Compact screw-in fluorescent lamp

• US 6,172,464 B1
• Filed: 02/24/1995
• Issued: 01/09/2001
• Est. Priority Date: 08/14/1980
• Status: Expired due to Term

• Current Assignee: CFL Technologies LLC
• Original Assignee: Ole K Nilssen
• Inventors: Nilssen, Ole K.
• Primary Examiner(s): Shingleton, Michael B
• Application Number:
  US08/394,251
• Time in Patent Office: 2,146 Days
• Field of Search: 315/56, 315/71, 315/36, 315/DIG.4, 315/DIG.5, 315/DIG.7, 315/307, 315/291, 315/219, 315/209.R, 315/224, 315/205
• US Class Current: 315/56
• CPC Class Codes: H02M 7/53832 in a push-pull arrangement
• CPC Class Codes: H03K 3/30 using a transformer for feedback, e.g. blocking oscillator
• CPC Class Codes: H05B 41/245 for a plurality of lamps
• CPC Class Codes: H05B 41/28 using static converters
• CPC Class Codes: H05B 41/2827 using specially adapted components in the load circuit, e.g. feed-back transformers, piezoelectric transformers; using specially adapted load circuit configurations
• CPC Class Codes: H05B 41/2855 against abnormal lamp operating conditions
• CPC Class Codes: H05B 41/2856 against internal abnormal circuit conditions
• CPC Class Codes: H05B 41/295 with semiconductor devices and specially adapted for lamps with preheating electrodes, e.g. for fluorescent lamps
• CPC Class Codes: H05B 41/38 Controlling the intensity of light
• CPC Class Codes: H05B 41/3925 by frequency variation H05B41/3922 takes precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y10S 315/04 Dimming circuit for fluorescent lamps
• CPC Class Codes: Y10S 315/05 Starting and operating circuit for fluorescent lamp
• CPC Class Codes: Y10S 315/07 Starting and control circuits for gas discharge lamp using transistors

Abstract

In a high-frequency electronic ballast, a fluorescent lamp is connected with and powered by way of a series-resonant LC circuit. A resistive load is connected with the LC circuit, thereby to constitute a load therefor before ignition of the fluorescent lamp or in case the fluorescent lamp were to fail to ignite.

Claims

1. An arrangement comprising:

a screw-base inserted into and held by a lamp socket adapted to accept and hold an ordinary household incandescent light bulb;

the screw-base having base terminals and being otherwise characterized by having a central screw-base axis around which the outer boundary of the screw-base forms an approximately cylindrical surface;

the lamp socket having socket terminals at which is provided AC power line voltage such as that normally provided from an ordinary electric utility power line;

a fluorescent lamp having lamp terminals;

the fluorescent lamp being characterized by including at least two straight cylindrical light-emitting glass-enclosed sections disposed parallel to each other as well as to a central lamp axis;

a lamp terminal being disposed at one end of each of the two straight cylindrical light-emitting glass-enclosed sections;

the other ends of the two straight cylindrical light-emitting glass-enclosed sections being connected together via a transversely disposed light-emitting glass-enclosed section;

said transversely disposed section being of a maximum dimension substantially no longer than just sufficient to reach between said other ends;

electronic sub-assembly having power input terminals connected with the base terminals and power output terminals connected with the lamp terminals;

the sub-assembly being operative, whenever supplied with AC power line voltage at its power input terminals, to supply an alternating lamp current to the lamp terminals;

the alternating lamp current being of frequency distinctly higher than that of the AC power line voltage;

the sub-assembly being additionally characterized by not including a transformer having a primary winding connected across the power input terminals;

the electronic sub-assembly being further characterized by including two terminals across which exists a DC voltage having a substantially constant absolute magnitude that is distinctly higher than the peak absolute magnitude of the AC power line voltage; and

structure means operative to hold together the screw-base, the fluorescent lamp, and the electronic sub-assembly, thereby to form an integral screw-in lamp structure characterized by having an overall longitudinal axis parallel with the central screw-base axis as well as with the central lamp axis.

2. An arrangement comprising:

a screw-base inserted into and held by a lamp socket adapted to accept and hold an ordinary household incandescent light bulb;

the screw-base having base terminals and being otherwise characterized by having a central screw-base axis around which the outer boundary of the screw-base forms an approximately cylindrical surface;

the lamp socket having socket terminals at which is provided AC power line voltage such as that normally provided from an ordinary electric utility power line;

a fluorescent lamp having lamp terminals;

the fluorescent lamp being characterized by including at least two straight cylindrical light-emitting glass-enclosed sections disposed parallel to each other as well as to a central lamp axis;

a lamp terminal being disposed at one end of each of the two straight cylindrical light-emitting glass-enclosed sections;

the other ends of the two straight cylindrical light-emitting glass-enclosed sections being connected together via a transversely disposed light-emitting glass-enclosed section;

said transversely disposed section being of a maximum dimension substantially no longer than just sufficient to reach between said other ends;

electronic sub-assembly having power input terminals connected with the base terminals and power output terminals connected with the lamp terminals;

the sub-assembly being operative, whenever supplied with AC power line voltage at its power input terminals, to supply an alternating lamp current to the lamp terminals;

the alternating lamp current being of frequency distinctly higher than that of the AC power line voltage;

the sub-assembly being additionally characterized by not including a transformer having a primary winding connected across the power input terminals;

the electronic sub-assembly being further characterized by including a pair of terminals across which exists a DC voltage and between which are series-connected two transistors;

the transistors being characterized by alternatingly conducting current;

at least one of the transistors conducting current in the form of periodic unidirectional current pulses;

the periodic unidirectional current pulses occurring at a frequency equal to that of the alternating lamp current;

each individual unidirectional current pulse having a duration distinctly shorter than half of a complete period of the alternating lamp current; and

structure means operative to hold together the screw-base, the fluorescent lamp, and the electronic sub-assembly, thereby to form an integral screw-in lamp structure characterized by having an overall longitudinal axis parallel with the central screw-base axis as well as with the central lamp axis.

3. A structure characterized by having a central axis about which the following elements are assembled:

a screw-base operative to screw into a lamp socket of a type usually used for receiving and holding an ordinary household incandescent light bulb;

the screw-base being otherwise characterized by having base terminals and by being disposed symmetrically about the central axis;

a fluorescent lamp having lamp terminals and plural cylindrical lamp segments disposed apart from, but parallel to, each other as well as to the central axis;

each of the plural cylindrical lamp segments having a total length;

the fluorescent lamp being further characterized in that a flat plane disposed perpendicular to the central axis and intersecting one of the cylindrical lamp segments anywhere along its total length creates a cross-sectional pattern that (i) is symmetrical with respect to a flat plane disposed parallel to the central axis, and (ii) includes nothing but cross-sections of substantially identical cylindrical lamp segments;

an electronic sub-assembly having input terminals and output terminals;

the input terminals being connected with the base terminals;

the output terminals being connected with the lamp terminals;

the electronic sub-assembly being operative to supply an alternating voltage at its output terminals provided it be supplied with an AC power line voltage at its input terminals;

the frequency of the alternating voltage being distinctly higher than that of the AC power line voltage;

the electronic subassembly being additionally characterized by including a transistor through which flows unidirectional current pulses at a periodic rate equal to that of the alternating voltage;

each current pulse having a duration distinctly shorter than half of the complete cycle of the alternating voltage; and

housing means mounted rigidly on the screw-base and operative to house the electronic sub-assembly as well as to hold and support the fluorescent lamp, thereby to form a fluorescent lamp entity adapted to be screwed into and powered from a lamp socket at which ordinary AC power line voltage is provided.

4. A structure characterized by having a central axis about which the following elements are assembled:

a screw-base operative to screw into a lamp socket of a type usually used for receiving and holding an ordinary household incandescent light bulb;

the screw-base being otherwise characterized by having base terminals and by being disposed symmetrically about the central axis;

a fluorescent lamp having lamp terminals and plural cylindrical lamp segments disposed apart from, but parallel to, each other as well as to the central axis;

each of the plural cylindrical lamp segments having a total length;

the fluorescent lamp being further characterized in that a flat plane disposed perpendicular to the central axis and intersecting one of the cylindrical lamp segments anywhere along its total length creates a cross-sectional pattern that (i) is symmetrical with respect to a flat plane disposed parallel to the central axis, and (ii) includes nothing but cross-sections of substantially identical cylindrical lamp segments;

an electronic sub-assembly having input terminals and output terminals;

the input terminals being connected with the base terminals;

the output terminals being connected with the lamp terminals;

the electronic sub-assembly being operative to supply an alternating voltage at its output terminals provided it be supplied with an AC power line voltage at its input terminals;

the frequency of the alternating voltage being distinctly higher than that of the AC power line voltage;

the electronic subassembly being additionally characterized by including a pair of terminals across which exists a DC voltage having a substantially constant absolute magnitude that is distinctly larger than the absolute peak magnitude of the AC power line voltage; and

housing means mounted rigidly on the screw-base and operative to house the electronic sub-assembly as well as to hold and support the fluorescent lamp, thereby to form a fluorescent lamp entity adapted to be screwed into and powered from a lamp socket at which ordinary AC power line voltage is provided.

5. A structure characterized by having a central axis about which the following elements are assembled:

a screw-base operative to screw into a lamp socket of a type usually used for receiving and holding an ordinary household incandescent light bulb;

the screw-base being otherwise characterized by having base terminals and by being disposed symmetrically about the central axis;

a fluorescent lamp having lamp terminals and plural cylindrical lamp segments disposed apart from, but parallel to, each other as well as to the central axis;

each of the plural cylindrical lamp segments having a total length;

the fluorescent lamp being further characterized in that a flat plane disposed perpendicular to the central axis and intersecting one of the cylindrical lamp segments anywhere along its total length creates a cross-sectional pattern that (i) is symmetrical with respect to a flat plane disposed parallel to the central axis, and (ii) includes nothing but cross-sections of substantially identical cylindrical lamp segments;

an electronic sub-assembly having input terminals and output terminals;

the input terminals being connected with the base terminals;

the output terminals being connected with the lamp terminals;

the electronic sub-assembly being operative to supply an alternating voltage at its output terminals provided it be supplied with an AC power line voltage at its input terminals;

the frequency of the alternating voltage being distinctly higher than that of the AC power line voltage;

the electronic subassembly being additionally characterized by including a pair of terminals across which (i) exists a DC voltage, and (ii) are series-connected two filter capacitors; and

housing means mounted rigidly on the screw-base and operative to house the electronic sub-assembly as well as to hold and support the fluorescent lamp, thereby to form a fluorescent lamp entity adapted to be screwed into and powered from a lamp socket at which ordinary AC power line voltage is provided.

6. A structure characterized by having a central axis about which the following elements are assembled:

a screw-base operative to screw into a lamp socket of a type usually used for receiving and holding an ordinary household incandescent light bulb;

the screw-base being otherwise characterized by having base terminals and by being disposed symmetrically about the central axis;

a fluorescent lamp having lamp terminals and plural cylindrical lamp segments disposed apart from, but parallel to, each other as well as to the central axis;

each of the plural cylindrical lamp segments having a total length;

the fluorescent lamp being further characterized in that a flat plane disposed perpendicular to the central axis and intersecting one of the cylindrical lamp segments anywhere along its total length creates a cross-sectional pattern that (i) is symmetrical with respect to a flat plane disposed parallel to the central axis, and (ii) includes nothing but cross-sections of substantially identical cylindrical lamp segments;

an electronic sub-assembly having input terminals and output terminals;

the input terminals being connected with the base terminals;

the output terminals being connected with the lamp terminals;

the electronic sub-assembly being operative to supply an alternating voltage at its output terminals provided it be supplied with an AC power line voltage at its input terminals;

the frequency of the alternating voltage being distinctly higher than that of the AC power line voltage;

the electronic subassembly being additionally characterized by including a voltage-doubling rectifier assembly connected with the base terminals as well as with a pair of DC terminals across which exists a DC voltage of substantially constant magnitude;

which substantially constant magnitude is distinctly higher than the peak absoltr magnitude of the AC power line voltage; and

housing means mounted rigidly on the screw-base and operative to house the electronic sub-assembly as well as to hold and support the fluorescent lamp, thereby to form a fluorescent lamp entity adapted to be screwed into and powered from a lamp socket at which ordinary AC power line voltage is provided.