JPH0784060A - Filter sheet holder, dust collector using the holder and protective cover of the holder - Google Patents

Abstract

PURPOSE:To efficiently serve a dust monitor system by a filter sheet holder in which a filter sheet is easily replaced, a dust collector having a sealing mechanism of a code at a sampling position, and a protective cover of the holder used also as detaching and attaching means from and to the collector. CONSTITUTION:A filter sheet holder 1 comprises a cap 3 having a sealing region for containing a filter sheet 4, and a holder 2 rotatably engaged with the cap 3. Sealing means 5 for sealing a code added to a dust collector is provided at the cap 3 of the holder 1 when the holder 1 is mounted at the collector to be blocked. A protective cover of the holder 1 for collecting dusts has a base 13 for covering a dust surface of the sheet, and a push-fit socket 14 for holding a U-shaped base 13 from a central back surface of the base 13 for holding the cap 3 of the holder 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust monitor for collecting dust floating in the air in a facility for handling radioactive substances, and measuring the radioactivity concentration after collecting or concentrating the dust. The present invention relates to a filter paper holder to be used, a dust collector using the filter paper holder, and a protective cover for the filter paper holder.

[0002]

2. Description of the Related Art In a dust monitor for monitoring and measuring the presence or absence of radioactive substances in dust floating in the air of a facility handling radioactive substances, the air of the facility to be monitored is shown in FIG. , A dust collector 11 installed in the flow path of the sampler
Dust is collected on the filter paper attached to the, and the radiation from the radioactive substances in the dust captured on the filter paper is measured using the radiation measuring device 18 during the collection operation and after the collection operation for a certain period. Measures the types and amounts of radioactive substances in the facility air.

When the facility to be monitored is large-scale and samplers are installed at many points for monitoring and measurement, a large number of filter paper samples that collect dust are generated, and the filter paper samples are collected after the end of the dust collection period. When measuring with a radiation measuring instrument, each filter paper sample should be coded with the sample air suction point and other sample sampling conditions, and the sampling condition symbols should correspond to the measurement result data. Need to record.

As described above, when dust is repeatedly collected at a number of measurement points under different conditions to measure radioactivity,
A filter paper holder provided with a recording means as disclosed in JP-A-3-144376 has been conventionally used for the purpose of recording sampling conditions and facilitating replacement and mounting of filter paper. FIG. 9 is a diagram illustrating the configuration of the filter paper holder of the above-described conventional example, and a conventional technology example will be described below with reference to this figure.

FIG. 9A is a perspective view of a conventional filter paper holder 15, and FIG. 9B is a perspective view of the filter paper holder 15 before the filter paper 4 is attached to the filter paper holder. A rewritable card-type memory 16 is built in the filter paper holder 15. The card 16 stores the dust collection information and the measurement data, and the stored dust collection information and the measurement data are appropriately stored. Transfer it to the central controller and use it for radiation control.
By clearing the contents of the memory in the card 16 when updating the filter paper 4, the filter paper holder 15 can be used repeatedly.

A door 17 for opening and closing the holder 17 of the filter paper holder 15
By installing a, it becomes possible to pull out the filter paper 4 by closing the door 17a and holding the filter paper 4 when replacing and mounting the filter paper 4 and opening the door 17a when removing the filter paper 4. There is.

[0007]

The above-mentioned conventional filter paper holder provided with a card-type memory can flexibly deal with the need to rewrite the recorded contents, but since it holds the card-type memory. However, the price is high, and the size of the filter paper holder is large, so that a large storage space is required when storing a large number of filter paper holders.

On the other hand, in the case where a large number of measurement points are routinely repeatedly sampled, the conditions for sampling are set in advance for each measurement point, and there is no need to change the conditions for each normal measurement. In many cases, it is sufficient to record only the measurement points for the collected samples. Rather, when the operator handles a large number of filter paper holders that collect dust for the purpose of measuring radioactivity, the construction is such that the radioactive substances collected on the filter paper are not touched and contaminated. desirable.

The present invention is a small-sized filter paper suitable for application to a gas sampler dust collector of a dust monitor measuring system in which measurement data is classified and recorded according to the classification of sampling points, and having a region for writing a symbol of a sampling point of a sample. A filter paper holder that is easy to replace and a collection device that has a sampling point recording means that automatically records the code of the sampling point attached to the dust collector on the filter paper holder when the filter paper holder is attached to the dust collector. Remove the dust collector and the filter paper holder that has already collected dust from the dust collector without touching it directly with the dust collector, and use the protective cover of the filter paper holder that also serves as a means for attaching and detaching the filter paper holder from the dust collector. It is provided to enable efficient operation of a dust monitor system that handles a large number of samples.

[0010]

[Means for Solving the Problems] To achieve the above object,
In the invention of claim 1, the filter paper holder for holding the filter paper mounted on the dust collector of the dust monitor is provided with a concave portion having a diameter capable of accommodating the filter paper on one surface, and has a diameter smaller than that of the filter paper on the other surface. A cap that holds the cylindrical filter paper provided with a small opening penetratingly fits into the recess of the cap, and a plurality of through holes are provided in a mesh shape at the portion where the filter paper abuts. Two places that divide the outer circumference of the holder that fits with the cap described above, and a holder for tightening the filter paper, which is provided on the surface opposite to the contact surface with a recess having a diameter smaller than that of the filter paper. A guide that guides the small convex part of the holder linearly in the fitting direction first and then in a spiral direction in the direction orthogonal to the fitting direction on the inner peripheral part that fits with the holder of the cap. A groove shall be provided.

According to the second aspect of the invention, an area for recording a code attached to the dust collector on which the filter paper holder is mounted is provided at the outer edge of the cap of the filter paper holder on which the holder is mounted. I have decided. Next, claim 3
In the invention of claim 1, when the filter paper holder is mounted and closed on the dust collector in which the filter paper holder for sandwiching the filter paper with the cap and the holder fitted to the cap is mounted, the holder of the cap of the filter paper holder is mounted. The outer edge on the side of the dust collector is provided with marking means for marking the code attached to the dust collector.

Further, in the invention of claim 4, the protective cover of the filter paper holder for sandwiching the filter paper by the cap and the holder fitted to the cap is provided on the base side for covering the dust collecting surface of the filter paper from the cap side of the filter paper holder. It is provided in a U-shape from the center back surface of the base so as to hold this base, and when it comes into contact with the cap and is pressed, it spreads to the outside of the cap and passes through the outer edge portion of the cap, A flexible push hook made of an elastic member having a hook taper portion that contracts and contracts when the contact with the outer edge portion is released. In the invention of claim 5, the push cover is provided on the protective cover of the filter paper holder. A part of the back of the push hook of
It is supposed to be formed in a convex button part that fits into the concave part of the holder.

[0013]

In the filter paper holder composed of only two elements, the cap and the holder, the filter paper is placed in the concave portion of the cap so that the guide groove provided in the cap fits the small convex portion provided in the holder. When abutting and operating the holder to rotate along the guide groove, the filter paper is airtightly sandwiched between the cap and the holder.

Further, the filter paper held in the filter paper holder is taken out from the filter paper holder by the reverse operation of the above. When the filter paper holder holding the new filter paper is attached to the dust collector equipped with the marking means and closed, the code attached to the dust collector is automatically added to the recording area provided on the cap of the filter paper holder. It is imprinted.

When the dust collector is finished and the filter cover is abutted and pressed against the filter paper holder mounted with the dust collector opened, the push hook constituting the protective cover is attached to the outer edge of the cap of the filter paper holder. When it spreads outward and the hook taper of the push hook passes through the position of the cap and the contact with the outer edge of the cap is released, the push hook contracts and holds the cap, so the filter paper holder is collected together with the protective cover. It can be taken out from the dust container. The protective cover that holds the ejected filter paper holder is stacked and stored so that the convex button part provided on the back of the push hook and the concave part inside the holder of the filter paper holder fit together. be able to.

When the button portion on the back surface of the push hook of the protective cover is pressed, the filter paper holder held by the protective cover is released from the protective cover by unclamping the filter paper holder by the push hook.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a filter paper holder according to the present invention is shown in FIGS. FIG. 1 is a cross section of the filter paper holder, and FIG. 2A is a perspective view of the filter paper holder. or,
2B is a perspective view in a state where the filter paper holder shown in FIG. 2A is inverted and disassembled.

The structure of the filter paper holder and its assembling method will be described with reference to FIGS. 1 and 2. Filter paper holder 1 is holder 2
When the radioactivity of dust in the air is measured, the air flows from the top to the bottom of FIG. 1, and the radioactive substance is collected by the sampler so that it is stopped by the filter paper 4. It is attached to the dust container. In order to eliminate the twist of the filter paper 4 and to prevent the filter paper from being damaged, the holder 2 is composed of a holding portion 2a for holding the filter paper 4 and a ventilation hole 2b formed in a net shape through which air flows. A recess 2d having a diameter smaller than that of the filter paper is formed on the surface opposite to the contact surface. The holder 2 is provided with small convex portions 2c at two or more locations that equally divide the outer periphery that fits with the cap 3, while the inner peripheral portion of the cap 3 is provided with the holder 2. The small convex portion 2 of the holder 2 relative to the small convex portion 2
Guide grooves 3a and 3b are provided to guide c first in a straight line in the fitting direction and then in a spiral shape in a direction orthogonal to the fitting direction.

In assembling, first, the filter paper 4 is put in the cap 3, and the holder 2 is placed on the cap 3. When mounting, the guide groove 3a of the cap 3 and the small convex portion 2c of the holder 2 are aligned and the filter paper 4 is sandwiched. . After the filter paper 4 is sandwiched by the holder 2 and the cap 3, when the holder 2 is rotated along the guide groove 3b, the holder 2 and the cap 3 move in a direction in which they are more closely contacted with each other, and a surface pressure is applied to the filter paper 4 to provide airtightness. It is made of a structure that keeps.

When removing the filter paper 4, the filter paper 4 is taken out by performing the reverse operation to the above. Next, one embodiment of a stamping mechanism for imprinting a code on the dust collector having the filter paper holder mounted on the outer edge of the cap of the filter paper holder 1 will be described with reference to FIGS. 3 and 4.

FIG. 3 shows the above filter paper holder 1 according to the present invention.
FIG. 5 is a diagram for explaining a dust collector of the gas sampler to which is mounted and its peripheral portion, and FIG. 4A is a diagram for explaining the operation of the stamping mechanism provided in the dust collector. The structure of the stamp is shown in (b) of FIG. As shown in FIG. 3, the dust collector holds the dust collector fixing portion 11a provided with the radiation detector 18 and fixed to the pedestal, and the filter paper holder. It is constituted by a dust collector movable part 11b which is provided so that its opening can be moved relative to the container fixed part 11a. Then, the output signal of the radiation detector 18 provided in the dust collector is amplified and measured by the measuring unit 19, and the flow rate of the gas passing through the dust collector portion is measured by the flow meter 20.

The stamping mechanism is composed of the movable portion 11 of the dust collector.
As shown in FIG. 4A, the filter paper holder mounting portion 11c of b is disposed so that the outer edge portion of the cap 3 of the filter paper holder 1 on the holder mounting side is imprinted. The stamping position described above is used at the time of mounting / dismounting the filter paper holder 1 to / from the dust collector and mounting / dismounting the filter paper holder 1 after dust collection to / from a radiation measuring device for measuring radioactivity. It is selected because it is difficult for the person to touch.

The stamp 5 of the stamping mechanism is connected to a link mechanism that interlocks with the opening / closing operation of the dust collector movable part 11b through the arm 9, and a filter paper holder is mounted by this link mechanism to move the dust collector movable part 11b. In the action of closing
The stamp 5 stamps the filter paper holder 1 for a moment, and when the movable portion 11b of the dust collecting portion is completely closed, the stamp 5 is attached to the filter paper holder 1
Works away from. By this operation, the stamp surface 6 of the stamp 5 does not remain pressed against the filter paper holder during the entire period when the filter paper holder is attached to the dust collector, so that the stamp surface 6 can be prevented from being deformed.

The stamp 5 is composed of a marking surface 6 on which a code is attached to a dust collector provided with this stamp, a sponge (ink tank) 7 impregnated with ink, and a base 8. The stamp surface 6 is made of a porous rubber material having small holes so that marking can be performed repeatedly. The ink impregnated in the sponge 7 serving as an ink tank enables the filter paper holder 1 to be used repeatedly, so that when printed on the filter paper holder, it can be wiped with cloth or paper to erase the ink. There is.

Next, FIG. 5 and FIG. 6 show an embodiment of the protective cover according to the present invention which is used when the filter paper holder 1 is removed from the movable part 11b of the dust collector and collected.
Explained by. In FIG. 5, (a) shows the protective cover 12.
And (b) is a side view. FIG. 6A
FIG. 6 is a view for explaining the structure of the protective cover in a state where the filter paper holder 1 is held, and is a view corresponding to the AA ′ cross section in FIG. 5. And FIG.6 (b) is a perspective view of a protective cover.

As seen in FIG. 6, the protective cover 12 is
The base 13 that covers the dust collecting surface of the filter paper of the filter paper holder 1 and the elastic member that holds the base 13 in a U-shape from the center back surface of the base 13 that holds the cap 3 of the filter paper holder 1 have flexibility. And the push hook 14 formed on the. When the worker uses the protective cover 12 to remove the filter paper holder from the dust collector 11, open the movable portion 11b of the dust collector,
When the protective cover 12 is covered from above the filter paper holder 1 and the protective cover 12 is lightly pressed, the protective cover 12 and the filter paper holder 1 are combined, and when the protective cover 12 is pulled up, the filter paper holder 1 is pulled out from the dust collector together with the protective cover 12. Be done.

The operation when the protective cover 12 and the filter paper holder 1 are joined together will be described with reference to FIG. When the protective cover 12 is placed on the upper part of the filter paper holder 1 and the protective cover 12 is lightly pressed down, the hook taper portion 14a of the push hook 14 formed by the elastic member to have flexibility is attached to the flange of the cap 3 of the filter paper holder 1. The parts come into contact with each other, and when pressed, the hook part 14b of the push hook 14 is bent so as to spread to both sides around the fulcrum 14e, and the filter paper holder 1 is protected
Inserted to the specified position in the back of 12, hook taper part 14a
When passes through the position of the cap 3, the hook portion 14b of the push hook 14 returns to its original shape as shown in FIG. 6, and the hook portion 14b of the push hook 14 holds the filter paper holder 1.

When the filter paper holder 1 is removed from the protective cover 12, when the button 14c of the push hook 14 is pressed, the hook portion 14b of the push hook 14 bends so as to rotate around the fulcrum 14d, and the two hook portions 14b are separated. When opened to the outside, the filter paper holder 1 is dropped by gravity and separated from the protective cover 12. The button 14c provided on the back surface of the push hook 14 so as to have a convex shape has a size and shape that fits into the recessed portion 1d in FIG. 1 provided on the back surface of the holder 2 of the filter paper holder 1. Since it is formed, the protective cover 12 that holds the filter paper holder 1 and another protective cover 12 that also holds the filter paper holder 1 can be stably stacked on each other.

[0029]

The filter paper is sandwiched between the cap and the holder that fits in the cap in a twisting manner, and the outer edge portion of the cap is provided with a marking area assigned with the code assigned to the dust collector to which the filter paper holder is mounted. According to the filter paper holder of the present invention including two parts, the filter paper holder can be downsized and simplified at a low price, the filter paper can be easily replaced, and necessary information can be stamped on the filter paper holder. It is possible.

Further, if the dust collector to which the filter paper holder is attached is provided with the printing mechanism according to the present invention, when the filter paper holder is attached to the dust collector, the measurement point automatically assigned to the dust collector is installed. Since the code for distinguishing the code is imprinted on the outer edge of the cap of the filter paper holder, it is not necessary to manually write the code. Further, when the filter paper holder after dust collection is detached from the dust collector, if the protective cover according to the present invention is used, it can be detached without touching the filter paper holder, and the dust collection surface of the filter paper remains on the cover after detachment. Since it is covered, even if the radioactive material is collected on the filter paper, there is no risk of the operator touching the radioactive material. Then, the filter paper holders can be stacked together with the protective cover so that the convex button part provided on the back surface of the push hook of the protective cover and the inner circle part of the inner holder of the filter paper holder fit together. Moreover, there is an effect that it does not require a space for storage and can be stably carried out.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a filter paper holder according to the present invention.

FIG. 2 is a perspective view illustrating the configuration of the filter paper holder in FIG.

FIG. 3 is a perspective view of a dust collector of a sampler to which a filter paper holder according to the present invention is attached and its peripheral portion.

4 is an enlarged explanatory view of a filter paper holder mounting portion of the dust collector shown in FIG. 3;

FIG. 5 is an explanatory view of an embodiment of a protective cover according to the present invention.

FIG. 6 is an explanatory diagram for explaining the relationship between the protective cover and the filter paper holder in FIG.

FIG. 7 is an explanatory diagram for explaining the operation when the filter paper holder is removed from the protective cover.

FIG. 8 is a system diagram of a gas sampler equipped with a dust collector.

FIG. 9 is a perspective view of a conventional filter paper holder having a dust collection condition recording unit.

[Explanation of symbols]

 1 Filter paper holder 2 Holder 3 Cap 4 Filter paper 5 Stamp 10 Dust collector and its peripherals 11 Dust collector 11a Dust collector fixed part 11b Dust collector moving part 12 Protective cover 13 Base 14 Push hook 15 With memory Conventional filter paper holder 16 Card type memory 18 Radiation detector 20 Flow meter 22 Flow rate adjusting valve 24 Pump 25 Motor

Claims (5)

[Claims] 1. A filter paper holder for holding a filter paper mounted on a dust collector of a dust monitor, wherein one surface is provided with a recess having a diameter capable of accommodating the filter paper, and the other surface has a diameter smaller than that of the filter paper. A cap for holding the cylindrical filter paper, which is provided with a small opening penetrating through it, and a plurality of through-holes, which meshes with the concave portion of the cap and meshes with the filter paper, are provided in the portion where the filter paper abuts. A holder for tightening the filter paper, in which a recess having a diameter smaller than that of the filter paper is provided on the surface opposite to the contact surface, and the outer periphery of the holder that fits with the cap is equally divided 2
Small convex portions are provided at more than one place, and the small convex portion of the holder is linearly first in the fitting direction on the inner peripheral portion of the cap that fits with the holder, and then in the direction orthogonal to the fitting direction. A filter paper holder having a guide groove for guiding in a spiral shape. 2. An area for recording a code attached to a dust collector to which a filter paper holder is attached is provided on an outer edge portion of the cap on which the holder is attached. The described filter paper holder. 3. A dust collector comprising a cap and a holder fitted to the cap, wherein a filter paper holder for sandwiching a filter paper is mounted between the cap and the holder, wherein the filter paper holder is mounted and closed. The dust collector is provided with an imprinting means for imprinting a code attached to the dust collector on the outer edge portion of the cap on the side where the holder is mounted. 4. A protective cover for a filter paper holder that holds a filter paper between a cap and a holder fitted into the cap, the base covering the dust collecting surface of the filter paper from the side of the cap, and the center of the base. It is provided in a U-shape from the back so as to embrace this base, and when pressed, spreads to the outside of the cap, passes through the outer edge of the cap, and is released from contact with the outer edge of the cap. A protective cover for a filter paper holder, comprising: a flexible push hook made of an elastic member, which is provided with a hook taper portion that contracts and closes. 5. The protective cover for a filter paper holder according to claim 4, wherein a part of the back surface of the push hook is formed into a convex button portion that fits into the concave portion of the holder.