JPH07274521A - Electric power unit, electric discharge lamp lighting device and illuminating device - Google Patents

Abstract

PURPOSE:To provide an electric discharge lamp lighting device uniformly distributing power to a plurality of loads. CONSTITUTION:Voltage of a commercial AC power supply E, removing a noise in a filter circuit 1, is full-wave rectified by a full-wave rectifier 2 and converted into a high frequency by an inverter circuit 3, to light fluorescent lamps FL1, FL2 at a high frequency. In the fluorescent lamp FL1, a resonance circuit 4 of a capacitor C11 of small capacity, coil L1 and a capacitor C6 resonates by amplitude between voltage of a capacitor C3 of large capacity and voltage of a capacitor C9, to generate high frequency voltage in the capacitor C11 and to generate voltage in a diode D11 averaged, so as to form an input current in a sinusoidal wave curve, and a power factor is improved to reduce a higher harmonic wave. An operation is performed similarly relating to a diode D12. Dispersion of resonance circuits 4, 5 is eliminated to supply a respectively equal current to the fluorescent lamps FL1, FL2, and brightness therebetween is uniformly generated, so as to eliminate dispersion of the brightness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, a discharge lamp lighting device and a lighting device in which a plurality of loads are connected in parallel to an inverter circuit.

[0002]

2. Description of the Related Art Conventionally, as a discharge lamp lighting device of this type,
For example, the configuration shown in FIG. 8 is known.

As shown in FIG. 8, a commercial AC power source E is connected to an input terminal of a full-wave rectifier 2 such as a diode bridge via a filter circuit 1 composed of a capacitor C1, a transformer Tr1 and a capacitor C2. A capacitor C3 is connected between the output terminals of the full-wave rectifier 2, and a series circuit of a diode D1 and a capacitor C4 is connected in parallel with the capacitor C3.

A half-bridge type inverter circuit 3 composed of a field effect transistor Q1 and a field effect transistor Q2 is connected to the capacitor C4 via a diode D2.

Then, the diode D1 and the capacitor C4
A capacitor for starting between the coil L1, the filament FL1a and the filament FL1b between the connection point of the field effect transistor Q1 and the connection point of the field effect transistor Q2.
Fluorescent lamp FL1 as a discharge lamp connected with C5 and series circuit of capacitor C6, coil L2, filament
Starting capacitor C7 between FL2a and filament FL2b
Is connected to a series circuit of a fluorescent lamp FL2 as a discharge lamp connected to and a capacitor C8.

Further, a capacitor C9 is connected between both terminals of the field effect transistor Q1 and the field effect transistor Q2.

Then, the voltage of the commercial AC power source E is noise-removed by the filter circuit 1, full-wave rectified by the full-wave rectifier 2 and converted into a high frequency by the inverter circuit 3, and the fluorescent lamp FL.
1 and FL2 are lit at high frequency.

Further, each of the fluorescent lamps FL1 and FL2 has a resonance circuit of a coil L1 and a capacitor C6, or a coil L2 and a capacitor C8, respectively, and a high frequency is superimposed on the full-wave rectified pulsating current to obtain a power factor. Has improved.

[0009]

However, in the case of the above-mentioned conventional discharge lamp lighting device, the resonance circuit of the condenser C4, the coil L1 and the condenser C6 of the fluorescent lamp FL1, and the condenser C4, the coil L2 and the condenser of the fluorescent lamp FL2.
If there is variation in the resonance circuit of C8, there is a problem that variation in brightness of the fluorescent lamps FL1 and FL2 may occur.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a power supply device, a discharge lamp lighting device, and a lighting device in which electric power is evenly distributed to a plurality of loads.

[0011]

According to a first aspect of the present invention, there is provided a power supply device in which a load is connected in parallel to an inverter circuit that oscillates and outputs a switching element. Resonant circuits each having a small-capacity capacitor that is electrically discharged are provided for each of the loads.

According to a second aspect of the present invention, there is provided the power source apparatus according to the first aspect, further comprising load attachment / detachment detecting means for detecting the connection state of the load based on the voltage of a capacitor having a small capacity.

According to a third aspect of the present invention, in the power source apparatus according to the second aspect, the power supply device includes a large-capacity capacitor connected to the input side of the inverter circuit and having a larger capacity than the capacitor of the resonance circuit, and the load attachment / detachment detection means. And a capacitance varying means for varying the capacitance of the large-capacity capacitor based on the detected connection state of the load.

In the discharge lamp lighting device according to the fourth aspect, the load of the power supply device according to the first or second aspect is the discharge lamp.

A discharge lamp lighting device according to a fifth aspect of the present invention is the discharge lamp lighting device according to the fourth aspect including a fixture main body.

[0016]

In the power supply device according to the present invention, since the resonance circuit having a small capacity capacitor that substantially discharges when the switching element of the inverter circuit is turned on and off is provided for each load, the resonance circuit for each load is provided. Since it can be made uniform, it is possible to eliminate variations in each load.

According to a second aspect of the present invention, in the power source apparatus according to the first aspect, the load attachment / detachment detecting means detects the connection state of the load based on the voltage of the small-capacity capacitor.
The load mounting state can be detected with a simple configuration.

According to a third aspect of the power source device of the present invention, in the power source device of the second aspect, the capacitance of the large-capacity capacitor is varied by the capacitance varying means in accordance with the amount of the load detected by the load attachment / detachment detecting means. The capacity depends on the quantity, and the efficiency is improved.

In the discharge lamp lighting device according to the fourth aspect, since the load of the power supply device according to the first or second aspect is the discharge lamp, it is possible to suppress variations in brightness of the discharge lamp.

In the discharge lamp lighting device according to the fifth aspect, since the discharge lamp lighting device according to the fourth aspect is provided with the instrument body, it is possible to suppress variations in the brightness of the discharge lamp.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the illumination device of the present invention will be described below with reference to the drawings. It should be noted that parts corresponding to the discharge lamp lighting device shown in FIG.

In FIG. 2, 11 is a main body of the appliance, and a pair of lamp sockets 12 are attached to both ends of the main body 11 of the appliance, and load lamps, fluorescent lamps FL1 and FL2 as discharge lamps are attached to the lamp socket 12, and Fluorescent lamp FL
Reflective surface 13 is formed between 1 and FL2 and in the opposite portion,
A discharge lamp lighting circuit 14 is housed inside the fixture body 11.

As shown in FIG. 1, the discharge lamp lighting circuit 14 includes a full-wave rectifier 2 such as a diode bridge connected to a commercial AC power source E via a filter circuit 1 including a capacitor C1, a transformer Tr1 and a capacitor C2. The input terminal of is connected. A large-capacity capacitor C3 having a relatively large capacity is connected between the output terminals of the full-wave rectifier 2, and a diode D1 is connected in parallel with the capacitor C3.
Series circuit of 1 and small capacitor C11, and
A series circuit of a diode D12 and a small capacity capacitor C12 is connected.

The capacitor C11 has a diode D13
And the diode D14 is connected to the capacitor C12, and the field effect transistor Q1 and the field effect transistor Q1 as switching elements are connected between the connection point of these diodes D13 and D14 and the connection point of the capacitors C11 and C12. A half-bridge type inverter circuit 3 composed of Q2 is connected.

Then, the diode D11 and the capacitor
Between the connection point of C11 and the connection point of field effect transistor Q1 and field effect transistor Q2, a fluorescent lamp FL1 and a capacitor in which a starting capacitor C5 is connected between coil L1, filament FL1a and filament FL1b.
A series circuit of C6 is connected, and between the connection point of diode D12 and capacitor C12 and the connection point of field effect transistor Q1 and field effect transistor Q2, coil L2,
A series circuit of a fluorescent lamp FL2 and a capacitor C8, in which a starting capacitor C7 is connected, is connected between the filament FL2a and the filament FL2b.

The resonant circuit 4 is formed by the capacitor C11, the coil L1 and the capacitor C6, and the resonant circuit 5 is formed by the capacitor C12, the coil L2 and the capacitor C8.

Further, a capacitor C9 is connected between both terminals of the field effect transistor Q1 and the field effect transistor Q2.

Next, the operation of the embodiment shown in FIG. 1 will be described.

First, the voltage of the commercial AC power source E is noise-removed by the filter circuit 1, full-wave rectified by the full-wave rectifier 2 and converted into a high frequency by the inverter circuit 3, and the fluorescent lamp FL1.
, FL2 is lit at high frequency.

The fluorescent lamp FL1 is composed of a capacitor C11,
Resonating in the resonance circuit 4 of the coil L1 and the capacitor C6, the voltage between the voltage of the capacitor C9 shown in FIG. 3A and the voltage of the capacitor C3 shown in FIG.
By generating the high frequency voltage shown in FIG. 3 (c) in C11 and causing the current shown in FIG. 3 (d) in the diode D11 and averaging it by the filter circuit 1, the input current becomes a sinusoidal curve, Improve power factor and reduce harmonics.

On the other hand, similarly, the fluorescent lamp FL2 resonates in the resonance circuit 5 of the capacitor C12, the coil L2 and the capacitor C8, and the voltage of the capacitor C3 shown in FIG.
The voltage of the capacitor C9 shown in (b) is oscillated to generate the high frequency voltage shown in FIG. 3 (c) in the capacitor C12 and generate the current shown in FIG. 3 (d) in the diode D12. By averaging with
By making the input current a sinusoidal curve as shown in (e), the power factor is improved and harmonics are reduced.

In this way, variations in the resonance circuit 4 and the resonance circuit 5 are eliminated, and equal currents are supplied to the fluorescent lamp FL1 and the fluorescent lamp FL2, respectively.
Make the brightness between FL1 and fluorescent lamp FL2 uniform to eliminate variations in brightness.

Next, another embodiment will be described with reference to FIG.

In the embodiment shown in FIG. 4, another load is added to the fluorescent lamps FL1 and FL2 of the embodiment shown in FIG.
A fluorescent lamp FL3 as a discharge lamp is connected in parallel.

That is, in addition to the embodiment shown in FIG. 1, a series circuit of a diode D15 and a small capacity capacitor C13 is connected in parallel with the capacitor C3,
A diode D16 is connected to the diode D16, and between the connection point of the diode D16 and the capacitor C13 and the connection point of the field effect transistor Q1 and the field effect transistor Q2, a capacitor for starting between the coil L11, the filament FL3a and the filament FL3b. The series circuit of the fluorescent lamp FL3 to which C14 is connected and the capacitor C15 is connected,
The resonance circuit 6 is formed by C13, the coil L11 and the capacitor C15.

The embodiment shown in FIG. 4 also operates similarly to the embodiment shown in FIG. 1, and the fluorescent lamps FL1, FL2,
It is a uniform brightness of FL3.

Another embodiment will be described with reference to FIG.

The embodiment shown in FIG. 5 is the attachment / detachment detection means as load attachment / detachment detecting means for detecting attachment / detachment of the fluorescent lamps FL1, FL2 by detecting the voltage on the capacitors C11 and C12 of the embodiment shown in FIG. A circuit 21 is connected, a control circuit 22 is connected to the attachment / detachment detection circuit 21, an OSC 23 is connected to the control circuit 22, and the oscillation of the field effect transistors Q1 and Q2 is controlled by the OSC 23.

That is, when the fluorescent lamp FL1 and the fluorescent lamp FL2 are respectively connected, the resonance circuit 4 and the resonance circuit 5 are formed, respectively.
As shown in (a), a voltage on which a high frequency is superimposed is detected. On the other hand, fluorescent lamp FL1 or fluorescent lamp
When FL2 is removed, the resonance circuit 4 or the resonance circuit 5 is not formed, so that a DC voltage of 2 ^1/2 of the input voltage is detected as shown in FIG. 6B.

Therefore, the attachment / detachment of the fluorescent lamp FL1 or the fluorescent lamp FL2 can be detected.

Fluorescent lamp FL1 and fluorescent lamp
If FL2 attachment / detachment is detected, the number of attachments is 2 to 1,
OSC to stop when 1 to 0, 0 to 1 and start sequence when 1 to 2
Controlled by 23.

As another pattern, the number of mounted pieces is 2
It may be controlled by the OSC 23 so as to thin out the light from one line, stop the light from one line to zero, and start the sequence from zero line to one line and one to two lines.

As described above, the field effect transistors Q1 and
You can reduce stress such as Q2.

Further, another embodiment will be described with reference to FIG.

The embodiment shown in FIG. 7 differs from the embodiment shown in FIG. 1 in that capacitor C3 is connected in parallel with capacitor C3.
Similarly, a series circuit of a large-capacity capacitor C21 having a relatively large capacity and a switching device 25 as a capacitance varying means is connected.
, D22, D23, D24 and a transistor Q11 as a control means, the transistor Q11 is on / off controlled by the attachment / detachment detection circuit 21 of the fluorescent lamps FL1, FL2.

When any of the fluorescent lamps FL1 and FL2 is lit, the capacity is increased in a state where the transistor Q11 is turned on and the capacitor C21 is connected in parallel with the capacitor C3, and either fluorescent light is emitted. Lamp FL1, FL2
When it is detected that is removed, the transistor Q11 is turned off and the capacitor C21 is opened to reduce the capacitance.

Thus, according to the number of the fluorescent lamps FL1 and FL2 mounted, the capacitors C3 and C21
By changing the combined capacitance of, the period in which the input current is stopped is prevented, and the generation of harmonics is prevented.

[0048]

According to the power supply device of the first aspect, since each load is provided with a resonance circuit having a small-capacity capacitor that substantially discharges when the switching element of the inverter circuit is turned on and off, each resonance circuit is provided. Since the resonance circuit of 1 can be made uniform, it is possible to eliminate variations in each load.

According to the power supply device of the second aspect, in addition to the power supply device of the first aspect, the load attachment / detachment detecting means detects the connection state of the load based on the voltage of the small-capacity capacitor, so that the configuration is simple. The mounting condition of the load can be detected.

According to the power supply device of the third aspect, in addition to the power supply device of the second aspect, the capacity of the large-capacity capacitor is changed by the capacity changing means in accordance with the amount of the load detected by the load attachment / detachment detecting means. The capacity can be changed according to the amount of load, and the efficiency can be improved.

According to the discharge lamp lighting device of the fourth aspect,
Since the load of the power supply device according to claim 1 or 2 is a discharge lamp, it is possible to suppress variations in brightness of the discharge lamp.

According to the discharge lamp lighting device of the fifth aspect,
Since the discharge lamp lighting device according to the fourth aspect is provided with the instrument body, it is possible to suppress variations in the brightness of the discharge lamp.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a discharge lamp lighting device of the present invention.

FIG. 2 is a perspective view showing the same illumination device.

FIG. 3 is a waveform diagram showing the same operation. (A) Voltage of capacitor C9 (b) Voltage of capacitor C3 (c) Voltage of capacitors C11 and C12 (d) Voltage of diode D11 and diode D12 (e) Input current

FIG. 4 is a circuit diagram showing a discharge lamp lighting device of another embodiment of the same.

FIG. 5 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the above.

[FIG. 6] Capacitor C11 and capacitor C1 showing the same operation
It is a waveform diagram of 2. (A) When fluorescent lamp is installed (b) When fluorescent lamp is not installed

FIG. 7 is a circuit diagram showing a discharge lamp lighting device of still another embodiment of the same.

FIG. 8 is a circuit diagram showing a conventional discharge lamp lighting device.

[Explanation of symbols]

3 Inverter circuit 4, 5, 6 Resonance circuit 11 Instrument main body 21 Attachment / detachment detection circuit as load attachment / detachment detection means 25 Switching device as capacity changing means C3, C21 Large-capacity capacitors C11, C12, C13 Small-capacity capacitors FL1, FL2 , FL3 load, fluorescent lamp as discharge lamp Q1, Q2 Field effect transistor as switching element

Claims (5)

[Claims] 1. A power supply circuit in which a load is connected in parallel to an inverter circuit that oscillates and outputs a switching element, and a resonance circuit having a small-capacity capacitor that is substantially discharged when the switching element is turned on and off. A power supply device characterized by being provided for each of the loads. 2. The power supply device according to claim 1, further comprising a load attachment / detachment detecting means for detecting a connection state of the load based on a voltage of a small capacity capacitor. 3. A large-capacity capacitor connected to the input side of the inverter circuit and having a larger capacity than the capacitor of the resonance circuit, and the capacity of the large-capacity capacitor based on the connection state of the load detected by the load attachment / detachment detection means. 3. The power supply device according to claim 2, further comprising: a capacitance varying unit that varies the voltage. 4. A discharge lamp lighting device, wherein the load of the power supply device according to claim 1 or 2 is a discharge lamp. 5. A lighting device comprising the discharge lamp lighting device according to claim 4 and a fixture body.