JPH0664183U - Underwater transducer - Google Patents

Abstract

(57) [Abstract] [Purpose] To be able to absorb unnecessary sound waves, reduce acoustic noise, and use it in a wide frequency band in an underwater transmitter / receiver attached to a vehicle that is traveling underwater. To do. [Structure] A rectifying cover 7 is provided to cover a plurality of sound wave absorbers 6 arranged around the underwater transducer 3. The rectifying cover 7 has excellent sound transmission and has a smooth outer shape, and a pressure balance structure including minute holes 7a is provided in a part thereof.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to the structure of an underwater transducer mounted on a vehicle.

[0002]

[Prior art]

 FIG. 2 is a side view showing a conventional underwater transducer. In the figure, 1 is a body for traveling underwater 2, 3 is an underwater transducer, 4 is a tapered component, and this tapered component 4 is at the joint between the traveling body 1 and the underwater transceiver 3. It is attached and can be acoustically regarded as a rigid body. Reference numeral 5 is a sound wave transmitted and received by the underwater transducer 3.

In the underwater transmitter / receiver with this configuration, the direction of the sound wave 5 transmitted / received by the underwater transmitter / receiver 3 is controlled by the tapered component 4 so that the required directivity is obtained.

FIG. 3 is a side view showing another conventional underwater transducer. In the figure, 6 is a wedge-shaped sound absorber. The wedge-shaped sound wave absorber 6 is attached to the joint between the underwater vehicle 1 and the underwater transducer 3.

The material of the sound wave absorber 6 is made of sound absorbing rubber, wood, or the like, and its shape is wedge-shaped in order to reduce reflection on the surface of the medium and the sound wave absorber due to the difference in solid impedance. It is processed into many and arranged in large numbers.

Further, the height of the sound wave absorber (for example, the dimension from the tip to the bottom surface) is set to approximately 1/6 or more of the maximum wavelength of the sound wave to be absorbed in order to obtain sufficient absorption characteristics.

Next, in the underwater transducer with this configuration, a part of the sound wave 5 transmitted and received by the underwater transducer 3 is absorbed by the wedge-shaped sound absorber 6, and the sound wave influences the directivity. I decided not to do it.

[0008]

[Problems to be solved by the device]

 However, in the device having the above configuration, particularly in the underwater transmitter / receiver shown in FIG. 2, since the intensity and phase of the sound wave reflected by the tapered component depends on the frequency, the usable frequency band becomes narrow. In the underwater transmitter / receiver shown in Fig. 3, the frequency band used is widened, but on the other hand, the interaction between the wedge-shaped sound absorber and water at the time of sailing increases the acoustic resistance due to increased fluid resistance and turbulence. There is a problem that it becomes a source of dynamic noise.

The present invention reduces the interaction with water at the time of traveling in order to eliminate the above-mentioned problems that the used frequency band becomes narrow and becomes a source of acoustic noise at the time of traveling. It is an object of the present invention to provide a device having a wide frequency and excellent directivity by providing a mechanism for eliminating the loss.

[0010]

[Means for Solving the Problems]

 The underwater transducer according to the present invention covers the entire acoustic wave absorber with a rectifying cover having excellent sound transmission and a smooth outer shape.

[0011]

[Action]

 INDUSTRIAL APPLICABILITY The present invention can reduce the interaction with water during running, can significantly reduce acoustic noise, can absorb unnecessary sound waves, and can be used in a wide frequency band. it can.

[0012]

【Example】

 FIG. 1 is a partially cutaway side view showing an embodiment of an underwater transducer according to the present invention. In the figure, 7 is a rectifying cover, and this rectifying cover 7 is made of a polymer material having excellent acoustic transparency. Then, the outer shape of the rectifying cover 7 is shaped into a shape formed by a smooth curve and covers the entire acoustic absorber 6, and screws, adhesives, etc. which are not shown in the running body 1 or the underwater transducer 3 are formed. Fixed by.

In addition, a minute hole 7a is provided in a part of the rectifying cover 7 so as to equalize the pressure inside and outside so as to have water pressure resistance.

In the underwater transmitter / receiver according to this configuration, a part of the sound wave 5 transmitted / received by the underwater transmitter / receiver 3 passes through the rectifying cover 7 and is absorbed by the sound wave absorber 6, so that the sound wave 5 is directed. The effect on sex can be significantly reduced. Moreover, the smooth shape of the rectifying cover 7 can reduce the interaction with water at the time of traveling and can significantly reduce the acoustic noise.

In the above description, the shape of the sound wave absorber is a wedge shape, but the shape is not limited to this and may be a conical shape or the like. Further, a minute hole 7a is provided in a part of the rectifying cover 7 to form a balance structure, but the present invention is not limited to this, and various balance structures may of course be used.

[0016]

[Effect of device]

 As described above in detail, according to the underwater transducer according to the present invention, it is unnecessary because the whole acoustic absorber is covered by the rectifying cover which has excellent sound transmission and has a smooth outer shape. It is possible to absorb various sound waves, reduce acoustic noise, and be used in a wide frequency band.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of an underwater transmitter / receiver according to the present invention.

FIG. 2 is a side view showing a conventional underwater transducer.

FIG. 3 is a side view showing another conventional underwater transducer.

[Explanation of symbols]

 7 Straightening cover 8 Flange

Claims (3)

[Scope of utility model registration request] 1. An underwater transmitter / receiver attached to an underwater vehicle traveling underwater, comprising a rectifying cover for covering an entire acoustic wave absorber arranged around the underwater transmitter / receiver. 2. The underwater transmitter / receiver according to claim 1, wherein the rectifying cover has excellent acoustic transparency and has a smooth outer shape. 3. The underwater transducer according to claim 2, wherein a pressure balance structure is provided on the rectifying cover.