RU2025745C1 - Household dosimeter - Google Patents

Abstract

FIELD: ionizing radiation metering. SUBSTANCE: household dosimeter has a detector, an aligning and blocking unit, decoder counter, display unit, reference generator, self-exciting generator, multiplier, sound alarm unit, reset unit, filter unit, switches, power supply, connection diagram, logic unit, overflow and power pack discharge unit, feedback unit. EFFECT: wider operating opportunities. dwg 1

Description

 The invention relates to the measurement of ionizing radiation and relates, in particular, to devices for individual dosimetric control.

 A known ionizing radiation dosimeter comprising a replaceable radiation detector, two keys, a stable current source, two switches, an analog-to-digital converter, a computing unit, a reading unit for initial parameters and an indicator. The dosimeter takes into account voltage drops at the points of contact with the terminals of the removable radiation detector, determines the voltage drop across the detector and adjusts the radiation dose value.

 The disadvantage of this dosimeter is also limited functionality.

 The closest technical solution (prototype) to the invention is an external gamma radiation indicator "Bella", comprising a detector, a decoder counter, an information display unit, a driving generator, a voltage converter, an audible alarm unit, a reset unit, a power filter unit, a switch, a battery, block matching and blocking.

 The aim of the invention is the expansion of functionality.

 The goal is achieved in that in a household dosimeter containing a detector, counter, decoder, information display unit, master oscillator, multiplication unit, audible alarm unit, reset unit, power filter unit, switch, power supply, self-excited generator, matching and blocking unit , a wiring diagram, a logic block, an overflow and discharge block of a power source, a feedback block are introduced. The matching and blocking unit additionally allows you to amplify the signal in accordance with the electrical parameters of the decoder counter circuit; the master oscillator additionally provides the frequencies necessary for the circuit to operate in gamma and beta measurements; the self-excited generator additionally provides high voltage stabilization by discharging the capacitors of the multiplier unit under the load of the detector and the resistors of the feedback divider divider: the detector output is connected in series with the first input of the information display unit through the first inputs of the matching and blocking unit of the decoder counter, the second output of the decoder counter is connected to the first the input of the overflow unit and the discharge of the battery, the control signal from the output of which is connected to the third input of the unit sound howl signal and the second - to the second input unit displaying information; the mode switch is connected to the first input of the master oscillator, and the range switch is connected to the fourth input of the logic block, while the output of the master oscillator is connected to the third input of the logic block, the first output of which is connected to the third input of the matching and blocking unit, the second to the first input of the sound block alarm, and the third to the first input of the reset unit, the output of which is connected to the first input of the logic unit and the third input of the decoder counter; the first output of the communication processing unit is connected to the first input of the generator with self-excitation, and the second input is connected to the third input of the overflow and battery discharge unit, the output of the generator with self-excitation is connected to the multiplier unit, the output of which is connected to the detector input and the first input of the feedback unit; From the power source, through the switch and the power filter unit, the voltage is connected to the second inputs of the reset, feedback, matching, and blocking units, logic, audible alarm, overflow and discharge of the power source, self-excited generator, master oscillator, decoder counter.

 The drawing shows a structural diagram of the proposed dosimeter.

 The household dosimeter comprises a detector 1, a matching and blocking unit 2, a counter 3, an information display unit 4, a driving generator 5, a mode switch 12, a range switch 13, a feedback block 17, a self-excitation generator 6, a multiplier 7, an audible alarm unit 8, a reset unit 9, a filter unit 10, a power switch 11 (on), a power source 14, a divider 15, an overflow and discharge unit 16 of the power source.

 The dosimeter works as follows.

 The pulses from the detector 1 are fed to the matching and blocking unit 2, where they are amplified and matched with the electrical parameters of the counter 3. The pulses in the counter 3 are accumulated and converted into a logical signal, which is indicated in the information display unit 4, and the counter overflow signal from the second output of the counter 3 arrives at the first input of block 16 overflow and discharge of the power source. The duration of the measurement is determined by the master oscillator 5 and the divider 15. The master oscillator 5 has two timing circuits that determine the gamma or beta mode of measurement depending on the position of the switch 12. The measuring range "x1" and "x10" is determined by the position of the switch 13. Fixation of measurement readings carried out by block 2 coordination and blocking. From the output of the divider 15 through the reset unit 9, the circuit is reset. The sound signal is generated by the sound alarm unit 8 when the measurement is completed and the signal from the divider 15 is received, as well as when the signal comes from the overflow unit 16 and the discharge of the power source, which generates a control signal at the first output when the counter 3 overflows and the discharge of the power source 14. The detector 1 is powered by a high DC voltage of 400 V, which is generated and stabilized by the feedback unit 17, a generator 6 with self-excitation, a multiplier 7. A generator 6 with self-excitation generates the pulses necessary for the operation of the multiplier 7, and modulates the pulse repetition rate depending on the control signals arriving at the first input of block 6.

 When lowering the high voltage of the detector 1, the cause of which is the discharge of the power supply 14, the generation of control pulses from the second output of the feedback block 17 to the third input of the overflow and discharge of the power supply 14 is stopped.

 The voltage in the circuit of the device is supplied 9 V from the power element 14 by turning on the switch 11, while the suppression of interference on the power circuit is carried out by the filter unit 10.

 The purpose and specific implementation of the device blocks.

 Block 2 matching and blocking amplifies and normalizes the output signal from the detector 1 and blocks the passage of its output signals to the counter 3 at the time of indication of the dosimeter without changing them.

 The counter 3 counts the number of pulses from the detector 1 through the block 2 matching and blocking and converts them into a signal for display in block 4 information display. The information display unit 4 displays information of the counter 3 and the overflow and discharge unit 16 of the power source.

 The master oscillator 5 generates a pulse repetition rate for the Gamma and Beta modes.

 The divider 15 performs the division of the frequency of the master oscillator and forms a time interval for the measurement of "x1" and "x10"; creates a time interval in the indication of the dosimeter; controls block 2 matching and blocking, block 8 sound insulation and block 9 reset.

The feedback unit 17 stabilizes the high voltage at the detector 1 by applying a control signal to the generator 6 with self-excitation. During normal operation of the generator 6 with self-excitation and the multiplier 7, the detector voltage 1 to 400 V is supplied to the input of the feedback loop detector 1, which has a small ripple due to the discharge of the multiplication capacitors 7 under the load of the detector 1 and the resistors of the divider of the feedback block 17. The divider 15 is selected so that at the gate of the transistor the ripple of the potential passes through the thermostable _cutoff point U, and the load of the transistor in the drain circuit is a high-impedance resistance, so the transistor goes from a closed state when U _close >> U _cut , to saturation when U _close > U _cut , those. works in transistor switch mode.

 The amplifier of the pulsating drain signal of the transistor is a transistor at the generator input with self-excitation, which amplifies the weak currents of the transistor cascade of the feedback block 17 and eliminates the influence of the load RC circuit on the cascade of this transistor.

 When the high voltage of the detector 1 is lower than 400 V, the transistor of the feedback unit 17 opens, due to the lowered power, the generator 6 is not able to self-excite itself to increase the voltage of the detector 1 to> 400 V. The ripple of the transistor of the block 17 stops, the transistor amplifier key goes into closed state. The voltage on the capacitor of the RC circuit of the overflow and discharge unit of the power source 16 increases to the voltage of the power source, which is a control signal for displaying the indication of the discharge of the power source on the unit 16.

 The generator 6 with self-excitation generates a pulse to power the multiplier 7, changing their duty cycle depending on the control signal of the feedback block 17.

 The sound alarm unit 8 generates a short-term sound signal at the end of the measurement cycle when a control signal is received from the divider 15. It gives a continuous sound signal when a control signal is received from the overflow and discharge unit 16 of the power source.

 The overflow and discharge unit 16 of the power source supplies a control signal from the first output to the third input of the audible alarm unit 8 when the counter 3 is overloaded and the power source 14 is discharged, and also generates a control signal to the second input of the information display unit 4 to indicate the light signal of the points on unit 4 when discharging the power source 14.

 The reset unit returns the circuit to its original position at the end of the measurement cycle, restores the counter 3 and the divider 15.

 Block 10 filters suppresses interference of high and low frequencies in the power circuit.

 A household dosimeter allows the population to measure the radioactive contamination of food, water, clothing, and the environment. The measurement is carried out in a wide range of ionizing radiation energy from 100 keV to 1.2 meV for beta and gamma radiation, moreover, such isotopes as Cs137, Sr90. The circuit design and design of the dosimeter provide information on the radiation state of the environment within 4 s.

Claims (1)

 A HOUSEHOLD DOSIMETER, comprising a detector, a matching and blocking unit, a counter, an information display unit, a master oscillator, a self-excited generator, a multiplier, an audible alarm unit, a reset unit, a filter unit, a power switch, a mode switch and a power source, characterized in that, in order to expand the functionality, a divider, an overflow and discharge unit of the battery, a communication processing unit, a detector output are connected to the first input of the matching and blocking unit, an output, a sec. the first and third inputs of which are respectively connected to the first input of the counter, to the first output of the divider and to the first output of the power switch connected to the second output and input, respectively, with the filter unit and the output of the power source, the first and second outputs of the counter are connected respectively to the first inputs of the information display unit and the overflow and discharge unit of the battery, the first and second outputs, as well as the second and third inputs of which are connected respectively to the first input of the sound alarm unit, the second at the input of the information display unit, the first output of the power switch and the first output of the feedback unit, the second output of which is connected to the first input of the generator with self-excitation connected to the output of the multiplier, the output of which is connected to the input of the detector and the first input of the feedback unit, the second input of which connected to the output of the power switch by the first inputs of the divider, the master oscillator and the reset unit and the second inputs of the generator with self-excitation, a counter and an audible alarm unit, associated third by an input with a second output of the divider, the third output, as well as the second third and fourth input of which are respectively connected to the second input of the reset unit, to its output, the output of the range switch and the output of the master oscillator, the second input of which is connected to the output of the mode switch, while the output the reset unit is connected to the third input of the counter.

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