JPS6412078B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a discharge lamp starting device.

Conventionally, glow lighting tubes have been used to start discharge lamps such as fluorescent lamps, but glow lighting tubes require a long time to complete starting of the discharge lamp after the power is turned on, and It is very unsightly that one blink will almost never lead to the start lighting, and it will start after opening and closing several times.

In addition, instead of the above-mentioned glow flashing tubes, so-called electronic starters using semiconductor switch elements such as thyristors, pulse transformers, or oscillating boosted voltage using capacitors have been proposed, but these are far superior to the above-mentioned glow lighting tubes. Although they can start quickly and smoothly without flickering or blinking, they tend to be very expensive and bulky.

The present invention was made in view of the above points, and its purpose is to be able to start faster than conventional glow lighting tubes, to blink, to start smoothly, and to be compact. The object of the present invention is to realize and provide a discharge lamp starting device that is cheaper than an electronic starter.

FIG. 1 shows a thermal switch type discharge lamp starting device that has already been filed and is the basis of the present invention.

FIG. 2 is a detailed diagram of the thermal switch section used in FIG. 1, and FIGS. 3A to 3C show operating waveforms of the circuit in FIG. 1.

The configuration of the basic circuit in Figure 1 is as follows: A series circuit of an inductive ballast 1 and a discharge lamp 2 is connected to a commercial power supply V _S , and a normally closed thermal circuit is connected to the non-power supply side filament of the discharge lamp 2 in parallel with the discharge lamp. Switch 3 and main heater 11
connect the series circuit and the discharge lamp lighting determination circuit 5,
The main switch element 3 detects the lighting state of the discharge lamp 2.
A holding heater 10 is provided to maintain the operation.

A separately provided heater 20' is a welcome heater that operates in the opposite manner to the holding heater 10.

FIG. 2 shows the structure of the thermal switch 3 and each heater 11, 10, 20'. A main bimetal 3a and an auxiliary bimetal 3b each fixed to terminals 23 and 24 provided on a base 25 are arranged facing each other,
Contact points 26, 26', etc. are provided at the tip, and
The main bimetal 3a is provided with a main heater 11 and a holding heater 10, and the auxiliary bimetal 3b is provided with a welcome heater 20'. In FIG. 2, Figure A shows the normally closed state before the power switch is turned on, and Figure B shows the open state while the lamp is on.

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

In Fig. 3, by applying the commercial power supply V _S at time t ₁ , the inductive ballast 1, the filament F ₁ of the discharge lamp 2, the terminal a, the normally closed thermal switch 3, the main heater 11, the terminal b, and the filament _F2
A preheating current flows through the discharge lamp 2 and heats both filaments F ₁ and F ₂ of the discharge lamp 2 . Figure 3 A shows terminals a and b.
voltage ν _la , b indicates the operation of the main heater 11, and c indicates the operating state of the holding heater 10.

The preheating current flowing through the main heater 11 heats the main bimetal shown in _FIG .
6' is opened, and the discharge lamp 2 lights up due to the generation of a kick voltage V _P due to the inductance of the ballast 1.
As a result, the voltage across terminals a and b is t ₂ in Figure 3 A.
The lighting waveform becomes as shown between ~ _t4 , and the constant voltage diode 19,
The transistor 21 is turned off, and inverted, the transistor 22 is turned on, turning on the holding heater 10, keeping the thermal switch 3 open, and continuing the lighting state.

If lighting of the discharge lamp 2 fails, the voltage between terminals a and b rises to around the power supply voltage, exceeds the threshold of the constant voltage diode 19, and the voltage between the terminals a and b rises to the voltage of the transistor 2.
1, a base current flows through the second heater 20', turns on the welcome heater 20', opens the holding heater 10, and turns on the second heater 20'.
From the state shown in Figure B, the main bimetal 3a cools and moves in the direction of returning to its original state (in the direction opposite to This causes the contacts 26, 26' to close, entering the initial preheating state and repeating the starting operation. (The welcome heater 20' speeds up the contact reclosing.) The starter having the above configuration has the following drawbacks.

(a) Two heaters, the main heater 11 and the holding heater 10, are required for the main bimetal, and the holding heater 10
(b) This results in a large size and high cost; (c) A large preheating current flows through the main heater 11, so a relatively thick heater is required, and the hard bimetal may deform. In addition, processing the lead wires at the heater terminals is difficult due to the large current.

The present invention improves the above-mentioned drawbacks, and provides (a) quick starting of a discharge lamp, (b) elimination of the unsightly flickering caused by failure of starting as in glow lamp tubes, and (c) main features. The purpose of this invention is to reduce the number of bimetal heaters in a thermal switch used as a switch element by one, simplify the circuit configuration, and make it inexpensive.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 4 shows an embodiment of the present invention. A series circuit of a diode 12 and a normally closed thermal switch 3 is provided between the non-power terminals a and b of the discharge lamp 2, a main heater 13 is connected in parallel with the diode 12, an impedance 14 is connected in parallel with the thermal switch 3, and A discharge lamp lighting discrimination circuit 5 is connected in parallel with the thermal switch 3, and an auxiliary heater (for follow-up) 20 is provided in the output circuit of the lighting discrimination circuit 5.

Next, the operation will be explained.

When power supply voltage is applied, ballast 1, filament F ₁ of discharge lamp 2, terminal a, diode 12, normally closed thermal switch 3, terminal b, filament
A preheating current flows through _F2 . FIG. 7 shows operating waveforms in the basic circuit of FIG. 4. A preheating current i shown by a dashed-dotted line flows from time t ₁ at the zero point of the power supply voltage waveform ν _S. Even if the power supply voltage waveform ν _S reaches the next zero point at time t ₂ , the preheating current i is delayed by the inductance of the ballast 1 and becomes 0 at time t ₃ . Due to the action of diode 12, no preheating current flows in the reverse direction, and at time t ₃
A voltage waveform ν _D shown by a solid line appears between terminals a and b, and a voltage waveform ν D shown by a solid line appears between both ends of diode 12, that is, heater 1
Appears between both terminals of 3.

FIG. 6 shows a configuration diagram of a thermal switch used in the apparatus of the present invention, in which 13 indicates a main heater and 20 indicates a follow-up auxiliary heater. A shows the thermal switch in a normally closed state immediately after the power supply voltage is applied.

A main bimetal 3a and an auxiliary bimetal 3b fixed to terminals 23 and 24 provided on the base 25 are arranged facing each other, and contacts 26 and 26' are provided at the tips of the main bimetal 3a.
An auxiliary heater 20 is provided on the auxiliary bimetal 3b.
This shows a configuration with .

The main heater 13 generates heat due to the voltage ν _D between both terminals,
The main bimetal 3a is heated and deformed, and at time _t2 after preheating for a certain period of time, the contact 26 opens from 26' (moves in the direction of arrow X), and the induction kick voltage of the ballast 1 is applied between both electrodes of the discharge lamp. , the discharge lamp 2 is started and lit.

When the discharge lamp 2 is turned on, the voltage between the terminals a and b decreases, and the auxiliary heater 20 is opened by the action of the discharge lamp lighting determination circuit 5. Therefore, the impedance 14 and the main A current flows through the path leading to the terminal a via the heater 13, but due to the action of the impedance 14, this current is lower than the current during preheating, and this current flows through both bimetal 3.
The current is required to keep the contacts 26 and 26' of contacts a and 3b open.

When the discharge lamp 2 fails to start, the auxiliary heater 20 is turned on by the action of the discharge lamp lighting determination circuit 5, and the auxiliary bimetal 3b is turned on as shown in FIG.
is strongly heated and deforms toward the main bimetal 3a (moves in the direction of arrow Y), and after a short time, the contact 26,
26' is reclosed, the preheating current flows again, and the first operation is repeated.

FIG. 5 shows a circuit diagram of another embodiment of the present invention.

The discharge lamp lighting determination circuit 5 includes resistors 17 and 18 for voltage division, and a constant voltage diode 1 for voltage comparison.
9. A transistor 21 whose base and emitter are connected via the constant voltage diode 19, and an auxiliary heater 2 connected to the collector terminal of the transistor 21.
0 and is connected in parallel with the thermal switch 3.

When the discharge lamp 2 starts and lights up, the base current of the transistor 21 is cut off via the constant voltage diode 19 due to a voltage drop between terminals a and b, and the auxiliary heater 20 is opened, and conversely, the discharge lamp 2 fails to start. In this case, a base current flows through the transistor 21 through the constant voltage diode 19 due to an increase in the voltage between the terminals a and b, and the auxiliary heater 20 generates heat, leading to reheating as in the basic circuit of FIG. 4.

FIG. 8 shows another embodiment of the invention. A resistor 27 and a constant voltage diode 29 are added to the circuit diagram of the embodiment shown in FIG. 5 to protect the transistor 21 from withstanding voltage, and the operation is similar to that of the present invention.

FIG. 9 shows another embodiment of the present invention, in which a diode 16,
It is composed of a series circuit of a constant voltage diode 15 and an auxiliary heater 20, and further includes a diode 12 in series with a resistor 30 as an impedance connected in parallel with the thermal switch 3, and a diode 3 in the opposite direction.
1 is inserted to suppress the current constantly flowing through the resistor 30, reduce power consumption, and prevent the resistor 30 from overheating.

FIG. 10 shows an embodiment in which an auxiliary heater 20 is inserted in parallel with the thermal switch 3, and a two-terminal thyristor such as 3S is connected in series with the whole. After the discharge lamp lights up, 3S becomes open and thermal switch 3
cools, closes, and resets to the initial state. Therefore, the power consumption of the holding heater during lighting is eliminated, and when restarting, the preheating state is immediately entered, and restarting is quick.

In FIG. 11, a glow discharge tube is used instead of a thermal switch, and glow discharge is used instead of an auxiliary heater to heat the engine when starting fails or when restarting.

FIG. 12 shows another embodiment of the present invention,
The operation of this embodiment is such that when the discharge voltage increases, an appropriate current is passed through the follow-up heater 20 to compensate for the holding interval of the thermal switch 3 to be appropriate. To explain in more detail, the main heater 13 and resistor 30 are set so that the contacts can be kept sufficiently open even when the discharge voltage of the lamp decreases, and the threshold voltage of the constant voltage diode 29 is also set as expected. Set to a value near the lowest discharge voltage that can be obtained.

When the discharge voltage increases due to the influence of the lamp ambient temperature, etc., the amount of heat generated by the main heater 13 increases and the bimetal 3a deforms in the direction of increasing the contact distance, but at the same time, the voltage between terminals c and d also increases, and the voltage When the Zener voltage of the constant voltage diode 29 is exceeded, the voltage difference is applied to both ends of the follow-up heater 20, so the follow-up heater also generates heat, and the bimetal 3b is also deformed in the same direction as 3a, so the lamp discharge voltage increases. However, the contact holding interval is kept almost constant. The diode 12 is provided to prevent current from flowing to the follow-up heater 20 during negative cycle voltage.

Since the present invention is configured as described above, (a) the main heater for bimetal heating of the thermal switch and the holding heater can be used together, making it possible to simplify, reduce size, weight, and cost.

(b) Since the main heater is not connected in series to the preheating circuit, but in parallel between the starter terminals, it can be used as a starting device for a discharge lamp, such as a 15-30W starter.

It has the following effects.

[Brief explanation of the drawing]

Figure 1 shows an example of this type of discharge lamp starting device;
Figures A and B are an example of a thermal switch used in the device shown in Figure 1, Figures A to C are explanatory diagrams, Figures 4 and 5 are examples of the present invention, and Figures A to C are examples of the thermal switch used in the device shown in Figure 1. FIG. 7 is an explanatory diagram of a thermal switch used in the present invention and its operation, and FIGS. 8 to 12 show other embodiments of the present invention. DESCRIPTION OF SYMBOLS 1...Ballast, 2...Discharge lamp, 3...Thermal switch, 3a...Main bimetal, 3b...Auxiliary bimetal, 5...Discharge lamp lighting determination circuit, 11...
...Main heater, 12...Diode, 13...Main heater, 14...Impedance, 17, 18...
Resistor, 19... Constant voltage diode, 20... Auxiliary heater for chasing, 20'... Auxiliary heater for meeting, 21... Transistor, 23, 24...
Terminal, 25...Base, 26, 26'...Contact,
27... Resistor, 28... Resistor, 29... Constant voltage diode, 31... Diode.

Claims (1)

[Claims] 1 A series circuit of an inductive ballast and a discharge lamp is connected to a commercial power source, and a main thermally responsive electrode and an auxiliary thermally responsive electrode are provided oppositely between both electrodes on the non-power side of the discharge lamp and have the same bending direction. A normally closed thermal switch including an electrode, and a main heater that is energized by the current flowing through the thermal switch and opens the main electrode from the auxiliary electrode are provided near the main thermally responsive electrode, and when the discharge lamp is started, the main heater is activated. In a discharge lamp starting device that heats the main thermally responsive electrode, opens a thermal switch in a short time, and starts the discharge lamp with a generated kick pulse, a diode is connected in parallel to the main heater, and a current limiting impedance and the main heater are connected in parallel. A series circuit with the heater is connected between the non-power supply side filaments of the discharge lamp, and the impedance is connected in parallel with the thermal switch, thereby supplying current to the main heater while the discharge lamp is lit. The main thermally responsive electrode is self-retained, an auxiliary heater is provided near the auxiliary thermally responsive electrode, and a discharge lamp startup determination circuit is provided, so that when startup fails, etc., the auxiliary heater is activated by the output signal of the startup determination circuit. A discharge lamp starting device characterized in that it generates heat, bends an auxiliary thermally responsive electrode toward the main thermally responsive electrode, recloses a thermal switch, and restarts the lamp.