Emergency sign

Patent 4682147 Issued on July 21, 1987. Estimated Expiration Date:

November 12, 2006. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3659179

3795818

3869639

Self-contained maintenance-free emergency lighting
Patent #: 4071749
Issued on: 01/31/1978
Inventor: Balogh

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Inventor: Fahey

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Issued on: 11/03/1981
Inventor: Okuno

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Hysteresis type battery charger having output short circuit protection
Patent #: 4386308
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More ...

Inventor

Bowman, Norman E.

Assignee

Don Gilbert Industries, Inc.

Application

No. 06/929514 filed on 11/12/1986

US Classes:

340/815.45, Using light emitting diodes307/66, Storage battery or accumulator315/86, AUTOMATIC SUBSTITUTION OF THE POWER SUPPLY40/570Exit

Examiners

Primary: Caldwell, Sr., John W.
Assistant: Queen, Tyrone

International Classes

G08B 5/22 (20060101)
G08B 5/38 (20060101)
G08B 5/36 (20060101)

Abstract

An illuminated exit sign having a plurality of series connected light emitting diodes arranged to form the word "exit" and a control circuit for supplying power to the series connected diodes from line power and, during power failures, from battery power. The control circuit illuminates the diodes continuously during normal operation and alternately switches the diodes on and off during a power failure.