JPH08194050A - Supersonic wave distance measuring device using wave transmission bar - Google Patents

Abstract

PURPOSE: To measure a distance of an object to be measured in a high temperature atmosphere, to extend a range of measuring distance of the object to be measured and to improve detection performance of the object to be measured in the high temperature atmosphere. CONSTITUTION: This device is constituted of a transmission probe 1 to transmit a signal by way of carrying out electro-acoustic transduction a wave transmission bar 2 for transmission installed on the transmission probe 1 through a contact medium and to propagate a supersonic wave, a wave transmission bar 5 for reception to propagate a supersonic wave pulse reflected on a surface of an object 4 to be measured, a receiving probe 6 installed on the wave transmission bar 5 for reception through a contact medium and to receive a supersonic wave signal by way of carrying out electro-acoustic transduction and a supersonic wave distance measuring part 7 to measure a distance from reciprocal propagating time in which a supersonic wave is emitted from the transmission probe 1 and returned to the receiving probe 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic distance measuring device, and more particularly to an ultrasonic distance measuring device suitable for measuring the distance of an object to be measured in a high temperature atmosphere.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open No. 62-280649 discloses a probe used for a high temperature flaw-detecting object. The present invention relates to a probe of an ultrasonic flaw detector, in which a transducer sandwiched between electrode parts is laminated on a protective plate or a metal material directly attached to an object to be inspected, with the protective plate or the metal material. The aluminum-based heat-resistant electrode layer is integrally formed between the electrode and the vibrator, and the electrode portion of the vibrator is integrally formed. In the case of this kind, the bonding agent may be peeled off due to the thermal expansion of the protective plate in an atmosphere reaching a very high temperature such as in a molten metal.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to expose a portion of a waveguide rod to a high temperature atmosphere so that the probe is not directly exposed to the high temperature atmosphere. An object of the present invention is to provide an ultrasonic distance measuring device capable of measuring the distance of an object to be measured in a high temperature atmosphere by mounting it on the upper surface of a waveguide rod that is not exposed to the inside.

A second object of the present invention is to provide an ultrasonic distance measuring device capable of expanding the ultrasonic distance measuring range.

[0005]

In order to achieve the above-mentioned object, the present invention provides a transmitting probe for performing electroacoustic conversion and transmitting a signal, and an ultrasonic wave attached to the transmitting probe via a contact medium. A propagating transmitting waveguide rod, a receiving waveguide rod that propagates the ultrasonic pulse reflected on the surface of the object to be measured, and a receiving waveguide rod and a contact medium that are mounted via a couplant to perform electroacoustic conversion. It is composed of a receiving probe that receives a sound wave signal and an ultrasonic distance measuring unit that measures the distance from the round-trip propagation time until the transmitting probe emits ultrasonic waves and returns to the receiving probe. In order to achieve the second object, according to the present invention, a transmitting probe that performs electroacoustic conversion and transmits a signal, an ultrasonic wave that is attached via the transmitting probe and a couplant, propagates ultrasonic waves, and a radiating surface is a slope. A transmission waveguide rod having a shape, and a reception waveguide rod that propagates the ultrasonic pulse reflected on the surface of the measured object,
The receiving probe, which is attached to the receiving waveguide rod through the contact medium, performs electroacoustic conversion and receives ultrasonic signals, and the ultrasonic wave is reflected from the transmitting probe and returns to the receiving probe. An ultrasonic distance measuring unit that measures the distance from the round-trip propagation time, a gear formed on the circumference of the transmitting waveguide rod, and a transmission waveguide rod that meshes with the gear and is placed on the center axis of the transmitting waveguide rod. A motor for rotating the waveguide rod to be rotated, an encoder for detecting the rotation angle of the waveguide rod for transmission, a signal from the encoder is calculated to calculate the current angle of the waveguide rod, and a control signal is sent to the motor for rotating the waveguide rod. It is composed of an integrated control device that outputs

The second object is also achieved by making the emitting surface of the transmitting waveguide rod convex.

[0007]

[Function] A part of the waveguide is exposed to a high temperature atmosphere so as not to expose the probe directly to the high temperature atmosphere, and the probe is mounted on the upper surface of the waveguide not exposed to the high temperature atmosphere. . When measuring the distance to the object to be measured, an ultrasonic wave signal is transmitted by the transmitting probe, and the ultrasonic wave propagates in the transmitting waveguide rod attached via the transmitting probe and the contact medium. The ultrasonic pulse reflected by the surface of the measured object is received by the receiving waveguide rod, propagates in the waveguide rod, and is transmitted by the receiving probe attached via the receiving waveguide rod and the contact medium. The signal is received. The distance can be measured from the round-trip propagation time until the ultrasonic wave is radiated from the transmitting probe by the ultrasonic distance measuring unit and returns to the receiving probe.

In the second method, the encoder detects the rotation angle of the transmitting waveguide rod, the signal from the encoder is taken in, and the current angle of the waveguide rod is calculated. As a result, the waveguide rod rotating motor is obtained. A control signal is output to and the transmission waveguide rod is rotated on the central axis by the waveguide rod rotation motor. Since the emitting surface of the transmitting waveguide is a sloped surface, ultrasonic waves are refracted,
By rotating the transmitting waveguide rod, the ultrasonic distance measurement range can be expanded.

Further, in the third method, the emission angle of ultrasonic waves is expanded by the convex emission surface of the transmitting waveguide rod.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows one embodiment of the present invention and shows the entire structure.

The transmitting probe 1 for transmitting ultrasonic signals and the transmitting waveguide rod 2 for propagating ultrasonic waves are attached via a contact medium. Similarly, the receiving probe 6 and the receiving waveguide rod 5 are attached via a contact medium. The transmitting waveguide rod 2 and the receiving waveguide rod 5 are fixed at regular intervals by cooling fins 8. A part of the transmission waveguide rod 2 and the reception waveguide rod 5 is exposed to the ultrasonic wave propagation medium 3 in a high temperature atmosphere such as a molten metal. The transmitting probe 1 and the receiving probe 6 are attached to the upper surface of the waveguide rod that is not exposed to the high temperature atmosphere. The emitting surface of the transmitting waveguide rod 2 has a convex shape. Ultrasonic waves are radiated from the transmitting probe 1, are reflected on the surface of the measured object 4, and measure the distance from the round-trip propagation time until they return to the receiving probe 6 via the receiving waveguide rod 5. The ultrasonic distance measuring unit 7 is installed outside.

FIG. 2 shows the relationship between the shape of the emitting surface of the transmitting waveguide rod 2 and the spread of ultrasonic waves. The transmitting probe and the receiving probe were 1 MHz, the distance between the emitting surface of the transmitting waveguide rod 2 and the receiving probe was 700 mm, and the ultrasonic wave distribution was measured.
The horizontal axis represents the ultrasonic wave spread (mm) and the vertical axis represents the ultrasonic wave reception intensity (dB). In the figure, the solid line shows the flat emission surface, the broken line shows the taper shape, and the alternate long and short dash line shows the spherical shape.
From this, it can be seen that the ultrasonic waves spread when the radiation surface has a convex shape, that is, a tapered shape or a spherical shape.

The distance measurement of ultrasonic waves will be described with reference to FIG. In the distance measurement using ultrasonic waves, what is called the ultrasonic wave propagation medium 3 from the transmission probe 1 which transmits an ultrasonic wave signal, through the transmission wave guide rod 2, the ultrasonic wave propagation medium 3 such as a high temperature liquid metal, etc. Until the ultrasonic pulse is emitted to the surface of the measured object 4 having different acoustic impedance, the ultrasonic pulse is reflected on the same surface, and returns to the receiving probe 6 via the receiving waveguide rod 5. The round-trip propagation time T is measured, and the value is calculated by subtracting the propagation time t of the transmission waveguide rod 2 and the reception waveguide rod 5 which are ultrasonic propagation media from the value of T and the sound velocity v of the high temperature liquid metal. The distance L between the tip of the rod and the ultrasonic reflection surface of the measured object 4 is measured according to the equation (1).

[0015]

L = (T−t) · v / 2 (Equation 1) In the block diagram of FIG. 3, 1 is a transmission probe that performs electroacoustic conversion and transmits an ultrasonic signal, and 2 is a transmission conductor. Wavy stick, 3
Is an ultrasonic wave propagation medium such as a high temperature liquid metal, 4 is an object to be measured having an acoustic impedance different from that of the ultrasonic wave propagation medium 3, 5 is a receiving waveguide rod, and 6 is electroacoustic conversion to receive an ultrasonic wave signal. A reception probe, 70 is a transmitter that gives a transmission signal to the transmission probe 1, 71 is a receiver that amplifies the reflected pulse received by the reception probe 6, and 72 is preset for pulse transit time measurement. An amplitude comparison circuit that compares the amplitudes of the reflected threshold level and the reflected pulse, 73
Is a stop pulse generation circuit that generates a signal that stops the counting of the reference pulse generated by the reference pulse generation circuit 76 in synchronization with the output of the amplitude comparison circuit 72, and 74 starts the transmission pulse and starts the counting of the reference pulse. A start pulse generation circuit for generating a signal, a gate circuit 75 for setting a period for counting the reference pulse number by a start pulse and a stop pulse, 77 for a counter for counting the reference pulse number within the period in which the gate is opened, and 78 for An arithmetic circuit for obtaining the ultrasonic pulse propagation time T from the output of the counter 77 and further calculating the distance L according to the equation 1 is a display for displaying the distance L calculated by the arithmetic circuit 78.

FIG. 4 shows another embodiment of the present invention.

FIG. 4 shows the transmission waveguide rod 2 of the embodiment shown in FIG. 1 to which a rotation function is added. The emitting surface of the transmitting waveguide rod 2 has a sloped shape. Since the emitting surface has a sloped shape, ultrasonic waves are refracted and emitted in an oblique direction as shown in FIG. The gear 10 is formed on the circumference of the transmitting waveguide rod 2, and meshes with the gear 11 to form a waveguide rod rotating motor 12 that rotates the transmitting waveguide rod 2 on the central axis of the transmitting waveguide rod 2. It is connected. The encoder 13 detects the rotation angle of the transmitting waveguide rod 2. In the integrated controller 9, the waveguide rod current angle calculation unit 91 takes in a signal from the encoder 13 to calculate the current angle of the waveguide rod, and the waveguide rod rotation mechanism control unit 92 controls the waveguide rod rotation motor 12. Output a signal.

FIG. 5 shows a detection method when the position of the measured object 4 is different. The integrated control device 9 outputs a control signal to the waveguide rod rotation motor 12 to rotate the transmission waveguide rod 2 so that the measured object 4 can be detected.

By rotating the transmitting waveguide rod 2 as shown in FIGS. 4 and 5, the distance measuring range of the object 4 to be measured can be expanded.

[0020]

According to the present invention, directly in a high temperature atmosphere,
In order to avoid exposing the probe, part of the waveguide is exposed to a high temperature atmosphere, and the probe is mounted on the upper surface of the waveguide that is not exposed to the high temperature atmosphere. Since the distance of the object can be measured and the distance measurement range of the object to be measured can be expanded, the detection performance of the object to be measured in a high temperature atmosphere is improved.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of an embodiment of the present invention.

FIG. 2 is a characteristic diagram of the shape of the emitting surface of the transmitting waveguide rod and the spread of ultrasonic waves.

FIG. 3 is an explanatory view of ultrasonic distance measurement.

FIG. 4 is an explanatory view showing another embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a detection method when the position of the measured object is different.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transmitting probe, 2 ... Transmitting waveguide rod, 3 ... Ultrasonic propagation medium, 4 ... Object to be measured, 5 ... Receiving waveguide rod, 6 ... Receiving probe, 7 ... Ultrasonic distance measuring unit .

Claims (3)

[Claims] 1. A transmission probe that performs electroacoustic conversion and transmits a signal, a transmission waveguide rod that is attached to the transmission probe through a contact medium and propagates ultrasonic waves, and a surface of an object to be measured. A receiving waveguide that propagates the ultrasonic pulse reflected by
A reception probe attached to the reception waveguide rod through the contact medium to receive an ultrasonic signal by performing electroacoustic conversion, and an ultrasonic wave emitted from the transmission probe and returned to the reception probe. An ultrasonic distance measuring device using a waveguide rod, comprising: an ultrasonic distance measuring unit that measures a distance from a round-trip propagation time until arrival. 2. A transmission probe that performs electroacoustic conversion and transmits a signal, and a transmission waveguide that is attached to the transmission probe via a couplant to propagate ultrasonic waves and has a radiating surface having a slope shape. The rod, the receiving waveguide rod that propagates the ultrasonic pulse reflected by the surface of the object to be measured, and the receiving waveguide rod are attached via a contact medium, and electroacoustic conversion is performed to receive an ultrasonic signal. A receiving probe, an ultrasonic distance measuring unit that measures a distance from a round-trip propagation time until ultrasonic waves are emitted from the transmitting probe and return to the receiving probe, and the transmitting waveguide rod A gear formed on the circumference of, a motor for rotating the waveguide rod that meshes with the gear to rotate the waveguide waveguide for transmission around the central axis of the waveguide waveguide for transmission, and a waveguide rod for transmission. An encoder that detects a rotation angle and a waveguide rod that receives a signal from the encoder Currently it calculates the angle, the waveguide rod and outputs a control signal to the rotation motor integrated control unit and that the ultrasonic distance measuring device using a waveguide rod, characterized in consisting of. 3. The ultrasonic distance measuring device according to claim 1, wherein the transmitting waveguide rod has a convex radiation surface.