JPH0451933B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a high-pressure sodium lamp device with improved startability, which is constructed by combining a high-pressure sodium lamp with a built-in starter device and a ballast.

[Technical background and problems]

As is well known, the high-pressure sodium lamp device with a built-in starting device has a circuit configuration in which a high-pressure sodium lamp with a built-in starting device configured as shown in Fig. 1 is combined with a ballast as shown in Fig. 2. It has been established. That is, a high-pressure sodium lamp with a built-in starter device has an alumina ceramic discharge tube 3 sealed with a rare gas for starting, such as xenon gas and sodium, supported by a support wire 4 in an outer bulb 2 having a cap 1 at one end. In addition, the starting device 5 is installed internally. Here, the starter device 5 is composed of, for example, a bimetal switch 5a that is closed at room temperature and a filament 5b that is located near the bimetal switch 5a and heats the bimetal switch 5a. Furthermore, the first
In the figure, 6 is the getter, 7 is the starting auxiliary conductor, and 8 is the getter.
numeral 9 represents a top spring, numeral 9 represents an arc tube holder, and numerals 10 and 11 electrically connect to the base 1 through internal lead wires.

The high-pressure sodium lamp 12 with a built-in starter device constructed as described above is combined with the ballast 14 disposed on the side of the power source 13 to form a high-pressure sodium lamp device.

By the way, in this high-pressure sodium lamp device with a built-in starter device, the switch 13a of the power source 13
When turned on, a voltage is applied to the starter device 5 and the discharge tube 3 via the ballast 14. At this time, in the starting device 5, a current flows between the heating filament 5b and the bimetal switch 5a, and the bimetal switch 5 is activated by the heat generated by the heating filament 5b.
a is opened, and by opening the bimetal switch 5a, a pulse voltage with a high peak value is generated, and this pulse voltage is superimposed on the voltage on the power supply side and is applied between both electrodes of the discharge tube 3, and the starting assist In combination with the action of the conductor 7, the required discharge and lighting are started. However, although the pulses generated in such a lamp device have a peak value of several thousand volts, the pulse width is extremely narrow, on the order of several microseconds, and the pulse peak value and width vary depending on where in the AC phase the switch operates. also changes. For this reason, there are problems in that lamp starting becomes uncertain and the life of the ballast 14 tends to be shortened due to high voltage pulses being applied to the ballast 14 many times. That is, when the discharge tube 3 is started by the starting device 5, when a pulse is applied between the two main electrodes, the auxiliary electrode is first activated in the path from one main pole to the inner wall surface of the discharge tube 3 near the starting auxiliary conductor 7 to the other main pole. A discharge path is formed, and then a stable discharge occurs between the two main electrodes. Therefore, to start a lamp (discharge tube), a pulse voltage is required for initial dielectric breakdown, and a peak value is required to quickly form an electron emitting part in the main electrode and easily transition to and stabilize the discharge between the main electrodes. In addition, it is desirable that the pulse width be as wide as possible and that lighting be started with as few pulses as possible.

[Purpose of the invention]

The present invention addresses the above-mentioned disadvantages and provides a highly practical high-pressure sodium lamp device with a built-in starter device that improves the reliability of starting and lighting the lamp and extends the life of the ballast. That is.

[Key points of the invention]

The present invention provides a high-pressure sodium lamp device with a built-in starter device, in which the startability of the lamp device is affected by the stray capacitance of the conductive wire portion that electrically connects the discharge tube and the ballast. When selected and set in a predetermined relationship with the enclosed rare gas pressure, starting (lighting) is ensured by applying superimposed pulses.
This was done with the aim of preventing damage to the ballast, which is a part of the lamp device.

That is, in an experiment to improve the starting performance of this type of high-pressure sodium lamp device, the present invention found that the reliability of starting was determined by the noble gas pressure PX (Torr) charged in the discharge tube.
It is greatly influenced by the stray capacitance PF (picofu-rad) of the conductive wire connecting the ballast and the discharge tube, and if the relationship of logPF0.805logPX−0.046 logPF−0.384logPX+4.976 is satisfied, starting lighting is reliable.
This is based on the knowledge that as a result, the life of the ballast is extended (because the number of pulse applications with high peak values is reduced).

[Embodiments of the invention]

Approximately 350 torr of xenon was filled as a starting gas.
The first test using a high pressure sodium discharge tube rated at 360W.
A high-pressure sodium lamp device with a built-in starter device having the circuit configuration shown in the second diagram was obtained by combining the high-pressure sodium lamp 12 with a built-in starter device as shown in the figure and the high-efficiency ballast 14 for a general 400W mercury lamp. In the above circuit configuration, the conductive wire 15 connecting the high pressure sodium lamp 12 and the ballast 14
a and 15b are made by bundling two vinyl sheathed cables with a copper wire with a diameter of about 1 mm as the core wire and vinyl chloride resin as the insulator and sheath.If you change the length, in other words, you can change the stray capacitance. Ta.

High-pressure sodium lamp device with the above configuration (20 each
lamp), the rated voltage of the ballast 14 is
When 200V (power supply voltage) was applied and the startability was examined, it was found that the relationship between the stray capacitance of the conductive wires 15a and 15b and the startability was as shown in the third diagram. Third
In the figure, the vertical axis shows the percentage (%) of starting lighting (stable discharge) within the predetermined time, the horizontal axis shows the stray capacitance PF, and the curve A shows the predetermined time within 10 seconds (starting device activation 1 to 2). Curve B is a case where the predetermined time is within 30 seconds (about 8 to 11 operations of the starter).

In the above, the stray capacitance of the conductive wires 15a, 15b was adjusted by changing the lengths of the conductive wires 15a, 15b, but it is also possible to bundle (twist), change the number of vinyl sheathed cables, or arrange them (for example, in parallel). It can also be adjusted by changing the material, thickness, etc. of the covering insulator. For example, in the high-pressure sodium lamp device having the above configuration, when the conductive wires 15a and 15b are made of vinyl-coated electric wires, and 3 to 200 wires are twisted together to change the stray capacitance (Fig. 4),
Similar results were obtained when captire cables of different lengths were used as the conductive wires 15a and 15b (FIG. 5).

However, the stray capacitance of these conductive wires 15a and 15b is determined by the direct reading universal bridge (Model 4274A manufactured by YHP, Multi Flexenry LCR).
Conductive wires 15a, 15b to be measured using a meter)
The measurement was carried out by opening one end of the device and connecting the other end to the terminal of the measuring device. This measurement value is obtained by alternately replacing the conductive wires 15a, 15b and capacitors to be measured and connecting them to the ballast 14, observing the generated pulse waveform, and measuring the frequency of the resonant vibration waveform of the pulse. It was also equivalent if

As is clear from FIGS. 3 to 5 above, the stray capacitance PF of the conductive wires 15a and 15b that electrically connect the ballast 14 and the sodium lamp 12 is
1 to 1 by setting it to 100 to 10000 picorads
The lamp is easily started and lit by applying two pulses. Incidentally, this startability is also influenced by the pressure of the starting gas enclosed in the discharge tube 3. For example, when the pressure of the filled gas is low, the distance that charged particles such as electrons and ions can move increases, making it easier for initial dielectric breakdown to occur and for discharge to continue after dielectric breakdown. Therefore, even if the peak value of the pulse superimposed on the power supply voltage for starting lighting is low, and even if the pulse width is narrow, good starting performance can be achieved.

From this point of view, a sodium lamp device is constructed in which the amount of starting gas charged (filling pressure) is varied in the discharge tube 3 of the high-pressure sodium lamp device with a built-in starting device, and the filling gas pressure PX ( ) and conductive wires 15a, 15b
Stray capacitance PF (Picoflat) and startability (10
As a result of further examination of the relationship between starting and lighting within seconds, both showed good starting performance within the range shown by straight lines C and D in Figure 6, and as a result, damage to the ballast 14 was completely prevented. It has been confirmed that this can be prevented.

The conditions for achieving good starting characteristics as shown in Fig. 6 above can be expressed using the formula logPF0.805logPX-0.046 logPF-0.384logPX+4.976 (where PF is the floating capacity (picolad) and PX is the filled gas pressure (torr). )) As long as this condition is satisfied, good startability and long life of the ballast will be achieved.

In the above example, xenon is used as the filled gas, but it is also possible to use a discharge tube 3 filled with krypton or argon, or the combined ballast is not for a mercury lamp, but a dedicated slow-phase ballast. A similar effect was observed in the case of Also, 180W as a high pressure sodium lamp with built-in starter device.
Even when the lamp device was combined with a rated lamp or a 940W rated lamp and a ballast for a 200W mercury lamp or a ballast for a 1kW mercury lamp, good startability was achieved as long as the conditions shown by the above formula were satisfied.

〔Effect of the invention〕

As mentioned above, in a high-pressure sodium lamp device that combines a high-pressure sodium lamp with a built-in starting device and a ballast, the stray capacitance PF of the conductive wire portion that electrically connects the ballast and the lamp, and the main part of the lamp. The gist of the present invention is to select and set the sealed gas pressure PX of the discharge tube to a predetermined condition (relationship). However, according to the present invention, the built-in starting device is activated only once or twice to easily start and light the lamp. On the other hand, the fact that the number of activations of the starter is sufficient means that the chances of applying a pulse voltage with a high peak value to the ballast are reduced, which reduces the risk of damage to the ballast, and the ballast itself has a long lifespan. It can withstand use for a long period of time (long life). Thus, it can be said that the high-pressure sodium lamp device according to the present invention provides great practical advantages in terms of excellent startability and a longer life of the ballast. Although it is conceivable to use a capacitor as a means for adjusting the stray capacitance, there is a problem that the capacitor is easily punctured, in other words, the electric circuit is easily short-circuited or opened, and the intended effect cannot be sufficiently achieved.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of the configuration of a high-pressure sodium lamp with a built-in starting device, FIG. 2 is a block diagram showing an example of the configuration of a high-pressure sodium lamp with a built-in starting device, and FIGS. 3 to 5 are according to the present invention. A curve diagram showing the relationship between the stray capacitance of the conductive wire portion connecting the ballast and the lamp in the high-pressure sodium lamp device and the startability, respectively, and FIG. 6 is a curve diagram connecting the ballast and the lamp in the high-pressure sodium lamp device according to the present invention. FIG. 3 is a diagram showing the relationship between the stray capacitance of a conductive wire portion, the pressure of the gas filled in the lamp, and the startability. 12... High-pressure sodium lamp with built-in starting device, 14... Ballast, 15a, 15b... Conductive wire.

Claims (1)

[Scope of Claims] 1. A high-pressure sodium lamp device comprising a high-pressure sodium lamp in which a discharge tube and a starter device are housed in an outer bulb, and a ballast disposed on the power source side of the high-pressure sodium lamp. , the stray capacitance PF (picofuard) of the conductive wire that electrically connects the high-pressure sodium lamp and the ballast.
and the starting noble gas pressure PX (Torr) sealed in the discharge tube satisfy the following relational expression: logPF0.805logPX−0.046 logPF−0.384logPX+4.976. lamp device.