Locking electrical receptacle with elongate clamping surfaces
A method and apparatus (“utility”) for securing an electrical connection formed by a mating structure including prongs of a male assembly and receptacles of a female assembly are provided. The utility includes a clamping mechanism whereby the very forces that would otherwise tend to pull the connection apart serve to actuate the clamping mechanism, thereby securing the mated pair. The apparatus may be integrated into a standard receptacle, or retrofitted to work with existing devices. In one embodiment, the clamping mechanism acts solely on the ground prong of a standard plug assembly, so that it is unnecessary to consider electrical potentials applied to the clamped prong in relation to the design of the clamping mechanism. Further, the withdrawing movement of the prongs of a plug may cause elongate clamping surfaces of the clamping mechanism to frictionally engage opposing surfaces of the clamped prong.
1. A locking electrical receptacle for use in conjunction with an electrical plug including at least one elongate extending plug structure comprising:
receptacle structure defining a receptacle for receiving said elongate extending elongate extending plug structure;
elongate gripping elements movably mounted on said receptacle structure, said gripping elements being disposed at least on opposite sides of said receptacle; and
actuation structure, operatively associated with said elongate gripping elements, for forcing said elongate gripping elements into secure frictional engagement with opposing surfaces of said elongate extending plug structure responsive to a withdrawal force exerted on electrical plug and urging said elongate extending plug structure to withdraw from said receptacle; and
release structure, operationally associated with said elongate gripping elements, for moving said elongate gripping elements to a release configuration so as to release said prongs from said secure frictional engagement.
2. A locking electrical receptacle according to claim 1 , wherein said actuation structure comprises at least one cross-member for interconnecting said gripping elements such that relative lateral movement of one of said gripping elements with respect to the other causes said gripping elements to be drawn towards one another so as to more firmly grip said elongate extending plug structure.
3. A locking electrical receptacle according to claim 2 , wherein said actuation structure comprises a plurality of cross-members pivotally interconnected to said gripping elements such that said gripping elements are constrained to maintain a substantially parallel relationship in connection with said relative lateral movement.
4. A locking electrical receptacle according to claim 3 , wherein said cross-members can lengthen under tension.
5. A locking electrical receptacle according to claim 4 , wherein said cross-members have an accurate shape that resiliently straightens under tension.
6. A locking electrical receptacle according to claim 1 , wherein said elongate extending plug structure comprises a prong having first and second side surfaces for making electrically conductive contact with contact surfaces within said receptacle, and top and bottom surfaces extending between said first and second side surfaces, and said elongate gripping elements are positioned so as to engage at least said top and bottom surfaces.
7. A locking electrical receptacle according to claim 1 , wherein said release mechanism is operative for reducing said frictional engagement of said gripping elements and said elongate extending plug structure when desired.
8. A locking electrical receptacle according to claim 7 , wherein said release mechanism comprises release structure for allowing a user to initiate relative longitudinal movement as between said gripping elements.
9. A locking electrical receptacle according to claim 8 , wherein said release structure comprises a receptacle housing shell mounted for telescopic movement with respect to a housing core, wherein one of said gripping elements is mounted in fixed relation to said core and another of said gripping elements moves in response to movement of said housing shell.
10. A locking electrical receptacle according to claim 1 , wherein said actuation structure is further operative for urging said elongate gripping elements into a receiving condition when said elongate extending plug structure is withdrawn from said receptacle, at least a portion of said gripping elements being separated by a distance less than a height between said opposing surfaces in said receiving condition.
11. A method for use in securing an electrical connection involving an electrical plug including at least one elongate extending plug structure, comprising the steps of:
providing an electrical receptacle unit including receptacle structure defining a receptacle for receiving said elongate extending plug structure, elongate gripping elements movably mounted on said receptacle structure and having a receiving condition, wherein said gripping elements are ready to receive said elongate extending plug structure, and a gripping condition, wherein at least one of said gripping elements is disposed in secure frictional engagement with said elongate extending plug structure and a release element for moving said gripping elements from said gripping condition to a release condition;
inserting said elongate extending plug structure of said electrical plug into said receptacle of said electrical receptacle unit such that said gripping elements are in said gripping condition;
operating said gripping element to move said gripping elements from said gripping condition to said release condition; and
removing said elongate extending plug structure of said electrical plug from said receptacle of said electrical receptacle unit.
12. A method as set forth in claim 11 , wherein said step of inserting comprises spreading said gripping elements apart.
13. A method as set forth in claim 11 , wherein said step of moving comprises causing relative longitudinal movement as between said gripping elements.
14. A method as set forth in claim 13 , wherein said electrical receptacle unit comprises a housing shell mounted for telescopic movement with respect to a housing core, and said step of causing comprises sliding said housing shell relative to said housing core.
15. A locking receptacle according to claim 1 , wherein said elongate gripping elements are integrated with electrical contacts for forwarding an electrical connection between said electrical receptacle and said electrical plug.