JPS58198897A - Emergency lamp device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an emergency light, and more particularly to an emergency light device that maintains lighting by switching from a commercial power source to a battery power source in an emergency. .

In general, emergency lights have a structure that turns them on both in normal times and in emergencies. Normally, the emergency lights are turned on and the battery, which is the power source in an emergency, is charged. In an emergency when commercial power is cut off, the battery can be used as a power source.
Drive the inverter to continue lighting. On the other hand, the discharge lamps used in such emergency lighting devices usually do not have a long lifespan, so they may burn out before being replaced, and may also come off due to vibration or the like. However, conventional emergency lighting devices drive the DC-AC inverter when the commercial power supply is cut off, regardless of whether a discharge lamp is installed or not, so the inverter generates high-frequency oscillation even when no load is connected during an emergency or inspection. There were times when I did This wastes battery power and furthermore, D
This has the disadvantage that the oscillation output terminal of the C-AC inverter becomes a no-load high voltage, which threatens insulation and increases stress on each component.

This invention was made in view of the above circumstances.In an emergency when the electric discharge lamp burns out or comes off, and commercial power is cut off, this invention not only eliminates wasted battery power, but also improves voltage resistance and reliability. The purpose of the present invention is to provide an emergency lighting device that is smaller in size by lowering the design lower limit value of the device and has reduced production costs.

To summarize this invention, a high frequency current detection section is provided in the high frequency output section of the DC-AC inverter circuit, a timer circuit that starts after the commercial power supply is turned off is built into the charging and inverter control circuit, and after the set time of the timer circuit has elapsed, When a high-frequency current is detected by the high-frequency current detection circuit, the switching element for voltage supply to the inverter provided in the charging/inverter control circuit is kept ON, and when no high-frequency current is detected, the switching element is turned on. The present invention is characterized in that it is provided with a switch element control section that turns off the switch.

Embodiments of the present invention will be described below with reference to the drawings.

The figure is a circuit diagram of an emergency lighting device that is an embodiment of the present invention.

In the figure, a commercial power source 1 is connected to a discharge lamp circuit 2 via a constant blinking switch 4 and to a charging/inverter control circuit 3 via a check switch 5. The discharge lamp circuit 2 includes a discharge lamp 20° ballast Ll, a glow lamp 21. High frequency current interrupting inductor L2. This is a known circuit composed of a triac 22 for controlling commercial voltage.

The charging/inverter control circuit 3 includes a step-down transformer 30. Aftermath rectifier bridge 31. Transistor Tr 1° switch element control unit 32, which is a switch element for supplying voltage to a DC-AC inverter to be described later. Consists of battery B.

The switch element control section 32 includes diodes Di, D2, a capacitor crt, a transistor Tr2 . Try,
Tr4゜Tr5 and resistors R1, R2, R3, R4, R
5, R6, and a timer circuit 40. The cathodes of the diodes Di and D2 are connected to the bases of transistors Tri and Tr2 whose emitters are connected, and also to a capacitor C1 and a resistor R1. The collector of the transistor Tr2 is connected to the negative terminal of the battery B via resistors R2 and R8, and is also connected to the resistor R4 connected to the collector of the transistor Tr8 and the base of the transistor Tr4. A timer circuit 40 is also connected between the collector of the transistor Tr2 and the base of the transistor Tr8.

The timer circuit 40 includes a Zener diode Dz, PUT4
1. A known circuit consisting of capacitor C2, resistors R7 and R8, and the setting time is determined by the capacitance of capacitor C2 and resistor R8.
determined by the resistance value of The transistor Tr5 is
A resistor R6 is connected between the base and emitter, and the collector is connected to a resistor R5 connected to the base of the transistor Tri.

Further, the charging/inverter control circuit 3 is connected to a high frequency preheating current detection circuit 6 and a DC-AC inverter circuit 7. The DC-AC inverter circuit 7 includes an oscillation transformer 70
．． Push-pull connected transistor Tr6. Tr
7. This is a known push-pull inverter circuit composed of resistors RIO and R11.

The high frequency output section of the oscillation transformer 70 is connected to the discharge lamp 20 via high frequency current limiting capacitors CB and C4 and the detection transformer 60 of the high frequency preheating current detection section 6.

The high-frequency preheating current detection unit 6 includes a full-wave rectifier bridge 61. Capacitor C5, resistor R1
It is constructed by connecting a full-wave rectifying and smoothing circuit consisting of 2 and R18.

Next, the operation of the emergency lighting device having the above configuration will be explained.

First, under normal conditions, the discharge lamp 20 is lit because the commercial power source 1 is supplied, and the step-down transformer 30 is connected to the battery B. Full wave rectifier bridge 31. A charging voltage is applied via a resistor R9. At this time, the transistor Tri, which is a switching element that selects whether or not to apply the voltage of the battery B to the DC-AC inverter circuit 7, is turned OFF because the difference between the emitter voltage and the base voltage applied via the diodes Di and D2 is small. are doing. Also,
In the switch element control section 32, only the capacitor CI is charged and current flows through the resistor R1, and all other elements are turned off.

Next, in an emergency when the commercial power supply 1 is cut off, the transistor Tr1. Lower the base voltage of Tr2 together,
Turn on transistors Tri and Tr2. When the transistor Tri is turned on, the voltage of the battery B is supplied to the inverter circuit 7, and the output transformer 70 outputs a high frequency voltage to the discharge lamp 20. Further, when the transistor Tr2 is turned on, a current flows through the charging path of the capacitor C2 and the resistor R8 connected in series, and the timer circuit 40 is driven. Then, the transistor Tr4 is also turned on to turn on the transistor Tri. On the other hand, when charging of capacitor C2 progresses and its charging voltage reaches the Zener voltage of Zener diode Dz, Zener diode D becomes conductive and PUT41
turns on. As a result, transistor +r3 is turned on and one transistor Tr4 is turned off. Note that the time from the cutoff of the commercial power supply 1 to the turn-off of the transistor Tr4 is set to about 1 second in this embodiment.

As a result of the above operation, when the commercial power supply is turned off, the transistor Tri is turned on for about one second, and then the transistor Tr4 is turned off, but the DC-AC inverter circuit 7 is unconditionally driven during that one second. When the discharge lamp 20 is attached, a high-frequency preheating current i flows to the output side. Then, the high frequency preheating current detection circuit 6 immediately detects the current i, full-wave rectifies the detected current, smoothes it, and applies it to the transistor Tr5. That is,
When high-frequency preheating current i flows, transistor Tr5 turns on.
L, T turns on the transistor Tri regardless of whether the transistor Tr4 is on or off.

As a result, the voltage of the battery B continues to be supplied to the DC-AC inverter circuit 7 via the transistor Tri, so that the discharge lamp 20 remains lit.

However, if the commercial power supply 1 is cut off while the discharge lamp 20 is burnt out or removed or not attached, the detection circuit 6 does not detect the high-frequency preheating current i during the above-mentioned 1 second. As a result, the transistor Tr5 is ONL. After all, in this case, the inverter circuit 7 is driven for about 1 second after the commercial power supply 1 is turned off, but stops operating after 1 second has elapsed.

As described above, when the discharge lamp is in a normal operating condition, the battery will turn on normally in an emergency, and if the discharge lamp is disconnected or burnt out and is not operating normally, the inverter will operate normally in an emergency. will be stopped.

Note that the constant blinking switch 4 is used when the discharge lamp 4 is not intentionally turned on using the commercial power source 1. The inspection switch 5 is
It is used to forcibly cut off the commercial power supply 1 and confirm emergency operation.

Furthermore, in this embodiment, the high-frequency preheating current detection circuit 6 detects the high-frequency preheating current and turns on the transistor Tri, but the detection target may be the high-frequency current that is the idle current of the discharge lamp 20.

In that case, a high-frequency current detection section is provided on the capacitor C, and the timer circuit 40 is set to several seconds until the discharge starts.

As described above, according to the present invention, a charging/inverter control circuit having a switch element that controls voltage supply to an inverter circuit is provided with a switch element control section having a built-in timer circuit, and a high frequency current detection circuit detects a high frequency current. When a discharge lamp is detected, the switch element is turned on, and when it is not detected, it is turned off, so the inverter circuit does not operate when there is no load and no discharge lamp is installed. As a result, the lower design limits for voltage resistance and reliability of the oscillation transformer etc. can be lowered, and the production cost of the emergency lighting device can be significantly reduced. Furthermore, since there is no oscillation when there is no load, it is possible to prevent wastage of battery power.

[Brief explanation of drawings]

The figure is a circuit diagram of an emergency lighting device that is an embodiment of the present invention. 2...Discharge lamp circuit, 3...Charging and ear/'4-
JI control circuit, 6... High frequency preheating current detection circuit, 7... DC-AC inverter circuit, 20... Discharge lamp, 32... Switch element control section, 4
0...Timer circuit, Trl...Switch element (transistor).

Claims (1)

[Claims] (1) It has a discharge lamp circuit connected to a commercial power source, a DC-AC inverter circuit that applies a high frequency voltage to the discharge lamp and is driven by a battery, and a charging circuit for the battery, and a voltage from the battery to the inverter circuit. A charging/inverter control circuit having a switch element for controlling supply is provided, and in an emergency when the commercial power supply is turned off, the discharge lamp is
- In an emergency lighting device that lights up using the high frequency voltage of an AC inverter circuit, a high frequency current detection section is provided in the high frequency output section of the DC-AC inverter circuit, and a timer circuit that starts after the commercial power supply is turned off is provided in the charging and inverter control circuit. Further, after the set time of the timer circuit has elapsed, the high-frequency current detection section keeps the switch element ON when a high-frequency current is detected in the path, and turns the switch element ON when the high-frequency current is not detected. An emergency lighting device comprising a switch element control section that turns off the emergency lighting device.