JP2008066959A - Loudspeaker, manufacturing method for loudspeaker diaphragm, and manufacturing method for voice coil cover - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure sufficient plane rigidity and to control the warp, without damaging a mold working property and a mass-producing property by a press-heating molding. <P>SOLUTION: A loudspeaker has a laminated sheet 33 comprised of a wooden sheet 29 cut into a plate in a sheet shape from a wood 27 having a grain and of a reinforcing sheet 31 laminated to one surface of the wood sheet 29, and is provided with a combinational diaphragm of a cross-sectional lamination structure laminating a first diaphragm 23 and a second diaphragm 25 made in a cone shape in advance by the laminated sheet 33 in order of the wooden sheet 29, the reinforcing sheet 31, the reinforcing sheet 31 and the wooden sheet 29. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a speaker using natural wood, a diaphragm for the speaker, and a method for manufacturing a voice coil cover.

  In recent years, a speaker using a natural tree as a material for a diaphragm of a speaker is known.

  The reason for using wood as the material of the diaphragm is that the natural sound that wood originally has can be obtained, and the appearance can be improved and the effect of giving a high quality feeling can be obtained. It is attracting attention as one of the materials.

  On the other hand, there are many problems just by dealing with natural wood, especially the strength of the wooden sheet and the measures against warping.

  For example, when the wooden sheet 103 is cut into a sheet form from the log-like tree 101 cut out as shown in FIG. 8, the wooden sheet 105 (outside the center of the tree) and the tree back 107 are used. (Inward with respect to the center of the tree), and warpage occurs toward the tree surface 105 as time passes.

Therefore, as shown in Patent Document 1, a laminated sheet in which a reinforcing sheet 101 such as a nonwoven fabric or Japanese paper is pasted on the wood back surface 107 of the wooden sheet 103 in order to keep the warpage small and ensure the surface rigidity of the wooden sheet 103. Measures are taken.
JP-A-10-304492

  The laminated sheet is made into a conical diaphragm, for example, by press thermoforming, but the wooden sheet 103 cannot be made thicker than necessary when considering the surface of molding by press thermoforming and the mass productivity. is the current situation.

  Generally, depending on the aperture of the diaphragm, 0.1 mm is used for thin and 0.6 mm is used for thick, and means to suppress surface rigidity and warpage by using a laminated sheet Is adopted. However, since warpage still occurs, sufficient warping measures have been required.

  As one of the solutions, JP-A-5-83792 discloses a plurality of composite sheets composed of sliced wood and a non-woven fabric made of an adhesive resin attached to the back of the sliced wood. A method of laminating and molding into a curved surface shape, and softening the composite sheet, laminating at least two composite sheets that have been softened, and then heating and pressing to form an acoustic diaphragm A method of manufacturing is disclosed. In this method, when molding a thick wooden diaphragm, a plurality of composite sheets composed of thin wood and a non-woven fabric made of an adhesive resin affixed to the back surface are laminated to a predetermined thickness, and curved surface This is a method of forming a cone shape while preventing cracking during molding. However, if the composite sheet is laminated and bonded before the curved surface molding, the amount of strain applied to the curved surface of the wood varies depending on the position of the layer (for example, the inner and outer wood layers of the cone shape). Even if it is a composite sheet, as the thickness increases, the laminated adhesive surface may be distorted, which may cause cracking. Further, since the restoring force that tends to return to the original force after molding is easily applied to the strain force, the curved surface shape may be deformed with time.

  FIG. 9A is a plan view of a conical diaphragm, FIG. 9B is an initial state of XX ′ and YY ′, and FIG. 9C is one composite sheet. XX ', Y-Y' composite sheet at the time of showing the change over time by crossing the grain 90 degrees, but molded into a curved shape with one composite sheet composed of wood and nonwoven fabric In the case of the diaphragm, the direction of the wood fibers is directed in one direction. Therefore, if the resin impregnation is insufficient, for example, as shown in (c), only one direction of either x or y is deformed over time. There is also a case where it ends up. Further, in the above-mentioned Japanese Patent Application Laid-Open No. 5-83792, when the mechanical strength of the diaphragm 5 is desired to be increased, the direction of the wood fibers of the composite sheet 4 is laminated so as to intersect 90 ° vertically and horizontally. However, if composite sheets made of wood and nonwoven fabric are laminated in the same order, the deformation force is dispersed when the directions of the wood fibers are crossed, as shown in (d), There may be cases where deformation occurs evenly in the x and y directions.

  Therefore, in the present invention, a speaker that is excellent in appearance and without sacrificing molding processability and mass productivity by press thermoforming, and can secure sufficient surface rigidity and suppress warpage, It is an object of the present invention to provide a method for manufacturing a speaker diaphragm and a method for manufacturing a voice coil cover.

  In order to achieve the above object, according to a first aspect of the present invention, a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface thereof is oriented in a direction in which the reinforcing sheet is an inner peripheral surface. A first diaphragm formed into a substantially conical shape, and a second diaphragm formed into a substantially conical shape in a direction in which the reinforcing sheet becomes an outer peripheral surface are in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet. It is characterized by comprising a diaphragm having a laminated structure formed by being superimposed.

  Second, the reinforcing sheet is formed by superimposing both ends of a notch opening cut out in a V shape toward the center on a part of a laminated sheet obtained by bonding a reinforcing sheet to a wooden sheet made of natural wood. A step of forming a substantially conical first diaphragm in the direction of the inner peripheral surface, and a substantially conical shape by superimposing both ends of the notched opening of the bonded sheet in the direction of the outer peripheral surface of the reinforcing sheet. A step of forming a second diaphragm having a shape, and the substantially diaphragm-shaped first diaphragm and the second diaphragm were laminated in the order of wooden sheet, reinforcing sheet, reinforcing sheet, and wooden sheet by press thermoforming. The method includes the step of producing a speaker diaphragm having a substantially trumpet-shaped laminated structure.

  Third, the first diaphragm and the second diaphragm made of a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface of the wooden sheet, the reinforcing sheet, and the reinforcement It is characterized by comprising a diaphragm having a laminated structure in which a sheet and a wooden sheet are laminated in order and formed into a substantially dome shape.

  Fourth, a first diaphragm in which a bonded sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface thereof is formed in a substantially dome shape so that the reinforcing sheet becomes an inner peripheral surface. And a second diaphragm in which the bonded sheet is formed in a substantially dome shape in a direction in which the reinforcing sheet becomes an outer peripheral surface, and is laminated in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet. A diaphragm having a laminated structure is formed.

  5thly, the 1st diaphragm and 2nd diaphragm which consist of a bonding sheet | seat which has the wooden sheet | seat which consists of natural wood, and the reinforcement sheet | seat bonded together on the one surface are a wooden sheet | seat, a reinforcement sheet | seat, reinforcement A voice coil cover having a laminated structure in which a sheet and a wooden sheet are stacked in order and formed into a substantially dome shape is provided.

  6thly, the 1st diaphragm which shape | molded the bonding sheet | seat which has the wooden sheet | seat which consists of natural wood, and the reinforcement sheet bonded together on the one surface in the direction where the said reinforcement sheet | seat becomes an internal peripheral surface. And a second diaphragm in which the bonded sheet is formed in a substantially dome shape in a direction in which the reinforcing sheet becomes an outer peripheral surface, and is laminated in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet. A voice coil cover having a laminated structure is formed.

  Seventh, the first diaphragm and the second diaphragm made of a laminated sheet obtained by laminating a reinforcing sheet to a wooden sheet made of natural wood are pressed into a wooden sheet, a reinforcing sheet, and a reinforcing sheet. And a step of producing a speaker diaphragm having a laminated structure in which a wooden sheet is superposed in the order of a dome shape.

  Eighth, a first vibration plate and a second vibration plate made of a laminated sheet obtained by bonding a reinforcing sheet to a wooden sheet made of natural wood are pressed and heated to form a wooden sheet, a reinforcing sheet, and a reinforcing sheet. And a step of making a voice coil cover having a laminated structure in which a wooden sheet is superposed in order and having a substantially dome shape.

  Ninth, forming a first diaphragm by forming a bonded sheet obtained by bonding a reinforcing sheet to a wooden sheet made of natural wood into a substantially dome shape in a direction in which the reinforcing sheet becomes an inner peripheral surface; The step of forming the second diaphragm by forming the bonded sheet into a substantially dome shape so that the reinforcing sheet becomes the outer peripheral surface, and the first diaphragm and the second diaphragm are made of wood by press thermoforming. And a step of producing a speaker diaphragm having a laminated structure in a substantially dome shape in which a sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet are stacked in this order.

  Tenth, a step of forming a first diaphragm by forming a laminated sheet obtained by bonding a reinforcing sheet to a wooden sheet made of natural wood into a substantially dome shape in a direction in which the reinforcing sheet becomes an inner peripheral surface; The step of forming the second diaphragm by forming the bonded sheet into a substantially dome shape so that the reinforcing sheet becomes the outer peripheral surface, and the first diaphragm and the second diaphragm are made of wood by press thermoforming. And a step of making a combined voice coil cover having a laminated structure in which a sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet are stacked in order in a substantially dome shape.

  In the first and second loudspeaker and the method of manufacturing the diaphragm according to the present invention, the first diaphragm and the second diaphragm made in advance in a conical shape are superposed on each other, and the combined vibration of the laminated structure is performed. Since it is made into a board, since it becomes difficult to generate | occur | produce a distortion | strain on a joint bonding surface, it can use as a speaker for middle sounds and a low sound while ensuring the surface rigidity of a whole diaphragm and suppressing curvature reliably.

  In addition, it is possible to make a diaphragm for medium and low sounds without impairing moldability and mass productivity. In addition, since the first and second diaphragms made in a conical shape are overlapped, a wooden sheet with a thin plate thickness can be used about half of the conventional one. Warm molding can be obtained and the warpage can be reliably suppressed while improving the appearance by the wood sheet having both sides of wood grain.

  In the third and fourth loudspeakers of the present invention, since the combination diaphragm having a laminated structure in which the first and second diaphragms previously formed in a dome shape are overlapped, both sides are wood-tone. While improving the appearance with the wooden sheet, it is possible to ensure the surface rigidity of the entire diaphragm and to prevent warping, and it can be used as a loudspeaker.

  In the speakers according to the fifth and sixth aspects of the present invention, the surface rigidity can be ensured and warping can be reliably suppressed while improving the appearance of the voice coil cover by the wood sheet having both sides of the wood grain.

  Further, in the seventh to tenth speaker diaphragm and voice coil cover manufacturing methods of the present invention, the first and second diaphragms made in advance in a dome shape are overlapped by press thermoforming. Since it can be made into a laminated structure, a diaphragm and a voice coil cover for high sounds can be respectively produced without impairing moldability and mass productivity. In addition, it is possible to ensure the overall surface rigidity and reliably suppress warpage while improving the appearance of the diaphragm and the voice coil cover by the wood sheet having both sides of wood grain.

  Hereinafter, the first embodiment of the present invention will be specifically described with reference to FIGS. 1 to 4.

  FIG. 1 shows a loudspeaker used for middle and low sounds according to the present invention. The speaker 1 includes a diaphragm 5 disposed in a housing 3, a voice coil 7 provided at a central portion of the diaphragm 5, and a diaphragm driving device 9 that drives the diaphragm 5 via the voice coil 7. And have.

  The outer peripheral edge of the diaphragm 5 is fixedly supported by the housing 3 via an elastically deformable rubber edge 11 mounted over the entire peripheral edge and an annular arrow paper 13 that suppresses the end of the rubber edge 11. The voice coil 7 is covered by a voice coil cover 15 and supported by the housing 3 via a damper 17 that is disposed and fixed at the central portion of the diaphragm 5 and is movable. The diaphragm drive device 9 is composed of a magnetic circuit part 19 with a pole 19a facing the voice coil 7 and a donut-shaped magnet 21 attached to the magnetic circuit part 19, and the magnet is based on an input signal from outside the figure. 21 gives a driving force in the direction of the arrow to the voice coil 7.

  On the other hand, the diaphragm 5 is a combination diaphragm having a laminated structure in which a first diaphragm 23 and a second diaphragm 25 are overlapped as shown in FIGS. It has a conical section for use in

  As shown in FIG. 6, the first and second diaphragms 23 and 25 are made of non-woven fabric or Japanese paper on one surface of a wooden sheet 29 that has been formed into a sheet shape from a log-like wood 27 that is a natural wood. The reinforcing sheet 31 is made of a bonded sheet 33 bonded together.

  When the wooden sheet 29 is made into a sheet shape from the log-shaped tree 27, for example, a thin sheet having a thickness of 0.05 mm, which is about half the conventional one, and a thick sheet having a thickness of 0.6 mm are used. Yes.

  As shown in FIGS. 2 and 3, the overlapping directions of the first and second diaphragms 23 and 25 formed in a conical shape in advance by the bonding sheet 33 are a wooden sheet 29, a reinforcing sheet 31, a reinforcing sheet 31, and a wooden sheet. The order is the sheet 29.

  Next, a method for manufacturing the diaphragm of the speaker 1 will be described with reference to FIG.

  First, a sheet-like wooden sheet 29 is made by slicing from the cut-out tree 27 (1-a, 1-b). At this time, the thickness of the wooden sheet 29 differs depending on the diameter of the diaphragm 5, but the thin one is about 0.05 mm, which is about half of the conventional thickness, and the thick one is 0.6 m like the conventional one. Then, a reinforcing sheet 31 such as a non-woven fabric or Japanese paper is pasted on one surface to make a bonded sheet 33 (1-d).

  Next, after providing a V-shaped cutout opening 35 in a part of the laminated sheet 33, the first diaphragm 23 in a state in which both end portions 35a and 35b of the cutout opening 35 are overlapped and temporarily fixed, 2 is immersed in a solution 37 containing a lubricant (or penetrant) (1-e, 1-f). The first diaphragm 23 is temporarily fixed so that the wood surface comes to the conical inner surface, and the second diaphragm 25 is temporarily fixed so that the wood surface comes to the conical outer surface. As a result, the first diaphragm 23 and the second diaphragm 25 become soft, so that the first and second diaphragms 23 and 25 are provided with a male mold 41 and a female mold 43 provided with heating means such as a heater 39. Are set in a press machine 45 and are temporarily formed separately. Thereafter, the temporarily molded first and second diaphragms 23 and 25 are impregnated with a thermosetting resin, and the first and second diaphragms 23 and 25 are made of a wooden sheet 29, a reinforcing sheet 31, and a reinforcing member. Overlay so that it becomes a combination of sheet 31 and wooden sheet 29 and set again in the press machine, and the two diaphragms are laminated and bonded with thermosetting resin, and the entire diaphragm is solidified with thermosetting resin and curved shape (1-g).

  When the wooden sheet is as thin as about 0.1 to 0.2 mm, it is not always necessary to soak it in a lubricant and soften it. In that case, first and second diaphragms 23 and 25 are directly impregnated with thermosetting resin, and these are stacked in the order of wooden sheet, reinforcing sheet, reinforcing sheet, and wooden sheet, and set in the press machine. Then, it may be hardened with a thermosetting resin by hot pressing and curved-surface molded.

  Next, a conical diaphragm 5 for intermediate sound or low sound completed is obtained by processing the outer diameter of the diaphragm 5 after completion of pressing and opening a hole 47 for voice coil in the center (1- h).

  The diaphragm 5 made for medium sound or bass is a combined diaphragm having a laminated structure in which the wooden sheet 29, the reinforcing sheet 31, the reinforcing sheet 31, and the wooden sheet 29 are sequentially laminated. Ensuring rigidity and warping can be reliably suppressed. Moreover, the wood sheet 29 with grain is arranged on the inner side and the outer side, which is very preferable in terms of appearance quality. As described above, since the first and second diaphragms 23 and 25 are laminated and bonded in advance after being deformed into curved surfaces, the strain on the two laminated surfaces is reduced and the shape is likely to be stable.

  Furthermore, since the first and second diaphragms 23 and 25 are laminated facing the opposite surfaces (inner side and outer side), if they are formed with the wood fibers oriented in the same direction, the front and back strains The directions are offset, the shape is stabilized, and the diaphragm can be prevented from being distorted due to changes with time.

  FIG. 5 shows a second embodiment of a loudspeaker 1-A in which a diaphragm 49 is formed in a dome-shaped cross section.

  The diaphragm 49 is a combination diaphragm having a laminated structure in which the first diaphragm 23 and the second diaphragm 25 are overlapped, which is the same as in the first embodiment, and the difference is a conical shape. It is a point formed in the shape of a cross-sectional dome used for high sound.

  As shown in FIG. 7, the first and second diaphragms 23, 25 are reinforcing sheets made of nonwoven fabric or Japanese paper on one surface of a wooden sheet 29 that has been cut into a sheet form from a wood 27 having a log-like grain. It is made of a bonding sheet 33 in which 31 is bonded.

  When the wooden sheet 29 is made into a sheet shape from the log-shaped tree 27, for example, a thin sheet having a thickness of 0.05 mm, which is about half the conventional one, and a thick sheet having a thickness of 0.6 mm are used. Yes.

  As shown in FIG. 6, the overlapping direction of the first and second diaphragms 23 and 25 formed by the bonding sheet 33 is in the order of the wooden sheet 29, the reinforcing sheet 31, the reinforcing sheet 31, and the wooden sheet 29. Yes.

  The high-frequency speaker 1-A has the diaphragm driving device 9 provided in the housing 3 outside the diaphragm 49, which is the same as in the first embodiment.

  Next, a method for manufacturing the diaphragm of the speaker 1 will be described with reference to FIG.

  First, a sheet-like wooden sheet 29 is made by slicing from a log 27 which is a natural wood log (1-a, 1-b). At this time, the thickness of the wooden sheet 29 differs depending on the diameter of the diaphragm 5, but the thin one is about 0.05 mm, which is about half of the conventional thickness, and the thick one is 0.6 mm like the conventional one. Then, a reinforcing sheet 31 such as a non-woven fabric or Japanese paper is pasted on one surface to make a bonded sheet 33 (1-d).

  Next, the first diaphragm 23 and the second diaphragm 25 made by the bonding sheet 33 are immersed in a solution 37 containing a lubricant (or penetrant) (1-e, 1-f). As a result, the first diaphragm 23 and the second diaphragm 25 are softened. Therefore, the first and second diaphragms 23 and 25 are set in a press machine equipped with heating means such as a heater 39 and separately. Temporarily mold into a dome shape. At that time, the first diaphragm 23 is temporarily molded so that the wood surface comes to the dome surface, and the second diaphragm 25 is temporarily molded so that the wood surface comes to the back surface of the dome (1-g). Thereafter, the temporarily molded first and second diaphragms 23 and 25 are impregnated with a thermosetting resin, and the first diaphragm 23 and the second diaphragm 25 are made of a wooden sheet, a reinforcing sheet, Overlay the reinforcing sheets and wooden sheets in this order, set them again in the press machine, and laminate and bond the two diaphragms with thermosetting resin. Stabilize.

  When the wooden sheet is as thin as about 0.1 to 0.2 mm, it is not always necessary to soak it in a lubricant and soften it. In that case, first and second diaphragms 23 and 25 are directly impregnated with thermosetting resin, and these are stacked in the order of wooden sheet, reinforcing sheet, reinforcing sheet, and wooden sheet, and set in the press machine. Then, it may be hardened with a thermosetting resin by hot pressing and curved-surface molded.

  Next, the diaphragm 49 formed in the cross-sectional dome shape for high sounds is obtained by performing the outer diameter process of the diaphragm 49 after completion of pressing (1-h).

  Since the diaphragm 49 made for high sound is a combined diaphragm having a laminated structure in which the wooden sheet 29, the reinforcing sheet 31, the reinforcing sheet 31, and the wooden sheet 29 are stacked in this order, the surface rigidity of the entire diaphragm can be ensured. Sled can be surely suppressed. Moreover, the wood sheet 29 with grain is arranged on the inner side and the outer side, which is very preferable in terms of appearance quality.

  On the other hand, the diaphragm 49 made for high sounds may be used as the voice coil cover 15 shown in FIG. Since the voice coil cover 15 vibrates during the operation of the speaker 1, the most suitable voice coil cover can be obtained by using the diaphragm 49 having a dome-shaped cross section as it is. In addition, it is not necessary to make a separate dedicated voice coil cover, which is very preferable in terms of cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cut explanatory view showing a first embodiment of a speaker using a diaphragm having a conical section according to the present invention. FIG. 3 is a schematic perspective view showing a superposition direction of a first diaphragm and a second diaphragm. Sectional explanatory drawing of a part of FIG. 2 made into the combination diaphragm. The outline explanatory view showing the process of making the diaphragm for conical speakers. Outline | summary cutting | disconnection explanatory drawing which showed 2nd Embodiment of the speaker using the diaphragm of a cross-sectional dome shape. Explanatory drawing which showed the combination cross section of the diaphragm of a cross-sectional dome shape. The outline explanatory view showing the process of making the diaphragm for speakers of a dome section. The schematic explanatory drawing which showed the state where a curvature generate | occur | produces when a wooden sheet | seat is boarded from a log-shaped tree. The outline explanatory view showing the state where the distortion of the conventional example appears.

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 ... Conical diaphragm 15 ... Voice coil cover 23 ... 1st diaphragm 25 ... 2nd diaphragm 27 ... Wood with wood 29 ... Wooden sheet 31 ... Reinforcement sheet 33 ... Laminated sheet 35 ... Notch opening 45 ... Pressing machine 49 ... Dome-shaped diaphragm

Claims (10)

  A first diaphragm in which a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface thereof is formed into a substantially conical shape in a direction in which the reinforcing sheet becomes an inner peripheral surface, and the reinforcing A laminated diaphragm having a second diaphragm formed in a substantially conical shape in a direction in which the sheet becomes an outer peripheral surface is laminated and formed in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet. The speaker characterized by having it.   The reinforcing sheet is overlapped with the inner peripheral surface by overlapping both ends of a notch opening cut out in a V shape toward the center on a part of a laminated sheet obtained by bonding a reinforcing sheet to a wooden sheet made of natural wood. Forming a substantially conical first diaphragm in such a direction, and overlapping the both ends of the notch opening portion of the bonded sheet in a direction in which the reinforcing sheet becomes an outer peripheral surface. The substantially conical shape of the first diaphragm and the second diaphragm in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet by press thermoforming. A method for manufacturing a speaker diaphragm, comprising a step of making a speaker diaphragm having a laminated structure.   The first diaphragm and the second diaphragm made of a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface of the wooden sheet, the reinforcing sheet, the reinforcing sheet, and the wooden sheet A loudspeaker comprising: a diaphragm having a laminated structure which is superposed in the order of and formed into a substantially dome shape.   A first diaphragm in which a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface thereof is formed in a substantially dome shape so that the reinforcing sheet becomes an inner peripheral surface, and the reinforcing A second diaphragm in which the laminated sheet is formed in a substantially dome shape in a direction in which the sheet becomes an outer peripheral surface is laminated in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet, and is formed into a substantially dome shape. A speaker having a laminated structure diaphragm.   The first diaphragm and the second diaphragm made of a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface of the wooden sheet, the reinforcing sheet, the reinforcing sheet, and the wooden sheet A speaker comprising a voice coil cover having a laminated structure, which is formed in a substantially dome shape by being superimposed in the order of.   A first diaphragm in which a laminated sheet having a wooden sheet made of natural wood and a reinforcing sheet bonded to one surface thereof is formed in a substantially dome shape so that the reinforcing sheet becomes an inner peripheral surface, and the reinforcing A second diaphragm in which the laminated sheet is formed in a substantially dome shape in a direction in which the sheet becomes an outer peripheral surface is laminated in the order of a wooden sheet, a reinforcing sheet, a reinforcing sheet, and a wooden sheet, and is formed into a substantially dome shape. A speaker comprising a voice coil cover having a laminated structure.   A first diaphragm and a second diaphragm made of a laminated sheet obtained by laminating a reinforcing sheet to a wooden sheet made of natural wood are pressed and heated to form a wooden sheet, a reinforcing sheet, a reinforcing sheet, or a wooden sheet. And a step of producing a speaker diaphragm having a laminated structure that is superposed in order to form a substantially dome shape.   A first diaphragm and a second diaphragm made of a laminated sheet obtained by laminating a reinforcing sheet to a wooden sheet made of natural wood are pressed and heated to form a wooden sheet, a reinforcing sheet, a reinforcing sheet, or a wooden sheet. And a step of producing a voice coil cover having a laminated structure in which a substantially domed shape is superposed in order.   Forming a first diaphragm by forming a laminated sheet in which a reinforcing sheet is bonded to a wooden sheet made of natural wood into a substantially dome shape so that the reinforcing sheet becomes an inner peripheral surface; and Forming the second diaphragm by forming the bonded sheet into a substantially dome shape in a direction to be a surface, and combining the first diaphragm and the second diaphragm by press thermoforming into a wooden sheet / reinforcing sheet A process for producing a speaker diaphragm having a laminated structure in a substantially dome shape in which a reinforcing sheet and a wooden sheet are stacked in this order.   Forming a first diaphragm by forming a laminated sheet in which a reinforcing sheet is bonded to a wooden sheet made of natural wood into a substantially dome shape so that the reinforcing sheet becomes an inner peripheral surface; and Forming the second diaphragm by forming the bonded sheet into a substantially dome shape in a direction to be a surface, and combining the first diaphragm and the second diaphragm by press thermoforming into a wooden sheet / reinforcing sheet A method of manufacturing a voice coil cover, comprising: a laminated voice coil cover having a laminated structure in which a reinforcing sheet and a wooden sheet are superposed in order and formed into a substantially dome shape.

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