JP2011045807A - Ultraviolet irradiation apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the degree of uniformity of luminous intensity distribution by making aperture ratios of RF screens of lamp houses which are arranged on both ends where electrodeless lamps are lit and that of the RF screen of another lamp house to be arranged inside different from each other. <P>SOLUTION: A microwave is generated from a magnetron 13. A plurality of ultraviolet irradiation parts 10A-10D are irradiated with the microwave. Each of ultraviolet irradiation parts comprises the lamp house 25 where the electrodeless lamp 26 for emitting ultraviolet light is enclosed in a bulb. The discharge medium is excited by the microwave so that the electrodeless lamp 26 emits ultraviolet light, the emitted ultraviolet light are reflected by light reflectors 281, 282 and a body to be irradiated is irradiated with the reflected ultraviolet light through an irradiation window 30 of the lamp house 25. A mesh of the RF screen 31 to be arranged on the irradiation window 30 of each of ultraviolet irradiation parts 10A, 10D is made coarser than that of the RF screen 29 to be arranged on the irradiation window 30 of each of ultraviolet irradiation parts 10B, 10C so that infrared light are cut and the microwave does not leak. As a result, the degree of uniformity of luminous intensity distribution can be improved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultraviolet irradiation device using an electrodeless lamp that emits ultraviolet rays by being excited by microwaves.

  A conventional ultraviolet irradiation device that emits ultraviolet rays from an electrodeless lamp using microwaves is used for printing-related ink drying, semiconductor-related fine exposure, liquid crystal-related adhesive curing, and the like. The irradiation area is lengthened by connecting a plurality of ultraviolet irradiation devices equipped with such microwave-feeding electrodeless lamps so that the central axes of the electrodeless lamps are on the same line. . (For example, Patent Document 1)

JP 2008-53014 A

  In the technique of Patent Document 1 described above, a plurality of lamp houses that excite the discharge medium of an electrodeless lamp by microwaves to emit ultraviolet rays are arranged so that the central axis of the electrodeless lamp is on the same line. It aims to make it easier.

  However, in the light distribution when a plurality of electrodeless lamps are arranged so that the central axes thereof are on the same line and the irradiation area is elongated, the electrodeless lamps located on the inner side with respect to the illuminance of the electrodeless lamps located at both ends There is a problem that the degree of uniformity cannot be obtained in the lamp length direction because the value is low with respect to the illuminance of.

  The object of the present invention is to change the aperture ratio of the RF screen between the lamp house arranged at both ends where the electrodeless lamp is lit and the lamp house arranged at the center, and to achieve a high uniformity in the light distribution obtained from each lamp house An object of the present invention is to provide an ultraviolet irradiation device having a high degree of accuracy.

  In order to solve the above-described problems, an ultraviolet irradiation device of the present invention includes an electrodeless lamp that encloses a discharge medium and emits ultraviolet light by exciting the discharge medium with microwaves, and the electrodeless lamp. A lamp house capable of irradiating ultraviolet rays to the outside, and an RF cut filter installed under the ultraviolet irradiation surface to limit the ultraviolet rays emitted from the lamp house and prevent leakage of the microwaves, When a plurality of ultraviolet irradiation units are arranged so that the central axis of the electrodeless lamp is on the same line, the mesh of the RF filter is formed in order to make the light distribution uniform. It is characterized by changes depending on the installation location.

  According to the present invention, by changing the aperture ratio of the RF screen of the lamp house arranged at both ends and the lamp house arranged at the center, high uniformity is obtained in the light distribution obtained from each lamp house. It becomes possible.

It is a system configuration diagram for explaining one embodiment about the ultraviolet irradiation device of this invention. It is a block diagram of the principal part of FIG. It is a block diagram of the principal part of FIG. It is a block diagram of the principal part of FIG. It is a top view of the principal part of FIG. It is a bottom view of the principal part of FIG. It is a block diagram for demonstrating an example of the electrodeless lamp used by embodiment of FIG. It is explanatory drawing for demonstrating the effect of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

1 to 9 are diagrams for explaining a first embodiment of the ultraviolet irradiation apparatus according to the present invention. FIG. 1 is a schematic configuration diagram, FIG. 2 is a configuration diagram of a main part of FIG. 1, and FIG. 4 is a block diagram of the main part of FIG. 1, FIG. 5 is a top view of the main part of FIG. 2, and FIG. 6 is a bottom view of the main part of FIG.
In FIG. 1, 11 is a lighting device comprising a high-voltage power supply 12 and a magnetron 13 that is driven by the high-voltage power supply 12 to generate microwaves. The lighting device 11 is accommodated in a housing 14 formed of a material that can be electromagnetically shielded. The output of the magnetron 13 is sent to the connector 15.

  FIG. 2 shows a specific configuration example between the magnetron 13 and the connector 15. Microwaves emitted from the antenna ANT of the magnetron 13 based on the high-voltage power supply 12 are supplied to the connector 15 via the waveguide 16 and the coaxial / waveguide converter 17.

  FIG. 3 shows a specific configuration example of the coaxial / waveguide converter 17. The coaxial / waveguide converter 17 is electromagnetically coupled to a microwave generated from the antenna ANT from a waveguide 16 formed in a cylindrical shape with a material that can be electromagnetically shielded as an output of the lighting device 11. To the connector 15. Further, the microwaves are transmitted from the connector 15 to one end of the coaxial cable 18. The connector 15 is mechanically and electromagnetically coupled by an operation of screwing into a screw cut at a joint with the waveguide 16.

  In FIG. 1, FIG. 2, and FIG. 4, the microwave transmitted via the coaxial cable 18 is supplied to the distributor 20 via the connector 19. The distributor 20 has a conductive box shape, for example, made of aluminum. The distributor 20 transmits microwaves to the connectors 21a to 21d, respectively.

  Further, the microwaves are transmitted from the connectors 21a to 21d to one ends of the corresponding coaxial cables 22a to 22d, respectively. Microwaves are supplied from the other ends of the coaxial cables 22a to 22d to the ultraviolet irradiation units 10A to 10D via the connector 23 and the matching units 24a to 24d, respectively.

  Here, 10A to 10D are ultraviolet irradiation units that irradiate ultraviolet rays emitted from electrodeless lamps by microwave power feeding. The ultraviolet irradiation units 10A to 10D have the same configuration. Hereinafter, the basic ultraviolet irradiation unit will be described with respect to the ultraviolet irradiation device 10A, and the description of the ultraviolet irradiation units 10B to 10D will be replaced with different components. Will also be described for the ultraviolet irradiation units 10B to 10D.

  In FIG. 1 and FIG. 2, the ultraviolet irradiation unit 10B 25 is a lamp house having an electromagnetic shielding function, and both ends in the longitudinal direction of the electrodeless lamp 26 are attached and arranged in the lower central part in the lamp house 25. is there. Further, a cooling fan 27 for cooling the electrodeless lamp 26 and the like by blowing air, for example, is installed inside the lamp house 25 at the upper part of the lamp house 25.

  Reflecting plates 281 and 282 are installed on the back side of the electrodeless lamp 26. In addition, an RF screen 29 is provided in an irradiation window 30 opened below the lamp house 25 between the reflecting surface side of the reflecting plates 281 and 282 and an irradiated object (not shown). The RF screen 29 is fixed to the bottom of the lamp house 25 with a fixing means such as a screw so as to cover the entire surface of the irradiation window 30.

  The RF screen 29 is formed by knitting a metal wire into an IR cut filter that cuts infrared rays or by punching a metal plate into a microplate, so that the microtron with an oscillation frequency of 2.45 GHz, for example, of the magnetron 13 is formed. It is composed of an RF screen having a mesh size large enough to prevent leakage of waves and allow sufficient passage of ultraviolet light.

  As shown in FIG. 6, among the four ultraviolet irradiation units 10A to 10D, the ultraviolet irradiation units 10B and 10C use the same mesh size. The ultraviolet irradiation units 10A and 10D located at both ends use an RF screen 31 having a mesh larger than that of the RF screen 29 within a range where infrared rays can be cut and microwaves do not leak.

  That is, the ultraviolet irradiation units 10A and 10D positioned at both ends receive a stronger microwave than the ultraviolet irradiation units 10B and 10C positioned between them. In other words, the illuminance of the ultraviolet irradiation units 10A and 10D is slightly brighter than that of the ultraviolet irradiation units 10B and 10C.

  As the RF screen 29, it is conceivable to use a common one for the ultraviolet irradiation units 10B and 10C. However, considering replacement of the electrodeless lamp 26, it is a best practice to use separate ones.

  Here, a configuration example of the electrodeless lamp 26 will be described with reference to FIG. Reference numeral 261 denotes a cylindrical bulb having a length of about 240 mm made of quartz glass that transmits ultraviolet light. The outer diameter of the valve 261 is about 17 mm, for example. A light-emitting space 262 of the bulb 261 is filled with an inert gas and a discharge medium that discharges with a microwave mainly composed of mercury and iron. Support portions 263 and 264 that support the valve 261 are formed integrally with the valve 261 at both ends of the valve 261.

  FIG. 8 shows a comparison of the light distribution when a plurality of ultraviolet irradiation sections are arranged so that the central axes of the present invention and the conventional electrodeless lamp are on the same line, and the irradiation area is lengthened. . At this time, the microwaves to be radiated to the electrodeless lamps of the respective ultraviolet irradiation sections are required to have the same value.

  In the conventional case, the electrodeless lamp without the electrodeless lamp of the ultraviolet irradiation part next to the ultraviolet irradiation part located at both ends not only makes a difference in illuminance from the electrodeless lamp of the other party, UV absorption by the house occurs.

  For this reason, as shown by the broken line in FIG. 8, the illuminance at both ends of the light distribution is lowered. In the case of using an apparatus that takes this decrease into account, the good irradiation area becomes narrow by that amount, resulting in poor efficiency.

  In the case of this invention, among the plurality of ultraviolet irradiation units, the RF screens 31 of the ultraviolet irradiation units 10A and 10D located at both ends of the plurality of ultraviolet irradiation units so that the center axes of the electrodeless lamps are on the same line are connected to the ultraviolet irradiation units 10B and 10C. An RF screen 31 having a coarser mesh than the RF screen 29 is used.

  The illuminance that has passed through the coarse RF screen 31 generated by each of the ultraviolet irradiation units 10A and 10D is slightly higher than the illuminance that has passed through the fine RF screen 29 that is individually generated by the ultraviolet irradiation units 10B and 10C. It will be. For this reason, as shown by a solid line in FIG. 8, it is possible to suppress a decrease in illuminance at both ends of the light distribution. Since it is not necessary to take into account the decrease at both ends, a good irradiation area is widened accordingly, and it is possible to cope with ultraviolet irradiation of a larger irradiated object.

  The present invention is not limited to the above-described embodiment. For example, the lighting device has a plurality of lamp houses in common, but may be provided individually for each lamp house. In addition, in the case where an individual lighting device is provided for each ultraviolet irradiation unit, the same applies to the case where the lighting device is controlled to control the illuminance of the electrodeless lamp to form the light distribution shown by the solid line in FIG. There is an effect.

  Furthermore, in the above-described embodiment, four ultraviolet irradiation units are given as an example. However, if the central axes of the electrodeless lamps of three or more ultraviolet irradiation units are arranged on the same line, the present invention The idea can be applied.

10A to 10D Ultraviolet irradiation unit 11 Lighting device 12 High voltage power supply 13 Magnetron 14 Case ANT Antenna 25 Lamp house 26 Electrode lamp 27 Cooling fans 281 and 282 Reflective plates 29 and 31 RF screen 30 Irradiation window

Claims (3)

An electrodeless lamp that encloses a discharge medium and emits ultraviolet light by exciting the discharge medium with microwaves;
A lamp house that houses the electrodeless lamp and that can be irradiated with ultraviolet rays to the outside;
In order to limit the ultraviolet rays emitted from the lamp house and prevent leakage of the microwaves, an ultraviolet ray irradiating unit is configured from an RF cut filter installed below the ultraviolet ray irradiating surface,
When a plurality of ultraviolet irradiation units are arranged so that the central axis of the electrodeless lamp is on the same line, the mesh of the RF filter is changed depending on the installation location in order to make the light distribution uniform. A featured ultraviolet irradiation device.   2. The ultraviolet irradiation apparatus according to claim 1, wherein the ultraviolet irradiation unit is configured such that central axes of the electrodeless lamps of at least three ultraviolet irradiation units are arranged on the same line.   3. The ultraviolet irradiation according to claim 1, wherein the plurality of ultraviolet irradiation units arranged so that the central axes of the electrodeless lamps are on the same line have roughened meshes of the RF filters located at both ends. apparatus.

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