FIG. 2.
Each cup-shaped housing part 12 may be of molded rigid plastic, in the shape of a frustum of a pyramid for example, to have four connecting side walls 16, 16 defining the chamber 13, which is closed by a top wall 17. The wall 16 of each housing 12, at corresponding ends of the plate 11, may have therein an aperture 18, which can be extended into the plate 11 if necessary, through which aperture a pronged plug P on an electric extension cord C may be inserted, as indicated in chain-dotted lines in FIG. 2, prior to securing the cover 10 to the outlet E.
Stop means may be adjustably affixed or provided on the respective cord C, after it is passed through the aperture 18 and after the plug P is plugged into an outlet R, to be engageable with upper portions of the housing 16, and thereby prevent withdrawal of the cord beyond a given extent thereof. For this purpose, a cube-shaped block 20 of suitable material, such as hard plastic, may be provided with angular slot means extending part way through the block, generally as shown in FIG. 4, and defining angularly disposed, passage wall means, for adjustable zig-zag distortion wedging reception of the cord C through the block 20, as shown in FIG. 2. When the cord is selectively and fixedly adjusted on the block, the cord plug P is adapted to be plugged into the respective receptacle R, after which the protective cover 10 may be positioned on to the outlet E and attached thereto by means of the screw 14. When so positioning the cover 10, the stop block 20 is easily adjustable into full seating thereof within a complementally shaped recess 21 in the respective housing part 12.
Other stop means may be employed in place of the cube shaped block 20, such as a three-pronged E-shaped stop 23 as shown in FIG. 5. The device 23 would be wedgingly adjusted on the cord C, by looping the cord as before, to prevent extension of cord C through the top wall 17 of the respective housing part 12. The stop 23, like the stop 20, may be proportioned for either loose or wedging reception in the housing recesses 21, so long as the stop prevents removal of the cord plug P from the receptacle R and/or separation of the cord C from the plug P. The same apertured housing walls 16 may also have a narrow slot 19 therethrough, extending from the respective apertures 18 to the center of the corresponding top wall 17. This arrangement is such that, with the protective cover 10 unattached with reference to the wall outlet E, the plug P can be readily inserted through the aperture 18 of a housing part 12, after which the cord C can be passed through the connecting slot 19, to permit extension of the cord through the top wall 17 as shown in FIGS. 1 to 3.
In use of the protective cover 10 described above to prevent a small child from pulling the extension cords C from receptacles R of the electrical outlet E, the cord plugs P are inserted endwise through the apertures 18, prior to attachment of the cover to the outlet, as shown in chain dotted lines in FIG. 2. The cube-shaped stop members 20, are then wedgingly affixed to the cords C in closely spaced relationship to the plugs P, as previously described and then the plugs are forcibly inserted into the receptacles R, in known manner.
Next, with the plugs P so inserted, the cords C are fed into the slots 19 and drawn upwardly until the stop members 20 are complementally received and seated within the recesses 21 when, at the same time, the plate 11 is seated over the outlets E, as shown in FIGS. 1 to 3, whereby the cords C extend freely axially outwardly of the free ends of the respective housing parts, as shown in full lines in FIGS. 1 to 3. Upon accomplishing this positioning of the protective cover 10, it is readily secured firmly against the wall W, by means of the screw 14 as shown in FIG. 2.
With the protective cover 10 so affixed, a small child, upon pulling or tugging on a cord C, can only meet with resistance of the anchored stop 20 (or 23), without affecting the plugged-in condition of cord plug P. Accordingly, the present invention obviates the previously experienced danger of a small child being able to unplug an extension cord by tugging on the same.
Modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims. As an example, it is readily apparent that the stop means 20 and 23, shown in FIGS. 4 and 5, may be supplanted by means of tight knots tied in the cords C per se requisitely spaced from the plugs P to be in stop engagement with the outer walls 17 of the housing as before, and thereby to prevent removal of the plugs from the outlets E.
Heretofore, protective covers for electrical outlets have been suggested in the prior art, ostensibly for the purpose of preventing small children from removing extension cord plugs from the outlets by pulling on the cords. Such devices of known types, however, have failed as safety means because, by relatively slight pulling effort applied to a cord, the lug thereon could be pulled from the electrical receptacle, and/or entirely separated from the plug with resultant possible danger of electrical sparking and/or electrical shock. Some such devices provided in connected segments were capable of accidental separation in use, and/or were difficult and expensive to manufacture.
SUMMARY OF DISCLOSURE
According to the present invention, the improved protective cover includes a one-piece housing which may be provided with spaced generally cup-shaped parts, each extending from a flat base member provided with attachment means for affixing the same to an electrical wall outlet with said cup-shaped housing parts in cupped relationship over plug-in receptacles of known types on the outlets. Each said housing part may be provided with aperture means in a peripheral wall portion thereof near the base member thereof, and extending into said base member, if necessary, for insertion of a cord plug inwardly through such aperture means while the housing is free of wall outlet. Slot means also may be provided in said peripheral wall portions of the respective housing parts to communicate with said aperture means thereof, and extend to outer end walls of the respective housing parts for permitting radially inward passage of the cords to extend through the respective end wall portions, whereby said housing can be attached to the wall outlet as a unit to have the cords extended from the respective end wall portions subsequent to attachment of the cord plugs to the respective fixed receptacles. Adjustable stop means is provided within each said housing part for restraining outwardly by applied tension on the cord which otherwise would be likely to effect unwanted removal of the plug from the wall outlet. In other words, the main purpose of the present invention is to prevent the cords from being unplugged from the wall outlets without first removing the adaptor from the same.
A general object of the present invention is to provide a unitary protective cover of the character described which can only be removed from a wall outlet by a relatively mature person, and in which means is provided to prevent small children from unplugging extension cords from the wall outlet by tugging or pulling on the cord.
Another object of the invention is to provide a protective cover of the character described which lends itself to economical production, such as by use of a two-piece sectional cavity mold.
Other objects of the invention will be manifest from the following brief description and the accompanying drawings.
Of the accompanying drawings:
FIG. 1 is a front elevation of a molded protective cover, partly broken away and in section, embodying the features of the invention and illustrating the cover in position for screw attachment thereof to a wall to overlie an electrical wall outlet, with pronged plugs of extension cords inserted into plug-in outlet receptacles in known manner.
FIG. 2 is a horizontal cross-section, on the same scale, taken substantially on the line 2--2 of FIG. 1, and illustrating the manner of insertion and removal of a cord plug by means of chain-dotted and full lines.
FIG. 3 is an end elevation of the protective cover as viewed from the right of FIG. 2, and on the same scale.
FIG. 4 is a perspective view of a stop member for selective attachment to an extension cord, and interlocking reception within hollow portions of the protective cover.
FIG. 5 is a perspective view corresponding to FIG. 4, illustrating a modified form of stop member in selective fixed attachment to an extension cord.
Referring to the drawings generally, and to FIGS. 1 to 3 in particular, the numeral 10 designates a one-piece protective cover, of hard molded plastic for example, adapted for fixed attachment to an electrical outlet E in a wall W, the outlet being of known type usually provided with two spaced plug-in receptacles R. The cover 10 includes a rectangular base plate 11, adapted to overlie the outlet E, and spaced cup-shaped housings 12, 12 integral with the plate 11 for presenting hollow chambers 13, 13 of the housings in overlying communication with the spaced receptacles R. The cover 10 may be secured to the outlet E by means of a screw 14 adapted to be inserted through an aperture 15 in the base plate 11, at a point centrally thereof between the housings 12, and threaded into the electrical outlet 3 in known manner as best shown in FIG. 2.
Each cup-shaped housing part 12 may be of molded rigid plastic, in the shape of a frustum of a pyramid for example, to have four connecting side walls 16, 16 defining the chamber 13, which is closed by a top wall 17. The wall 16 of each housing 12, at corresponding ends of the plate 11, may have therein an aperture 18, which can be extended into the plate 11 if necessary, through which aperture a pronged plug P on an electric extension cord C may be inserted, as indicated in chain-dotted lines in FIG. 2, prior to securing the cover 10 to the outlet E.
Stop means may be adjustably affixed or provided on the respective cord C, after it is passed through the aperture 18 and after the plug P is plugged into an outlet R, to be engageable with upper portions of the housing 16, and thereby prevent withdrawal of the cord beyond a given extent thereof. For this purpose, a cube-shaped block 20 of suitable material, such as hard plastic, may be provided with angular slot means extending part way through the block, generally as shown in FIG. 4, and defining angularly disposed, passage wall means, for adjustable zig-zag distortion wedging reception of the cord C through the block 20, as shown in FIG. 2. When the cord is selectively and fixedly adjusted on the block, the cord plug P is adapted to be plugged into the respective receptacle R, after which the protective cover 10 may be positioned on to the outlet E and attached thereto by means of the screw 14. When so positioning the cover 10, the stop block 20 is easily adjustable into full seating thereof within a complementally shaped recess 21 in the respective housing part 12.
Other stop means may be employed in place of the cube shaped block 20, such as a three-pronged E-shaped stop 23 as shown in FIG. 5. The device 23 would be wedgingly adjusted on the cord C, by looping the cord as before, to prevent extension of cord C through the top wall 17 of the respective housing part 12. The stop 23, like the stop 20, may be proportioned for either loose or wedging reception in the housing recesses 21, so long as the stop prevents removal of the cord plug P from the receptacle R and/or separation of the cord C from the plug P. The same apertured housing walls 16 may also have a narrow slot 19 therethrough, extending from the respective apertures 18 to the center of the corresponding top wall 17. This arrangement is such that, with the protective cover 10 unattached with reference to the wall outlet E, the plug P can be readily inserted through the aperture 18 of a housing part 12, after which the cord C can be passed through the connecting slot 19, to permit extension of the cord through the top wall 17 as shown in FIGS. 1 to 3.
In use of the protective cover 10 described above to prevent a small child from pulling the extension cords C from receptacles R of the electrical outlet E, the cord plugs P are inserted endwise through the apertures 18, prior to attachment of the cover to the outlet, as shown in chain dotted lines in FIG. 2. The cube-shaped stop members 20, are then wedgingly affixed to the cords C in closely spaced relationship to the plugs P, as previously described and then the plugs are forcibly inserted into the receptacles R, in known manner.
Next, with the plugs P so inserted, the cords C are fed into the slots 19 and drawn upwardly until the stop members 20 are complementally received and seated within the recesses 21 when, at the same time, the plate 11 is seated over the outlets E, as shown in FIGS. 1 to 3, whereby the cords C extend freely axially outwardly of the free ends of the respective housing parts, as shown in full lines in FIGS. 1 to 3. Upon accomplishing this positioning of the protective cover 10, it is readily secured firmly against the wall W, by means of the screw 14 as shown in FIG. 2.
With the protective cover 10 so affixed, a small child, upon pulling or tugging on a cord C, can only meet with resistance of the anchored stop 20 (or 23), without affecting the plugged-in condition of cord plug P. Accordingly, the present invention obviates the previously experienced danger of a small child being able to unplug an extension cord by tugging on the same.
Modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims. As an example, it is readily apparent that the stop means 20 and 23, shown in FIGS. 4 and 5, may be supplanted by means of tight knots tied in the cords C per se requisitely spaced from the plugs P to be in stop engagement with the outer walls 17 of the housing as before, and thereby to prevent removal of the plugs from the outlets E.