JP3690577B2 - Light bulb shaped fluorescent lamp - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an inverter device, a fluorescent lamp lighting device, and a bulb-type fluorescent lamp.
[0002]
[Prior art]
In recent years, light bulb-type fluorescent lamps have been widely used as substitutes for general light bulbs, and the size has been reduced to a level corresponding to that of general light bulbs. The bulb-type fluorescent lamp usually uses a half-bridge type inverter circuit as a fluorescent lamp lighting device, and is miniaturized by simplifying the circuit configuration for controlling the inverter circuit. As an example, there is a fluorescent lamp lighting device disclosed in, for example, Japanese Patent Application Laid-Open No. 10-327584 (prior art), and its circuit configuration is shown in FIG.
[0003]
The fluorescent lamp lighting device 20 shown in FIG. 4 includes a complementary inverter circuit 21 including an N-channel transistor Q1 and a P-channel transistor Q2, and includes an inductor L4 and a capacitor C5 at both ends of the secondary winding L3a of the ballast choke L3. The resonance circuit 22 is formed, and both ends of the capacitor C5 are connected between the gates and sources of the N-channel transistor Q1 and the P-channel transistor Q2.
[0004]
When a current flows through the ballast choke L3, the resonance circuit 22 resonates and a resonance voltage is applied to both gates of the N-channel transistor Q1 and the P-channel transistor Q2. Further, when the direction of the current flowing through the ballast choke L3 changes, the polarity of the resonance voltage changes. The N-channel transistor Q1 is turned on when the gate voltage applied to the gate is greater than or equal to a predetermined positive value, and the P-channel transistor Q2 is turned on when the gate voltage is greater than or equal to a predetermined negative value. That is, when the N-channel transistor Q1 and the P-channel transistor Q2 are alternately turned on / off, the fluorescent lamp 23 is lit at a high frequency.
[0005]
[Problems to be solved by the invention]
In the fluorescent lamp lighting device 20, since the resonance circuit 22 is connected to both ends of the secondary winding L3a of the ballast choke L3, the inductor L4 is easily affected by the leakage magnetic flux of the ballast choke L3, and the inverter circuit 21 malfunctions. May occur. Therefore, the inductor L4 needs to be disposed on the circuit board at a position separated from the ballast choke L3. Increasing the distance between the components in this way impairs the degree of design freedom of the circuit board. This leads to an increase in the size of the circuit board and has a disadvantage that the bulb-type fluorescent lamp is increased in size.
[0006]
The present invention has been made in view of the above problems, and an object thereof is to provide a compact fluorescent lamp that can of be downsized circuit board is improved degree of freedom in designing the circuit board.
[0007]
[Means for Solving the Problems]
The bulb-type fluorescent lamp of the present invention includes a complementary transistor connected in series between output terminals of a DC power supply, a common reference node in which the reference nodes of the transistor are connected to each other, and a common control node in which the control nodes are connected to each other. a switching means having, the switching output of the switching means is connected to flow, and a fluorescent lamp lighting having both ends of the output winding is connected to a common reference node and the common control node saturable current transformer An inductive element for limiting the switching output of the switching means, a fluorescent lamp having a pair of electrodes connected via the inductance element between the switching outputs of the switching means, and a parallel connection between the electrodes of the fluorescent lamp; It consists of an inductance element and a starting capacitor that forms a series resonant circuit. A load circuit energized by the switching output of the switching means; a circuit board on which the fluorescent lamp lighting device and the circuit components of the load circuit are mounted; and having a base, supporting the circuit board, and fluorescence of the base and the circuit board And a base formed to be electrically connected to the lamp lighting device, wherein the inductance element and the saturable current transformer are arranged on the same surface side of the circuit board. .
[0008]
In the present invention and each of the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified.
[0009]
The DC power supply is a battery, a DC power supply device, a rectified or rectified and smoothed commercial AC voltage, a rectified and smoothed circuit connected to a commercial AC power supply by a rectifying and smoothing circuit and a chopper circuit, etc. Good.
[0010]
A complementary transistor is a series circuit of an N-channel transistor and a P-channel transistor. The drain of the N-channel transistor is the positive side of the DC power source, and the drain of the P-channel transistor is the negative side of the DC power source. Connected to DC power supply. Alternatively, the complementary transistor refers to a series circuit of an NPN transistor and a PNP transistor, and the collector of the NPN transistor is the positive side of the DC power source and the collector of the PNP transistor is the negative side of the DC power source. In addition, a diode is connected between the emitter and collector of each of the NPN transistor and the PNP transistor.
[0011]
The reference node of the complementary transistor refers to the source of the N-channel transistor and the source of the P-channel transistor, and the common reference node refers to the connection point between the source of the N-channel transistor and the source of the P-channel transistor. That means. Alternatively, the reference node of the complementary transistor refers to the emitter of the NPN transistor and the emitter of the PNP transistor, and the common reference node refers to the connection point of the emitter of the NPN transistor and the emitter of the PNP transistor.
[0012]
The control node of the complementary transistor refers to the gate of the N-channel transistor or the gate of the P-channel transistor, and the common control node refers to the connection between the gate of the N-channel transistor and the gate of the P-channel transistor. It means a point. Alternatively, the control node of the complementary transistor refers to the base of the NPN transistor or the base of the PNP transistor, and the common control node refers to the connection point of the base of the NPN transistor and the base of the PNP transistor.
[0013]
Load circuit, Ru der which operates the fluorescent lamp at a high frequency.
[0014]
According to the present invention, both ends of the output winding of the saturable current transformer are connected to the common reference node and the common control node of the complementary transistors, respectively. The switching means is switched to output a high frequency, and the load circuit is operated at the high frequency. Further, since the direction of the current flowing through the saturable current transformer changes due to resonance between the inductance element of the load circuit and the starting capacitor, the switching means performs a switching operation, and the fluorescent lamp is energized by the switching output.
[0015]
Since the saturable current transformer has only to connect both ends of the output winding to the common reference node and the common control node of the complementary transistor, the circuit connection pattern is simplified, and the same circuit board surface side as the inductance element is provided. Even if it is placed, it becomes easier to place it on the circuit board where it is not affected by the leakage magnetic flux of the inductance element, improving the degree of design freedom of the circuit board and reducing the size of the circuit board. A shaped fluorescent lamp can be provided.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0016]
FIG. 1 is a circuit diagram of an inverter device showing a first embodiment of the present invention. In the figure, 1 is an inverter device, 2 is an inverter circuit as switching means, and 3 is a load circuit. Since the inverter device 1 includes a fluorescent lamp FL or the like as the load circuit 3, it constitutes a fluorescent lamp lighting device 4.
[0017]
The inverter circuit 2 as a switching means is constituted by a complementary transistor connected in series between the output terminals 5a and 5b of the DC power supply 5. That is, in the series circuit of the N-channel transistor Tr1 and the P-channel transistor Tr2, the drain side of the N-channel transistor Tr1 is the positive side of the DC power supply 5 and the drain side of the P-channel transistor Tr2 is the negative side of the DC power supply 5. It is connected to the. The source is the reference node of the N-channel transistor Tr1 and the source of the P-channel transistor Tr2 are the common reference node a and the control node of the N-channel transistor Tr1 connected to each other. The gate is a control node of the P-channel transistor Tr2 and has a common control node b connected to each other. The output of the inverter circuit 2 is formed between the drain and source of the P-channel transistor Tr2. The inverter circuit 2 outputs a high frequency as a switching output by alternately turning on and off the N-channel transistor Tr1 and the P-channel transistor Tr2. Note that each of the N-channel transistor Tr1 and the P-channel transistor Tr2 includes parasitic diodes D1 and D2, as shown in the figure.
[0018]
A load circuit 3 is connected to the output side of the inverter circuit 2. The load circuit 3 includes an inductor L1 as an inductance element that limits the switching output of the inverter circuit 2, a DC cut capacitor C1 that removes a DC component of the switching output, and an inductor L1 and a DC cut between the outputs of the inverter circuit 2. A fluorescent lamp FL having a pair of filament electrodes FLa and FLb connected via a capacitor C1 and a start connected in parallel between the filament electrodes FLa and FLb of the fluorescent lamp FL to form a series resonance circuit with the inductor L1 And capacitor C2. The load circuit 3 is energized by the switching output of the inverter circuit 2.
[0019]
A primary winding L2a of the saturable current transformer L2 is connected between the inverter circuit 2 and the load circuit 3. Both ends of the secondary winding (output winding) L2b of the saturable current transformer L2 are connected to the common reference node a and the common control node b of the inverter circuit 2 via the resistor R1, respectively. Further, both ends of the secondary winding (output winding) L2b are connected to the capacitor C3 via the resistor R1.
[0020]
An activation circuit 6 is formed between the common reference node a and the common control node b of the inverter circuit 2 and the output terminal 5 a of the DC power supply 5. That is, a series circuit of a resistor R2 and a capacitor C4 is connected between the output terminal 5a and the common reference node a, and a trigger diode TD is connected between the connection point c of the resistor R2 and the capacitor C4 and the common control node b. Yes. The trigger diode TD becomes conductive when the voltage across the capacitor C4 exceeds a predetermined value. The voltage across the capacitor C4 is applied between the gate and source of the N-channel transistor Tr1, and the N-channel transistor Tr1 is turned on. A series circuit of a resistor R3 and a diode D3 is connected between the output terminal 5a and the connection point c with the output terminal 5a side in the forward direction. The capacitor C4 is charged when the N-channel transistor Tr1 is off, and discharged to the inverter circuit 2 side via the diode D3 when the N-channel transistor Tr1 is on.
[0021]
Next, the operation of the first embodiment will be described.
[0022]
When the DC power supply 5 is turned on, a current flows through the series circuit of the resistor R2 and the capacitor C4, and the capacitor C4 is charged. When the voltage across the capacitor C4 exceeds a predetermined voltage, the trigger diode TD is turned on. The voltage across the capacitor C4 is applied between the gate and source of the N-channel transistor Tr1, and the N-channel transistor Tr1 is turned on.
[0023]
When the N-channel transistor Tr1 is turned on, the DC power source 5, the output terminal 5a, the drain and source of the N-channel transistor Tr1, the common reference node a, the primary winding L2a of the saturable current transformer L2, the inductor L1, and the DC cut A current flows in the closed circuit of the capacitor C1, the filament electrode FLa of the fluorescent lamp FL, the starting capacitor C2, the filament electrode FLb of the fluorescent lamp FL, the output end 5b and the DC power source 5, and the DC cut capacitor C1 and the starting capacitor C2 Is charged and electromagnetic energy is stored in the inductor L1. A current flows from the resistor R1 to the capacitor C3 in the secondary winding L2b of the saturable current transformer L2, the capacitor C3 is charged, and a positive voltage is applied between the common reference node a and the common control node b. Is done. This positive voltage is a voltage for turning on the N-channel transistor Tr1. When the saturable current transformer L2 is saturated, no voltage is output to both ends of the secondary winding L2b, and due to the discharge of the capacitor C3, as shown in FIG. 2, between the gate and source of the N-channel transistor Tr1. The voltage (the voltage Vab between the common reference node a and the common control node b) decreases. When the gate-source voltage of the N-channel transistor Tr1 becomes equal to or lower than the predetermined voltage Vth, the N-channel transistor Tr1 is turned off.
[0024]
When the N-channel transistor Tr1 is turned off, the regenerative current due to the electromagnetic energy stored in the inductor L1 is parasitic on the inductor L1, the DC cut capacitor C1, the filament electrode FLa, the starting capacitor C2, the filament electrode FLb, and the P-type channel transistor Tr2. It flows in the closed circuit of the diode D2, the common reference node a, the primary winding L2a of the saturable current transformer L2 and the inductor L1, and the DC cut capacitor C1 and the start capacitor C2 are further charged.
[0025]
When the electromagnetic energy accumulated in the inductor L1 is consumed, the current due to the charge of the DC cut capacitor C1 and the starting capacitor C2 is changed to the inductor L1, the primary winding L2a of the saturable current transformer L2, the common reference node. a, in a closed circuit of a parasitic diode D1, an output end 5a, a DC power supply 5, an output end 5b, a filament electrode FLb, a starting capacitor C2, a filament electrode FLa, a DC cut capacitor C1 and an inductor L1 of an N-channel transistor Tr1 The electromagnetic energy is accumulated in the inductor L1. At this time, a current flows in the secondary winding L2b of the saturable current transformer L2 from the capacitor C3 in the direction of the resistor R1, the capacitor C3 is charged, and a negative voltage is generated between the common reference node a and the common control node b. Applied. When the negative voltage becomes equal to or lower than the predetermined voltage −Vth, the P-channel transistor Tr2 is turned on.
[0026]
When the P-channel transistor Tr2 is turned on, the current due to the charge of the DC cut capacitor C1 and the starting capacitor C2 is the inductor L1, the primary winding L2a of the saturable current transformer L2, the common reference node a, the P-channel transistor. The source and drain of Tr1, the filament electrode FLb, the starting capacitor C2, the filament electrode FLa, the DC cut capacitor C1, and the inductor L1 flow in a closed circuit, and electromagnetic energy is accumulated in the inductor L1. When the saturable current transformer L2 is saturated, no voltage is output across the secondary winding L2b, and due to the discharge of the capacitor C3, as shown in FIG. 2, between the gate and source of the P-channel transistor Tr2 The voltage (voltage Vab between the common reference node a and the common control node b) increases. When the gate-source voltage of the P-channel transistor Tr2 becomes equal to or higher than the predetermined voltage −Vth, the P-channel transistor Tr2 is turned off.
[0027]
When the P-channel transistor Tr2 is turned off, the regenerative current due to the electromagnetic energy accumulated in the inductor L1 is caused by the inductor L1, the DC cut capacitor C1, the filament electrode FLa, the starting capacitor C2, the filament electrode FLb, and the P-channel transistor Tr2. It flows in a closed circuit of the parasitic diode D2, the common reference node a, the primary winding L2a of the saturable current transformer L2, and the inductor L1. At this time, a current flows from the resistor R1 to the capacitor C3 in the secondary winding L2b of the saturable current transformer L2, the capacitor C3 is charged, and a positive voltage is applied between the common reference node a and the common control node b. As shown in FIG. 2, when the positive voltage is equal to or higher than the predetermined voltage Vth, the N-channel transistor Tr1 is turned on. The inverter circuit 2 is supplied with power from the DC power source 5 and thereafter repeats the above. In several repetitions, a high resonance voltage by the inductor L1 and the starting capacitor C2 is applied between the filament electrodes FLa and FLb of the fluorescent lamp FL, and the fluorescent lamp FL is turned on. When the fluorescent lamp FL is turned on, most of the current flowing through the inductor L1 flows between the filament electrodes FLa and FLb.
[0028]
As described above, depending on the direction of the current flowing through the primary winding L2a of the saturable current transformer L2, a positive voltage is generated between both ends of the secondary winding (output winding) L2b, that is, between the common reference node a and the common control node b. A voltage or a negative voltage is formed, and the N-channel transistor Tr1 and the P-channel transistor Tr2 are alternately turned on / off. By this on / off operation, the inverter circuit 2 outputs a high frequency voltage and energizes the fluorescent lamp FL. That is, the fluorescent lamp FL is energized by the switching output of the inverter circuit 2.
[0029]
Since the saturable current transformer L2 is connected between the inverter circuit 2 and the load circuit 3, the degree of freedom in mounting on the circuit board is improved, and the saturable current transformer L2 is connected to the inverter circuit 2 and the load. It can be disposed on the circuit pattern between the circuits 3 at a position separated from the inductor L1. Thereby, noise due to the leakage magnetic flux of the inductor L1 can be prevented and the circuit board can be miniaturized.
[0030]
Note that the starting circuit 6 first only turns on the N-channel transistor Tr1. That is, the capacitor C4 is charged from the DC power source 5 via the resistor R2 when the N-channel transistor Tr1 is off, and when the N-channel transistor Tr1 is on, the capacitor C4 It is discharged to the inverter circuit 2 side through the series circuit. The P-channel transistor Tr2 is turned off and the N-channel transistor Tr1 is turned on before the voltage across the capacitor C4 makes the trigger diode TD conductive. In the above embodiment, the fluorescent lamp lighting device 4 in which the load circuit 3 is a fluorescent lamp FL or the like has been described. What is necessary is just to operate | move at high frequency by the switching output of the inverter circuit 2, such as a heat ray.
[0031]
Next, a second embodiment of the present invention will be described.
[0032]
FIG. 3 is a side view seen through a globe of a bulb-type discharge lamp showing a second embodiment of the present invention. Note that the same parts as those in FIG. In the figure, 7 is a bulb-type fluorescent lamp, and 8 is a substrate.
[0033]
The bulb-type fluorescent lamp 7 includes a base 8 having a base 9, a lighting circuit 10 shown in FIG. 1 housed in the base 8, a translucent globe 11, a fluorescent lamp FL included in the globe 11, and the like. Yes. The lighting circuit 10 is obtained by removing the fluorescent lamp FL from the fluorescent lamp lighting device 4. And the envelope 12 comprised from the base | substrate 8 and the globe 11 is formed in the external shape approximated to the standard dimension of general light bulbs, such as an incandescent lamp with a rated power of 60 W, for example. The general lighting bulb is defined in JIS C 7501.
[0034]
The base 8 is formed of a heat-resistant synthetic resin such as polybutylene terephthalate (PBT), and the one end has a substantially cylindrical shape that expands, and the other end is attached to the fluorescent lamp FL, and the other end is an Edison type E26 type. The base 9 is covered. The base 9 is fixed by an adhesive or caulking. The base 9 is electrically connected to the lighting circuit 10, and the lighting circuit 10 is electrically connected to the fluorescent lamp FL. That is, the base body 8 has a base 9, supports the fluorescent lamp lighting device 4, and is formed so that the base 9 and the fluorescent lamp lighting device 4 are electrically connected.
[0035]
The globe 11 is made of transparent or light diffusing milky white or the like, and is formed of glass or synthetic resin into a smooth curved surface having substantially the same shape as a glass bulb of a general lighting bulb such as an incandescent bulb. A fitting edge (not shown) that fits inside one end of the base 8 is formed at the edge of the opening. The globe 11 is attached to one end of the base 8 so as to enclose the fluorescent lamp FL.
[0036]
The lighting circuit 10 includes a substantially disc-shaped circuit board (PC board) 13 housed in the base 8 and arranged perpendicular to the longitudinal direction of the fluorescent lamp FL, and an N-channel transistor Tr1 is formed on both surfaces of the circuit board 13. A P-channel transistor Tr2, an inductor L1, a saturable current transformer L2, and other electric components 14 and 15 are mounted. The saturable current transformer L2 is mounted on the circuit board 13 at a position separated from the inductor L1. The lighting circuit 10 operates when power is supplied through the base 9 and outputs high-frequency power to light the fluorescent lamp FL.
[0037]
The fluorescent lamp FL has a plurality of bent bulbs 16, a phosphor (phosphor layer) is formed on the inner surface of the bulb 16, and a rare gas such as argon, mercury, or the like is sealed inside the bulb 16. . A pair of filament electrodes (not shown) are sealed by pinch seals at both ends of the valve 16.
[0038]
As described above, the saturable current transformer L2 is connected between the inverter circuit 2 and the load circuit 3 in FIG. 1 and mounted on the circuit board 13 at a position spaced apart from the inductor L1, so that the inductor L1 Malfunctions and characteristic changes due to leakage flux are prevented. Further, since the saturable current transformer L2 may be disposed on the circuit pattern between the inverter circuit 2 and the load circuit 3, the degree of design freedom for mounting the saturable current transformer L2 on the circuit board 13 is improved. The circuit board can be miniaturized.
[0039]
The bulb-type fluorescent lamp may be one in which the fluorescent lamp FL is exposed.
[0040]
【The invention's effect】
According to the present invention, both ends of the output winding of the saturable current transformer are connected to the common reference node and the common control node of the complementary transistors, respectively. The switching means is switched to output a high frequency and can operate the load circuit at the high frequency. In addition, the saturable current transformer has only to connect both ends of the output winding to the common reference node and common control node of the complementary transistor, so that the circuit connection pattern is simplified and the circuit board surface side of the inductance element is the same. Even if it is placed, it becomes easy to place it on a part of the circuit board that is not affected by the leakage magnetic flux of the inductance element, the design flexibility of the circuit board is improved and the circuit board can be miniaturized, and the miniaturized light bulb A shaped fluorescent lamp can be provided.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of an inverter device or a fluorescent lamp lighting device according to a first embodiment of the present invention.
FIG. 2 is also an explanatory diagram showing a voltage and a drain current between a common reference node and a common control node.
FIG. 3 is a side view seen through a globe of a bulb-type discharge lamp showing a second embodiment of the present invention.
FIG. 4 is a circuit diagram of a conventional fluorescent lamp lighting device.
[Explanation of symbols]
L2: Saturable current transformer 1 ... Inverter device 2 ... Inverter circuit 3 as switching means ... Load circuit 4 ... Fluorescent lamp lighting device 7 ... Bulb-type fluorescent lamp 8 ... Base

Claims (1)

Switching means having a complementary transistor connected in series between output terminals of a DC power source, a common reference node in which the reference nodes of the transistor are connected, and a common control node in which the control nodes are connected, and the switching means A fluorescent lamp lighting device having a saturable current transformer that is connected so that a switching output of each of the output windings flows and whose both ends of the output winding are respectively connected to a common reference node and a common control node ;
An inductance element for limiting the switching output of the switching means, a fluorescent lamp having a pair of electrodes connected via an inductance element between the switching outputs of the switching means, and an inductance element connected in parallel between the electrodes of the fluorescent lamp, A load circuit consisting of a starting capacitor forming a series resonant circuit and energized by the switching output of the switching means;
A circuit board on which circuit components of a fluorescent lamp lighting device and a load circuit are mounted;
A base body having a base, supporting the circuit board, and formed so that the base and the fluorescent lamp lighting device of the circuit board are electrically connected;
A bulb-type fluorescent lamp characterized in that the inductance element and the saturable current transformer are arranged on the same surface side of the circuit board.

Images