JPH054389Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention can be attached to a transducer for underwater acoustics,
The present invention relates to the structure of a protective cover for a transducer that protects the transducer.

[Conventional technology]

In a wave transmitter/receiver used underwater, the wave transmitting/receiving surface, which is a delicate device, must be protected from various impacts such as when being dropped into the water or from collisions with floating objects in the water.

FIG. 4 is a perspective view showing a conventional example of this type of protective cover for a transducer, and FIG. 5 is a side view showing the conventional example attached to a transducer.

In the figure, 1 is a protective cover made of synthetic resin in the shape of a truncated cone with a bottom, 2 is a mounting hole provided on the transducer 3 side of the protective cover 1, and 4 is a drain hole provided on the bottom surface. The protective cover 1 having the above structure is attached to the wave transmitter/receiver 3 via the post 5, as shown in FIG. 5, to protect the wave transmitting/receiving surface 3a from various shocks.

[Problem that the invention attempts to solve]

However, according to the prior art with the above configuration, a transmission loss occurs due to the protective cover as shown in FIG.

Although the sound trapped between the protective cover and the transducer is small compared to the energy of the sound that passes through the protective cover, this trapped sound is caused by the resonance mode of the protective cover and the high-order This occurs because, by exciting the spurious, the sound transmitted through the aforementioned protective cover is added to the sound transmitted and received by the transducer in such a way as to cancel or intensify it.

Since this additional sound differs slightly depending on the direction and frequency of the sound, there was a problem in that the transducer could not obtain stable performance.

In view of the above problems, it is an object of the present invention to provide a protective cover for a transducer that protects the transducer from various impacts without damaging the characteristics of the transducer.

[Means to solve the problem]

This invention consists of a synthetic resin formed into a cylindrical shape with a bottom or a shape close to a truncated cone corresponding to the shape and size of the wave transmitting and receiving surface in order to cover and protect the entire wave transmitting and receiving surface of the transducer. The protective cover for the transducer is characterized in that a slit is provided at a location corresponding to the direction of the directivity of the transducer.

[Effect]

With the above configuration, the present invention can be attached to a transducer,
While protecting the transmitting and receiving surface of the transducer from various shocks, the slit removes the resonance mode of the protective cover and high-order spurious from the usage band, and traps the sound that passes through the protective cover between the protective cover and the transducer. It is possible to prevent excitation caused by noise.

〔Example〕

Examples will be described below with reference to the drawings.

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is a side view showing the same embodiment attached to a transducer.

In the figure, 6 is a protective cover made of synthetic resin with excellent acoustic performance and shaped like a truncated cone.

7 is a mounting hole provided on the upper end frame 6a of the protective cover 6 for attaching the protective cover 6 to the transducer 3, and 8 is a drain hole provided on the bottom surface 6b of the protective cover 6. In this embodiment, one piece is arranged at the center of the bottom surface and four pieces are arranged radially.

Reference numeral 9 denotes a slit provided on the side surface 6c of the protective cover 6, and the slit 9
The length is set to be approximately the same as a. In this embodiment, the transducer 3 to be protected is assumed to have directivity in all directions, and is arranged at positions equally divided into four circumferences of the side surface 6c.

The protective cover 6 having the above structure is attached to the transducer 3 via the post 5 as shown in FIG. 2 to protect the wave transmitting/receiving surface 3a of the transducer 3 from various impacts.

At this time, the plurality of slits 9 provided on the side surface 6c of the protective cover 6 remove the resonance mode of the protective cover 6 and high-order spurious from the usable band, so that the sound transmitted through the protective cover 6 is transmitted between the protective cover 6 and the transducer. There is no excitation due to the sound trapped between 3 and 3.

FIG. 3 is a graph showing transmission loss data of the protective cover 6 having the above-mentioned configuration, and according to this example, it was possible to maintain approximately 0 _dB for each frequency.

[Effect of idea]

As explained in detail above, according to the present invention, a protective cover for a transducer made of synthetic resin is formed into a cylindrical shape with a bottom or a shape close to a truncated cone corresponding to the shape and size of the wave transmitting/receiving surface of the transducer. In the above, slits were provided at locations corresponding to the direction of directivity of the transducer, so these slits cause the resonance mode of the protective cover and high-order spurious to deviate from the usage band, and the sound that passes through the protective cover is transmitted and received by the protective cover. It is no longer excited by the sound trapped between the wave generators.

This has the effect that the transducer can obtain stable performance while being protected from various shocks.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the present invention;
The figure is a side view showing the same embodiment installed in a transducer, FIG. 3 is a graph showing transmission loss data of the protective cover of the same embodiment, FIG. 4 is a perspective view showing the conventional example, and FIG. The figure is a side view showing the conventional example attached to a transducer, and FIG. 6 is a graph showing transmission loss data of the protective cover of the conventional example. 3... Transducer/receiver, 6... Protective cover, 7... Mounting hole, 8... Drainage hole, 9... Slit.

Claims (1)

[Claims for Utility Model Registration] 1. In order to cover and protect the entire wave transmitting/receiving surface of the transducer, the transmitting/receiving surface should be shaped into a cylindrical shape with a bottom or a shape close to a truncated cone corresponding to the shape and size of the wave transmitting/receiving surface. A protective cover for a transducer made of synthetic resin, characterized in that a slit is provided at a location corresponding to the direction of directivity of the transducer. 2. The protective cover for a transducer as set forth in claim 1, wherein the length of the slit is approximately the same as the length of the wave transmitting/receiving surface of the transducer.