JPH0561597B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sample holder used in a radioactivity measuring device for investigating air contamination and surface contamination by radioactive substances.

[Conventional technology]

FIG. 4 is a diagram showing an automatic sample exchange type radioactivity measurement device, in which 10 is a sample holder, 11 is a counting display section, 12 is an automatic sample exchange measurement section and detection section, 13
1 is a printer, 14 is a first sample chamber, 15 is a second sample chamber, and 16 is an operating section.

An automatic sample exchange type radioactivity measurement device, which is an example of a radioactivity measurement device, is composed of a count display section 11, an automatic sample exchange measurement section, a detection section 12, a printer 13, etc. This is a device that measures radioactivity by attaching a holder 10.

The automatic sample exchange measurement section and detection section 12 includes a first sample chamber 14, a second sample chamber 15, and a lower operation section 16, each of which can store up to 30 samples in the sample holder 10 before and after radioactivity measurement. It consists of 3 to 4 units consisting of:

A dusty filter paper is attached to the sample holder 10, and a maximum of 30 samples are stored in the first sample chamber 14.
The sample holders 10 at the bottom are automatically taken out to the detection section in sequence, radioactivity is detected, and the sample holders 10 after the measurement are transferred to the second sample chamber 15. Detection is performed simultaneously for three to four units of sample holders 10 in the automatic sample exchange measurement section as necessary.

The radioactivity measurement results are displayed on the count display section 11 and recorded on the printer 13, and the radioactivity concentration is calculated.

FIG. 5 is a diagram showing the procedure for attaching a filter paper to a conventional sample holder. In the figure, 20 is a filter paper, 21 is a sample plate, and 2
2 is a ring, 23 is a pair of tweezers, and 24 is a fingertip.

The filter paper 20 has a circular shape, and the sample tray 21 is made of stainless steel, has an inner diameter slightly larger than the outer diameter of the filter paper 20, allows the filter paper 20 to be inserted from above, and has a depth slightly larger than the thickness of the filter paper 20. ing. The sample holder 10 is a circular plate provided with a stage on which a ring 22 for holding a sample plate 21 and a filter paper 20 is placed from above.

A filter paper 20 adhering to radioactivity by adsorbing dust in the air is put into a sample dish 21 using two tweezers 23 or a gloved fingertip 24 and the tweezers 23, and then placed in the sample holder 10. Generally, filter paper is bent by the humidity in the air, so it is pressed with ring 22 to keep it flat and to prevent sample plate 21 and filter paper 20 from flying out.

In this way, a large number of sample holders 10 with the filter paper 20 attached are housed in the first sample chamber 24, and radioactivity is measured.

[Problem to be solved by the invention]

In this way, conventional sample holders require a ring to hold down the sample plate and filter paper in addition to the sample holder, which makes them too heavy for smooth automatic sample exchange measurements in the detection unit, and the number of sample holders with filter paper attached is too heavy. will be reduced to about 20. In addition, filter paper is easily deformed at everyday temperatures, and in the case of deformed filter paper, it is difficult to fit the filter paper into the sample dish, and it takes time to attach the filter paper, resulting in pressing the potentially contaminated filter paper with one's fingers. Furthermore, when measuring deformed filter paper, the filter paper may get caught in the measuring device.
There is a drawback that the measuring device automatically stops.

The present invention is intended to solve the above problems,
Even deformed filter paper can be easily and quickly attached directly to the sample holder without using a sample plate or ring, and radioactivity can be efficiently measured without the filter paper getting caught in the measuring device during measurement. The object of the present invention is to provide a sample holder for a radioactivity measuring device that can be used as a radioactivity measuring device.

[Means to solve the problem]

To this end, the sample holder for a radioactivity measurement device of the present invention has a filter paper storage space formed in the center of the front surface with an opening diameter smaller than the diameter of the filter paper and a groove for attaching the filter paper around the bottom surface. It is characterized by having a slit-like opening for putting in and taking out the filter paper at the same height on the side.

[Effect]

The present invention provides a sample holder for filter paper by providing a groove for inserting the filter paper in the bottom of the inner wall of the sample holder, which is composed of a cylindrical annular side wall, an outer diameter of the side wall, and a disk-shaped bottom, and a groove for taking the filter paper in and out from the outside. makes it easy to install.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the sample holder for a radioactivity measuring device according to the present invention, in which figure A is a plan view and figure B is a plan view.
2 is a side sectional view, FIG. 2 is a perspective view of the sample holder and filter paper of the present invention, and FIG. 3 is a diagram showing the procedure for attaching the filter paper to the sample holder of the present invention. In the figure, the same numbers as in FIG. Shows the same content. 1 is a sample holder, 2 is a filter paper storage space, 3 is a mounting groove, 4 is a slit-shaped opening, 5 is a flange, 6 is a notch, 7 is an operating hole, and 8 is a knob.

In the figure, sample holder 1 is made of ABS resin.
A filter paper storage space 2 having an opening is formed at the center of the front surface. The opening diameter of the filter paper storage space 2 is smaller than the diameter of the filter paper, and a mounting groove 3 having a slightly larger diameter than the filter paper is provided around the bottom of the filter paper storage space. Further, a slit-like opening 3 for taking in and taking out the filter paper is provided at a side position at the same height as the bottom surface of the filter paper storage space. Further, a flange portion 5 is provided at the top of the sample holder, and a semicircular notch 6 that reaches the slit-shaped opening 4 is provided in a part of the flange portion 5 to make it easy to see the position of the slit-shaped opening 4 and to take out the filter paper. I'm trying to make it easier. Further, a hole 7 for operation is provided in the center of the filter paper storage space 2, and is used for moving and fixing the sample holder 1 within the automatic sample exchange measurement section.

To attach the filter paper to the sample holder having such a configuration, as shown in FIG.
3 and insert it into the filter paper storage space 2 through the slit-shaped opening 4 on the side, and feed it all the way with the tweezers 23 and attach it to the mounting groove. Since the opening diameter of the storage space is smaller than the diameter of the filter paper, even if the filter paper is bent, it can be firmly held by mounting it in the mounting groove. The sample holder held in this manner can be housed in an automatic sample exchange type radioactivity measuring device to measure radioactivity.

Further, the filter paper can be easily removed from the sample holder by first pushing out the filter paper with tweezers, and when the tip of the filter paper reaches the position of the notch 6, gripping and pulling it out.

Note that the filter paper used to investigate the radioactivity of surface contamination is attached with a knob 8 as shown by the dotted line in Figure 2. Hold this knob 8, store it in the sample holder, and cut off the part with the knob 8. , the radioactivity concentration is measured in the same way as for air pollution.

〔Effect of the invention〕

As described above, according to the present invention, the filter paper can be easily attached to the sample holder using tweezers, and as an example, the conventional attachment time for a set of 90 sample holders, which was about 31 minutes, can be shortened to about 18 minutes. Ta. Since the deformed filter paper can be mounted flat, there are no troubles during measurement and there is no need for re-measurement time.
Furthermore, it is possible to reduce the number of parts due to the use of non-flammable sample plates and rings, eliminate the time required to sort non-flammable materials, reduce economic efficiency, and shorten work time for post-processing.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the sample holder for a radioactivity measuring device according to the present invention, in which figure A is a plan view and figure B is a plan view.
is a side sectional view, FIG. 2 is a perspective view of the sample holder and filter paper of the present invention, FIG. 3 is a diagram showing the procedure for attaching the filter paper to the sample holder of the present invention, and FIG. 4 is an automatic sample exchange type radioactivity FIG. 5 is a diagram showing a measuring device and a diagram showing a procedure for attaching a filter paper to a conventional sample holder. 1... Sample holder, 2... Filter paper storage space, 3...
...Mounting groove, 4...Slit-shaped opening, 5...Flange portion, 6...Notch, 7...Operation hole, 8...Knob.

Claims (1)

[Claims of Claims] 1. A filter paper storage space is formed in the center of the front surface with an opening diameter smaller than the diameter of the filter paper and a groove for installing the filter paper on the circumferential surface of the bottom surface, and the side surface is located at the same height as the bottom surface of the storage space. A sample holder for a radioactivity measuring device, characterized in that a slit-like opening for inserting and removing filter paper is provided in the holder. 2. The sample holder for a radioactivity measuring device according to claim 1, wherein the uppermost portion of the holder has a large diameter and forms a flange portion. 3. The sample holder for a radioactivity measuring device according to claim 1 or 2, further comprising a notch extending from the periphery of the top of the holder to the slit-shaped opening.