JP2922348B2 - Surface wave sound velocity measuring instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface acoustic wave velocity measuring instrument for previously obtaining a surface acoustic wave propagation velocity when measuring the outer circumference of a device having a circular cross section using a surface acoustic wave. It is about.

[0002]

2. Description of the Related Art FIG. 4 is a view showing a conventional surface acoustic wave velocity measuring instrument . In the drawing, reference numeral 1 denotes an object to be measured, 2 denotes a belt having flexibility along the surface of the object 1 to be measured, and 3 denotes this belt. 2 is a bracket for fixing one end, 4 is a magnet holder for fixing the bracket 3, 5 is a reflector attached to the bracket 3, 6 is a probe housing for fixing the other end of the belt 2, and 7 is this probe. A surface acoustic wave probe housed and fixed in the housing 6, 8 is a contact rubber disposed between the surface acoustic wave probe 7 and the device under test 1, 9 is a contact rubber that holds the contact rubber 8 and is attached to the probe housing 6. Shu.

The conventional surface acoustic wave velocity measuring device is constructed as described above. To measure the outer circumference of the DUT 1, the belt 2 is positioned along the circumferential direction, and the magnet holder 4 is positioned.
Is fixed on the surface of the DUT 1. At this time, the bracket 3 fixed to the magnet holder 4 is parallel to the axial direction of the DUT 1, and at the same time, the reflection plate 5 is also in contact with the surface of the DUT 1 in parallel with the axial direction. Since the belt 2 is already in the circumferential direction, its flexibility is used to properly contact the surface of the DUT 1 so as to cover the shoe 9 attached to the probe housing 6 at the other end of the belt 2. When pressed against the workpiece 1, the contact rubber 8 follows the surface of the workpiece 1 while being compressed, and the probe housing 6
And the surface wave probe 7 is correctly positioned. The surface wave transmitted to the DUT 1 via the surface wave probe 7 and the contact rubber 8 has a reflection source on the surface of the DUT.
In some cases, the object to be measured 1
The light propagates on the circumferential surface along the belt 2, and is reflected by the reflector 5 which keeps a predetermined distance by the belt 2 , follows the reverse path, and enters the surface acoustic wave probe 7 again. Therefore, by measuring the time T during this time and calculating L / T from the distance L between the surface wave probe 7 and the reflecting plate 5, the sound velocity V of the surface wave becomes known, and the time T 'of the surface wave making one round is further determined. By measuring, the outer circumference of the DUT 1 can be measured by T ′ × V. The measurement of the times T and T 'is based on the assumption that the propagation time in the contact rubber 8 and the surface acoustic wave probe 7 has been subtracted in advance, and the measurement of the object 1
The propagation time on the surface of is measured.

[0004]

In the conventional sound velocity calibrator described above, since the magnet holder 4 is once fixed to the DUT 1, the magnetic force must be released each time the measurement position is changed. In addition, since the flexible belt 2 has heavy objects at both ends, the belt may break or bend, so that care must be taken when handling the belt. Furthermore, since the magnet holder 4 is used, there is a problem that the magnet holder 4 cannot be used except for a ferromagnetic material to be measured.

The present invention has been made to solve such a problem , and can easily change a measurement position.
It is an object of the present invention to obtain a surface acoustic wave velocity measuring device which can prevent a load from being applied to a flexible belt and which can select any material as long as it can transmit a surface wave other than a ferromagnetic material.

[0006]

A surface acoustic wave according to the present invention.
The speed measuring device is a rod or pipe with a circular cross section.
In order to measure the outer circumference of the DUT using surface waves,
The sound velocity at which the surface wave propagates to the measured object
Flexibility along the surface of the DUT
And a fixed length belt with one end
A first belt holder and the first belt holder.
Block and the measurement
A reflector that can sometimes contact the DUT,
A shaft that supports the rotation of the lock and this shaft
Slide block and slide block
Measure the slide shaft to be guided and the belt
Always slide blocks to extend straight when not in use
If it acts to push it toward the tip of the slide shaft
And a second belt holder for fixing the other end of the belt
And a surface wave attached to the second belt holder.
A probe housing for accommodating the probe, and the surface wave
Contact rubber placed between probe and DUT
And hold the contact rubber, and
The shoe attached to the housing and the probe
A pin that supports the jig in rotation, and an arm that fixes this pin
And a button for fixing the slide shaft and the arm.
And a handle attached to this body.
The contact rubber and the reflector are separated by a certain distance.
It is fixed to the belt at the position.

[0007]

According to the present invention, a surface acoustic wave velocity measuring device is provided with a surface acoustic wave
One that has flexibility along the surface of the device under test
Press the fixed-length belt against the workpiece during measurement
This allows the slide shaft fixed to the body to
The slide block moves and blocks around the shaft
Rotates. The rotation of this block causes the reflector to be measured.
Reflective plate and core
The contact rubber keeps a certain distance from the
Fixed to the default and contact from surface wave probe
The surface wave transmitted through the rubber moves on the circumferential surface of the DUT.
Propagation, reflection at the reflector, surface wave via the reverse path
Inject into the probe. This allows the reflector and contact
Measuring the propagation time of a surface wave between two points with the traversal
Thus, the sound speed for calibration can be obtained.

[0008]

【Example】

Embodiment 1 FIG. Hereinafter, an embodiment of the present invention will be described. 1 is a front view of the present invention, FIG. 2 is a plan view, and FIG. 3 is a sectional view of a surface acoustic wave probe. In the figure, 2
And 5 to 9 are exactly the same as the above-mentioned conventional apparatus.
10 is a first belt holder for fixing the belt 2, 11 is a block for attaching the first belt holder 10, 1
Reference numeral 2 denotes a shaft for rotatably supporting the block 11, reference numeral 13 denotes a slide block for fixing the shaft 12, reference numeral 14 denotes a slide shaft for sliding the slide block 13, reference numeral 15 denotes a spring acting to pull the belt 2, and reference numeral 16 denotes the belt. A second belt holder 17 for fixing the other end of the second belt holder 17; a pin 18 for rotatably supporting the probe housing 6 attached to the second belt holder 16;
Is an arm for fixing the pin 17; 19 is a body for fixing the slide shaft 14 and the arm 18;
Is a handle attached to this body.

In the surface acoustic wave velocity measuring device constructed as described above, the probe housing 6 is rotated by the arm 18 fixed to the body 19 and the pin 17 fixed to the arm 18, and the shoe 9 is attached to the DUT 1. Following this, the contact rubber 8 is compressed and the surface wave from the surface wave probe 7 can be propagated. On the other hand, the DUT 1
The belt 2 is pressed against the slide block 13 on the slide shaft 14 fixed to the body 19.
However, while the belt 2 moves by following the DUT 1, the block 11 finally rotates around the shaft 12 fixed to the slide block 13, and the reflector 5 is pressed against the DUT 1. to contact Te. The surface wave transmitted to the device under test 1 via the surface wave probe 7 and the contact rubber 8 in this manner is generated when the surface of the device under test 1 has a reflection source.
In this case, the reflection plate 5 propagates on the circumferential surface of the DUT 1 and is pressed against and contacts the DUT 1 while maintaining a predetermined distance by the belt 2.
, The reflected surface wave is incident on the surface acoustic wave probe 7 via the reverse path.

[0010]

Since the present invention is constructed as described above, it has a handle and has a contact line with an object to be measured.
Bar, belt, to press like reflector is in contact
The reflector and the contact rubber against the DUT
Easily secure a certain distance, and because supports the parts from Ikoto load such to the belt at the body, Bell
They do not break or bend. Also , if the object to be measured is made of any material as long as
Even so, the propagation speed can be measured, and there is an effect that the material is not selected.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a plan view showing one embodiment of the present invention.

FIG. 3 is a cross-sectional view of a surface acoustic wave probe section showing one embodiment of the present invention.

FIG. 4 is a bird's-eye view showing a conventional sound speed calibrator.

[Explanation of symbols]

 2 Belt 5 Reflector 6 Probe Housing 7 Surface Wave Probe 8 Contact Rubber 9 Shu 10 First Belt Holder 11 Block 12 Shaft 13 Slide Block 14 Slide Shaft 15 Spring 16 Second Belt Holder 17 Pin 18 Arm 19 Body 20 handle

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Naoto Yamada 325 Kamimachiya, Kamakura-shi Mitsubishi Electric Corporation Kamakura Works (72) Inventor Shigeaki Tateno 730 Kamimachiya, Kamakura-shi Mitsubishi Electric Engineering Kamakura Works (58) Field surveyed (Int.Cl. ⁶ , DB name) G01B 17/00 G01N 29/22 G01S 7/526

Claims (1)

(57) [Claims] 1. A bar-shaped or pipe-shaped object to be measured having a circular cross section is measured by using a surface wave.
Seek speed of sound propagation of the surface wave to advance the object to be measured
In a surface acoustic wave velocity measuring device , a fixed length belt having flexibility along a surface of an object to be measured, a first belt holder for fixing one end of the belt, and a first belt holder are provided. A mounting block, a reflector attached to the block and capable of contacting an object to be measured during measurement, a shaft for rotatably supporting the block, a slide block for supporting the shaft, and a slide shaft for sliding the slide block A spring that always presses the slide block toward the tip of the slide shaft so as to extend the belt straight when not measured, a second belt holder that fixes the other end of the belt, A probe housing attached to the belt holder and housing the surface acoustic wave probe,
A contact rubber disposed between the surface acoustic wave probe and the device under test, a shoe that holds the contact rubber and is attached to the probe housing, a pin that rotationally supports the probe housing, and fixes the pin An arm, a body for fixing the slide shaft and the arm, and a handle attached to the body, wherein the contact rubber and the reflector are fixed distance apart from each other.
A surface acoustic wave velocity measuring device characterized by being fixed to a belt at a separated position .