JP3489679B2 - Fluorescent lamp device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a fluorescent lamp device having a bent discharge path. 2. Description of the Related Art A plurality of straight pipe bulbs are arranged in parallel, and the internal spaces of the bulbs are connected at each end to form one bent discharge path as a whole, and at both ends of the discharge path. 2. Description of the Related Art There is known a fluorescent lamp device in which a light emitting tube on which a filament electrode is formed is supported on a support case having a socket attached to a socket at one end, and a circuit device for lighting the light emitting tube at high frequency is built in the support case. The tube diameter of this fluorescent lamp device is 1
Two types of 7.5 mm and 12.5 mm are known, and the wattage is 27 W when the tube outer diameter is 17.5 mm.
Hereinafter, when the pipe outer diameter is 12.5 mm, the power is 17 W or less. It has been found that when the diameter of the arc tube of such a fluorescent lamp device is made smaller and the wattage is made higher, the temperature of the outer wall surface of the arc tube near the electrodes becomes considerably higher. Was. In particular, at the end of the life of the arc tube, the high-frequency lighting circuit may run away, and since the high-frequency lighting is performed, the discharge continues even if the filament is broken. In this case, the surface temperature of the outer wall of the arc tube near the electrode becomes lower. About 2 degrees Celsius
It turned out to rise considerably from 00 degrees. For example, when the outer diameter of the tube is 12.5 mm and the lamp power is 23 W, the surface temperature of the outer surface of the arc tube near the electrode rises to nearly 400 degrees Celsius, and the arc tube support of the arc tube support case melts. Problem occurred. Further, even if a temperature fuse or the like is provided and the operation can be stopped in the event of such a runaway of the lighting circuit, it may take time to stop the operation. In some cases, the melting of the cases was not completely eliminated. [0005] Further, as described above, as the tube diameter is small and the lamp input is large, the inner wall of the arc tube near the electrode is strongly blackened by end glow generated by preheating of the filament electrode at the time of starting, and the appearance is extremely high. There was also the problem of damage. The present invention has been made in view of the above problems, and an object of the present invention is to provide a fluorescent lamp device in which an arc tube support portion of an arc tube support case is difficult to melt. In the fluorescent lamp device according to the first aspect of the present invention, a plurality of straight tube bulbs having a tube inner diameter of 12 mm or less are arranged in parallel, and the internal space of the bulb is connected at each end. As a whole, one bent discharge path is formed, filament electrodes are formed at both ends of the discharge path, and the distance from the bulb end to the electrode is at least 20 mm. A thermoplastic material in which the two arranged ends are inserted and supported at one end and supported so that the distance from the boundary of the supporting portion to the electrode is at least 10 mm, and the other end is provided with a base fitted to a socket. And a circuit device for lighting the arc tube at a high frequency of 18 W or higher. According to the fluorescent lamp device of the first aspect of the present invention, by using an arc tube having a small tube diameter in a lamp having a high lamp power, the surface temperature of the outer wall of the arc tube near the electrode rises to nearly 400 degrees Celsius. Even if the electrode and thermoplastic material
Since the distance to the supporting case is increased, the supporting case can be prevented from melting even when the circuit runs away. FIG. 1 is a front view of a fluorescent lamp device according to an embodiment of the present invention, FIG. 2 is a longitudinal sectional view, and FIG. 3 is a plan view. The fluorescent lamp device includes an arc tube 1, a supporting case 3 supporting the arc tube 1, and a lighting circuit component 2, and a base 4 provided at one end of the supporting case 3. In the arc tube 1, four straight tube bulbs 1a are arranged in parallel, and their ends are connected by connecting portions 1b and 1c, so that the internal space of the bulb as a whole forms one bent discharge path. It is connected as follows. Filament electrodes 5 are provided at both ends of the discharge path. The two ends 1d having the filament electrode 5 and the two ends 1e having no electrode are juxtaposed. In addition, there is one connection portion 1b near the end portion where the filament electrode 5 is formed, while there are two connection portions 1c on the other end side where the filament electrode 5 is not formed. The connection part 1c is 1
It is obtained by bending a straight pipe-shaped valve into a U-shape. In the arc tube 1, several milligrams of mercury and several torr of argon gas are sealed. Four straight pipe valves 1a
Have a tube outer diameter of 12.5 mm and an inner diameter of 10.
5 mm. The length of each straight pipe valve 1a is 12
1 mm, the discharge path length was 445 mm, and the distance from the tube end 1d to the filament electrode 5 was 22 mm. The filament electrode 5 is implanted in a flare stem (not shown), and the distance from the top of the flare stem to the filament electrode 5 is 6 mm. The arc tube 1 has one end inserted into a fitting hole 6 formed in the support case 3 and fixed with a heat-resistant silicone adhesive 7. The fitting hole is a first fitting hole 6a into which two ends 1d having a filament electrode are inserted and fixed.
And a second fitting hole 6b into which the two ends 1e having no filament electrode are inserted and fixed. Each of the first fitting hole 6a and the second fitting hole 6b is shaped like a gourd as shown in FIG. 4 because the ends of two adjacent straight pipe valves are inserted into the first fitting hole 6a and the second fitting hole 6b. That is, FIG.
1 shows a flat portion 3a formed on the side of the arc tube 1 and a first fitting hole 6a and a second fitting hole 6b formed in the flat portion 3a. Both the first fitting hole 6a and the second fitting hole 6b are formed with circular holes so that the ends of the two straight pipe valves can be inserted and fixed. It is connected to one and has a gourd shape. The diameter of the circular portion of the first fitting hole 6a is about 15 mm, and the diameter of the circular portion of the second fitting hole 6b is about 13 mm. Outer diameter of straight pipe valve 12.5m
The gap of the first fitting hole 6a is considerably larger than m. Due to this gap, the influence of heat generated by the filament electrode 5 can be considerably reduced. The distance from the flat portion 3a of the supporting case 3 on which the arc tube 1 is supported to the filament electrode 5 is 13.5 mm, which is 5 mm longer than the conventional one. This makes it difficult for the influence of the heat generated by the filament electrode 5 to be transmitted to the flat portion 3a of the support case 3. The lighting circuit component 2 in the support case 3 is mounted on the circuit board 7 of the support case 3, and the tallest circuit component, in this embodiment, a cylindrical aluminum electrolytic capacitor is placed in the base 4. Part of the space is inserted into the formed space. In this embodiment, the support case 3 is composed of a support cover 3a for supporting the arc tube and a base case 3b to which the base 4 is attached, and the circuit board 7 is fixed to the support cover 3a. As shown in FIG. 5, the lighting circuit includes a known series inverter 9 including a resonance circuit in which an inductance L2 and a capacitor C10 are connected in series as a high-frequency power supply circuit, and a capacitor C10 connected in parallel to the arc tube 1 as a starting circuit. Further, both ends of each filament electrode 5 are connected to the power supply circuit side at the same potential because of the simple starting method. Because of such a circuit, the preheating current does not flow through the filament electrode 5 even at the time of starting, and the arc tube 1 is turned on. The input power to the arc tube 1 is 21 W, and the power consumption including the circuit loss is 23 W. One of the reasons why such a simple starting method has become possible is to devise a constant of the filament electrode 5.
That is, the filament electrode 5 is a triple coil, and its constants are as follows. Here, not only the value of the constant of the present embodiment but also a preferable range and the coil constant in the case of the conventional preheating method are described. [Table 1] The starting operation of the above fluorescent lamp device is as follows. That is, when the power is turned on, the series inverter 9 performs a resonance operation, and the arc tube 1 starts discharging due to the high voltage generated on both sides of the capacitor C10. At this time, since the filament electrode 5 is not preheated, the end glow seen in the preheating start method hardly occurs. For this reason, scattering of the electron-emitting substance due to discharge between both ends of the filament due to end glow can be prevented, and as a result,
Blackening of the arc tube 1 near the electrodes can be suppressed. Such blackening occurs remarkably when the inner diameter of the tube is 12 mm or less and the input power to the arc tube 1 is 18 W or more. However, when the inner diameter of the tube exceeds 12 mm, the electron emitting material scattered by end glow. When the input power to the arc tube 1 is less than 18 W and the end glow is not so strong, the non-preheating simple start method as in the above embodiment has a tube inner diameter of 12 mm or less. When the input power to the arc tube 1 is 18 W or more, it is extremely effective. In particular, one of the reasons why such a non-preheating simple starting method has become possible is to devise a constant of the filament electrode 5. In other words, even if a high voltage is applied without preheating, a triple coil that does not easily scatter the electron-emitting substance is used, and no preheating current is passed. It is possible to make the wire diameter thicker than before, so that it is difficult to break the wire. In addition, since the number of turns of the tertiary coil is reduced, there is an effect that arc transition easily occurs without preheating. Further, since the wire diameter of the main wire is increased, the stiffness of the filament electrode 5 is increased, so that the electron emitting material is less likely to fall off due to vibration or the like. The above-described effects can be obtained within the preferable ranges described in Table 1 above. Here, the sub-wire diameter, the primary coil pitch, the secondary coil pitch, and the tertiary coil pitch can be designed relatively freely. The clamp width is determined by the inner diameter of the bulb of the arc tube 1. In the above fluorescent lamp device, during lighting, the surface temperature of the bulb outer wall near the electrode reaches as high as 400 degrees Celsius, but the distance between the filament electrode 5 and the flat portion 3a of the support case 3 is at least 10 mm. Therefore, the temperature drop was remarkable, and the temperature was more than 200 degrees because the distance was only 8.5 mm in the past.
By setting it to 5 mm, it became possible to make it less than 200 degrees. This temperature is a temperature corresponding to the surface temperature of the bulb outer wall near the electrode in the case of the conventional tube outer diameter of 15.5 mm. Further, in the above fluorescent lamp device, the first fitting hole 6a for supporting the end 1d of the straight tube bulb 1a having the filament electrode 5 is larger than the second fitting hole 6b. The distance between the supporting part of the valve and the outer wall of the valve is set and the distance between the supporting part and the valve is fixed with a heat-resistant silicone adhesive. May affect the
That is, specifically, the possibility that the support case 3 is melted becomes extremely small. The first fitting hole 6a is
As in the case of b, when the size is very small, the heat of the outer wall of the valve may not be sufficiently dissipated, and the outer wall of the valve may directly contact the support case 3. Is extremely small. In the above embodiment, the temperature fuse TF is provided, which is necessary because of the non-preheating start method, but is not necessary in the case of the preheating start method. This is because, in the case of the preheating start method, if the filament electrode 5 is disconnected, the discharge can be stopped without the flow of the preheating current. From the temperature fuse TF, etc.
Circuit must be stopped. The connecting portion is not limited to one obtained by forming a U-shape, but may be an H-shaped connecting portion which connects two straight pipe type valves. The arc tube is not limited to one in which four straight tube bulbs are connected, and may have another shape such as one in which six straight tube bulbs are connected. Further, the first fitting hole 6a and the second fitting hole 6b are both gourd-shaped, but when the interval between the straight pipe valves 1a is wide, fitting holes are respectively formed in the straight pipe valves 1a. It may be provided independently. According to the fluorescent lamp device of the first aspect of the present invention, in a lamp having a high lamp power, an arc tube having a small tube diameter is used, so that the outer wall surface temperature of the arc tube near the electrode is 400 degrees Celsius. Since the distance between the electrode and the supporting case made of a thermoplastic material is increased even when the circuit goes up close, the supporting case can be prevented from melting even when the circuit runs away.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a fluorescent lamp device according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the fluorescent lamp device according to the embodiment of the present invention. FIG. 3 is a plan view of the fluorescent lamp device according to the embodiment of the present invention. FIG. 4 is a layout view of a first fitting hole and a second fitting hole of the fluorescent lamp device according to the embodiment of the present invention. FIG. 5 is a lighting circuit diagram of the fluorescent lamp device according to the embodiment of the present invention. [Description of Signs] 1 ... Emission tube, 1a ... Straight tube bulb, 1b, 1c ... Connection, 1d, 1e ... End, 2 ... Lighting circuit parts, 3 ...
・ Support case, 4 ・ ・ ・ Base, 5 ・ ・ ・ Filament electrode, 9
... Series inverters.

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI H05B 41/24 F21Y 103: 025 // F21Y 103: 025 F21S 5/00 B (58) Fields surveyed (Int.Cl. ⁷ , (DB name) H01J 61/30 F21S 2/00 F21V 23/00 390 H01J 61/067 H05B 41/00 H05B 41/24 F21Y 103: 025

Claims (1)

(57) [Claims 1] A plurality of straight pipe valves having a pipe inner diameter of 12 mm or less are arranged in parallel, and the internal space of the bulb is connected at each end to form a single bent discharge as a whole. An arc tube in which a filament path is formed at both ends of the discharge path and the distance from the bulb end to the electrode exceeds at least 20 mm; and two ends where the electrodes of the arc tube are arranged are inserted. A supporting case made of a thermoplastic material, which is supported at one end and supported so that the distance from the boundary of the supporting portion to the electrode is at least 10 mm or more, and the other end of which is provided with a base fitted to a socket; And a circuit device for lighting at a high frequency of 18 W or more.