JPH11162682A - Discharge lamp lighting device and lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a safe operation, by detecting the lamp-life ending stage of a discharge lamp. SOLUTION: Thermal fuses 4a1 to 4a4 are provided in respective lead wires on the power supply side and on the non-power supply side of a discharge lamp 4 in order to release filaments 4d when the lamp-life ending stage is detected in terms of temperature in the neighborhood of the filaments 4d of a luminous tube bulb 4b, and a feedback current to a main switch element of a self-excitation inverter circuit 3 for converting a direct current obtained by a rectifying part 2 into a high-frequency alternating current and performing high-frequency lighting of the discharge lamp 4, is taken out from the anti-power supply side and fed back to the inverter circuit 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp lighting device and a lighting device having a function of detecting the end of lamp life of a discharge lamp.

[0002]

2. Description of the Related Art For example, a fluorescent lamp, which is a discharge lamp, is formed by forming a phosphor film on the inner surface of an arc tube and closing the tube end of the arc tube with a sealing member. A pair of internal leads are hermetically pierced through the sealing member, and a filament coil is wound around the inner ends of these internal leads to form a filament circuit. In a compact fluorescent lamp, the arc tube bulb is formed in a U-shape or the like to achieve miniaturization.

On the other hand, an electron emitting material is applied to the filament, and when a current is applied to an electrode (cathode) to preheat the filament, thermoelectrons are emitted from the filament, and the thermoelectrons are emitted to the opposite electrode (anode). It is pulled and moved to start discharge. Thereby, the fluorescent lamp is turned on.

Here, the fluorescent lamp (discharge lamp) is lit by a discharge lamp lighting device. In the case of a high-frequency lighting system, an alternating current having a commercial frequency (50 Hz or 60 Hz) is rectified by a rectifying unit and is once rectified. The fluorescent lamp is lit at a high frequency (for example, 20 kHz to 100 kHz) by an inverter circuit.

When the fluorescent lamp is turned on or off for a long period of time, a filament constituent material such as tungsten, which is mainly used as a filament material, scatters,
It adheres and deposits on the tip surface of the sealing member near the filament, and when the filament is broken, current flows through the scattered and deposited conductor to generate heat. Also, if the lighting is maintained at the end of life and the electron emitting material applied to the filament is scattered or is turned on or off, the filament of the fluorescent lamp is overheated due to this heat generation, and the socket is melted or a valve crack occurs.

To prevent this, a safety circuit is provided in the inverter circuit to detect a half-wave discharge generated at the end of the lamp life or to detect an open voltage when the lamp is not lit, thereby reducing the output of the inverter circuit. Or, a safety operation of stopping is performed. In this case, the inverter circuit becomes relatively expensive.

Therefore, a temperature fuse is provided in the discharge lamp, and when the filament portion of the fluorescent lamp is overheated, the filament circuit is opened to keep the discharge lamp in a safe state.

FIG. 5 is a circuit diagram of a conventional discharge lamp lighting device. The commercial AC power supply 1 having a frequency of 50 Hz or 60 Hz is input to the rectifier 2 of the discharge lamp lighting device, and is converted into DC by the rectifier 2. The rectifier 2 is a full-wave rectifier 2a
And a smoothing capacitor 2b. The DC obtained by the rectifying unit 2 is input to the inverter circuit 3 and is set to a frequency of 20 kHz to 100 kHz.
The discharge lamp 4 is converted into a high-frequency alternating current of kHz to illuminate the discharge lamp 4 at a high frequency. That is, the DC obtained by the rectifier 2 is input to the lighting LC circuit 3b of the discharge lamp 4 via the power factor improving LC circuit 3a of the inverter circuit 3, and the output of the inverter circuit 3 is controlled by the control means 3c. You.

The discharge lamp 4 has four thermal fuses 4a1.
To 4a4, and the thermal fuses 4a1 to 4a4 are provided.
Reference numeral 4a4 detects the end of the lamp life based on the temperature in the base near the filament 4d in the arc tube bulb 4b. When the temperature reaches a predetermined set temperature, the lamp circuit is opened to open the filament circuit. That is, when the end of the lamp life is detected, the filament 4 d is output from the inverter circuit 3.
Safety operation to cut off the supply of high frequency power to the

When the discharge lamp 4 is turned on, the capacitor C1 of the lighting LC circuit 3b acts as a capacitor for preheating the filament 4d, and after the discharge lamp 4 is turned on, forms a resonance circuit together with the coil L1 of the lighting LC circuit 3b. It acts as a resonance capacitor for high frequency lighting.

When the discharge lamp 4 is started, power is supplied as follows. Via the coil L1 of the lighting LC circuit 3b, the temperature fuse 4a1 of the discharge lamp 4, the filament 4
d, thermal fuse 4a2, capacitor C1 of lighting LC circuit, thermal fuse 4a3 of discharge lamp 4, filament 4
d. Return to the rectifier 2 via the thermal fuse 4a4. That is, a current is applied to the filament 4d through the capacitor C1 of the lighting LC circuit 3b to preheat the filament 4d. Here, the temperature fuse 4a of the discharge lamp 4
1, 4a4 are connected to the inverter circuit 3 on the power supply side and are therefore referred to as power supply-side thermal fuses. Temperature fuse.

When the discharge lamp 4 starts to discharge, a parallel circuit of the capacitor C1 of the lighting LC circuit 3b and the discharge lamp 4 is formed. Then, the control means 3c operates the inverter circuit 3 at a high frequency based on the feedback current from the feedback current transformer 5 provided on the power supply side.

[0013]

However, when the inverter circuit 3 is a self-excited inverter circuit of the capacitor preheating type as shown in FIG.
During the operations of 4a4, the self-excited oscillation operation may be extremely deteriorated. For example, when the temperature in the base near the filament 4d in the arc tube bulb 4b rises and the temperature fuse 4a2 of the discharge lamp 4 operates first, the filament circuit is opened, but the temperature fuses 4a1 and 4a4 on the power supply side.
Is inoperative, so discharge may continue between the filaments 4d.

In this case, since the inverter circuit 3 is a self-excited type that operates with the feedback current fed back by the feedback current transformer 5 provided on the power supply side, when the discharge continues between the filaments 4d, the feedback current is reduced. A feedback current is generated via the flower 5, and the control means 3c controls the main switch element Tr based on the feedback current. That is, the inverter circuit 3 continues to operate in an abnormal state different from the normal feedback current.

As described above, in the case of the self-excited inverter circuit, when the non-power-supply-side temperature fuse is operated first at the end of the lamp life, the discharge lamp continues to discharge and the resonance state is abnormally controlled. In some cases, the discharge lamp cannot be held safely.

An object of the present invention is to provide a discharge lamp lighting device and an illuminating device capable of detecting the end of the lamp life of a discharge lamp and reliably performing a safe operation.

[0017]

According to a first aspect of the present invention, there is provided a discharge lamp lighting device, comprising: a power supply for a thermal fuse for opening a filament circuit when an end of lamp life is detected based on a temperature near a filament of an arc tube bulb; A discharge lamp provided in each of the lead wires of the power supply side and the non-power supply side; a rectifier for converting commercial AC into DC; a DC having a main switch element and converting the DC obtained by the rectifier into high-frequency AC and discharging A self-excited inverter circuit for lighting an electric lamp at a high frequency; and a feedback current transformer for extracting a feedback current to a main switch element of the inverter circuit from a non-power supply side.

The vicinity of the filament in the arc tube bulb is as follows.
This is the tip surface of the sealing member that closes the end of the arc tube bulb.The thermal fuse is used when current flows through the conductor scattered and adheres to the tip surface of the sealing member and the temperature at which heat is generated or the electron emitting material disappears. Sensitive to excessive heat generation of the filament when the lighting is maintained.

The detection of the end of the lamp life is determined by setting the sensitive temperature of the thermal fuse. When the thermal fuse is activated, the filament circuit for supplying power to the filament is cut off.

Commercial AC power supply is 50Hz or 60Hz
The frequency for lighting the discharge lamp at a high frequency in the inverter circuit is preferably 20 kHz to 100 kHz.

The power supply side is the output terminal side of the inverter circuit, and the non-power supply side is the opposite side via a discharge lamp. The self-excited type means that the output of the inverter is indirectly or directly fed back to drive the main switch element.

During operation of the thermal fuse, the non-power supply side is opened from the power supply, so that the feedback current from the primary winding of the feedback current transformer provided on the non-power supply side becomes zero. Therefore, when the thermal fuse operates, the inverter circuit stops operating.

According to the discharge lamp lighting device of the first aspect, the end of the lamp life is detected by the temperature fuse provided in the discharge lamp, and the drive control of the main switch element of the inverter circuit is controlled by the feedback detected on the non-power supply side. Because it is based on the current,
The operation of the inverter circuit is continued with the resonance state being abnormal, and the discharge lamp is maintained in a safe state.

According to a second aspect of the present invention, there is provided a discharge lamp lighting device according to the first aspect, wherein the temperature fuse connected to the power supply side lead wire is connected to the non-power supply side lead wire. It is characterized by being arranged at a position closer to the filament than the fuse.

According to the discharge lamp lighting device according to the second aspect of the present invention, in addition to the operation of the discharge lamp lighting device of the first aspect, the temperature fuse connected to the lead wire on the power supply side is connected to the filament of the arc tube bulb. It is arranged at a close position. Therefore, it is easily affected by the heat generated from the filament part of the arc tube bulb, and operates before the thermal fuse connected to the lead wire on the non-power supply side. As a result, the discharge lamp does not continue discharging at the end of the lamp life, and the discharge lamp can be maintained in a safe state.

According to a third aspect of the present invention, there is provided the discharge lamp lighting device according to the first aspect, wherein the operation set temperature of the temperature fuse connected to the power supply side lead wire is set to the non-power supply side lead wire. The temperature is set lower than the operation set temperature of the connected thermal fuse.

According to the discharge lamp lighting device of the third aspect of the present invention, in addition to the function of the discharge lamp lighting device of the first aspect, the thermal fuse connected to the power supply side lead wire is connected to the non-power supply side lead wire. Because the operating temperature is set lower than that of the thermal fuse connected to the power supply, it is more susceptible to the heat generated from the filament part of the arc tube bulb, and it is earlier than the thermal fuse connected to the lead wire on the non-power supply side. Works. Therefore, it is easily affected by the heat generated from the filament part of the arc tube bulb, and operates before the thermal fuse connected to the lead wire on the non-power supply side. Therefore, the discharge lamp does not continue discharging at the end of the lamp life, and the discharge lamp can be maintained in a safe state.

A discharge lamp lighting device according to a fourth aspect of the present invention is the discharge lamp lighting device according to any one of the first to third aspects, wherein the temperature fuse is arranged in a horizontal direction when the discharge lamp is used. It is characterized by being installed diagonally with a predetermined angle in the vertical direction.

The use state of the discharge lamp means a state in which the discharge lamp is mounted on the appliance main body. For example, in the case of vertical lighting in which the discharge lamp is mounted in the appliance main body in a vertical direction, or when the discharge lamp is horizontally mounted on the appliance main body. It refers to the case of horizontal lighting attached to the.

With the discharge lamp mounted on the fixture body, the thermal fuse is arranged obliquely from the horizontal direction to the vertical direction. The predetermined angle in this case is arranged so as to have about 45 °. This is to prevent the conductive member from fusing when the thermal fuse operates and the fused conductive member from spreading to the surroundings to make it impossible to secure an insulation distance, thereby preventing a discharge or short circuit in the thermal fuse.

According to the fourth aspect of the present invention, when the thermal fuse operates and the conductive member is blown, the blown conductive member moves downward by gravity, so that the insulation distance after the blow can be secured. Therefore, the operation of the thermal fuse can be assured.

According to a fifth aspect of the present invention, there is provided an illuminating device comprising: the discharge lamp lighting device according to any one of the first to fourth aspects; and a fixture main body to which the discharge lamp lighting device is mounted. It is characterized by.

The rectifier and the inverter circuit constituting the discharge lamp lighting device are housed inside the fixture body, and the discharge lamp is mounted outside to form a lighting device.

According to the fifth aspect of the present invention, it is possible to provide a safe illuminating device that can detect the end of the lamp life and can reliably perform a safe operation and does not expose the discharge lamp to an abnormal state.

[0035]

Embodiments of the present invention will be described below. FIG. 1 is a circuit configuration diagram of a discharge lamp lighting device according to an embodiment of the present invention. This embodiment is different from the conventional example shown in FIG. 5 in that the primary side of the feedback current transformer 5 is provided with a lighting LC.
This is provided in series with the capacitor C1 of the circuit, and the secondary side of the feedback current transformer 5 is interposed in the control terminal of the output switch element TR of the inverter circuit. Thereby, the feedback current to the main switch element of the inverter circuit 3 is taken out from the non-power supply side and inputted to the control means 3c of the inverter circuit 3.

In FIG. 1, a commercial AC power supply 1 is an AC having a frequency of 50 Hz or 60 Hz, and this AC is input to a rectifier 2 of a discharge lamp lighting device. The rectifier 2 includes a full-wave rectifier 2a and a smoothing capacitor 2b. The DC obtained by the rectifier 2 is input to the inverter circuit 3 and is converted into a high-frequency power supply for lighting the discharge lamp 4. That is, the discharge lamp 4 is lit at a high frequency by a high-frequency alternating current of 20 kHz to 100 kHz converted by the inverter circuit 3.

In the inverter circuit 3, the direct current obtained by the rectifier 2 is input to the lighting LC circuit 3b of the discharge lamp 4 via the power factor improving LC circuit 3a of the inverter circuit 3. The power input to the lighting LC circuit 3b is controlled by the control unit 3c.

Next, the discharge lamp 4 has a total of four thermal fuses 4a1 to 4a4, two on each of the power supply side and the non-power supply side.
Is provided. The power supply side is an output terminal side of the inverter circuit 3, and temperature leads 4a1 and 4a4 are connected to lead wires on the power supply side. The non-power supply side is the opposite side via the discharge lamp 4, and temperature fuses 4a2 and 4a3 are connected to the lead wires on the non-power supply side.

The temperature fuses 4a1 to 4a4 detect the end of the lamp life based on the temperature in the base near the filament 4d in the arc tube bulb 4b. When the predetermined temperature is reached, the temperature fuses 4a1 to 4a4 are activated to open the filament circuit. Has become. That is, when the end of the lamp life is detected, a safe operation of shutting off the supply of high frequency power from the inverter circuit 3 to the filament 4d is performed.

The lighting LC circuit 3b has a coil L1 and a capacitor C1, and a primary winding 5a of a feedback current transformer 5 for supplying a control feedback current to the main switch element Tr of the control means 3c. Is provided. The primary winding 5a of the feedback current transformer 5 and the capacitor C1 are provided in the inverter circuit 3 on the non-power supply side.

The inverter circuit 3 is a self-excited inverter circuit. The feedback current from the primary winding 5a of the feedback current transformer 5 provided on the non-power supply side is controlled by the feedback current provided by the control means 3c. It is supplied to the secondary winding 5b of the flower 5. Thereby, the control unit 3c controls the drive of the main switch element Tr of the inverter circuit 3 based on the feedback current from the primary winding 5a of the feedback current transformer 5 on the non-power supply side.

Now, it is assumed that the temperature inside the base near the filament 4d in the arc tube bulb 4b rises, and the temperature fuse 4a2 on the non-power supply side operates first. In this case, since the filament circuit is opened, the capacitor C1, which is an inverter circuit on the non-power supply side, and the primary winding 5a of the feedback current transformer 5 are also opened, and no power supply current flows.

For example, the thermal fuses 4a1, 4
Since a4 is inactive, no current flows through the primary winding 5a of the feedback current transformer 5 on the non-power supply side even if the discharge continues between the filaments 4d. Therefore, the control means 3c
No feedback current flows through the secondary winding 5b of the current transformer 5 for feedback, so that the inverter circuit 3 does not operate due to abnormal resonance.

As described above, in the inverter circuit 3, when the thermal fuse 4a operates, the feedback current from the primary winding 5a of the feedback current transformer 5 provided on the non-power supply side becomes zero.
When the thermal fuse 4a operates, the operation is stopped.
Accordingly, the operation of the inverter circuit continues even when the resonance state is abnormal, and the discharge lamp 4 is maintained in a safe state.

FIG. 2 is an explanatory diagram showing an example of the discharge lamp 4 according to the embodiment of the present invention. Discharge lamp 4 shown in FIG.
Shows a compact fluorescent lamp in which the arc tube 4b is formed in a U-shape to reduce the size, and the temperature fuses 4a1 to 4a4 are provided inside the socket portion 4c. Further, current flows through the conductor scattered and adhered to the temperature fuses 4a1 to 4a4 in the vicinity of the filament 4d in the arc tube bulb 4b, that is, at the tip end surface of the sealing member 4e for closing the end of the arc tube 4b. The end of the lamp life is detected by detecting the temperature when heat is generated.

The temperature fuses 4a1 and 4a4 connected to the power supply side lead wire are located closer to the filament 4d than the temperature fuses 4a2 and 4a3 connected to the non-power supply side lead wire.

Therefore, the thermal fuses 4a1 and 4a4 connected to the power supply side lead wire are easily affected by the heat generated from the filament 4d of the arc tube bulb 4b, and the thermal fuse 4a2 connected to the non-power supply side lead wire. , Operates before 4a3. As a result, the inverter circuit 3 on the power supply side and the discharge lamp 4 are opened first, so that the discharge lamp 4 does not continue discharging at the end of the lamp life, and the discharge lamp 4 can be maintained in a safe state.

Next, FIG. 3 is an explanatory view showing another example of the discharge lamp 4 according to the embodiment of the present invention. In the discharge lamp 4 shown in FIG. 3, the temperature fuses 4a1 to 4a4 are attached at substantially the same positions from the filament 4d as the discharge lamp 4 shown in FIG. The operation set temperatures of the fuses 4a1, 4a4 are set lower than the operation set temperatures of the temperature fuses 4a2, 4a3 connected to the non-power-supply-side lead wire.

As a result, as in the case of the discharge lamp 4 shown in FIG.
1, 4a4 are easily affected by the heat generated from the filament 4d of the arc tube bulb 4b, and operate before the thermal fuses 4a2, 4a3 connected to the lead wires on the non-power supply side. Therefore, the inverter circuit 3 on the power supply side is opened earlier than the discharge lamp 4, so that the discharge lamp 4 does not continue discharging at the end of the lamp life, and the discharge lamp 4 can be maintained in a safe state. Moreover, compared to the discharge lamp 4 of FIG. 2, it is effective when there is not enough room for arranging the thermal fuses 4a1 to 4a4.

Here, the temperature fuses 4a1 to 4a1 of the discharge lamp 4
4a4 is attached to the discharge lamp 4 and arranged.
The discharge lamp 4 is installed so as to maintain an oblique direction at a predetermined angle from a horizontal direction to a vertical direction in a use state of the discharge lamp 4.

When the discharge lamp 4 is used, the discharge lamp 4 is mounted on the appliance body. For example, there is a case of vertical lighting in which the discharge lamp 4 is mounted vertically to the appliance main body, and a case of horizontal lighting in which the discharge lamp 4 is mounted horizontally above the appliance main body. Regardless of the use state, the temperature fuse 4a1
4a4 are arranged obliquely at a predetermined angle from the horizontal direction to the vertical direction. Therefore, the predetermined angle at that time is arranged so as to have an angle of about 45 ° in order to be oblique in any use state.

This is because, when the thermal fuses 4a1 to 4a4 operate, the conductive members are blown, and the blown conductive members are spread around in the thermal fuses 4a1 to 4a4, so that an insulation distance cannot be secured. . That is, since the blown conductive member may spread around in the thermal fuses 4a1 to 4a4 and cause a discharge in the thermal fuses 4a1 to 4a4, this is to prevent the occurrence.

In this way, the temperature fuses 4a1 to 4a1
When the conductive member 4a4 operates and blows, the blown conductive member moves downward by gravity, so that the insulation distance after the blow can be secured. Therefore, the thermal fuses 4a1 to 4a1
The operation of 4a4 can be assured.

The discharge lamp lighting device configured as described above is mounted on the fixture body 6 to form a lighting device as shown in FIG. That is, the rectifying unit 2 and the inverter circuit 3 constituting the discharge lamp lighting device are housed inside the fixture main body 6, and the discharge lamp 4 is mounted outside the fixture main body 6 to form a lighting device. According to this lighting device, the end of the lamp life is detected, and the safe operation can be performed more accurately, so that the discharge lamp 4 can be used safely without being exposed to an abnormal state.

[0055]

As described above, according to the first aspect of the present invention, the end of the lamp life is detected by the thermal fuse provided in the discharge lamp, and the drive control of the main switch element of the inverter circuit is performed. Since the operation is performed based on the feedback current detected on the non-power supply side, the operation of the inverter circuit does not continue while the resonance state is abnormal, and the discharge lamp is maintained in a safe state.

According to the second and third aspects of the invention, the discharge lamp does not continue to discharge at the end of the lamp life, and the discharge lamp can be maintained in a safer state.
Further, in the invention of claim 3, compared with the invention of claim 2,
This is effective when there is not enough room for disposing the thermal fuse.

According to the fourth aspect of the invention, the operation of the thermal fuse can be ensured regardless of the use state of the discharge lamp.

According to the fifth aspect of the present invention, since the end of the lamp life is detected and the safe operation can be performed more accurately, it is possible to obtain a lighting device that does not expose the discharge lamp to an abnormal state.

[Brief description of the drawings]

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

FIG. 2 is an explanatory diagram showing an example of a discharge lamp used in the embodiment of the present invention.

FIG. 3 is an explanatory view showing another example of the discharge lamp used in the embodiment of the present invention.

FIG. 4 is a perspective view of a lighting device according to the embodiment of the present invention.

FIG. 5 is a circuit configuration diagram of a conventional discharge lamp lighting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Commercial AC power supply 2 Rectifier 3 Inverter circuit 4 Discharge lamp 4a Thermal fuse 4b Arc tube bulb 4d Filament 5 Current transformer for feedback 6 Instrument body

Claims (5)

[Claims] A discharge lamp having a temperature fuse for opening a filament circuit on each of a lead wire on a power supply side and a non-power supply side when an end of lamp life is detected based on a temperature near a filament of an arc tube bulb; A rectifier for converting commercial alternating current to direct current; a self-excited inverter circuit having a main switch element for converting direct current obtained by the rectifier to high-frequency alternating current and lighting the discharge lamp at high frequency; A discharge current transformer for extracting a feedback current to the main switch element of the inverter circuit from the non-power supply side. 2. The thermal fuse connected to the power supply side lead wire is located closer to the filament than the thermal fuse connected to the non-power supply side lead wire. 2. The discharge lamp lighting device according to claim 1. 3. An operation set temperature of a temperature fuse connected to the power supply side lead wire is set lower than an operation set temperature of the temperature fuse connected to the non-power supply side lead wire. The discharge lamp lighting device according to claim 1. 4. The discharge lamp lighting device according to claim 1, wherein the thermal fuse comprises:
A discharge lamp lighting device characterized in that the discharge lamp lighting device is installed obliquely at a predetermined angle from a horizontal direction to a vertical direction in a use state of the discharge lamp. 5. A lighting device, comprising: the discharge lamp lighting device according to claim 1; and a fixture main body to which the discharge lamp lighting device is mounted.