JPS5852787Y2 - Variable reverberation microphone device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a microphone device that can vary the amount of reverberation.

FIG. 1 shows a conventional variable reverberation microphone device.

In the same figure a, 11 is a dynamic microphone unit, 12 is a diaphragm, 13, 14.15 is a foamed elastic body provided inside a case 16, 17, respectively, 18 is a movable element, 19° and 20 are inside a case 21, respectively. The diaphragm 19 and the diaphragm 12 constitute a reverberation device provided in the case 16.
, 17, the elastic body 14, and the movable member 18 are acoustically connected through a through hole provided in the movable member 18.

In such a configuration, the movable element 18 is indicated by arrow A in the figure.

By driving in the B direction, the bubble density of the elastic body changes completely, and the space between the diaphragms 12 and 19 is acoustically opened and closed, thereby adjusting the amount of reverberation.

On the other hand, in the figure bG'l-, 23 denotes a microphone unit made of, for example, an electret for direct sound, provided in a case 24 having a plurality of through holes, 25.26.2
7 is a diaphragm and a coil spring that constitute a reverberation device provided in the case 28, and 29 is a microphone unit made of, for example, an electret for reverberant sound provided in the case 28.

The output signal of this microphone unit 29.degree. 23 is supplied to a mixing circuit 30, where the amount of reverberation is adjusted.

In the case of the microphone having the configuration shown in FIG.
It has the disadvantage that the sound pressure at frequencies up to 1.5 KHz is very low and reverberation is difficult to produce.

In addition, in the case of the same figure, although a sufficient amount of reverberation can be obtained, it has the disadvantage that the sound quality is not good because only the reverberant sound obtained by the microphone unit 29 and the direct sound obtained by the microphone unit 23 are synthesized. There is.

Furthermore, both microphones have the disadvantage that when the amount of reverberation is varied, the reverberation frequency does not change naturally, making it impossible to obtain a natural hearing sensation.

This idea was made based on the above circumstances, and as the reverberation frequency changes naturally as the amount of reverberation changes, a good hearing sensation can be obtained, and sufficient reverberant sound in the low range can be obtained, and the sound quality is also extremely good. The present invention aims to provide a variable reverberation amount microphone device.

An embodiment of this invention will be described below with reference to the drawings.

In FIGS. 2a and 2b, 31 is a cylindrical housing with a bottom, for example, and a flange 32 is provided at a part of the periphery of the opening of this housing 31.

A diaphragm 33 constituting a reverberation device is provided within the opening of the casing 31, and an elastic member such as a coil spring 34 is provided between the diaphragm 33 and the bottom surface of the casing 31.

A fixed chamber 35 that is open toward the flange 32 is integrally formed in the opening of the casing 31 .

A cutout portion 36 of a predetermined shape is formed at the top end of the fixed chamber 35 in the frontage direction, and a side microphone unit 37 facing the opening is provided on the side surface facing the opening.

On the other hand, this fixed chamber 35 has a movable chamber 3 which opens in the opposite direction to the opening direction of the fixed chamber and forms a vacant chamber 38 together with the fixed chamber.
9 is slidably fitted.

In this fitted state, the lower end of the movable chamber 39 in the frontage direction passes through the side surface of the fixed chamber 35, and a through hole 40 having an opening area smaller than the flange 32 is formed at the base end of the lower surface.

Further, a notch 41 is formed at the front end of the upper surface of the moving chamber 39 in the frontage direction, facing the notch 36 and being longer than the notch.

In the above configuration, when the moving chamber 39 is pushed into the fixed chamber 35 as shown in FIG.
The area of the opening formed by the casing is reduced,
The through hole 40 of the moving chamber 39 faces the diaphragm 33.

In this state, sound waves entering from the opening formed by the notch 36.41 directly enter the microphone unit 37 as shown by the dotted arrow, and also enter the diaphragm 37 through the through hole 40.
Drive 3.

The sound waves generated by the diaphragm 33 enter the microphone unit 31 as reverberation components, and further drive the diaphragm 33.

On the other hand, when the moving chamber 39 is slid in the direction of arrow C in the figure and pulled out from the fixed chamber 35 from the above state, the area of the opening formed by the notch 36.41 gradually increases, and the area of the opening formed by the through hole 40 and the diaphragm The facing area of 33 gradually becomes smaller.

Therefore, the amount of reverberation gradually decreases, and the reverberation frequency also gradually increases, so that the reverberation decreases in a natural manner.

In the state shown in the figure, the opening of the housing 31 is completely closed by the lower surface of the moving chamber 35, so the microphone unit 37 has a notch 36 as shown by the dotted line.
Only sound waves from the opening formed by 41 will enter.

According to the embodiment described above, the opening by the notch 36, 41 and the through hole 4 correspond to the sliding state of the moving chamber 39.
The opening area of 0 is made to change in an inverse relationship.

Therefore, the reverberation changes in a natural manner.

Further, since the fixed chamber 35 and the movable chamber 39 form the empty chamber 38, the sound pressure of the low frequency component of reverberation is increased and the sound quality is also improved.

Furthermore, as shown in Figure 2, when no reverberation is added, the opening area of the notch 36 and 41 becomes a dog, so the influence of reflections in the empty room 38 is reduced9, and only direct sound is generated. can prevent sound quality deterioration.

Note that this invention is not limited to the above embodiments,
For example, the movable chamber 39 may be provided to rotate relative to the fixed chamber 35.

At this time, the positional relationship between the notches 36, 41, the through hole 30, and the collar 32 may be changed as appropriate.

It goes without saying that various other modifications can be made without departing from the gist of the invention.

As described in detail above, according to this invention, as the amount of reverberation is varied, the reverberation frequency 7>E6 changes naturally to provide a good hearing sensation, and sufficient reverberant sound in the low range can be obtained.
A variable reverberation microphone device with extremely good sound quality can be provided.

[Brief explanation of drawings]

FIGS. 1a and 1b are side sectional views showing different conventional reverberation variable microphone devices, and FIG. FIG. 3 is a side sectional view showing an embodiment of a variable reverberation amount type microphone device according to the B-cigarette device, showing different operating states. 31... Housing, 33... Vibration plate, 34
...... Coil spring, 35... Fixed chamber, 36, 41... Notch, 37...
・Microphone unit, 38...Vacant room, 39
-...Movement room, 40...Through hole.

Claims (1)

[Scope of utility model registration request] A first casing in which a diaphragm is provided in the opening with an elastic member interposed therebetween, a fixed chamber provided in communication with the opening of the first casing, and a diaphragm that slides relative to the fixed chamber. a movable chamber which is freely fitted and whose communication area with the opening of the first casing is varied according to the sliding state, and whose communication area between the fixed chamber and the outside is varied in the opposite manner; 1. A variable reverberation amount microphone device comprising: a microphone unit provided in a space formed by a chamber and a fixed chamber.