JPH0539502Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a radiation detection device used in a whole body counter, etc. used for detailed inspection of the presence or absence of radioactive substances absorbed into the human body, which is particularly easy to handle and The present invention relates to a configuration in which main parts can be made compact.

[Prior art and its problems]

In facilities that handle radioactive materials, each time a person leaves the facility, their clothes are inspected for the presence of radioactive materials, but in addition to these tests, there is a In some cases, detailed examinations are conducted that focus on testing for the presence or absence of radioactive substances that have been absorbed into the human body or that have been absorbed into the human body. Such detailed examinations are usually performed with the human body being examined supine, and the examination is usually performed using a whole body counter.

FIG. 2 is a configuration diagram of the conventional whole body counter described above. In the figure, 1 is a bed 3 on which a human body 2 to be examined lies supine, which is supported by a mechanism not shown so that the bed can move horizontally. This is the frame. The frame 1 is installed on the floor, and is provided with a radiation shielding member to prevent radiation from the floor from entering the detector. Reference numeral 4 denotes a rectangular parallelepiped-shaped bottomed container made of a radiation shielding material. 5 and 6 are installed so as to be lined up in the longitudinal direction of the human body 2. The radiation incident surfaces 5a, 6a of both the detectors 5, 6 are directed toward the human body 2. The detector 5 is a detector installed on the head side of the human body 2, and is a detector that detects whether or not there is a radioactive substance in the human body 2. The detector 6 is a detector that detects the nuclide of the radioactive substance that emits radiation. It is a vessel. Reference numerals 7 and 8 denote lids made of a radiation shielding material that completely cover the opening end 4a of the container, and both lids 7 and 8 are fitted along the opening end 4a by a mechanism not shown. It is configured to be movable. Since the lids 7 and 8 are constructed in this manner, by appropriately moving both lids, it is possible to form a radiation entrance to the radiation entrance surface 5a or 6a of the detector. Reference numeral 9 in the figure indicates that by moving the lid members 7 and 8 as described above, the lid member 7 and the detector 6 can be removed.
This is a radiation entrance opening for the radiation entrance surface 5a formed by a lid member 8 disposed so as to shield radiation incident on the radiation entrance surface 6a. The lid materials 7 and 8 are used as the radiation detectors 5 and 6 as described above.
Since the direction of incidence of each radiation on the radiation entrance surfaces 5a, 6a of the detector is limited by forming a radiation entrance for the detector, both lid members 7,
8 forms a collimator for the radiation incident on the detectors 5 and 6. Therefore, the lid members 7 and 8 may be referred to as collimators hereinafter.
The radiation shielding member provided in the frame 1 described above is
Radiation emitted from sources other than the human body 2 is detected by the detectors 5 and 6.
It is designed so that it cannot be detected by. Reference numeral 10 denotes a radiation detection device consisting of the illustrated parts except for the frame 1 and the bed 3.

In Fig. 2, first, with the open end 4a of the container closed with the lids 7, 8, the bed 3 is moved so that the part of the human body 2 to be examined is located directly under the detector 5, and then the lids 7, 8 are moved to form a radiation entrance 9, and the presence or absence of radioactive material in the human body 2 is examined by the detector 5. If the presence of radioactive material is detected in this examination, the entrance 9 is closed and the part of the human body 2 in question is moved directly under the detector 6, and the lids 7, 8 are closed again.
2, the radiation detection device 10 in FIG. 2 has a problem that it is difficult to handle because the heavy lids 7 and 8 must be moved together. In addition, in order to form the entrance 9 in FIG. 2, one of the lids 7 or 8 must be protruded to the side of the container 4, and therefore such a radiation detection device 10 requires the lids 7 and 8 to be protruded to the side of the container 4.
There is also the problem that number 8 is large.

[Purpose of invention]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems with conventional radiation detection devices, and to provide a radiation detection device that is easy to handle and whose main parts can be made compact.

[Key points of the idea]

In order to achieve the above object, the present invention includes a bottomed container made of a radiation shielding material, a plurality of radiation detectors installed in a line inside the container, and each of which partially covers the open end of the container. A radiation detector is constituted by at least one movable lid made of a radiation shielding material arranged in a row and two fixed lids made of a radiation shielding material placed on both outermost sides of the movable lid, and the radiation detector is further movable. Each lid member is configured to form a radiation entrance port for any one of the radiation detectors between adjacent lid members by moving the lid member along the open end of the bottomed container, With this configuration, it is possible to obtain a radiation detection device in which the movable lid material is easy to handle and the lid material of the bottomed container can be formed into a small size.

[Example of idea]

FIG. 1 is a block diagram of a whole body counter employing an embodiment of the present invention. The difference between this figure and FIG. 2 is that one movable lid member 11 made of radiation shielding material
and two fixed lid members 12 and 13 made of radiation shielding material placed on both sides of the lid member 11. Each of the lids 11 to 13 is configured to partially cover the open end 4a of the container 4, and the lid 11 is configured to be movable along the open end 4a. 14 is a container 4 and radiation detectors 5 and 6
This is a radiation detection device comprising: and lid members 11 to 13. In this detection device, by moving the lid material 11 along the opening end 4a, the lid materials 11 and 12 are
Each cover member is configured such that a radiation entrance opening for either the detector 5 or 6 is formed between the cover members 11 and 13 or between the cover members 11 and 13. In the figure, the lids 11 and 12 form a radiation entrance 9 for the detector 5, and in this case, the radiation incident on the detector 6 is blocked by the lids 11 and 13. In the radiation detection attachment 14, the lid material 1
1 is brought into contact with the lid member 12, the lid members 11 and 13 form a radiation entrance port for the radiation detector 6.

In FIG. 1, the radiation detection device 14 is configured as described above, so when performing a radioactivity test on the human body 2 using this device 14, the movable lid 11 is placed between the lids 12 and 13. All you have to do is move it. Therefore, in such a radiation detection device, compared to the device 10 shown in FIG. 2 in which the two movable lid members 7 and 8 must be moved,
The movable lid material is easy to handle. In addition, in the detection device 14, since the movable lid 11 does not protrude to the side of the container 4, the total size of the lids 11, 12, and 13 is equal to the size of the lids 7 and 8 in FIG.
It is clearly smaller than the total size of the lid material. Therefore, in the detection device 14, the lid member and its support mechanism can be made smaller than in the case of FIG.

In the above embodiment, since two detectors 5 and 6 are installed inside the container 4, only one movable lid member 11 is required.
However, the present invention is not limited to such an embodiment, and three or more radiation detectors may be arranged in parallel in the container 4,
In this case, a plurality of movable lid members will naturally be juxtaposed between the two fixed lid members. It is obvious that the present invention may be used in devices other than whole body counters.

[Effect of idea]

As described above, in the present invention, in a radiation detection device including a bottomed container made of a radiation shielding material and a plurality of radiation detectors installed in a line inside the container, each of the radiation detectors partially covers the open end of the container. At least one movable lid member arranged in a line so as to cover the target, and two fixed lid members placed on both outermost sides of this movable lid member, each of which is made of radiation shielding material. In addition, by moving the movable lid along the open end of the bottomed container, a radiation entrance opening for any one of the radiation detectors is formed between adjacent lids. Therefore, in the present invention, since the movable lid does not protrude to the side of the bottomed container and is moved, the entire lid including the movable lid and the fixed lid can be made smaller than in conventional radiation detection devices. There is an effect that can be formed. In addition, in the present invention, since the fixed lid material is not moved when forming the radiation entrance port,
Another advantage is that the movable lid material is easier to handle than conventional devices.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a whole body counter employing an embodiment of the present invention, and FIG. 2 is a block diagram of a whole body counter using a conventional radiation detection device. 4... Container, 5, 6... Radiation detector, 7,
8, 11...Movable lid material, 9...Radiation entrance port, 1
0, 14... Radiation detection device, 12, 13... Fixed lid material.

Claims (1)

[Scope of utility model registration request] A bottomed container made of a radiation shielding material, a plurality of radiation detectors arranged side by side within the container and detecting radiation incident from outside the container, each arranged side by side so as to partially cover an open end of the container. at least one movable lid made of a radiation shielding material and two fixed lids made of a radiation shielding material disposed on both outermost sides of the movable lid; A radiation detection device characterized in that a radiation entrance opening for any one of the radiation detectors is formed between the adjacent lid members by moving the container along an open end.