JP3003244B2 - Dust sampler - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to dust used for monitoring radioactive substances in the atmosphere by collecting dust in the atmosphere and examining radiation radiated from the collected dust. The present invention relates to a sampler, and more particularly to a sampler that is easy to manufacture and maintain.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of a conventional dust sampler 1. In the figure, reference numeral 2 denotes a rectangular parallelepiped airtight container having a rectangular bottom plate 2a, side walls 2b, and a lid 2c.
Is a thick bottomed cylindrical container made of lead, which is airtightly penetrated on the side wall 2b of the container 2; an inlet, an outlet, and a connector; and 7, a radiation incident window 7a is directed to the opening 3a of the container 3. The container 3 is provided by means not shown via a spacer 8.
Reference numeral 9 denotes a cylindrical radiation detector fixed in the inside. Reference numeral 9 denotes an intake pipe which connects the intake port 4 to the intake port 3b penetrating through the side wall of the container 3 so as to be located in the container 2. . 1
Reference numeral 0 denotes a trumpet-shaped flow path member 11 arranged such that the wide-mouthed portion faces the container opening 3a via a space 13 having a predetermined distance d, and the narrow-mouthed portion of the member 11 and the exhaust port 5 An exhaust passage composed of a connecting pipe 12 and a supply spool 1
5. A ribbon-shaped filter paper wound by a take-up spool 18 supplied by the motor 5 and driven by a motor 16 via a coupling mechanism 17 and positioned across the cavity 13 by being positioned by guide rollers 19, 20 , 21 are micro switches for detecting out of filter paper. In this case, the connector 6 mentioned above is
1. A conductive path (not shown) reaching each of the radiation detectors 7 is provided to penetrate the side wall 2b of the hermetic container 2. Then, in this case, all the above-described parts except the container 3, the intake port 4, the exhaust port 5, and the connector 6 are housed as shown in the container 2 hermetically sealed by the lid 2c. ing.

[0003] Since the dust sampler 1 is configured as described above, when a suction pump is connected to the exhaust port 5 and the pump is operated, the gas guided to the intake port 4 is supplied to the intake port 4, the intake pipe 9, A suction hole 3b, a gap between the container 3 and the detector 7,
The gas, which is exhausted through the container opening 3a, the fine holes of the filter paper 14, the exhaust passage 10, and the exhaust port 5 sequentially, is guided to the intake port 4 by an appropriate means. When the suction pump is operated in this way, the dust in the monitored gas is removed from the filter paper 14 placed in the space 13.
Is collected in the portion 14a. However, in this case, the radiation detector 7 is arranged so that the radiation incident window 7a is near the filter paper portion 14a and faces the portion 14a. Therefore, according to the dust sampler 1, the presence or absence and the amount of the radioactive substance in the monitoring target gas are detected by the detector 7.

[0004]

Since the dust sampler 1 is constructed as described above and almost all the devices are housed in the airtight container 2, the maintenance work on the devices in the container 2 is carried out each time the lid 2c is used. It is necessary to remove
Therefore, the sampler 1 has a problem that maintenance work is troublesome. Further, in the sampler 1, if the airtightness of the container 2 is poor, dust in the air around the container 2 may be collected by the filter paper portion 14a and the monitoring operation of the radioactive substance by the detector 7 may be disturbed. As described above, an airtight mechanism such as a packing for ensuring airtightness between each of the lead container 3, the intake port 4, the exhaust port 5, the connector 6, and the lid 2c and the container side wall 2b is required. Also has a problem that production is troublesome. Therefore, an object of the present invention is to obtain a dust sampler that can be easily manufactured and maintained without using the airtight container 2 described above.

[0005]

In order to achieve the above object, a thick bottomed or bottomed lead cylinder having an intake hole formed in a side wall, a lead body, and a filter paper are provided. And a main body driving mechanism for pressing the opening of the bottomed cylindrical body or one of the open ends of the bottomless cylindrical body through the main body and passing the gas in the cylindrical body through the filter paper to the main body. Each airtightness between the filter paper and the cylinder and between the filter paper and the main body pressed by the filter body by the filter paper pressing part provided with an exhaust passage so that air can be exhausted. An airtight mechanism that secures the airtightness, and is disposed inside the cylindrical body so as to detect radiation emitted from the filter paper pressed against the cylindrical body by the filter paper pressing unit, and the cylindrical body has no bottom. At this time, make sure that the other open end of the bottomless cylinder does not communicate with the intake hole. An airtight mechanism is fixed to the end of the cylindrical body and protrudes from the surface on the filter paper side in the dust sampler so as to include a radiation detector that has been subjected to an airtight processing between the bottomless cylindrical body and the radiation detector. A first member provided with an annular first structure sinking from the surface, and a surface on the side of the cylindrical body fixed around a filter paper side end of an exhaust passage in a main body of the filter paper pressing portion. And a second member provided with an annular second structure that fits with the first structure.

[0006]

With the above arrangement, when a suction pump is connected to the end of the exhaust passage opposite to the filter paper in a state where the filter paper is pressed against the cylinder by the filter paper pressing portion, suction from outside the cylinder is performed. The gas to be monitored guided to the hole is exhausted through the intake hole, the inside of the cylinder, the filter paper, and the exhaust flow path in order, and the dust in the gas is collected on the filter paper. The radiation emitted from the collected dust is detected by a radiation detector to monitor radioactive substances in the gas. In this case, an airtight container as in the above-described conventional dust sampler 1 is required. Obviously, a dust sampler that is easy to manufacture and maintain is obtained.

[0007]

FIG. 2 is a plan view of an embodiment of the present invention. FIG. 1 is a longitudinal sectional side view of a main part in FIG. 2. FIGS. 1 and 2 show the same parts as those in FIG. The same reference numerals are attached. Then, in FIG. 1 and FIG.
Is a bottomed thick cylinder made of lead corresponding to the above-mentioned container 3 and having a suction hole 22a corresponding to the above-described suction hole 3b penetrating through the side wall. In this case, as in FIG. The vessel 7 is fixed in the cylindrical body 22 by means not shown via a spacer 23 corresponding to the above-mentioned spacer 8 such that the radiation incident window 7a is located near the opening 22b of the cylindrical body 22. . Reference numeral 44 denotes a metal first member having a cylindrical portion 44b smaller than the cylindrical opening 22b, and the disk portion 44a is fixed to the cylindrical body 22 with the screw 25 at the opening 22b, and 27 is not shown. This is a bottom body to which the cylindrical body 22 is fixed by means.

Reference numeral 28 denotes a circular stepped concave portion 29a formed on one surface 28a and an exhaust hole 29 formed on the other surface 28b.
b and a thick lead-shaped main body portion 45 provided with an exhaust passage 29 composed of a communication hole 29c connecting the concave portion 29a and the hole 29b, and a lead 45 fixed in the concave portion 29a of the main body 28 by a screw 31. The metal thick annular plate-shaped second member 33 includes a fixed portion 33a fixed to the bottom plate 27 by screws 34, a movable portion 33c inserted into the fixed portion 33a via a bearing mechanism 33b, The gear 3 includes a bearing mechanism 33b and a gear 33d fixed to the movable portion 33c.
When the motor 3 drives the 3d, the movable part 33c rotates, and the screw rod 36 screwed into the movable part 33c moves in the direction of the axis indicated by XX of the rod 36. In the screw rod driving mechanism described above, reference numeral 37 denotes a connecting member in which one end of the screw rod 36 and the main body 28 are fixedly connected.

Reference numeral 38 denotes a slide rail fixed to the bottom plate 27 by means (not shown) such that the main body 28 connected to the screw rod 36 by the member 37 moves smoothly in a predetermined direction as the rod 36 moves. A slide mechanism 39 comprising a slide member 38b fixed to the main body 28 so as to fit on the rail 38a, and a slide mechanism 39 slides between the motor device 35, the screw rod drive mechanism 33, the screw rod 36, the coupling member 37, and the like. This is a main body drive mechanism including the mechanism 38.

Reference numeral 40 denotes a filter paper pressing portion including a main body driving mechanism 39 and a main body 28. In the pressing portion 40, one surface 28a of the main body 28 is directed toward the opening 22b of the cylindrical body 22 through the filter paper 14. The main body drive mechanism 39 is pressed
And the related members are configured so that the filter paper 14 is sandwiched between the first member 44 and the second member 45 as a result of the surface 28a being pressed as described above.
The exhaust passage 29 is configured so that the gas in the cylindrical body 22 can be exhausted through the filter paper 14 with the filter paper 14 sandwiched between the member 44 and the second member 45. The first
An annular groove 44c as a first structure is provided on a surface of the disk portion 44a of the member on the filter paper 14 side, and a second member 45 is provided.
On the surface on the side of the filter paper 14, there is provided an annular projection 45a as a second structure which just fits into the groove 44c.

Reference numeral 43 denotes a dust sampler provided with the components shown in FIGS. 1 and 2.
When the filter paper 14 is sandwiched between the main body 28 and the cylindrical body 22, the airtightness between the filter paper 14 and the cylindrical body 22 and between the filter paper 14 and the main body 28 are improved by the first member 44 and the second member. In this case, the first member 44 and the second member 45 form the pressing portion 40.
Thus, it can be said that the confidential mechanism 46 for ensuring the airtightness between the filter paper 14 pressed by the cylindrical body 22 and the cylindrical body 22 and between the filter paper 14 and the main body 28 is configured.
Therefore, in the sampler 43, the gas to be monitored is guided to the intake port 22 a and the exhaust port 29 is held in a state where the filter paper 14 is sandwiched between the main body 28 and the cylindrical body 22 by the pressing part 40.
b, when the suction pump is connected and the pump is operated, the gas flows into the suction hole 22a, the gap between the cylinder 22 and the detector 7, the cylinder opening 22b, the fine hole of the filter paper 14, the exhaust passage. 2
As a result, dust in the monitored gas is collected by the filter paper portion 14a, and the detector 7 monitors the radioactive substance in the gas.

In the sampler 43, dust is collected as described above. In this case, the airtight container 2 and the air inlet 4, each of which requires airtightness, as in the case of the conventional sampler 1, are provided. Obviously, no vent 5 and no connector 6 are required. Therefore, the sampler 43 is a sampler that is easy to manufacture and maintain. Since the sampler 43 is configured as described above,
It is clear that the sampler 43 is a sampler that is easy to manufacture and maintain. In this case, the airtight mechanism 46 is configured as described above, so that the airtight mechanism is easy to manufacture and the filter paper 14 is not easily attached to the airtight mechanism. There is an advantage.

In the above embodiment, the cylindrical body 22 has a bottom. However, in the present invention, the cylindrical body 22 may have no bottom. In order to ensure that the filter paper 14 is collected, the opening end of the cylinder 22 opposite to the opening 22 b and the intake hole 22 a communicate with each other through the interior of the cylinder 22. Needless to say, an airtight process must be performed between the cylinder 22 and the radiation detector 7 so as not to cause such a situation. Thus, in the sampler 43 described above, the groove 44c is provided in the member 44 and the projection 45a is provided in the member 45. In the present invention, the groove 44c is provided in the member 45 and the projection 45a is provided.
Obviously, a may be provided on the member 44.

[0014]

As described above, according to the present invention, when a suction pump is connected to the end of the exhaust passage opposite to the filter paper side in a state where the filter paper is pressed against the tubular body by the filter paper pressing portion,
The gas to be monitored guided from the outside of the cylinder to the intake hole is exhausted through the intake hole, the inside of the cylinder, the filter paper, and the exhaust passage sequentially, and the dust in the gas is collected on the filter paper. The radiation emitted from the dust collected in this way is detected by the radiation detector to monitor the radioactive substance in the gas. In this case, as in the conventional dust sampler 1 described above, Since it is clear that a simple airtight container is not required, there is an effect that a dust sampler that can be easily manufactured and maintenance work is obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part according to an embodiment of the present invention.

FIG. 2 is a plan view of the embodiment of the present invention, showing a longitudinal sectional side view of a main part in FIG. 1;

FIG. 3 is a diagram illustrating the configuration of a conventional dust sampler.

[Explanation of symbols]

 7 Radiation Detector 14 Filter Paper 22 Cylindrical Body 22a Intake Hole 22b Opening 28 Main Body 29 Exhaust Flow Path 39 Main Body Driving Mechanism 40 Filter Paper Pressing Section 42 Airtight Mechanism 43 Dust Sampler 44 First Member 44c Groove (First Structure) 45th 2 member 45a Projection (second structure) 46 Airtight mechanism

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01T 7/04 G01N 1/02

Claims (1)

(57) [Claims] 1. A bottomed or non-bottomed thick cylindrical body made of lead having an intake hole penetrated in a side wall, and a main body made of lead and an opening of the bottomed cylindrical body through a filter paper. Alternatively, a main body drive mechanism for pressing one open end of the bottomless cylindrical body is provided, and an exhaust passage is provided in the main body so that gas in the cylindrical body can be exhausted through the filter paper. An airtight mechanism for ensuring airtightness between the filter paper pressed by the filter paper pressing section and the cylindrical body by the filter paper pressing section and the cylindrical body, and between the filter paper and the main body; and The other opening of the bottomless cylindrical body is disposed inside the cylindrical body so as to detect radiation emitted from the filter paper pressed against the cylindrical body by the portion and when the cylindrical body has no bottom. Radiation that is hermetically sealed between the bottomless cylinder so that the end does not communicate with the intake hole A dust sampler characterized by comprising a detector, wherein an airtight mechanism is fixed to an end of the cylindrical body, and an annular first member protruding from the surface or sinking from the surface on the surface on the filter paper side. A first member provided with a structure, which is fixed to the periphery of the filter paper side end of the exhaust passage in the main body of the filter paper pressing portion, and fits on the surface of the cylindrical body with respect to the first structure. A dust sampler comprising a second member provided with an annular second structure that fits therewith.