U.S. patent application number 11/948974 was filed with the patent office on 2008-06-05 for vibro-acoustic system.
Invention is credited to Yuichi Nakajima.
Application Number | 20080129094 11/948974 |
Document ID | / |
Family ID | 39474866 |
Filed Date | 2008-06-05 |
United States Patent
Application |
20080129094 |
Kind Code |
A1 |
Nakajima; Yuichi |
June 5, 2008 |
VIBRO-ACOUSTIC SYSTEM
Abstract
The present invention is directed to providing a vibro-acoustic
system that can be used for an extended period of time by reducing
the uncomfortable feeling or sensation of pressure that a user may
experience during use. The vibro-acoustic system comprises: a seat
having a seatback and a seat proper; a band dividing circuit which
produces a first sound signal and a second sound signal by dividing
an input sound signal into frequency bands; a first vibrating
device which vibrates in accordance with the first sound signal,
and which is mounted in the seatback so that the direction of
vibration of the first vibrating device is parallel or
substantially parallel to the occupant-side surface of the
seatback; and a second vibrating device which vibrates In
accordance with the second sound signal, and which is mounted in
the seat proper so that the direction of vibration of the second
vibrating device is parallel or substantially parallel to the
occupant-side surface of the seat proper.
Inventors: |
Nakajima; Yuichi; (Kobe-shi,
JP) |
Correspondence
Address: |
CHRISTIE, PARKER & HALE, LLP
PO BOX 7068
PASADENA
CA
91109-7068
US
|
Family ID: |
39474866 |
Appl. No.: |
11/948974 |
Filed: |
November 30, 2007 |
Current U.S.
Class: |
297/217.4 |
Current CPC
Class: |
A61H 23/0236 20130101;
A61H 2201/0138 20130101; A61H 2201/0149 20130101; A61H 2203/0431
20130101; B60N 2/90 20180201; A61H 2205/081 20130101; A61H 2205/10
20130101 |
Class at
Publication: |
297/217.4 |
International
Class: |
A47C 31/00 20060101
A47C031/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 1, 2006 |
JP |
2006-325606 |
Claims
1. A vibro-acoustic system comprising: a seat having a seatback and
a seat proper; and a vibrating device which vibrates in accordance
with an applied sound signal, wherein said vibrating device is
mounted in said seat so that the direction of vibration of said
vibrating device is parallel or substantially parallel to an
occupant-side surface of said seatback or said seat proper.
2. The vibro-acoustic system according to claim 1, further
comprising a source which produces said sound signal.
3. A vibro-acoustic system comprising: a seat having a seatback and
a seat proper; a band dividing circuit which produces a first sound
signal and a second sound signal by dividing an input sound signal
into frequency bands; a first vibrating device which vibrates in
accordance with said first sound signal, and which is mounted in
said seatback so that the direction of vibration of said first
vibrating device is parallel or substantially parallel to an
occupant-side surface of said seatback; and a second vibrating
device which vibrates in accordance with said second sound signal,
and which is mounted in said seat proper so that the direction of
vibration of said second vibrating device is parallel or
substantially parallel to an occupant-side surface of said seat
proper.
4. The vibro-acoustic system according to claim 3, further
comprising a source which produces said sound signal.
5. The vibro-acoustic system according to claim 3, wherein said
first sound signal is higher in frequency than said second sound
signal.
6. The vibro-acoustic system according to claim 3, wherein said
seatback and said seat proper are each formed from a polyurethane
foam, and said first and second vibrating devices are mounted so as
to be embedded in the respective polyurethane foams.
7. The vibro-acoustic system according to claim 3, further
comprising a selecting means for selecting which of the first and
second vibrating devices is to be caused to vibrate.
Description
[0001] This application is a new U.S. patent application that
claims benefit of JP 2006-325606, filed on Dec. 1, 2006, the entire
content of JP 2006-325606 is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a vibro-acoustic system, or
more specifically to a vibro-acoustic system for mounting in a
vehicle seat.
BACKGROUND ART
[0003] A vibro-acoustic system generally known as "Bodysonic"
comprises a means for providing physically perceptible vibrations
and a speaker both mounted in a chair, a cushion, or the like, and
a user can easily experience a dynamic sensation and realistic
feeling playbacked sounds.
[0004] An apparatus is known in which such a vibro-acoustic system
is used in a vehicle seat (for example, refer to patent document
1). In the system described in patent document 1, a transducer is
mounted on a structural frame of the vehicle seat so that the
vibration of the transducer is transmitted to the occupant of the
seat via the frame.
[0005] However, with this apparatus, since the transducer vibrates
in a direction directly opposed to the direction of the occupant,
there has been the problem that the occupant, when subjected to the
vibrations for an extended period of time, may feel an unpleasant
sensation and may experience, for example, an uncomfortable feeling
or sensation of pressure. This has presented a serious problem
particularly in the case of vehicle seats where the occupants have
to stay seated for a long period of time.
[0006] Patent document 1: Japanese Utility Model Publication No.
H06-23389 (FIG. 1)
SUMMARY OF THE INVENTION
[0007] Accordingly, it is an object of the present invention to
provide a vibro-acoustic system that can solve the above
problem.
[0008] It is another object of the present invention to provide a
vibro-acoustic system that can be used for an extended period of
time by reducing an uncomfortable feeling or sensation of pressure
that the user may experience during use.
[0009] A vibro-acoustic system according to the present invention
comprises: a seat having a seatback and a seat proper; and a
vibrating device which vibrates in accordance with an applied sound
signal, wherein the vibrating device is mounted in the seat so that
the direction of vibration of the vibrating device is parallel or
substantially parallel to the occupant-side surface of the seatback
or the seat proper.
[0010] Further, a vibro-acoustic system according to the present
invention comprises: a seat having a seatback and a seat proper; a
band dividing circuit which produces a first sound signal and a
second sound signal by dividing an input sound signal into
frequency bands; a first vibrating device which vibrates in
accordance with the first sound signal, and which is mounted in the
seatback so that the direction of vibration of the first vibrating
device is parallel or substantially parallel to the occupant-side
surface of the seatback; and a second vibrating device which
vibrates in accordance with the second sound signal, and which is
mounted in the seat proper so that the direction of vibration of
the second vibrating device is parallel or substantially parallel
to the occupant-side surface of the seat proper.
[0011] Preferably, the vibro-acoustic system according to the
present invention further comprises a source which produces the
sound signal.
[0012] According to the vibro-acoustic system of the present
invention, since each vibrating device that vibrates is mounted so
that the direction of its vibration is not perpendicular to the
occupant-side surface of the seatback or the seat proper, i.e., the
direction of vibration is parallel or substantially parallel to the
surface, the system can be used for an extended period of time
without causing very much discomfort or sensation of pressure to
the occupant.
[0013] Furthermore, according to the vibro-acoustic system of the
present invention, since the sound signal from the source is
divided into frequency bands, and the vibrating devices mounted
separately in the seat are driven independently of each other, more
dynamic and realistic sensations can be provided to the user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1(a) is a diagram explaining the operation of a
vibro-acoustic system according to the present invention, and FIG.
1(b) is a diagram explaining the operation of a vibro-acoustic
system according the prior art.
[0015] FIG. 2 is a block diagram showing the general configuration
of the vibro-acoustic system 100 according to the present
invention.
[0016] FIG. 3 is a diagram showing an example in which vibrating
devices are mounted in a vehicle seat.
[0017] FIG. 4 is a diagram showing the arrangement of the vibrating
devices as viewed from the back of the vehicle seat.
[0018] FIG. 5 is a diagram showing another mounting example of the
vibrating devices.
[0019] FIG. 6 is a diagram showing still another mounting example
of the vibrating devices.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] A vibro-acoustic system according to the present invention
will be described below with reference to the drawings. However, it
should be noted that the scope of the present invention is not
limited by the specific embodiments described herein, but may be
defined by the appended claims and their equivalents.
[0021] FIG. 1 is a diagram explaining the operation of the
vibro-acoustic system according to the present invention.
[0022] FIG. 1(a) shows an example in which a vibrating device 1
used in the vibro-acoustic system of the present invention is
mounted in a seat 10, while FIG. 1(b) shows an example in which a
conventional Bodysonic-type transducer 2 and a vibrating plate 3
are mounted in the seat 10. Here, seat 10 comprises a headrest 11,
a seatback 12, and a seat proper 13.
[0023] Unlike conventional transducer 2, vibrating device 1
contains a vibrator that has an increased thickness and a
cylindrical shape and that vibrates in a direction parallel to the
longitudinal direction of the vibrating device. The vibrator is
designed so that the intensity of its vibration varies in
accordance with the sound signal applied to the vibrating device 1.
Accordingly, when a sound signal is applied to the vibrating device
1, the vibrating device vibrates in accordance with the applied
sound signal.
[0024] In FIG. 1(a), the vibrating device 1 is mounted vertically
in the seatback 12 of the seat 10. When a sound signal is applied
to the vibrating device 1, the vibrating device 1 vibrates in the
direction indicated by arrow A shown in FIG. 1(a); as a result, the
vibration propagates along the vertical direction of the seatback
12, causing the entire structure of the seatback 12 to vibrate, and
the resulting vibration is transmitted to the occupant of the seat
10. In other words, the vibrating device 1 is mounted so that the
direction of its vibration is not perpendicular to the
occupant-side surface of the seatback 12, i.e., the direction of
vibration is parallel or substantially parallel to the surface.
Accordingly, the occupant can feel very soft vibrations, and even
when the occupant stays seated for an extended period of time in
the seat 10 equipped with the vibrating device 1, the occupant does
not experience an uncomfortable feeling or a sensation of
pressure.
[0025] In FIG. 1(b), the transducer 2 causes the vibrating plate 3
to vibrate, and the vibration of the vibrating plate 3 directly
strikes the occupant's back; this structure can easily produce
strong vibrations, but when subjected to vibrations for an extended
period of time, the occupant may have an uncomfortable feeling or a
sensation of pressure. In other words, the conventional transducer
2 is mounted so that the direction of its vibration (the direction
indicated by arrow B) is perpendicular to the occupant-side surface
of the seatback 12.
[0026] In this way, according to the vibro-acoustic system of the
present invention, since the vibrating device 1 is mounted so that
the direction of its vibration is not perpendicular to the
occupant-side surface of the seatback 12 (or the seat proper 13)
but is parallel or substantially parallel to the surface, the
vibrations do not directly strike the occupant's back, and the
occupant does not experience an uncomfortable feeling or a
sensation of pressure even when the occupant stays seated for an
extended period of time.
[0027] FIG. 2 is a block diagram showing the general configuration
of the vibro-acoustic system 100 according to the present
invention.
[0028] The vibro-acoustic system 100 comprises a source 110, a
waveform extracting circuit 120, an FFT circuit 130, a band
dividing circuit 140, an amplifying unit 150, and vibrating devices
160 to 169.
[0029] The source 110 which produces a sound signal may be one or a
plurality of sources selected from among a CD/MD playback unit, a
radio receiver unit, a TV receiver unit, a DVD playback unit, an HD
(Hard Disk) playback unit, and a navigation unit.
[0030] The waveform extracting circuit 120 extracts the waveform of
the sound signal output from the source 110, the FFT circuit 130
extracts the sound signal for each frequency band, and the band
dividing circuit 140 divides the sound signal into three
predetermined bands, i.e., the first mid-to-low frequency band (150
to 200 Hz), the second mid-to-low frequency band (100 to 150 Hz),
and the low frequency band (50 to 100 Hz), for output to the
amplifier circuit 150.
[0031] The band dividing circuit 140 distributes the sound signal
in the first mid-to-low frequency band (150 to 200 Hz) to a first
vibrating device group consisting of the vibrating devices 160 and
161, the sound signal in the second mid-to-low frequency band (100
to 150 Hz) to a second vibrating device group consisting of the
vibrating devices 162 and 163, and the sound signal in the low
frequency band (50 to 100 Hz) to a third vibrating device group
consisting of the vibrating devices 164 to 169. Each of the
vibrating devices 160 to 169 used here is identical to the
vibrating device 1 described with reference to FIG. 1(a).
[0032] The amplifier circuit 150, which is paired with the
vibrating devices 160 to 169, amplifies the sound signals output
from the band dividing circuit 140 and outputs them to the
respective vibrating devices.
[0033] Though not shown in FIG. 2, the vibro-acoustic system 100
includes a plurality of speakers for reproducing sound signals
higher than the first mid-to-low frequency band signal (150 to 200
Hz). It will also be noted that the vibro-acoustic system 100 need
not necessarily include the source 110 and/or the vibrating devices
160 to 169.
[0034] FIG. 3 is a diagram showing an example in which the
vibrating devices are mounted in a vehicle seat.
[0035] As shown in FIG. 3, the vibrating devices 160 and 161 of the
first vibrating device group are mounted in the upper half of the
seatback 12 at positions spaced apart from the centerline A of the
seatback 12, the vibrating devices 162 and 163 of the second
vibrating device group are mounted in the lower half of the
seatback 12 at positions spaced apart from the centerline A of the
seatback 12, the vibrating devices 164 to 167 of the third
vibrating device group are mounted in the seat proper 13 at
positions spaced apart from the centerline A of the seat proper 13,
and the vibrating devices 168 and 169 of the third vibrating device
group are mounted in the forward end portion of the seat proper 13.
All of the vibrating devices are mounted by avoiding the positions
where the occupant's back or buttocks directly contact the seatback
12 or the seat proper 13 when the occupant is seated in the seat
10.
[0036] FIG. 4 is a diagram showing the arrangement of the vibrating
devices as viewed from the back of the vehicle seat.
[0037] As shown in FIG. 4, the vibrating devices 160 to 163 are
mounted so as to be embedded in a polyurethane foam 15 which is a
seat material supported by such means as springs and the seat frame
14 of the seat 10. Preferably, the vibrating devices are mounted by
first forming recesses each slightly smaller than each vibrating
device in the polyurethane foam 15 and then pushing the vibrating
devices into the respective recesses in the polyurethane foam,
because the vibrations from the vibrating devices can then be
transmitted effectively to the seat. Since the recent trend is to
reduce the thickness of the vehicle seat 10, embedding the
vibrating devices in polyurethane foam is also preferable from the
standpoint of securing space for mounting the vibrating
devices.
[0038] The hardness of the polyurethane form is in the range of 10
to 350 N, which is sufficient to transmit the vibrations of the
vibrating devices. Here, either rigid urethane or soft urethane may
be used as long as it is foamed urethane.
[0039] Though not shown in FIG. 4, the vibrating devices 164 to 169
mounted in the seat proper 13 are likewise embedded in the
polyurethane foam of the seat proper 13.
[0040] Next, the operation of the vibro-acoustic system 100 will be
described.
[0041] Referring to the configuration shown in FIG. 2, the sound
signal input from the source 110 is divided into three frequency
bands, the first mid-to-low frequency band (150 to 200 Hz), the
second mid-to-low frequency band (100 to 150 Hz), and the low
frequency band (50 to 100 Hz), and the sound signals of the
respective frequency bands are distributed to the first to third
vibrating device groups, respectively. The vibrating devices of the
first to third vibrating device groups vibrate in accordance with
the applied sound signals, and vibrations providing a dynamic
sensation and a realistic feeling can thus be transmitted to the
occupant of the seat 10. As earlier described, all of the vibrating
devices 160 to 169 are mounted by avoiding positions where the
occupant's back or buttocks directly contact the seatback 12 or the
seat proper 13 when the occupant is seated in the seat 10. As a
result, the vibrations can be transmitted indirectly to the
occupant, reducing the possibility of giving the occupant an
uncomfortable feeling or a sensation of pressure even when the
system is used for an extended period of time.
[0042] The reason that the vibrating devices corresponding to the
first mid-to-low frequency band (150 to 200 Hz) are mounted in the
upper half of the seatback 12 while the vibrating devices
corresponding to the low frequency band (50 to 100 Hz) are mounted
in the seat proper 13 is that the human body is sensitive to
low-frequency vibrations applied from under the body.
[0043] In the above description, it should be noted that the number
and the arrangement of the vibrating devices and the classification
of the first mid-to-low frequency band, the second mid-to-low
frequency band, and the low frequency band are only examples and
may be changed appropriately to suit the shape and material of the
seat, the shape of the vehicle compartment, etc.
[0044] Further, in the above description, three sound signals have
been created by dividing the sound signal from the source 110 into
three frequency bands, and the vibrating devices of the first to
third vibrating device groups have been caused to vibrate
simultaneously in accordance with the respective sound signals.
Alternatively, control may be performed so that when the sound
signal from the source 110 is rich in frequency components falling
within the first mid-to-low frequency band (150 to 200 Hz), only
the vibrating devices 160 and 161 of the first vibrating device
group are caused to vibrate, but when the sound signal is rich in
frequency components falling within the second mid-to-low frequency
band (100 to 150 Hz), only the vibrating devices 162 and 163 of the
second vibrating device group are caused to vibrate, while on the
other hand, when the sound signal is rich in frequency components
falling within the low frequency band (50 to 100 Hz), only the
vibrating devices 164 to 169 of the third vibrating device group
are caused to vibrate. Control for the above mode switching is
performed by the band dividing circuit 40.
[0045] Further, a selector switch for allowing the occupant to
select which of the first to third vibrating device groups is to be
caused to vibrate may be provided on or near the seat 10 so that
the mode switching by the band dividing circuit 40 can be
controlled in accordance with the setting of the selector
switch.
[0046] FIG. 5 is a diagram showing another mounting example of the
vibrating devices.
[0047] In the example of FIG. 5, two vibrating devices 170 and 171
are mounted only in the center portion of the seatback 12 of the
seat 10 by arranging the vibrating devices along a direction
perpendicular to the longitudinal direction of the seatback 12. In
this case also, the vibrating devices 170 and 171 are mounted to
avoid positions that directly contact the occupant's back when the
occupant is seated in the seat 10. Further, since each of the
vibrating devices 170 and 171 is mounted so that the direction of
its vibration is parallel or substantially parallel to the
occupant-side surface of the seatback 12, the vibration can be
transmitted indirectly to the occupant, reducing the possibility of
giving the occupant an uncomfortable feeling or a sensation of
pressure even when the system is used for an extended period of
time.
[0048] In the case of FIG. 5, the vibrating devices 170 and 171 are
driven by the sound signal representing the entire frequency range
(200 to 50 Hz)
[0049] FIG. 6 is a diagram showing still another mounting example
of the vibrating devices.
[0050] In the example of FIG. 6, two vibrating devices 180 and 181
are mounted only in the center portion of the seatback of the seat
10 by arranging the vibrating devices along a direction parallel to
the longitudinal direction of the seatback 12. In this case, the
vibrating devices 180 and 181 are mounted to avoid positions that
directly contact the occupant's back when the occupant is seated in
the seat 10. Further, since each of the vibrating devices 180 and
181 is mounted so that the direction of its vibration is parallel
or substantially parallel to the occupant-side surface of the
seatback 12, the vibration can be transmitted indirectly to the
occupant, reducing the possibility of giving the occupant an
uncomfortable feeling or a sensation of pressure even when the
system is used for an extended period of time.
[0051] In the case of FIG. 6, the vibrating devices 180 and 181 are
driven by the sound signal representing the entire frequency range
(200 to 50 Hz).
* * * * *