JPS61165948A - Microwave discharge light source - Google Patents

Abstract

PURPOSE:To prevent any leakage of microwave by making 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 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. The mesh plate 7 has a step-like curved surface 7b from which a contact area 7a extends toward a flanged area 10 so that the plate 7 has a spring effect. Therefore, even when the contact surfaces of flanged areas 8 and 10 are somewhat rough, it is possible to achieve completely close contact by deforming the contact area 7a. Consequently, any leakage of microwave can be prevented.

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 the figure, (1) is a magnetron that generates microwaves, (21 is a magnetron antenna of this magnetron, and (3) is this antenna (2). A waveguide that transmits microwaves emitted from (4) is this waveguide (3)
The cavity wall (41 is a spherical part (5) and the circumference of the cylindrical part (4a) connected to the spherical part (5) extends outward. 0 (7), which is composed of a cylindrical part (6) having a bent flange part αq and made of aluminum or the like, is connected to the opening part (4) of the cavity wall (4).
4a), and this metal mesh plate (7) is placed over the metal mesh plate (7) to tighten the presser flange (8), which serves as a presser metal fitting, with the presser screw (9). [Tighten. The metal mesh plate (7) blocks microwaves but allows light to pass through, and together with the cavity wall (4), constitutes a microwave cavity αυ. α3 is a spherical blank located near the center of the spherical portion (5) of the cavity wall (4)! A Usui discharge lamp is made of quartz glass, etc., and is filled with a rare gas such as argon, a metal such as mercury or iron, and a halogen such as iodine. α-shape is a protrusion provided on a part of the outer wall of the discharge lamp [3], and is like a quartz glass whose one end is inserted and supported in the spherical part (51) of the discharge lamp support part αη formed at the top of the cavity wall (4). A cylindrical support member made of a low-loss dielectric material (I9 is fitted into a flared support part t1e formed at the other end, and supports the discharge lamp 0. tle is a metal mesh This is a lens for condensing light emitted from the plate (7) to the outside onto an irradiated surface (not shown).

Next, the operation will be explained. When the power is turned on, the magnetron +11 generates microwaves, which 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 the feed port α force, forming a microwave electromagnetic field within the cavity c111. The rare gas in the discharge lamp σJ is discharged by this microwave electromagnetic field, and the inner wall of the discharge lamp αJ is heated.

For this reason, mercury, iron, etc. in the discharge lamp aJ become halides and evaporate, and the discharge is mainly a discharge of metal gas, and light having 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 u3. That is, the light emitted from the discharge lamp U has a spherical shape. Therefore, if the spherical part +51 of the cavity wall (4) is made a light reflecting surface, the nine reflected lights will pass near the discharge lamp a3 again since the discharge lamp αJ is located near the center of the spherical part 151. This reflected light and the direct light from the discharge lamp αJ are radiated outward through the metal mesh plate (7). The light emitted outward is then focused by a condensing lens (II) onto a necessary irradiated surface.

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

Contact surface (7a) of metal mesh plate (7) and flange portion Q
The contact surface (10a) of 1 is pressed into electrical contact with the cap screw (9). 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 outside the microwave cavity 0υ. When using a large microwave, 7 lunges Q
The contact surface (10a) of l and the contact surface of presser flange (8) (
8a) needs to be machined into a highly accurate flat surface to produce a contact effect. Further, a large number of holding screws (9) are required all around the circumference.

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and the contact part of the metal mesh plate with the 7 flange part is processed to have a curved surface having spring properties so as to protrude toward the 7 flange part side. By doing so, it is an object of the present invention to provide a microwave discharge light source device that does not require flat finishing of the flange portion and does not leak microwaves even with a small number of holding screws.

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 3, the contact part (7a) of the metal menyu plate (7)
) is machined with a curved surface having spring properties so as to protrude toward the flange portion 01j, and this curved surface is a stepped curved surface (7b) in this example. In other words, since the one-step curved surface has a spring action, even if the contact surface (10a) of the flange portion a1 and the contact surface (8a) of the presser foot 7 flange (8) are rough, the presser screw (9) When the presser foot 7 langes (8) are tightened to the flange portion Ql, for example, presser foot 2 langes (8)
) and the contact surface (10a) of the flange part α [
) is a convex part, the step-like curved surface (7b) of the metal mesh plate (7) is crushed and deformed, while the concave part is not crushed, and therefore the contact surface of the metal mesh plate (7) (7a) is in electrical contact with the contact surface (10a) of the 7 flange portion a1 completely over the entire circumference. As a result, there is no gap between the two contact surfaces (7a) and (10a), so there is no possibility that the microwave cavity (ID) will cause a discharge between the contact surfaces due to the microwaves and the microwaves will not leak to the outside. In addition, the number of holding screws (9) can be reduced over the entire circumference.For example, if the diameter of the microwave cavity αυ is 1
In the case of 30 am, only 3 push screws are required @Figure 4 shows an example of a metal mesh plate (force contact part (7a)) @In this example, the contact surface of the metal mesh plate (7) A convex surface (7c) having a springiness of 1 is formed over the entire circumference.In this case as well, the contact surface (7a) of the metal mesh plate and the contact surface (10a) of the flange portion aCt are similar to the stepped curved surface (7b).
) is in contact with the entire circumference.

FIG. 5 shows other fastening means in place of the cap screw (9). For this tightening, for example, catch clips ω manufactured by Takigen Manufacturing Co., Ltd. are used at several locations around the entire circumference. This clip ω has a hook 0υ attached to the outside of one flange portion α1, and a hook G1 attached to the other presser foot 7 flange (8).
A hook is provided to which the first band is hung. In this way, even if clip ω is used, the presser foot 7 flange (8) can be tightened to the flange portion α1, and the contact surface (7a) of the metal mesh plate can be brought into good contact with the contact surface (10a) of the flange portion α1, so the presser foot 3 can be tightened. The metal mesh plate can be easily attached and detached in place of the screws (9). Furthermore, the fifth
In the figure, the curved surface of the metal mesh plate (7) has a stepped direction ik (7
Although the example using b) is shown, a convex surface (7C) may be used.

As described above, according to the present invention, there is provided a cavity wall having an opening on at least one side and a flange provided around the opening, and a metal mesh having nine overlapping 7 flange portions so as to close the opening. A microwave discharge light source device comprising a microwave cavity in which a plate is attached with a holding metal fitting, and an electrodeless discharge lamp inside the cavity.

By processing the contact surface of the metal mesh plate with the flange part to have a springy curved surface so as to protrude toward the flange part, the contact between the metal mesh plate and the flange part of the microwave cavity wall is perfect, and as a result, Precision is not required on both contact surfaces of the metal mesh plate and flange, and simple tightening is effective in preventing discharge and microwave leakage.

[Brief explanation of the drawing]

Figure 1 is a sectional view 9 of the configuration of a conventional microwave discharge light source device.
FIG. 2 is a sectional view showing the installation of the metal mesh plate. 9. FIG. 3 is a sectional view similar to FIG. 2 according to the present invention. FIG. 4 is a sectional view of another embodiment. It is a figure of another Example of. (4)...Cavity wall, (7)...Metal mesh plate,
(7a)...Contact surface, (7b)...Stepped curved surface,
(7c)... Convex surface, (8)... Presser flange,
(9)...Pressure screw, α1...7 U/J part, α TO...
・Microwave cavity, αJ...electrodeless discharge lamp, ω...
clip. In addition, in Figure 1, the same reference numerals indicate the same or equivalent parts.

Claims (3)

[Claims] (1) A cavity wall having an opening on at least one side and a flange around the opening, and a metal mesh plate overlaid on the flange so as to close the opening are attached using a tightening means. A microwave discharge light source device comprising a microwave cavity and an electrodeless discharge lamp in the cavity, characterized in that a surface of the metal mesh plate corresponding to the flange portion is curved. Discharge light source device. (2) The microwave discharge light source device according to claim 1, wherein the contact portion of the metal mesh plate is a stepped curved surface. (3) The microwave discharge light source device according to claim 1, wherein the contact portion of the metal mesh plate has a convex curved surface.