JPS61296897A - Ultrasonic oscillator - Google Patents

Abstract

PURPOSE:To select the size of a beam, make a side lobe value small, and obtain a stable shape by bonding a piezoelectric ceramic oscillator in an inner side of a bottom surface part of a case of truncated cone in section and holding the case by a resilient vibration isorator having a circle hole of a larger diameter than the bottom surface part. CONSTITUTION:An oscillator 3 is bonded to an inner side of a bottom surface part 1 of a case 2 of truncated cone in section and having the bottom surface part 1, and the case 2 is held by a resilient vibration isorator 7 having a circle hole 8 having a larger diameter than the bottom surface part 1 of the case 2 and an acoustic tube 10 is formed by the circle hole 8. The oscillator 3, the case 2 and an output terminal 6 are respectively connected by a lead wire 5. Thereby, the size of an ultrasonic beam can be selected by the diameter of the circle hole and the side lobe value can be made small to obtain a stable beam formation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an ultrasonic transducer using a piezoelectric ceramic transducer.

[Background technology]

Conventionally, a drip-proof ultrasonic vibrator has a piezoelectric ceramic vibrator (hereinafter simply vibrating) inside the bottom fl of a case (2) having a bottom fl) and a truncated conical cross section, as shown in FIG. A bimorph oscillator was formed by pasting the case (3), and the open end of the case (2) was held by the vibration holder 5 (4) so that the bottom part m vibrated. Lead wires (5) connect the vibrator (3) and case (2) to the output terminal (6), respectively. This device had a drawback in the ultrasonic beam directivity, as shown in FIG. 5, that side rows B were formed on both sides of a main row A projecting in the center.

[Purpose of the invention]

An object of the present invention is to make it possible to select the thickness of an ultrasonic beam and to reduce the +j-idrow value to obtain a stable beam shape. [Disclosure of the Invention] In FIG. A vibrator (3) is attached to the inside of the bottom part f1+ of a case (2) having a bottom part (1) and a truncated conical cross section. The elastic vibration isolator (7) is located at the bottom part f1 of the case (2).
) has a circular hole (8) with a larger diameter than the diameter of the case (2), and is formed so as to be in close contact with the inclined surface (9) of the case (2), and the case (2) is held by this elastic vibration isolator (7)K. The circular hole (8) forms an acoustic tube (101).The lead wire (5) connects the vibrator (3) and the case (2) to the output terminal (6). The relationship between the diameter of the circular hole (8) and the half-angle of the ultrasonic beam is shown in Figure 2, as the diameter becomes smaller, the beam half-angle becomes larger.
As shown in the figure, side rows can be eliminated and a stable beam shape can be achieved.

〔Effect of the invention〕

As described above, the present invention provides an elastic vibration isolator in which a piezoelectric ceramic vibrator is attached to the inside of the bottom part having a truncated conical cross section, and an acoustic tube is formed with a circular hole having a diameter larger than the diameter of the abdominal part. Since the case is held by the body, the thickness of the ultrasonic beam can be selected depending on the diameter of the circular hole, and the side-low value can be reduced, resulting in a stable beam shape.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of an embodiment of the present invention, Fig. 2 is a characteristic diagram of the relationship between the diameter of the circular hole and the beam half angle, Fig. 3 is a characteristic diagram of the ultrasonic beam characteristic shown in the above, and Fig. 4 is a vertical sectional view of the conventional example, and FIG. 5 is an ultrasonic beam characteristic diagram of the same as above. (1)...Bottom part, (2)...Case, (3)...
Piezoelectric ceramic vibrator, (7)...Elastic vibration isolator, (8
)...Circular hole, (lO)...Acoustic tube 0

Claims (1)

[Claims] (1) A piezoelectric ceramic vibrator is attached to the inside of the bottom of a case having a truncated conical cross section, and an elastic vibration isolator is used to form an acoustic tube with a circular hole having a diameter larger than the diameter of the bottom. An ultrasonic vibrator characterized by holding a case.