JPH0129894Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention provides a drip-proof microphone that can achieve drip-proofing without affecting the characteristics of the microphone.

When using a microphone in a place where it is exposed to water, such as in the shower, or outdoors, especially in light rain, the sound intake port may become blocked by water droplets, which may change the characteristics of the microphone. Water sometimes entered the microphone through the sound intake, causing acoustic and electrical disturbances.

In response to this, various drip-proof microphones have been conventionally provided.

For example, a waterproof coating made of a resin film such as polyester is interposed between the diaphragm and the sound intake, or a water-repellent coating is applied between the diaphragm and the sound intake. Some have a metal mesh interposed between them. All of these are drip-proof measures that allow water to enter the case from the sound intake port, so it is impossible to prevent the sound intake port from being blocked by water droplets. It was not inherently desirable. Furthermore, in the case of the former, sound transmission is poor due to the coating, which affects the microphone characteristics and limits the range of use.

On the other hand, some models cover the entire microphone with a breathable polymer layer to prevent water from entering the microphone case, but this increases the volume of the microphone and is not desirable.

The present invention eliminates the above-mentioned conventional drawbacks and is applicable not only to electrostatic microphones but also to various types of microphones such as dynamic, piezoelectric, and electromagnetic microphones. In addition, the aim is to achieve drip-proofing without impairing the microphone characteristics, and instead of taking measures after the sound intake, we take measures before the sound intake, to be more precise, at the sound intake. It is said that

In order to achieve this purpose, according to this invention, a drip-proof body with a sound path formed at the sound intake is provided, and this drip-proof body is made of a material whose critical surface tension is smaller than the surface tension of water. so that it forms.

An embodiment of the present invention will be described below with reference to the drawings. The figure is a sectional view of a drip-proof electrostatic microphone that is an embodiment of the present invention. Reference numeral 1 denotes a cylindrical protective case, and a sound port 2, which is a sound intake port, is formed on the front surface of the case. 2A is a sound introduction tube formed around the sound port 2, and the opening of this sound introduction tube 2A substantially serves as the sound port. 3 is sound guide 3
It is a drip-proof body having A, and a tube made of a material with low critical surface tension, for example, a fluororesin such as polytetrafluoroethylene, is used. This tube 3 made of fluororesin is press-fitted and fixed into the sound introduction tube 2A. In addition, 4 is a vibrating membrane, 5 is a fixed electrode,
6 is an electric film, and 7 is an impedance converter.

In the above embodiment, the drip-proof body 3 is attached to the sound introduction tube 2A formed around the sound port 2.
The drip-proof body 3 of the sound port 2 may be directly attached without providing the hole A. Further, in the above embodiment, the case where there is one sound port 2 has been described, but the number of sound ports may be any number. It is sufficient to attach a drip-proof body to each sound port.

As described above, according to the present invention, even if water droplets form, the so-called water droplets will be repelled by the drip-proof body, and the water will not enter the inside of the microphone.
Therefore, since the sound port is drip-proof, compared to microphones where the inside of the microphone is drip-proof, there is no inconvenience caused by water that has entered the inside of the microphone that takes time to dry. Moreover, the shape of the microphone itself is not large. Furthermore, by appropriately selecting the inner diameter (size of the sound path), length, and number of the drip-proof body, there are significant practical effects such as not affecting the frequency characteristics of the microphone.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the present invention. 2: Sound port, 3: Drip-proof body, 3A: Sound path.

Claims (1)

[Claims for Utility Model Registration] 1. A drip-proof body 3 having a sound path 3A is attached to the sound port 2, and the drip-proof body 3 is made of a material whose critical surface tension is smaller than the surface tension of water. A drip-proof microphone. 2. The drip-proof microphone according to claim (1), in which the drip-proof body 3 is a tube made of fluororesin.