Flasher string

• US 6,396,219 B1
• Filed: 10/05/2000
• Issued: 05/28/2002
• Est. Priority Date: 10/05/2000
• Status: Expired due to Fees

• Current Assignee: Ti-Ming Tang
• Original Assignee: Ti-Ming Tang
• Inventors: Tang, Ti-Ming
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): Lee, Wilson
• Application Number:
  US09/680,398
• Time in Patent Office: 600 Days
• Field of Search: 315/185 S,185 R,200 A,312-324,49-60,94,226,95-101
• US Class Current: 315/185.00S
• CPC Class Codes: H05B 39/09 in which the lamp is fed by pulses automatic circuit devices built into or on the incandescent lamp H01K1/625; vehicle winking devices B60Q1/38

Abstract

A flasher string which includes a plurality of flashers connected in series and a plurality of thyrsitor diodes, each thyrsitor diode connected to a respective flasher in parallel. The flasher can periodically turn on and off to produce a twinkling light due to thermal distortion of the metal piece in the flasher. When the flasher turns on, the metal piece normally contacting the filament of the flasher is heated to expand and then escapes from the filament so as to turn off the flasher. Sequentially, the metal piece is cooled down to shrink back the original shape and contacts the filament to turn on the flasher again. The respective thyristor diode in parallel with the flasher is used to sustain the current when the flasher is off so as to minimize the impact of abrupt current change on the flasher string for a longer lifetime.

Claims

1. A lamp string comprising:

a plurality of lamps connected in series, each lamp having a tungsten filament, a lamp filament and a metal piece normally contacting said tungsten filament, said metal piece being thermally distorted and disconnected from said tungsten filament when said metal piece is heated;

a plurality of thyristor diodes each being connected in parallel with one of said plurality of lamps and maintaining a terminal voltage near a threshold voltage when the metal piece and the tungsten filament of the corresponding lamp connected in parallel are disconnected;

wherein each thyristor diode maintains a substantially stable and low current without an abrupt change when a positive or negative voltage across said thyristor diode is greater than said threshold voltage.

2. A lamp string as claimed in claim 1 further comprising a diode connected in series with said plurality of lamps, said diode rectifying an AC power source for reducing power consumption of said lamp string.