JP2588651Y2 - UV inspection lamp - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a black light (ultraviolet flaw detection lamp) used for fluorescent magnetic particle flaw detection and fluorescence penetrant flaw detection.

[0002]

2. Description of the Related Art In a conventional ultraviolet inspection lamp, light from an ultraviolet light source directly reaches an ultraviolet transmission filter. Therefore, since the ultraviolet transmission filter brings heat, it is subjected to a heat-resistant strengthening treatment to prevent the filter from being damaged.

In a small ultraviolet inspection lamp that irradiates a relatively narrow range (for example, a range of 600.times.200 mm) with a high ultraviolet intensity, light from a light source is concentrated within a predetermined range so that light emitted outside the range is minimized. There is a need to. For this purpose, for example, the reflecting mirror of the ultraviolet inspection lamp, the band-shaped plate forming a parabolic curved surface at a position slightly past the vertex of the parabolic curved surface,
Of the strips cut in a direction transverse to the strip, two strips including the apex are prepared as reflectors, and these reflectors are opposed to each other on a reflective surface and are joined to each other at the cutting edge. The present inventors have devised and filed an application in which a tube is arranged below the joining line between the two reflectors (Japanese Utility Model Application No. 4-57418).

[0004]

[Problem to be solved by the present invention]
In the case of the ultraviolet flaw detection lamp as in the invention of No. 8, a portion where the heat rays of the infrared portion converge appears near the ultraviolet transmission filter. In particular, in the case of a small ultraviolet inspection lamp, it is difficult to keep the distance between the light source and the filter, so that it is inevitable that the condensing portion appears near the center of the ultraviolet transmission filter. When heat rays are collected near the center of the UV transmission filter, a temperature difference occurs between the center and the periphery of the UV transmission filter, causing the UV transmission filter to expand unevenly. Resulting in. The inventor found that the coefficient of thermal expansion was 9.3 × 10 ^-6
When an experiment was conducted using an ultraviolet transmission filter with a size of K- ¹ and a size of 90 x 225 x 5 mm, it was found that the temperature difference between the center and the end of the 225 mm in the lengthwise direction was about 120 ° C or more, which caused damage. It turned out to be.

According to the present invention, the above disadvantages are improved,
It is an object of the present invention to provide a small-sized ultraviolet inspection lamp having high ultraviolet intensity, which prevents damage to an ultraviolet transmission filter.

[0006]

A solution for the] The present invention is, in the ultraviolet flaw lamp housing the ultraviolet light source and ultraviolet transmission filter in the lamp, the thermal expansion coefficient 3 × 10 ^-6 K between the ultraviolet light source and ultraviolet transmission filter ^- An ultraviolet flaw detection lamp in which ¹ or less transparent heat-resistant glass plates are installed.

Here, a transparent heat-resistant glass plate having a coefficient of thermal expansion of 3 × 10 ⁻⁶ K ⁻¹ or less is known. In the ultraviolet detector lamp of the present invention, various known transparent heat-resistant glass plates can be used, but the coefficient of thermal expansion is preferably 0.5 × 10 ^{−6 to} 3 × 10 ^6.
A glass plate of ^-6 K ^-1 such as a low alkali glass of borosilicate or quartz glass is used. Preferred examples of the glass include Pyrex (trademark) manufactured by Corning Corporation in the United States and Tempax (trademark) manufactured by Iwaki Glass Co., Ltd. Glass made with a coefficient of thermal expansion exceeding 3 × 10 ^-6 K ^-1 will break itself. The thickness of the glass plate is selected so that the attenuation of the transmission of the ultraviolet intensity is not excessive. When the Pyrex or Tempax plate has a specific thickness, the UV intensity attenuation is as follows: thickness 2 mm, attenuation 5%, thickness 4 mm, attenuation 10%,
6mm thickness, 15% attenuation.

Generally, the thickness of the glass plate is preferably 1 to 8 mm, particularly preferably 2 to 6 mm.

The above-mentioned transparent heat-resistant glass plate is provided between the light source and the ultraviolet transmission filter. Preferably, 1 to 1 on the upper part of the ultraviolet transmission filter (that is, from the light source).
It is installed at intervals of 20 mm, especially 1 to 10 mm. The transparent heat-resistant glass plate is preferably installed so as to be parallel to the ultraviolet transmission filter. Two or more transparent heat-resistant glass plates can be installed.

In the present invention, heat rays from the light source are reflected on the surface of the transparent heat-resistant glass plate, or are converted into heat in the transparent heat-resistant glass plate and emitted as radiation. As a result, heat rays reaching the ultraviolet transmission filter are reduced, and a sharp rise in temperature at the center of the filter is suppressed. As a result, the temperature difference between the center and the periphery of the ultraviolet transmission filter is low, for example, about 120 The temperature is kept below ℃ to prevent breakage of the filter.

[0011] In the ultraviolet flaw detection lamp of the present invention, a condensing reflector is preferably provided behind the ultraviolet light source,
Therefore, a condensing portion is generated. The shape and position of the reflector are not particularly limited. However, in order to concentrate light (ultraviolet rays) within a narrow range and irradiate the test object with uniform ultraviolet intensity, the above-mentioned Japanese Patent Application No. 4-57418 is used. It is preferred to be as described in In other words, at a position slightly past the vertex of the parabolic curved surface, the belt-shaped plate forming the parabolic curved surface, two of the band-shaped plates cut in the direction crossing the band-shaped plate, the two band-shaped plates including the apex are prepared as reflectors, It is preferable that these reflectors are opposed to each other on a reflection surface and are joined to each other at the cutting edge to form a reflector, and a light source (ultraviolet tube) is disposed below a joining line of the two reflectors. . In this preferred embodiment, the joining of the two parabolic curved reflectors at the joining line may be performed by welding the reflectors to each other to form an integral unit, or may be removably connected by bolts via a flange. good. Further, both side openings of the parabolic curved reflecting plate can be closed by the side reflecting plate. This allows the reflected light to be concentrated in a rectangular irradiation area. It should be noted that a deviation occurs between the reflecting mirror and the central axis of the tube due to variations in the shape of the ultraviolet tube. Further, the desired light distribution area changes depending on the size of the inspection surface. Therefore, in order to be able to adjust the relative position between the reflector and the tube, the tube is adjusted vertically and horizontally by screws or other well-known means just below the joining line of the two reflectors with a parabolic curved surface. Preferably, it is provided as possible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the following embodiments.

FIGS. 1 and 2 are a side view and a front view, respectively, of the ultraviolet inspection lamp used in the first to third embodiments. The ultraviolet ray inspection lamp is essentially composed of an ultraviolet ray tube 10, a reflecting mirror 20 arranged so as to surround the ultraviolet ray tube 10, and an ultraviolet transmitting filter 30 attached to an opening of the reflecting mirror 20. , And a transparent heat-resistant glass plate 31 provided between the ultraviolet tube 10 and the ultraviolet transmission filter 31. In the ultraviolet inspection lamp used in the fourth embodiment, two transparent heat-resistant glass plates are provided.

Here, the reflecting mirror 20 is arranged such that the strip-shaped plates forming the parabolic curved surface are positioned at positions slightly past the vertices 22 and 22 'of the parabolic curved surface (the position of the line L in FIG. 1). Of the strips cut in the transverse direction, two strips including the vertices 22 and 22 'are prepared as reflectors 26 and 26', and these reflectors are prepared.
26, 26 'are made to face each other at the reflection surface and are joined to each other at the cut edge. Therefore, the reflection plates 26 and 2
The curved shape of the reflecting surface composed of 6 ′ has a shape in which the innermost portion has a convex portion in the direction of the bulb 10 on the joining line L of the reflector, and as is apparent from FIG. The emitted light is reflected toward the test object without hitting the tube 10 when reflected by the reflecting surface in the range between the vertices 22 and 22 'of the reflecting plates 26 and 26', and is reflected twice. Never. The joining at the joining line L of the two parabolic curved reflecting plates 26, 26 'is shown in FIG.
As described above, are removably connected by bolts via flanges 28 and 28 '. In addition, a parabolic curved reflector
The openings on both side surfaces of 26 and 26 'are closed by side reflection plates 29 and 29' as is clear from FIG. Thereby, the reflected light can be concentrated in the rectangular irradiation range.

FIG. 3 shows that light from the tube 10 is reflected by the reflectors 26 and 2.
This shows a state where the light is reflected by the 6 ′ reflecting mirror 20 and irradiated on the irradiation surface.

[0016]

Embodiment 1 An ultraviolet inspection lamp shown in FIGS. 1 and 2 was used. The distance between the top of the reflector and the transparent heat-resistant glass is 150m
m, the distance from the center of the bulb is 30 mm, and the focal point is 30 mm below the transparent heat-resistant glass. A Pyrex glass plate having a size of 3 (thickness) x 130 (tube direction) x 225 (depth) mm was used as the glass plate 31, and was placed at a position 2 mm above a heat-strengthened ultraviolet light transmitting filter of the same size. . Turn on the UV lamp 10 for 60 minutes, and then measure the temperature at the center of the UV transmission filter and 30 minutes from the end in the 225 mm direction.
The temperature at the position of mm was measured. FIG. 4 shows the results. 60
After one minute, the temperature at the center of the ultraviolet transmission filter was 178 ° C., the temperature at a position 30 mm from the end in the 225 mm direction was 84 ° C., and the difference was 94 ° C. The UV transmission filter did not break.

[0017]

Example 2 The same operation as in Example 1 was performed except that the Pyrex glass plate was placed at a position 5 mm above the ultraviolet transmission filter. FIG. 5 shows the measurement results of the temperature at the center of the ultraviolet transmission filter during lighting and the temperature at a position 30 mm from the end in the 225 mm direction. The temperature at the center of the UV transmission filter after 60 minutes is 154 ° C, 30mm from the end in the 225mm direction
Temperature was 61 ° C, and the difference was 93 ° C. The UV transmission filter did not break.

[0018]

Embodiment 3 As the glass plate 31, 2 (thickness) × 130 × 22
The same operation as in Example 1 was performed, except that a 5 mm size Tempax glass plate was used and the filter was set at a position 5 mm above the ultraviolet transmission filter. FIG. 6 shows the measurement results of the temperature at the center of the ultraviolet transmission filter during lighting and the temperature at a position 30 mm from the end in the 225 mm direction. After 60 minutes, the temperature at the center of the ultraviolet transmission filter was 171 ° C., the temperature at a position 30 mm from the end in the 225 mm direction was 60 ° C., and the difference was 111 ° C. The UV transmission filter did not break.

[0019]

Example 4 The same operation as in Example 1 was carried out except that two Tempax glass plates each having a size of 2 (thickness) × 130 × 225 mm were placed at positions of 5 mm and 8 mm above the ultraviolet transmission filter, respectively. went. FIG. 7 shows the measurement results of the temperature at the center of the ultraviolet transmission filter during lighting and the temperature at a position 30 mm from the end in the 225 mm direction. After 60 minutes, the temperature at the center of the ultraviolet transmission filter was 165 ° C., the temperature at a position 30 mm from the end in the 225 mm direction was 64 ° C., and the difference was 101 ° C. The UV transmission filter did not break.

[0020]

Comparative Example The same operation as in Example 1 was performed except that a transparent heat-resistant glass plate was not used. FIG. 8 shows the measurement results of the temperature at the center of the ultraviolet transmission filter during lighting and the temperature at a position 30 mm from the end in the 225 mm direction. It is clear that the temperature difference between the central part and the peripheral part of the filter is large and the temperature rise rate of the entire filter is large as compared with the case of the ultraviolet inspection lamp having the glass plate. The UV transmission filter broke after 15 minutes. The temperature at the center of the ultraviolet transmission filter at the time of breakage was 194 ° C, the temperature at a position 30 mm from the end in the 225 mm direction was 74 ° C, and the difference was 120 ° C.

[0021]

According to the present invention, it is possible to prevent the ultraviolet transmission filter from being damaged. The effect of the present invention is remarkable in the conventional ultraviolet flaw detection lamp, especially in the case of a small ultraviolet flaw detection lamp capable of irradiating a uniform high ultraviolet intensity within a certain range, in view of the fact that the ultraviolet transmission filter is easily broken.

[Brief description of the drawings]

FIG. 1 is a side view of an ultraviolet inspection lamp according to the present invention.

FIG. 2 is a front view of the ultraviolet inspection lamp of FIG. 1;

FIG. 3 is a diagram showing a reflection state of light by a parabolic curved reflecting plate in the ultraviolet inspection lamp of FIGS. 1 and 2;

FIG. 4 is a graph in which the measurement results of the temperature of each part of the ultraviolet transmission filter during the operation of the ultraviolet lamp in Example 1 are plotted.

FIG. 5 is a graph in which the measurement results of the temperature of each part of the ultraviolet transmission filter during the operation of the ultraviolet lamp in Example 2 are plotted.

FIG. 6 is a graph plotting the measurement results of the temperature of each part of the ultraviolet transmission filter during ultraviolet lamp lighting in Example 3.

FIG. 7 is a graph in which the measurement results of the temperature of each part of the ultraviolet transmission filter during the operation of the ultraviolet lamp in Example 4 are plotted.

FIG. 8 is a graph plotting the measurement results of the temperature of each part of the ultraviolet transmission filter during the operation of the ultraviolet lamp in the comparative example.

DESCRIPTION OF SYMBOLS 10 UV bulb 20 Reflector mirror 22, 22 ′ Apex of parabolic curved surface 26, 26 ′ Reflector L Joint line A Central axis of UV bulb 29, 29 ′ Side reflector 30 Ultraviolet transmission filter 31 Transparent Heat-resistant glass plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01N 21/91 G01N 27/84

Claims (2)

(57) [Scope of request for utility model registration] 1. An ultraviolet flaw detection lamp in which an ultraviolet light source and an ultraviolet transmission filter are housed in a lamp, a transparent heat-resistant glass plate having a thermal expansion coefficient of 3 × 10 ⁻⁶ K ⁻¹ or less is provided between the ultraviolet light source and the ultraviolet transmission filter. An ultraviolet flaw detection lamp characterized by the following. 2. A condensing reflector is provided behind the ultraviolet light source, and the reflector has a band-like plate that forms a parabolic curved surface at a position slightly past the vertex of the parabolic curved surface. Two of the strips including the vertices are prepared as reflectors among the strips cut in a direction crossing the direction, and these reflectors are formed by facing each other at the reflection surface and joining each other at the cutting edge, thereby forming a tube. 2. The ultraviolet inspection lamp according to claim 1, wherein a sphere is arranged below a joining line between the two reflectors.