JPS61165949A - Microwave discharge light source - Google Patents

Abstract

PURPOSE:To prevent any leakage of microwave by making the area of a metallic mesh plate facing the flanged area of the microwave cavity have a curved surface having a spring effect when the metallic mesh plate is placed in such a manner as to close the opening of the cavity wall. CONSTITUTION:Microwave from a magnetron 1 is passed through a waveguide 3 and then is introduced into a microwave cavity 11 consisting of a semispherical part 5 and a metallic mesh plate 7 for closing the opening. An electrodeless discharge lamp 13 installed in the cavity 11 is discharged to produce light which is then introduced outside the cavity 11 through the mesh plate 7. In this device, either an elastic body 20 made of silicone rubber or similar material or a metallic plate having a spring effect is interposed near the contact area between the mesh plate 7 and flanged areas 8 and 10. Therefore, even when the contact surfaces of the flanged areas 8 and 10 are somewhat rough, it is possible to achieve completely close contact by deforming the elastic body 20. Consequently, it is possible prevent any discharge or leakage of microwave.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microwave discharge light source device that utilizes light emission by microwave discharge.

Figure 1 shows a conventionally proposed microwave discharge light source device.In Figure 9, (1) is the magnetron that generates microwaves, (2) is the magnetron antenna of this magnetron, and (3I is this antenna (2)). A waveguide that transmits microwaves emitted from (4) is this waveguide (3)
The cavity wall (4) is connected to the end of the microwave power supply port Q3 via the microwave power supply port Q3, and the cavity wall (4) is connected to the spherical surface part +51 and a flange part that is bent outward around the opening (4a). It consists of a cylindrical part (6) having αC, and is made of aluminum etc. (7) is the opening of the cavity wall (4) (
4a), and this metal mesh plate (7) is overlaid on the holding flange (8), which serves as a holding fitting, and is tightened with a holding screw (9''), which is the means for tightening the flange part decoy. The metal mesh plate (7) blocks microwaves but allows light to pass through. Together with the cavity wall (4), it constitutes the microwave cavity αυ. 0 is the cavity A spherical electrodeless discharge lamp placed near the center of the spherical part (5) of the wall (4).It is made of quartz glass, etc., and contains rare gases such as argon, metals such as mercury or iron, and iodine, etc. of halogen is enclosed.α
◆ is a protrusion provided on a part of the outer wall of the discharge lamp αJ, which corresponds to the discharge lamp support part α formed on the top of the spherical part (5) of the cavity wall (4).
One end of the cylindrical support US made of a low-loss dielectric material such as quartz glass is inserted into and supported by the flared support part αe formed at the other end of the cylindrical support US. I support it. Ql is a metal mesh plate (a lens for condensing light emitted to the outside by force onto a surface to be irradiated (not shown)).

Next, the operation will be explained. When you turn on the power.

Microwaves are generated by the magnetron tl+ and are radiated into the waveguide (3) through the antenna (2). This microwave propagates through the waveguide (3) and is radiated into the microwave cavity αυ through nine feed ports aa, forming a microwave electromagnetic field within the cavity αυ. Due to this microwave electromagnetic field, the rare gas in the discharge lamp a3 is discharged, and the inner wall of the discharge lamp a3 is heated. Therefore, mercury, iron, etc. in the discharge lamp αJ become halides and evaporate.
The discharge is mainly a discharge of metal gas, and light with a specific emission spectrum depending on the type of enclosed metal is emitted. The discharge at this time occurs near the tube wall of the discharge lamp α3. That is, the light emitted from the discharge lamp σJ has a spherical shape. Therefore, if the spherical part (5) of the cavity wall (4) is used as a light-reflecting surface, it is possible to
The reflected light passes near the discharge lamp 03 again.

This reflected light and the direct light of the discharge lamp u3 are connected to the metal mesh plate (7
) is radiated outward through. Then, the light emitted outward is focused on a necessary irradiated surface by a condensing lens α seconds.

Figure 2 shows an enlarged view of the installation of the metal mesh plate (7).

Contact surface (7a) of metal mesh plate (7) and 7 langes 0
The contact surface (10a) of No. 1 is pressed and electrically contacted by the cap screw (9). Therefore, if the contact is not made completely over the entire circumference, discharge due to microwaves will occur in the part where the contact is incomplete, and microwaves may leak to the outside of the microwave cavity aυ. When using a large microwave, 7 lunges α
1 contact surface (10a) 9 presser flange (8) contact surface (
8a) needs to be machined into a highly accurate flat surface to produce a contact effect. Also, a large number of holding screws (9) are required all around the circumference.

This invention was made to eliminate the drawbacks of the conventional ones as described above, and by interposing an elastic body between the metal mesh plate and the flange of the presser foot 7, the contact surface (10a) of the flange portion The object of the present invention is to provide a microwave discharge light source device that does not require a flat surface finish and does not leak microwaves even with a small number of retaining screws (9) ◇ An embodiment of the present invention will be described below with reference to the drawings. .

In FIG. 3, an elastic body (2) is interposed between the metal mesh plate (7) and a holding flange (8) serving as a holding fitting. It is preferable that this elastic body ① is a packing material made of silicone rubber. By interposing the elastic body ① in this way, the contact surface (I Da) of the flange portion QQ and the flange 7 (8) of the presser foot 7 are Even if the contact surface (8a) is a rough surface, by tightening the presser flange (8) with the presser screw (9), for example, the contact surface (8a) of the presser flange (8). The elastic body ■ is crushed in the convex portion of the contact surface (10a) of the second flange portion tte, while the concave portion is not crushed, so that the contact surface (7a) of the metal mesh plate (7) is fully compressed. completely around 7
It can be brought into electrical contact with the contact surface (10a) of the flange portion a1. This allows both contact surfaces (7a) and (10a
) Since there is no gap between the contact surfaces, the microwaves generated between the contact surfaces by the microwaves in the microwave cavity συ will not leak to the outside. Further, the number of retaining screws (9) can be reduced over the entire circumference. For example, if the diameter of the microwave cavity aυ is 130 mm, only three cap screws are required.

FIG. 4 shows another embodiment of the elastic body. This elastic body is made of a spring plate Qυ. In this case as well, the contact surface (7) of the metal mesh plate (7) is similar to the silicone rubber gasket.
a) and the flange portion (IG contact surface (10a)) can be completely contacted over the entire circumference.

FIG. 5 shows other fastening means in place of the cap screw (9). For this tightening, for example, catch clips (2) manufactured by Takigen Manufacturing Co., Ltd. are used at several locations around the entire circumference. This clip GO.

A latching fitting 01) is attached to the outside of one flange portion αQ, and a hook portion (to) to which the band c (2) of the latching fitting GO is latched is provided on the other presser flange (8). Even when used, the presser flange (8) is attached to the flange part C.
By tightening the LI, the contact surface (7a) of the metal mesh plate can be brought into good contact with the contact surface (10a) of the 7 flange part a, so the metal mesh plate can be attached and removed in place of the 9 retainer screw (9). It can be done easily. Although FIG. 5 shows an example in which the elastic body (2) is a silicone rubber gasket, a spring plate may also be used.

As described above, according to the present invention, the cavity wall has an opening on at least one side and a flange is provided around the opening, and a metal mesh plate is stacked on the flange so as to close the opening. In a microwave discharge light source device, the microwave discharge light source device includes a microwave cavity mounted with a holding metal fitting, and an electrodeless lamp within the cavity.

By interposing the elastic body between the metal mesh plate and the holding metal fitting, the metal mesh plate and the flange part of the microwave cavity wall are in complete contact, and as a result, the contact surface of the metal mesh plate and the flange part Precision of the contact surface is not required.9 In addition, simple tightening is effective in preventing discharge and microwave leakage.0

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the configuration of a conventional microwave discharge light source device.
FIG. 2 is a cross-sectional view showing the installation of the metal mesh plate, FIG. 3 is a cross-sectional view similar to FIG. 2 according to the present invention, FIG. 4 is a cross-sectional view of another embodiment, and FIG. 5 is a tightening means. FIG. 3 is a sectional view of another embodiment of the invention. (4)...Cavity wall, (7)...Metal mesh plate, (
8)... Presser foot 7 lunge, (9j... Presser screw, αa
...7 lange part, αυ...microwave cavity, Qt.
・Electrodeless discharge lamp, ■...Elastic body. Qυ...spring plate, ■...clip. In Figure 9, the same symbols indicate the same or corresponding parts.

Claims (3)

[Claims] (1) A metal mesh plate placed over the flange so as to close the upper opening is placed on a cavity wall having an opening on at least one side and a flange around the opening, and a metal fitting and a fastening means. A microwave cavity mounted using
A microwave discharge light source device comprising an electrodeless discharge lamp in the cavity, characterized in that an elastic body is interposed between the metal mesh plate and the fastening means. (2) The microwave discharge light source device according to claim 1, wherein the elastic body is made of silicone rubber. (3) The microwave discharge light source device according to claim 1, wherein the elastic body is made of a spring plate.