EP2136572B1

EP2136572B1 - Speaker

Info

Publication number: EP2136572B1
Application number: EP09007888A
Authority: EP
Inventors: Shin Ito
Original assignee: Yamaha Corp
Current assignee: Yamaha Corp
Priority date: 2008-06-19
Filing date: 2009-06-16
Publication date: 2011-08-17
Anticipated expiration: 2029-06-16
Also published as: EP2136572A1; CN101610441B; CN101610441A; JP2010004207A; JP5309713B2; ATE521196T1

Abstract

In a speaker set having an enclosure containing a drive unit, a flying bridge is arranged to interconnect inner walls of the enclosure. The flying bridge is formed with a recess at location excluding a portion abutting the inner walls, and a damping material is fitted in the recess for absorbing vibration of the enclosure. Typically, the flying bridge interconnects opposite ones of the inner walls of the enclosure. The flying bridge is composed of a plurality of wedge-shaped parts contacting each other at planes oblique to the inner walls interconnected by the flying bridge, and the wedge-shaped parts are arranged such that a front end of one wedge-shaped part is directed opposite to a front end of another wedge-shaped part which is adjacent to the one wedge-shaped part.

Description

BACKGROUND OF THE INVENTION

[Technical Field of the Invention]

The present invention relates to a speaker having a structure to control vibration generated from an enclosure as a result of vibration generated from a speaker drive unit.

[Description of the Related Art]

In a conventional speaker, a speaker drive unit vibrates during emission of sound, and the vibration is transmitted from the speaker drive unit to an enclosure. As a result, the enclosure vibrates. Consequently, enclosure reverberation occurs, and therefore, noise is generated, with the result that sound quality is deteriorated. For this reason, a speaker capable of reducing vibration generated from an enclosure has been proposed (for example, see Japanese Patent Application Publication No. 2000-125380 ).
For example, Japanese Patent Application Publication No. 2000-125380 discloses a speaker box using a composite material, such as medium density fiberboard (MDF), wherein damping sheets are applied to walls of an enclosure.
However, the device of Japanese Patent Application Publication No. 2000-125380 has a problem in that it is not possible to completely control vibration generated from the main body of the speaker box although the vibration is reduced. Also, the composite material used to constitute each wall of the enclosure is expensive. Furthermore, it is necessary to select the quality of the composite material through trial and error to obtain optimal effects, which is time-consuming.
US-A-5,170,436 discloses an acoustic loudspeaker cabinet enclosure which has a woofer and a tweeter mounted on a front wall and a tuned port with a duct extending into the interior of the cabinet. A pair of tuned baffles are mounted within the cabinet, one of the baffles being secured to the rear wall within the peripheral envelope of the woofer and the other of the baffles being secured to the front wall approximately half way between the position of the duct and the woofer. The baffles have a plurality of reed fingers which are excited at predetermined frequencies to resonant thereby resulting in a controlled resonance developed by the air within the cabinet to provide a bass response more transient than that of conventional speaker systems, and a smoother, deeper, more natural response. The tuned baffles within the cabinet act to provide an internal tuning port within the cabinet similar to the conventional external tuning port. In the preferred embodiment the port and duct are positioned in the rear wall. A much smaller woofer may be used than in conventional systems, so the woofer may be utilized for producing the mid-range frequencies.
US-A-4,690,244 discloses a loudspeaker enclosure which comprises a rectangular box-like housing consisting of top and bottom walls, front and back walls, left and right side walls, each of the walls being formed by a wooden panel, a hollow stiffening structure located within the housing and extending from the top wall to the bottom wall, from the front wall to the back wall, and from the left side wall to the right side wall, the hollow stiffening structure comprising a first set of spaced-apart stiffening panels arranged with their planes substantially parallel to each other and substantially parallel to the walls of a pair of opposed housing walls, and a second set of spaced-apart stiffening panels arranged with their planes substantially parallel to each other and substantially parallel to the walls of a different pair of opposed housing walls, the stiffening panels of the first set being secured to stiffening panels of the second set and intersecting the substantially orthogonally so that the stiffening panels, together with the housing walls define a multiplicity of rectangular parallelepipedal cells, holes being provided in the stiffening panels to provide communication between adjacent cells.
JP 55-088496 A discloses a speaker system. In order to prevent vibration of the speaker cabinet as well as to absorb the steady waves by sticking the figurate foaming elastic component containing bituminous material on the inner surface of the cabinet composed of the hard material such as the metal or the like, both the woofer and the tweeter are attached to cabinet made of the metal such as the aluminum die casting alloy, and figurate foaming elastic components containing bituminous material and cut into sheet forms are provided on the inner surface of cabinet. The components are located most effectively in the L-shape from the top to back of cabinet and in the U-shape from the lower parts of both sides to the lower part of the back and enclosing woofer respectively.

SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide a speaker wherein vibration generated from an enclosure is effectively controlled.
This object is achieved according to the present invention by a speaker as set forth in claim 1. Preferred embodiments of the present invention may be gathered from the dependent claims.
The speaker according to the present invention interconnects inner walls of the enclosure using a connecting part. Also, the connecting part has a cutout formed at location excluding portions abutting the inner walls. Furthermore, a damping material is fitted in the cutout. Consequently, the connecting part having the cutout formed therein interconnects the inner walls of the enclosure and, in addition, serves as an elastic body. The damping material fitted in the cutout absorbs vibration transmitted to the connecting part. Although vibration generated from a speaker drive unit is transmitted to the enclosure, the connecting part absorbs the vibration of the enclosure, thereby controlling the vibration of the enclosure. As a result, it is possible to control noise caused by the vibration generated from the enclosure. Also, since the connecting part is constructed such that the cutout is formed in the connecting part, and the damping material is fitted in the cutout, it is possible to prepare the connecting part inexpensively and easily.
Also, the speaker according to the present invention may be constructed such that the connecting part interconnects opposite ones of the inner walls of the enclosure. Consequently, it is possible for the opposite inner walls not to vibrate.
Furthermore, the speaker according to the present invention may be constructed such that the connecting part interconnects portions of the inner walls which would develop a maximum amplitude of the vibration under a free state. Typically, the connecting part interconnects appropriate centers of two inner walls which are maximally movable area. Consequently, the connecting part is connected to the positions having the maximum amplitude, and therefore, it is possible to most effectively control vibration generated from the enclosure.
In addition, the speaker according to the present invention may be constructed such that the connecting part comprises a plurality of wedge-shaped parts contacting each other at planes not parallel to the inner walls interconnected by the connecting part, and the wedge-shaped parts are arranged such that a front end of one wedge-shaped part is directed opposite to a front end of another wedge-shaped part which is adjacent to the one wedge-shaped part.
In one form (as shown in fig. 6), the plurality of the wedge-shaped parts comprise a pair of the wedge-shaped parts, wherein one of the wedge-shaped parts is formed with the cutout and the damping material is fitted in the cutout, while the other wedge-shaped part is not formed with a cutout nor does have a damping material.
For example, in a structure in which the connecting part includes two wedge-shaped parts A and B, the respective parts may be disposed and fixed to the inner walls of the enclosure as follows. First, the front end of the part A is directed to the front of the enclosure, and one face of the part A is directly fixed to the middle of the inner wall of the left-side face of the enclosure. Subsequently, the front end of the part B is directed to the rear of the enclosure, and one face of the part B is brought into contact with the middle of the inner wall of the right-side face of the enclosure. Subsequently, the parts A and B are disposed such that planes of the parts A and B oblique to the inner wall faces of the enclosure come into contact with each other. Subsequently, the respective parts are slid until the inner walls of the enclosure are interconnected by the respective parts. Consequently, it is possible to install the respective parts of the connecting part in the enclosure without adjusting the size (width) of the connecting part based on the distance between the opposite inner walls of the enclosure, thereby achieving easy preparation of the connecting part without the necessity to precisely adjust the size of the connecting part to suit various enclosures.
Also, the speaker according to the present invention may be constructed such that the connecting part interconnects neighboring ones of the inner walls of the enclosure. In this structure, it is possible for the connecting part to interconnect the neighboring inner walls of the enclosure, for example, even when the opposite inner walls of the enclosure cannot be interconnected due to the presence of the speaker drive unit or the like, and therefore, it is possible for the enclosure not to vibrate.
Furthermore, the speaker according to the present invention may be constructed such that the damping material is fitted in the cutout in a contracted state. Consequently, the damping material is kept contracted by the cutout, and therefore, it is possible to retain the damping material in the cutout without adhesion.
According to the present invention, it is possible for the speaker to reliably control vibration generated from the enclosure, thereby improving sound quality without deterioration of sound quality due to noise caused by the vibration generated from the enclosure. Also, it is possible to control noise caused by the vibration generated from the enclosure inexpensively and easily.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view illustrating a connecting part according to a first embodiment of the present invention.
FIG. 2 is a view illustrating a process of installing the connecting part.
FIG. 3 is a conceptual view illustrating vibration generated from an enclosure of a speaker.
FIG. 4 is a see-through perspective view illustrating the enclosure in which the installation of the connecting part is completed.
FIG. 5 is a front view illustrating another example of the connecting part according to the first embodiment of the present invention.
FIG. 6 is a front view illustrating a further example of the connecting part according to the first embodiment of the present invention.
FIG. 7 is a schematic view illustrating a connecting part according to a second embodiment of the present invention.
FIG. 8 is a see-through perspective view illustrating an enclosure in which the installation of the connecting part is completed.

DETAILED DESCRIPTION OF THE INVENTION

[First embodiment]

A speaker according to a first embodiment of the present invention will be described hereinafter with reference to FIGS. 1 to 4. FIG. 1 is a view illustrating a connecting part according to the first embodiment of the present invention. FIG. 1(A) is a front view showing wood which is a material for a connecting part, and FIG. 1(B) is a front view schematically showing the connecting part. FIG. 2 is a view illustrating a process of installing the connecting part. FIG. 2(A) is a see-through plan view showing the interior of an enclosure of the speaker before the installation of the connecting part, and FIG. 2(B) is a see-through plan view showing the interior of the enclosure after the installation of the connecting part. FIG. 3 is a conceptional view illustrating vibration generated from an enclosure of a speaker. FIG. 4 is a see-through perspective view illustrating the enclosure in which the installation of the connecting part is completed. FIG. 4(A) shows the installation of a single connecting part, and FIG. 4(B) shows the installation of multiple connecting parts.
First, the shape of a connecting part 3 installed in an enclosure 2 (See FIG. 2) of the speaker 1a and an example of a method of preparing the connecting part 3 will be described. As shown in FIG. 1(A), the connecting part 3 is formed of rectangular parallelepiped wood 5 having a predetermined thickness. The wood 5 may be medium density fiberboard (MDF) or other inexpensive materials. The connecting part 3 is composed of a pair of parts 3a and 3b obtained by cutting the rectangular parallelepiped wood 5 along a straight line L passing through an appropriate center O of the rectangular parallelepiped wood 5. At this time, the oblique line L is not parallel to the respective sides of the wood 5. The parts 3a and 3b of the connecting part 3 are formed in the shape of a right angle trapezoid, the section of which is an oblique side. However, the shape of the parts 3a and 3b are not limited to the right angle trapezoid. For example, the parts 3a and 3b may be formed in the shape of a wedge. The parts 3a and 3b may also be formed in the shape of a triangle. When the parts 3a and 3b are formed in the triangular shape, however, acute-angle portions of the parts 3a and 3b may have low strength. Consequently, it is necessary to pay attention to this point when installing the connecting part 3.
As shown in FIG. 1(B), each of the parts 3a and 3b is provided with a cutout 30, which is formed by cutting each of the parts 3a and 3b from an appropriate middle of one of the edges extending from the section 31, e.g., a long edge 33, toward an appropriate middle of the other of the edges extending from the section 31, e.g., a short edge 34. It is preferable for each cutout 30 to have a uniform width. In each cutout 30 is fitted a damping material 4, which is located at the edge face 33 side. Each damping material 4 may have a free thickness greater than the width of each cutout 30 and a length equivalent to about half that of each cutout 30. Preferably, each damping material 4 is a material having small temporal change and small compression distortion. Specifically, each damping material 4 may be high-density urethane foam.
Since the inexpensive wood 5 is cut, and the cutouts 30, in which the respective damping materials 4 are fitted, are formed in the respective divided parts of the wood 5, as described above, it is possible to prepare the connecting part 3 easily and inexpensively. Also, since the damping materials 4, the thickness of which is greater than the width of the cutouts 30, are fitted in the respective cutouts 30, it is possible to easily fix the damping materials 4 in the respective cutouts 30 by pressing the damping materials 4.
Next, a process of installing the connecting part 3 in the enclosure 2 of the speaker 1a will be described. First, as shown in FIG. 2(A), the part 3a is disposed such that a side face 32 of the part 3a comes into contact with the inner wall of a left-side face 23 of the enclosure 2. Subsequently, the part 3b is disposed such that a side face 32 of the part 3b is parallel to the inner wall of a right-side face 22 of the enclosure 2 and such that the section 31 of the part 3b comes into contact with the section 31 of the part 3a. Afterwards, the part 3b is moved along the slant section 31 of the part 3a in the direction indicated by an arrow 7. When the side face 32 of the part 3b comes into contact with the inner wall of the enclosure 2, the parts 3a and 3b push against the opposite side faces 22 and 23 of the enclosure to a certain extent, as shown in FIG. 2(B), the movement of the part 3b is stopped. When the installation of the connecting part 3 is completed as described above, it is possible to securely interconnect the opposite inner walls of the enclosure by the connecting part 3.
When the connecting part 3 is installed as described above, vibration generated from the opposite side faces 22 and 23 of the enclosure 2 is transmitted to the connecting part 3 (the parts 3a and 3b), and the cutouts 30, running appropriately parallel to the faces 32, expand and contract in response to the vibration. That is, the cutouts 30 serve as an elastic body. Also, the damping materials 4 fitted in the respective cutouts 30 absorb and convert the expansion and contraction (vibration) energy into thermal energy, which is dissipated to the outside.
Consequently, it is possible for the connecting part 3 to absorb vibration generated from the opposite inner walls of the enclosure 2. Also, since the connecting part 3 is constituted by the wedge-shaped parts, it is possible to easily install the connecting part 3 to the inner walls of the enclosure 2.
Also, as described above, it is possible to adjust the size of the connecting part 3 (the distance between the side face 32 of the part 3a and the side face 32 of the part 3b) only by moving the part 3b along the slant section 31 of the part 3a. Consequently, even when the distance between the opposite inner walls of the enclosure 2 varies to some extent due to an error or allowance during the manufacture of the enclosure 2, it is possible for the connecting part 3 to reliably interconnect the opposite inner walls of the enclosure 2. For this reason, it is not necessary to precisely measure the distance between the inner walls of the speaker 1a, during the preparation of the connecting part 3, whereby it is possible to easily produce the connecting part 3.
Hereinafter, vibration generated from the enclosure 2 of the speaker 1a will be described. On the assumption that an installation face 21 of the speaker 1a, where a speaker drive unit 20 is mounted, having a large height to width ratio, is set as the front of the speaker 1a as shown in FIG. 3, side faces 22 and 23 of the speaker 1a have the maximum area. For this reason, the central parts of the side faces 22 and 23 of the speaker 1a maximally vibrate under a free state, and therefore the central portions of the side faces 22 and 23 of the speaker 1a develops the maximum amplitude of the vibration.
The connecting part 3 is installed, as shown in FIG. 4(A), such that portions having the maximum amplitude corresponding to approximate centers of the inner walls of the side faces 22 and 23 (the wall faces having the maximum area) of the speaker 1a are connected to each other. As a result, it is possible for the connecting part 3 to more effectively absorb vibration generated from the enclosure 2. One or more connecting parts 3 may be installed. As shown in FIG. 4(B), it is preferable to install a plurality of connecting parts 3 since such a plurality of connecting parts absorb vibration generated from the enclosure 2 more effectively than only one connecting part.
In the above construction, the connecting part 3 according to the first embodiment of the present invention is prepared such that the opposite sides (the side face 32 of the part 3a and the side face 32 of the part 3b, the faces 33 and 34 of the parts 3a and 3b) are parallel to each other. However, the side faces 33 and 34 of the parts 3a and 3b, which do not contact the enclosure 2, may not be parallel to each other.
Also, the parts 3a and 3b of the connecting part 3 according to the first embodiment of the present invention is explained as being installed to push against the opposite side faces 22 and 23 of the enclosure 2, to which, however, the present invention is not limited. For example, it may be possible to fix the respective parts of the connecting part 3 to the opposite side faces of the enclosure 2 using an adhesive to interconnect the opposite side faces of the enclosure 2. When using screws, the connecting part 3 may by installed such that the opposite side faces 22 and 23 of the enclosure 2 are pulled toward each other.
FIG. 5 is a front view illustrating another example of the connecting part according to the first embodiment of the present invention. In the previous example of the first embodiment, the connecting part 3 is explained as being constituted by the two parts, to which, however, the present invention is not limited. For example, the connecting part may include three or more of wedge-shaped parts. A connecting part 3' shown in FIG. 5(A) includes a plurality of parts 3a' to 3c' formed by cutting the wood 5 along oblique straight lines not parallel to the respective sides constituting the outer circumference of the wood 5. In each part is formed a cutout 30', in which a damping material 4 is fitted. In this structure, the respective parts may come into contact with one another at planes not parallel to the inner wall faces of the enclosure, and wedge-shaped front ends of the respective parts may be disposed in directions opposite to the directions in which the wedge-shaped front ends of the neighboring parts are disposed. Consequently, it is possible to reliably connect the connecting part to the opposite inner walls of the enclosure 2 and to control the vibration generated from the enclosure 2.
Alternatively, as shown in FIG. 5(B), a connecting part 3" may comprise a single part. In this case, the connecting part 3" is fixed to the opposite side faces of the enclosure 2 by screws such that the opposite side faces of the enclosure 2 are interconnected to each other by the connecting part 3".
Also, FIG. 6 is a front view illustrating a further example of the connecting part according to the first embodiment of the present invention. In the previous examples of the first embodiment, the cutout 30 is explained as being formed in each part of the connecting part, to which, however, the present invention is not limited. For example, a cutout 30''' may be formed in some of the parts of the connecting part. A connecting part 3"' shown in FIG. 6 includes a plurality of parts 3a"' and 3b"' formed by cutting the wood 5 along a straight line not parallel to the respective sides constituting the outer circumference of the wood 5. In the part 3b"' is formed a cutout 30''', in which a damping material 4 is fitted.
As described above, it is possible to prepare the connecting part 3 inexpensively and easily. Also, the connecting part 3 absorbs vibration generated from the enclosure 2. As a result, it is possible to control vibration generated from the enclosure 2. Consequently, it is possible for the connecting part 3 to control noise caused by vibration generated at the enclosure 2 inexpensively and easily.

[Second embodiment]

A speaker according to a second embodiment of the present invention will be described hereinafter with reference to FIGS. 7 and 8. FIG. 7 is a schematic view illustrating a connecting part according to a second embodiment of the present invention. FIG. 7(A) is a front view showing wood which is a material for a connecting part, and FIG. 7(B) is a front view schematically showing the connecting part. FIG. 8 is a see-through perspective view illustrating an enclosure in which the installation of the connecting part is completed. The second embodiment is different from the first embodiment in the shape of a connecting part 6 and in the connection between neighboring inner walls of an enclosure 2 using the connecting part 6. Therefore, only the differences of the second embodiment from the first embodiment will be described hereinafter.
First, the shape of connecting parts 6 installed in an enclosure 2 of a speaker 1b and a method of preparing the connecting parts 6 will be described. As shown in FIG. 7(A), the connecting parts 6 are prepared by cutting a rectangular parallelepiped wood 5 along a straight line L passing through an appropriate center O of the rectangular parallelepiped wood 5. Consequently, the connecting parts 6 are formed in the shape of a right angle trapezoid, to which, however, the present invention is not limited.
As shown in FIG. 7(B), the connecting part 6 is provided with a cutout 60, which is formed by cutting the connecting part 6 from an appropriate middle of a section 61 of the wood 5 toward a corner A (a corner between a side face 62 and a side face 63). In the cutout 60 is fitted a damping material 4, which is located at the section 61 side, in the same manner as in parts 3a and 3b of the connecting part 3. The damping material 4 has a thickness greater than the width of the cutout 60. Consequently, the damping material 4 is fitted in the cutout 60 in a contracted state. Since the inexpensive wood 5 is cut, and the cutout 60, in which the damping material 4 is fitted, is formed in each divided part of the wood 5, as described above, it is possible to prepare the connecting parts 6 easily and inexpensively.
Next, a process of installing the connecting parts 6 in the enclosure 2 of the speaker 1b will be described. First, as shown in FIG. 8(A), the connecting parts 6 are installed such that the connecting parts 6 interconnect the neighboring inner walls of the enclosure 2. At this time, the connecting parts 6 are fixed to the neighboring inner walls of the enclosure 2 by an adhesive such that the side faces 62 and 63 of the respective connecting parts 6 come into contact with the neighboring inner walls of the enclosure 2.
When the connecting parts 6 are installed as described above, vibration generated from the neighboring inner walls of the enclosure 2 is transmitted to the connecting parts 6, and the cutouts 60 expand and contract in response to the vibration. That is, the cutouts 60 serve as an elastic body. Also, the damping materials 4 fitted in the respective cutouts 60 absorb and convert the expansion and contraction (vibration) energy into thermal energy, which is dissipated to the outside.
In particular, a portion having the maximum amplitude corresponding to an approximate center of the inner wall of the right-side face 22 (the wall face having the maximum area) of the enclosure 2 may be connected to the inner wall of one of an installation face 21, a bottom face 24, a top face 25, or a rear face 26 neighboring to the right-side face 22. In the same manner, a portion having the maximum amplitude corresponding to an approximate center of the inner wall of the left-side face 23 of the enclosure 2 may be connected to the inner wall of one of the installation face 21, the bottom face 24, the top face 25, or the rear face 26 neighboring to the left-side face 22. Consequently, it is possible for the connecting parts 6 to absorb vibration generated from the portions having the maximum amplitude, thereby effectively absorbing vibration generated from the enclosure 2.
Also, the amplitude increases to such an extent that the distance between opposite pairs of sides 221 to 224 forming the right-side face 22 of the enclosure 2 (the distance between the long side 221 and the long side 223, the distance between the short side 222 and the short side 224) increases. For this reason, it is preferable to install the connecting part 6 such that the corner A of the connecting part 6 comes into contact with the middle of the short side 222 (or the short side 224) of the right-side face 22, not the long sides 221 and 223 of the right-side face 22. That is, it is preferable to interconnect the right-side face 22 and the bottom face 24 (or the top face 25) by interconnecting the right-side face 22 and the rear face 25 (or the installation face 21). In the same manner, it is preferable to install the connecting part 6 such that the corner A of the connecting part 6 comes into contact with the middle of a short side 232 (or a short side 234) forming the left-side face 23 of the enclosure 2, not long sides 231 and 233 forming the left-side face 23. Consequently, it is possible for the connecting part 6 to effectively absorb vibration generated from the portion having the maximum amplitude, thereby effectively absorbing vibration generated from the enclosure 2.
Consequently, it is possible for the connecting part 6 to absorb vibration generated from the neighboring inner walls (the inner wall of the side face 22 and the inner wall of the bottom face 24) of the enclosure 2. Also, it is possible to easily fix the connecting part 6 to the inner walls of the enclosure 2.
Also, each connecting part 6 is installed in the enclosure 2 such that the face 62 having an obtuse-angle front end comes into contact with the portion having the maximum amplitude, and the face 63 having an acute-angle front end comes into contact with the neighboring inner wall. That is, since the high-strength side of each connecting part 6 is fixed to the side having large amplitude, it is possible to more securely connect the neighboring inner wall to the side having large amplitude.
Furthermore, the number of the connecting parts 6 is not particularly restricted. As shown in FIG. 8(B), it is preferable to install a plurality of connecting parts 6 since the plurality of connecting parts absorb vibration generated from the enclosure 2 more effectively than only one connecting part. In particular, the installation face 21 is prepared more rigidly than other wall faces, since the speaker drive unit 20 is fixed to the installation face 21, with the result that the installation face 21 is highly resistant to vibration. For this reason, it is possible to more effectively control vibration generated from the enclosure 2 by interconnecting any one (the bottom face 24, the top face 25, or the rear face 26) of the remaining faces excluding the installation face 21 and the side face 22 or the side face 23 via the connecting part 6.
In the second embodiment of the present invention, the corner A is formed to have a right angle. However, when the connecting part is installed in the enclosure 2, it is enough for the corner A to come into contact with the inner walls of the enclosure 2. Consequently, the corner A may not have an exactly right angle.
As described above, it is possible to prepare the connecting part 6 inexpensively and easily. Also, the connecting part 6 absorbs vibration generated from the enclosure 2. As a result, it is possible for the connecting part 6 to control vibration generated from the enclosure 2. Consequently, it is possible to control noise caused by vibration generated from the enclosure 2 inexpensively and easily.
Furthermore, the shape of the connecting part is not limited to the above-described embodiments of the present invention as long as the cutout, in which the damping material 4 is fitted, is formed in the connecting part, and it is possible to interconnect the inner walls of the enclosure 2 by the connecting part. Also, the number of cutouts formed in each connecting part is not particularly restricted although only one cutout is formed in each part of the connecting part in the above-described embodiments of the present invention. For example, a plurality of cutouts may be formed in each part of the connecting part.

Claims

A speaker comprising:
a speaker drive unit (20);

an enclosure (2) that encloses the speaker drive unit (20) ; and

a connection part (3, 6) that connects two inner walls (21, 22, 23, 24, 25, 26) of the enclosure (2),

characterized in that

the connection part (3, 6) has at least one cutout (30) at a free side not connected to said inner walls (21, 22, 23, 24, 25, 26), wherein the cutout (30) is filled along at least a portion of the length of the cutout with damping material (4) for absorbing vibration of the enclosure (2) .
The speaker according to claim 1, wherein the connection part (3) connects two opposite inner walls (21, 22, 23, 24, 25, 25, 26) of the enclosure (2).
The speaker according to claim 2, wherein the connection part (3) is comprised of at least two parts (3a, 3b; 3a', 3b', 3c'; 3a'", 3b'"), a first part (3a) being connected to one inner wall (21, 22, 23, 24, 25, 26) and being provided with a first contact edge (31) on an opposite side thereto, and a second part (3b) connected to an opposite inner wall (21, 22, 23, 24, 25, 26) and being provided with a second contact edge (31) on an opposite side thereto, wherein the first and second contact edges (31) contact each other under an angle not parallel to the inner walls (21, 22, 23, 24, 25, 26) of the enclosure (2), wherein at least one of said parts (3a, 3b; 3a', 3b', 3c'; 3b"') has at least one cutout (30) in one of its free sides.
A speaker according to claim 3, wherein each of said parts (3a, 3b; 3a', 3b', 3c') has at least one cutout (30) in one of its free sides.
A speaker according to any of the preceding claims, wherein the connection part (3) connects two inner walls (21, 22, 23, 24, 25, 26) of said enclosure (2) at a position where the respective inner walls (21, 22, 23, 24, 25, 26) develop a maximum amplitude of vibration in a free swinging state without said connection part (3).
The speaker according to claim 1, wherein the connection part (6) connects two neighboring inner walls (21, 22, 23, 24, 25, 26) of the enclosure (2).
The speaker according to any of the preceding claims, wherein the damping material (4) is fitted in the cutout (30) in a compressed state.
The speaker according to any of the preceding claims, wherein the damping material (4) fills up about one half of the cutout (30), extending from the side of the connection part (3, 6) inwardly.
The speaker according to any of the preceding claims, wherein the damping material (4) is high-density urethane foam.
The speaker according to any of the preceding claims, wherein said cutout (30) extends from approximately the middle of said free side into a direction approximately towards the middle of an opposite side.