JPH0633408Y2 - Dust visual inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a device for detecting fine dust floating in the air or in a liquid, and more specifically to a visual field of a device for visually detecting fine dust. It is about improvement.

(B) Conventional Technology Conventionally, as a dust detection device, a dust measuring instrument that uses scattered light and a dust meter that measures the weight of dust to calculate the dust concentration have been used.

Further, the present inventors have proposed a visual device for irradiating floating fine dust with a light beam and observing it in the dark field of a magnifying glass (Japanese Patent Application Nos. 58-171535 and 60-60). 1856
No. 74, Japanese Patent Application No. Sho 62-088386).

(C) Problems to be solved by the device In the above-mentioned conventional apparatus, the scattered light type or weight type dust meter is unsuitable as a simple portable dust detection apparatus because it is heavy and complicated to handle and expensive. Met.

In addition, in the conventional dust visual inspection system, the inner wall of the sample chamber was made black and the light was diffused and reflected from the illuminated surface when the light-irradiated portion was not sufficiently dark. May decrease the visibility of dust.

It is an object of the present invention to provide a portable dust detection device which eliminates the drawbacks of the conventional device and has a clear visual confirmation of dust.

(D) Means for Solving the Problems The present invention will be described with reference to the drawings. In FIG. 1, the inside of a rectangular tubular casing 1 is partitioned by a partition plate 12 having a slit 4, and a lamp 2, on the right side, The condenser lens 3 is provided, and the lamp 2
The observation chamber 13 is formed by providing a magnifying glass 7 on the upper surface on the left side which collects the light, and the entire inner surface of the observation chamber 13 is formed of a specular black member.

(E) Action In the first dust visual inspection apparatus having such a structure, the light of the lamp 2 is condensed by the condenser lens 3, and the partition plate 12
The stray light is cut by and becomes a light beam 5 which passes through the slit 4 and enters the sample chamber 13.

The light beam 5 that has entered the sample chamber 13 is specularly reflected by the facing wall surface because the inner wall of the sample chamber 13 is a specular black member.
Further, specular reflection is repeated on the opposing wall surface, and after the reflection of several orders, it is almost absorbed by the wall surface.

Therefore, if the position and direction of the magnifying glass 7 are selected, the reflected light does not enter the field of view of the magnifying glass 7, so that the diffused light is scattered in all directions due to diffused reflection as in the sample chamber of a conventional device with a vanishing finish. The night vision of the field of view of the mirror is not disturbed.

Thus, in the present invention, the suspended dust illuminated by the light beam 5 is observed as a clear bright spot in the excellent dark field of the magnifying glass 7.

(F) Embodiment FIG. 1 is a sectional view of a dust visual inspection apparatus according to an embodiment of the present invention.

In the figure, a partition plate is provided for the housing 1 having wall surfaces parallel to each other.
Circular slit 4 provided on the partition plate 12 by dividing by 12
Is located on the same axis as the condenser lens 3 and the lamp 2 provided on the right side of the partition plate 12.

Sample chamber formed on the left side of the housing 1 partitioned by the partition plate 12
A magnifying glass 7 is provided on the top surface of 13 so that its optical axis is orthogonal to the top surface, and the light beam 5 is collected by a lamp 2 which is condensed by a condenser lens 3 and stray light is cut by a plurality of slits 4. The point 14 is located in the field of view of the magnifying glass 7.

The inner surface of the sample chamber 13 is made of a mirror-finished black acrylic resin, and the sample inlets 8 provided on both sides of the sample chamber 13 are provided with open / close lids 15 that slide left and right. Is provided with a light-absorbing member 6 that obliquely intersects the light beam 5 at an intersection angle θ of 90 ° or less.

Now, in this embodiment, when the lamp 2 is turned on by a switch (not shown), the light condensed by the condenser lens 3 passes through the slit 4 and becomes a light beam 5 which enters the sample chamber 13 and is opposed to the light. The surface of the absorbing member 6 is irradiated.

Most of the light beam 5 projected on the surface of the light absorbing member 6 is absorbed by the member 6, and a part of the light is specularly reflective member 6.
The light that is specularly reflected by the surface of the housing 1 and is also reflected by the surface of the housing 1 that is opposite to the surface of the housing 1 that can enter the field of view of the magnifying glass 7 that is provided orthogonal to the top surface of the housing 1 faces the magnifying glass 7. Since only the light reflected almost at right angles to the bottom surface of the magnifying glass 7 is reflected by the member 6 in the sample chamber 13 whose inner surface is specular, even if the specular reflection is repeated several times. It hardly enters the visual field, and therefore, in the dark field of the magnifying glass 7, the floating dust illuminated by the light beam 5 could be observed as a clear bright spot.

Next, FIG. 2 is a view showing another embodiment of the present invention, in which the inside of the cylindrical housing 1 is divided by a partition plate 12 having circular slits 4 as in FIG. The light from the lamp 2 provided on the right side of the partition is condensed by the condenser lens 3 and is incident on the sample chamber 13 on the left side, and the condensing point of the condensed light beam 5
A magnifying glass 7 that accommodates 14 in the visual field is provided on the side surface of the sample chamber 13.

A plate 18 having a hole 17 for cutting the reflected light on the surface 16 is provided between the condensing point 14 in the sample chamber 13 and the surface 16 facing the light beam 5, and the inner surface of the sample chamber 13 is specularly reflected. For this reason, the entire surface is painted black.

Also in this example, no bright portion due to the reflected light of the light beam 5 was observed in the field of view of the magnifying glass 7, and the suspended dust in the sample chamber 13 was observed as a clear bright spot in the dark field.

Particularly, in this embodiment, since the plate 18 having the hole 17 blocks the primary reflected light of the light beam 5 on the surface 16, the darkness of the field of view of the magnifying glass 7 is almost perfect.

(G) Effect of the device As described above, the dust visual inspection device of the present invention has a simple structure and is easy to handle compared to the dust detection device using the scattered light method or the weight method, and therefore compared to these conventional devices. Suitable for portable dust detection.

Further, in the dust visualizing apparatus of the present invention, the inner surface of the sample chamber 13 which is within the field of view of the magnifying glass 7 does not become bright due to scattered light due to diffused reflection, so that even if the incident light is not completely absorbed by the illuminated surface, The darkness in the field of view is not diminished, so the dust can be seen much more clearly than in conventional devices.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention, FIG. 2 (a) is a view showing another embodiment of the present invention, and (b).
FIG. 3 is a sectional view of FIG. 1 ... Casing, 2 ... Lamp 3 ... Condensing lens 4 ... Slit 5 ... Luminous flux, 6 ... Light absorbing member 7 ... Magnifying glass, 8 ... Sample inlet 9 ... Observation port, 10 …… Eyepiece 11 …… Objective lens, 12 …… Partition plate 13 …… Sample chamber, 14 …… Convergence point 15 …… Opening / closing lid, 16 …… Side 17 …… Hole, 18 …… Plate 19 …… Front Part housing, 20 …… Rear housing 21 …… Sample inlet

Claims (1)

[Scope of utility model registration request] 1. A partition plate having a slit 4 inside the housing 1.
Partitioned by 12, the lamp 2 and the condenser lens 3 are provided on one side, the light of the lamp 2 is condensed on the other side through the slit 4 to form the sample chamber 13, and the dust floating at the condensing point is sampled. Room
In the dust visual observation apparatus for observing with a magnifying glass 7 provided on the wall surface of 13, the dust visual observation apparatus is characterized in that the inner wall of the sample chamber 13 is formed of a specular black member.