JP2005102166A - Loudspeaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a loudspeaker in an elongated structure capable of improving bonding strength between a diaphragm and a coil. <P>SOLUTION: The loudspeaker includes a diaphragm, an edge, and a voice coil. The diaphragm includes a groove having a concave cross section. Also, the diaphragm is in a horizontally or vertically elongated shape. The edge is coupled to the outer circumference of the diaphragm, and has a roughly half-round shaped cross section. The voice coil is bonded to the groove. The voice coil is thicker than the depth of the groove. Also, the voice coil has a cross section in which a dimension in a direction along a plane of the diaphragm is longer than a dimension in a direction perpendicular to the plane of the diaphragm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a speaker, and more particularly to a speaker used in various audio equipment such as video and audio equipment.

  Conventionally, in audiovisual equipment such as a television, the speaker is attached to both sides of the cathode ray tube. Therefore, a rectangular or elliptical speaker has been used as the audiovisual equipment speaker. Further, in recent years, speakers for audiovisual equipment have been required to have a narrower width as the display screen becomes wider, and are thinner to accommodate devices with a small depth such as liquid crystal displays and plasma displays. There is a need to make it easier.

  Here, a conventional slender speaker will be described with reference to FIGS. FIG. 17 is a plan view of a conventional elongated speaker, FIG. 18 is a side sectional view in the major axis direction of the speaker, and FIG. 19 is a side sectional view in the minor axis direction of the speaker. 17 to 19, the diaphragm 1 that generates air vibration has an elongated shape, and the outer peripheral portion of the diaphragm 1 is held by the frame 3 via the edge 2. A voice coil 4 is fixed to the planar portion of the diaphragm 1.

  On the other hand, a magnetic circuit 8 including a yoke 5, a magnet 6, and a top plate 7 is provided at the center of the frame 3. In FIG. 19, the magnet 6 is magnetized in a direction perpendicular to the diaphragm 1 (the direction of the arrow Z shown in FIG. 19). Therefore, a magnetic gap 9 is generated between the opening of the yoke 5 (in the vicinity of the edge 2) and the top plate 7 in which a magnetic flux directed in a direction perpendicular to the diaphragm 1 is generated. The voice coil 4 is disposed in the magnetic gap 9 in a direction perpendicular to the magnetic flux (in FIG. 19, a direction perpendicular to the paper surface). Therefore, when an alternating current is passed through the voice coil 4, the diaphragm 1 vibrates in the direction of the arrow Z shown in FIG. 19, and a sound wave is radiated into the space.

For example, Patent Document 1 and Patent Document 2 are prior art documents relating to the above-described elongated speaker.
JP-A-10-191494 JP 57-39697 A

  In the conventional speaker, the voice coil is bonded to the flat plate portion of the diaphragm with an adhesive. Here, since the cross section of each wire of the voice coil is circular, the contact area between the voice coil and the diaphragm is small. In addition, since the adhesive easily spreads thinly on the diaphragm, the adhesive layer made of the adhesive becomes thin. Due to the small contact area and the thin adhesive layer, the adhesive strength between the voice coil and the diaphragm was low. For this reason, the diaphragm and the voice coil are isolated from each other, resulting in problems that the distortion of the diaphragm during vibration increases and vibration failure occurs.

  In particular, in the case of a speaker having an elongated structure, it is necessary to improve the adhesive strength between the diaphragm and the coil because the diaphragm is easily distorted during vibration. In addition, in a coil whose cross section is horizontally long (when the vibration direction of the diaphragm is a vertical direction, a coil whose cross section is vertically short and long horizontally), when the adhesive strength between the voice coil and the diaphragm is small, There is a possibility that the coil wires are separated from each other by vibration of the diaphragm. If the coil wires are separated from each other, the quality of the reproduced sound is degraded.

  Therefore, an object of the present invention is to provide a speaker having an elongated structure capable of improving the adhesive strength between a diaphragm and a coil.

  In order to achieve the above object, the present invention has the following features. In other words, the first invention is a speaker including a diaphragm, an edge, and a voice coil. The diaphragm has a groove having a concave cross section. The diaphragm has a horizontally long or vertically long shape. The edge is connected to the outer periphery of the diaphragm and has a substantially semicircular cross section. The voice coil is bonded to the groove. Here, the voice coil is thicker than the depth of the groove. Further, the voice coil has a longer cross section in the direction along the surface of the diaphragm than in the direction perpendicular to the diaphragm.

  In addition, the adhesive agent which adhere | attaches a voice coil and a diaphragm may be formed in a fillet shape in the side surface of a voice coil.

  A plurality of protrusions smaller than the diameter of the voice coil may be provided on the bonding surface between the groove and the voice coil.

  Moreover, 2nd invention is a speaker provided with a diaphragm, an edge, a voice coil, and a film. The diaphragm has a groove having a concave cross section. The diaphragm has a horizontally long or vertically long shape. The edge is connected to the outer periphery of the diaphragm and has a substantially semicircular cross section. The voice coil is bonded to the groove. The film is fixed to the diaphragm and the voice coil so as to cover the voice coil on the opposite side of the bonding surface between the voice coil and the diaphragm.

  In addition, a film is comprised by either the polymer film, the polymer film by which metal foil was vapor-deposited, and metal foil, for example.

  The film may be a material having viscoelasticity.

  Moreover, 3rd invention is a speaker provided with a diaphragm, an edge, a shock absorbing material, and a voice coil. The diaphragm has a groove having a concave cross section. The diaphragm has a horizontally long or vertically long shape. The edge is connected to the outer periphery of the diaphragm and has a substantially semicircular cross section. The cushioning material is bonded to the groove and has a planar shape. The voice coil is bonded to the groove via a cushioning material.

  The cross section along the longitudinal direction of the diaphragm may have an arch shape that is lower than the edge.

  According to the first invention, the adhesive for bonding the voice coil and the diaphragm accumulates in the groove, and the voice coil and the diaphragm can be bonded with an adhesive having a sufficient thickness. Therefore, the adhesive strength between the voice coil and the diaphragm can be increased as compared with the conventional case. Thereby, the reproduction sound quality of the speaker can be improved. According to the first invention, since the voice coil is bonded to the diaphragm so as to have a horizontally long shape, the thickness of the speaker can be reduced and the sound quality of the reproduced sound can be improved. Furthermore, according to the first aspect of the present invention, the diaphragm and the voice coil can be sufficiently pressurized when the diaphragm and the voice coil are bonded, so that both can be bonded more firmly. Furthermore, according to the first invention, the rigidity of the diaphragm is increased by the groove, so that the high-band resonance frequency of the diaphragm can be increased, and a speaker having excellent reproduction characteristics can be provided.

  Further, when the adhesive for bonding the voice coil and the diaphragm is formed in a fillet shape on the side surface of the voice coil, the bonding strength between the voice coil and the diaphragm can be further increased.

  Further, when the protrusion is provided in the groove, the contact area between the adhesive and the diaphragm increases, so that the adhesive strength between the diaphragm and the voice coil can be further increased.

  Further, according to the second invention, similarly to the first invention, the adhesive strength between the voice coil and the diaphragm can be increased by the structure having the groove, and the reproduction sound quality of the speaker can be improved. Furthermore, the adhesive strength between the voice coil and the diaphragm can also be increased by adopting a configuration in which the voice coil is sandwiched between the diaphragm and the film.

  Moreover, when making the polymer film which vapor-deposited metal foil or metal foil into the said film, the temperature rise of a voice coil can be reduced with the heat conductive effect of a film. Therefore, it is possible to realize a speaker that can operate even with a larger input.

  When the film is made of a material having viscoelasticity, unnecessary resonance of the voice coil can be prevented by the internal loss of the film. Therefore, the distortion at the time of vibration of the diaphragm can be further reduced.

  Further, according to the third invention, similar to the first invention, the adhesive strength between the voice coil and the diaphragm can be increased by the structure having the groove, so that the reproduction sound quality of the speaker can be improved. Furthermore, by providing a buffer material between the diaphragm and the voice coil, unnecessary resonance of the voice coil can be suppressed by the internal loss of the buffer material, and the sound quality of the speaker can be improved.

  Further, when the cross section of the diaphragm is formed in an arch shape, the rigidity of the diaphragm can be increased as compared with the case where the cross section of the diaphragm is a straight line. As a result, the high-frequency resonance frequency of the diaphragm can be increased, so that a speaker having excellent reproduction characteristics can be provided.

(Embodiment 1)
First, the speaker according to Embodiment 1 of the present invention will be described. FIG. 1 is a plan view of the speaker, FIG. 2 is a cross-sectional view (AB cross-sectional view) in the major axis direction of the speaker, and FIG. ). 1 to 3, the speaker includes a diaphragm 101, an edge 102, a frame 104, a voice coil 105, a yoke 107, a magnet 108, and a top plate 109. As shown in FIG. 1, the speaker has a vertically long shape (also referred to as a horizontally long shape). In the following, the side (left side in FIG. 2) where the diaphragm 101 is provided in the speaker is referred to as the upper surface side, and the side where the yoke 107 is provided (right side in FIG. 2) is referred to as the lower surface side. Further, the longitudinal direction of the diaphragm 101 on a substantially flat surface is referred to as a major axis direction, and a direction perpendicular to the major axis direction is referred to as a minor axis direction.

  As shown in FIGS. 1 to 3, the diaphragm 101 has a planar shape except that a groove 103 described later is provided. The diaphragm 101 has a vertically long shape (also referred to as a horizontally long shape). Specifically, the diaphragm 101 has a shape in which two parallel sides facing each other are connected by an arc. The diaphragm 101 is, for example, a thin and strong film such as a polyimide material, or a lightweight and highly rigid paper material. An edge 102 is annularly provided on the outer periphery of the diaphragm 101. The edge 102 has a substantially semicircular cross section. The outer periphery of the edge 102 is connected to the frame 104 and the yoke 107. In the first embodiment, both ends of the edge 102 in the major axis direction (vertical direction in FIG. 1) are connected to the frame 104, and the center part of the edge 102 in the major axis direction is connected to the yoke 107. As described above, the diaphragm 101 is held by the frame 104 and the yoke 107 via the edge 102.

  As shown in FIGS. 2 and 3, a yoke 107 is connected to the center of the frame 104 in the major axis direction. A magnet 108 is connected to the upper surface side of the yoke 107. Further, a top plate 109 is connected to the upper surface side of the magnet 108. The yoke 107, the magnet 108, and the top plate 109 constitute a magnetic circuit 110. The voice coil 105 is bonded to the diaphragm 101 so as to be disposed in the magnetic gap of the magnetic circuit 110. The voice coil 105 has a configuration in which an electric wire made of copper, aluminum silver, or the like covered with an insulating film is wound a plurality of times. 1 to 3, the driving force is generated in the voice coil 105 by passing an alternating current through the voice coil 105, and the diaphragm 101 bonded to the voice coil 105 vibrates to emit sound. Is done.

  Here, in Embodiment 1, a groove 103 having a concave cross section is formed in diaphragm 101 (see FIGS. 2 and 3). The voice coil 105 is bonded to the bottom of the concave portion of the groove 103 with an adhesive 106. The groove 103 is formed in an annular shape in accordance with the shape of the voice coil 105. That is, in Embodiment 1, since the shape of the voice coil 105 viewed from the upper surface side is a rectangle that is long in the major axis direction, the groove 103 is formed in a rectangle (see FIG. 1). In the first embodiment, the groove 103 is formed in a convex shape on the upper surface side, and the voice coil 105 is bonded to the lower surface side of the diaphragm 101, but the groove 103 is formed in a convex shape on the lower surface side, and the voice The coil 105 may be bonded to the upper surface side of the vibration plate 101.

  As described above, the voice coil 105 is bonded to the position of the groove 103 provided in the diaphragm 101 with the adhesive 106. Since the groove 103 has a concave cross section, the adhesive 106 does not expand along the plane of the vibration plate 101 but is stored at the bottom of the groove 103. Therefore, since the voice coil 105 and the diaphragm 101 can be bonded with the adhesive 106 having a sufficient thickness, the bonding strength between the voice coil 105 and the diaphragm 101 can be increased. That is, according to the first embodiment, it is possible to prevent the voice coil 105 from being peeled off from the diaphragm 101 due to the vibration of the diaphragm 101, so that chatter noise is generated and the distortion of the diaphragm during the vibration is increased. Can be prevented. As a result, the sound quality of the reproduced sound can be improved.

  In the first embodiment, the voice coil 105 is bonded to the diaphragm 101 so as to have a horizontally long shape. Specifically, the cross-sectional shape of the voice coil 105 is bonded so that the length in the direction along the plane portion of the diaphragm 101 is longer than the length in the direction perpendicular to the diaphragm 101 ( 2 and 3). This is for the purpose of thinning the speaker and the purpose of making the vibration of the diaphragm 101 an ideal piston motion by increasing the contact portion between the voice coil 105 and the diaphragm 101. Here, when the voice coil 105 has a horizontally long shape, each electric wire of the voice coil 105 is likely to be separated due to the vibration of the diaphragm 101, and the sound quality of the reproduced sound may be deteriorated if the electric wires are separated. is there. However, in Embodiment 1, since the adhesive strength between diaphragm 101 and voice coil 105 can be increased, there is no possibility that the wires of voice coil 105 are separated from each other. Therefore, according to the speaker according to Embodiment 1, it is possible to prevent the sound quality of the reproduced sound from being deteriorated.

  In the first embodiment, the voice coil 105 is configured to be thicker than the depth of the groove 103 (see FIGS. 2 and 3). In other words, the depth of the groove 103 is formed lower than the thickness of the voice coil 105. Thus, when the diaphragm 101 and the voice coil 105 are bonded, the diaphragm 101 and the voice coil 105 can be pressurized. That is, since both are brought into close contact with each other without generating a gap between the diaphragm 101 and the voice coil 105, both can be bonded more firmly.

  As described above, according to the first embodiment, the groove 103 is provided in the diaphragm 101, and the voice coil 105 is bonded to the position of the groove 103, thereby improving the bonding strength between the diaphragm 101 and the voice coil 105. be able to. Thereby, the reproduction sound quality can be improved.

  Furthermore, according to the first embodiment, by providing the diaphragm 103 with the groove 103, the bending rigidity of the diaphragm 101 can be increased. By increasing the bending rigidity of the vibration plate 101, the resonance frequency (high frequency resonance frequency) inherent to the vibration plate generated in a high frequency region can be increased. For this reason, it is possible to cause the diaphragm 101 to perform a piston motion up to a higher frequency.

  4A and 4B are diagrams showing sound pressure frequency characteristics of the speaker according to Embodiment 1 and the conventional speaker. That is, FIG. 4A is a diagram showing a result of analyzing and calculating sound pressure frequency characteristics of a speaker using the conventional planar diaphragm shown in FIG. 17 by FEM (finite element method). In FIGS. 4A and 4B, the horizontal axis indicates the frequency, and the vertical axis indicates the sound pressure level. In FIG. 4A, it can be seen that high-frequency resonance occurs at 10 [KHz], the sound pressure level decreases at a frequency higher than that, and a sufficient level of sound is not reproduced. On the other hand, FIG. 4B is a diagram illustrating a result of analyzing and calculating a sound pressure frequency characteristic of the speaker according to Embodiment 1 by FEM. In FIG. 4B, it can be seen that resonance does not occur in the high frequency range, and sound can be reproduced up to a higher frequency than in FIG. 4A.

  As shown in FIGS. 4A and 4B, according to the first embodiment, by providing the groove 103 in the diaphragm 101, the rigidity of the diaphragm 101 can be increased and the high-frequency resonance frequency can be increased. it can. In particular, in the elongated diaphragm as shown in FIG. 1, resonance tends to occur in the major axis direction. However, by providing the diaphragm 103 with the groove 103, the resonance can be suppressed. In other words, according to the first embodiment, it is possible to obtain a sufficient reproduction sound quality even in an elongated speaker. Specifically, the applicant of the present application is a speaker having an elongated structure using an elongated diaphragm having a length of 50.8 [mm] and a width of 7 [mm] (the size of the speaker is 63 [mm] in length and 11 in width). [Mm]) was created, and it was confirmed that sufficient reproduction sound quality was obtained in the speaker.

  Furthermore, according to the first embodiment, by providing the groove 103 in the diaphragm 101, the position where the voice coil 105 is bonded to the diaphragm 101 can be determined easily and accurately. Here, the voice coil 105 is preferably arranged at a position where the magnetic flux density by the magnetic circuit 110 is high, and needs to be accurately attached to the position. According to the first embodiment, since the groove 103 plays a role of defining the mounting position of the voice coil 105, the voice coil 105 can be accurately arranged at an appropriate position of the diaphragm 101. Furthermore, since the variation in the mounting position of the voice coil 105 for each speaker can be reduced, the variation in the reproduction sound pressure level for each speaker can be reduced.

  2 and 3, the voice coil 105 is configured by two layers in the height direction (the vibration direction of the diaphragm 101), but the voice coil 105 may be configured by one or more layers. .

(Embodiment 2)
Next, a speaker according to Embodiment 2 will be described. FIG. 5 is a cross-sectional view in the minor axis direction of the speaker according to the second embodiment. The speaker according to the second embodiment has the same appearance as the speaker according to the first embodiment, and the plan view of the speaker is the same as FIG. FIG. 5 corresponds to FIG. 3 in the first embodiment. In FIG. 5, the same reference numerals are used for the same components as those in FIGS. Hereinafter, the speaker according to the second embodiment will be described focusing on differences from the speaker according to the first embodiment.

  Also in the second embodiment, the voice coil 105 is bonded to the bottom of the groove 103 of the diaphragm 101 as in the first embodiment. Here, in the second embodiment, the adhesive 201 is formed in a fillet shape on the side surface of the voice coil 105. That is, in addition to the bottom surface of the voice coil 105 (contact surface with the diaphragm 101), the adhesive 201 is also formed on the side surface. According to the second embodiment, the adhesive strength between diaphragm 101 and voice coil 105 can be further increased. In the third to seventh embodiments described later, the adhesive may be formed in a fillet shape.

(Embodiment 3)
Next, a speaker according to Embodiment 3 will be described. 6 and 7 are diagrams showing a loudspeaker according to Embodiment 3. FIG. That is, FIG. 6 is a plan view of the speaker, and FIG. 7 is a sectional view (E-F sectional view) in the minor axis direction of the speaker. 6 and 7, the same reference numerals are used for the same components as in FIGS. Hereinafter, the speaker according to the third embodiment will be described focusing on differences from the speaker according to the first embodiment.

  In the third embodiment, a plurality of protrusions 301 are provided at the bottom of the groove 103 of the vibration plate 101. The size (height or width) of the protrusion 301 is preferably smaller than the wire diameter of the voice coil 105. The protrusions 301 may be regularly arranged on the bottom of the groove 103 or may be irregularly arranged. Further, the protrusion 301 may be convex on the upper surface side of the diaphragm 101 or may be convex on the lower surface side. According to the third embodiment, since the contact area between the adhesive 106 and the diaphragm 101 is increased by the protrusions 301, the adhesive strength between the diaphragm 101 and the voice coil 105 can be further increased.

  In the third embodiment, a rib 302 may be provided at the bottom of the groove 103 instead of the protrusion 301. FIG. 8 is a plan view of a speaker according to a modification of the third embodiment. In FIG. 8, the rib 302 is provided in a direction perpendicular to the winding direction of the voice coil 105. Providing such a rib 302 on the diaphragm 101 can provide the same effects as when the protrusion 301 is provided on the diaphragm 101.

  In the fourth to seventh embodiments described later, the vibration plate 101 may be provided with the protrusions 301 or the ribs 302.

(Embodiment 4)
Next, a speaker according to Embodiment 4 will be described. FIG. 9 is a cross-sectional view of the speaker according to Embodiment 4 in the minor axis direction. The speaker according to the fourth embodiment has the same appearance as the speaker according to the first embodiment, and the plan view of the speaker is the same as FIG. FIG. 9 corresponds to FIG. 3 in the first embodiment. In FIG. 9, the same reference numerals are used for the same components as those in FIGS. Hereinafter, the speaker according to the fourth embodiment will be described focusing on differences from the speaker according to the first embodiment.

  In FIG. 9, a polymer film 401 is fixed to the surface of the voice coil 105 on the side opposite to the adhesive surface with the diaphragm 101. The polymer film 401 is fixed to the planar portion of the diaphragm 101 and the voice coil 105 so as to cover the voice coil 105. As shown in FIG. 9, the fourth embodiment has a configuration in which the voice coil 105 is sandwiched between the polymer film 401 and the groove 103. Therefore, the adhesive strength between the voice coil 105 and the diaphragm 101 can be further increased.

  In Embodiment 4, the film 402 on which the metal foil 403 is deposited may be used instead of the polymer film 401 (see FIG. 10). In addition, as the metal foil 403, it is preferable to use aluminum foil, copper foil, etc. excellent in thermal conductivity. According to this, the same effect as the case where the polymer film 401 is provided can be obtained, and the heat conduction performance of the film can be improved, thereby preventing the voice coil 105 from increasing in temperature and improving the input resistance performance. be able to. Furthermore, instead of the polymer film 401, only metal foil may be used.

(Embodiment 5)
Next, a speaker according to Embodiment 5 will be described. FIG. 11 is a cross-sectional view of the speaker according to Embodiment 5 in the minor axis direction. The speaker according to the fifth embodiment has the same appearance as the speaker according to the first embodiment, and the plan view of the speaker is the same as FIG. FIG. 11 corresponds to FIG. 3 in the first embodiment. In FIG. 11, the same reference numerals are used for the same components as those in FIGS. Hereinafter, the speaker according to the fifth embodiment will be described focusing on differences from the speaker according to the first embodiment.

  In the fifth embodiment, instead of the polymer film 401 in the fourth embodiment, a rubber sheet 501 having viscoelasticity is fixed to the planar portion of the diaphragm 101 and the voice coil 105. That is, in the fifth embodiment, the voice coil 105 is sandwiched between the rubber sheet 501 and the groove 103. With this configuration, as in the fourth embodiment, the adhesive strength between the voice coil 105 and the diaphragm 101 can be further increased. Furthermore, in the fifth embodiment, since the rubber sheet 501 having viscoelasticity is used, unnecessary resonance of the voice coil 105 can be prevented by the internal loss of the rubber sheet 501. Therefore, the distortion at the time of vibration of the diaphragm 101 can be further reduced.

  In the fifth embodiment, instead of the rubber sheet 501, a viscoelastic polymer sheet, rubber foam, or polymer foam may be used. By using these viscoelastic materials, the same effects as when the rubber sheet 501 is used can be obtained. Further, a viscoelastic film 502 formed on the surface of the voice coil 105 may be used instead of the rubber sheet 501 (see FIG. 12). Specifically, a thin viscoelastic film 502 can be formed on the surface of the voice coil 105 by applying a liquid viscoelastic body on the voice coil 105 and then drying it. The material of the viscoelastic film is preferably a polymer with a large internal loss (for example, a rubber material such as NBR or SBR dissolved in a solvent), a water-soluble emulsion type adhesive, or modified silicon. . By using the viscoelastic film 502, the same effect as when the rubber sheet 501 is used can be obtained. In FIG. 12, the adhesive 201 is formed in a fillet shape on the side surface of the voice coil 105, but may not be formed in a fillet shape.

(Embodiment 6)
Next, a speaker according to Embodiment 6 will be described. FIG. 13 is a cross-sectional view of the speaker according to Embodiment 6 in the minor axis direction. The speaker according to the sixth embodiment has the same appearance as the speaker according to the first embodiment, and the plan view of the speaker is the same as FIG. FIG. 13 corresponds to FIG. 3 in the first embodiment. In FIG. 13, the same reference numerals are used for the same components as in FIGS. Hereinafter, the speaker according to the sixth embodiment will be described focusing on differences from the speaker according to the first embodiment.

  In the sixth embodiment, the voice coil 105 is bonded to the bottom of the groove 103 via the buffer material 601. That is, the buffer material 601 is bonded to the groove 103, and the voice coil 105 is bonded to the buffer material 601. The buffer material 601 may be made of a sheet material having excellent heat resistance such as paper or polyimide, or may be made of a highly viscoelastic sheet material such as rubber. According to the sixth embodiment, the vibration of the voice coil 105 is transmitted to the diaphragm 101 via the shock absorber 601 by disposing the shock absorber 601 having a braking effect between the voice coil 105 and the diaphragm 101. It will be. That is, unnecessary resonance of the voice coil 105 is suppressed by the internal loss of the buffer material 601, and the sound quality of the speaker can be improved. Further, when a high heat-resistant sheet material is used as the buffer material 601, the heat generated by the voice coil 105 is hardly transmitted to the diaphragm 101, so that the durability of the speaker can be improved.

  In the sixth embodiment, the configurations shown in the fourth or fifth embodiment may be further combined. That is, in the sixth embodiment, the surface of the voice coil 105 on the opposite side of the adhesive surface with the diaphragm 101 may be fixed to the film shown in the fourth and fifth embodiments.

(Embodiment 7)
Next, a speaker according to Embodiment 7 will be described. 14 is a plan view of the speaker, FIG. 15 is a sectional view in the major axis direction (GH sectional view) of the speaker, and FIG. 16 is a sectional view in the minor axis direction of the speaker (IJ sectional view). ). 14 to 16, the same reference numerals are used for the same components as those in FIGS. Hereinafter, the speaker according to the seventh embodiment will be described focusing on differences from the speaker according to the first embodiment.

  In the seventh embodiment, instead of the substantially planar diaphragm 101, a diaphragm 701 having an arched cross section along the major axis direction is used. An edge 702 is annularly provided on the outer peripheral portion of the diaphragm 701. The edge 702 has a substantially semicircular cross section like the edge 102 of the first embodiment. The outer periphery of the edge 702 is connected to the frame 104 and the yoke 107.

  As shown in FIG. 15, the cross section of the diaphragm 701 has an arch shape in which the central portion is higher than the end portion. The arch shape of the diaphragm 701 is configured in a range equal to or less than the height of the edge 702. The seventh embodiment is the same as the first embodiment except that the cross section of the diaphragm 701 has an arch shape. That is, the diaphragm 701 is provided with a groove 703 similar to the groove 103 of the first embodiment. The voice coil 105 is bonded to the bottom of the groove 703.

  According to the seventh embodiment, the bending rigidity of the diaphragm can be increased by forming the cross section of the diaphragm 701 in an arch shape. As a result, the high-band resonance frequency can be increased, so that the reproduction band of the speaker can be expanded. That is, it is possible to provide a speaker that can reproduce a higher quality sound. Further, since the height of the arch shape of the diaphragm 701 is equal to or less than the height of the edge 702, the diaphragm 701 does not affect the thickness of the entire speaker. That is, the thickness of the speaker does not increase even if the diaphragm is arched.

  The seventh embodiment has a configuration in which the loudspeaker diaphragm 101 according to the first embodiment is an arch-shaped diaphragm 701. However, the loudspeaker diaphragm 101 according to the second to sixth embodiments is used. The diaphragm 701 may be used.

  The speaker according to the present invention can realize reproduced sound with less distortion, and is useful as a speaker used in various audio devices, particularly video audio devices. It can also be used for sound reproduction in portable terminals and the like.

Plan view of speaker according to Embodiment 1 Sectional drawing of the major axis direction of the speaker which concerns on Embodiment 1. FIG. Sectional drawing of the short axis direction of the speaker which concerns on Embodiment 1. FIG. The figure which shows the sound pressure frequency characteristic of the conventional speaker The figure which shows the sound pressure frequency characteristic of the speaker which concerns on Embodiment 1. FIG. Sectional drawing of the minor axis direction of the speaker which concerns on Embodiment 2. FIG. Plan view of speaker according to Embodiment 3. Sectional drawing of the minor axis direction of the speaker which concerns on Embodiment 3. FIG. A plan view of a speaker according to a modification of the third embodiment Sectional drawing of the minor axis direction of the speaker which concerns on Embodiment 4. FIG. Sectional drawing of the short diameter direction of the speaker which concerns on the modification of Embodiment 4. FIG. Sectional view of minor axis direction of speaker according to Embodiment 5 Sectional drawing of the breadth direction of the speaker which concerns on the modification of Embodiment 5 Sectional drawing of the breadth direction of the speaker concerning Embodiment 6 Plan view of speaker according to Embodiment 7. Sectional drawing of the major axis direction of the speaker which concerns on Embodiment 7 Sectional view of minor axis direction of speaker according to Embodiment 7 Plan view of a conventional slender speaker Sectional view in the major axis direction of a conventional slender speaker Sectional view in the minor axis direction of a conventional slender speaker

Explanation of symbols

101, 701 Diaphragm 102, 702 Edge 103, 703 Groove 104 Frame 105 Voice coil 106, 201 Adhesive 107 York 108 Magnet 109 Top plate 301 Protrusion 302 Rib 401 Polymer film 402 Film 403 Metal foil 501 Rubber sheet 502 Viscoelastic film 601 cushioning material

Claims (10)

A horizontally or vertically elongated diaphragm having a groove having a concave cross section;
An edge connected to the outer periphery of the diaphragm and having a substantially semicircular cross section;
A voice coil bonded to the groove,
The voice coil is thicker than the depth of the groove,
The voice coil has a cross section in which the length in the direction along the surface of the diaphragm is longer than the length in the direction perpendicular to the surface of the diaphragm.   The speaker according to claim 1, wherein an adhesive that bonds the voice coil and the diaphragm is formed in a fillet shape on a side surface of the voice coil.   The speaker according to claim 1, wherein a plurality of protrusions smaller than a wire diameter of the voice coil are provided on an adhesive surface between the groove and the voice coil.   The speaker according to claim 1, wherein a cross section along the longitudinal direction of the diaphragm has an arch shape lower than the edge. A horizontally or vertically elongated diaphragm having a groove having a concave cross section;
An edge connected to the outer periphery of the diaphragm and having a substantially semicircular cross section;
A voice coil bonded to the groove;
A speaker comprising: the diaphragm and a film fixed to the voice coil so as to cover the voice coil on the opposite side of the bonding surface between the voice coil and the diaphragm.   The speaker according to claim 5, wherein the film is formed of any one of a polymer film, a polymer film on which a metal foil is deposited, and a metal foil.   The speaker according to claim 5, wherein the film is made of a material having viscoelasticity.   The speaker according to claim 5, wherein a cross section along the longitudinal direction of the diaphragm has an arch shape lower than the edge. A horizontally or vertically elongated diaphragm having a groove having a concave cross section;
An edge connected to the outer periphery of the diaphragm and having a substantially semicircular cross section;
A planar cushioning material bonded to the groove;
A speaker comprising: a voice coil bonded to the groove via the buffer material. The speaker according to claim 9, wherein a cross section along the longitudinal direction of the diaphragm has an arch shape lower than the edge.

Images