JPH06196276A - Discharge lamp lighting device for lighting system - Google Patents

Abstract

PURPOSE:To provide a discharge lamp lighting device capable of being protected from a temperature rise while decreasing the number of part items. CONSTITUTION:When a commercial AC power source E is turned on, pulses are generated by a pulse generating circuit 26, and pulses are repeatedly fed to a discharge lamp HID to light it. After the discharge lamp HID is lighted, the pulse output of the pulse generating circuit 26 is stopped by a pulse control circuit 27. When temperatures of the first and second choke coils L11, L12 rise, the temperature rising speed of the first choke coil L11 is faster than that of the second choke coil L12 because the impedance of the first choke coil L11 is smaller. The discharge lamp HID is made the half-wave discharge state or the short circuit state on the secondary side, and a temperature fuse 24 is blownout when the temperature of the first choke coil L11 rises. This discharge lamp lighting device can be surely protected from the temperature rise by one temperature fuse 24.

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 for protecting a current limiting element when the temperature is above a predetermined value.

[0002]

2. Description of the Related Art In a conventional discharge lamp lighting device of this type, for example, a circuit for lighting a high-pressure metal halide lamp or a high-pressure mercury lamp is provided with a current limiting element. As a result, the temperature of the current limiting element rises. Therefore, a configuration is known in which a plurality of current limiting elements are connected in parallel.

As described above, when a plurality of current limiting devices are connected in parallel, for example, a configuration as shown in FIG. 6 is known.

As shown in FIG. 6, a commercial AC power source E is connected with a fuse F, a first temperature fuse 1 and a second temperature fuse 2 in series, and a first choke coil L1 and a first choke coil L1 serving as a current limiting element are connected. Two choke coils L2 are connected in parallel and connected to the discharge lamp HID. Also a choke coil
A parallel circuit of a resistor R1 and a capacitor C1 is connected between a connection point of the L1 and the choke coil L2 and one end of the commercial AC power source E. The first thermal fuse 1 is brought into contact with the first choke coil L1 and the second thermal fuse 2 is brought into contact with the second choke coil L2 to detect the respective temperatures.

Then, when the temperature of the first choke coil L1 rises, the first thermal fuse 1 is cut off to turn off the discharge lamp HID, and when the temperature of the second choke coil L2 rises, the second thermal fuse 2 Is disconnected and the discharge lamp HI
The D is turned off to prevent heating of the first choke coil L1 or the second choke coil L2.

[0006]

However, as described above, the first thermal fuse 1 is provided for each first choke coil L1, and the second thermal fuse 2 is provided for each second choke coil L2. As described above, providing a temperature fuse for each choke coil increases the number of parts and complicates the circuit configuration.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a discharge lamp lighting device and a lighting device capable of protecting from a temperature rise while reducing the number of components.

[0008]

According to a first aspect of the present invention, there is provided a discharge lamp lighting device, wherein a plurality of current limiting elements are connected in parallel between a discharge lamp and a power source, and the current limiting element is provided in a temperature protection device. In a discharge lamp lighting device that detects the temperature of the current limiting element and protects the current limiting element when the temperature is equal to or higher than a predetermined value, the impedance of the current limiting element is made different, and the current limiting element having the lowest impedance of the current limiting elements is used. The temperature protection device is attached to the element.

A discharge lamp lighting device according to a second aspect of the present invention is the discharge lamp lighting device according to the first aspect, in which a current limiting element is arranged along a longitudinal direction of an elongated cylindrical case body, and the lowest impedance. A current limiting element is disposed on one end side, and the temperature protection device is attached to the side having the current limiting element adjacent to the current limiting element having the lowest impedance.

A lighting device according to a third aspect of the present invention comprises a fixture body,
It is provided with a discharge lamp attached to the fixture body, and the discharge lamp lighting device according to claim 1 for lighting the discharge lamp.

[0011]

In the discharge lamp lighting device according to the present invention, the impedance of the current limiting element connected in parallel is made different, and the temperature limiting device is attached to the current limiting element having the lowest impedance, so that the most current limiting element is installed. Since the temperature protection device is attached to the current limiting element whose temperature rises, the entire current limiting element can be protected from temperature rise with a small number of temperature protection devices.

A discharge lamp lighting device according to a second aspect of the present invention is the discharge lamp lighting device according to the first aspect, in which a current limiting element having the lowest impedance is disposed at one end side of the elongated cylindrical case body, and the current limiting device is provided. Since the temperature protection device is attached to the side of the element that has the current limiting device adjacent to it, the temperature protection device is attached to the position where the temperature rises most, and the temperature protection device can be reliably protected from temperature rise with a small number of temperature protection devices.

A lighting device according to a third aspect of the present invention is the discharge lamp lighting device according to the first aspect, in which all the current limiting elements are heated by a small number of temperature protection devices in order to turn on the discharge lamp attached to the fixture body. Can protect against climbs.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the illumination device of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, 11 is a fixture main body of the projector, and the fixture main body 11 has a fixture 12 to be attached to a surface to be attached, and the fixture 12 has an opening 13 on the entire surface. It has a bowl-shaped reflector 14, and a discharge lamp HID such as a 2000 W high pressure metal halide lamp or a high pressure mercury lamp is attached to the inner surface side of the reflector 14.

A discharge lamp lighting unit 15 as shown in FIG. 3 is built in or connected to the instrument body 11.

In this discharge lamp lighting unit 15, an obstructing upper lid 22 is fitted and attached to one end of an elongated tubular case body 21, and the upper lid 22 side of the case body 21 serves as a current limiting element. The first choke coil L11 and the second choke coil L12 having a higher impedance than the first choke coil L11 are housed, and the power factor correction capacitor C1 is further provided.
1 and a resistor R11 are housed, and a resin 23 such as an unsaturated polyester compound is filled around the first choke coil L11, the second choke coil L12 and the power factor improving capacitor C11.

The second choke coil L11 is connected to the second choke coil L11.
A temperature fuse 24 as a temperature protection device is attached to the choke coil L12 side of. Since the temperature of this portion becomes the highest, the temperature rise can be detected most reliably.

A lower lid 25 is attached to the other end of the case body 21, a part of a pulse generating circuit 26 is attached to the lower lid 25, and a fuse F is also attached.

Next, a specific circuit will be described with reference to FIG.

As shown in FIG. 1, a discharge lamp lighting unit 15 is connected to the commercial AC power source E, and a discharge lamp HID is connected to the discharge lamp lighting unit 15.

Further, the discharge lamp lighting unit 15 is connected to a temperature fuse 24 via a fuse F, and this temperature fuse 24 is commercialized via a parallel circuit of a first choke coil L11 and a second choke coil L12. It is connected to the AC power supply E.

Further, a resistor R12 and capacitors C12 and C13 are connected in parallel between the terminals via a fuse F,
Also, a series circuit of a capacitor C14, a resistor R13 and a resistor R14 is connected.

A pulse control circuit 27 is connected to the resistor R14. In this pulse control circuit 27, the input terminal of the full-wave rectifier 28 is connected between both terminals of the resistor R14, the capacitor C15 is connected between the output terminals of this full-wave rectifier 28, and the capacitor C15 is connected in parallel with this capacitor C15. Resistor R15, resistor
The parallel circuit of R16 and capacitor C16 and resistor R17 is connected. In addition, the full-wave rectifier 28 via the resistor R15 is connected to the light-emitting diode LED11 and the thyristor Th.
11 are connected in series. Also, this thyristor Th11
The gate of the resistor R18, the resistor R19 and the constant voltage element Tr
i11 is connected.

On the other hand, the first and second choke coils L1
The pulse generation circuit 26 including 1 and L12 is provided between the terminals of the commercial AC power source E via the fuse F and the temperature fuse 24,
A parallel circuit of coil L14, power factor correction capacitor C11 and resistor R11, coil L15 and triac Tri12 are connected in series, and resistor R20 is connected in parallel to the discharge lamp HID.
The series circuit of resistor R21 and capacitor C17 is connected. In addition, the Triac Tri12 gate has a resistor
R22, triac Tri13, constant voltage element TNR11, phototriac FT13, resistor R23, capacitor C18 and resistor R24 are connected.

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

First, when the commercial AC power source E is turned on, a voltage is applied to the discharge lamp HID via the temperature fuse 24, the first choke coil L11 and the second choke coil L12. When a voltage is applied to the resistor R14, it is full-wave rectified by the full-wave rectifier 28 and charged in the capacitor C15, but since no voltage is applied to the gate of the thyristor Th11, the thyristor Th11 does not turn on and emits light. Diode LED11
Keeps the off state. Thus, the light emitting diode LE
Since the D11 remains off, the Phototriac FT
11 remains off.

On the other hand, the AC from the commercial AC power source E is the first
Choke coil L11 and second choke coil L12
When a current flows through the series circuit of resistor R20, resistor R21 and capacitor C17 via, and the capacitor C17 is charged, the resistor R20, resistor R21 and capacitor C1
Apply a voltage to the constant voltage element TNR11 according to the time constant of 7.
Turn on the triac Tri13, apply voltage to the gate of the triac Tri12, and turn on the triac Tri12.

When the triac Tri12 is turned on, the electric charge stored in the power factor correction capacitor C11 is changed to the coil.
Through the L14, the first choke coil L11 and the second choke coil L12, the voltage is boosted by the turn ratio of the second choke coil L12 and the coil L13, and is repeatedly applied to the discharge lamp HID.

Then, the discharge lamp HID is turned on.

In consideration of the time when the discharge lamp HID can be lit sufficiently reliably, the capacitor C16 is charged, the triac Tri11 is turned on, and the thyristor Th11 is turned on to turn on the light emitting diode LED11. By turning on the light emitting diode LED11, the photo triac FT
11 turns on and does not turn on triac Tri13, keeps triac Tri12 off and stops pulse output.

As mentioned above, the first choke coil L11
By dividing the current limiting element into two, the second choke coil L12 and the second choke coil L12, the total length of the coil becomes shorter than that in the case of one coil, the magnetic coupling to the coil L13 becomes more complete, and a stable pulse is obtained. In addition, the capacity of the power factor correction capacitor C11 can be reduced.

Further, the temperature rise of the first choke coil L11 and the second choke coil L12 means that the impedance of the first choke coil L11 is the second choke coil L1.
Since the first choke coil L11 is faster than the second choke coil L12, as shown in FIGS. 3a and 3b, for example, the discharge lamp HID is Even in the half-wave discharge state or the secondary side short-circuit state, one temperature fuse 24 can surely protect from the temperature rise.

As shown in FIG. 5, the single winding transformer 31
The same effect can be obtained when the first choke coil L11 and the second choke coil L12 are connected in the middle.

[0035]

According to the discharge lamp lighting device of the first aspect, the impedance of the current limiting element connected in parallel is made different, and the temperature limiting device is attached to the current limiting element having the lowest impedance, thereby limiting the current. Since the temperature protection element is attached to the current limiting element having the highest temperature rise, the entire current limiting element can be protected from the temperature rise with a small number of temperature protection devices.

According to the discharge lamp lighting device of the second aspect,
In addition to the discharge lamp lighting device according to claim 1, a current limiting element having the lowest impedance is disposed on one end side of an elongated tubular case body, and the temperature limiting element is provided on the side having the current limiting element adjacent to the current limiting element. Since the protection device is attached, the temperature protection device is attached at the position where the temperature rises the most, and it is possible to reliably protect from the temperature rise with a small number of temperature protection devices.

According to the lighting device of the third aspect, in the discharge lamp lighting device according to the first aspect, since the discharge lamp attached to the main body of the fixture is turned on, the temperature of the entire current limiting element is raised with a small temperature protection device. Can be protected from

[Brief description of drawings]

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

FIG. 2 is a perspective view showing the outer appearance of the above lighting device.

FIG. 3 is a cross-sectional view showing the same discharge lamp lighting unit as above.

FIG. 4 is a graph showing the temperature rise of the first choke coil and the second choke coil of the same.

FIG. 5 is a circuit diagram showing a discharge lamp lighting device according to another embodiment.

FIG. 6 is a circuit diagram showing a conventional discharge lamp lighting device.

[Explanation of symbols]

 21 Case body 24 Thermal fuse as temperature protection device E Commercial AC power supply HID Discharge lamp L11 First choke coil as current limiting element L12 Second choke coil as current limiting element

Claims (3)

[Claims] 1. A plurality of current limiting elements are connected in parallel between a discharge lamp and a power source, and the temperature of the current limiting element is detected by a temperature protection device, and when the temperature exceeds a predetermined value. In the discharge lamp lighting device for protecting the current limiting element, the impedance of the current limiting element is made different, and the temperature protection device is attached to the current limiting element having the lowest impedance among the current limiting elements. Electric lighting device. 2. A current limiting element is arranged along the longitudinal direction of an elongated tubular case body, and the current limiting element having the lowest impedance is disposed at one end side, and the current limiting element having the lowest impedance is provided. The discharge lamp lighting device according to claim 1, wherein the temperature protection device is attached to a side having a current limiting element adjacent thereto. 3. A lighting device comprising: a fixture main body; a discharge lamp attached to the fixture main body; and a discharge lamp lighting device according to claim 1, which lights the discharge lamp.