JP2937711B2 - Discharge lamp lighting device and emergency light device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention reduces the number of terminals of an inverter and protects the inverter circuit when the discharge lamp is discharged on one side or when a filament is broken while maintaining the startability of the discharge lamp. The present invention relates to a discharge lamp lighting device and an emergency light device using the discharge lamp lighting device.

[0002]

2. Description of the Related Art In an emergency lamp device, a device using an inverter circuit has been put into practical use as a discharge lamp lighting device for lighting a fluorescent lamp (discharge lamp) in an emergency. 4 and 5 show circuit diagrams of a conventional discharge lamp lighting device of an inverter circuit type. Here, the electrode of the fluorescent lamp is composed of a filament that heats the electrode by a preheating current, and an emitter that is provided on the front surface of the filament and is made of a metal having excellent electron emission properties. A device that provides a discharge winding and a preheating winding as the secondary winding of the output transformer of the inverter, and applies the voltage of the discharge winding to the emitter to discharge while heating the filament with the preheating winding. is there. Here, FIG. 4 shows a circuit for preheating on one side, and FIG. 5 shows a circuit for preheating on both sides. The capacitor inserted between the output transformer and the fluorescent lamp is a ballast capacitor for limiting current.

[0003]

However, in the lighting device of the above-mentioned method, since a preheating winding is required in addition to the discharging winding, there is a disadvantage that the number of terminals increases and the output transformer becomes large. Further, since the preheating current always flows through the filament even during lighting, there is a disadvantage that power loss is large and efficiency is low.

Further, an emitter for emitting electrons may be removed while a fluorescent lamp is being used, and a state where discharge cannot be performed normally (emireless state) may occur. If only one of the two electrodes is removed,
One half-wave normally discharges, but the other half-wave has a one-sided Emiless state in which normal discharge does not occur. If the one-sided Emiless state continues, the output transformer of the inverter is magnetized and a large current flows to the primary side, and the transistor may be overheated and damaged. In order to prevent this, in the conventional discharge lamp lighting device, as shown in FIGS.
A choke coil of about mH was inserted to allow the reverse half-wave current to escape. For this reason, there is a disadvantage that the number of parts increases.

According to the present invention, the number of terminals of the inverter can be reduced and the number of parts can be reduced.
It is an object of the present invention to provide a discharge lamp lighting device and an emergency light device using the same, which can improve the power efficiency and protect the inverter circuit when the discharge lamp is discharged on one side or when the filament is broken.

[0006]

SUMMARY OF THE INVENTION The invention of claim 1 of the present application is directed to a two-element system having a filament and an emitter.
In a discharge lamp lighting device for lighting a discharge lamp having two electrodes, an inverter is connected between one terminal of both filaments, and a secondary coil and a capacitor of a transformer are connected in parallel between the other terminals of the two filaments. And a primary coil and a transistor of the transformer.
And a DC power supply were connected in series.

According to a second aspect of the present invention, in a discharge lamp lighting device for lighting a discharge lamp having two electrodes each having a filament and an emitter, an inverter is connected between one terminal of both filaments. A series circuit of a secondary coil , a capacitor and a resistor of a transformer connected in parallel is connected between the other terminals of the two filaments, and a primary coil of the transformer is further connected.
, A transistor and a DC power supply were connected in series.

[0008] The invention of claim 3 of this application was connected a resistor in parallel with each of the two filaments.

The invention of claim 4 of the present application is directed to claims 1 to
Emergency using the discharge lamp lighting device described in any of 3 above
A lighting apparatus, a power failure detection signal, and a switching換手stage connecting switching the electrode of the discharge lamp to the commercial power supply side or the inverter side.

[0010]

First, before referring to FIG.
The proposed discharge lamp lighting device will be described. Discharge lamp 1
An inverter 2 is connected between one terminal 1aa of the filament of one electrode 1a and one terminal 1ba of the filament of the other electrode 1b, and a terminal on the opposite side of the filament of one electrode 1a of the discharge lamp. The choke coil 3 and the capacitor 4 were connected between 1ab and the terminal 1bb on the other side of the filament of the other electrode 1b.
Immediately after the inverter starts operating and outputs a voltage, the discharge lamp 1 does not discharge, so the inverter 2 → the filament 1a
A current flows through the path of the capacitor 4, the filament 1b, and the inverter 2. That is, the filaments 1a and 1b can be first preheated by the discharge voltage. When the filaments 1a and 1b are preheated, first, discharge starts from one of the filaments (half-wave discharge state). Assuming that the discharge is started from the filament 1a side, the half wave to be discharged includes the inverter 2 → the filament 1a
A current flows through the path of → filament 1b → inverter 2, and at the time of reverse half-wave, a current flows through the path of inverter 2 → filament 1b → choke coil 3 → filament 1a → inverter 2. The current flows through the choke coil 3 because the oscillation frequency of the inverter 2 is extremely reduced during the reverse half-wave in the half-wave discharge state (for example, 100 kHz → 2
5 kHz). Thereby, the heating of the inverter 2 is prevented. After this half-wave discharge has continued for a certain period of time (about 2 to 3 seconds), discharge is started from both electrodes to light up normally. After normal lighting, the impedance between the electrodes 1a and 1b decreases, so that current flows through the path of the inverter 2, the filament 1a, the filament 1b, and the inverter 2, and almost no current flows through the choke coil 3.

When the discharge lamp is a one-sided Emiless lamp (for example, the electrode 1b is Emiless) and is in a half-wave discharge state, the half-wave is also generated at the time of the reverse half-wave (when 1b has a negative polarity) in which no discharge occurs. A current flows through the choke coil 3 on the same principle as in the discharge state. Thereby, overheating damage of the inverter 2 is prevented. As described above, the single output of the inverter 2 is used for both preheating and discharging of the filament, thereby simplifying the configuration and improving power efficiency. Furthermore, by connecting the inverter 2, the choke coil 3, and the capacitor 4 to the terminal on the opposite side of the electrode, the inverter 2 can be protected against a half-wave discharge state of an Emiless lamp or the like. The invention described in claim 1 of the present application
The choke coil 3 shown in FIG.
And the primary coil, transistor and direct
A circuit consisting of a power supply was provided. Turn on this transistor
When current flows through the primary coil, the secondary coil is demagnetized,
The impedance decreases. Thereby, the inverter 2
Current flows through both filaments and the secondary coil of the discharge lamp 1.
Easy to flow through, filament preheats rapidly
Therefore, the discharge lamp 1 can be quickly turned on.
If current easily flows through the secondary coil, the discharge lamp
The transition from preheating to discharging of the lament may be difficult.
You. Therefore, a transistor is used by using a timer switch, etc.
By turning off in a short time, the impedance of the secondary coil
To prevent the above problem,
Lighting is performed quickly. In addition, preheating current is almost
Power flow can improve power efficiency
You.

Also, the secondary coil includes the output of the inverter.
When a direct current component is applied, the iron core is demagnetized and the current easily flows. This is in some cases the transition from the preheating of the filament of the discharge lamp due to the discharge becomes difficult. Therefore,
In the discharge lamp lighting device according to the second aspect , a resistor is connected in series with the secondary coil . When a voltage is applied to this series circuit,
Since the current is limited by the action of the resistor, no DC component voltage is applied to the choke coil, and no demagnetization occurs. This allows the discharge lamp to be turned on more quickly.
It is.

Further, in the discharge lamp lighting device according to the third aspect,
A resistor was connected in parallel with the filament of the discharge lamp. This allows a certain amount of current to flow even when the filament is broken, thereby preventing the inverter from being damaged by heating.

Further, in the emergency light device according to the fourth aspect, the electrode of the discharge lamp is switched to the commercial power supply terminal or the inverter side when the power failure detection signal is generated. When cut place of the inverter side, the discharge lamp is switched to the same discharge lamp lighting device and the upper Symbol configuration. This makes it possible to protect the transistor from overheating while facilitating the starting of the discharge lamp, and to improve the reliability of the emergency lamp.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, referring to FIG.
A description will be given of the discharge lamp lighting device that was the premise. This emergency light device is a device in which a fluorescent lamp FL, which is a discharge lamp, is always lit by a commercial power supply AC in normal times, and is lit by supplying power from an inverter INV when a power failure detection signal is input.
Switching between the commercial power supply AC and the inverter INV is performed by the switching unit 11 to which the power failure detection signal is input and the relay RY. The relay RY is a two-circuit relay, and both terminals of one electrode of the fluorescent lamp FL serving as a discharge lamp are connected to a common contact. The relay RY is normally excited and connected to a normally open contact (commercial power supply side). The normally open contacts of the relay RY are connected to the commercial power source A, respectively.
C and a glow lamp S are connected. The other poles of the commercial power supply AC and the glow lamp S are connected to electrodes on the opposite side of the fluorescent lamp FL.

Further, one normally closed contact of the relay RY has:
The secondary coil t2 of the output transformer T of the inverter INV is connected. The terminal on the opposite side of the secondary coil t2 of the output transformer T is connected to the other electrode of the fluorescent lamp FL. The capacitor inserted between the terminal on the opposite side of the secondary coil t2 of the output transformer T and the other electrode of the fluorescent lamp FL is a ballast capacitor for limiting current.

Further, a bypass circuit is connected to the other normally closed contact of the relay RY. The bypass circuit
The choke coil L1, the capacitor C1, and the resistor R1 connected in parallel are connected in series. Choke coil L
1 is about 250 mH, and the capacitor C1 is 4 mH.
The one having about 70 pF is used. This bypass circuit is for flowing the current of the inverter INV having only the discharge voltage supply terminal through the filament of the fluorescent lamp FL to heat the filament. When the fluorescent lamp FL is in the half-wave discharge state, this circuit bypasses the reverse half-wave current that does not discharge. The half-wave discharge state occurs at the beginning of lighting due to one-side preheating or during the one-side emiless state.

Further, resistors R2 and R3 are connected between the two normally closed contacts of the relay RY and between the electrodes of the fluorescent lamp FL on the opposite side.
Is connected. This resistor is a resistor for bypassing a current that should originally flow through the filament when the filament breaks while the fluorescent lamp is turned on by the inverter INV.

A charging section 12 is connected to the commercial power supply AC. Charging unit 12 is connected to secondary battery 10 via switching unit 11. That is, the charging unit 12 is connected to the commercial power source A
This is a circuit for outputting a DC voltage suitable for charging the secondary battery 10 by step-down rectifying C (100 V).

The switching unit 11 is a circuit for switching the connection of the circuit when the stop (power failure) of the commercial power supply AC is detected. Normally, the secondary battery 10 and the charging unit 12 are connected, and power is not supplied to the inverter INV. When the voltage of the charging unit 12 decreases, it is determined that a power failure has occurred, and the secondary battery 10 is disconnected from the charging unit 12 and connected to the inverter INV.

The primary circuit of the inverter INV includes a primary coil t1 to which transistors Q1 and Q2 are push-pull connected, a feedback coil t3 for oscillation, and a choke coil L for switching the input current of the inverter to the switching section 11 to a constant current.
Two. When the power of the secondary battery 10 is passed through this circuit, the circuit oscillates at a frequency of 50 to 100 kHz. When this high-frequency current is applied to the primary coil of the output transformer T, electric power is generated in the secondary coil t2.

The operation of the emergency light device having the above configuration when a power failure detection signal is input will be described. When the switching unit 11 detects a power failure due to a voltage drop in the charging unit 12, the switching unit 11 stops supplying power to the relay RY and connects the secondary battery 10 to the inverter INV to start operation. The relay RY is de-energized due to the interruption of power supply, and connects the fluorescent lamp FL (common contact) to the inverter INV side (normally closed contact). At the same time, the inverter INV starts oscillating, and the output transformer T
Generates a voltage in the secondary coil t2. This voltage is applied to the fluorescent lamp FL via the relay RY or the like. Fluorescent lamp FL
Does not discharge at first, a current flows through the bypass circuit (particularly, the capacitor C1) through the filament, and the filament is heated. As a result, the electrode of the fluorescent lamp FL is easily discharged, and starts discharging. At the beginning of the discharge, only one of the electrodes is in a half-wave discharge state, but at the time of the reverse half-wave when the fluorescent lamp FL is not discharged, a current flows through the bypass circuit (particularly the choke coil L1) to protect the inverter circuit. . After a half-wave discharge state for a few seconds, discharge is started at both electrodes and a complete lighting state is achieved. At the time of complete lighting, the impedance of the fluorescent lamp FL is extremely reduced, so that almost no current flows in the bypass circuit. At this time, since the bias of the choke coil L1 is prevented by the resistor R, the voltage is easily applied to the fluorescent lamp FL, and the fluorescent lamp FL easily starts high-frequency lighting.

The reason why the current mainly flows through the choke coil L1 during the reverse half-wave of the half-wave discharge state is that the oscillation frequency of the inverter INV decreases from 100 kHz to about 25 kHz in the half-wave discharge state. This is because the impedance of the choke coil L1 becomes lower than the impedance of the capacitor C1.

Also, due to the lack of the emitter of the electrode, etc.
The fluorescent lamp FL may be in a half-wave discharge state, but at the time of the reverse half-wave when the fluorescent lamp FL does not discharge, a current flows through the bypass circuit to protect the inverter circuit. At the time of complete lighting, the impedance of the fluorescent lamp FL is extremely reduced, so that almost no current flows in the bypass circuit.

Further, when the filament of the fluorescent lamp FL is broken, the fluorescent lamp FL is not preheated and discharge cannot be started, and the INV-filament-bypass circuit-
Since the filament-INV circuit is not formed, the transistor of the inverter INV may be heated and damaged. For this reason, the resistors R2 and R3 are connected in parallel to the filament so that a certain amount of current flows even when the filament is broken. If only one of the filament breaks,
The other filament is preheated and lights up although it is in a half-wave discharge state. Thereafter, the emitter on the side where the filament is broken by the heating due to the collision of electrons also starts discharging. In a state where the filament is normally connected, the current flowing through this resistor does not matter because the resistance value of the filament is small.

Hereinafter, the present invention will be described with reference to FIG.
This will be described in detail. According to the present invention, in the inverter lighting circuit of the emergency light device, the current at the time of preheating is increased to quickly start the fluorescent lamp FL . FIG. 3 shows only the inverter lighting circuit extracted from the emergency light device. The same components as those in the circuit of FIG. In this circuit, a transformer comprising a primary coil L5 and a secondary coil L1 'is connected to the other terminal of the fluorescent lamp FL instead of the choke coil L1. On the side of the primary coil L5, a circuit including the primary coil L5, the transistor Q, and the DC power supply E is formed. Transistor Q is to the current flowing through the primary coil L 5 from the DC power source E on. The secondary coil L1 'is generated by this DC current.
Also demagnetize, and the impedance decreases. As a result, the current of the inverter INV easily flows through both filaments of the fluorescent lamp FL and the secondary coil L1 ', and the filament is preheated quickly. When the filament is preheated rapidly, the fluorescent lamp FL is immediately turned on. Therefore, the transistor Q may be turned off in a short time by using a timer switch or the like. By doing so, the fluorescent lamp FL can be quickly turned on without lowering the efficiency of the inverter.

[0027]

As described above, according to the present invention, since both sides of the filament can be preheated and the discharge lamp can be turned on using a single output inverter and a capacitor, the number of parts is small and the size can be reduced. Oh Ru. In addition , in the case of a half-wave discharge, current flows through the secondary coil of the transformer, so that damage to the inverter due to heating can be prevented. In addition, by supplying current to the primary coil when lighting
Because the secondary coil is demagnetized and the impedance decreases,
The current during preheating increases. Therefore, the filament
Preheat quickly, and light the discharge lamp quickly
Can be. On the other hand, if current easily flows through the secondary coil,
It is difficult to transition from preheating to discharging of the lamp filament.
In some cases. So the transistor is a timer switch
To turn off the secondary coil in a short time.
Peedance rises. This prevents the above problem.
And the discharge lamp is turned on quickly.
In addition, since the preheating current hardly flows at the time of lighting, power efficiency
Can be improved.

According to the second aspect of the present invention, it is possible to prevent a start-up failure due to the demagnetization of the choke coil due to a DC component at the time of start-up, and to prevent the discharge lamp from being in a half-emissive state due to a single-sided emiless state. Can also protect the transistor from overheating. Furthermore, by connecting a resistor in parallel with the filament of the discharge lamp, even if the filament is broken, a certain amount of current can continue to flow to the secondary side,
The inverter can be prevented from being destroyed by heating. Also,
By using such a discharge lamp lighting device as an emergency light device, the reliability of the emergency light device can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a discharge lamp device on which the present invention is based .

FIG. 2 is a circuit diagram of an emergency light device on which the present invention is based .

Figure 3 is a circuit diagram showing the structure of the inventions of Example

FIG. 4 is a circuit diagram of a conventional discharge lamp lighting device.

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

[Explanation of symbols]

AC-commercial power supply FL-fluorescent lamp L1-choke coil R1-resistor R2 (connected in series with choke coil) R2,3-resistor (connected in parallel to filament of fluorescent lamp FL) RY-relay 11- Switching section

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁶ , DB name) H05B 41/14 310 H05B 41/24

Claims (4)

(57) [Claims] 1. A discharge lamp lighting device for lighting a discharge lamp including two electrodes each having a filament and an emitter, wherein an inverter is connected between one terminal of the two filaments, and the other terminal of the two filaments is connected between the two terminals. , A secondary coil of a transformer and a capacitor are connected in parallel, and a primary coil, a transistor and a DC power supply of the transformer are connected in series. 2. A discharge lamp lighting device for lighting a discharge lamp provided with two electrodes each having a filament and an emitter, wherein an inverter is connected between one terminal of both filaments and between the other terminal of both filaments. Is connected to a series circuit of a secondary coil, a capacitor, and a resistor of a transformer connected in parallel.
A discharge lamp lighting device in which a secondary coil, a transistor and a DC power supply are connected in series. 3. The discharge lamp lighting device according to claim 2, wherein a resistor is connected in parallel to each of said two filaments. 4. An emergency light device to which the discharge lamp lighting device according to claim 1 is applied, wherein an electrode of the discharge lamp is switched to a commercial power supply or an inverter according to a power failure detection signal. Emergency light device provided with switching means for switching.