JPS61105429A - Measuring device for intensity of ultrasonic output - Google Patents

Abstract

PURPOSE:To improve measurement precision, and to eliminate the need for a balance readjustment of a balance and to improve the operation efficiency by providing an oily liquid layer which has less specific gravity than the liquid in a container over the surface of the liquid in the container, and preventing the liquid in the container from vaporizing. CONSTITUTION:A pressure receiving plate 10 which absorbs or reflects greatly an ultrasonic wave is suspended with a suspension wire 11 from a hook 7 at the opposite side of a weight on the balance 3 and dipped in the liquid 2. The oily liquid 16 which has less specific gravity and the less quantity of vaporization than the liquid 2 is provided over the surface of the liquid 2 in the container 1. This oily liquid 16 is layered preferably to an about 2-5mm thickness. Thus, the surface of the liquid 2 is covered with the oily liquid 16, so the vaporization of the liquid 2 is prevented and the quantity of vaporization of the oil liquid 16 is small, so liquid drops are prevented from sticking on the suspension wire 11, hook 7 of the balance, or the whole of balance 7 and weight variation is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to the field of industrial application.
The present invention relates to an ultrasonic output intensity measuring device for measuring ultrasonic output intensity.

Structure of conventional examples and their problems In recent years, the advantages and disadvantages of ultrasound diagnostic methods have become important in various fields of medicine, and along with this, the prevalence of ultrasound diagnostic equipment has also increased. 0One of the reasons)L
& Compared to diagnostic equipment, it is safer and easier to use.

Under these circumstances, research has recently been conducted on the effects of ultrasound on the human body, and related to this research, devices for measuring the intensity of ultrasound output have been developed.

Currently, the measurement of ultrasonic output intensity is basically divided into four types: (1) mechanical method, @) electrical method, (3) caloric method, and (4) optical method. Among them, the measurement method using a balance, which is one of the mechanical methods, is capable of determining the an+ constant of ultrasonic output as low as several tens of μW to several + mW, and it is relatively easy to determine the absolute output from weight changes. Because of its ability to perform ultrasonic wave output intensity measurement in the field of ultrasonic diagnostic equipment, it has become very popular.

In a conventional ultrasonic output intensity measuring device using a balance, a liquid 2 such as water is contained in a container 1, as shown in FIG. On the other hand, the balance 3 has a rod-shaped body 4 whose central part is supported by a fulcrum 6, and is provided with 7 hooks 6°7 on both sides.A plate 8 is suspended from the hook 6 on the minus side, and a weight 9 is listed. A pressure receiving plate 10 is suspended by a hanging line 11 from a hook 7 on the opposite side of the weight 9 in this balance 3, and this pressure receiving plate 1
0 is submerged in the liquid 2 in the container 1. balance 3
A weight measuring amplifier 12 and a recorder 13 are successively connected to the fulcrum 5 as measuring means.

Then, the ultrasonic probe 16 also emits ultrasonic waves in response to a drive signal applied from the ultrasonic diagnostic device 14, and these ultrasonic waves are applied to the pressure receiving plate 1o through the transparent portion 1a at the lower part of the container 1. Incidentally, the radiation pressure caused by ultrasound is the Rayleigh radiation pressure and the Langevin radiation pressure τ', and the radiation pressure that appears under normal usage conditions of the ultrasonic diagnostic apparatus is the latter Langevin radiation pressure.

This radiation pressure F is equal to the ultrasonic energy density E on the pressure receiving plate 10@q surface that receives the radiation pressure, and the ultrasonic output intensity W is finally expressed by the following formula: OW=F −C=
6m -gn-niko, 6m is the weight change detected by the balance 3 connected to the pressure receiving plate with the hanging wire 11, gn is the standard gravitational acceleration, and C is the container 1.
This is the sound velocity of the liquid 2 contained in the liquid 2. Conventionally, deaerated water is used as the liquid 2. Therefore, the intensity of the ultrasonic output from the ultrasonic probe 15 received by the pressure receiving plate 1o can be determined by measuring the change in weight using the balance 3. That is, the change in the amount of the vehicle is amplified by the weight measurement amplifier 12 and recorded in the recorder 13.]The weight 9 balances the ik amount of the pressure plate 10 with the ultrasonic wave before irradiating the pressure plate 1o with the ultrasonic wave. It is meant to be taken.

However, although C, the weight change treated as a balance 3 is, for example, 11
When trying to measure the ultrasonic output intensity of nw, using water as the liquid 2 in the container 1 and measuring at a water temperature of 20°C, the weight change Δm is 66.8 μq, which is a very small value. The issue of measurement conditions is important. Conventionally, water is used as the liquid 2 in the container 1 of the ultrasonic output intensity measuring device using this balance, as described above, so the water evaporates during measurement, and the water droplets are transferred to the balance 3. There were problems such as the weight gradually changing, the measurement accuracy being poor, the balance of the balance 3 having to be readjusted, and the work efficiency being poor.

OBJECTS OF THE INVENTION An object of the present invention is to provide an ultrasonic output intensity measuring device that improves the accuracy of measurement, eliminates the need to readjust the balance of the balance, and improves work efficiency. It is something.

Structure of the Invention In order to achieve the above-mentioned object, the present invention includes a container containing a liquid, a measuring means for measuring the weight change obtained from the opposite side of the balance from the weight, and the above-mentioned. The container is characterized by comprising an oily liquid layer contained on the surface of the liquid in the container and having a specific gravity lower than that of the liquid, and this liquid layer is configured to prevent the liquid in the container from evaporating. .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 2, a liquid 2 such as water is contained in a container 1. The hook 7 of the balance 3 absorbs the ultrasonic waves described later,
Alternatively, a pressure receiving plate 1o for reflection is suspended from a suspension line 11, and this pressure receiving plate 10 is submerged in the liquid 2. On the surface of the liquid 2 in the container 1, an oily liquid 16 having a lower specific gravity and a smaller amount of evaporation than the liquid 2 is stored. As this oil-based liquid 16, it is preferable to use silicone oil (such as polydimethylsiloxane) with a specific gravity (1) and a low viscosity, and to form a layer with a thickness of about 2 to 6 mm.Other configurations are conventional. It is similar to that shown in FIG.

According to the apparatus of the above embodiment, since the surface of the liquid 20 is covered with the oily liquid 16, evaporation from the liquid 2 is prevented.Of course, since the amount of evaporation of the oily liquid 16 is small, the hanging wire 11. It is possible to prevent droplets from adhering to the hook 7 of the balance 3 or the entire balance 3.

Effects of the Invention As is clear from the above explanation, according to the present invention, a pressure receiving plate is suspended in a liquid in a container from the side opposite to the weight of a balance, and the ultrasonic wave to be measured is irradiated to this pressure receiving plate, The weight change due to irradiation here is measured using the balance, and at this time, by providing an oily liquid layer on the surface of the liquid in the container, which has a lower specific gravity and a smaller amount of evaporation than the liquid,
It is possible to prevent droplets from adhering to the balance due to evaporation of the liquid in the container, and to suppress weight changes. Therefore, it is possible to improve the measurement angle by 8 degrees, and it is not necessary to readjust the balance of the balance, which has the advantage of improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of a conventional ultrasonic output intensity measuring device, and FIG. 2 is a partially cutaway front view of essential parts showing an embodiment of the ultrasonic output intensity measuring device of the present invention. 1...container, 2...liquid, 3...
・Balance, 1o...Pressure plate, 11...Hanging wire, 12...Weight measurement amplifier, 13...
Recorder, 14... Ultrasonic diagnostic device, 15...
...Ultrasonic probe, 16... Oil-based liquid.

Claims (1)

[Claims] A container containing a liquid, a pressure receiving plate suspended from the opposite side of the balance in the liquid in the container and irradiated with ultrasonic waves to be measured, and irradiating the pressure receiving plate with ultrasonic waves. An ultrasonic output intensity measuring device comprising: a measuring means for measuring the weight change obtained by using the balance; and an oily liquid layer that is housed on the surface of the liquid in the container and has a specific gravity smaller than that of the liquid. .