JPH0810164B2 - Electronic thermometer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a guess type electronic thermometer, and more particularly to an electronic thermometer having a function of reading and notifying a measured body temperature.

(B) Conventional technology In the conventional guess-type electronic thermometer, when several measured data are obtained, the equilibrium body temperature is also estimated each time the measured temperature is measured, and this estimated value is displayed. For example, a device that displays the actual measured temperature until then is displayed by switching it to an estimated value, and at the time of this display switching the buzzer is operated to notify that the estimated value has been displayed. is there.

(C) Problems to be Solved by the Invention Since the conventional guess-type electronic clinical thermometer described above performs simultaneous display of the estimated value of the notification by the buzzer operation, if the estimated value displayed at this time is read as the body temperature, There is a problem that the accuracy of the measured body temperature is not good because the accuracy of the estimated value is not high. In order to improve the accuracy, it is sufficient to read the display after a predetermined time has passed after the operation of the buzzer, but it was inconvenient for the measurer because there was no indication of how long it should take.

In order to solve this problem, it is possible to make a notification when the difference between the estimated value and the measured value reaches a predetermined value, or when the timer measures a predetermined time after the estimated value is obtained. In order to improve the accuracy, the temperature change characteristics, that is, the response curve has large variations depending on the ambient temperature, the physical constitution of the person to be measured, the measurement site, etc., and the notification is made according to the difference between the estimated value and the actually measured value. When the set value is made small, the measurement time greatly varies, and the measurement time becomes extremely long especially in the characteristic of slow response. On the other hand, in the case where the notification is given after a predetermined time has elapsed after the estimated value is obtained, the accuracy varies from measurement to measurement.

In view of the above, the present invention provides an electronic clinical thermometer capable of highly accurate measurement for most of general response curves and capable of performing measurement with a certain measurement time for slow response characteristics. It is intended to be provided.

(D) Means and Actions for Solving Problems The electronic clinical thermometer according to the first aspect of the present invention measures the actual temperature at every predetermined cycle, as shown in the schematic configuration in FIG. Temperature measuring means 1, storage means 2 for storing the measured temperature, guess value calculating means 3 for estimating the equilibrium body temperature based on the measured temperature, display means 4 for displaying the measured temperature or the estimated value, and the temperature measurement. A discriminating means 5 for discriminating that the difference value between the actual measurement value obtained by the means and the estimation value obtained by the estimation value calculation means has reached a preset predetermined value; and after the difference value reaches the predetermined value. It comprises a timer 6 for measuring a certain period of time and an informing means 7 driven when the certain period of time elapses.

The electronic clinical thermometer according to the second aspect of the present invention has substantially the same configuration as the electronic clinical thermometer described above, except for the determining means and the timer. That is, the determination means determines that the temperature increase rate has dropped to a predetermined value or less, and the timer has a fixed time after the determination means determines that the temperature increase rate has decreased to a predetermined value or less. Is to keep time.

In this electronic thermometer, when the estimated value is calculated by the estimated value calculating means, this is displayed on the display means. Then, the discriminating means discriminates whether the response value of the response curve (the difference value between the measured value and the estimated value or the temperature increase rate) has reached a predetermined value. When the value reaches the predetermined value, it means that the time point at which the estimation with substantially the same accuracy is obtained regardless of the difference in the response curves. From this time point, the notification means is driven after a lapse of a fixed time measured by the timer. Upon receiving this notification, the measurer reads the estimated body temperature on the display means.

(E) Examples Hereinafter, the present invention will be described in more detail with reference to Examples.

<Embodiment 1> FIG. 2 is a block diagram of an electronic thermometer showing an embodiment of the present invention. The temperature sensor 11 includes a temperature sensitive element such as a thermistor, detects the body temperature of the measurement site at a predetermined sampling cycle, and is taken into the CPU 13 via the A / D converter 12. The actual body temperature data obtained at each sampling cycle is stored in the memory 14 under the control of the CPU 13.

The CPU 13, along with the temperature sensor 11 and the A / D converter 12, tests the temperature measurement function of actually measuring the current temperature at each sampling cycle, the estimation value calculation function of estimating the equilibrium body temperature, and the difference between each estimation value and the actual measurement value. It is provided with a function of calculating a value, a function of determining that the difference value has reached a predetermined value (eg, 1.5 ° C), a timer function of measuring a certain time from the determination time, and the like.

Further, the actually measured body temperature and the estimated body temperature are displayed on the display unit 15, and necessary information is given by the operation of the buzzer 16.
In addition, this electronic thermometer includes a power battery 17 and a power switch 18. However, the hardware configuration shown in FIG. 2 is the same as that of a general electronic thermometer known in the related art.
The electronic thermometer of this embodiment is characterized by the functional configuration of the CPU 13.

Therefore, the software configuration and operation of the electronic thermometer of this embodiment will be described below with reference to the flowchart shown in FIG.

When the power switch 18 is turned on and the operation is started, first, an initialization process such as setting the flag F to 0 is performed [step ST (hereinafter referred to as ST) 1], and then the temperature sensor 11 is supplied at each sampling time (ST2). , The current temperature T (t) is read through the A / D converter 12 (ST3). Then, the temperature T (t) is stored in the memory 14 (ST4). On the other hand, the following operations are performed at each sampling time, and ST2
Return to The sampling time is 1 second in the embodiment.

Following storage of the temperature T (t), it is determined in ST5 whether or not estimation is possible. This determination is specifically YES, for example, 40 seconds after the start of measurement. After 40 seconds,
This is because the parameter P described later is calculated. At the beginning of the measurement, this determination is NO, and subsequently it is determined whether or not the parameter P can be calculated (ST6). This parameter P
Is calculated as a ratio of change rates when a response curve (change curve of detected temperature) is drawn. And this parameter P
Is within the preset range (0.38 to 0.68),
It is determined whether or not the temperature change with time is recognized as that at the time of measuring the body temperature.

The parameter P is calculated based on the following equation.

In this equation, T is the detected temperature and t is the time.

As specific values, the parameter P is calculated at t ₀ = 20 seconds, t ₁ = 30 seconds, and t ₂ = 40 seconds. Therefore, until 40 seconds have elapsed from the start of measurement, the determination in ST6 also becomes NO, then the process proceeds to ST7, and it is determined whether or not the current measured temperature T (t) is 32 ° C. or higher.

If the ambient temperature is low and the measured temperature T (t) has not reached 32 ° C., the determination in ST7 is NO, and the display unit 15 displays the letter L indicating a low temperature. That is, as shown in FIG. 4, the letter L is displayed from the start of measurement to point a.

When the thermometer is attached to the body and the measured temperature T (t) rises and reaches 32 ° C as indicated by point a in Fig. 4, the determination in ST7 is YES, the process moves to ST11, and the measured temperature is displayed on the display 15. T
(T) is displayed. After that, the processes of ST2 to ST7, ST11, and ST9 are repeated until 40 seconds after the start of the measurement, and the measured temperature T (t) displayed on the display 15 increases (a to b in FIG. 4). See point).

When 40 seconds have elapsed after the start of measurement, the data for calculating the parameter P are gathered, so the determination in ST6 is YES, the response curve analysis, that is, the calculation of the parameter P is performed (ST10), and the measured temperature is still displayed on the display 15. Is displayed (ST11), ST
Return to 2.

At the next sampling time, the parameter P has already been obtained, so the "guess?" Judgment in ST5 becomes YES, and then the parameter P falls within the predetermined range (0.38≤P≤0.68).
It is determined whether it is within. That is, it is determined whether the parameter P is within the data range of the clinical result. If P>
When it is 0.68, it means a rapid temperature rise other than body temperature measurement, and when P <0.38, it means that it is a gradual temperature rise. In any case, it is assumed that the measurement is other than the body temperature, and in this case, even if the estimation value calculation is performed, an appropriate value cannot be obtained, so the measurement is not performed and the actual measurement temperature T (t) is displayed (ST11).

On the other hand, if the parameter P is within the set value range (it is recognized as the predetermined body temperature measurement), the determination in ST12 is YES, and the estimation value S (t) is calculated in ST13. This guess S
(T) is calculated based on the following equation.

S (t) = T (t) + [a (t + b) ² + c] dT / dt In this estimation formula, T (t) is the measured temperature at the sampling timing when t hours have elapsed from the start of measurement, and the measured temperature T (T), the measurement time t, and the rate of increase of the measured temperature dT / dt at this sampling timing are the calculation factors. In addition, a (-0.002), b (-200), c
(30) is a constant multiplier.

Following the calculation of the estimated value S (t), the difference value ΔT between the estimated value S (t) and the measured temperature T (t) is calculated (ST14), and this difference value ΔT is within a predetermined value α (= 15 ° C). It is determined whether or not (ST
15). If the difference value ΔT does not reach within 1.5 ° C,
The estimated value S (t) is displayed on the display 15 (ST20). This estimated value display is the display between b and c in FIG. 4, but at this stage, the slow speed of the response curve has not been absorbed,
This guess is not very accurate.

If the measured temperature T (t) rises and the difference value ΔT with the estimated value S (t) eventually reaches 1.5 ° C, the determination in ST15 is YES.
Then, it is determined whether or not the flag F is in the 0 state, that is, whether or not the timer ts is activated (ST16). ST1
Since the instrument is still initialized and the flag F is in the 0 state, this determination becomes YES, and then at ST17, the timer ts
Is activated and the flag F is set to 1 (see point c in FIG. 4). Subsequently, it is determined whether or not the timer ts has timed out (ST18), and from the point c, that is, the difference value ΔT is 1.
If time ts has not elapsed since the temperature reached 5 ° C, ST1
The judgment of 8 becomes NO, and the guess value S (t) continues to be displayed (S
T20), return to ST2. Since the flag F is set to 1 after the timer ts is started, the determination in ST16 is NO, and ST17 is skipped.

When the timer ts times out, the determination in ST18 becomes YES, the buzzer 16 turns on (ST19), and the reading of the estimated value displayed on the display 15 is notified.

The response curve shown in Fig. 4 exemplifies the case of a person who has a relatively rapid rate of increase. In this case, the difference between the estimated value and the actual measured value at the time point of ts is about 0.5 ° C. Get closer to. Therefore, the measurer can obtain a highly accurate measured value in a short time by listening to the notification sound of the buzzer 16 and reading the estimated value.

The response curve shown in FIG. 5 exemplifies the case of a measurer having a relatively slow increase rate, and in this case, it takes a considerable amount of time for the difference value to reach a predetermined value from the example shown in FIG. It depends. Furthermore, the difference between the measured value and the estimated value at the end of the timer is about 0.9 ° C. In this case, the guess value with some credibility can be displayed within a relatively short time.

Second Embodiment FIG. 6 shows a partial flow chart for explaining the software configuration and operation of the electronic thermometer of the second embodiment.

In this embodiment, the electronic thermometer detects when the difference between the estimated value and the measured value reaches 1.5 ° C. in the first embodiment, whereas the temperature rise rate β at the position corresponding to this difference value 1.5 ° C. It is determined whether or not the temperature rise rate dT / dt at the sampling timing has decreased below a predetermined value)
The timer ts is started from this time. Therefore, the flow chart also corresponds to ST12 to ST18 in FIG.
In the figure, ST12 to ST18 are replaced, and other processing is exactly the same. That is, when it is determined in ST12 that the parameter P is within the predetermined range, the estimated value S (t) is subsequently calculated (ST13), and the temperature increase rate dT / dt is calculated (ST1).
4) It is determined whether this rate of increase is within a predetermined value (β) (S
T15), when it falls within a predetermined value, the timer ts is started (ST1
7) I am doing so.

In the electronic thermometer of this embodiment, as shown in FIG. 7, L is displayed from the start of measurement to point a, actual measurement is displayed from point a to point b at which a guess value can be calculated, and guess value is displayed after point b. . On the other hand, a timer ts
Is activated, and a notification is given by a buzzer sound at the time point d of the timer ts.

In the above embodiment, the temperature sensor, the A / D converter, the CPU, etc. are used to measure the body temperature, but the present invention is not limited to this. You may use the temperature measuring device of this.

(F) Effect of the Invention In the present invention, the difference value between the actual measurement value and the estimated value or the actual temperature increase rate is monitored on the assumption that the convergence temperature is estimated and the measurement time is shortened. In the case of, the difference value reaches a predetermined value, and in the case of the measured temperature rise rate, the measured temperature rise rate decreases below the predetermined value, and both ends the measurement after a fixed time, that is, from the start of measurement. When the difference value or the measured temperature rise rate has calmed down to some extent,
Since the final temperature is estimated and the measurement is completed, the estimation error can be reduced. Therefore, a highly accurate guess value can be obtained for a response curve with a fast response, and a guess value with a certain degree of accuracy can be obtained for a response curve with a slow response in a relatively short time. It can be expanded.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of the invention, and FIG. 2 is a circuit block diagram of an electronic thermometer showing an embodiment of the invention.
FIG. 3 is a flow chart for explaining the software configuration and operation of the electronic thermometer of the same embodiment, and FIGS. 4 and 5 are diagrams for explaining changes in measured temperature and display states of the electronic thermometer of the same embodiment,
FIG. 6 is a partial flow chart for explaining the software configuration and operation of the electronic thermometer of the second embodiment, and FIG. 7 is a diagram for explaining the measured temperature change and display state of the electronic thermometer of the same embodiment. . 1: temperature measurement means, 2: measured temperature storage means, 3: guess value calculation means, 4: display means, 5: determination means, 6: timer, 7: notification means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 61-3018 (JP, A) JP 61-3017 (JP, A) JP 58-211610 (JP, A) Actual development Sho 59- 135441 (JP, U)

Claims (2)

[Claims] 1. A temperature measuring means for actually measuring a current temperature for each predetermined cycle, a storage means for storing the measured temperature, an estimated value calculating means for estimating an equilibrium body temperature based on the actually measured temperature, and the actually measured temperature or the estimated value. Display means for displaying a value, a discriminating means for discriminating that the difference value between the measured value obtained by the temperature measuring means and the estimated value obtained by the estimated value calculating means has reached a preset predetermined value, An electronic thermometer comprising a timer for measuring a fixed time after the difference value reaches a predetermined value, and an informing means driven when the predetermined time elapses. 2. A temperature measuring means for actually measuring a current temperature in a predetermined cycle, a storage means for storing the measured temperature, an inferred value calculating means for inferring an equilibrium body temperature based on the actually measured temperature, and the actually measured temperature or inferred value. Display means for displaying a value, determination means for determining that the temperature increase rate has dropped below a predetermined value, and a predetermined time period after this determination means determines that the temperature increase rate has dropped below a predetermined value. An electronic clinical thermometer comprising a timer for measuring the time and an informing means driven when the predetermined time has elapsed.