JPS6045379B2 - Radiation dose measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of Application of the Invention The present invention relates to an apparatus for automatically measuring the amount of radiation exposure and remotely transmitting the measured values, and in particular to an apparatus for automatically measuring the amount of radiation exposure of individuals and transmitting the measured values remotely. Concerning transmission and remote display and recording equipment.

(2) Prior art Personal radiation exposure measuring devices conventionally used in radiation handling facilities such as nuclear power plants include devices that combine an ionization chamber pocket dosimeter and a charging device, and TLD (thermal fluorescence dosimeters). ) and a radiation exposure reading device are common.

The former device uses a fixed radiation dose (for example, 500 mrem)
Although it is possible to continuously measure the integrated value up to a maximum of 100%, it is not suitable for remote transmission and automatic measurement of measured quantities because it requires human intervention during charging and reading the exposure amount. The latter method is not suitable for automation because it requires inserting a detector into the exposure reading device to read the measured values. Furthermore, once read, the value is reset and only the integrated value up to the reading can be measured. In addition, radiation work 1
Regarding persons, etc., not only the cumulative amount of radiation exposure but also
Radiation exposure during one work must be managed so that it is within a certain standard value. Conventionally, the integrated value of the radiation exposure amount is accumulated on a daily basis by having the worker wear the above-mentioned pocket dosimeter or TLD and write the reading on a card each time the worker completes the work. This method may lead to errors in reading and recording radiation exposure amounts. In addition, regarding the amount of radiation exposure during one task, for example, workers wear an alarm meter (a device that emits a buzzer when a standard value is set and the amount of radiation exposure reaches the set value), and when the buzzer goes off, they work voluntarily. We are managing the radiation facility by canceling the radiation therapy and ensuring that the patient leaves the radiation facility. In this method, the radiation manager sets the reference value, but the worker himself makes the decision as to whether or not to stop the work, so there is a possibility that he will be exposed to radiation that exceeds the reference value.
(3) Purpose of the Invention The present invention improves the above-mentioned drawbacks, and is capable of not only automatically measuring the individual radiation exposure doses of multiple people at the same time without having to obtain them, but also remotely transmitting the moment-by-moment radiation exposure doses. The purpose of the present invention is to provide a radiation dose measuring device that can record and display measured values remotely, thereby preventing errors in recording measured values and preventing workers from being exposed to radiation exceeding the standard value.

(4) Examples Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 1 shows an embodiment of a device based on the present invention.

In the figure, 1 is a radiation measuring device, and 2 is a radiation management device. The radiation measuring device 1 includes a GM tube type radiation detector 3, a card reader 4, voltage-frequency converters 5 and 6, a mixer 7, a frequency modulation wireless transmitter 8, and an antenna 9. . Each component of the radiation measuring instrument 1 is a combination of conventional devices. The GM tube type radiation detector 3 obtains a voltage output proportional to the amount of incident radiation. The card reader 4 is a personal identification device for identifying workers working in radiation handling facilities, that is, individuals exposed to radiation, and is owned by each individual. This is to decipher the code that can identify an individual recorded on the card. For example, this card reader 4 reads the bit configuration of a perforated card with an 8-bit configuration, and is composed of a light source, a light receiving element, an amplifier, etc., and has a structure to obtain a single voltage output corresponding to the bit configuration. be. The voltage-to-frequency converters 5 and 6 convert analog signals from the radiation detector 3 or card reader 4 into digital signals, and when a voltage signal is input, they output a pulse signal with a frequency proportional to the input voltage. be. The mixer 7 mixes the two systems of pulse signals from the two voltage-to-frequency converters 5 and 6, and
It obtains the output signal of the system, and consists of, for example, an amplifier.
The wireless transmitter 8 transmits the signal from the mixer wirelessly and remotely. For example, the carrier wave from a crystal oscillator is frequency-modulated with the input signal from the mixer 7, and then the power is amplified and the radio wave is transmitted from the antenna 9. Output as . The wireless transmitter consists of a crystal oscillator, a semiconductor element, a coil, a capacitor, a resistor, and the like. The radiation control device 2 includes a receiver 10 (adopts a superheterodyne method) that receives and demodulates frequency modulated radio waves, a variable frequency oscillator 11 whose oscillation frequency can be selected by an external signal, an antenna 12, and an Oki wave generator. 13,
14, frequency-to-voltage converters 15, 16, process input/output device 17, electronic calculator 18, CRT 19, typewriter 20, and cassette type magnetic tape recording device.

Each component of the radiation management device 2 is a combination of conventional devices. The receiver 10 receives and demodulates frequency modulated radio waves, and is comprised of a semiconductor element coil, a capacitor, a resistor, and the like. The variable frequency oscillator 11 is a combination of a plurality of crystal oscillators and a PLL (phase lock loop) element, and outputs an arbitrary high frequency by applying an external signal. Fuchinoki 13
, 14 is the Imperial Okinawa equipment, which consists of amplifiers, etc. The frequency-to-voltage converters 15 and 16 obtain a voltage output proportional to the frequency of the input pulse. The process input/output device 17 has two analog input systems, and obtains an output that matches the input signal to the input of the electronic computer 18 . Electronic computer 18, CRT19,
Since the typewriter 20 and the cassette type magnetic tape recording device are commonly used, a description thereof will be omitted. The operation of the apparatus of the present invention will be explained below.

Workers who work in radiation handling facilities have a card to identify themselves, and when working in a radiation handling facility, insert the card into the card reader 4 of the radiation measuring instrument 1, The worker carries the radiation measuring device 1 with him and enters the work site.

When a card is inserted into the card reader 4, for example, if it is a perforated card, a voltage signal corresponding to the bit arrangement of the perforated card is output. This voltage signal is converted via a voltage-to-frequency converter 6 into a pulse signal having a period corresponding to the voltage signal. Further, the GM tube type radiation detector 3 outputs a voltage signal proportional to the amount of incident radiation. This voltage signal is converted via the voltage-frequency converter 5 into a pulse signal having a period corresponding to the voltage signal. Here, in order to distinguish between the pulse period corresponding to the signal from the card reader 4 and the pulse period corresponding to the signal from the GM radiation detector 3, the pulse period corresponding to the signal from the card reader 4 is set to, for example, 100 Hz. Up to 3KHz, and the pulse period corresponding to the signal of the GM radiation detector 3 is, for example, 5K ratio ~
Up to 1 (branch) Hz. The signals from the voltage-to-frequency converters 5 and 6 are mixed by a mixer 7 and then input to a wireless transmitter 8. The wireless transmitter 8 uses a carrier wave (for example, 150r11/
1Hz band) with the signal from the mixer 7 and transmit it from the antenna 9. Here, when multiple workers use multiple radiation measuring instruments 1 at the same time, the radiation measuring instruments 1
The frequency of the carrier waves of the punched card is individually set and identified by the frequency, and the user sets the bit configuration of the punched card individually and identifies it by the voltage signal corresponding to the bit configuration.
When a worker wears the radiation measuring device 1 and works as described above, the amount of radiation exposure for each worker can be automatically measured and the value can be transmitted remotely. Next, the signal from the radiation measuring device 1 is transmitted to the antenna 12 of the radiation management device 2.
demodulated by the receiver 10 via the 100Hz-3KH
z and 5KHz-10KHz pulse signals are obtained. Since the receiver 10 employs a superheterodyne system, only the target carrier wave can be selectively received by selecting the frequency of the variable frequency oscillator 11, which is a local oscillator. Therefore, a plurality of radiation measuring instruments 1 can be identified. The pulse signal from the receiver 10 is a band transducer; it becomes a pulse signal of 100 Hz to 3 KHz via the transducer 13, and becomes a pulse signal of 5 KHz to 10 KHz via the transducer 14. The output signal of the Okiwave device 13 is converted into a voltage signal via a frequency-to-voltage converter 15. This voltage signal corresponds to the output signal of the card reader 4 of the radiation measuring instrument 1. The output signal of the filter 14 is converted into a voltage signal via a frequency-voltage converter 16. This voltage signal corresponds to the output signal of the GM tube type radiation detector 3 of the radiation measuring instrument 1. Frequency-to-voltage converter 15, 16
The output signal is taken into the electronic computer 18 via the process input/output device 17, where it is converted into a radiation dose, the radiation dose is integrated, and the radiation measuring device 1 and the user of the radiation measuring device 1 are identified. These data can be sent to CR as necessary.
It is displayed on the screen of Tl9, printed by typewriter 20, and recorded on a cassette type magnetic tape recording device. (6) Summary As explained above, according to the present invention, it is possible to automatically measure the radiation exposure amount of multiple individuals at the same time without human intervention, and it is also possible to remotely transmit the radiation exposure amount from moment to moment. We can provide a radiation dose measurement device that can record, print, and display information.

Therefore, radiation managers can remotely monitor the radiation exposure of workers, eliminating unnecessary radiation exposure, and preventing errors in recording measurement values and preventing radiation exposure from third-party radiation managers. Since the amount of radiation exposure of workers can be directly controlled, it is possible to prevent workers from receiving radiation exposure that exceeds the standard value. In addition, conventionally, workers had to carry pocket dosimeters and alarm meters while working, but by using the device of the present invention, workers can manage radiation exposure in the conventional manner by simply carrying only a radiation measuring device. .

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of a radiation dose measuring device based on the present invention.

Claims (1)

[Claims] 1. A radiation detector using a GM tube or an ionization chamber, an analog-to-digital converter that converts an analog signal from the radiation detector into a digital signal, and an individual who identifies an individual exposed to radiation. an identifying device, an analog-digital converter that converts the analog signal from the personal identifying device into a digital signal, and a mixing device that mixes two systems of signals from the two analog-digital converters and outputs one system of signals. a radiation measuring device comprising a radio transmitter that remotely transmits a signal from the mixer by radio; a receiver that receives and demodulates a carrier wave from the radio transmitter; and a receiver that discriminates the signal from the receiver. a digital-to-analog converter that converts a digital signal from the filter into an analog signal; an electronic computer equipped with a process input/output device that organizes or edits data from the converter; 1. A radiation dose measuring device comprising: a device for displaying, printing, or recording data from the device; and a radiation control device equipped with a device for displaying, printing, or recording data from the device. 2. The radiation dose measuring device according to claim 1, wherein the personal identifier is a card reader that reads a code that can identify an individual recorded on a card owned by each individual.