Flasher bulbs with shunt wiring for use in series connected light string with filament shunting in bulb sockets

• US 7,732,942 B2
• Filed: 02/11/2008
• Issued: 06/08/2010
• Est. Priority Date: 06/26/1995
• Status: Expired due to Fees

• Current Assignee: JLJ, Inc.
• Original Assignee: JLJ, Inc.
• Inventors: Janning, John L.
• Primary Examiner(s): Fleming; Fritz M
• Application Number:
  US12/029,329
• Publication Number:
  US 20080129213A1
• Time in Patent Office: 848 Days
• Field of Search: 362/211, 315/65, 315/66, 315/309, 315/185.S, 307/36
• US Class Current: 307/36
• CPC Class Codes: H01K 1/625 Flashing incandescent lamps
• CPC Class Codes: H05B 39/10 Circuits providing for substitution of the light source in case of its failure changing to a reserve current source H02J9/00

Abstract

A string set of series-connected incandescent bulbs in which substantially all of the bulb filaments in the set are individually provided with a shunt in their respective socket. If flasher bulbs are used in the string, they will twinkle off and on when the operating potential is applied. The flasher bulbs are provided with internal shunts to prevent all of the bulbs of the string from flashing on and off in the event of a failure of the shunt in the socket of the flasher bulb.

Claims

1. A series-wired light string powered by a line voltage, comprising:

a plurality of light bulbs including a plurality of flasher light bulbs that flash on and off completely, the flasher light bulbs being provided with internal shunt wiring comprising wiring extending between terminal posts inside each flasher light bulb, the wiring having an oxide coating that breaks down and causes the wiring to act as a shunt when the full line voltage appears across the terminal posts of the flasher bulb;

a plurality of light sockets connected in series, each light socket containing one of said plurality of flasher light bulbs; and

a plurality of voltage responsive shunts, each shunt disposed in a respective light socket containing a flasher light bulb and disposed outside of the respective flasher light bulb, each light socket shunt being electrically connected in parallel across a respective light socket for a flasher light bulb and having an “

on”

impedance approximately equal to the “

on”

impedance of the corresponding flasher light bulb in the socket to maintain the current passing through the light socket in the event that a flasher light bulb is inoperative or is missing from the light socket;

wherein, during operation of said light string and by operation of current passing through the light socket shunts containing flasher light bulbs when said flasher light bulbs are in the “

off”

state, said flasher light bulbs flash on and off completely at different rates and at different times to cause the light string to exhibit a twinkling effect; and

wherein, if a light socket shunt in a light socket containing one of said flasher light bulbs with internal shunt wiring should fail or become inoperative for any reason, the full line voltage will appear across the terminals of the flasher light bulb associated with that socket when the flasher light bulb flashes “

off,”

causing the internal shunt wiring to act as a shunt and short circuiting the associated flasher light bulb, preventing undesirable flashing of all light bulbs in the series-wired light string.

2. A method of operating a series-wired light string powered by a line voltage, the light string comprising a plurality of light bulbs including a plurality of flasher light bulbs that flash on and off completely, the flasher light bulbs being provided with internal shunt wiring extending between terminal posts inside each bulb, the wiring having an oxide coating that breaks down and causes the wiring to act as a shunt when the full line voltage appears across the terminal posts of the flasher bulb, connected in series, each light socket containing one of said plurality of flasher light bulbs, and a plurality of voltage responsive shunts, each shunt disposed in a respective light socket containing a flasher light bulb and disposed outside of the respective flasher light bulb, each light socket shunt being electrically connected in parallel across a respective light socket for a flasher light bulb and having an “

on”

impedance approximately equal to the “

on”

impedance of the corresponding flasher light bulb in the socket to maintain the current passing through the light socket in the event that a flasher light bulb is inoperative or is missing from the light socket, the method comprising coupling the line voltage to said series-wired light string, whereby the light socket shunts allow the series-wired light string to remain operative at all times regardless of whether any of said flasher light bulbs are inoperative or missing;

wherein, during operation of said light string, and by operation of current passing through the light socket shunts containing flasher light bulbs when said flasher light bulbs are in the “

off”

state, said flasher light bulbs flash on and off completely at different rates and at different times to cause the light string to exhibit a twinkling effect and

wherein, if a light socket shunt in a light socket containing one of said flasher light bulbs with internal shunt wiring should fail or become inoperative for any reason, the full line voltage will appear across the terminals of the flasher light bulb associated with that socket when the flasher light bulb flashes “

off,”

causing the internal shunt wiring to act as a shunt and short circuiting the associated flasher light bulb, preventing undesirable flashing of all light bulbs in unison in the series-wired light string.