← Back to Patent Explorer
US3781597A Expired / Lapsed US ⏱️ 0.0 years remaining

Lighting device for a discharge lamp

Assignee: Toshiba Corp
•
Filing: 1972-11-28
•
Granted: 1973-12-25
•
Expires: 1992-11-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a lighting device for a discharge lamp including a ballast inserted between an AC power source and a discharge lamp the ratio ZC/ZL of the capacitive impedance ZC to the inductive impedance ZL of the ballast is in the range of 1.9-2.8; the ratio VL/VS of the nominal lamp voltage VL of a discharge lamp to the unloaded voltage VS of a power source is in the range of 0.7-1.1; and when VL/VS is in the range of 1.0-1.1, the ratio VL/VS is so determined as to satisfy the equation:

Inventors

  • 👤 O Nomura
  • 👤 K Yajima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 03:53
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/16; H05B41/20; H05B41/23; H05B41/232

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 109 words
A lighting device for a discharge lamp including a discharge lamp fed from an AC power source and a ballast arranged between the discharge lamp and the AC power source and including a capacitive impedance ZC and an inductive impedance ZL, in which a ratio ZC/ZL of the capacitive impedance ZC to the inductive impedance is in the range of 1.9-2.8; a ratio VL/VS of a nominal lamp voltage VL of the discharge lamp to an unloaded voltage VS of the power source is in the range of 0.7-1.1; and when the ratio VL/VS is in the range of 1.0-1.1 it satisfies the equation: ZC/ZL > OR = 9VL/VS-7.1.
Claim 2
Dependent Claim 109 words
A lighting device for a discharge lamp including a discharge lamp fed from an AC power source and a ballast arranged between the discharge lamp and the AC power source and including a capacitive impedance ZC and an inductive impedance ZL, in which a ratio ZC/ZL of the capacitive impedance ZC to the inductive impedance is in the range of 1.9-2.8; a ratio VL/VS of a nominal lamp voltage VL of the discharge lamp to an unloaded voltage VS of the power source is in the range of 0.7-1.1; and when the ratio VL/VS is in the range of 1.0-1.1 it satisfies the equation: ZC/ZL > OR = 9VL/VS-7.1.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-12-24 1977-06-25 1977-12-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-12-24 1981-06-25 1981-12-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-12-24 1985-06-25 1985-12-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag