JPS5821879B2 - Chiyo Onpa Souji Yuhaki - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to obtaining an ultrasonic transducer with excellent directional characteristics.

For example, in Doppler sonar, as shown in Figure 1,
A plurality of transducers 2A and 2B are installed on the bottom 1 of the ship.

2C is installed with each radiation surface inclined by θ.

Then, by setting the array spacing DI, D2 so that the parallel spacing DAB, DBC of each radiation surface is an integral multiple of the wavelength of the ultrasonic wave, and combining the transmitted and received signals of each transducer, the combined directivity in the θ direction is obtained. Obtainable.

Conventionally, each transducer is mechanically arranged as described above, so when installing the transducer, it is extremely difficult and time consuming to adjust the inclination θ of the radiation surface, the array spacing DI, D2, etc. Installation work was required.

The present invention provides an ultrasonic transducer that does not require the conventional installation work and can easily obtain predetermined directivity characteristics.

The embodiments shown in the drawings will be described below.

In FIG. 2, 3 is a vibrator that converts electrical vibration and mechanical vibration.

A plurality of radiators 4A, 4 are arranged on the vibration surface of the vibrator 3.
B, 4C, . . . are arranged at predetermined intervals.

Each radiator 4A, 4B. 4C... is made of a material with an extremely high coma wave propagation velocity.

As shown in FIG. 3, each of the radiators 4A, 4B, 4C has a radiation surface 5A, 5B, 5C, etc., which is inclined by θ with respect to the vibration surface of the vibrator 3. The slope height is set to one wavelength of the sound wave in the ultrasonic radiation medium.

And radiator 4A. 4B, 4C... are arranged so that the respective radiation surfaces 5A, 5B, 5C... are parallel to each other, and the parallel interval is an integral multiple of the wavelength of the sound wave in the ultrasonic radiation medium. has been done.

Also, each radiator 4A, 4B. 4C... Gap 6A,
A sound wave non-propagating material is inserted in 6B, 6C, . . . .

Therefore, the vibration waves of the vibrator 3 are transmitted to the radiation surfaces 5A and 5 of each radiator.
B, 5C, . . . and sound waves arriving from the outside are transmitted to the vibrator 3 via the radiation surfaces 5A, 5B, 5C, .

The vibration waves generated in the vibrator 3 propagate through each radiator and reach the respective radiation surfaces 5A, 5B, 5C, . . . .

Here, since the radiation surfaces 5A, 5B, 5C, . . . are inclined by θ as described above,

The vibration waves do not reach each part of the radiation surface at the same time, but strictly speaking, they arrive with slight time differences.

However, the slope height of the radiation surface is set to one wavelength in the ultrasonic radiation medium, and each radiator 4A, 4B, 4
Since the propagation velocity of the sound waves in C... is sufficiently higher than the propagation velocity of the sound waves in the radiation medium, the minute time difference mentioned above is so small that it can be ignored.

Therefore, it can be considered that the vibration waves of the vibrator 3 reach each part of the radiation surface in substantially the same phase.

Next, consider the directivity characteristics of the ultrasonic waves radiated from each of the radiation surfaces 5A, 5B, 5C, . . . .

The slope height of each radiation [n5A, 5B, 5C... is set to one wavelength in the ultrasonic radiation medium.

Therefore, when considering an arbitrary radiation surface 51, the radiation surface 51
Since the sound waves emitted in the direction perpendicular to the vibration surface of the vibrator 3 cancel each other out, the sound waves are not transmitted or received in this direction.

Therefore, the sound waves transmitted and received from the radiation surface 51 are transmitted and received in the θ direction with respect to the vibration direction of the vibrator 3.

For each radiation [n5A, 5B, 5C, . . . , the parallel spacing between the radiation surfaces is set to be an integral multiple of the wavelength in the sound wave radiation medium.

Therefore, the sound waves transmitted and received from each of the radiation surfaces 5A, 5B, 5C, etc. in the θ direction and the vibration direction of the vibrator 3 are transmitted and received in the same phase, resulting in a composite directivity characteristic that is sharp in the θ direction. is formed.

Also, as mentioned above, the sound waves arriving at each part of the radiation surface are
Since the light is transmitted to the vibrator 3 in substantially the same phase, the directional characteristic of the vibrator 3 is formed in the above-mentioned θ direction.

Since this directional characteristic is given as a composite directional characteristic of each radiator, it is possible to obtain a sharp directional characteristic that is isometric when formed using a plurality of oscillators 3.

In this way, in the present invention, a sharp directivity characteristic in a predetermined direction can be obtained for each individual transducer, so when this transducer is installed on the bottom of a ship, the spacing between the transducers, the inclination of the transducer, etc. It is not necessary to adjust each time, and it is sufficient to simply arrange the individual vibrators in a plane direction.

Therefore, the work of installing the vibrator is significantly simplified compared to the conventional method.

In addition, in FIG. 2, radiators 4A, 4B, 4C...
- has been explained as if the individual radiators were arranged on the vibrator, but as shown in Fig. 4, the diagonally shaded portions of the metal body 7 are cut to form the radiators 4A, 4B, 4C, etc. This makes it very easy to arrange and install each radiator.

[Brief explanation of the drawing]

FIG. 1 is a principle diagram for explaining the combined directivity characteristics of an ultrasonic transducer, and FIGS. 2 to 4 show embodiments of the present invention.

Claims (1)

[Claims] 1. The ultrasonic radiation surface (wave receiving surface) is inclined by a predetermined angle with respect to the vibration surface of the vibrator that converts electrical vibration into mechanical vibration, and the slope height is 1 of the sound wave in the ultrasonic radiation medium.
A plurality of ultrasonic radiators are arranged on the vibrating surface of the vibrator, and the radiating surfaces (receiving surfaces) of each radiator are parallel to each other, and the parallel interval is set to the wavelength of the ultrasonic wave in the ultrasonic radiation medium. An ultrasonic transducer arranged so that the wavelength is an integer multiple of the wavelength.