JP5382020B2 - Speaker - Google Patents

Description

  The present invention relates to a speaker.

  With the advent of high sound quality digital content such as DVD audio and Super Audio CD (SACD), development of a speaker system capable of reproducing the original quality of the content is required.

  As a diaphragm material mounted on such a speaker system, uniform materials such as paper, plastic and metal are widely used.

  However, when a uniform material is used as the diaphragm material, the sound propagation speed is equal in all directions, so that standing waves are likely to be generated and the sound field expression may be inferior.

  For example, an obricone type diaphragm is known as a diaphragm that enriches sound field expression. The “oblicorn type diaphragm” is a diaphragm whose cross-sectional shape is asymmetric by shifting the position of the voice coil from the center of the diaphragm. By making the cross-sectional shape asymmetric, it is possible to disperse the resonance and reduce the peak appearing in the high frequency characteristics, so that a more natural reproduced sound can be obtained.

  However, the oblicorn type diaphragm is difficult to manufacture because it has a more complicated shape than a general diaphragm. In addition, since the oblicorn type diaphragm has a biased directivity, there are some cases in which it is difficult for sound to be emitted forward. Furthermore, when an obricone type diaphragm is used, the characteristics of middle and high sounds are improved, but the characteristics of low sounds may not be sufficiently improved.

  On the other hand, a wood cone type diaphragm using natural wood is also known as another diaphragm for enriching sound field expression. Wood cone type diaphragms have different propagation speeds of sound in the fiber direction and directions other than the fiber direction, so that standing waves do not occur and sound field expression and bass energy are good. A wood cone type diaphragm is described in Patent Document 1, for example.

JP 2004-254013 A

  When natural wood (wooden sheet) is used as a diaphragm, the appearance of an acoustic diaphragm that can enrich the sound field expression and has excellent reproduction characteristics of bass is desired.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a speaker that can enrich the sound field expression and has excellent reproduction characteristics of bass.

In order to achieve the above object, it comprises means described in 1) to 3) below.
That is,
1) It is arranged in a predetermined region along the direction passing through the center of the wooden diaphragm and the wooden diaphragm on the surface of the wooden diaphragm, and adjusts the propagation speed at which sound propagates in the plane of the wooden diaphragm. An acoustic diaphragm having a propagation velocity adjusting member;
A cabinet for storing the acoustic diaphragm;
With
The propagation speed adjusting member, a direction crossing the fiber direction of the wooden diaphragm as a direction passing through the center of the wooden diaphragm ,
A speaker arranged on a surface of the wooden diaphragm.
2) The speaker according to claim 1, wherein the propagation speed adjusting member is formed of an anisotropic material having a fiber direction in a direction crossing the fiber direction of the wooden diaphragm .
3) The speaker according to claim 2, wherein the propagation speed adjusting member is a wooden sheet.

  According to the present invention, it is possible to enrich the sound field expression and to obtain excellent bass reproduction characteristics.

1 is a perspective view showing a speaker according to a first embodiment of the present invention. It is sectional drawing of the speaker unit which concerns on the 1st Embodiment of this invention. It is the schematic which shows the example of a pattern of the standing wave suppression member which concerns on the 1st Embodiment of this invention. FIG. 4A to FIG. 4C are cross-sectional views showing examples of fixing the standing wave suppressing member according to the first embodiment of the present invention. It is explanatory drawing showing the measuring method of the directional sensitivity characteristic which concerns on the 1st Embodiment of this invention. It is a graph showing the measurement result of the directivity pattern which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 2nd Embodiment of this invention. It is the schematic which shows the example of a pattern of the standing wave suppression member which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 3rd Embodiment of this invention. It is the schematic which shows the example of a pattern of the standing wave suppression member which concerns on the 3rd Embodiment of this invention. It is explanatory drawing showing the measuring method of the directivity characteristic which concerns on the 3rd Embodiment of this invention. It is a graph showing the measurement result of the directivity pattern which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 4th Embodiment of this invention. It is the schematic which shows the example of a pattern of the standing wave suppression member which concerns on the 4th Embodiment of this invention. It is a graph showing the measurement result of the directivity pattern which concerns on the 4th Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 5th Embodiment of this invention. It is a perspective view which shows the speaker unit which concerns on the 5th Embodiment of this invention. It is a graph showing the measurement result of the directivity pattern which concerns on the 5th Embodiment of this invention. It is a graph showing the measurement result of the directivity pattern which concerns on the 5th Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 6th Embodiment of this invention. It is a perspective view which shows the cabinet which concerns on the 6th Embodiment of this invention. It is a perspective view which shows the speaker which concerns on the 7th Embodiment of this invention. FIG. 23A is a plan view showing a diaphragm according to a seventh embodiment of the present invention, and FIG. 23B is a cross-sectional view showing a diaphragm according to the sixth embodiment of the present invention. is there. FIG. 24A to FIG. 24G are plan views illustrating an arrangement example of the standing wave suppressing member according to the seventh embodiment of the present invention. It is a perspective view which shows the speaker which concerns on other embodiment of this invention.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is the following in terms of the structure and arrangement of components. It is not something specific.

(First embodiment)
As shown in FIG. 1, the speaker 100 a according to the first embodiment of the present invention includes a cabinet 1 having a unit mounting port 2 on the front surface and a speaker unit 3 mounted on the unit mounting port 2.

  For example, as shown in FIG. 2, the speaker unit 3 includes a magnetic circuit 34, a frame 33 disposed on the magnetic circuit 34, and a diaphragm 5 fixed to the frame 33. The magnetic circuit 34 includes a donut-shaped plate 35, a donut-shaped magnet 36 provided under the plate 35, and a pole piece 30. A voice coil 31 a is loosely inserted in the magnetic gap 37 between the plate 35 and the pole piece 30. The damper 32 is bonded to the voice coil bobbin 31 b and the frame 33.

  The diaphragm 5 is formed of a uniform material (isotropic material). “Uniform material” means a single material having substantially the same sound propagation speed in all directions in the diaphragm. Examples of the uniform material include paper such as pulp, plastic such as polypropylene, and metal such as aluminum. The wood cone type diaphragm has a complicated manufacturing method and a high manufacturing cost. However, since the diaphragm 5 is formed of a uniform material, the diaphragm 5 itself is easily and inexpensively manufactured.

  As shown in FIG. 2, the diaphragm 5 has a cone-shaped cross section, and an opening 51 is provided at the center. A dust cap 38 is attached to the opening 51 to prevent foreign matter from entering the voice coil 31a. A rubber edge or the like is attached to the outer peripheral portion (edge) 52 of the diaphragm 5 over the entire periphery, and is fixed to the frame 33 via a gasket 39.

  On the surface of the diaphragm 5, a set of standing wave suppressing members 7a and 7b for suppressing standing waves generated in the diaphragm 5 are arranged. Both the standing wave suppressing members 7a and 7b are referred to as the standing wave suppressing member 7. As shown in FIG. 1, the standing wave suppressing members 7 a and 7 b are substantially symmetrical with respect to the center of the diaphragm 5 in a direction substantially perpendicular to the bottom surface of the cabinet 1 with the dust cap 38 interposed therebetween. It is arranged so as to face each other. The thickness of the standing wave suppressing members 7a and 7b is preferably about 10 μm to 700 μm, for example, considering the relationship with the total weight of the diaphragm 5.

  The shape of the standing wave suppressing members 7a and 7b is not particularly limited. For example, plates or thin films having shapes as shown in FIGS. 3 (a) to 3 (f) can be used. For example, as shown in FIG. 3 (a), the standing wave suppressing members 7a and 7b in which the widths L1 and L2 at both ends of the standing wave suppressing members 7a and 7b are changed are attached to the diaphragm 5, so that This is preferable because the change in propagation velocity when used as a diaphragm becomes larger. Note that 0 ≦ L2 <L1. In particular, a shape (for example, FIG. 3 (a), FIG. 3 (b), FIG. 3 (c)) in which the width of the end on the opening 51 side is wider than the width of the end on the outer peripheral side is employed. Is preferred.

  As a method for fixing the standing wave suppressing members 7a and 7b, for example, as shown in the cross-sectional view of FIG. 4A, the standing wave suppressing members 7a and 7b are stuck on the entire surface of the diaphragm 5. It is preferable to attach. As an adhesion | attachment means, a double-sided adhesive tape, a commercially available adhesive agent, a thermosetting adhesive agent, a heat press etc. can be used, for example.

  However, as shown in FIG. 4B, depending on the bonding strength of the bonding means and the material of the diaphragm 5, both ends of the standing wave suppressing members 7 a and 7 b may peel off from the surface of the diaphragm 5. Although the sufficient effect can be obtained even in the example of FIG. 4B, more effectively, as shown in FIG. 4C, at least the end portion on the opening 51 side of the standing wave suppressing members 7a and 7b is provided. It is desirable to fix on the diaphragm 5 by using an adhesive means or the like so as to be in close contact with the surface of the diaphragm 5. Thereby, since the vibration transmitted from the voice coil 31a can be easily transmitted to the standing wave suppressing members 7a and 7b, the sense of sound spread in the direction in which the standing wave suppressing members 7a and 7b extend. can get.

  The material of the standing wave suppressing members 7a and 7b is preferably a material having a sound propagation speed faster than that of the material constituting the diaphragm 5. For example, when paper or polypropylene is used as the material of the diaphragm 5, carbon, aluminum, titanium, copper, or an alloy thereof can be used as the material of the standing wave suppressing members 7a and 7b, for example. In the case of using a metal such as aluminum as the material of the diaphragm 5, for example, titanium, beryllium, magnesium, or an alloy thereof can be used as the material of the standing wave suppressing members 7a and 7b.

  According to the acoustic diaphragm according to the first embodiment, as shown in FIG. 1, the standing wave suppressing member 7 a formed of a material having a sound propagation speed faster than the uniform material constituting the diaphragm 5, 7b is arranged in a direction passing through the center of the diaphragm 5, that is, in a direction substantially perpendicular to the bottom surface of the cabinet 1 (up and down direction on the paper surface). Thereby, since the speed of sound in the vertical direction becomes faster than in other directions, even when a uniform material such as paper is used as the diaphragm 5, it is possible to suppress the occurrence of standing waves and to the cabinet 1. The spread of auditory sound is born almost vertically, and the sound field can be further improved.

  In addition, according to the acoustic diaphragm according to the first embodiment, unlike the obricone diaphragm, the opening 51 is not shifted from the center of the diaphragm 5, so that the bass is not reduced. Further, standing wave suppression members 7a and 7b having the shapes shown in FIGS. 3A to 3F are cut out from a plate-like or film-like raw material, and are pasted on the surface of the diaphragm 5 with an adhesive or the like. 1, the acoustic diaphragm shown in FIG. 1 can be created, so that processing is simple and inexpensive.

  In order to investigate the characteristics of the speaker 100a shown in FIG. 1, the directional sensitivity characteristics of the speaker 100a were evaluated by the method shown in FIG. As shown in FIG. 5, in the directional sensitivity characteristic test, the speaker 100a shown in FIG. 1 was placed on a turntable (not shown) with the speaker 100a lying down sideways. Then, a microphone was placed at a radius of 1 m from the center of the turntable, and the turntable was rotated 360 degrees clockwise with the front surface of the speaker 100a being 0 degrees. A directivity pattern as shown in FIG. 6 was measured at a measurement frequency of 8 kHz. As a comparative example, the directivity pattern of a speaker not having the standing wave suppressing members 7a and 7b was measured under the same conditions as when the speaker 100a was measured.

  As can be seen from the results shown in FIG. 6, the speaker 100a (thick line: with standing wave suppression member) in which the standing wave suppression members 7a and 7b are arranged is a speaker (thin line: with the standing wave suppression members 7a and 7b). It can be seen that the level of the sound range is increased by about 3 dB in each direction as compared to the case without the standing wave suppressing member. As described above, according to the acoustic diaphragm and the speaker 100a shown in FIG. 1, even when a uniform material is used as the material of the diaphragm 5, the standing wave suppressing members 7a and 7b are arranged to be oriented. It can be seen that the characteristics can be changed and the sound spread in a specific direction.

(Second Embodiment)
In the speaker 100b according to the second embodiment of the present invention, as shown in FIG. 7, the standing wave suppressing members 7a and 7b are arranged in a substantially horizontal direction (left and right direction on the paper surface) with respect to the bottom surface of the cabinet 1. Is different from the speaker 100a shown in FIG.

  The diaphragm 5 is made of a uniform material. In FIG. 7, “uniform material” means a single material having substantially the same sound propagation speed in all directions in the diaphragm. As the uniform material, for example, paper such as pulp, plastic such as polypropylene, metal such as aluminum, and the like can be used.

  The thickness of the standing wave suppressing members 7a and 7b shown in FIG. 7 is preferably about 10 μm to 700 μm, for example, considering the relationship with the total weight of the diaphragm 5. The shape of the standing wave suppressing members 7a and 7b is not particularly limited. For example, as shown in FIGS. 8A to 8F, an elongated shape in one direction can be used. For example, as shown in FIG. 8E, the width L11 of the ends of the standing wave suppressing members 7a and 7b on the opening 51 side adjacent to the voice coil 31a (see FIG. 2) is set to the outer peripheral side of the diaphragm 5. It is preferable to use a shape that is narrower than the width L12 of the end. Thereby, the vibration generated in the voice coil 31a is easily propagated to the standing wave suppressing members 7a and 7b, and the characteristics of the propagation speed when used as a diaphragm are improved.

  The standing wave suppressing members 7a and 7b shown in FIG. 8A to FIG. 8F are, for example, using an adhesive means such as a double-sided pressure-sensitive adhesive tape, a commercially available adhesive, a thermosetting adhesive, and a heat press. You may affix on the diaphragm 5.

  As the material of the standing wave suppressing members 7 a and 7 b, it is preferable to use a material having a sound propagation speed lower than that of the uniform material constituting the diaphragm 5. Therefore, for example, when paper is used as the material of the diaphragm 5, for example, plastic such as polypropylene is used as the material of the standing wave suppressing members 7 a and 7 b. When a metal such as aluminum is used as the material of the diaphragm 5, plastics such as paper and polypropylene are used as the material of the standing wave suppressing members 7a and 7b.

  According to the acoustic diaphragm according to the second embodiment, as shown in FIG. 7, the standing wave suppressing member 7 a formed of a material whose sound propagation speed is slower than the uniform material forming the diaphragm 5, 7b is arranged in a direction passing through the center of the diaphragm 5 (almost horizontal direction with respect to the bottom surface of the cabinet 1). Thereby, since the sound speed in the substantially horizontal direction (left and right direction on the paper surface) becomes slower than that in the vertical direction, the occurrence of standing waves can be suppressed. In addition, since the sound speed in the horizontal direction is slowed down, the sound spread in the vertical direction can be obtained. Therefore, the acoustic diaphragm and the speaker 100b with a higher sound field feeling can be obtained.

  Moreover, according to the acoustic diaphragm according to the second embodiment, unlike the obricone diaphragm, the opening 51 is not shifted from the center of the diaphragm 5, so that the bass is not reduced. Further, standing wave suppression members 7a and 7b having shapes as shown in FIG. 8A to FIG. 8F are cut out from a thin film or plate-shaped raw material and attached to the surface of the diaphragm 5 with an adhesive or the like. Therefore, the acoustic diaphragm shown in FIG. 7 can be manufactured, so that the processing is simple and can be manufactured at low cost.

(Third embodiment)
As shown in FIG. 9, the speaker 100 c according to the third embodiment of the present invention includes a cabinet 1 having a unit mounting port 2 and a tweeter mounting port 6 on the front surface, and a speaker unit 3 mounted on the unit mounting port 2. And a tweeter 8 mounted on the tweeter mounting port 6. Tweeter 8 is not essential.

  The diaphragm 5 in FIG. 9 is made of wood, and is mounted in the unit mounting opening 2 so that the fiber direction is substantially perpendicular to the bottom surface of the cabinet 1 (up and down direction on the paper surface). As a tree used for the diaphragm 5, for example, in addition to conditions such as a uniform and small conduit density, a short conduit, a long wood fiber, a slow growth in summer, etc., ease of molding, acoustic characteristics, etc. Natural wood that satisfies the following conditions is preferred. For example, hippopotamus materials such as merkaba and birch, maple materials such as cypress and maple, maple materials such as hard maple, cherry and the like can be suitably used.

  A set of propagation velocities arranged on the surface of the diaphragm 5 in a direction passing through the center of the diaphragm 5, that is, in a substantially horizontal direction (left and right direction on the paper surface) with respect to the bottom surface of the cabinet 1 with the dust cap 38 interposed therebetween. Adjustment members 73a and 73b are arranged. Both of the propagation speed adjusting members 73 a and 73 b are referred to as a propagation speed adjusting member 73. When the diaphragm 5 is made of wood as described above, no standing wave is generated on the diaphragm 5. The standing wave suppressing member 7 and the propagation speed adjusting member 73 have substantially the same shape, but the propagation speed adjusting member 73 acts as a member for adjusting the propagation speed for propagating sound in the plane of the diaphragm 5. It will be referred to as a propagation speed adjusting member. The thickness of the propagation speed adjusting members 73a and 73b is preferably about 10 μm to 700 μm, for example, considering the relationship with the total weight of the diaphragm 5.

  As the material of the propagation speed adjusting members 73a and 73b, it is preferable to use a material having a sound propagation speed faster than that of the diaphragm 5. For example, when natural wood is used as the propagation speed adjusting members 73a and 73b, for example, as shown in FIG. 9, a wooden sheet having a fiber direction (for example, the left-right direction on the paper) different from the fiber direction of the diaphragm 5 is vibrated. It can be attached to the surface of the plate 5.

  The wooden sheet used as a material for the diaphragm 5 and the propagation speed adjusting members 73a and 73b generally has a certain fiber direction. The propagation speed in the fiber direction of the wooden sheet shows a high value, but the propagation speed is significantly reduced in the direction perpendicular to the fiber direction. For this reason, when a large-diameter wood cone speaker is manufactured using a wooden sheet, the slow propagation speed of the sound in the horizontal direction affects the reproduced sound, making it difficult for the sound to come forward and lack of sound field expression. Can occur.

  On the other hand, as shown in FIG. 9, by arranging the propagation speed adjusting members 73a and 73b in the substantially horizontal direction with respect to the bottom surface of the cabinet 1, the horizontal sound velocity can be increased, so that the large diameter Even when a wood cone speaker is manufactured, it is possible to provide a sound diaphragm and speaker 100c that can suppress degradation of reproduced sound due to a delay in propagation speed in the non-fiber direction, has a rich sound field expression, and good directivity. .

  In the third embodiment, uniform materials such as paper and aluminum may be substituted for the propagation speed adjusting members 73a and 73b. In addition to natural wood, other anisotropic materials having a fiber direction, for example, fibrous materials such as carbon and aramid may be used.

  Moreover, although the shape of the propagation velocity adjusting members 73a and 73b is not particularly limited, for example, as shown in FIGS. 10 (a) to 10 (f), a plate or thin film that is elongated in one direction can be employed. For example, as shown in FIG. 10 (a), the widths L1 and L2 at both ends of the propagation velocity adjusting members 73a and 73b are changed, or FIG. 10 (b), FIG. 10 (c), FIG. 10 (e), FIG. 10 (f), when the width of the propagation speed adjusting members 73a and 73b is changed in the longitudinal direction of the propagation speed adjusting members 73a and 73b, when the adhesive is attached to the diaphragm 5, The speed of sound can be changed. Note that 0 ≦ L2 <L1. Further, in order to make it easier to transmit the vibration generated in the voice coil 31a, the width of the end on the opening 51 side adjacent to the voice coil 31a is made wider than the width l2 of the other end. 10 (b) and a shape as shown in FIG. 10 (c) may be employed.

  According to the acoustic diaphragm according to the third embodiment, as shown in FIG. 9, the propagation speed adjusting members 73a and 73b formed of a material having a faster propagation speed than the material constituting the diaphragm 5, It arrange | positions in the substantially horizontal direction (paper surface left-right direction) with respect to the facing of the cabinet 1. FIG. As a result, the sound speed in the horizontal direction of the diaphragm 5 is increased. Therefore, even when a natural wood (wooden sheet) that is an anisotropic material is used as the diaphragm 5, the delay in the sound speed in the horizontal direction can be alleviated. The field expression can be further improved.

  Further, when natural wood is used as the diaphragm 5, the larger the outer diameter of the diaphragm, the more easily defects such as cracks occur along the fiber direction. According to the acoustic diaphragm and the speaker 100c shown in FIG. 9, since the propagation speed adjusting members 73a and 73b are formed in the direction where the mechanical strength is weak, it also serves as a reinforcing material. In particular, the manufacturing yield in the case of manufacturing a large-diameter diaphragm can be improved.

  In addition, according to the acoustic diaphragm according to the third embodiment, unlike the obricone diaphragm, the opening 51 is not shifted from the center of the diaphragm 5, so the bass is not reduced. Further, the propagation speed adjusting members 73a and 73b having the shapes shown in FIGS. 10A to 10F are cut out from a plate-like or film-like material, and are pasted on the surface of the diaphragm 5 with an adhesive or the like. Only the acoustic diaphragm shown in FIG. 9 can be produced, so that the processing is simple and can be manufactured at low cost.

  Here, in order to investigate the characteristics of the speaker 100c shown in FIG. 9, the directional sensitivity characteristics of the speaker 100c were evaluated as shown in FIG. In FIG. 11, the speaker 100c shown in FIG. 9 is placed on a turntable (not shown) as it is, a microphone is placed at a radius of 1 m from the center of the turntable, the front surface of the speaker 100c is set to 0 degrees, and clockwise. The directivity pattern was measured by rotating the turntable 360 degrees. The measurement frequency was 8 kHz. The obtained directivity pattern is shown in FIG.

  As can be seen from the results shown in FIG. 12, by arranging the propagation velocity adjusting members 73a and 73b (thick line: with standing wave suppressing member), compared with the case without arranging (thin line: without standing wave suppressing member), In particular, it can be seen that the sound level in the direction of 30 degrees to 120 degrees is improved by about 5 dB. As described above, according to the acoustic diaphragm and the speaker 100a shown in FIG. 9, even when natural wood is used as the material of the diaphragm 5, sound can be output to the front, and sound field expression can be further improved. Can do.

(Fourth embodiment)
As shown in FIG. 13, the speaker 100 d according to the fourth embodiment of the present invention includes a cabinet 1 having a unit mounting port 2 and a tweeter mounting port 6 on the front surface, and a speaker unit 3 mounted on the unit mounting port 2. And a tweeter 8 mounted on the tweeter mounting port 6. Tweeter 8 is not essential.

  The diaphragm 5 is made of a uniform material. In FIG. 13, “uniform material” means a single material having substantially the same sound propagation speed in all directions in the diaphragm. As the uniform material, for example, paper such as pulp, plastic such as polypropylene, metal such as aluminum, and the like are used.

  As the material of the standing wave suppressing members 7 a and 7 b in FIG. 13, a material having anisotropy and having a sound propagation speed faster than that of the diaphragm 5 is used. For example, the standing wave suppressing members 7a and 7b in FIG. 13 are wooden sheets, and vibrate with the dust cap 38 interposed therebetween so that the fiber direction is substantially perpendicular to the bottom surface of the cabinet 1 (up and down direction on the paper surface). Affixed to the top and bottom of the plate 5. As the material used for the standing wave suppressing members 7a and 7b, for example, in addition to conditions such as a uniform and small conduit density, a short conduit, a long wood fiber, and a slow growth of Natsume, a molding process is performed. A material that satisfies each condition such as ease and acoustic characteristics is preferable. For example, hippopotamus materials such as merkaba and birch, maple materials such as cypress and itayaka maple, maple materials such as hard maple, cherry and the like can be suitably used. In addition to natural wood, other anisotropic materials having different propagation velocities in the horizontal direction and the vertical direction may be used as the material of the standing wave suppressing members 7a and 7b.

  The thickness of the standing wave suppressing members 7a and 7b is preferably about 10 μm to 700 μm in consideration of the relationship with the total weight of the diaphragm 5. The shape of the standing wave suppressing members 7a and 7b is not particularly limited. For example, plates or thin films having shapes as shown in FIGS. 14 (a) to 14 (f) can be used. For example, as shown in FIGS. 14 (a), 14 (b), 14 (c), 14 (e), and 14 (f), the standing wave suppressing member 7a with the widths at both ends changed, By attaching 7b to the diaphragm 5, vibration generated in the voice coil 31a is easily propagated to the standing wave suppressing members 7a and 7b. In particular, in order to make it easier to transmit the vibration generated in the voice coil 31a, the width of the end on the opening 51 side adjacent to the voice coil 31a is wider than the width of the other end. b) A shape as shown in FIG. 14C is particularly preferable.

  According to the acoustic diaphragm according to the fourth embodiment, as shown in FIG. 13, the standing wave suppressing member 7 a formed of an anisotropic material having a faster propagation speed than the material constituting the diaphragm 5, 7b is arranged in a direction substantially perpendicular to the bottom surface of the cabinet 1 (up and down direction on the paper surface). As a result, the sound speed in the vertical direction becomes faster than the other directions, so that the directivity characteristics in the vertical direction are widened, and a feeling of sound spread in the vertical direction is obtained.

  Further, according to the acoustic diaphragm according to the fourth embodiment, unlike the obricone diaphragm, the opening 51 is not shifted from the center of the diaphragm 5, so that the bass is not reduced. Further, the standing wave suppressing members 7a and 7b having the shapes shown in FIGS. 14A to 14F are cut out from a plate-like or film-like material and attached to the surface of the diaphragm 5 with an adhesive or the like. Since the acoustic diaphragm shown in FIG. 13 can be created simply by attaching, processing is simple and can be manufactured at low cost.

  Here, in order to investigate the characteristics of the speaker 100d shown in FIG. 13, the directional sensitivity characteristics of the speaker 100d were evaluated in the same manner as in the example shown in FIG. As a comparative example, the directional sensitivity characteristics of a speaker not including any standing wave suppressing members 7a and 7b were evaluated.

  As can be seen from the results shown in FIG. 15, the standing wave suppressing members 7a and 7b are arranged (thick line: with standing wave suppressing member), compared with a speaker not arranged at all (thin line: without standing wave suppressing member). In particular, it can be seen that the sound range level in the direction of 0 degrees to 120 degrees is greatly improved.

(Fifth embodiment)
As shown in FIG. 16, the speaker 100 e according to the fifth embodiment of the present invention includes the cabinet 1, the speaker unit 3 and the tweeter 8 mounted on the front surface of the cabinet 1, and the surface of the diaphragm 5. The surface standing wave suppressing members 7a and 7b disposed on the back surface and the back surface standing wave suppressing members 17a and 17b disposed on the back surface of the diaphragm 5 as shown in FIG. To the acoustic diaphragm and the speakers 100a to 100d according to the fourth embodiment. Tweeter 8 is not essential.

  The back surface standing wave suppressing member 17 a is disposed at a position facing the surface standing wave suppressing member 7 a through the diaphragm 5. The back surface standing wave suppressing member 17 b that is not visible in FIG. 17 is disposed at a position facing the surface standing wave suppressing member 7 a through the diaphragm 5.

  As materials for the front surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b, those having a propagation velocity higher than that of the diaphragm 5 are used. For example, when paper or polypropylene is used as the material of the diaphragm 5, the materials of the front surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b are, for example, carbon, aluminum, titanium, copper, Those alloys can be used. When a metal such as aluminum is used as the material of the diaphragm 5, examples of the material of the surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b include titanium, beryllium, magnesium, or these Alloys can be used.

  When natural wood (wood sheet) is used as the material of the diaphragm 5, the surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b are as described in the third embodiment. It becomes a propagation speed adjusting member. As the propagation speed adjusting member, carbon, aluminum, titanium, copper, or an alloy thereof, or other natural wood or anisotropic material having a propagation speed higher than that of the diaphragm 5 can be used. Others are substantially the same as the acoustic diaphragms and speakers 100a to 100d according to the first to fourth embodiments.

  According to the acoustic diaphragm and speaker 100e shown in FIGS. 16 and 17, the surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b are disposed on the front and back surfaces of the diaphragm 5. As a result, the speed of sound in a direction substantially perpendicular to the bottom surface of the cabinet 1 becomes faster than in other directions, so that even when a uniform material such as paper is used as the diaphragm 5, the occurrence of standing waves can be suppressed. , The sound will come out more in front.

  Further, when natural wood is used as the diaphragm 5, by forming the front surface propagation speed adjusting member and the back surface propagation speed adjusting member, the acoustic diaphragm and speaker 100e with rich sound field expression and good directivity characteristics can be obtained. Can be provided. Since the mechanical strength of the diaphragm 5 is increased, it is possible to improve the manufacturing yield particularly when manufacturing a diaphragm having a large diameter.

  Furthermore, according to the acoustic diaphragm according to the fifth embodiment, unlike the obricone diaphragm, the opening 51 is not shifted from the center of the diaphragm 5, so the bass is not reduced. Further, the surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b having a desired shape are cut out from the plate-like or film-like raw material, and adhesive or the like is applied to the front and back surfaces of the diaphragm 5. Since the acoustic diaphragm shown in FIGS. 16 and 17 can be created simply by pasting, processing is simple and can be manufactured at low cost.

  Here, in order to investigate the characteristics of the speaker 100e shown in FIG. 16, the directional sensitivity characteristics of the speaker 100e were evaluated in the same manner as in the example shown in FIG. As a first comparative example, the directional sensitivity characteristics of a speaker that does not include the front surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b were evaluated (see FIG. 18). As a second comparative example, directional sensitivity characteristics of a speaker provided with only surface standing wave suppressing members 7a and 7b were also evaluated (see FIG. 19).

  As can be seen from the results shown in FIG. 18, by arranging the surface standing wave suppressing members 7a and 7b and the back surface standing wave suppressing members 17a and 17b (thick line: standing wave suppressing member), a speaker that is not arranged at all ( In particular, it can be seen that the sound range level in the direction of 60 degrees to 120 degrees and the direction of 240 degrees to 360 degrees is greatly improved compared to the thin line: no standing wave suppressing member.

  Further, as can be seen from the results shown in FIG. 19, when the surface standing wave suppressing members 7 a and 7 b and the back surface standing wave suppressing members 17 a and 17 b are arranged on both surfaces of the diaphragm 5 (thick line: back surface standing wave suppressing member). It can be seen that the sound range level in the direction of 90 to 150 degrees and in the direction of 240 to 360 degrees is improved as compared with the case where it is disposed only on the front surface (thin line: no back surface standing wave suppressing member).

(Sixth embodiment)
As shown in FIG. 20, the speaker 100 f according to the sixth embodiment of the present invention includes an amplifier housing 4 that houses the amplifier 40 provided in the center, and a unit mounting port 2 a that is provided around the amplifier 40. 2b, and speaker units 3a and 3b mounted in the unit mounting ports 2a and 2b, respectively.

  The cabinet 1 is made of wood, and as shown in FIG. 21, it is an integral type that can simultaneously store the speaker units 3a and 3b and the amplifier 40. The distance between the speaker units 3a and 3b is, for example, about 15 to 60 cm.

  The speaker unit 3a includes a diaphragm 5a and a pair of first standing wave suppressing members 70a and 70b disposed substantially horizontally with respect to the bottom surface of the cabinet 1 with the dust cap 38a interposed therebetween. And a pair of second standing wave suppressing members 70c and 70d disposed in the upper left direction and the lower right direction on the paper with the dust cap 38a interposed therebetween.

  The speaker unit 3b includes a diaphragm 5b and a pair of first standing wave suppressing members 72a and 72b disposed in a substantially horizontal direction (left and right direction in the drawing) with respect to the bottom surface of the cabinet 1 with the dust cap 38b interposed therebetween. And a pair of second standing wave suppressing members 72c and 72d disposed in the upper right direction and the lower left direction of the paper with the dust cap 38b interposed therebetween.

  In FIG. 20, the second standing wave suppressing members 70c and 70d and the second standing wave suppressing members 72c and 72d pass through the center of the cabinet and are based on a plane perpendicular to the bottom surface of the cabinet. The positions are adjusted so that they are inclined in opposite directions. As a result, the speed of sound reproduced from the speaker unit 3a on the left side of the paper increases in the diagonally left direction. On the other hand, the sound reproduced from the speaker unit 3b on the right side of the paper has a higher sound speed in the diagonally right direction.

  The diaphragms 5a and 5b are formed of a uniform material or natural wood similar to that described in the first to fourth embodiments. When the diaphragms 5a and 5b are made of natural wood, the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c, and 72d are as described in the third embodiment. It becomes a propagation speed adjusting member. As the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c, 72d, a material having a faster propagation speed than the diaphragms 5a, 5b is used. For example, when paper or polypropylene is used as the diaphragms 5a and 5b, the material of the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c, 72d is, for example, carbon, aluminum, titanium, copper Or those alloys etc. can be used. When a metal such as aluminum is used as the material of the diaphragms 5a and 5b, the material of the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c and 72d is, for example, titanium, beryllium, magnesium, Alternatively, these alloys can be used. When the fiber direction of the natural wood used for the diaphragms 5a and 5b is the vertical direction of the paper, natural wood or anisotropic material having a fiber direction in the horizontal direction of the paper can be used.

  The thickness of the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c, 72d is preferably about 10 μm to 700 μm in consideration of the relationship with the total weight of the diaphragms 5a, 5b. Others are substantially the same as the acoustic diaphragm and the speakers 100a to 100e described in the first to fourth embodiments.

  According to the acoustic diaphragm and the speaker 100f according to the sixth embodiment, by including the standing wave suppressing members 70a, 70b, 70c, 70d, 72a, 72b, 72c, 72d (or a propagation speed adjusting member), The sound propagation speed changes in the planes of the diaphragms 5a and 5b. As a result, even when a uniform material such as paper is used, the generation of standing waves can be suppressed, the sound field expression can be improved, and the sound can come out to the foreground. Sound can be played.

  In particular, the speaker 100f as shown in FIG. 20 is configured as an integrated type in which the speaker unit 3a and the speaker unit 3b are relatively close to each other. The sound field was lacking. However, the standing wave suppressing members 70a, 70b, 70c, and 70d (or propagation speed adjusting members) are arranged on the left diaphragm 5a so that the sound velocity in the left-right direction and the left oblique direction is increased. Standing wave suppressing members 72a, 72b, 72c, 72d (or propagation speed adjusting members) are arranged on the right diaphragm 5b so that the sound speeds in the left-right direction and the right diagonal direction are increased. As a result, even with the integrated speaker 100f having a short distance between the speaker units 3a and 3b, it is possible to reproduce a sound with a more three-dimensional effect than the conventional apparatus.

(Seventh embodiment)
As shown in FIG. 22, the speaker unit 9 according to the seventh embodiment of the present invention has a magnetic circuit 91, a storage portion 92 that stores the magnetic circuit 91, and a dome shape disposed on the magnetic circuit 91. The diaphragm 50 has a belt-like standing wave suppressing member 27 disposed on the surface of the diaphragm 50, and a frame 93 that fixes the diaphragm 50.

  As the diaphragm 50, silk, cotton, hemp, chemical fiber, film, or the like can be used in addition to the uniform material and the wooden sheet shown in the first to sixth embodiments. A cloth edge having a predetermined shape is formed on the outer circumferential portion 54 of the diaphragm 50 over the entire circumference. As shown in FIGS. 23A and 23B, the standing wave suppressing member 27 is adhered in a straight line to the dome portion of the diaphragm 50 by an adhesive means. The thickness of the standing wave suppressing member 27 is preferably about 10 μm to 700 μm in consideration of the total weight of the diaphragm 50. Since the curvature of the dome portion of the diaphragm 50 is relatively large, peeling may occur depending on the material of the standing wave suppressing member 27 and the bonding strength of the bonding means. Therefore, the width of the band of the standing wave suppressing member 27 is preferably about 1 mm.

  The material of the standing wave suppressing member 27 can be selected according to the application. For example, by using a material having a higher propagation speed than the diaphragm 50 as the standing wave suppressing member 27, the sound speed in the vertical direction of the paper in FIG. A range of auditory sounds in the direction can be obtained. Conversely, by using a material having a slower propagation speed than the diaphragm 50 as the standing wave suppressing member 27, the sound speed in the vertical direction on the paper surface of FIG. The left and right auditory sound spread is obtained. Further, when an anisotropic material such as natural wood is used as the standing wave suppressing member 27, a sound spread different from that shown in FIG. The arrangement pattern of the standing wave suppressing member 27 is not limited to the example shown in FIGS. 24A and 24B, and for example, as shown in FIG. 24C, a cross shape may be used. As shown in FIG. 24D to FIG. 24G, a V shape may be used.

(Other embodiments)
Although the present invention has been described according to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  As shown in FIG. 25, in the first to sixth embodiments, even if the auxiliary member 77 attached in the same direction as the standing wave suppressing members 7a and 7b is disposed on the dust cap 38. Good. By arranging the auxiliary member 77, if the material has a propagation speed higher than that of the dust cap, the directivity characteristic in the vertical direction of the paper surface is widened, so that the auditory sound spread in the vertical direction of the paper surface can be obtained.

  In the first to sixth embodiments, an example in which two standing wave suppressing members 7a and 7b (or propagation speed adjusting members 73a and 73b) facing each other with the dust cap 38 interposed therebetween is shown. A single standing wave suppressing member (or propagation speed adjusting member) extending from the opening 51 to the outer peripheral portion may be disposed. However, since the weight balance as the diaphragm 5 is impaired, the pair of standing wave suppressing members 7a and 7b (propagation speed adjusting members 73a and 73b) is set to 1 so as to be symmetrical with the dust cap 38 in the cross section. It is desirable to arrange in the direction.

  In the first to sixth embodiments, a full-band type speaker and a speaker equipped with a tweeter are exemplified, but in addition to a tweeter, a mid-range, woofer, etc. are mounted and a speaker having a 2-5 way structure. May be constructed.

  As described above, the present invention includes various embodiments and the like not described herein, and various modifications can be made without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 ... Cabinet 2, 2a ... Unit installation port 3, 3a, 3b ... Speaker unit 4 ... Amplifier storage part 5, 5a, 5b ... Diaphragm 6 ... Tweeter installation port 7a, 7b, 17a ... Standing wave suppression member 8 ... Tweeter DESCRIPTION OF SYMBOLS 9 ... Speaker unit 30 ... Pole piece 31a ... Voice coil 31b ... Voice coil bobbin 32 ... Damper 33 ... Frame 34 ... Magnetic circuit 35 ... Plate 36 ... Magnet 37 ... Magnetic gap 38 ... Dust cap 39 ... Gasket 40 ... Amplifier 50 ... Diaphragm DESCRIPTION OF SYMBOLS 51 ... Opening part 52 ... Outer peripheral part 54 ... Outer peripheral part 73a, 73b ... Propagation speed adjustment member 77 ... Auxiliary member 91 ... Magnetic circuit 92 ... Storage part 93 ... Frame 100a-100f ... Speaker

Claims (3)

Propagation speed for adjusting the propagation speed of sound transmitted in the plane of the wooden diaphragm and the wooden diaphragm and a predetermined region along the direction passing through the center of the wooden diaphragm on the surface of the wooden diaphragm An acoustic diaphragm having an adjustment member;
A cabinet for storing the acoustic diaphragm;
With
The propagation speed adjusting member, a direction crossing the fiber direction of the wooden diaphragm as a direction passing through the center of the wooden diaphragm ,
A speaker arranged on a surface of the wooden diaphragm. The speaker according to claim 1, wherein the propagation speed adjusting member is formed of an anisotropic material having a fiber direction in a direction crossing the fiber direction of the wooden diaphragm .   The speaker according to claim 2, wherein the propagation speed adjusting member is a wooden sheet.

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