JPH0973880A - Conductive fly-proof cover and electrodeless fluorescent lamp - Google Patents

Abstract

(57) [Summary] [Structure] A conductive fly-proof cover composed of a cover 1 having a good light transmittance, a light-transmitting shield sheet having a high conductivity, and an adhesive for bonding both. Further, a light source is composed of a discharge vessel 9 covered with a conductive fly-proof cover having high light transmittance, an excitation coil 7 and a lighting circuit 6 provided therein, and a phosphor 8 is generated by ultraviolet rays excited and radiated by high frequency discharge. To emit light. [Effect] The use of the conductive fly-proof cover can significantly reduce the electromagnetic radiation noise of the lamp to the outside. Further, it is possible to realize an electrodeless fluorescent lamp with a conductive fly-proof cover that has a long life, high efficiency, and is strong against external impacts and does not emit electromagnetic waves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flyproof cover for a lamp and an electrodeless fluorescent lamp.

[0002]

2. Description of the Related Art As a light source for illumination, a fluorescent lamp for generating a discharge having a commercial frequency or a frequency of about several tens of kHz is widely used. These fluorescent lamps are usually tubular or curved and have electrodes at both ends. A voltage is applied between the electrodes to obtain a commercial frequency or several tens of kilohertz.
A discharge having a frequency of about z is generated, and ultraviolet light generated by the discharge is converted into visible light by a phosphor applied on the inner surface of the glass container and is extracted to the outside. The electrodes are coated with an electron emitting material that easily emits electrons into the discharge space. This electron emitting material reduces sputtering by ions and scattering by evaporation due to temperature rise. When the electron-emitting material is exhausted, electrons are hardly emitted from the electrodes, and the discharge cannot be maintained. Therefore, the life of a lamp having such an electrode is determined by the consumption of the electron emitting material applied to the electrode.

Further, as a fly-proof cover for preventing the scattering of glass, phosphors and the like when these fluorescent lamps are damaged, many fly-proof covers made of polyester tubes or the like have been used. There was no.

Recently, a long-life electrodeless fluorescent lamp has been studied. For example, there is JP-A-63-310550. Electrodeless fluorescent lamps generate high-frequency induction by applying a high-frequency current to an induction coil placed close to the discharge vessel containing the discharge gas or by applying a high-frequency voltage to a pair of counter electrodes placed close to the discharge vessel. It discharges and discharges the discharge gas in the discharge vessel with an electromagnetic field. The frequency of the high frequency is about several MHz to several tens MHz. Since this electrodeless fluorescent lamp has no electrode inside the discharge vessel, it has a long life regardless of the consumption of the electron emitting material. However, since the electrodeless fluorescent lamp is lit at a high frequency, electromagnetic radiation noise is easily generated, and some kind of shielding means is required. In the conventional shield means of an electrodeless fluorescent lamp, a transparent conductive film such as a nesa film is integrally formed on the bulb surface, or the bulb is covered with a wire mesh for shielding.

[0005]

The conventional fly-proof cover has a problem that, for example, electromagnetic radiation noise of an inverter-lit lamp at several tens of kHz is emitted to the outside.

Further, in the conventional electrodeless fluorescent lamp, no measures have been taken against scattering when the lamp is damaged. In addition, a complicated manufacturing process is required to integrally form the transparent conductive film on the valve surface.

[0007]

In order to solve the above problems, in the present invention, the flying cover is coated with a conductive material for preventing electromagnetic waves from being emitted to the outside.

Further, an electrodeless fluorescent lamp is constituted by a coil for generating a high frequency induction electromagnetic field by passing a high frequency current near the discharge vessel having no electrode inside and a high frequency power source required for lighting. A structure that covers the electrodeless fluorescent lamp with a conductive fly-proof cover.

[0009]

According to the structure of the present invention, since the conductive fly-proof cover is provided, it is possible to realize the function of preventing the damage due to the impact from the outside and the emission of the electromagnetic wave, and the high frequency power supply and the coil generate the high frequency induction electromagnetic field. In addition, it is possible to discharge and emit light by the discharge container. Moreover, since no electrodes are used, a long-life and highly efficient light source can be realized.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of a conductive fly-proof cover according to the present invention. The cover 1 covering the outer circumference is made of vinyl chloride. The exterior is U-shaped and requires a lamp bulb storage space inside. A light-transmitting shield sheet 3 having high conductivity is provided on the inner surface of the cover 1 that covers the outer periphery. The light-transmitting shield sheet 3 is made of acrylic and is tin-plated to form a mesh. The adhesive 2 for joining the cover 1 covering the outer periphery and the light-transmitting shield sheet 3 is made of silicon. Further, a belt 4 is provided to attach a cover to the lamp. The belt 4 is contractible and is, for example, a component such as a rubber band.

FIG. 2 shows an embodiment of the electrodeless fluorescent lamp of the present invention. The phosphor 8 is coated on the inner surface of the discharge container 9. A lighting circuit 6 is installed below the discharge vessel 9 and has a power supply port 5 for connecting to a commercial power source. Lighting circuit 6
Generates a high frequency of several MHz from a commercial power source. The high frequency output of the lighting circuit 6 is connected to the excitation coil 7.

The operation at the time of lighting is as follows. It is connected to a commercial power source, and high-frequency power is supplied from the lighting circuit 6 to the excitation coil 7. A high frequency electromagnetic field generated around the coil generates a ring-shaped high frequency plasma concentric with the coil around the coil. Ultraviolet rays generated from the high-frequency plasma are applied to the phosphor 8 to be converted into visible light, which is taken out of the discharge container 9. Further, the conductive fly-proof cover of FIG. 1 is attached as shown in FIG. 2, and covers the entire discharge vessel 9 and is fixed by the belt 4. By adjusting the belt 4, the conductive fly-proof cover of FIG. 1 can be removed. The conductive fly-proof cover of FIG. 1 may be directly fixed to the discharge vessel 9 with an adhesive having high transparency.

In the embodiment, mercury and argon gas are used as the substances to be enclosed in the discharge vessel 1. However, the present invention is not limited to these. For example, various amalgams can be used instead of mercury. In this case, amalgam having the highest luminous efficiency is selected according to the temperature of the lamp during the operation of the lamp. This makes it possible to cope with various operating conditions of the lamp. Further, xenon gas or neon gas can be used instead of the argon gas. Alternatively, no mercury may be used and only a rare gas such as xenon may be used. In this case, it is possible to realize a lamp that has stable temperature characteristics regardless of the ambient temperature and has a quick start-up at the time of starting.

FIG. 3 shows an embodiment of an inverter lighting fluorescent lamp having a conductive fly-proof cover of the present invention. The phosphor 11 is applied to the inner surface of the straight tube type discharge container 10, and has power supply ports at both ends, and the inverter is turned on by a high frequency of 55 kHz. Further, a conductive fly-proof cover is provided on the outer periphery of the straight tube type discharge vessel 10, and the vinyl chloride 1, the light transmitting shield sheet 3, the adhesive 2, and the straight tube type discharge are provided as in FIGS. A belt 4 is attached to the container 10 from both ends.

[0015]

According to the present invention, the conventional fly-proof cover can solve the problem that the electromagnetic radiation noise of the lamp during high frequency lighting is emitted to the outside. The use of the conductive fly-proof cover can significantly reduce the emission of electromagnetic radiation noise from the lamp. Further, since the electrodeless fluorescent lamp having a long life and high efficiency is provided with the conductive fly-proof cover, it is possible to prevent scattering and electromagnetic noise emission due to external impact.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a conductive fly-proof cover according to the present invention.

FIG. 2 is a sectional view showing an electrodeless fluorescent lamp according to the present invention.

FIG. 3 is a cross-sectional view showing an inverter lighting fluorescent lamp provided with a conductive fly-proof cover.

[Explanation of symbols]

1 ... Cover, 2 ... Adhesive, 3 ... Light-transmissive shield sheet, 4 ... Belt, 5 ... Power supply port, 6 ... Lighting circuit, 7 ...
Excitation coil, 8 ... Phosphor, 9 ... Discharge container.

Claims (3)

[Claims] 1. A fly-proof cover for a lamp, which is electrically conductive, and which has conductivity. 2. An electrodeless fluorescent lamp having the conductive flyproof cover according to claim 1. 3. The electrodeless fluorescent lamp according to claim 2, wherein the conductive fly-proof cover is removable.