JP2003121265A - Electronic clinical thermometer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a bodily temperature measured only under a proper condition to prevent measuring precision from lowering. SOLUTION: This electronic clinical thermometer of the present invention using an infrared sensor 41 has a first thermosensitive device for measuring a temperature of the infrared sensor 41 itself, a second thermosensitive device 20 for measuring an ambient temperature, and an alarm means 2 for issuing a measurement-impossible alarm when a measured value difference between the first thermosensitive device and the second thermosensitive device exceeds an allowable value. The measurement-impossible alarm is issued thereby under the condition where measuring precision of the infrared sensor 41 gets low, so as to allow the bodily temperature measurement only under the proper condition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electronic thermometer using an infrared sensor.

[0002]

2. Description of the Related Art An infrared sensor usually used in an ear type electronic thermometer has an advantage that the measuring time is very short (measuring time: several seconds). However, the infrared sensor has a drawback that the measurement accuracy is deteriorated when the temperature of the infrared sensor itself changes in a short time due to heat generation or the like. In order to make up for this drawback, the infrared sensor is generally attached to a member having a good heat dissipation property, and is configured so that the temperature change of the infrared sensor itself with respect to the ambient temperature becomes small.

[0003]

However, if the thermometer is used more frequently or the ambient temperature rises, the temperature of the infrared sensor itself may rise above the permissible value with respect to the ambient temperature. If the measurement is continued in such a state, a correct measured value cannot be obtained. The present invention has been made in view of the above problems, and an object of the present invention is to make it possible to measure a body temperature under appropriate conditions and prevent a decrease in measurement accuracy.

[0004]

The above-mentioned problems can be solved by the inventions of the respective claims. The invention of claim 1 is an electronic thermometer using an infrared sensor, comprising: a first temperature sensitive element for measuring a temperature of the infrared sensor itself; a second temperature sensitive element for measuring an ambient temperature; It is characterized in that it has an alarm means for issuing a measurement impossible alarm when the difference between the measured values of the temperature sensitive element and the second temperature sensitive element exceeds an allowable value.

According to the present invention, when the temperature of the infrared sensor itself exceeds the permissible value with respect to the ambient temperature, the alarm means issues a non-measurable alarm. That is, under the condition that the measurement accuracy of the infrared sensor is lowered, a measurement impossible alarm is issued, and the body temperature can be measured only under the proper condition. In this way, since it becomes possible to measure body temperature only under appropriate conditions,
It is possible to prevent a decrease in measurement accuracy.

Further, as described in claim 2, by installing the second temperature sensitive element in a state where the temperature from the human body is difficult to be transmitted, the ambient temperature can be accurately measured by the second temperature sensitive element. Become.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an electronic clinical thermometer according to a first embodiment of the present invention will be described with reference to FIGS. The electronic clinical thermometer according to the present embodiment is an ear thermometer that measures the eardrum temperature with an infrared sensor. FIG. 1 shows an overall longitudinal sectional view of the ear thermometer, and FIG. 2 shows an external view of the ear thermometer. . As shown in FIG. 1, the ear thermometer 1 according to the present embodiment (hereinafter referred to as the thermometer 1) includes a temperature measuring unit 4 and a main body unit 2.

The temperature measuring section 4 is a section for detecting the amount of infrared rays radiated from the eardrum or the like. For example, an infrared sensor 41 such as a thermopile or a pyroelectric sensor (hereinafter referred to as sensor 4).
1)). Further, the sensor 41 has a first temperature sensitive element (not shown) incorporated therein for measuring the temperature of the sensor itself. Here, for example, a thermistor or the like is used as the first temperature sensitive element.

The sensor 41 is attached to the end of the substrate 5, and the cylindrical waveguide 4 is attached to the tip of the sensor 41.
The two base ends are connected. The waveguide 42 uses the sensor 41 to detect infrared rays incident from an infrared ray entrance 45f described later.
It is a tubular body that leads up to, and is generally made of copper plated with gold.

The periphery of the base ends of the sensor 41 and the waveguide 42 is covered with a tapered cylindrical support member 43, and the base end of the support member 43 is fixed to the substrate 5. The support member 43 is a member that supports the sensor 41 and the waveguide 42 and stabilizes the temperature of the sensor 41, and is generally made of an aluminum alloy. Support member 43
And the periphery of the waveguide 42 protruding from the supporting member 43 are covered with an inner cap 44 made of ABS resin, for example. Further, the periphery of the inner cap 44 is covered with a sensor cap 45 that constitutes the housing of the temperature measuring unit 4.

The outer diameter of the base end of the sensor cap 45 is set to be slightly smaller than the inner diameter of the opening 7h formed in the body case 7 of the thermometer 1. For this reason,
With the sensor cap 45 covered with the inner cap 44, as shown in FIG. 1, the base end portion of the sensor cap 45 is inserted into the opening 7h of the main body case 7 by a predetermined dimension. The sensor cap 45 and the like are covered with a cup-shaped protective case 8 when the thermometer 1 is not used.

The body part 2 of the thermometer 1 is a part for calculating the body temperature based on the amount of infrared rays detected by the sensor 41 of the temperature measuring part 4 and displaying the calculated value. The microcomputer and the display 12 , An ON / OFF switch 14 and the like. Microcomputer,
The display 12 and the like are attached at predetermined positions on the substrate 5,
The substrate 5 is attached to substantially the center of the body case 7 in the thickness direction.

A second temperature sensitive element 20 for measuring the ambient temperature is attached to the substrate 5 in a state of being surrounded by the display 12. As described above, since the second temperature sensitive element 20 is attached to the substrate 5 in a state of being surrounded by the display 12, the second temperature sensitive element 20 influences the temperature of the human body when the thermometer 1 is used. It is difficult to receive. Therefore, the second temperature sensitive element 20 can accurately measure the ambient temperature. Here, for the second temperature sensitive element 20, for example, a thermistor or the like is used.

The signal from the second temperature-sensitive element 20 is A / D converted together with the signal from the first temperature-sensitive element described above, and then input to a microcomputer, which compares the measured values of both signals. It Then, when the difference between the measured values of the two temperature sensitive elements is larger than the allowable value, a measurement impossible alarm is issued.

Here, the infrared sensor 41 has a drawback that the measurement accuracy is lowered when the temperature of the sensor itself changes in a short time due to heat generation or the like. However, when the difference between the measured values of the two temperature sensitive elements is larger than the allowable value, for example, when the temperature of the sensor itself exceeds the ambient temperature by more than the allowable value, the measurement impossible alarm is issued. Therefore, the body temperature is not measured under the condition that the measurement accuracy of the sensor 41 is lowered, and the body temperature can be measured only under the proper condition of the sensor 41. Here, the allowable value is set to 1 ° C., for example. That is, the microcomputer of the main body 2, the display 12 and the like correspond to the alarm means of the present invention.

Next, the handling of the above-mentioned thermometer 1 will be described. First, the ON / OFF switch 14 of the thermometer 1
Turn on. At this time, if the difference between the measured values of the first temperature sensitive element and the second temperature sensitive element 20, that is, the temperature difference between the temperature of the sensor 41 itself and the ambient temperature exceeds an allowable value, measurement is impossible. An alarm is issued. In this case, the content of the body temperature measurement after about a few minutes is displayed. Also,
When the ON / OFF switch 14 of the thermometer 1 is turned on and the temperature difference between the temperature of the sensor 41 itself and the ambient temperature is within the allowable value, the measurement impossible alarm is not displayed and the body temperature can be measured.

In this case, the sensor cap 45 of the thermometer 1 is inserted into the ear canal. As a result, infrared rays radiated from the eardrum or the like are transmitted through the infrared ray entrance port 45 of the sensor cap 45.
f, guided to the sensor 41 via the waveguide 42. The sensor 41 detects the dose of infrared rays (infrared ray amount) guided from the infrared ray incident port 45f through the waveguide 42. Then, the microcomputer calculates the body temperature based on the infrared ray amount detected by the sensor 41, and the calculated value is displayed on the display 12
Is displayed in.

As described above, in the thermometer 1 according to this embodiment, when the temperature of the sensor 41 itself exceeds the permissible value with respect to the ambient temperature and rises, an alarm for measuring is issued by the alarm means. That is, under the condition that the measurement accuracy of the sensor 41 deteriorates, the measurement impossible alarm is issued, and the body temperature can be measured only under the proper condition. As described above, since the body temperature can be measured only under appropriate conditions, it is possible to prevent the measurement accuracy from deteriorating.

Further, since the second temperature sensitive element 20 is attached to the substrate 5 in a state of being surrounded by the display 12, the second temperature sensitive element 20 indicates the temperature of the human body when the thermometer 1 is used. Not affected. Therefore, the ambient temperature can be accurately measured. The second temperature sensitive element 20
Although the example is shown in which it is attached to the substrate 5 while being surrounded by the display 12, it can be attached at a position apart from the display 12 if it is not affected by the temperature of the human body. In the present embodiment, the ear thermometer 1 has been described as an example, but a thermometer other than the ear thermometer can be applied as long as the thermometer uses an infrared sensor.

[0020]

According to the present invention, since the body temperature can be measured under appropriate conditions, it is possible to prevent the measurement accuracy from deteriorating.

[Brief description of drawings]

FIG. 1 is an overall vertical sectional view of an electronic thermometer according to a first embodiment of the present invention.

FIG. 2 is an external view of an electronic thermometer.

[Explanation of symbols]

2 Main body (alarm means) 4 Temperature measuring unit 20 Second temperature sensor 41 Infrared sensor (Built-in first temperature sensor) 42 Waveguide 45 sensor cap

Claims (2)

[Claims] 1. An electronic thermometer using an infrared sensor, comprising: a first temperature sensitive element for measuring a temperature of the infrared sensor itself; a second temperature sensitive element for measuring an ambient temperature; and a first temperature sensitive element. An alarm means for issuing a measurement impossible alarm when the measured value difference between the element and the second temperature sensitive element exceeds the allowable value,
An electronic thermometer characterized by having. 2. The electronic thermometer according to claim 1, wherein the second temperature sensitive element is installed in a state in which the temperature from the human body is difficult to be transmitted.