JPH023953B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radiation measuring device for measuring the radioactive contamination state and radioactive distribution state of a working space where radioactive materials may exist, such as a working room of a nuclear power plant. In particular, the present invention relates to a portable radiation measurement device that can simultaneously measure the air dose rate and simultaneously record the air dose rate, the measurement position, and the measurement time in correspondence with the measurement position.

Conventionally, when detecting the state of radioactive contamination and distribution in a work space, a measurement person in the work room carries a radiation measuring device such as a GM tube survey meter and measures the air dose rate at each of numerous measurement points. Measure and record the measurement location, air dose rate, and various conditions such as measurement time on the record sheet you brought with you. Based on this recorded data, create the distribution of air dose rate in the work room. That's what I was doing. however,
According to this measurement method, the work of measuring and writing on a record sheet is repeated for each measurement point, which takes a lot of time and makes the measurement work complicated when measuring over a wide area. The work efficiency is extremely poor, and above all, the radiation exposure of the person being measured increases, which is extremely unfavorable from a safety standpoint.

The present invention has been made to address these points,
A radiation measurement device for measuring radioactivity distribution in a work space, comprising: a radiation detector and a radiation signal processing circuit for measuring the air dose rate at any measurement point; and a measurement time circuit for providing the measurement time. A measurement position detection coordinate unit consisting of a group of signal detection elements arranged in a dimensional matrix, a floor map that is placed in close contact with the measurement position detection coordinate unit and depicts a working space, and a floor map that maps the work space from above the floor map to the signal detection elements. A measurement position indicating pen that provides a signal, an instruction signal input circuit that inputs a signal to the measurement position indicating pen, and a measurement position decoder that decodes the measurement position from the address of the signal detection element that receives the signal in the measurement position detection coordinate section. a data processing circuit that processes signals respectively input from the radiation signal processing circuit, the measurement time circuit, and the measurement position decoding circuit; a recording device that records data from the data processing circuit; and determining measurement timing. The object of the present invention is to provide a radiation measuring device that is equipped with a trigger switch circuit and can simultaneously convert and record data on the air dose rate, measurement position, and measurement time.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows the external appearance of a portable radiation measuring device of the present invention, where 1 is the main body of the measuring device. A radiation detector 2 for measuring the air dose rate at each measurement point in the work space is mounted on the front of the measuring device main body 1.
are integrally attached, and a GM tube survey meter, a scintillation survey meter, an ionization chamber survey meter, a proportional counter tube survey meter, etc. are used as the radiation detector 2.
An indicator meter 3 for displaying the measured value of the air dose rate and a measurement time circuit display section 4 for indicating the measurement time are provided on the top surface of the measuring device main body 1, and a two-dimensional matrix-like display for detecting the measurement position is provided. Measurement position detection coordinate section 5 consisting of an arrayed detection element coordinate group
is installed, and a floor map 6 depicting the work space is superimposed on it. Reference numeral 7 denotes a measurement position indicating pen which provides a signal to the measurement position detection coordinate unit 5 via the indicated point on the floor map 6. A light pen or the like is used as the measurement position indicating pen 7.
Further, 8 is a recording device that stores data on the measurement of the air dose rate, the measurement position, and the measurement time for each measurement operation, 9 is a handle for carrying the measuring device main body 1, and 10 determines the measurement timing. It is a measurement trigger switch.

FIG. 2 is a block diagram showing the circuit configuration of the device shown in FIG. 1. In the figure, 11 is a radiation signal processing circuit that converts the radiation signal obtained by the radiation detector 2 into an air dose rate, and 12 is a measurement time circuit that provides measurement time. Reference numeral 13 denotes an instruction signal input circuit that provides an instruction signal to the measurement position indicating pen 7 in response to a command from the trigger switch circuit 10, and the measurement position indicating pen 7 instructs the signal detection element 14 corresponding to the indicated point on the floor map 6. supply the signal. The signal detection elements 14 are arranged in a two-dimensional matrix and constitute the measurement position detection coordinate section 5. The position coordinates of the signal detection element 14 which has caught the signal from the pointing pen 7 are decoded by measurement position decoding circuits 15a and 15b. 16 is a data processing circuit which converts the data signals input from the radiation signal processing circuit 11, measurement time circuit 12 and measurement position decoding circuits 15a and 15b into digital signals etc. in response to the command from the trigger switch circuit 10. The signal is organized into a predetermined signal format and recorded by the recording device 8.
Output to.

Next, the operation of the radiation measuring device configured as above will be explained.

First, turn on the measurement trigger switch 10 at the measurement location.
Then, the radiation signal obtained by the radiation detector 2 is converted into an air dose rate by the radiation signal processing circuit 11 and sent to the data processing circuit 16, and at the same time, the measurement time signal from the measurement time circuit 12 is also sent to the data processing circuit 16. is input. Further, in response to a command from the measurement trigger switch circuit 10, the instruction signal input circuit 13 gives an instruction signal to the measurement position indicating pen 7, for example, a light pen, to optically turn on the tip of the light pen. When holding the measurement position indicating pen 7 and pointing to the part corresponding to the measurement position on the floor map 6 made of a transparent sheet, a sheet with small holes punched out in a dimensional matrix, etc., the measurement position detection coordinate area 5
The signal detection element 14 directly below the indicated point on the floor map receives the signal from the measurement position indicating pen 7.
It becomes ON state. As this signal detection element, a photodetection element such as a phototransistor is used depending on the form of the input signal. The address of the signal detection element 14 which is in the ON state is decoded by the measurement position decoding circuits 15a and 15b and sent to the data processing circuit 16.

The air dose rate measurement signal, measurement position signal, and measurement time signal input to the data processing circuit 16 in this manner are each converted into a digital signal, etc., and then organized into a predetermined signal format and stored in the recording device 8. . For example, each measurement signal is converted into a data signal with a bit structure suitable for processing by a general processing device such as a microcomputer, organized in a predetermined order, and then sent to the recording device 8 through an interface attached to the data processing circuit 16. write to. Note that the recording device 8 includes, for example, a cassette magnetic tape (CMT).
It is preferable to use something that is relatively easy to take out and replace, such as IC memory, paper tape, magnetic card, magnetic disk, etc.

After completing a series of measurement operations, each data measured and recorded as described above is read out by a computer or the like, processed, and used as distribution information of the air dose rate.

As is clear from the above description, according to the radiation measuring device of the present invention, a measurement position signal is given to the signal detection element corresponding to the measurement position using a measurement position indicating pen while looking at a floor map that is a reduced drawing of the work space. By doing this, measurement position data can be obtained easily and quickly at the same time as the measurement of the air dose rate, and can be recorded in the recording device inside the measurement position body together with the air dose rate measurement data and measurement time data. It has a similar effect.

(1) There is no need to read the data one by one from the meter and judge the measurement position from the floor plan and write it on the recording paper as in the past, making the work easier and significantly reducing the measurement time. .

(2) Errors in reading and writing measurement data are eliminated, and the determination of measurement positions is standardized and performed simply, quickly, and accurately, improving the reliability of the data.

(3) Since the measurement time is also recorded at the same time, it is possible to correct the measurement data and judge the reliability according to changes in the conditions of the work space, making it possible to accurately evaluate the air dose rate distribution.

(4) Data processing is facilitated because it can be organized and recorded in a signal format suitable for arithmetic processing by a computer or the like.

(5) By shortening the time required for measurement work, the amount of radiation exposure of the person being measured can be reduced, improving safety.

It should be noted that the present invention is not limited to the above-mentioned embodiments; for example, a position detection method using electrical resistance and capacitance coupling in addition to an optical method may be applied; The number of signal detection elements in the dimensional array can be sequentially selected depending on the degree of measurement position detection resolution.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a radiation measuring device showing an embodiment of the present invention, and FIG. 2 is a block diagram showing the circuit configuration of the measuring device of FIG. 1... Measuring device main body, 2... Radiation detector, 5
...Measurement position detection coordinate section, 6...Floor map,
7... Measurement position indicating pen, 8... Recording device, 10
... Measurement trigger switch, 11 ... Radiation signal processing circuit, 12 ... Measurement time circuit, 13 ... Instruction signal input circuit, 14 ... Signal detection element, 15a, 1
5b...Measurement position decoding circuit, 16...Data processing circuit.

Claims (1)

[Claims] 1. A radiation measuring device for measuring radioactivity distribution in a work space, which includes a radiation detector and a radiation signal processing circuit for measuring the air dose rate at any measurement point, and a radiation signal processing circuit for measuring the time of measurement. a measurement time circuit, a measurement position detection coordinate section consisting of a group of signal detection elements arranged in a two-dimensional matrix, a floor map that is placed in close contact with the measurement position detection coordinate section and depicts the work space; A measurement position indicating pen that applies a signal to the signal detection element from the floor map, an instruction signal input circuit that inputs a signal to the measurement position indication pen, and an address of the signal detection element that receives the signal in the measurement position detection coordinate section. a measurement position decoding circuit that decodes the measurement position;
a data processing circuit that processes signals respectively input from the radiation signal processing circuit, the measurement time circuit, and the measurement position decoding circuit; a recording device that records data from the data processing circuit; and a trigger switch circuit that determines measurement timing. A radiation measuring device comprising: 2. The radiation measuring device according to claim 1, wherein the radiation signal processing circuit and the measurement time circuit are each connected to a display section that digitally displays the air dose rate and the measurement time.