JPS583438B2 - microphone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a microphone that can be operated to have arbitrary directivity by combining several microphone units each having at least two mechanical coupling parts and two electrical coupling parts. .

In the past, microphones with large-area sensing sections have rarely been seen; instead, a unidirectional microphone consisting of a transducer with a diaphragm 1, a back hole 2, and an amplifier 3, such as the line microphone shown in Figure 1, has been used. The only thing that has been seen is that an acoustic tube 6 with a slit 5 is attached to the front of the acoustic tube 4, and the length and shape of the acoustic tube 6 are changed to obtain beam-like directivity.

The present invention eliminates the drawbacks of the prior art as described above.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 5.

Reference numeral 1 denotes a microphone unit formed in a cylindrical shape, and has a convex coupling part 8 on the upper end surface for mechanical and electrical coupling.
A concave coupling part 9 is provided on the lower end surface of the convex coupling part 8 to be mechanically and electrically coupled to the convex coupling part 8. It has a microphone unit 7 on the top surface and an electric
It has a convex connecting part 11 for mechanically connecting,
It is assembled into a support stand 13 having a cord 12 connected to this coupling part 11.

As shown in FIG. 3, the microphone unit 7 includes a microphone unit case 15 which is cylindrical and has a sound wave incidence hole 14 on one circumferential surface, the above-mentioned coupling part 8 on the upper end face, and the coupling part 9 on the lower end face. It is composed of a polymer piezoelectric film 17 attached to a frame 16 formed to have an arcuate curvature, and a cover plate 18 that forms a peripheral wall of the opening of the microphone unit case 15 at the curved opening of the microphone unit case 15. has been done.

By using the polymer piezoelectric film 17 in this way, a microphone unit 7 with a large area can be obtained, and by connecting a plurality of microphone units 7 using the connecting parts 8 and 9, the directivity can be changed. Can be done.

When one microphone unit 7 is used, and when three
FIG. 4 shows the change in directivity when the two are combined.

In FIG. 4, curve a is the characteristic in the direction perpendicular to the axial direction of the microphone unit case 15 of one microphone and three microphones combined, and curve b is the characteristic of the microphone unit 7 in the direction perpendicular to the axial direction.
Curve C is the characteristic in the case axial direction when there are three microphone units 7.

As can be seen from this characteristic, the frequency at which sound waves from the axial direction of the microphone case are blocked is determined by the total length of the combination of connected microphone units 7, and the longer the length, the stronger the directivity in the axial direction of the case. It generates almost no output for sound waves above that frequency, allowing for directional use.

For example, in a conference, if a long overall length combination of multiple microphone units 7 is used as shown in Fig. 5, it will be omnidirectional in the horizontal plane of the conference hall and will have low sensitivity in the vertical direction. This means that extra noise can be removed.

As described above, since the microphone of the present invention is configured, the directivity can be arbitrarily selected by setting the number of microphone units to be combined according to the application, and the configuration is simple and inexpensive, and has industrial value. It is a big thing.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional microphone, FIG. 2 is an exploded perspective view showing an embodiment of the microphone of the present invention, and FIG.
The figure is an exploded perspective view showing the configuration of the microphone unit.
FIG. 4 is a sound pressure frequency characteristic diagram of the microphone, and FIG. 5 is an explanatory diagram of directivity showing an example of use of the microphone. 7...Microphone unit, 8,9...
...Coupling part, 14...Sound wave incidence hole, 15...
... Microphone unit case, 16 ... Frame, 17 ... Polymer piezoelectric film, 18 ...
...Lid plate.

Claims (1)

[Claims] 1. A microphone unit that is constructed by incorporating a polymer piezoelectric film in the height direction of a case, and that is provided with coupling parts that can be mechanically and electrically coupled to the upper and lower end surfaces of the case,
A microphone characterized in that it is configured so that it can be coupled to each other in the vertical direction. 2. The microphone according to claim 1, characterized in that a sound wave entrance hole is provided on one circumferential surface of the case.