JPH01118722A - Volume measuring instrument - Google Patents

Abstract

PURPOSE:To take a measurement accurately and easily by providing a resonator whose port is connected to a closed box and an oscillator which makes the resonator resonate while a body to be detected is stored in the closed box, and performing the measurement by using the resonance frequency of the oscillator as information. CONSTITUTION:The shutter 7 of an oscillation chamber 4 is closed, the oscillator 3 is oscillated while the frequency is varied almost at the characteristic resonance frequency fr of the resonator 8 and in a larger range, and it is confirmed that the oscillation chamber 14 does not resonate. Then the closed box 2 (linked with the oscillation chamber 4 by a cylindrical port 5) is emptied and the shutter 7 is opened; and the oscillator 3 is oscillated to make the resonator 8 resonate, and calibration is so performed that the frequency is fr. Then a living cow 9 is put in the closed box 2, the resonator 8 is made to resonate, and the current resonance frequency fr' is read. The volume V' of the air in the closed box 2 excluding the cow 9 is found from the relation between the volume V of the air in the closed box 2 regarding the Helmholtz resonator 8 according to said values, and the volume of the cow 9 is measured from the volume V-V'.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a volume measuring device, and more particularly to a volume measuring device that can perform simple measurements by using a holm-hertz resonator.

(Prior art) For example, in order to judge the quality of a cow's meat as meat at a slaughterhouse, it is necessary to estimate the amount of fat in a living body that is used as meat. Information becomes essential.

Conventionally, the volume of a cow is estimated by measuring the body weight and using past statistical data based on this body weight, but this method has large errors due to variations in the body shape of the cow. It is difficult to measure the volume accurately.

(Problem to be solved by the invention) Therefore, when accuracy is particularly required, a cow is placed in a water tank with grooves, the water is removed, and the amount of water remaining in the tank is measured. Volume measurement is thus performed.

However, measuring each animal using this method is not only extremely troublesome and time-consuming, but also makes it difficult to carry out the process smoothly as the body is afraid of water.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a volume measuring device that can accurately and easily measure the volume of a subject.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a resonator in which a port is connected to a sealed box, and an oscillation device that causes the resonator to resonate when a subject is accommodated in the sealed box. The method is characterized in that the volume of the subject is measured using the resonant frequency of the oscillating body as information.

(Function) In this invention, the oscillator is vibrated with the subject housed in the sealed box to cause the resonator to resonate, and based on the resonance frequency at this time, the gas in the sealed box related to the Form Hertz resonator is The volume of the subject can be measured by determining the volume of the gas inside the sealed box excluding the subject from the relationship between the volume and the resonance frequency, and subtracting this value from the volume of the sealed box.

(Example) Next, an example of the present invention will be described in detail with reference to the accompanying drawings.

Reference numeral 1 in the figure is a volume measuring device, in which a sealed box 2 in which a living body, for example, as a subject is housed, and an oscillation chamber 4 in which a frequency-changeable oscillator 3 is housed are connected through a cylindrical port 5. It consists of

The oscillation chamber 4 has a sound absorber 6 pasted all over its interior, and is further provided with a shutter 7 for opening and closing the port 5.

The unique resonant frequency fr (7 seconds) of the resonator 8 constituted by the sealed box 2 and the port 5 is given by the following equation, which is well known as a Holm Hertz resonator.

That is, when acoustic energy is applied to the resonator 8, the energy at the resonant frequency f' is converted into thermal energy and absorbed, and is no longer reflected.

Further, if the volume of the gas in the sealed box 2 excluding the inside of the living body stored in this sealed box 2 is Vo, then the resonance frequency fr' with the inside of the living body stored in the sealed box 2 is similarly given by the following equation.

However, S: Cross-sectional area of the port (cm2) ■ = Volume of the sealed box (cm3) L: Length of the port (cm) r: Radius of the port (cm) C: Speed of sound = 34000 (cm/sec) L' = L + 1 ．．
8r (cm) π: Pi The following relational expression holds true between the volume of the cow, V (cow), and ■, Vo.

V (cow)-v-v' . . . 0 Next, a method of measuring volume in a living body using this volume measuring device 1 will be explained.

As shown in FIG. 1(a), with the shutter 7 of the oscillation chamber 4 closed, the oscillator 3 oscillates by changing the frequency around and in a larger range than the unique resonance frequency fr of the resonator 8. It was confirmed that the oscillation chamber 4 exhibited a frequency characteristic as shown in FIG. 1(b) and that the oscillation chamber 4 did not resonate. Note that the resonant frequency fr is determined by the following equation.

After that, as shown in FIG. 2(a), with the closed box 2 empty and the shutter 7 opened, the oscillator 3 is oscillated to cause the resonator 8 to resonate, and the frequency at this time is the resonant frequency f.
Calibrate so that r (Figure 2 (
b)). This caliper plane 3 is used to avoid the influence of changes in the speed of sound C due to changes in temperature and humidity.

After the calibration is completed, as shown in Fig. 3(a), the resonator 8 is made to resonate with the living body 9 housed in the sealed box 2, and the resonant frequency fr' at this time is read (Fig. 3(b) )), from this resonant frequency fr' and formula ■, the volume V
Determine °, and use the known volume of the sealed box (■) and formula (2) to determine the volume of the cow, V (cow).

In this way, by storing the living body 9 in the sealed box 2, causing the oscillator 3 to oscillate, causing the resonator 8 to resonate, and measuring the resonance frequency fr', the volume V (cow) inside the living body can be accurately and accurately determined. It can be easily measured.

Next, the specific fr value of the resonator with the internal shape shown in FIG. 4 is calculated as follows.

V = 280 (πx 702/2 + 140 x 11
0)"r 6 x 10'cm3 S=rt x 50's 7850cm"
? (SO+0.lI X l(10)-130cm
C/2 g-5,4x 103cm7 seconds-17,130
1z) Furthermore, when V (cow) = 20001, the resonance frequency fr'' is -20,'18L[134Hz, which is approximately 3.85Hz higher.

Examining the change in △fr for a 1°C change in the volume V of the sealed box, it is -20,983649Hz, and for a change in volume of 1ooOcc (・+4) or 1/2000, the change in resonance frequency is Q,G
O3)1z.

Therefore, a display resolution of 7 digits is required, and therefore the original oscillation frequency must be set to IMHz or higher.

Note that the oscillation chamber 4 is for efficiently imparting the acoustic energy from the oscillator 3 to the resonator 8, and if this is provided, it should be made larger than the sealed box 2 in order to prevent resonance of the oscillation chamber 4 itself. However, the oscillation chamber 4 is not necessarily required.

In addition, the shape of the closed box 2 in this embodiment is a semi-cylindrical shape as shown in FIG. 4 in order to eliminate wasted space when storing cows, but the shape is not limited to this. Without,
The shape of the port is also not limited to a cylinder. However, in the case of a shape other than a cylinder, it is necessary to change the value of Lo to a value corresponding to this.

Furthermore, the test subject is not limited to cows, but may also be other living livestock such as living pigs, and is not limited to living livestock; if used to measure the volume of the human body, it is expected to be useful in bioscience. can.

(Effects of the Invention) As explained above, the volume measuring device of the present invention includes a resonator whose port is connected to a sealed box, and an oscillator that causes the resonator to resonate when a subject is accommodated in the sealed box. Since the volume of the subject is measured using the resonant frequency of the oscillating body as information, the volume of the subject can be measured accurately and easily.

[Brief explanation of the drawing]

Figures 1 to 3 show a schematic diagram and a frequency characteristic diagram of the volume measuring device, Figure 1 (a) is a schematic diagram for checking the frequency characteristic of the oscillation chamber, and Figure 1 (b) is its frequency characteristic diagram. , second
Figure (a) is a schematic diagram of the calipresicon, Figure 2 (b)
3 is a diagram showing its frequency characteristics, FIG. 3 is a schematic diagram showing resonance when the cow is housed, FIG. 3(b) is a diagram showing its frequency characteristics, and FIG. 4 is a diagram showing the size of the internal space of the resonator. In the figure, 1 is a volume measuring device, 2 is a sealed box, 3 is an oscillator,
5 is a port, 8 is a resonator, and 9 is inside the living body. Patent applicant Seiko System Giken Co., Ltd. (a) (b) Figure 1 (a) (b) Figure 2 (a) Figure 3 Figure 4

Claims (2)

[Claims] (1) A resonator that connects a port to a sealed box, and an oscillator that causes the resonator to resonate when a subject is housed in the sealed box, and uses the resonant frequency of the oscillator as information to generate the sound of the subject. A volume measuring device that measures volume. (2) The volume measuring device according to claim 1, wherein the subject is a living domestic animal or a human body.