JPS5850478B2 - Chiyo Onpahon - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION As shown in FIG. 1A, the conventional ultrasonic horn has a diameter that gradually increases from the throat a to the opening, and the diameter is approximately elliptical within the throat a of the horn C. The ultrasonic generation source d is housed and attached to the diaphragm, and the directivity characteristic is α in the longitudinal direction of the aperture of the horn C at the throat a of the horn with respect to the central axis of the horn C. When the relationship between the sound pressure Hh in the direction of line segments that intersect at a degree angle and the above α degree is actually measured,
As shown in FIG. The directional characteristic of (
That is, the relationship between the sound pressure Hv in a line segment that intersects the central axis of the horn C with an angle of β degrees in the short axis direction of the horn diameter in the throat a of the horn C and the above β degrees). When actually measured, as shown in Figure 1, 2, when the absolute value of β degree is above a certain value, the sound pressure Hv is large, and even when the absolute value of β degree is above the above fixed value, the sound pressure HV increases as the absolute value of β degree increases. There was a drawback that the directivity characteristics in the short axis direction of the aperture of the horn C were disturbed due to large increases and decreases.

The present invention eliminates the above-mentioned drawbacks of the conventional technology, and the embodiments of the present invention will be described below with reference to the drawings.
4 is a horn whose aperture gradually increases from the throat 2 toward the opening 3 and has an almost elliptical aperture; 4 is an ultrasonic wave generator, which is made up of a piezoelectric crystal piece with a pair of electrodes suitably attached thereto; When a high-frequency voltage is applied between the electrodes, the piezoelectric crystal piece resonates with the high-frequency voltage, vibrates elastically, and generates ultrasonic waves.

An ultrasonic wave source 4 is disposed within the throat 2 of the horn 1 .

Reference numeral 5 denotes a plate having a substantially elliptical hole 6 in the center, which is provided in the throat 2 of the horn 1 in front of the ultrasonic wave generation source 4, and the long axis direction of the hole 6 is the long axis direction of the aperture of the horn 1. This is done perpendicularly to the

The present invention has the above-described configuration, and has a directivity characteristic in the long axis direction of the horn 1 (that is, an angle of α degree is formed in the throat part 2 of the horn 1 in the long axis direction of the horn 1 with respect to the central axis of the horn 1). When we actually measure the relationship between the sound pressure Hh in the intersecting line segment direction and the above α degrees, we find that when the absolute value of α degrees is below a certain value, the sound pressure Hh is large and the absolute value of α degrees is Above the above certain value, the sound pressure Hh decreases and is the same as before, but the horn 1
(i.e., the sound pressure Hv in the direction of a line that intersects the short axis direction of the horn 10 diameter at an angle of β at the throat of the horn 1 with respect to the central axis of the horn 1, and the above As shown in Figure 6, when the absolute value of the β degree is below a certain value, the sound pressure Hv is large, and when the absolute value of the β degree is above the above certain value, the sound pressure Hv is small. 10
Disturbance in the directivity characteristics in the direction of the short axis of the aperture is reduced.

Thus, in the present invention, the ultrasonic wave generation source 4 is disposed within the throat 2 of the horn 1, which has an approximately elliptical diameter that gradually increases in diameter from the throat 2 toward the opening 3. Oval hole 6
A plate body 5 having a diameter is provided in the throat part 2 of the horn 1 in front of the ultrasonic wave generation source 4, and the long axis direction of the hole 6 is perpendicular to the long axis direction of the diameter of the horn 10. This has the effect of preventing the directivity characteristics in the short axis direction of the aperture from being disturbed as a result of actual measurements.

[Brief explanation of the drawing]

FIG. 1 shows a conventional ultrasonic horn, in which FIG. 1A is a sectional view, FIG. 2 to 6 show embodiments of the present invention.
The figure is a front view, and Figure 3 is a sectional view taken along the Y-Y line of the same as above.
Figure 4 is a cross-sectional view taken along the Z-Z line as above, Figures 6 and 6.
The figure is a directional characteristic diagram. 1 is a horn, 2 is a throat, 3 is an opening, 4 is an ultrasonic generation source, 5 is a plate, and 6 is a hole.

Claims (1)

[Claims] 1 An ultrasonic generation source 4 is disposed within the throat 2 of the horn 1, which gradually increases in diameter from the throat 2 toward the opening 3 and has an approximately elliptical diameter, and has an approximately elliptical hole 6 in the center. Plate body 5
is provided in the throat part 2 of the horn 1 in front of the ultrasonic wave generation source 4, and the long axis direction of the hole 6 is perpendicular to the long axis direction of the diameter of the horn 10.