JP2000077195A - Compact self-ballasted fluorescent lamp and luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact self-ballasted fluorescent lamp and a luminaire capable of stopping oscillation operation of an inverter circuit by a simple constitution at a terminal period of a lifetime of the fluorescent lamp. SOLUTION: A fluorescent lamp 2 in a compact self-ballasted fluorescent lamp 1 is provided with a light emitting portion 2c bent into a U shape. A screw-in base 5 electrically connectable to a commercial AC power source Vs is fitted at one end 3a of a base body 3, in the meanwhile, the fluorescent lamp 2 is fixed at the other end 3b via a resin or the like. A circuit board 6 supported by the base body 3 is housed inside the base body 3. A high frequency lighting device 4, on which an inverter 7 having a switch element Q1 is packaged, is contained inside the circuit board 6. In the circuit board 6, one of the switch elements Q1 constituting inverter 7 is disposed at one surface thereof (at the lower surface thereof), and further, a heat generating part R1 is disposed at the other surface thereof (at the upper surface thereof) provided with the switch element Q1. At the terminal period of a lifetime of the fluorescent lamp 2, the switch element Q1 is immediately heat-broken due to its own heat generation and the heat effect of the heat generating part R1, thereby stopping the inverter 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a compact fluorescent lamp and a lighting apparatus.

[0002]

2. Description of the Related Art In a bulb-type fluorescent lamp using a high-frequency lighting circuit, if the fluorescent lamp is kept operating at the end of its life, the bulb temperature in the vicinity of the electrode will rise excessively, causing damage to peripheral parts. There's a problem. For this reason, generally, a fuse is inserted in the power supply input section, and when the input current increases at the end of the life of the fluorescent lamp, the fuse is cut off to prevent the parts from being damaged. For example, JP
As shown in FIG. 6, a high-frequency lighting device for a bulb-type fluorescent lamp disclosed in Japanese Patent Application Publication No. 162700 discloses a smoothing capacitor 22 for rectifying and then smoothing a commercial AC power supply Vs with a rectifier 21 and a MOS field effect transistor 24. A thermal fuse 23 is interposed between them. As shown in FIG. 7, the thermal fuse 23 is sandwiched between a heat sink 24a of the MOS field effect transistor 24 and a heat sink 25a of the MOS field effect transistor 25, and both the MOS field effect transistors 24, 25, and is disposed on the circuit board 26. And the fluorescent lamp 27
When the lamp current is at the end of life or when the operation of the high frequency lighting device 20 becomes abnormal and the lamp current increases, the circuit components of the high frequency lighting device 20 generate abnormal heat. In particular, MOS type field effect transistors 24 and 2
Since a large lamp current flows through 5, the heat generation becomes extremely large. Thus, a large amount of heat is released to the heat radiating plates 24a and 25a, and as a result, the thermal fuse 23 is blown in a short time. When the thermal fuse 23 is blown, the operation of the inverter circuit 28 is stopped, and the fluorescent lamp 27 is not energized.

[0003]

The above-mentioned conventional bulb-type fluorescent lamp is composed of MOS field-effect transistors 24,2.
5 is directly received by the thermal fuse 23, so that the operation of the inverter circuit 28 can be stopped in a short time at the end of the life of the fluorescent lamp 27. However, since the above-described conventional bulb-type fluorescent lamp includes the thermal fuse 23, the number of components is increased, and the thermal fuse 23 is disposed on the circuit board 26 so as to be sandwiched between the radiating plates 24a and 25a. Requires a long time, resulting in an increase in product cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a light bulb-shaped fluorescent lamp and a lighting apparatus which can stop the oscillation operation of an inverter circuit with a simple configuration mainly at the end of the life of the fluorescent lamp. The purpose is to:

[0005]

According to a first aspect of the present invention, there is provided a bulb-type fluorescent lamp comprising: a base having a base electrically connectable to a commercial AC power supply; a fluorescent lamp mounted on the base; A circuit board supported by a base, and an inverter that converts a commercial AC power supplied through the base into DC and outputs high-frequency power to the fluorescent lamp by oscillation of a switch element is mounted on the circuit board; A high-frequency lighting device in which the switch element is disposed on one surface side of the circuit board and a heat-generating component is disposed on the other surface side of the portion where the switch element is disposed.

In the present invention and each of the following inventions, the definitions and technical meanings of terms are as follows unless otherwise specified.

[0007] A fluorescent lamp is a lamp having a bent shape such as a U-shape or a saddle shape, and the tube diameter, length, electric power, type and the like are not limited.

[0008] The switch element is a field effect transistor,
Any number of bipolar transistors, such as bipolar transistors, may be used as long as they perform an on / off operation to constitute an inverter.

The portion where the switch element is provided is a place where the switch element provided on one side of the circuit board occupies the circuit board, that is, the switch element is placed on the circuit board in a direction perpendicular to the circuit board. This is the range projected when the projection is performed, but if the heat-generating component gives a thermal effect to the switch element, the vicinity thereof is allowed.

The heat-generating component is a component whose heat value increases with an increase in lamp power and constitutes a part of a circuit component of the high-frequency lighting device. Therefore, when there are a plurality of switch elements such as a half bridge type inverter, one of them can be used as a heat-generating component.

It is sufficient that the switch element is disposed on the circuit board so as to be thermally affected by the heat-generating component when the heat-generating component abnormally generates heat. It is not necessary to arrange the switch element closely or close to the circuit board. Absent.

The bulb-type fluorescent lamp is supplied with power from a commercial AC power supply via a base. The switch element of the inverter oscillates and outputs high-frequency power to the fluorescent lamp, and the fluorescent lamp is turned on. When the fluorescent lamp reaches the end of its life or the inverter operates abnormally, the input current increases and the heat generation of the heat-generating component increases, and the heat generation of the switch element also increases. The switch element is thermally destroyed in a short time due to the heat generated by the heat-generating component in addition to its own heat generation. as a result,
The inverter stops oscillating and the fluorescent lamp goes off.

The high-frequency lighting device is configured such that a heat-generating component is provided on the other surface of the portion of the switch device provided on one surface of the circuit board. Easy to receive. As a result, when the fluorescent lamp reaches the end of its life or when the inverter operates abnormally, the switch element can be immediately thermally destroyed to stop the inverter.

According to a second aspect of the present invention, there is provided a bulb-type fluorescent lamp according to the first aspect, wherein the heat-generating component is an inductor element or a series-connected inductor element connected between a rectifier circuit and a switch element. It is a resistance element.

The inductor element or the resistance element is an element for preventing an inrush current, and generates a large amount of heat at the end of life as the input current increases.

Since the heat generating component generates a large amount of heat as the input current increases due to the end of the life of the fluorescent lamp, the abnormal operation of the inverter, or the like, the switch element can be heated and immediately destroyed by heat.

According to a third aspect of the present invention, there is provided the bulb-type fluorescent lamp according to the first or second aspect, wherein one side of the circuit board on which the switch element is provided faces the fluorescent lamp. I have.

Since the switch element is disposed to face the fluorescent lamp, it is easily damaged by heat from the fluorescent lamp.

According to a fourth aspect of the present invention, there is provided the bulb-type fluorescent lamp according to any one of the first to third aspects, wherein the circuit board has a thickness of 0.5 to 1.0 mm.

If the thickness of the circuit board is less than 0.5 mm, the mechanical strength of the circuit board is small and it is not practical, and if the circuit board has components mounted on both sides, the withstand voltage characteristics between the two sides deteriorate. Would. Further, when the thickness of the circuit board exceeds 1.0 mm, heat from the heat-generating components is not transmitted well to the switch element via the circuit board, and the height of the high-frequency lighting device increases, so that the high-frequency In order to accommodate the lighting device, it is necessary to make the base large, and as a result, the bulb-type fluorescent lamp becomes large. Therefore,
The thickness of the circuit board is 0.5 to 1.0 mm.

Since the thickness of the circuit board is 0.5 to 1.0 mm, it is possible to effectively perform a heat effect, to reduce the height of the high-frequency lighting device, and to make the compact fluorescent lamp compact. .

According to a fifth aspect of the present invention, there is provided a lighting apparatus comprising: the light bulb-shaped fluorescent lamp according to any one of the first to fourth aspects; and a lighting apparatus main body accommodating the light bulb-shaped fluorescent lamp.

A lighting fixture having the functions and effects of the first to fourth aspects can be provided.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cutaway sectional view of a light bulb-shaped fluorescent lamp showing a first embodiment of the present invention, and FIG. 2 is a circuit diagram of a lighting device of the light bulb-shaped fluorescent lamp.

The bulb-type fluorescent lamp 1 shown in FIG. 1 comprises a fluorescent lamp 2, a base 3, a lighting device 4, and the like. The fluorescent lamp 2 has a light emitting portion 2c bent in a U-shape, an inert gas such as an argon gas is sealed therein, and electrodes (not shown) are sealed at both ends 2a and 2b. The base 3 is made of a heat-resistant synthetic resin such as a PBT resin, and a screw-type base 5 that can be electrically connected to a commercial AC power supply is attached to one end 3a, and the fluorescent lamp 2 is made of a resin or the like at the other end 3b. It is fixed by using. A high-frequency lighting device 4 as a lighting device having a circuit board 6 supported by the base 3 and an inverter 7 having a switch element Q1 mounted on the circuit board 6 is accommodated inside the base 3. Have been. The circuit board 6 has a thickness of 0.5 to 1.0 mm
One of the switch elements Q1 constituting the inverter 7 is disposed on one surface side (lower surface side), and heat is generated on the other surface side (upper surface side) where the switch element Q1 is disposed. A resistance element R1 as a component is provided. As a result of disposing the switching element Q1 on the lower surface side of the circuit board 6, the switching element Q1 faces the fluorescent lamp 2 and is easily affected by the heat action from the fluorescent lamp 2. The high-frequency lighting device 4 is electrically connected to the base 5 and the fluorescent lamp 2 by a lead wire (not shown). In the inverter 7,
A power supply obtained by converting a commercial AC power supply supplied through the base 5 into a DC power is input. The high frequency power is output to the fluorescent lamp 2 by the oscillation of the switch element Q1 to turn on the fluorescent lamp 2, and the operation is stopped by the destruction of the switch element Q1. Note that the base 5 may be a plug-in type.

Next, the high-frequency lighting device 4 shown in FIG. 2 will be described.

In the high-frequency lighting device 4, a capacitor C1 is connected to a commercial AC power supply Vs via a fuse F1, and an input terminal of a full-wave rectifier Rec1 is connected via an inductor L1. The capacitor C1 and the inductor L1 form a noise filter. Full-wave rectifier R
A smoothing capacitor C2 is connected to an output terminal of ec1 via a resistor R1 to form a DC power supply. Resistance R1
Is an element for preventing inrush current, and the resistor R1 may be an inductor. The half-bridge type inverter circuit 7 of the instant start system is connected to the smoothing capacitor C2.

The inverter circuit 7 includes a smoothing capacitor C
A series circuit of a MOS-type N-channel field-effect transistor Q1 and a MOS-type P-channel field-effect transistor Q2, which are switch elements, is connected to both ends of the switch 2. The filaments 2d and 2 of the fluorescent lamp 2 are connected between the drain and the source of the field effect transistor Q2 via a ballast choke L2 and a DC cut capacitor C3.
e is connected to one end, and a preheating capacitor C4 is connected between one end of the filament 2d and the other end of the filament 2e.

Further, a resistor R1 and a smoothing capacitor C
A starting resistor R2 constituting a starting circuit 8 is connected between the connection point a of the first switching element 2 and the gate of the field effect transistor Q1 and the gate of the field effect transistor Q2, and the gate of the field effect transistor Q1 and the field effect transistor A series circuit of a capacitor C5 and a capacitor C6 is connected between a gate of Q2 and a connection point b of the field effect transistor Q1 and the field effect transistor Q2,
A series circuit of a Zener diode ZD1 and a Zener diode ZD2 for protecting the gates of the field effect transistor Q1 and the field effect transistor Q2 is connected in parallel with the series circuit of the capacitor C5 and the capacitor C6 of the control circuit 9 as a control means. Have been. A secondary winding L3 is magnetically connected to the ballast choke L2, and an inductor L4 is connected to the secondary winding L3.
And a resonance circuit 10 of the capacitor C6. Further, the resistor R3 of the starting circuit 8 is connected in parallel with the series circuit of the capacitor C5 and the inductor L4. Further, a parallel circuit of a resistor R4 of the starting circuit 8 and a switching improvement capacitor C7 is connected between the drain and the source of the field effect transistor Q2.

The commercial AC power supply Vs of the high-frequency lighting device 4
Each component except the fluorescent lamp 2 is mounted on the circuit board 6. The N-channel field-effect transistor Q1 is mounted on one side of the circuit board 6, the inrush current preventing resistor R1 is mounted on the other side of the portion where the N-channel field-effect transistor Q1 is mounted, and the other side is mounted on the other side. Parts are mounted.

The fluorescent lamp 2 has a filament 2d.
Is one-sided preheating, but a lamp of a two-sided preheating method may be used. Further, the switch element mounted on one side of the circuit board 6 may be a P-channel field effect transistor Q2.

Next, the operation of the first embodiment will be described.

When the high frequency lighting device 4 is powered on,
The AC voltage of the commercial AC power supply Vs is full-wave rectified by the full-wave rectifier Rec1, and is smoothed by the smoothing capacitor C2. And
An N-channel field effect transistor Q1 is connected via a resistor R2.
Is applied to the gate of the transistor Q1, and the field effect transistor Q1
Turns on, and the fluorescent lamp 2 passes through the ballast choke L2.
Is applied with a voltage. Then, a voltage is induced in the secondary winding L3 of the ballast choke L2, and the inductor L4 and the capacitor C6 of the control circuit 9 undergo natural resonance, and a voltage is alternately applied to the gates of the field effect transistor Q1 and the field effect transistor Q2. Field effect transistor Q1
And the field effect transistor Q2 is turned on and off alternately, and the fluorescent lamp 2 is turned on. When the fluorescent lamp 2 is normally lit, the field effect transistors Q1 and Q2 and the resistor R2 generate heat, but this heat is not enough to cause the field effect transistors Q1 and Q2 to be thermally destroyed.

When the fluorescent lamp 2 reaches the end of its life and undergoes a half-wave discharge, the lamp voltage rises and the N-channel field-effect transistors Q1 and P1 of the inverter circuit 7 in which a half bridge is formed by two asymmetrical direct currents caused by the half-wave discharge. The current flows to the channel field effect transistor Q2. The drain current flowing through the N-channel field-effect transistor Q1 and the P-channel field-effect transistor Q2 and the N-channel field-effect transistors Q1 and P2
The ON / OFF timing of the channel field effect transistor Q2 is shifted, and stress is applied to the N channel field effect transistor Q1 and the P channel field effect transistor Q2 to generate heat. As the life of the fluorescent lamp 2 progresses, the asymmetric current increases, and the heat generated by the N-channel field-effect transistor Q1 and the P-channel field-effect transistor Q2 increases. On the other hand, the input current flowing through the resistor R1 also increases with the progress of the life of the fluorescent lamp 2, and the resistance R1 increases.
The heat generation of No. 1 increases. The N-channel field effect transistor Q1 is finally thermally destroyed by the heat generated by its own heat and the heat generated by the resistor R1. As a result, the inverter circuit 7 stops oscillating, and the fluorescent lamp 2 is turned off.

Since the resistor R1 is provided on the other side (upper side) of the portion of the N-channel field effect transistor Q1 provided on one side (lower side) of the circuit board 6, the N-channel field effect transistor is provided. Q1 is susceptible to thermal action from resistor R1. In addition, the N-channel field effect transistor Q
Since one surface side (lower surface side) of the circuit board 6 provided with 1 is opposed to the fluorescent lamp 2, the N-channel field effect transistor Q1 is also subjected to the action of heat generated by the fluorescent lamp 2. Therefore, when the fluorescent lamp 2 performs a half-wave discharge at the end of its life, the N-channel field effect transistor Q1 is immediately thermally destroyed and the fluorescent lamp 2 is turned off, so that the bulb-type fluorescent lamp 1 can be replaced immediately. In addition, since the special assembly of the thermal fuse 23 shown in FIG. 7 is not performed, the bulb-type fluorescent lamp 1 can be inexpensive.

FIG. 3 is a partially cutaway sectional view of a light bulb-shaped fluorescent lamp showing a second embodiment of the present invention. The same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The bulb-type fluorescent lamp 11 shown in FIG. 3 includes a fluorescent lamp 12, a base 3, a lighting device 4, and a globe 1.
3 and the like. The fluorescent lamp 12 is bent in a saddle shape and has lamp characteristics such as 23 W and 25 W.
The base 3 is formed of a heat-resistant synthetic resin such as a PBT resin,
A screw-type base 5 electrically connected to a commercial AC power supply Vs is attached to one end 3a, and a fluorescent lamp 12 is attached to the other end 3b using a resin or the like. Fluorescent lamp 1
2 is covered with a translucent globe 13 attached to the other end 3b of the base 3. The base 3 has a circuit board 6 supported by the base 3, and the components of the high-frequency lighting device 4 shown in FIG. 2 are mounted on the circuit board 6. The high-frequency lighting device 4 is electrically connected to the base 5 and the fluorescent lamp 12 by lead wires (not shown). The inverter 7 is supplied with a power obtained by converting a commercial AC power supply Vs supplied through the base 5 into a DC power. Then, the high frequency power is output to the fluorescent lamp 12 by the oscillation of the field effect transistors Q1 and Q2 as the switch elements to turn on the fluorescent lamp 12, and the operation is stopped by the destruction of the field effect transistor Q1. The base 3 and the globe 13 may have holes for ventilation.

When the fluorescent lamp 12 has a half-wave discharge at the end of its life, the N-channel field effect transistor Q1 is immediately destroyed by heat and the fluorescent lamp 12 is turned off. Therefore, the bulb-type fluorescent lamp 11 can be replaced immediately. Further, since the fluorescent lamp 12 is covered with the globe 13, the appearance and the commerciality of the bulb-type fluorescent lamp 11 are improved.

Next, a third embodiment of the present invention will be described.

FIG. 4 is a partially cutaway sectional view of a lighting fixture showing a third embodiment of the present invention.

The lighting fixture 14 shown in FIG. 4 is a portal lamp, and the bulb-type fluorescent lamp 1 shown in FIG.

When the fluorescent lamp 2 reaches the end of its life, it is possible to provide a lighting device 14 in which the bulb-type fluorescent lamp 1 is turned off.

Next, a fourth embodiment of the present invention will be described.

FIG. 5 is a partially cutaway sectional view of a lighting fixture showing a fourth embodiment of the present invention.

The lighting fixture 16 shown in FIG. 5 is a downlight buried in a ceiling or the like. The light bulb-shaped fluorescent lamp 11 shown in FIG.

When the fluorescent lamp 12 reaches the end of its life, it is possible to provide a lighting fixture 16 which turns off the lamp.

In the above-described embodiment, the portal lamp and the downlight have been described as the lighting fixtures. However, the lighting fixture is not limited to these, and any lighting fixture that accommodates the bulb-type fluorescent lamp of the present invention in the lighting fixture body may be used.

[0049]

According to the first aspect of the present invention, since the heat-generating component is provided on the other surface of the portion of the switch device provided on one surface of the circuit board, the switch device is not affected by the heat-generating component. When the fluorescent lamp is at the end of its life or the inverter operates abnormally, the switching element can be immediately destroyed by heat and the inverter can be stopped.

According to the second aspect of the present invention, since the heat generating component generates a large amount of heat when the input current increases, the switch element can be immediately thermally destroyed at the end of the life of the fluorescent lamp.

According to the third aspect of the present invention, since the switch element is disposed to face the fluorescent lamp, the switch element is easily damaged by heat from the fluorescent lamp.

According to the fourth aspect of the present invention, since the thickness of the circuit board is 0.5 to 1.0 mm, it is possible to effectively perform the heat action and to reduce the height of the high-frequency lighting device. As a result, the compact fluorescent lamp can be made smaller.

According to the fifth aspect of the present invention, it is possible to provide a lighting device in which the bulb-type fluorescent lamp is turned off when the fluorescent lamp reaches the end of its life.

[Brief description of the drawings]

FIG. 1 is a partially cutaway cross-sectional view of a light bulb-shaped fluorescent lamp showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a high-frequency lighting device.

FIG. 3 is a partially cutaway sectional view of a light bulb-shaped fluorescent lamp showing a second embodiment of the present invention.

FIG. 4 is a partially cutaway sectional view of a lighting fixture showing a third embodiment of the present invention.

FIG. 5 is a partially cutaway cross-sectional view of a lighting fixture showing a fourth embodiment of the present invention.

FIG. 6 is a circuit diagram of a conventional high-frequency lighting device.

FIG. 7 is a state diagram showing mounting of a thermal fuse on a circuit board.

[Explanation of symbols]

Q1 N-channel field-effect transistor as switch element Q2 P-channel field-effect transistor as switch element R1 Resistance as heat-generating component 1,11 Light-bulb-shaped fluorescent lamp 2,12 Fluorescent lamp 3 Base 4 High-frequency lighting device 5 Base 6 Circuit board 7 Inverter 14 16 Lighting equipment 15 17… Lighting equipment body

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3K014 AA04 DA08 3K072 AA02 AA06 BA03 BB01 BC01 BC03 DB03 DC02 EA01 GA03 GB01 GB12 GC02

Claims (5)

[Claims] 1. A base having a base electrically connectable to a commercial AC power supply; a fluorescent lamp attached to the base; and a circuit board supported by the base, the circuit board including the base. An inverter for converting the commercial AC power supplied through the DC power supply to high frequency power to the fluorescent lamp by oscillating the switch element is mounted, and the switch element is disposed on one surface side of the circuit board, and the switch element is A high-frequency lighting device in which a heat-generating component is disposed on the other surface side of the disposed portion; 2. The light bulb-shaped fluorescent lamp according to claim 1, wherein the heat generating component is an inductor element or a resistance element connected in series between the rectifier circuit and the switch element. 3. The light bulb-shaped fluorescent lamp according to claim 1, wherein one side of the circuit board on which the switch element is provided is opposed to the fluorescent lamp. 4. The bulb-type fluorescent lamp according to claim 1, wherein the circuit board has a thickness of 0.5 to 1.0 mm. 5. A lighting fixture comprising: the bulb-shaped fluorescent lamp according to claim 1; and a lighting fixture main body that houses the bulb-shaped fluorescent lamp.