Electrical extension cord with capability for multi-positional fixed mounting

Information

  • Patent Grant
  • 6485327
  • Patent Number
    6,485,327
  • Date Filed
    Friday, October 12, 2001
    22 years ago
  • Date Issued
    Tuesday, November 26, 2002
    21 years ago
Abstract
An electrical extension cord assembly including a cord having a male plug attached to one end and a female receptacle head attached to the other end of the cord. The receptacle head is configured so that it can removably engage a base plate that is attached to a stationary object.
Description




REFERENCE TO A COMPUTER PROGRAM APPENDIX




Not Applicable




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates generally to electrical extension cords, and more particularly to an extension cord apparatus that can be reversibly mounted in multiple positions to mounting plates in a variety of locations.




2. Description of the Background Art




Electrical extension cords are commonplace in home and commercial settings. Conventional extension cords normally include two or three wires within a insulating jacket that are connected at one end to a male plug and at the other end to a head that contains one or more female receptacles. Extension cord heads fall into two general classes; namely, those that can be permanently mounted on a surface, and those that are non-mountable.




Mountable extension cords are advantageous in commercial applications such as construction sites where loose extension cords can be extremely dangerous. Typically, extension cord heads known in the art are mounted in one of two ways.




First, the head can include an eyelet through which a fastener, e.g., a screw or nail, can be installed to hold the head to a stationary object such as a wall. The durability of the head is limited by the strength of the eyelet that may tear if the extension cord is pulled.




The second type of mounting system has a head with a keyhole slot in the back of the head. The keyhole slot allows the head to slide over the head of a screw that has been partially screwed into a surface. This type of mounting also lacks durability and the attachment to the surface is not very secure.




In the first configuration described above, the head is securely fastened to the stationary object, but it cannot be easily detached. In contrast, the second configuration described above provides a means by which the head can be detached, but does not provide a very secure connection between the head and the stationary object.




Accordingly, there is a need for an extension cord assembly that can be securely attached to a stationary object during use and be detached relatively easily from the object and transferred to another location.




BRIEF SUMMARY OF THE INVENTION




An extension cord assembly according to the present invention includes an electrical cord that defines a first end and a second end. A male plug is attached to the first end of the electrical cord and a female receptacle head is attached to the second end of the electrical cord. The receptacle head preferably includes a plurality of female electrical receptacles. The female receptacle can be formed in a flat surface of the head or in a beveled surface formed by the head. The extension cord assembly further includes a base plate that can be attached to a stationary object. In turn, the receptacle head can be removably attached to the base plate.




Preferably, the receptacle head is formed with a dovetail-shaped groove and the base plate is formed with a correspondingly dimensioned dovetail-shaped tongue. The tongue of the base plate slidably engages the groove of the receptacle head to secure the receptacle head to the base plate. Conversely, in one embodiment, the groove is formed within the base plate and the tongue is present on the receptacle head. Or, in lieu of a tongue-and-groove configuration, the receptacle head can include two tabs that engage two correspondingly sized and shaped slots formed by the base plate in order to snap the receptacle head to the base plate.




In a preferred embodiment, the cord assembly includes a locking mechanism that engages the receptacle head to lock the receptacle head to the base plate. Preferably, the locking mechanism includes two tabs that engage two notches formed by the receptacle head. The tabs are movable between a locked position wherein the receptacle head cannot be removed from the base plate and an unlocked position wherein the receptacle head can be slidably removed from the base plate. In a preferred embodiment, the locking mechanism also includes a button for moving the tabs into the unlocked position.




In another aspect of the present invention, the extension cord assembly includes an electrical cord that defines a first end and a second end. A male plug is attached to the first end of the electrical cord and a female receptacle head is attached to the second end of the electrical cord. The receptacle head includes a female receptacle. This aspect of the present invention further includes a base plate and means for attaching the base plate to a stationary object. Moreover, this aspect includes means for removably attaching the receptacle head to the base plate.




In yet another aspect of the present invention, a female receptacle head for an extension cord includes means for removably engaging the female receptacle head with a base plate.




Further objects and advantages of the invention will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the invention without placing limitations thereon.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will be more fully understood by reference to the following drawings that are for illustrative purposes only:





FIG. 1

is a perspective view of an electrical extension cord assembly according to the present invention.





FIG. 2

is an exploded perspective view of the electrical extension cord assembly of

FIG. 1

showing the head detached from the base plate.





FIG. 3

is an exploded side view of the electrical extension cord assembly shown in FIG.


2


.





FIG. 4

is a side view of the embodiment of the extension cord head shown in FIG.


1


.





FIG. 5

is a front view of a base plate shown in FIG.


2


.





FIG. 6

is a perspective view of an alternative embodiment of a receptacle head according to the present invention.





FIG. 7

is an end view of the alternative receptacle head of FIG.


6


.





FIG. 8

is a side view of a second alternative embodiment of a receptacle head and base plate according to the present invention.





FIG. 9

is a front view of the second alternative receptacle head of FIG.


8


.





FIG. 10

is a side view of an alternative mounting system according to the present invention.





FIG. 11

is a side view of a second alternative mounting system according to the present invention.





FIG. 12

is a side view of a third alternative mounting system according to the present invention.





FIG. 13

is a front view of a locking mechanism for an extension cord assembly of

FIG. 1

in the locked position.





FIG. 14

is a front view of the locking mechanism of

FIG. 13

in the unlocked position.





FIG. 15

is a side view of the locking mechanism of FIG.


13


.





FIG. 16

is a front view of an alterative locking mechanism for an extension cord assembly of

FIG. 1

in the locked position.





FIG. 17

is a front view of the alternative locking mechanism of

FIG. 1

in the unlocked position.





FIG. 18

is a side view of the alternative locking mechanism of FIG.


16


.





FIG. 19

is a rear view of an extension cord head.











DETAILED DESCRIPTION OF THE INVENTION




Referring more specifically to the drawings, for illustrative purposes the present invention is embodied in the apparatus generally shown in FIG.


1


through FIG.


19


. It will be appreciated that the apparatus may vary as to configuration and as to details of the parts without departing from the basic concepts as disclosed herein.




Referring initially to FIG.


1


through

FIG. 5

, an electrical extension cord assembly


10


is generally shown. It can be seen in FIG.


1


through

FIG. 5

that the extension cord assembly


10


preferably includes a three-wire electrical cord


12


having a standard three prong, one-hundred and twenty volt (120v) male plug


14


affixed to one end and a female receptacle head


16


attached to the other end.




Returning to FIG.


1


through

FIG. 5

, it is shown that the extension cord assembly


10


further includes a base plate


18


to which the head


16


can be removably attached. As shown in

FIG. 2

,

FIG. 3

, and

FIG. 5

, in a preferred embodiment, the base plate


18


is formed with four holes


20


through which fasteners


22


, e.g., screws, bolts, nails, etc., can be inserted in order to attach the base plate


18


to a stationary object such as a wall.




It can be seen in FIG.


1


through

FIG. 5

that the receptacle head


16


is generally box shaped and has a front face


24


, a rear face


26


, a top face


28


, a bottom face


30


, a left end face


32


, and a right end face


34


. As shown, the rear face


26


, the top face


28


, and the bottom face


30


are each formed with a generally dovetail-shaped groove


36


.




On the other hand, the base plate


18


is formed with a dovetail-shaped tongue


38


that is sized to be received within any of the grooves


36


formed in the receptacle head


16


. It can be appreciated that the receptacle head


16


can be removably attached to the base plate


18


by sliding the receptacle head


16


relative to the base plate


18


such that one of the grooves


36


formed in the receptacle head


16


slides over the tongue


38


formed by the base plate


18


.




Thus, when the receptacle head


16


is properly disposed on the base plate


18


it will be held in a fixed position. Moreover, if necessary, the receptacle head


16


can be easily detached from the base plate


18


by sliding the receptacle head


16


relative to the base plate


18


until the groove


36


completely disengages the tongue


38


. It is to be understood that the receptacle head


16


is preferably formed with three grooves


26


, as shown, to allow the receptacles, described below, that are formed in the front face of the receptacle head


16


to be oriented in three directions relative to the base plate


18


, e.g., facing up, facing down, and facing forward relatively to a vertical base plate


18


.




As shown, the head


16


can be a multi-tap head, i.e., the head


16


is formed with plural female receptacles


39


. Conversely, the head


16


can be a single-tap head, i.e., the head


16


is formed with only a single female receptacle. It is to be understood that the preferred cord assembly


10


is configured to transmit power from standard 120v alternating current (AC) wall outlets to devices that operate using 120v AC. However, the cord assembly


10


may be easily modified to work in conjunction with nearly any type of outlet and device plug.




FIG.


6


and

FIG. 7

show an alternative receptacle head generally designated


40


. In this embodiment, the receptacle head


40


includes a plurality of female receptacles


42


formed in a front face


44


of the head


40


and one female receptacle


42


formed in a right end face (not shown) of the receptacle head


40


. As shown in FIG.


6


and

FIG. 7

, the receptacle head


40


is formed with a single dovetail slot


46


in a rear face


48


of the head


40


. Thus, the receptacle head


40


can only be mounted in one direction relative to a base plate, e.g., the base plate


18


shown in FIG.


1


through FIG.


5


.




Referring now to FIG.


8


and

FIG. 9

, a second alternative receptacle head is shown and generally designated


50


. FIG.


8


and

FIG. 9

show that this embodiment of the receptacle head


50


includes a front face


52


surrounded by four beveled faces


54


. As shown, each face


52


,


54


can be preferably formed with two female receptacles


56


. Moreover, as shown in FIG.


8


and

FIG. 9

, a dovetail-shaped tongue


58


extends from a rear face


55


at the back of the receptacle head


50


opposite the front face


52


. The dovetail-shaped tongue


58


is configured to engage a dovetail shaped groove


60


formed in a base plate


62


. Thus, the receptacle head


50


can be removably attached to the base plate


62


. Also, each face


52


,


54


of the receptacle head


50


provides female receptacles


56


oriented in five directions relative to the base plate


62


, i.e., facing up, facing down, facing left, facing right, and facing forward relative to a vertical base plate


62


.




FIG.


10


through

FIG. 12

show three alternative mounting systems for the electrical extension cord assembly of the present invention, e.g., the preferred extension cord assembly


10


shown in FIG.


1


through FIG.


5


. Specifically,

FIG. 10

shows a base plate


70


formed with a dovetail-shaped groove


72


. A receptacle head


74


is formed with four ears


76


at each corner of the receptacle head


74


and extend along the length of the receptacle head


74


, i.e., into the page looking at FIG.


10


. These ears


76


can engage the groove


72


two at a time in order to securely fasten the receptacle head


74


to the base plate


70


.





FIG. 11

shows a base plate


80


that is formed with a dovetail-shaped groove


82


flanked by an upper tab


84


and a lower tab


86


. These tabs


84


,


86


extend along the entire length of the groove


82


, i.e., into the page looking at FIG.


11


. As shown in

FIG. 11

, a receptacle head


88


is formed with a rectangular slot


90


in each corner of the generally box-shaped receptacle head


88


. Moreover, a dovetail-shaped tongue


92


is formed between each consecutive pair of slots


90


so that there are four tongues


92


around the perimeter of the receptacle head


88


. Accordingly, the receptacle head


88


can slidably engage the base plate


80


so that it will be securely fastened thereto. In other words, each tongue


92


can be inserted one at a time in the groove


82


while the tabs


84


,


86


that flank the groove


82


fit into the slots


90


that flank each tongue


92


.




In another alternative mounting system, shown in

FIG. 12

, a base plate


100


can be formed with a rectangular indentation


102


that is sized and shaped so that a receptacle head


104


can be partially inserted into the base plate


100


. A slot


106


is formed at each end of the rectangular indentation


102


. Further, as shown, three tabs


108


extend perpendicularly from each end of the receptacle head


104


along the longitudinal axis so that there are six tabs


108


total with three opposing pairs. In accordance with this embodiment, the tabs


108


fit into the slots


106


to allow the receptacle head


104


to be snapped in place within the indentation formed by the base plate


100


.




Referring now to FIG.


13


through

FIG. 15

a locking mechanism is shown and generally designated


120


. The locking mechanism


120


is used to prevent a receptacle head, e.g., the receptacle head


16


shown in FIG.


1


through

FIG. 5

, from sliding off of a base plate, e.g., the base plate


18


also shown in FIG.


1


through FIG.


5


. As shown, the locking mechanism


120


includes an upper generally triangular-shaped tab


122


and a lower generally triangular-shape tab


124


. The base of the upper tab


122


is connected to the base of the lower tab


124


by a relatively thin, flat diaphragm


126


. The narrow ends of the tabs


122


,


124


maintain contact with a locking mechanism support face


128


established by the base plate


18


adjacent to an inner cavity


129


therein. As shown, the tabs


122


,


124


extend from within the interior of the base plate


18


through respective openings


130


,


132


formed by the base plate


18


. Thus, the tabs


122


,


124


can engage corresponding notches, described below, that are formed by the receptacle head


16


.




FIG.


13


through

FIG. 15

further show that a release button


134


is installed within the end of the base plate


18


so that one end of the button


134


is external to the base plate


18


and the other end contacts the diaphragm


128


. As shown, a spring


136


is installed in compression between the diaphragm


126


and the support face


128


.




As shown in

FIG. 14

, when the button


134


is depressed, the diaphragm


126


is bent at the center. In turn, the tabs


122


,


124


pivot about their narrow ends that contact the support face


128


. This causes the base of each tab


122


,


124


to be drawn into the interior of the base plate


18


. Thus, the locking mechanism


120


is in the unlocked position and the receptacle head


16


can be slidably removed from the base plate


18


. When the button


134


is released the spring


136


returns the locking mechanism


120


to the locked position shown in FIG.


13


.




FIG.


16


through

FIG. 18

show an alternative locking mechanism generally designated


140


. As shown, this embodiment of the locking mechanism


140


includes a base


142


having an upper arm


144


and a lower arm


146


extending perpendicularly therefrom. Additionally, an upper ramped tab


148


extends outwardly, i.e., up, from the upper arm


144


and a lower ramped tab


150


extends outwardly, i.e., down, from the lower arm


146


. FIG.


16


through

FIG. 18

also show that the ends of each arm


144


,


146


include respective push plates


152


,


154


that allow a user to unlock the mechanism


140


, as described in detail below.




As shown in FIG.


16


and

FIG. 17

, the base plate


18


is formed with an interior cavity


156


in which the locking mechanism


140


can be installed. The base plate


18


also establishes a locking mechanism support face


158


against which the locking mechanism


140


rests when installed in the interior cavity


156


of the base plate


18


. Additionally, the base plate


18


forms an upper tab opening


160


and a lower tab opening


162


. As shown, when the locking mechanism


140


is installed in the base plate


18


, the push plates


152


,


154


attached to the arms


144


,


146


and a portion of each ramped tab


148


,


150


extend outside the interior cavity


156


of the base plate


18


. The ramped tabs


148


,


150


engage respective notches, described below, that are formed by a receptacle head such as the receptacle head


16


shown in FIG.


1


through FIG.


5


.




When a user squeezes the push plates


152


,


154


toward each other, the ramped tabs


148


are moved into the interior cavity


156


of the base plate


18


. Thus, the locking mechanism


140


is in the unlocked position, shown in

FIG. 17

, and the receptacle head


16


can be slidably removed from the base plate


18


. When the push plates


152


,


154


are released, the arms


144


,


146


return to their original positions so that the locking mechanism


140


is in the locked position shown in FIG.


16


.




Referring now briefly to

FIG. 19

, the back of a receptacle head, such as the receptacle head


16


described in conjunction with FIG.


1


through

FIG. 5

, is shown.

FIG. 19

shows that the receptacle head


16


is formed with an upper notch


170


and a lower notch


172


. These notches


170


,


172


are configured to engage the tabs


122


,


124


,


148


,


150


of either locking mechanism


120


,


140


in order to secure the receptacle head


16


to the base plate.




With the configuration of structure described below, it can be appreciated that the present invention provides a means by which a female receptacle head of an extension cord can be relatively easily attached to and removed from a base plate. Also, a relatively secure connection is provided between the receptacle head and the base plate.




Accordingly, it will be seen that this invention is an extension cord apparatus that has a cord head configured to reversibly engage a base plate that is mounted to the underside of a table, a wall or other convenient location. The head can be positioned at convenient points of access rather than placed on the floor or ground to be potentially exposed to water or dust or the like. Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Therefore, it will be appreciated that the scope of the present invention fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” All structural, chemical, and functional equivalents to the elements of the above-described preferred embodiment that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112, sixth paragraph, unless the element is expressly recited using the phrase “means for.”



Claims
  • 1. An extension cord assembly, comprising:an electrical cord having at least two wires; said electrical cord having a first end and a second end; a male plug attached to said first end of said electrical cord; a receptacle head attached to said second end of said electrical cord; said receptacle head including at least one female receptacle; a base plate; said base plate being attachable to a stationary object; said receptacle head being removably attachable to said base plate; and a locking mechanism associated with said base plate; wherein said locking mechanism is engageable with said receptacle head to lock said receptacle head to said base plate; wherein said locking mechanism includes at least two tabs engageable with at least two corresponding notches formed by said receptacle head; and wherein said tabs are movable between a locked position wherein said receptacle head cannot be removed from said base plate and an unlocked position wherein said receptacle head can be slidably removed from said base plate.
  • 2. An extension cord assembly as recited in claim 1;wherein said receptacle head is formed with at least one groove; wherein said base plate is formed with at least one tongue; and wherein said tongue is slidably engageable with said groove to secure said receptacle head to said base plate.
  • 3. An extension cord assembly as recited in claim 2, wherein said tongue and groove are dovetail shaped.
  • 4. An extension cord assembly as recited in claim 1, wherein said locking mechanism further comprises at least one button for moving said tabs into said unlocked position.
  • 5. An extension cord assembly as recited in claim 1:wherein said receptacle head defines a first end and a second end; wherein said receptacle head further includes at least one tab extending from said first end and at least one tab extending from said second end opposite said first tab; and wherein said base plate includes at least two slots configured to engage said tabs; and wherein said receptacle head is snapping engageable with said base plate.
  • 6. An extension cord assembly as recited in claim 1, wherein said receptacle head includes at least one beveled surface in which said female receptacle is established.
  • 7. An extension cord assembly as recited in claim 1:wherein said receptacle head is formed with at least one tongue; wherein said base plate is formed with at least one groove; and wherein said tongue is slidably engageable with said groove to secure said receptacle head to said base plate.
  • 8. An extension cord assembly as recited in claim 7, wherein said tongue and groove are dovetail shaped.
  • 9. An extension cord assembly, comprising:an electrical cord having at least two wires; said electrical cord having a first end and a second end; a male plug attached to said first end of said electrical cord; a receptacle head attached to the second end of the electrical cord; said receptacle head including at least one female receptacle; said receptacle head formed with at least one groove; a base plate; said base plate being attachable to a stationary object; said base plate formed with at least one tongue; said tongue slidably engageable with said groove to secure said receptacle head to said base plate; and a locking mechanism associated with said base plate; wherein said locking mechanism is engageable with said receptacle head to lock said receptacle head to said base plate; wherein said locking mechanism includes at least two tabs engageable with at least two corresponding notches formed by said receptacle head; and wherein said tabs are movable between a locked position wherein said receptacle head cannot be removed from said base plate and an unlocked position wherein said receptacle head can be slidably removed from said base plate.
  • 10. An extension cord assembly as recited in claim 9, wherein said tongue and groove are dovetail shaped.
  • 11. An extension cord assembly as recited in claim 9, wherein said locking mechanism further comprises at least one button for moving said tabs into said unlocked position.
  • 12. An extension cord assembly as recited in claim 9:wherein said receptacle head has a first end and a second end; wherein said receptacle head further includes at least one tab extending from said first end and at least one tab extending from said second end opposite said first tab; wherein said base plate includes at least two slots configured to engage said tabs; and wherein said receptacle head is snapping engageable with said base plate.
  • 13. An extension cord assembly as recited in claim 9, wherein said receptacle head includes at least one beveled surface in which said female receptacle is established.
  • 14. An extension cord assembly, comprising:an electrical cord having at least two wires; said electrical cord having a first end and a second end; a male plug attached to said first end of said electrical cord; a receptacle head attached to said second end of said electrical cord; said receptacle head including at least one female receptacle; said receptacle head formed with at least one tongue; a base plate; said base plate being attachable to a stationary object; said base plate formed with at least one groove; said tongue being slidably engageable with said groove to secure said receptacle head to said base plate; and a locking mechanism associated with said base plate; wherein said locking mechanism is engageable with said receptacle head to lock said receptacle head to said base plate; wherein said locking mechanism includes at least two tabs engageable with at least two corresponding notches formed by said receptacle head; and wherein said tabs are movable between a locked position wherein said receptacle head cannot be removed from said base plate and an unlocked position wherein said receptacle head can be slidably removed from said base plate.
  • 15. An extension cord assembly as recited in claim 14, wherein said tongue and groove are dovetail shaped.
  • 16. An extension cord assembly as recited in claim 14, wherein said receptacle head includes at least one beveled surface in which said female receptacle is established.
  • 17. An extension cord assembly, comprising:an electrical cord having at least two wires; said electrical cord having a first end and a second end; a male plug attached to said first end of the electrical cord; a receptacle head attached to said second end of said electrical cord; said receptacle head including at least one female receptacle; a base plate; means for attaching said base plate to a stationary object; means for removably attaching said receptacle head to said base plate; and a locking mechanism associated with said base plate; wherein said locking mechanism is engageable with said receptacle head to lock said receptacle head to said base plate; wherein said locking mechanism includes at least two tabs engageable with at least two corresponding notches formed by said receptacle head; and wherein said tabs are movable between a locked position wherein said receptacle head cannot be removed from said base plate and an unlocked position wherein said receptacle head can be slidably removed from said base plate.
  • 18. An extension cord assembly as recited in claim 17, further comprising: means for slidably engaging said receptacle head with said base plate.
  • 19. An extension cord assembly as recited in claim 17, further comprising: means for snapping engaging said receptacle head to said base plate.
  • 20. A female receptacle head for an extension cord, comprising:a cord head having at least one female receptacle; and means for removably engaging a base plate with said cord head; wherein a locking mechanism associated with said base plate is engageable with said receptacle head to lock said receptacle head to said base plate; wherein said locking mechanism includes at least two tabs engageable with at least two corresponding notches formed by said receptacle head; and wherein said tabs are movable between a locked position wherein said receptacle head cannot be removed from said base plate and an unlocked position wherein said receptacle head can be slidably removed from said base plate.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. provisional application Ser. No. 60/240,477 filed on Oct. 13, 2000, incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

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Provisional Applications (1)
Number Date Country
60/240477 Oct 2000 US