JPH04184240A - Gravimeter - Google Patents

Abstract

PURPOSE:To simply and rapidly measure the specific gravity of a living body by quantitatively supplying gas different from the gas present in an airtight container and inert to an object to be measured into the airtight container in which the object to be measured is received to analyze the concn. of the gas in the container. CONSTITUTION:A living body to be measured is received in an airtight container 2 whose internal volume is known and the body wt. thereof is calculated by a body-weight measuring scale 14 and, subsequently, a definite amount of gas different from the gas uniformly present in the container 2 and inert to the living body to be measured is supplied into the container 2 and the concn. of this supplied gas is measured. Then, accurate volume can measured based on such a theory that the concn. of the supplied gas in the container becomes high by the volume of the living body to be measured. That is, the volume can be measured with high accuracy without injuring respiratory function and measuring lung residual air quantity. By this method, the specific gravity of the living body can be simply and accurately measured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an apparatus for measuring the specific gravity of an object to be measured, such as a human body, using gas.

[Prior Art] Measuring the specific gravity of the human body is essential for calculating body fat percentage and determining whether a person is overweight or underweight. However, a means for simply measuring the specific gravity of the human body is surprisingly unknown and little development has been done. Therefore, to determine whether someone is too fat or too thin, it is still necessary to calculate [height - 110 cm or [height x
The subcutaneous fat percentage is calculated using empirical and statistical methods such as 0.9-100, or using a sebum thickness meter or an ultrasound diagnostic device. This is the reality.

A conventionally known method for measuring the specific gravity of the human body is a method of directly measuring body specific gravity using the underwater weight method. This is known as Archimedes' principle, which states that when an object to be measured is submerged in a liquid whose specific gravity is known in advance, the buoyant force in the liquid is equivalent to the weight of the liquid for the object's volume. Therefore, the volume is determined by subtracting the gravity (wb) of an object in liquid from the weight (Wa) of the object in the atmosphere.

[Problems to be Solved by the Invention] However, with the underwater weight method, the volume must be measured while a person is submerged underwater and exhaled as much air as possible from the lungs. It is necessary to separately measure and correct by He dilution method, which causes great pain to the subject and requires a specialist, so there are problems that it has not been put to practical use.

SUMMARY OF THE INVENTION In order to solve the problems of the prior art described above, an object of the present invention is to provide a hydrometer that can easily and quickly measure the specific gravity of a living body such as a human body.

[Means for Solving the Problems] In order to achieve the above object, the hydrometer of the present invention includes a means for measuring the weight of an object to be measured, an airtight container in which the object to be measured is placed, and a container into the airtight container. and a gas concentration analysis means for analyzing the gas concentration in the airtight container, and a gas other than the gas present in the airtight container is supplied into the airtight container in which the object to be measured is placed. A type of gas,
The object to be measured is characterized in that a constant amount of inert gas is supplied and the gas concentration in the airtight container is analyzed.

In the above, it is preferable that the object to be measured is a human body.

[Operation] According to the configuration of the present invention, since the means for measuring the weight of the object to be measured is provided, the weight (
W) can be found first.

Next, the object to be measured (for example, a human body) is placed in an airtight container with a known internal volume, and the gas to be measured is of a different type than the gas initially uniformly present in the airtight container. The object is a fixed amount of inert gas supplied or generated in an airtight container, and then the concentration of the supplied gas is measured, so the concentration of the supplied gas in the airtight container is equal to the volume of the object to be measured. Due to the principle that the volume increases, accurate volume measurement can be performed. That is, measurement can be performed without inhibiting respiratory function, and highly accurate volume measurement can be performed without requiring measurement of residual capacity of the lungs. Thereby, the volume (V) for calculating the specific gravity can be determined.

As a result, the specific gravity (D) can be determined by the formula [weight (W)/volume (V)].

[Example 1] An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a hydrometer that is an embodiment of the present invention. In Fig. 1, 1 is a specific gravity measuring device, 2 is an airtight container with a known internal volume for placing a human body as an object to be measured, and 3 is a gas concentration analyzer for analyzing the gas concentration inside the airtight container 2. 4 is a gas supply means such as a gas cylinder for supplying gas into the airtight container 2, 5 is a metering means for supplying gas, 6 is a microcomputer section, 7 is a common power source, 8
1 is a measurement start switch, 9 is an electromagnetic valve, 10 is a rotary valve, 11 is a measuring tube, 12 is a fan for stirring the gas in the airtight container 2, 13 is a display device, and 14 is a weight scale.

The operation of the specific gravity measuring device 1 configured as described above will be explained below.

■ First, a human body, which is an object to be measured, is placed in an airtight container 2. The weight (W) is determined by the scale 14 and recorded in the microcomputer section 6.

(2) Measurement is started by turning on the measurement start switch 8 attached to the microcomputer section 6.

The solenoid valve 9 of the gas supply device 4 is opened according to a command from the microcomputer section 6.

(2) A known gas different from the gas present in the airtight container 2 is prepared in the gas supply device 4, and this gas is fed into the airtight container 2 through the gas metering section 5. Note that the supply gas is preferably a single gas component in order to facilitate concentration measurement. For example, H6,, ArXN
The type, such as e, does not matter. The supply gas is the object to be measured and an inert gas. Since the human body is handled, gases that are toxic to the human body cannot be used, and even when rare gases are used, multiple safety devices are installed and the amount used is small (for example, less than ppm order). It is preferable that

(2) The gas metering section 5 sends out gas flowing into the metering tube 11 when the rotary valve 10 is switched as shown in FIGS. 2(a) and 2(b). The gas pressure inside the metering tube 11 is equal to atmospheric pressure, and the amount of gas supplied is constant depending on the internal volume of the metering tube 11.

Here, the rotary valve 10 shown in FIGS. 2(a) and (b)
The effect of this will be explained in detail.

First, before volume measurement, as shown in FIG. 2(a), the gas in the airtight container 1 is circulated from pipeline E to pipeline A to pipeline F using a gas distribution means such as an air pump (not shown). let The supplied gas (inert gas) from the gas cylinder is circulated from pipeline G→pipeline B→metering pipe 11→pipeline C→pipeline H.

Next, as shown in FIG. 2(b), the rotary valve 10 is turned counterclockwise by 1/6 turn. As a result, the flow of gas in the airtight container 1 is as follows: pipeline E → pipeline B → measuring pipe 11 → pipeline A → pipeline F, and the gas in the measuring pipe 11 is accurately sent into the airtight container 1. .

Note that gas from the gas cylinder flows as follows: pipeline G→pipeline C→pipeline H.

In this way, a fixed amount of supply gas can be fed into the airtight container 2.

■ The supply gas sent into the airtight container 2 is passed through the fan 1.
2 to uniformly stir or spread.

Starting and stopping of the fan 12 can also be controlled by the microcomputer section 6.

(2) After uniformly stirring the supplied gas, the concentration of the gas in the airtight container 2 is measured. The gas to be measured is the supply gas. Concentration measurement involves sampling a uniform gas in an airtight container and analyzing it with a concentration analyzer.

Sampling and concentration measurement are preferably performed automatically under the control of the microcomputer section 6.

■ Based on the measured concentration value, calculate the volume of the object to be measured using the following formula.

v=Vo+vl (α1-1)/(α1-α0) However, each symbol is as follows.

α0: Concentration measurement value in the airtight container 2 before supply gas is mixed α1: Concentration measurement value in the airtight container 2 after supply gas is mixed ■o
:Volume inside the airtight container ■l :Amount of supplied gas mixed in■=Volume measurement of the object to be measured■ Calculation is automatically performed by the microcomputer section 6. In other words, [specific gravity (D) - weight (W) ÷ volume (
V)] to calculate the adult specific gravity. For example, if the weight (W) is 60 kg, the volume (V) is 55.8871'
(A' is 10000 m3), then the specific gravity (D) is 1.
It is calculated as 0736.

The results are displayed on the display device 13.

Perform measurement using the above steps. The flow of the supply gas is as shown in the block diagram of FIG.

As the gas concentration analysis system, gas chromatography, mass filter type gas analyzer, infrared analyzer, ceramic oxygen meter such as zirconia, etc. can be used.

Next, the present invention will be explained in detail.

Application Example 1 (Method for Calculating Average Body Fat Level) The average body fat level can be calculated as shown in Table 1 from the specific gravity of the human body determined by the hydrometer of this example and the Keith (Kc7s) formula % formula % .

Calculations such as those shown in Table 1 can also be automatically performed by the microcomputer section 6.

As a result, to take the example of adult males, those with an average body fat level of 0.10 or less have extremely low body fat;
A person with a score of around 15 is considered average, and a person with a score of over 0.20 is considered obese.

Application Example 2 (Method for Calculating Visceral Body Fat Percentage) In health checkups, medical checkups, etc., visceral fat percentage (visceral fat percentage) may become an issue. In other words, even if there is no abnormality in the average body fat percentage, if the visceral fat percentage is high, it may indicate a disease (
This is because they may be more susceptible to adult diseases such as arteriosclerosis and heart disease, and may not be considered healthy.

Therefore, the skin fat thickness (subcutaneous fat) of the human body is measured, the average body fat percentage (B) is estimated, and the magnitude of the visceral fat percentage is determined by comparing it with the average body fat percentage (A) obtained in Application Example 1. be able to.

For example, use an Eiken-style sebum thickness meter to measure at least two places, for example, the middle part of the upper arm extension side and the lower end of the scapula, and calculate the total value (S) of the following precious wood Nagamine. The specific gravity (Ds) is calculated using the following Keith's formula (
Keys' formula) to find the average body fat percentage (B).

Average body fat percentage (B) = f(4,201/Ds)
-3,8131 If so, it means you have a lot of visceral fat.

Note that an ultrasonic diagnostic device or the like may be used instead of the subcutaneous fat measuring means.

[Effects of the Invention] As explained above, according to the present invention, there is provided a means for measuring the weight of an object to be measured (for example, a human body), and a means for measuring the weight of an object to be measured (for example, a human body); A certain amount of gas is supplied or generated in an airtight container, and the gas is of a different type from the gas that initially exists uniformly within the object to be measured, and is inert, and then the concentration of the supplied gas is adjusted. , so weight and volume can be measured accurately. That is, the volume can be measured without inhibiting the respiratory function, and the volume can be measured with high accuracy without the need to measure the residual capacity of the lungs. Thereby, the volume (V) for calculating the specific gravity can be determined.

Furthermore, as an application example, average body fat percentage and visceral fat percentage can also be quickly determined.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a hydrometer which is an embodiment of the present invention,
Figures 2 (a) and (b) are conceptual diagrams of the model of the gas flowmeter;
FIG. 3 is a block diagram of the supply gas. DESCRIPTION OF SYMBOLS 1...Volume measuring device by gas analysis, 2...Airtight container, 3...Gas concentration analyzer, 4...Gas supply means, 5...Measuring means of supply gas, 6...Micro Computer section, 7...Common power supply, 8...Measurement start switch, 9...Solenoid valve, 10...Rotary valve, 11...Measuring tube, 12...Fan, 13...
-Display display device, 14... weight scale. 1...Volume measuring device by gas analysis 2...Airtight container 3...Gas concentration analyzer 6...Microcomputer section 7...Common power supply 8...Measurement start switch 9...Solenoid valve 12...Fan 13...Display display device 14...Weight scale

Claims (1)

[Claims] (1) A means for measuring the weight of an object to be measured, an airtight container in which the object to be measured is placed, a means for supplying gas into the airtight container, and a gas concentration for analyzing the gas concentration in the airtight container. A certain amount of gas, which is a different type of gas from the gas existing in the airtight container and is inert to the object to be measured, is introduced into an airtight container equipped with an analysis means and in which the object to be measured is placed. A hydrometer characterized in that the gas concentration in the airtight container is analyzed.