Patent Application
20090067657
The present invention generally relates to a speaker-embeddable seat. The present invention specifically relates to a speaker-embeddable seat with built-in woofer.
A technology is known that transmits a difficult-to-hear low-frequency sound through the skin or bones of a human body (hereinafter sometimes referred to as “body-felt sound”) thereby providing a more real sound. An example of such technology is “Bodysonic” (product name) that is a seat with an embedded electrical-vibration converter.
Such body-felt sound seat is not only popular among audio enthusiasts, but also applied in promoting rehabilitation in the field of medical welfare, and used as a complementary sensitivity apparatus that functions as a sensitivity simulator in amusement industry or education industry.
In a conventional body-felt sound seat, a pillow speaker is attached near to the ears of a person seated in the seat. A vibrator is in a cushion provided at the back and under the hips. A low-frequency sound is converted into vibrations and transmitted to the back and the hips via the vibrator (refer to, for example, Patent Documents 1 to 4).
Patent Document 1: Utility Model Application No. H9-5755
Patent Document 2: Utility Model Application No. H5-33457
Patent Document 3: Utility Model Application No. S59-184026
Patent Document 4: Patent Application No. H4-348155
However, in the conventional body-felt sound seat, a sound field is formed posterior to the head of a person seated in the body-felt sound seat. Hence, the seated person hears the sound coming from backside, which is considered unnatural. Moreover, among the vibrations of a low-frequency sound transmitted at the back and the hips, the vibrations at the back are considered unnatural and fail to provide comfort. Because the body-felt sound seat is configured in such a way that the mechanical vibrations of the low-frequency sound are first generated in the vibrator and then directly transmitted to the seated person, efficiency in reproducing the low-frequency sound that is valuable in a body-felt sound effect is poor.
The present invention has been achieved to solve the above problems in the conventional technology and it is an object of the present invention to provide a speaker-embeddable seat that achieves high efficiency in reproducing low-frequency sound and provides comfort to a seated person, and a personal audio system that uses the speaker-embeddable seat.
Exemplary embodiments of the present invention are explained in detail below. The present invention is not limited to the embodiments described below. Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth.
As shown in
The mesh seat-cover 4 also covers the front surface of the backrest 3, while the sound-insulating material 5 also covers the sidepieces and the rear surface of the backrest 3. In the backrest 3, the speakers 6R and 6L that reproduce middle-to-high frequency sound are arranged near to the ears of a seated person. As described above, the ducts 20 extend up to the position below the speakers 6R and 6L, and near to the ears of the seated person. The speakers 6R and 6L are supported by an elastic material described below so that the speakers 6R and 6L are movable back and forth.
The mesh seat-cover 4 and the sound-insulating material 5 are supported by a frame 7 shown in
The frame 7 includes a pair of sidepieces 71, a pair of sidepieces 72, pipes 73a, 73b, and 73c connecting the pairs of sidepieces 71 and 72, and a pair of substantially L-shaped speaker fixing units 74 that restrict up-down movement of the speakers 6R and 6L.
As shown in
More particularly, the speakers 6R and 6L are arranged in the space surrounded by the pair of sidepieces 71, the pipe 73a, and the speaker fixing units 74. The up-down movement of the speakers 6R and 6L is restricted by the speaker fixing units 74 and the pipe 73a. The size of the speaker fixing units 74 depends on the size of speakers to be used. The sides of the speakers 6R and 6L are supported by a cushion 8 that is elastic in nature so that the speakers 6R and 6L are movable sideways. The cushion 8 is provided between the pair of sidepieces 71 of the frame 7 and the corresponding sides of the speakers 6R and 6L, and between the speaker fixing units 74 and the other corresponding sides of the speakers 6R and 6L. The front side and the rear side of the speakers 6R and 6L are supported by the cushion 8 so that the speakers 6R and 6L are movable back and forth. The cushion 8 is provided between the mesh seat-cover 4 and the front sides of the speakers 6R and 6L, and the sound-insulating material 5 and the rear sides of the speakers 6R and 6L.
When a person sits on the seat portion 2 and rests the back on the backrest 3 of the speaker-embeddable seat 1 described above, the mesh seat-cover 4 flexes, causing the cushion 8 to elastically deform. Because the positions of the speakers 6R and 6L move backward due to the elastic deformation of the cushion 8, the seated person does not come in direct contact with the speakers 6R and 6L, which makes the speaker-embeddable seat 1 comfortable to sit in.
As shown in
In the speaker-embeddable seat 1, middle-to-high frequency sound is reproduced by the speakers 6R and 6L that are arranged in the backrest 3 near to the ears of the seated person. The low-frequency vibrations output from the woofer 10 are directly transmitted to the seated person from beneath the seating surface, while the low-frequency sound output from the woofer 10 is reproduced in the backrest 3 near to the ears of the seated person via the ducts 20. That is, the low-frequency sound waves that cannot be heard by the human ear are transmitted from the woofer 10 directly to the seated person by forcing the mesh seat-cover 4 to vibrate, and the low-frequency sound waves that can be heard by the human ear are transmitted via the ducts 20 near to the ears of the seated person. The sound waves of middle-to-high frequency sound are transmitted through the mesh seat-cover 4 near to the ears of the seated person. As a result, for example, when this mechanism is used in a driver's seat, a driver alone can listen to music at loud volume or hear messages without disturbing fellow passengers. Listening to music at loud volume can help the driver shake off drowsiness while driving.
As described above, according to the first embodiment, the woofer 10 is arranged inside the seat portion 2. The ducts 20 that extend in the backrest 3 up to a position near to the ears of the seated person are connected to the woofer 10. The low-frequency sound output by the woofer 10 is transmitted via the ducts 20 to the ears of the seated person. As a result, low-frequency sound can be reproduced efficiently while a person can be seated in comfort. Because the low-frequency sound waves are effectively transmitted from the seating surface to the seated person, and the low-frequency sound waves that can be heard by the human ear are reproduced near to the ears of the seated person via the ducts 20, efficiency in reproducing low-frequency sound can be improved. Moreover, because only the hips are vibrated without the back being vibrated, the body is not subjected to over-vibration, which allows comfort for the seated person.
According to the first embodiment, because the speakers 6R and 6L for reproducing middle-to-high frequency sound are arranged near to the ears of the seated person in the backrest 3, the seated person can hear the middle-to-high frequency sound from a position near to the ears. Moreover, because the mesh seat-cover 4 covers the seating surface of the seat portion 2 and the front surface of the backrest 2[r] the backrest 3, the air and the sound can freely pass through the mesh structure. Because the sound-insulating material 5 covers the rear surface of the backrest 3, high sound insulation is achieved with less leakage of sound. Thus, the seated person can listen to a loud sound even at less volume with effective audio output.
A second embodiment of the present invention is described below with reference to
The audio processing circuit shown in
The mixer 101 mixes the received R and L signals, and outputs the mixed signals to the BPF 103. The BPF 103 removes, from the signals received from the mixer 101, frequency components of 400 Hz or above (middle-to-high frequency components) and outputs resultant signals to a woofer WF.
The BPF 102 removes, from the received R signals, frequency components of 200 HZ or less (low-frequency components), and outputs resultant signals to the delay circuit 105 and the mixer 107. The delay circuit 105 delays the R signals received from the BPF 102 by a predetermined time (for example, 5 to 10 msec) and outputs the delayed signals to a rear right speaker RR.
The BPF 104 removes, from the received L signals, frequency components of 200 HZ or less (low-frequency components), and outputs resultant signals to the delay circuit 106 and the mixer 107. The delay circuit 106 delays the L signals received from the BPF 104 by a predetermined time (for example, 5 to 10 msec) and outputs the delayed signals to a rear left speaker RL.
The mixer 107 mixes the R signals and the L signals received from the BPF 102 and the BPF 104, respectively, and outputs the mixed signals to a center front speaker CF.
According to the second embodiment, the audio signals that are to be output from the center front speaker CF, the rear right speaker RR, and the rear left speaker RL are subjected to reverberation processing and frequency characteristic conversion so that a sound image is localized anterior to the head of a person seated in the seat. Hence, a comfortable personal audio environment can be provided to the person seated in the speaker-embeddable seat 1.
A third embodiment of the present invention is described below with reference to
The audio processing circuit shown in
The mixer 201 mixes the R and L signals that are received, and outputs the mixed signals to the BPF 203. The BPF 203 removes, from the signals received from the mixer 201, frequency components of 400 Hz or above (middle-to-high frequency components) and outputs resultant signals to a woofer WF.
The BPF 202 removes, from the received R signals, frequency components of 200 HZ or less (low-frequency components), and outputs resultant signals to the delay circuit 205 and a front right speaker FR. The delay circuit 205 delays the R signals received from the BPF 202 by a predetermined time (for example, 5 to 10 msec) and outputs the delayed signals to a rear right speaker RR.
The BPF 204 removes, from the received L signals, frequency components of 200 HZ or less (low-frequency components), and outputs resultant signals to the delay circuit 206 and a front left speaker FL. The delay circuit 206 delays the L signals received from the BPF 204 by a predetermined time (for example, 5 to 10 msec) and outputs the delayed signals to a rear left speaker RL.
According to the third embodiment, the audio signals that are to be output from the front right speaker FR, the front left speaker FL, the rear right speaker RR, and the rear left speaker RL are subjected to reverberation processing and frequency characteristic conversion so that a sound image is localized anterior to the head of a person seated in the seat. Hence, a comfortable personal audio environment can be provided to the person seated in the speaker-embeddable seat 1.
A speaker-embeddable seat and a personal audio system according to the present invention are suitable for implementing in all types of seats (body-felt sound system) such as in a vehicle seat, a living-room seat, and a relaxation seat.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-098871 | Mar 2005 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2006/305050 | 3/14/2006 | WO | 00 | 9/27/2007 |
