Discharge lamp starting and operating circuit

• US 4,465,954 A
• Filed: 02/13/1984
• Issued: 08/14/1984
• Est. Priority Date: 05/10/1982
• Status: Expired due to Fees

• Current Assignee: GTE Products Corporation (Ams-Osram AG)
• Original Assignee: GTE Products Corporation (Ams-Osram AG)
• Inventors: Barakitis, Nikolaos, Cohen, Sheppard
• Primary Examiner(s): Dixon, Harold
• Application Number:
  US06/578,328
• Time in Patent Office: 183 Days
• Field of Search: 315/104, 315/101, 315/119, 315/125, 315/129, 315/35, 315/130, 315/73, 315/324
• US Class Current: 315/104
• CPC Class Codes: H01J 61/541 using a bimetal switch
• CPC Class Codes: H05B 41/04 Starting switches

Abstract

Apparatus for starting and operating a discharge lamp includes a starting device having bimetals and a rigid conductive member forming a switch, a ballast coupling the switch to an AC source and a discharge lamp and a spark gap each shunting the starting device with the starting device bimetals and rigid conductive device hermetically sealed in a vacuum.

Claims

1. A high intensity discharge lamp comprising

a first hermetically sealed envelope having a vacuum and a pair of support wires sealed into and extending therethrough;

a hermetically sealed arc tube disposed within said first envelope and having a pair of electrical leads sealed therein and extending therethrough with one of said pair of electrical leads of said arc tube connected to one of said pair of support wires of said first sealed envelope;

a starter device sealed in a vacuum and including a normally-closed (N/C switch coupled across said pair of support wires of said first sealed envelope and having first and second contacts with said first contact coupled by at least one bimetal and an electrical conductor to one of said pair of support wires and one of said pair of electrical leads and said second contact coupled to said support wire connected to said electrical lead; and

a spark gap means shunting said pair of electrical leads of said arc tube and having an arc over voltage greater than the breakdown voltage of said arc tube.

2. The high intensity discharge lamp of claim 1 wherein said spark gap means includes a series-connected spark gap and resistor.

3. The high intensity discharge lamp of claim 1 wherein said starter device is disposed within said vacuum of said first hermetically sealed envelope.

4. The high intensity discharge lamp of claim 1 wherein said spark gap means is located within said first hermetically sealed envelope.

5. The high intensity discharge lamp of claim 1 wherein said spark gap means includes a spark gap enclosed within a second hermetically sealed envelope positioned within said first hermetically sealed envelope.

6. The high intensity discharge lamp of claim 1 wherein said first contact is coupled by a first bimetal to one of said pair of support wires and by a second bimetal to one of said pair of electrical leads and a second contact is coupled to said support wire connected to said electrical lead.

7. Apparatus for starting and operating a high intensity discharge lamp having hermetically sealed and evacuated outer envelope comprising:

a pair of terminals formed for connection to an AC line source;

a lead circuit ballast coupled to one of said pair of terminals;

a starter device sealed in a vacuum and having a normally-closed (N/C) switch shunting said discharge lamp, said switch having a first contact coupled by a first bimetal and an electrical conductor to said lead ballast and to said discharge lamp and a second contact coupled to the other one of said pairs of terminals and to said discharge lamp; and

a spark gap means connected in shunt with and having an arc-over voltage greater than the break-down voltage of said discharge lamp.

8. The apparatus of claim 7 wherein said spark gap means includes a series connected spark gap and resistor.

9. The apparatus of claim 7 wherein said spark gap means has an arc-over voltage greater than the break-down voltage of said discharge lamp and less than an apparatus damage voltage.

10. The apparatus of claim 7 wherein said starter device is contained within said hermetically sealed and evacuated outer envelope of said high intensity discharge lamp.