JPH11162413A - Metal halide lamp with built-in starter having pulse stopping function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve restarting performance with a pulse stopping function being maintained in the time of normal starting, in a metal halide lamp with a built-in starter including a nonlinear ceramic capacitor with the pulse stopping function. SOLUTION: This lamp is provided with a series circuit composed of the first bimetal switch 5, a non-linear ceramic capacitor 6, a current damper 7 and a semiconductor switch 8, connected in parallel with an emission tube 1, and a series circuit composed of a pulse stopping resistive element 10 which can heat the non-linear ceramic capacitor 6 to Curie temperature and the second bimetal switch 12, connected in parallel with the series circuit of the non-linear ceramic capacitor 6, the current damper 7 and the semiconductor switch 8. In the time of restarting after the turning-off, the first bimetal switch 5 is turned on before the second bimetal switch 12 is turned on, then the lamp is restarted under the condition that the pulse stopping resistive element 1 is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal halide lamp having a built-in starter including a non-linear ceramic capacitor having a pulse stopping function and a semiconductor switch.
In particular, the present invention relates to a metal halide lamp with a built-in starter and improved restart performance.

[0002]

2. Description of the Related Art Conventionally, as a starter of a metal halide lamp, barium titanate having a non-linear VQ characteristic or the like has been proposed in order to solve problems such as stability of operation and life of a starter having a high-voltage pulse generating circuit. The use of a non-linear ceramic capacitor (abbreviated as FEC) mainly composed of a ferroelectric material has been used. This uses a saturation characteristic of a nonlinear ceramic capacitor to generate a pulse voltage every half cycle by the inductance of a ballast or the like connected in series with the nonlinear ceramic capacitor and apply the pulse voltage to a metal halide lamp to start the lamp. Next, a configuration example of a metal halide lamp having such a starter will be described with reference to FIG.

In FIG. 2, reference numeral 1 denotes a metal halide lamp arc tube, in which main electrodes 2a and 2b are sealed at both ends of a quartz glass tube, and an auxiliary electrode 3 is further sealed close to at least one of the main electrodes 2a. And metal halides such as mercury and scandium and sodium are sealed therein together with a starting auxiliary gas. A starting auxiliary circuit in which a starting auxiliary resistor 4 and a normally-closed bimetal switch 5 are connected in series is provided between the auxiliary electrode 3 and the opposing main electrode 2a, and is provided in parallel with the arc tube 1. A series circuit of a non-linear ceramic capacitor 6, a current damper 7, and a bidirectional semiconductor switch 8 such as an SSS element is connected via a bimetal switch 5, and a phase stabilizing resistor is connected in parallel with the semiconductor switch 8. The body 9 is connected. And each of the above components is housed in the outer sphere 11,
A metal halide lamp is configured, and is connected to an AC power supply 22 via a ballast 21 such as a choke coil and is turned on.

Next, the operation of the thus configured metal halide lamp will be described. When the power supply 22 is turned on, the AC power supply voltage is applied to the series circuit of the nonlinear ceramic capacitor 6, the current damper 7, and the semiconductor switch 8 via the ballast 21. Is exceeded, the abrupt charging of the non-linear ceramic capacitor 6 is performed, and the charging current is changed when the charging charge is saturated,
That is, when the saturation voltage of the nonlinear ceramic capacitor 6 is reached, the value suddenly becomes zero. At this time, a large positive pulse voltage is generated due to the inductance of the ballast 21 and applied between the main electrode 2a and the auxiliary electrode 3 and between the main electrodes 2a and 2b together with the power supply voltage. Negative pulse voltages are similarly generated in the next negative half cycle, and a glow discharge is first generated between the main electrode 2a and the auxiliary electrode 3 by these pulse voltages. During this time, an arc discharge occurs. As described above, since the discharge starts from the narrow gap between the main electrode 2a and the auxiliary electrode 3, it can be easily started with a relatively low pulse voltage.

[0005] Incidentally, in a metal halide lamp having a built-in starter including a non-linear ceramic capacitor as described above, there may be a case where the lamp is defective. When the lamp is not in a state, a pulse is continuously generated by the built-in starter. If the pulse continues to be generated at the time of lamp failure as described above, not only does the insulation of the ballast and the insulation of the lighting equipment deteriorate, but also the pulse voltage continues to be applied to the lamp base and the like.
Dangerous to the human body.

In order to solve such a problem, as shown in FIG.
In a metal halide lamp with a built-in starter, which is connected in parallel with a starter including a non-linear ceramic capacitor 6, the temperature of the non-linear ceramic capacitor 6 is connected in parallel with a series circuit including the non-linear ceramic capacitor 6, and the Curie temperature There has been proposed a configuration in which a pulse stopping resistor 10 capable of heating up to (usually 90 ° C.) is arranged close to the nonlinear capacitor 6.

In the metal halide lamp thus configured, if the starter including the non-linear ceramic capacitor 6 operates but the arc tube 1 does not turn on, the starter continues to generate high-voltage pulses. With the self-heating of the capacitor 6 and the heat of the pulse stopping resistor 10 arranged close to the nonlinear ceramic capacitor 6, the temperature of the nonlinear ceramic capacitor 6 reaches the Curie temperature in a short time, and the nonlinear ceramic capacitor 6 is always It becomes dielectric and the non-linear characteristics disappear. Therefore, it is possible to stop the generation of the high-voltage pulse at the time of a failure in a short time.

The pulse stopping resistor 10 not only has the function of stopping the generation of the high-voltage pulse as described above, but also reduces the voltage applied to the nonlinear ceramic capacitor 6 during lamp operation. It has a function of passing a pyroelectric current generated when the temperature exceeds the Curie temperature of about 90 ° C. to prevent its characteristic deterioration.

[0009]

In a metal halide lamp having a built-in starter including a non-linear ceramic capacitor, if a pulse stopping function is added by connecting a pulse stopping resistor as described above, the non-linear ceramic capacitor is included. The generated pulse voltage of the starter decreases. This does not cause a drop in the generated pulse voltage during normal startup, but at restart, the lamp will not restart if the pulse voltage generated by the starter for restart is performed early after turning off the light. There is. This is because the pulse voltage is attenuated by connecting the pulse stopping resistor, and the temperature of the nonlinear ceramic capacitor constituting the starter is high at the time of restart. This is because the generated pulse voltage decreases. If the pulse voltage generation time for restart is delayed, the lamp is restarted, but it may be necessary to pass 15 minutes or more after turning off the lamp.

The time from when the light is turned off until the restart operation is started depends on the closing operation time of the bimetal switch connected to the starter with the built-in lamp. Problems arise. Also,
If the value of the pulse stop resistor connected to the starter with built-in lamp is increased, the attenuation of the pulse voltage is reduced, so that even if the generation of the pulse voltage for restart is performed early after turning off the light, Although it can be restarted, if the value of the pulse stop resistor is increased, there is a problem that the pulse stop function at the time of normal startup does not work completely.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems in a metal halide lamp having a built-in starter including a non-linear ceramic capacitor having a pulse stop function. It is another object of the present invention to provide a metal halide lamp with a built-in starter that can improve restart performance.

[0012]

In order to solve the above-mentioned problems, the present invention provides first and second main electrodes at the ends of a quartz tube and an auxiliary electrode at least in proximity to the second main electrode. And an arc tube in which a metal halide is sealed together with a starting auxiliary gas, and at least a first bimetal switch, a non-linear ceramic capacitor, and a semiconductor switch connected in series. A starting circuit connected between the second main electrode, a starting auxiliary resistor connected between a connection point between the first bimetal switch and the non-linear ceramic capacitor and the auxiliary electrode, and at least in parallel with the non-linear ceramic capacitor. A series circuit of a pulse stopping resistor and a second bimetal switch capable of heating the temperature of the connected nonlinear ceramic capacitor to the Curie temperature At least a resistor for preventing deterioration of the non-linear ceramic capacitor connected in parallel to the non-linear ceramic capacitor is housed in an outer sphere filled with an inert gas, and the first and second bimetal switches are It is closed at the time of starting, opened at the time of lighting, and at the time of restarting after the light is turned off, the first bimetal switch is closed before the second bimetal switch is closed, and the pulse stopping resistor is disconnected. A metal halide lamp with a built-in starter is configured so that it is restarted in a state where it is shut down.

In the metal halide lamp with a built-in starter configured as described above, the second bimetal switch is closed together with the first bimetal switch at the time of normal starting, and the pulse stopping resistor is at least a non-linear ceramic. It is connected in parallel with the capacitor, so when there is no point, the temperature of the nonlinear ceramic capacitor reaches the Curie temperature in a short time due to the heat generated by the pulse stopping resistor, and the generation of the high-voltage pulse can be stopped in a short time. it can. On the other hand, when restarting after turning off the light, the second
The restart operation is performed with the bimetal switch open and the pulse stop resistor disconnected, so that the pulse voltage does not attenuate due to the pulse stop resistor, restarting is easily performed, and restart performance is improved. Can be improved.

[0014]

Next, an embodiment will be described. FIG. 1 is a circuit diagram showing an embodiment of a metal halide lamp with a built-in starter according to the present invention. Components identical or corresponding to those in the conventional example shown in FIGS. Is shown. In FIG. 1, reference numeral 1 denotes a 700 W metal halide lamp arc tube, which has main electrodes 2a and 2b and one main electrode 2a at both ends of a quartz glass tube having an internal volume of about 40 cc.
Auxiliary electrode 3 is sealed in the vicinity of, and about 2600 Pa of argon gas, about 65 mg of mercury, and about 60 mg of scandium and sodium iodide as metal halide are sealed therein as a starting auxiliary gas. I have. Auxiliary electrode 3
A starting auxiliary circuit in which a starting auxiliary resistor 4 of 100 kΩ and a first bimetal switch 5 which is normally closed (open when the lamp is turned on) is connected in series is connected between the main electrode 2a and the main electrode 2a. In addition, a disc-shaped nonlinear ceramic capacitor 6
And the current damper 7 and the breakover voltage of about 170
A series circuit with a semiconductor switch 8 composed of a V SS element is connected in parallel to the arc tube 1 via a first bimetal switch 5, and these nonlinear ceramic capacitor 6, current damper 7, and semiconductor switch 8 15 kΩ (1/4 W standard) for heating the nonlinear ceramic capacitor 6 to the Curie temperature in parallel with the series circuit of
A series circuit of a pulse stop resistor 10 and a normally closed (open when the lamp is turned on) second bimetal switch 12 is connected to a 100 kΩ
A resistor 13 for preventing deterioration of the (1/4 W standard) nonlinear ceramic capacitor 6 is connected, and a resistor 9 for phase stabilization of 55 kΩ is connected in parallel with the semiconductor switch 8.

As the non-linear ceramic capacitor 6, a metal electrode film having a diameter of 16 mm is formed on both sides of a ferroelectric ceramic substrate mainly composed of barium titanate having a diameter of 18 mm and a thickness of 1.0 mm. A pin-shaped terminal lead which is formed by welding is used. The distance between the terminal lead of the nonlinear ceramic capacitor 6 and the end of the pulse stopping resistor 10 is 3 mm. The distance between the pulse stop resistor 10 and the lead is set to 4 mm. Then, the above-described components are housed in the outer sphere 11 in the same manner as the conventional one, and at the time of restart after the lamp is turned off, the first bimetal switch 5 is closed before the second bimetal switch 12 is closed. The operating characteristics of the first and second bimetallic switches 5 and 12 are set so that a restart operation is performed in a state in which the pulse stop resistor 10 is cut off and the starter built-in type. Metal halide lamp.

The metal halide lamp thus constructed is supplied to a 200 V, 50 Hz through a 700 W mercury lamp ballast 21.
When the start-up operation is performed by turning on the AC power supply 22, the first and second bimetallic switches 5 and 12 are both closed at the time of start-up, and the nonlinear ceramic capacitor 6 is connected to the pulse stopping resistor 10 or the arc tube 1 As in the conventional example shown in FIG. 3, a high pulse voltage is generated, and the pulse voltage is slightly reduced by the pulse stop resistor 10, but the start-up lighting is easily performed. Can be.

In the case of a non-point state at the time of starting, the temperature of the nonlinear ceramic capacitor 6 is reduced in a short time due to the heat generated by the pulse stopping resistor 10 arranged close to the nonlinear ceramic capacitor 6. , And the generation of the high-voltage pulse can be stopped in a short time.

At the time of restarting after turning off the light, the first and second bimetal switches 5 and 12 in the open state during lighting operate in the following order to restart the lamp. (1) When the power is turned on again after the light is turned off, first, the first bimetal switch 5 is closed as the lamp cools down, and the auxiliary electrode 3 and the main electrode 2 arranged close to the auxiliary electrode 3 in the arc tube 1.
A discharge occurs between the discharge current and the discharge current a. (2) Since the pulse stopping resistor 10 is disconnected by opening the second bimetal switch 12, the non-linear ceramic capacitor 6 becomes 90 ° C. with time as the arc tube cools.
After cooling down (about 9 minutes after turning off the light), the nonlinear characteristics are restored and a pulse voltage (about 500 V) is generated. (3) The arc tube 1 also cools down with time, and the pulse voltage required for restarting decreases. (4) The nonlinear ceramic capacitor 6 further cools down with time, the generated pulse voltage rises to reach the pulse voltage required for restart, and the lamp restarts. (5) The second bimetal switch 12 continues the open state by receiving the heat of the restarted arc tube, and the pulse stop resistor 10
The state which disconnected is maintained.

Next, the starter portion of the metal halide lamp having the structure shown in the above embodiment, that is, the first bimetal switch 5, the nonlinear ceramic capacitor 6, the current damper 7, the semiconductor switch 8, the phase stabilizing resistor 9, a starter portion including the pulse stopping resistor 10, the second bimetal switch 12, and the deterioration preventing resistor 13 is held in a container in a nitrogen gas atmosphere supposed to be in the outer sphere.
The pulse stop function was measured when an AC voltage of 200 V, 50 Hz was applied through a ballast for a 00 W mercury discharge lamp. As a result, all of the experimental starters closed the first and second bimetal switches. The state was maintained, and the results shown in Table 1 were obtained as to the time until the stop of the pulse generation, and it was confirmed that all the devices functioned normally.

[0020]

[Table 1]

Further, 20 prototypes of the metal halide lamps having the structure shown in the above embodiment were produced, and the restart time was measured for the prototype lamps. The results shown in Table 2 were obtained. Was confirmed to have good restart performance.

[0022]

[Table 2]

[0023]

As described above with reference to the embodiments, according to the present invention, in a metal halide lamp having a built-in starter including a nonlinear ceramic capacitor having a pulse stop function, the temperature of the nonlinear ceramic capacitor is reduced. A pulse stop resistor that can be heated to a temperature is connected via a second bimetal switch, and a restart operation is performed with the pulse stop resistor separated by the second bimetal switch. Therefore, the restart performance can be improved while maintaining the pulse stop function at the time of normal startup.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of a metal halide lamp with a built-in starter according to the present invention.

FIG. 2 is a circuit configuration diagram showing a configuration example of a conventional metal halide lamp incorporating a starter having a non-linear ceramic capacitor.

FIG. 3 is a circuit diagram showing a conventional metal halide lamp obtained by improving the conventional example shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arc tube 2a, 2b Main electrode 3 Auxiliary electrode 4 Starting auxiliary resistor 5 First bimetal switch 6 Nonlinear ceramic capacitor 7 Current damper 8 Semiconductor switch 9 Phase stabilizing resistor 10 Pulse stopping resistor 11 Outer sphere 12 2 Bimetallic switches 13 Non-linear ceramic capacitor deterioration prevention resistor 21 Ballast 22 AC power supply

Claims (1)

[Claims] A first and a second main electrode are respectively sealed to the end of a quartz tube, and an auxiliary electrode is sealed at least in proximity to the second main electrode, and a metal halide together with a starting auxiliary gas is sealed therein. A starting circuit, comprising a sealed arc tube, at least a first bimetal switch, a non-linear ceramic capacitor and a semiconductor switch connected in series, connected between first and second main electrodes of the arc tube; A starting auxiliary resistor connected between the connection point of the bimetal switch and the nonlinear ceramic capacitor and the auxiliary electrode, and a pulse capable of heating at least the temperature of the nonlinear ceramic capacitor connected in parallel to the nonlinear ceramic capacitor to the Curie temperature A series circuit of a stopping resistor and a second bimetal switch, at least in parallel with the non-linear ceramic capacitor; The connected resistor for preventing deterioration of the nonlinear ceramic capacitor is housed in an outer sphere filled with an inert gas, and the first and second bimetallic switches are closed at the time of start-up. The first bimetal switch is sometimes opened, and at the time of restart after the light is turned off, the first bimetal switch is closed before the second bimetal switch is closed, so that the first bimetal switch is restarted with the pulse stop resistor disconnected. A metal halide lamp with a built-in starter, characterized in that: