Supply coupling of a fluorescent lamp

• US 6,504,318 B1
• Filed: 01/25/2001
• Issued: 01/07/2003
• Est. Priority Date: 03/30/1999
• Status: Expired due to Term

• Current Assignee: Innoware Oy
• Original Assignee: Innoware Oy
• Inventors: Pienisaari, Heikki
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): TRAN, CHUC
• Application Number:
  US09/701,327
• Time in Patent Office: 712 Days
• Field of Search: 315/120, 315/129, 315/291, 315/307, 315/DIG.2, 315/DIG.4, 315/DIG.5, 315/242, 315/219, 315/223, 315/226, 315/243, 323/355, 323/358, 323/359, 323/247
• US Class Current: 315/242
• CPC Class Codes: H05B 41/2985 against abnormal lamp operating conditions

Abstract

The invention relates to a supply coupling of a fluorescent lamp used for supervising the operation and condition of a lamp circuit, particularly a supply coupling in connection with an electronic coupling device wherein the power required by the lamp circuit is supplied to the coupling by a transformer. The supply coupling comprises a supply transformer (T1), a resonance circuit comprising the secondary coil (N2) of the transformer (T1) and a capacitor (C1) connected in parallel with the secondary coil, and a fluorescent tube (Lamp 1) connected in parallel with the resonance circuit and comprising fluorescent cathodes (F1, F2). The coupling further comprises a direct-current supply (DC) arranged to supply direct current (I_DC) through a circuit comprising a first fluorescent cathode (F1) of the fluorescent tube, a secondary coil (N2) of the supply transformer (T1), a second fluorescent cathode (F2) of the fluorescent tube (Lamp 1) and an indicator circuit (A) arranged to detect the presence of said direct current (I_DC) and to generate a signal indicating that presence to be used for controlling a coupling device of the fluorescent lamp.

Claims

1. A supply coupling of a fluorescent lamp comprising a supply transformer (T1), a resonance circuit comprising a secondary coil (N2) of the transformer (T1) and a capacitor (C1) connected in parallel with the secondary coil (N2), and a fluorescent tube (Lamp1) connected in parallel with the resonance circuit and comprising fluorescent cathodes (F1, F2), the coupling further comprising a direct-current supply (DC) arranged to supply direct current (IDC) through a circuit comprising the first fluorescent cathode (F1) of the fluorescent tube, the secondary coil (N2) of the supply transformer (T1), the second fluorescent cathode (F2) of the fluorescent tube (Lamp1) and an indicator circuit (A) arranged to detect the presence of said direct current (IDC) and to generate a signal indicating that presence to be used for controlling the coupling device of the fluorescent lamp.

2. A supply coupling as claimed in claim 1, wherein the signal indicates the presence of said direct current (I_DC), the signal being generated by the indicator circuit (A) being a current or voltage signal.