JPH02101894A - Acoustic vibrator - Google Patents

Abstract

PURPOSE:To attenuate intermediate and high frequency range sound causing a noise sound by providing a speaker driver and a tubular cavity whose inner wall is flexible into a foamed body and opening one end of the cavity and one end of a silencer tube toward an acoustic transducing chamber. CONSTITUTION:A driver unit 18 connecting to a resonance tube 14 and a silencing tube 16 is embedded in a foamed body 12. The resonance tube 14 is bent and other end 14b and other end 16b of the silencing tube 16 are opposite to each other with a hollow part 32 of a required length placed inbetween. The diameter of the hollow part 32 is nearly the same as that of the resonance tube 14. The acoustic vibration of a speaker driven by a driver unit 18 causes resonance in a long air column in the bent resonance tube 14, an ultralow frequency sound is delivered with a high efficiency and sensed directly by human body. The intermediate and high frequency range sound being noise is cancelled in the silencing tube 16 and attenuated and not heard from an opening 16b of the silencing tube 16. Moreover, a low frequency range sound is amplified by the silencing tube 16 and the acoustic vibration is much effectively adored.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an acoustic vibration device that simultaneously generates sound and vibration.

[Prior Art] Conventionally, there is an acoustic vibration device in which a flexible tube is connected to a driver unit having a built-in speaker and these are embedded inside a foam body.

In this acoustic vibration device, when an electric signal containing music or the like is input to the driver unit, it is converted into acoustic vibration by the speaker, and this acoustic vibration causes resonance in the flexible tube, allowing the person to listen to the music, etc. You can experience it not only through your ears but also directly as vibrations. In particular, since it utilizes the resonance of long air columns, it is capable of highly efficient transmission of deep bass sounds.

[Problems to be Solved by the Invention] However, in the acoustic vibration device described above, when the speaker inside the driver unit vibrates, for example, 1
Noise in the mid-high frequency range of 20Hz or higher was sometimes generated. Then, there was a problem that this noise leaked from the flexible tube.

[Object of the Invention] The present invention provides an acoustic vibration device that attenuates middle and high frequency sounds that become noise.

[Means for Solving the Problems] The acoustic vibration device of the present invention includes a driver unit having a vibration force in an acoustic conversion chamber, and a tubular cavity having a flexible inner wall, which is provided inside a foam body. One end of the cavity opens into the acoustic conversion chamber of the driver unit, and one end of a muffling tube for attenuating the middle and high ranges opens into the acoustic conversion chamber.

[Function] The speaker in the acoustic conversion chamber of the driver unit causes resonance in the tubular cavity inside the foam to obtain acoustic vibrations. In addition, the noise from the middle and high frequency ranges is attenuated by the muffling tube that opens into the acoustic conversion chamber, and cannot be heard outside the acoustic vibration device.

[Example] Hereinafter, the present invention will be explained in detail based on FIGS. 1 and 2.

(10) is an acoustic vibration device, and (12) is a foam made of urethane. (14) is a tubular cavity with a flexible inner wall, and in this example, a bellows-like flexible tube made of polypropylene, vinyl chloride resin, etc. is used to achieve resonance. Both ends (14a) and (14b) of the resonant tube (14) are open. (16
) is a muffling tube, which is a bellows-shaped flexible tube similar to the resonance tube (14), and has both ends (lea).
(18b) is open.

(18) is a driver unit. As shown in FIG. 2, the acoustic conversion chamber (20) inside the rectangular parallelepiped-shaped driver unit (18) has a partition plate (
22) into an upper chamber (20a) and a lower chamber (20b). That is, the lower chamber (20b) has a rectangular parallelepiped shape, but the upper chamber (20a) has a thin rectangular parallelepiped-shaped chamber part above the lower chamber (20b) and another rectangular parallelepiped-shaped chamber extending downward from the side of this part. Consisting of The partition plate (22) has an opening (
24) is provided, and the speaker (2G) is connected to the opening (24).
It is attached to the lower chamber (20b) so as to face the upper chamber (20a) through it. A circular opening is provided in the side wall, and a vibrator (28) having a circular cross section is fitted into this opening.

The vibrator (30) passes through the side wall of the driver unit (18) and faces the lower chamber (20b). Both vibrators (28)
(30) consists of a rigid body. One end (14a) of the resonance tube (14) is connected to the vibrator (30) and opens into the lower chamber (20b). Also, a silencer pipe (1B)
The - end (lea) is connected to the vibrator (28) and opens into the upper chamber (20a).

As shown in FIG. 1, with the driver unit (18) connected to the resonance tube (14) and the muffling tube (1B),
These are embedded inside the foam (12). The resonant resonant tube (14) is bent, and the resonant resonant tube (14) is bent.
4) other end (14b) and the other end (1
8b) are provided so as to face each other with a hollow portion (32) of a required length in between. This hollow part (32) has a circular cross section and is approximately the same size as the diameter of the resonance tube (14), and may be linear as shown in FIG.
Alternatively, it may be curved.

Electrical signals such as music are converted into acoustic vibrations by the speaker (26) of the driver unit (18), and this acoustic vibration passes through the royal chamber (20b) and causes resonance in the bent resonant tube (14), causing the person to When you touch the acoustic vibration device (IO), you can experience music directly. In particular, since it utilizes the resonance of long air columns, it is capable of highly efficient transmission of deep bass sounds.

The mid- and high-range units that produce noise are passed through the vibrator (28) and then passed through the muffler tube (
1B) and are attenuated by canceling each other out in the silencer tube (1B).
6) cannot be heard through the opening (16b). Also,
The muffler tube (1B) causes a bass reflex effect, amplifying low-frequency sounds and making acoustic vibrations more effective.

The length of the resonance tube (14) is preferably 1 m to 5 m in order to cause resonance of a long air column. In addition, it is not limited to flexible tubes, but if the surrounding wall has flexibility, foam (
12) A structure in which a hollow portion is provided inside may be used.

The cross-sectional size and length of the muffler tube (16) are determined by the frequency of the sound to be attenuated. For example, in the case of attenuating sound at frequencies from 300 Hz to 2000 Hz, if the diameter of the muffling tube (16) is 1 CI11 to 3 cffI, the length is preferably about 10 cI11 to 5 Oct II. Further, the muffling tube (1B) may be a flexible tube that causes resonance as in the above embodiment, but
Even if a rigid tube is used in place of this, the effect of attenuating mid- and high-range sounds according to the present invention can be sufficiently obtained.

[Effects of the Invention] According to the acoustic vibration device according to the present invention, middle and high frequency sounds that become noise are attenuated by the action of the muffling tube and cannot be heard outside the acoustic vibration device. Therefore, it is possible to comfortably experience the resonance of the tubular cavity caused by the speaker of the driver unit through the foam.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view of an acoustic vibration device according to an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a driver unit. patent

Claims (1)

[Claims] 1. A driver unit having a speaker in an acoustic conversion chamber and a tubular cavity having a flexible inner wall are provided inside the foam, one end of which opens into the acoustic conversion chamber of the driver unit, and a mid-high frequency range. An acoustic vibration device characterized in that one end of a muffling tube for attenuating sound opens into the acoustic conversion chamber.