JPS6042676A - Radiation dosimeter - Google Patents

Abstract

PURPOSE:To prevent stored data from being disappeared and to improve the function and reliability of a dosimeter by generating a warning when a source voltage drops below a specific value, and stopping the supply of electric power to the dosimeter except a memory. CONSTITUTION:When the source voltage drops below the specific value, a battery consumption detecting circuit 2 detects that and generates an output S, and a microcomputer 1 sends a signal to put an alarm 3 in operation, generating a warning. Then, the microcomputer 1 is placed in a stand-by state and a signal S' is generated to operate switches 4 and 7 for driving a preamplifier 5 and a high-voltage power source 6 for a detector, thereby the power supply in turned off. The power from the battery is consumed only by the memories 13 and 14 thereafter and the power consumption is reduced extremely.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention measures radiation intensity or radiation dose (generally represents the integrated radiation dose, and the unit is R (roentgen) or mR (milliroentgen)). , relates to a portable radiation dosimeter (hereinafter also simply referred to as a dosimeter) that is designed to issue an alarm if the patient is exposed to more than a specified amount of radiation.

Generally, this type of dosimeter uses a primary or secondary battery as its power source, but if the battery runs out, not only will measurement become impossible, but the data that has been stored up to that point will be lost. This can lead to serious accidents, so it is desirable to use batteries that can withstand long-term use and to be able to quickly detect battery depletion, but no measures have been taken to deal with such cases. is the current situation.

This invention has been made in view of these points, and while it issues an alarm when the battery voltage drops below a predetermined value, it also maintains the power supply to the memory at a minimum in order to prevent the loss of stored data. The purpose is to improve the functionality and reliability of dosimeters by minimizing wear and tear.

The feature is that the dosimeter, which is operated by batteries, is equipped with a detection device that detects the state of battery consumption, and when the battery voltage drops below a predetermined value, it issues an alarm and supplies power to other parts except for the memory. This prevents the loss of stored data.

The purpose is to protect it.

Embodiments of the present invention will be described below with reference to the drawings.

Fig. 1 is a block diagram showing the implementation side of the present invention, Fig. 2 is an explanatory diagram illustrating the relationship between the operation of the dosimeter and battery voltage, and Fig. 3 is a flowchart illustrating the operation according to the present invention. .

In Figure 1, 1 is ■10 (input/output device) 11, cp
A microcomputer (hereinafter also simply referred to as a microcomputer) consisting of u (arithmetic control unit) 12, ROM (read only memory) 13, and RAM (random access memory) 14, 2 a battery consumption detection circuit, and 3 an alarm. vessel,
5 is a preamplifier, 4 is a preamplifier switch, 8 is a radiation detector, 6 is a high voltage power source for the detector, and 7 is a high voltage power source switch. Note that the power consumed by the preamplifier 5 and the detector high-voltage power R6 is relatively large, and the power consumed by other circuits is relatively small.

The operation will be explained below with reference to FIGS. 1 and 3.

By turning on a power switch (not shown) (see Figure 3 O), power is supplied to each circuit shown in Figure 1, and radiation dose measurement operations are performed (see Figure 3 O).
0 Here, when the battery voltage falls below a predetermined value, the battery depletion detection circuit 2 detects this (see θ in Figure 3), generates an output S, and puts the microcomputer 1 into standby mode (no longer functions as a microcomputer). However, the stored data is retained) to suppress a decrease in power consumption. At this time, if each function is stopped immediately after the battery voltage falls below a predetermined value, the measured value will become unknown, so the microcomputer 1 outputs a signal and activates the alarm 3 (see ○ in Figure 3). After issuing an alarm to prompt battery charging, the microcomputer 1 is put into standby mode (see Figure 3 ■), and a signal S is issued to preamplifier 5.
and 7 to the switch that drives the high voltage power supply 6 for the detector.
, and then turn off the power. Thereafter, the power from the battery will be consumed only by the memory 13, 14, so the power consumption can be extremely reduced. In other words, the power supply to parts with relatively large power consumption (preamplifier 5, detector high voltage power supply 6) is stopped,
This minimizes power consumption. It goes without saying that charging will take place at a predetermined point thereafter.
Once the charging is completed (see e3 in Fig. 3), it goes without saying that the measurement operation of the dosimeter is restarted (see Fig. 3). As shown in Figure 2, even if the battery voltage rises to the voltage fli VL when the wl source drops, it does not operate immediately, but operates when it reaches ■s, so that the operation of the detection circuit 2 has hysteresis characteristics. do it like this. By doing this, a sufficiently charged battery voltage will be applied to the dosimeter after the power is restored, so not only will the accumulated measurement values that have been held until then be reproducible, but the measurement operation will be started immediately. Begins.

As described above, according to the present invention, when the battery voltage drops below a predetermined value, an alarm is issued to prompt charging, and after that, the consumption of the battery is kept to the necessary minimum, thereby eliminating the loss of measured dose value data. Therefore, its functionality and reliability are significantly improved. For this reason zil! After charging the battery, it is possible to continue measuring by adding it to the previous integrated value.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram explaining the relationship between the operation of the dosimeter and battery voltage, and FIG. 3 is a 70-chart for explaining the operation of the dosimeter. It is. Code explanation 1...Microcomputer for dosimeter, 2...Battery consumption detection circuit, 3...Alarm, 4...
Power switch for preamplifier, preamplifier,
6... High voltage power supply for phase detector, 7... Switch for high voltage power supply, 8... Surface detector, 11... ■10 (
input/output device), 12...CPU (arithmetic control unit), 13.----ROM (read-only memory)
, 14... Song RAM (Random Access Memory) Agent Patent Attorney Akio Namiki Agent Patent Attorney Kiyoshi Matsuzaki 6- Figure 2 □ is the photovoltage Figure 3

Claims (1)

[Claims] A radiation dosimeter comprising a measuring means for measuring a radiation dose by being supplied with power from a battery, and a storage means for storing at least the measured value, the radiation dosimeter comprising a detecting means for detecting a state of exhaustion of the battery. A radiation IIj1M quantity meter, characterized in that when the battery voltage drops below a predetermined value, an alarm is issued and power supply to other parts except the storage means is stopped to protect the stored contents.