JPS60142225A - Electronic clinical thermometer - Google Patents

Abstract

PURPOSE:To save a power consumption by providing a temperature measuring and oscillating circuit whose oscillation frequency is varied by a temperature, and a measuring circuit for converting the oscillation frequency of this oscillating circuit to a temperature. CONSTITUTION:At temperature measuring and oscillating circuit 1 is constituted so that a power source is turned on automatically when its temperature measuring part is pinched, for instance, by the armpit, by which a measuring command pulse S1 is inputted to the temperature measuring and oscillating circuit 1 from a timer counter 3. Also, an instrumentation circuit 4 is constituted so that the number of output pulses S2 is counted by a counter contained in it and can be converted to a temperature. Accordingly, after a prescribed time for reading a person's temperature after starting to take his temperature has elapsed, an oscillation of the temperature measuring and oscillating circuit 1 and a clock oscillating circuit 2 is stopped automatically, and a power consumption can be saved by setting the whole LSI circuit to a static state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electronic thermometer that electronically measures body temperature.

[Technical background of the invention and its problems]

Conventionally, commonly used electronic thermometers are equipped with a slide switch to turn the power on and off, and the power is turned off by operating the slide switch when temperature measurement is complete. However, operating such a slide switch is extremely troublesome, and force is often wasted due to forgetting to turn off the switch.

Electronic thermometers in general homes are often used in emergencies when a person has a fever, and there is a risk that they will become unusable in an emergency if the battery dies due to forgetting to turn it off. In addition, since the usage range is high in the case of hospital use, there is a high possibility that the battery will run out if the device consumes a large amount of power.

To avoid running out of battery due to wasted power, use the L for thermometer.
A switching transistor that controls the power on and off is installed in the SI, and the power is automatically turned off after a predetermined period of time (for example, the time required to measure the temperature and read the body temperature display). Measures to prevent this have been proposed.

However, the switching transistor that controls the on/off of the power source occupies a large area on the LSI chip, which is disadvantageous in reducing the size and cost of the LSI.

In addition, in hospitals where the time it takes to read the body temperature display is uncertain, if the power is automatically turned off after a predetermined period of time has passed from the start of temperature measurement, the power may turn off before the body temperature display can be read. It was quite inconvenient.

[Purpose of the invention]

The present invention was made to solve the above problems, and an object of the present invention is to provide an electronic thermometer that can reduce power consumption.

[Summary of the invention]

This invention utilizes the characteristic of consuming low power in a dynamic state such as in a CMO8 or LSI, but not consuming power in a static state.

That is, this invention utilizes the fact that the oscillation frequency of the temperature measurement oscillation circuit in the thermometer LSI is proportional to the temperature, converts the output signal into temperature in the measurement circuit, and then displays the result through the display circuit. The LSI is characterized in that the LSI is controlled in a static state by displaying the temperature, and stopping the oscillation of at least one of a clock oscillation circuit that outputs a display clock and a temperature measurement oscillation circuit after a certain period of time has elapsed from the start of temperature measurement. be.

〔Effect of the invention〕

The present invention can prevent wasteful power consumption by automatically controlling at least one of the clock excavation circuit and the dl11 temperature oscillation circuit to a static state after a certain period of time has elapsed from the start of temperature measurement. In particular, in the case of a thermometer used in a hospital, by controlling only the temperature measurement oscillation circuit to a static state, it is possible to display body temperature over a long period of time while reducing power consumption.

[The Fruit of Invention II] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a temperature measurement oscillator circuit whose excavation frequency changes depending on the temperature, and a clock pulse S is applied to the temperature measurement section'counter 3 of this oscillation circuit 1. At the same time, a measurement command pulse S is input from the timer counter 3 to the measurement unit oscillation circuit 1. As shown in FIG. 2, this oscillation circuit 1 consists of a linear thermistor 101 whose resistance value changes in proportion to temperature.
Capacitor 102. It is composed of an inverter 103 and a NANI gate 104. When a measurement command pulse S1 with a constant time width of l'1 is input from the timer counter 3 to the NANIJ gate 104 as shown in FIG. As shown in Figure 3 (bl), the oscillation of the output pulse S2 is started, and the oscillation of the output pulse S is stopped at the falling edge of the measurement command pulse SI.The output pulse S2 of the side temperature oscillation circuit 1 is proportional to the frequency of the temperature. Therefore, output during measurement command pulse width T)<? ) Calibrate in advance so that the number of responses S2 corresponds to the temperature. In this way, the number of output pulses S2 can be counted by the counter in the measurement circuit 4 and converted into temperature. The results of this measuring circuit 4 are displayed on, for example, an LCD 6 via a display circuit 5.

If such an operation is performed for a certain period of time from the start of temperature measurement until the temperature is read, the measurement command pulse S always becomes "0", so the side temperature oscillation circuit 1 stops excavation and IF. At the same time, the clock oscillation circuit 2 stops oscillating in response to the output pulse S3 from the timer counter 3.

Therefore, according to such a configuration, the temperature measurement oscillation circuit 1
Also, since the oscillation of the clock oscillation circuit 2 can be automatically stopped, all LSI circuits can be kept in a static state and power consumption can be reduced.

On the other hand, in the case of an electronic thermometer for hospital use, there is no fixed time period for reading the body temperature after temperature measurement, so it cannot be used with a short readable time as in the above embodiment.

Therefore, in another embodiment of the present invention, only the temperature measurement oscillation circuit is stopped after a certain period of time required for temperature measurement has elapsed, so that a part of the LSI is placed in a static state. In this way, it is possible to reduce power consumption and enable long-time reading in hospital applications.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without changing the gist.

In the above embodiment, a temperature measurement oscillation circuit using a thermistor was used, but the present invention is not limited to this, but is an excavation circuit whose oscillation frequency changes depending on the temperature and which is capable of on/off control of oscillation. You can use it if you have it. Furthermore, the clock generation circuit is not limited to the C-type oscillator, and any oscillation circuit that can control oscillation on and off as described above may be used as appropriate.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a schematic circuit configuration of an electrical IM example of the present invention, FIG. 2 is a circuit configuration diagram of a measurement oscillation circuit which is the main part of the same embodiment, and FIG. FIG. 3 is a waveform diagram for explaining the operation of the oscillation circuit of FIG. 1... Temperature measurement oscillation circuit 2... Clock excavation circuit 3... Timer counter 4... Measurement circuit 5... Display circuit 101... Linear thermistor 102... Capacitor 103... Inverter 10
4...NAND gate 1st Figure 9 Figure 2 Figure 3

Claims (3)

[Claims] (1) A temperature measurement oscillation circuit whose excavation frequency changes depending on the temperature, a measurement circuit that converts the excavation frequency of this oscillation circuit into temperature, a display circuit that displays the output of this measurement circuit, and a clock oscillation circuit that outputs a display clock. 1. An electronic thermometer comprising: a circuit; and oscillation stopping means for stopping excavation of at least one of the side temperature oscillation circuit and the clock oscillation circuit after a certain period of time has elapsed from the start of temperature measurement. (2) The electronic thermometer according to claim 1, wherein the oscillation stopping means stops the oscillation of the temperature measurement oscillation circuit and the clock oscillation circuit after a certain period of time has elapsed from the start of temperature measurement. (3) The electronic thermometer according to claim 1, wherein the excavation stop means causes the trowel to stop oscillating the clock excavation circuit after a certain period of time has elapsed since the start of temperature measurement.