Visual indicator electrical plug-type surge protector and systems

• US 4,907,118 A
• Filed: 03/09/1989
• Issued: 03/06/1990
• Est. Priority Date: 03/09/1989
• Status: Expired due to Term

• Current Assignee: Curtis Computer Products Incorporated (ACCO Brands Incorporated)
• Original Assignee: Curtis Manufacturing Company Incorporated
• Inventors: Hames, Edward L.
• Primary Examiner(s): DEBOER, TODD
• Application Number:
  US07/321,590
• Time in Patent Office: 362 Days
• Field of Search: 361/56, 361/58, 361/111, 361/119, 361/127, 361/91, 361/104, 361/106, 340/638, 340/662, 340/653, 338/162, 338/227, 374/174, 374/161, 374/162, 337/28, 337/32, 337/243, 337/265, 337/24
• US Class Current: 361/56
• CPC Class Codes: H01R 13/6666 with built-in overvoltage protection
• CPC Class Codes: H01R 31/065 with built-in electric apparatus

Abstract

An inexpensive, compact, portable, visual indicator electrical plug-type surge protector which comprises an electrical plug body composed of a molded transparent polymer, the plug body having an extended male grounding prong and a pair of male electrical prongs on one face and a female receiving grounding inlet and a pair of female receiving inlets on the opposite face. The plug body contains in a visually indicating position, generally slightly below the surface of the plug body, a metal oxide varistor electrically connected to the electrical outlet plug so as to prevent electrical surges from passing through the surge protector from the electrical source into which the electrical plug-type surge protector is plugged and to be activated and to change color on the occurrence of an electrical surge so that the user of the surge protector will know when the electrical surge has been received and thereby be able to replace the surge protector with a new surge protector. Visual indicating surge protectors are designed to be plugged in to standard electrical apparatus or other sensitive electronic device which is to be protected from electrical surges.

Claims

1. A visual indicator electrical plug surge protector which comprises:

(a) a molded polymeric plug body;

(b) the plug body having on one face a grounding prong and a pair of parallel male electrical prongs, the grounding prong and the electrical prongs adapted to be inserted into an electrical output plug;

(c) The plug body having on an other face a female grounding plug inlet and a pair of female electrical plug inlets in electrical communication with the respective male grounding prong and male plug prongs and adapted to receive therein an electrical plug from an electrical apparatus which apparatus is to be protected from electrical surges from the electrical outlet plug; and

(d) a varistor means in electrical communication to act as a surge protector for electrical signals from the electrical outlet plug, the varistor means positioned close to the surface of the plug body to be visible to a plug user through a transparent part of the plug body and adapted to be activated and change color on the occurrence of an electrical surge whereby the user by visually observing the varistor means can determine if an electrical surge has occurred an can replace the said activated surge protector.

2. The surge protector of claim 1 wherein the plug body comprises a transparent polymer.

3. The surge protector of claim 1 wherein the varistor means comprises a metal oxide varistor

4. The surge protector of claim 3 wherein the metal oxide varistor comprises a flat circular material which changes to a dark color on activation.

5. The surge protector of claim 1 wherein the varistor means comprises a metal oxide varistor encapsulated in the transparent plug body and positioned slightly below the face of the plug body which face extends upwardly so that the varistor means is easily visible when the surge protector plug is inserted into the electrical outlet plug.

6. The surge protector of claim 1 wherein the said male prong outlets extend directly through the plug body and provide electrical contact with the female inlets.

7. The surge protector of claim 1 wherein the plug body comprises a generally transparent polymer and a thin layer of said polymer of the plug body extends over the outward surface of the varistor means.

8. The surge protector of claim 1 wherein the female and male inlets and outlets are on directly opposite faces of the plug body.

9. A surge protector system, which system comprises:

(a) the surge protector of claim 1;

(b) an electrical plug outlet connected to a source of electrical power and the male prongs of the said surge protector inserted into the electrical power outlet; and

(c) an electrical apparatus to be protected from electrical surges and having a line cord and a prong-type electrical plug at the one end of said line cord, the prong-type electrical plug having the prongs inserted into the female inlet of the said surge protector.

10. The system of claim 8 wherein the electrical apparatus comprises a telecopier, a telephone, a copying machine, modems, telex machine, personal computer or a printer.

11. A visual indicator electrical plug surge protector which comprises:

(a) a molded polymeric plug body comprising a generally transparent polymer and a thin layer of said polymer extends over the outward surface of the varistor means;

(b) the plug body having on one face a grounding prong and a pair of parallel male electrical prongs, the grounding prong and the electrical prongs adapted to be inserted into an electrical output plug;

(c) the plug body having on an other face a female grounding plug inlet and pair of female electrical plug inlets in electrical communication with the respective male grounding prong and male plug prongs and adapted to receive therein an electrical plug from an electrical apparatus which apparatus is to be protected from electrical surges from the electrical outlet plug; and

(d) a varistor means comprising a metal oxide varistor of a flat circular material which changes to a dark color on activation which is in electrical communication to act as a surge protector for electrical signals from the electrical outlet plug, the varistor means positioned slightly below the face of the transparent plug body which face extends upwardly so that the varistor means is easily visible when the surge protector plug is inserted into the electrical outlet plug and adapted to be activated and change to a dark color on the occurrence of an electrical surge whereby the user by visually observing the varistor means can determine if an electrical surge has occurred and can replace the said activated surge protector.