Safety plug adapter

• US 4,484,185 A
• Filed: 08/12/1983
• Issued: 11/20/1984
• Est. Priority Date: 08/12/1983
• Status: Expired due to Fees

• Current Assignee: Graves, James D.
• Original Assignee: Graves, James D.
• Inventors: Graves, James D.
• Primary Examiner(s): Rowland, James L.
• Assistant Examiner(s): Myer, Daniel
• Application Number:
  US06/522,764
• Time in Patent Office: 466 Days
• Field of Search: 340/656, 339/75 R, 339/75 M, 339/75 MP, 339/75 P, 339/76, 339/77, 339/78, 339/79, 339/82, 339/84, 339/103 R, 339/104, 339/105, 339/36, 174/66, 174/67, 337/1, 337/3, 337/4, 337/5, 337/72, 337/197, 337/198, 337/79, 337/241, 337/242, 337/265, 337/266, 337/332, 337/376
• US Class Current: 340/656
• CPC Class Codes: H01R 13/639 Additional means for holding or locking coupling parts together, after engagement, e.g. separate keylock, retainer strap
• CPC Class Codes: H01R 13/66 Structural association with built-in electrical component coupling devices having concentrically or coaxially-arranged contacts H01R24/38
• CPC Class Codes: H01R 13/713 the switch being a safety switch
• CPC Class Codes: H01R 13/717 with built-in light source
• CPC Class Codes: H01R 13/7175 Light emitting diodes (LEDs)
• CPC Class Codes: H01R 31/065 with built-in electric apparatus

Abstract

A safety plug to an outlet box receptacle, which includes an overcurrent protection device, and engaging devices for engaging the safety plug adapter both to flanged portions of the outlet box face plate and to the electric cord so that it is difficult for a small child to remove the electric cord connecting plug from the adapter, or the adapter from the outlet box receptacle. The adapter may also include a voltage-actuated light-emitting device to indicate when the outlet box receptacle is energized, and a spring-loaded adapter receptacle cover plate.

Claims

1. In combination, an outlet face plate assembly and a safety plug adapter for an electrical outlet box containing at least one receptacle for receiving a single phase, three prong, polarized electric plug, each receptacle having three recessed contacts for engaging the three plug prongs, respectively, the three receptacle contacts including a first contact connected to an energized line of a power system, a second contact connected to a ground line of the power system, and a third contact separately connected to ground, wherein the face plate assembly defines an access opening to each receptacle and includes first and second flanged portions disposed on opposite sides of each access opening and mounting means for securing the face plate to the outlet box, and the safety plug adapter comprises:

an adapter housing formed of electrically-insulating material;

first, second, and third contact prongs, extending outwardly from one end of the housing, which are shaped and spaced relative to one another to engage the first, second, and third receptacle contacts in said electrical outlet box, respectively;

fourth, fifth and sixth contact members secured within the adapter housing at an opposite end thereof from said first, second and third contact prongs and spaced the same as the first, second and third contact prongs, respectively, the adapter housing and the fourth, fifth and sixth contact members constituting another receptacle for receiving a single phase, three prong, polarized electric plug;

a first electrically conductive connecting line for connecting the first contact prong and the fourth contact member, which includes an overcurrent protection means in said first electrically conductive connecting line for opening the first connecting line upon the occurrence of an overcurrent flowing therethrough, and a reset means for resetting said overcurrent protection means upon opening,

second and third electrically conductive connecting lines for connecting the second and third contact prongs with the fifth and sixth contact members, respectively;

first and second resilient engaging means, disposed on opposite sides of the housing, for engaging the safety plug adapter with the face plate, the first and second engaging means having first ends affixed to the housing, and second ends for resiliently engaging the first and second flanged portions, respectively, of the face plate assembly; and

restraining means, affixed to the adapter housing, for holding an electrically insulating cover means against the opposite end of the adapter housing relative to said prongs in a position at which the adapter receptacle openings are covered by the cover means.

2. A combination, as described in claim 1, wherein the cover means is a single phase electric cord plug which is inserted into the adapter receptacle, and the restraining means comprises at least one elongate flexible member having one end affixed to the adapter housing and an opposite end adapted for connection to the electric cord adjacent the plug thereof to prevent removal of said plug.

3. A combination, as described in claim 1, wherein:

the cover means is a receptacle cover plate

which is movably disposed on the adapter housing at the opposite end thereof;

the safety plug adapter further comprises guide means, disposed at the opposite end of the adapter housing, for movably connecting the receptacle cover plate to the adapter housing for movement between a closed position at which the receptacle cover plate covers the adapter receptacle openings and an opened position at which an electric cord plug may be inserted into the adapter receptacle; and

the restraining means comprises spring means for exerting a bias force on the receptacle cover plate to maintain the receptacle cover plate in its closed position.

4. A combination, as described in claim 3, wherein the safety plug adapter further comprises at least one elongate flexible member having one end affixed to the adapter housing and an opposite end adapted for connection to an electric cord having a connection plug inserted into the adapter receptacle.

5. A combination, as described in claim 1, wherein the safety plug adapter further comprises voltage-actuated, light emitting means, disposed on one side of the adapter housing and electrically connected between the first and second contact prongs for indicating voltage therebetween.

6. A combination, as described in claim 5, wherein the safety plug adapter further comprises a fuse disposed in the second connecting line having a higher current rating than the overcurrent protection means.

7. A combination, as claimed in claim 6, in which:

said adapter includes a second light emitting means which is electrically connected to said first connecting line between said overcurrent protection means and said fourth contact member, and to said second connecting line between said fuse and said fifth contact member in order to determine operability of said fuse and said overcurrent protection means.

8. A combination, as described in claim 1, wherein the safety plug adapter further comprises a fuse disposed in the second connecting line having a higher current rating than the overcurrent protection means.

9. A combination, as described in claim 1, wherein the first connecting line of the safety plug adapter further comprises switch means connected in series with the overcurrent protection means.

10. A combination, as described in claim 1, wherein the overcurrent protection means is a switching means which is actuated by an overcurrent flowing therethrough to open the first connecting line, the switching means including a manual re-set button extending through an opening defined by the adapter housing on one side thereof.

11. A combination, as described in claim 1, wherein the overcurrent protection means is a fuse.