JPS61155787A - Automatic radiation measuring apparatus - Google Patents

Abstract

PURPOSE:To perform a complicated radiation measuring work automatically in a handy manner, by memorizing radiation measuring procedures into a compact memory means to operate measuring equipments according to the procedures. CONSTITUTION:Prior to measurement, necessary measuring procedures should be memorized into a sequence memory means 25. First, by a position moving routine, an automatic radiation measuring apparatus moves to the measuring point. Then, measuring conditions or the like memorized into the sequence memory means 25 are read out with a sequence controller 22, measuring equipments are set on the conditions. Then, measurement is started to operate a printer 19 and a data memory 21 by computation. With such an arrangement, according to the procedures memorized into the sequence memory means, a wide variety of radiation measuring works are done almost automatically at many measuring points. Automatic return is also possible by a necessary data obtained, contributing to the labor saving for the management of a radiation facility.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an automatic radiation measurement device used for radiation measurement.

"Conventional Technology" At facilities that use radioactive materials, such as nuclear power plants, radiation measurements are carried out in controlled areas and surrounding areas to ensure the safety of workers and prevent environmental pollution.

For this purpose, for example, a scintillation counter as shown in FIG. 8 and various devices for processing the output thereof are used.

FIG. 8 shows a block diagram of the main parts of the scintillation counter.

In the figure, for example, thallium activated sodium iodide N
When radiation 2 is incident on scintillator 1 made of a1 (TI), scintillator 1 emits light according to the energy of the radiation. When this light is amplified by the photomultiplier 3 and sent to the amplifier 4, the amplifier 4 outputs an electric pulse with a voltage proportional to the energy of the incident radiation.

These electrical pulses are output one after another each time radiation is randomly input to the scintillator 1, but in order to select the radiation with the energy level that you want to measure from among the incident radiation, the discriminator 5 use.

The discriminator 5 sorts the electrical pulses output from the amplifier 4 by a predetermined level of voltage (referred to as a threshold) and counts only those that exceed this threshold. The data obtained in this way is computed by the arithmetic processing device 6. Here, further, by using two discriminators with different threshold values, use the discriminator with the smaller threshold value (from the given value, use the discriminator with the higher threshold value to obtain By subtracting the calculated count value, it is also possible to count the amount of incident radiation at a level between the two threshold values.

A combination of two discriminators in this manner is called a single channel analyzer. The smaller threshold is called a baseline voltage, and the difference between the higher and lower thresholds is called a window voltage.

Alternatively, the radiation energy distribution may be measured by keeping the window width of a single channel analyzer constant and moving the baseline voltage little by little.

Further, such a single channel analyzer uses a scaler that counts electrical pulses. Generally, pulses caused by radiation have irregular pulse intervals even if the ratio of pulses input to the scaler per unit time is irregular, so the scaler is required to have high resolution. Since the sequencer counts the number of pulses input within a certain period of time, it is necessary to set conditions such as time setting, start, and stop.

Furthermore, in single channel analyzers, when tracking the temporal phenomenon of electrical pulses, in order to accurately determine when the pulse is input, the timing when the highest value of the electrical pulse is input is detected as the time when the electric pulse is input manually. It is necessary to select a peak sensing method that detects the peak value, a constant fraction method that detects when the value has decreased by a certain percentage from the maximum value, a zero crossover method that detects the zero crossing point of the bipolar pulse, etc. Such timing characteristics must also be appropriately selected depending on the nature of the energy of the radiation to be measured, the purpose of the measurement, etc.

Furthermore, the amplifier that amplifies such pulses also has a degree of amplification and an output method that must be selected depending on the purpose of measurement. For example, as the output of the amplifier, there are two methods: one is to output unipolar pulses with a good SZN ratio, and the other is to output bipolar pulses suitable for high counting rates.

As described above, when measuring the energy of radiation, the operation of various devices and the setting and selection of conditions are extremely complicated. Moreover, it is not uncommon to repeatedly perform various types of measurement tasks using the same equipment.

There is an edict that if such measurement work lasts a long time, the radiation exposure of the person taking the measurements will increase.

Therefore, conventional attempts have been made to input a program for performing complex measurement work into a computer, connect this computer to a measuring device, and have the computer perform the measurement work automatically at high speed and accurately. . The data obtained from the measurements are calculated and analyzed by this computer, and various outputs are obtained.

``Problems to be solved by the invention'' In this way, efforts have been made to automate and speed up the work of measuring and analyzing radiation energy, but large computers are used for this work, and the space occupancy rate has increased. The drawback was that it was expensive.

In addition, the measurer must become familiar with the handling of such combinations. Moreover, when the measurement points are widely dispersed, it is necessary to transport and move such a relatively large-scale device using a car or the like, or to install as many devices as there are measurement points. .

The present invention has been made to solve the above problems, and an object of the present invention is to provide an automatic radiation measurement device that can automatically perform complicated radiation measurement operations with relative ease.

"Means for Solving the Problems" The automatic radiation measuring device of the present invention includes a measuring means composed of a plurality of measuring devices that perform radiation measurements and process the measurement data, and a measuring operation procedure of this measuring means. It is characterized by comprising a stored sequence storage means, and a sequence controller that reads the measurement procedure stored in the sequence storage means and operates the equipment of the measurement means according to the procedure.

Note that this measuring means is preferably provided with a position moving device that moves the position according to movement position information stored in the sequence storage means.

Further, the sequence controller may include a microcomputer, and the sequence storage means may include a storage element detachably attached to the sequence controller.

Furthermore, the sequence controller has an operation panel,
The measurement procedure input from this operation panel may be stored in the sequence storage means, and the equipment of the measurement means may be operated according to this procedure.

In this way, the automatic radiation measurement device of the present invention stores the radiation measurement procedure in a compact storage means and operates each measurement device according to the procedure, so it does not use a large-scale computer or the like. If necessary, a learning function can be added to input a new measurement procedure from the operation panel or the like.

Furthermore, if it is made possible to move automatically and perform measurements, it is possible to fully automate the measurement work.

``Example'' [Overall view] FIG. 1 is a perspective view showing the appearance of an automatic radiation measuring device of the present invention.

This automatic radiation measuring device is mounted on a rack with a cart 11 attached. On the left side of the front side, there is an operation panel 12 used for inputting measurement procedures, etc., and a control panel 13 equipped with a power switch etc., and a detector 14 such as a scintillation counter is housed in a box on the right side. Furthermore, various measuring instruments are housed inside the lower door 15.

[Block description]

A block diagram of the entire automatic radiation measuring device is shown in FIG. 2.

This automatic radiation measuring device includes a detector 14, an amplifier 1
6, single channel analyzer 17, scaler 18,
It is composed of a printer 19, a data memory 21, a sequence controller 22, a power damper 23, an operation panel 24, a sequence storage means 25, a position moving device 26, and the like.

These devices are connected to one common path line 31 as shown in the figure.
are connected to each other via necessary interfaces (not shown). For this common path line 31, for example, one of the R3-232C system, which is a common standard for computer equipment, or the IEEE488-1975 line, which is the AEC-NIM standard established by the American Atomic Energy Commission, etc., is used. In the latter case, the bottle power supply and connector are already wired inside the aluminum case as a NIM module, which is ideal for implementing the present invention.

As the detector 14, two or more types may be prepared, including not only a scintillation type detector but also a Ge'PSi type detector if necessary, and each of them may be connected to the common path line 31.

The amplifier is for amplifying the electric pulse output from the detector 14, and is composed of, for example, a preamplifier, a spectroscopic amplifier, or the like.

Single channel analyzer 17 and scaler 18 are of known construction as previously described.

The printer 19 is for outputting the results obtained by measurement in the form of a numerical table or graph, and is a dot printer, a character printer, or the like.

The data memory 21 is used to temporarily store measurement results when they are analyzed by a large computer or the like.
Uses memory (RAM), magnetic disk, etc.

The power damper 23 supplies the necessary power to each measurement device, and the sequence controller 22
It is equipped with a switch that shuts off the power supply according to instructions from the operator.

The measuring means 40 is constituted by the above-mentioned equipment.

The sequence controller 22 is composed of a microprocessor, its peripheral circuits, etc., and reads out the procedures stored in the sequence storage means 25, changes the measurement condition settings of each measuring device, and controls the rearrangement of the connections of each measuring device. It is something.

The sequence storage means 25 is composed of a random access memory (RAM), a read-only memory, etc., and may be one in which procedures for radiation measurement work are written and stored in advance using another large-sized computer or the like, or the sequence storage device 25 shown in FIG. It consists of a storage means that inputs procedures from the operation panel 12 using the device and stores them. The operation panel 12 is the first
1! As shown in FIG. 1, the display 12. and a keyboard 122, press the select key 1221 to switch the menu, press the cursor key 1222 to move the cursor to the required location, input each predetermined condition etc. using the number keys 1223, and press the set key 1224. By pressing , for example in this figure, the start time of the measurement operation of the scaler 17 is set.

[Measurement conditions, etc.]

In this way, in order to use the measuring means 40, the measurement conditions are set, and examples of the menu of the measurement conditions include the following.

(1) Main amplifier gain, input polarity, bipolar, unipolar (ii)
Single channel analyzer baseline voltage, window voltage, peak sensing, constant fraction, zero crossover, mode selection for use as a discriminator (iii) Scaler preset time, start, stop, clear (iv) Printer print presence/absence (iv) V) Data memory Whether or not data is stored (vi) Whether or not there is automatic voltage cutoff after power damper measurement work is completed.In addition to these measurement conditions, information regarding measurement procedures such as the number of measurements and rearrangement of connections of measurement equipment. is also required.

Examples of this are shown in FIGS. 3(1) and 3(2). (1) in this figure shows the connection state when writing the output of the multichannel analyzer (MCA) to a printer, and (2)
) shows the connection state for counting the output of a single channel analyzer (SCA) with a scaler and storing it in the data memory. As shown in the flowchart in Figure 4, this series of information is input by human interaction using the operation panel, then decoding, organizing, and printing out the input data, and then converting it into machine language. , and then stored in the sequence storage means.

The sequence controller 22 in FIG. 2 sequentially reads and executes the contents stored in the sequence storage means 25 as shown in FIG. 4.

[Move position]

Further, in the automatic radiation measuring device of this embodiment, a position moving device is provided on the cart 11 shown in FIG. 1, and it can be moved back and forth and left and right by a motor using a battery or the like.

Although not shown, it can also be expanded and contracted up and down using a hydraulic jack or the like.

FIG. 5 is a block diagram thereof, and FIG. 6 is a flowchart of its operation.

The sequence controller 22 includes a movement amount sensor 41 that measures the amount of movement when this cart moves back and forth and left and right.
is attached, and the sequence controller 22 controls the drive motor 42 based on this output. It also controls a turning device 43 that changes the direction of movement. This movement is executed after the sequence controller 22 reads movement position information from the sequence storage means 25.

Next, the flowchart of FIG. 6 will be explained.

First, when moving, set the direction of movement (step ■), turn on the drive motor (step ■), repeat changes in direction while monitoring the amount of movement (steps ■, ■),
When the movement is completed, stop the motor (step ■).

In this way, the automatic radiation measuring device can be moved to the measurement location unattended.

In this way, the sequence storage means of the automatic radiation measurement device of the present invention includes measurement positions, selection and connection of measurement equipment,
All information such as measurement conditions and number of measurements is written.

[Measurement operation]

FIG. 7 is a flowchart showing the operation of the automatic radiation measuring device of the present invention having the above-mentioned functions.

It is assumed that the necessary measurement procedures are stored in the sequence storage means prior to measurement.

First, the automatic radiation measuring device moves to the measurement point according to the position movement routine explained with reference to FIG. 6 (step 2). Next, the measurement conditions etc. stored in the sequence storage means are read out by the sequence controller, and each measuring device is set to the conditions (step 1).
). Then, measurement is started (step ■), calculations are performed (step ■), and the printer and data memory are operated (step ■).

A judgment loop (■) monitors whether this measurement operation has been performed the necessary number of times, and a judgment loop (■) monitors whether it is necessary to perform measurement under another condition (decision loop ■), and repeats this series of operations as many times as necessary.

Finally, when turning off the power, activate the power damper (
Judgment ■ and Step ■).

When the automatic radiation measurement device is operated as described above, a wide variety of radiation measurement operations are almost automatically performed at a large number of measurement points in accordance with the procedures stored in the sequence storage means.

The automatic radiation measuring device of the present invention is not limited to the above embodiments. If the measurement points are concentrated in a relatively narrow area, move the cart carrying only the detector or the equipment connected to it, and place other equipment and sequence controllers on a fixed stand. Alternatively, the two may be connected by a flexible cabtire cable or the like.

In addition, if the sequence storage means is a ROM element or a RAM element backed up by a battery attached to the board and connected to the sequence controller using a detachable connector, different measurement tasks can be performed by replacing the board. It can be carried out.

Furthermore, this automatic radiation measuring device may be equipped with a changeover switch, etc., which is used not only for automatic measurement work, but also for manual measurement by a measuring person. When performing manual measurement work, if the procedure is automatically written into the sequence storage means, automatic measurements can be performed using the same procedure from the next time onwards.

"Effects of the Invention" The automatic radiation measurement device of the present invention described above can automatically perform radiation measurement work with complicated procedures at high speed and with high precision, so that the measurement work can be automated, and It is also possible to reduce the labor of the measurer and reduce his or her exposure to radiation. Furthermore, the operation does not require any work such as creating a computer program. Moreover, it can be manufactured relatively inexpensively.

It is also possible to move sequentially through controlled areas under high radiation levels, perform measurement work, and automatically return after obtaining the necessary data, which is extremely useful for labor-saving management of radiation facilities. It is something. .

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the external appearance of an embodiment of the automatic radiation measuring device of the present invention, Fig. 2 is a block diagram thereof, Fig. 3 is a block diagram showing an example of connection of measuring equipment, and Fig. 4 is a diagram showing the measurement procedure. 5 is a block diagram showing an embodiment of the position moving device, FIG. 6 is a flowchart of its operation, and FIG. 7 is a flowchart of measurement operation of the automatic radiation measurement device of the present invention,
FIG. 8 is a block diagram showing an example of a conventional radiation measuring device. 12... Operation panel, 22... Sequence controller, 25...
... Sequence storage means, 26 ... Position moving device, 40 ... Measurement means. Applicant: Representative of Japan Atomic Energy Corporation
Person Patent Attorney Umeo Yamauchi Figure 1 Figure 6

Claims (1)

[Scope of Claims] 1. A measuring means composed of a plurality of measuring devices that performs radiation measurements and processes the measurement data, a sequence storage means that stores measurement operation procedures of this measuring means, and this sequence storage An automatic radiation measurement device comprising: a sequence controller that reads a measurement procedure stored in the measurement device and operates the equipment of the measurement device according to the procedure. 2. The automatic radiation measuring device according to claim 1, wherein the measuring means is provided with a position moving device that moves the position according to movement position information stored in the sequence storage means. . 3. The automatic radiation therapy system according to claim 1 or 2, wherein the sequence controller has a microcomputer, and the sequence storage means comprises a storage element detachably attached to the sequence controller. The measuring device 4 and the sequence controller store a measurement procedure input from an operation panel provided in the measuring means in a sequence storage means, and operate the equipment of the measuring means according to this procedure. The automatic radiation measuring device according to items 1 to 3.