JPS58131556A - Detector for characteristic of liquid - Google Patents

Abstract

PURPOSE:To detect the viscosity of a liquid to be measured, the presence of bubbles in the liquid, the mixture of foreign substances, etc. by penetrating an elastic or flexible pipe for leading the liquid into a case filled with the liquid and fitting sound wave transmitting and receiving end microphones to the wall of the case so as to hold the pipe between them. CONSTITUTION:A detection box 1 is filled with a liquid, the flexible or elastic pipe 13 is penetrated and fixed into/on the case 1 and the sound wave transmitting and receiving end microphones 2, 3 are opposed so as to hold the pipe 13 between them. The liquid to be measured is sent from a system 6 to be measured through the pipe 13 and an intermittent pulse wave generated by an intermittent pulse generating circuit 4 is converted into a sound wave by the transmitting end microphone 2. After passed through the detection box 1, the sound wave is received by the receiving end microphone 3, converted into an electric signal by an AM demodulating circuit 51 and then converted into a digital signal by an AD converting circuit 52. The digital waveform is compared with data to be changed in accordance with the characteristics of the liquid to be measured which have been previously measured by a waveform analysing circuit 53 and the compared result is displayed on a displaying circuit 54.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for detecting properties of a liquid using acoustic waves or ultrasonic waves.

The purpose of the present invention is to detect liquid characteristics that can continuously and easily detect the viscosity of the liquid to be measured, the presence or absence of air bubbles in the liquid, the presence of foreign substances, the position of the interface between the liquid flowing in the pipe and the gas, etc. The purpose is to provide equipment.

Next, the present invention will be explained based on embodiments shown in the drawings.

1 is a rectangular parallelepiped-shaped container 11 in which a liquid is sealed, and a flexible or pliable pipe 13 is passed through the container 11 and fixed.Detection boxes 2 and 3 are the container 1 of the detection box.
Reference numeral 1 indicates an ultrasonic transmitting end microphone and an ultrasonic receiving end microphone that are firmly fixed to face each other so as to sandwich the pipe 13; 4, a pulse generating circuit 5 that generates intermittent pulses from the transmitting end microphone 2; This is a waveform analysis circuit for sound waves.

As shown in FIG.
3 is connected to the system to be measured, and as shown in FIG. The receiving end microphone 3 receives the wave, the AM (amplitude modulation method) Ha11 circuit 51 converts the received wave into an electrical signal, the A-D conversion circuit 52 converts it into a digital signal, and this digital waveform is converted into a waveform using a microcomputer. The analysis circuit 53 compares this with data that has been measured in advance and changes depending on the characteristics of the fluid to be measured, and the display circuit 54 displays the data.

When the intermittent pulse a is generated by the pulse generation circuit 4, it is attenuated in the detection box 1 as the viscosity of the liquid to be measured flowing through the pipe 13 increases, and the waveform outputted by the AM demodulation circuit 52 is as shown in FIG. As shown in A to F, the waveforms change as shown in b to Q in response to an increase in viscosity. Therefore, the output waveform of this AM demodulation circuit is previously measured in detail for each liquid to be measured and stored in the waveform analysis circuit 53.
The data is compared with the output data of the A-D conversion circuit 52 during measurement and displayed on the display circuit 54. Fig. 5 h~ shows the output waveform of the A-M demodulation circuit 51 when metal powder is mixed into the liquid to be measured and the amount of the mixed metal powder is increased, and 1 in Fig. 6 shows the output waveforms of the A-M demodulation circuit 51. A when there are bubbles 15 in the liquid to be measured and the bubbles 15 are located between the sending end microphone 2 and the receiving end microphone 3.
-M shows the output waveform of the demodulation circuit 51, and m shows the output waveform when there is no bubble 15.

FIG. 7n-r shows the relationship between the positions N to R of the boundary surface of the liquid to be measured flowing through the pipe 13 and the output waveform of the A-M demodulation circuit 51 when the boundary surface is at the position.

FIG. 8 shows a liquid characteristic detection device in which the system to be measured has a flexible or flexible pipe 17 through which the liquid to be measured flows. In this case, the container 1 is divided into two parts so that the pipe 17 can be inserted between them, and the characteristics of the liquid to be measured can be measured by inserting the pipe 17 and filling the inside with liquid.

FIG. 9 shows a continuous detection device that includes a pulse generation circuit and a waveform analysis circuit and is capable of continuously detecting the characteristics of a fluid to be measured in a constant cycle.

Transmitter 8 The microcomputer waveform analysis circuit 81 outputs an oscillation start signal from the P1 port to the oscillation control circuit 82 in order to oscillate ultrasonic waves in the measurement system.

The oscillation control circuit 82 inputs the oscillation start signal output from the waveform analysis circuit 81 such as a microcomputer, inputs the number of pulses to be output to the sending end microphone from the pulse number setting circuit 83, and sets the oscillator 84 to the "low" level. After confirming that this is the case, a "high" level signal is output to the gate circuit 85.Then, the number of pulses from the oscillator 84 is counted, and when it reaches the number of pulses input from the pulse number setting circuit 83, The ``high'' level signal that was being output to the gate circuit is changed to ``low'' level.

The pulse number setting circuit 83 outputs a predetermined number of pulses to the constant oscillation control circuit 82 during measurement.

The oscillator constantly outputs pulses at the oscillation frequency of the sending end microphone 86 to the oscillation control circuit 82 and the gate circuit 85.

The gate circuit 85 outputs the pulse from the oscillator 84 to the amplifier circuit 86 while the signal output from the oscillation control circuit 82 is at the "hyper level", and when the signal is at the "low level", the gate circuit 85 outputs the pulse to the amplifier circuit 86 at the "low" level. Constantly outputs the level.

The amplifier circuit 86 amplifies the power of the signal output from the gate circuit 85 and outputs the amplified signal to the sending end microphone 2 .

In this way, a predetermined number of pulses is output to the sending end microphone 2, and ultrasonic waves are oscillated in the measurement system.

Note that from the oscillation control circuit 82 to the gate circuit 85
(oscillation control circuit 82, pulse number setting circuit 8
3. The operation of the oscillator 84 and gate circuit 85) can also be performed by a program of a waveform analysis device [81] such as a microcomputer.

Receiving section 9 The amplifier circuit 91 linearly amplifies the signal output from the receiving end microphone 3 and outputs it to the detection circuit 92.

The detection circuit and the LP filter circuit 99 manually input the signal output from the amplifier circuit, and output the AMli[modulated signal to the A-D conversion circuit 94. The A-D conversion circuit 94 converts the analog signal input from the LP filter circuit 93 into a digital signal and outputs it to the waveform analysis circuit 81 such as a microcomputer.

As described above, the liquid characteristic detection device of the present invention uses a flexible pie circuit for guiding the liquid to be measured.

a container through which the pipe passes and is filled with liquid; a sound wave sending end microphone and a sound wave receiving end microphone fixed to the wall of the container so as to sandwich the pipe; and activating the sending end microphone. It consists of a pulse generation circuit and a waveform analysis circuit for the waveform received by the receiving end microphone, so it can check the viscosity of the liquid to be measured, the presence or absence of air bubbles in the liquid, the presence of foreign matter, and the interface between the liquid and gas flowing in the pipe. The characteristics of the fluid to be measured can be easily detected continuously.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the liquid characteristic detection device of the present invention, FIG. 2 is an explanatory diagram of its use, FIG. 3 is a block diagram of the liquid characteristic detection device, FIGS. 4, 5, 6, Figure 1 is a waveform diagram after AM recovery w4 detected according to the characteristics of the liquid to be measured.
The figure shows another usage explanatory diagram, and FIG. 9 shows a block diagram of the continuous detection device. In the diagram: 1...Detection box, 2...Microphone at sending end, 3...
Receiving end microphone, 4... Intermittent pulse generation circuit, 5... Waveform analysis 7i71 diagram, 1 0 72 diagram 73 diagram) 7I78 diagram 4 (5)

Claims (1)

[Claims] 1) A flexible or flexible pipe for guiding the liquid to be measured, a container through which the pipe penetrates and is filled with liquid, and a sound wave transmitter fixed to the wall of the container so as to sandwich the pipe. A liquid characteristic detection device comprising an end microphone, a sound wave receiving end microphone, a pulse generation circuit for operating the sending end microphone, and a waveform analysis circuit for a waveform received at the receiving end microphone.