JP2007221762A - Diaphragm for electroacoustic transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaphragm for an electroacoustic transducer employing a wooden sheet, which can prevent the generation of a break on the wooden sheet in a mold during press hot molding and prevent burning of a lubricant on the mold during press hot molding. <P>SOLUTION: A laminated sheet is formed by laminating a sheet member of the material different from that of the wooden sheet on at least one surface of a single wooden sheet. This laminated sheet is immersed in an aqueous solution containing a penetrating agent or an aqueous solution containing a penetrating agent and a wetting agent, and is molded into a predetermined shape as a diaphragm by press hot molding. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electroacoustic transducer diaphragm.

  Loudspeaker diaphragms using wooden sheets can reproduce more natural sounds than loudspeaker diaphragms using paper pulp or plastic, but break when press-molded into diaphragm shapes. There is a technical problem that it is easy to do, and what is disclosed in the following Patent Document 1 has been proposed as a solution to this problem.

The speaker diaphragm is prepared by preparing a solution containing a lubricant, immersing a bonded sheet in which a nonwoven fabric or paper is bonded to at least one surface of a single wooden sheet in the solution, and then bonding the bonded sheet. Is formed into a predetermined shape by press thermoforming, and the wooden sheet is impregnated with a lubricant to give the wooden sheet smoothness and suppleness, making it difficult to break during press thermoforming.
JP-A-10-304492

  However, in the conventional speaker diaphragm described above, it is not possible to say that the wooden sheet slips or stretches at the time of press heat forming. Therefore, the wooden sheet is still broken in the mold at the time of press heat forming.

  Further, there has been a problem that the lubricant oozes out on the surface of the wooden sheet during press-heating and seizes into the mold, making it difficult for the wooden sheet to peel off from the mold.

  In addition, there is a problem in that the lubricant baked onto the mold is partially peeled off and becomes a small piece that adheres to the diaphragm-shaped molded product and impairs the appearance.

  Furthermore, since the work of peeling the seizure of the lubricant from the speaker diaphragm is required, there is a problem that productivity is lowered.

  An object of the present invention is to provide a diaphragm for an electroacoustic transducer that can eliminate the above-mentioned problems.

  In order to achieve the above object, the diaphragm for an electroacoustic transducer according to the present invention is a bonded sheet in which a sheet member made of a material different from a wooden sheet is bonded to at least one surface side of a single wooden sheet, and is an interface. A bonded sheet containing an aqueous solution containing at least a penetrant among a penetrant and a wetting agent as an activator is formed into a predetermined shape by press heat molding.

  The penetrant used in the present invention includes, for example, lauryl sulfate ester salt, dialkylsulfosuccinate ester salt, fatty acid amide sulfonate, alkylnaphthalene sulfonate, alkylphenol ethylene oxide adduct, medium to higher alcohol ethylene oxide adduct, It shall contain at least one butyl oleate and others.

  The wetting agent includes, for example, monohydric alcohol, dihydric alcohol, trihydric alcohol, ethylene glycols, butyl glycols, propyl glycols, saccharides, mucopolysaccharides, sugar alcohols, water-soluble various proteins, etc. Including at least two.

  In addition, about the use density | concentration of a penetrating agent, although the penetration effect with respect to wood is acquired at 0.001 weight% or more, it is 0.1 weight% or more that the penetration effect is acquired stably. In addition, since the penetrant remains in the wooden sheet and affects the durability of the diaphragm, it is desirable that the concentration of penetrant used be kept to the minimum necessary amount. Therefore, the use concentration of the penetrant can be preferably 1% by weight or less.

  Further, the use concentration of the wetting agent is 0.01% by weight or more, and the penetration effect on wood can be obtained, but the stable penetration effect is obtained by 0.1% by weight or more. In addition, it is desirable that the use concentration of the wetting agent is limited to the necessary minimum amount because the wetting agent remains in the wooden sheet and affects the durability of the diaphragm. Accordingly, the use concentration of the wetting agent is preferably 20% by weight or less, and more preferably 10% by weight or less for a wooden sheet having a thickness of 0.01 mm to 1 mm.

As the “sheet member made of a material different from the wooden sheet”, for example, a non-woven fabric, paper, a woven fabric, or the like can be used. When the electroacoustic transducer diaphragm according to the present invention is applied to an earphone, a headphone or the like, a film such as a soft plastic film may be used. When applied to a speaker, in addition to a soft plastic film, sponge, cardboard, glass fiber, or the like may be used. When it is necessary to reduce the thickness of the wooden sheet alone, it is preferable to select a film or paper as the “sheet member made of a material different from that of the wooden sheet”. In other cases, the other materials described above are selected. Is preferred.

  When the laminated sheet requires uniform strength in the vertical and horizontal directions, for example, a woven fabric such as a biaxial woven fabric or a four-axial woven fabric may be bonded to the wooden sheet. The woven fabric has an advantage that a diaphragm having a light weight and high rigidity can be easily obtained because it is easy to adjust a required portion or an axial strength to a required size.

  The bonded sheet is not limited to a sheet in which a nonwoven fabric or paper or woven fabric is bonded to one side of a single wooden sheet, but a sheet in which a nonwoven fabric or paper or woven fabric is bonded to both sides of a single wooden sheet. But you can.

  Moreover, the nonwoven fabric, paper, or woven fabric does not necessarily have to be applied to the entire surface of the wooden sheet, and may be applied partially. Then, the bonded nonwoven fabric or paper or fabric may be peeled off from the wooden sheet after press-heating.

  As for the thickness of the single wooden sheet, 0.01 mm to 3 mm which can be used as a wooden sheet is a preferable range, but particularly 0.01 mm to 0.1 mm for a small diaphragm for an earphone or a headphone. Is preferably in the range of 0.01 mm to 0.3 mm, which is usually easy to fabricate by wig peeling or slicing, and for large bass diaphragms from 1 mm to 2 mm or more than 2 mm 3 mm is a preferred range.

  In addition, when the bonded sheet containing the aqueous solution is formed into a predetermined shape, the temporary sheet is temporarily formed by primary press thermoforming, and then a thermosetting resin is included and formed into a predetermined shape by secondary press thermoforming. You may make it do.

  According to the present invention, in addition to the water containing the penetrating agent and the wetting agent entering the wooden sheet to give the wooden sheet elasticity, the penetrating agent and the wetting agent have an effect of giving more water to the wooden sheet. By exhibiting it, it is possible to realize a large elongation of the wooden sheet, so that it becomes difficult for the wooden sheet to break in the mold at the time of press heat forming, and the yield rate is improved. The weight ratio of water, penetrant, and wetting agent is appropriately adjusted according to the degree of stretchability and moisture absorption of the wooden sheet. Since the wooden sheet is stretched substantially uniformly in the mold during press thermoforming, a diaphragm for an electroacoustic transducer with less variation in thickness can be obtained, so that the electrical power of speakers, earphones, headphones, etc. using this can be obtained. The acoustic characteristics of the acoustic transducer are improved.

  In addition, both the penetrant and the wetting agent do not cause seizure in the press-molding mold, so that the releasability of the workpiece from the mold, the workpiece dirt, the mold stain, etc. It does not occur. Therefore, the yield rate is improved, and the work of peeling the seizure from the diaphragm or the mold is unnecessary, so that productivity is improved and manufacturing cost is reduced.

  Hereinafter, an embodiment of the present invention will be described. FIG. 1 is a flowchart showing a method of manufacturing an electroacoustic transducer diaphragm according to the present invention, and FIG. 2 is an explanatory diagram of the first embodiment.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 2A, a sheet member (nonwoven fabric) other than a wooden sheet is provided on one surface side of the wooden sheet 2 having a thickness of about 0.25 mm via an adhesive layer 3. ) 4 is prepared, and an aqueous solution containing 0.05% by weight of sodium butylnaphthalene sulfonate is prepared. As shown in FIG. 2 (b), the laminated sheet 1 is cut into an appropriate size. Then, it is immersed in this aqueous solution 5. And it is immersed until the flexibility comes out to the bonding sheet | seat 1 (about 20 minutes).

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable laminated sheet 1 is press thermoformed with a mold 6 heated to 100 ° C. or higher in advance as shown in FIG. 2 (c). To do. The mold 6 is a male and female type consisting of a male mold 7 and a female mold 8 formed in a predetermined shape, and has heaters 9 and 10.

  In addition to the butyl naphthalene sulfonic acid soda entering the wooden sheet 2 and imparting elasticity to the wooden sheet 2, the butyl naphthalene sulfonic acid soda exerts more moisture on the wooden sheet 2, thereby Since the large elongation of the sheet 2 can be realized, the wooden sheet 2 is unlikely to break in the mold 6 during press-heating.

  Further, since no lubricant is contained in the aqueous solution 5, no deposits are generated on the mold 6 during pressing, and the bonded sheet 1 is not baked on the mold 6, and there are defects such as cracks. A good molded product was obtained.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 12 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 11 as shown in FIG. . At the same time, vibration by the ultrasonic vibrator 13 is applied to the thermosetting resin solution 11 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied.

  Next, in the drying step 104 shown in FIG. 1, the molded article 12 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 14 at room temperature, as shown in FIG. 2 (e).

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 6 shown in FIG. 2C is heated in advance to 150 ° C. or higher, and secondary press thermoforming is performed on the molded product 12.

  As described above, the molded product 12 formed into the diaphragm shape in the primary press thermoforming step 102 is impregnated with a thermosetting resin, and then press thermoformed again in the secondary press thermoforming step 105. By doing so, the shape retention of the molded product 12 is improved and it becomes difficult to return to the shape before molding, so that the yield rate is improved.

  Next, in a molding step 106 shown in FIG. 1, a punching process is performed in which a center hole is formed in the molded product 12 and the molded product 12 is molded to a predetermined outer diameter using a punching die having a predetermined shape. Then, the molded product 12 is coated with a moisture resistant resin. As a result, as shown in FIG. 2 (f), a trumpet-shaped molded article 12 (speaker diaphragm) having a center hole 15 is obtained.

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 3A, a sheet member (Japanese paper) other than a wooden sheet is provided on one surface side of a wooden sheet 17 having a thickness of about 0.25 mm via an adhesive layer 18. ) 19 was prepared, and a mixed aqueous solution 20 containing 5% by weight of polyethylene glycol and 0.1% by weight of sodium di2ethylhexylsulfosuccinate was prepared as shown in FIG. 3 (b). Then, the bonded sheet 16 is cut into an appropriate size and immersed in the aqueous solution 20. Immerse the laminate sheet 16 until it becomes supple (about 20 minutes). Note that some ethyl alcohol was dissolved in the aqueous solution 20 in order to speed up the drying time of the workpiece.

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable laminated sheet 16 is press thermoformed with a mold 21 heated to 100 ° C. or higher in advance as shown in FIG. To do. The mold 21 is a male and female type comprising a male mold 22 and a female mold 23 formed in a predetermined shape, and has heaters 24 and 25. At the time of pressing, since no lubricant is contained in the aqueous solution 20, no deposits are generated on the mold 21, the bonded sheet 16 is not baked on the mold 21, and there are no defects such as cracks. A good molded product was obtained.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 26 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 27 as shown in FIG. At the same time, vibration by the ultrasonic vibrator 28a is applied to the thermosetting resin solution 27 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied. As a result of observing the molded product 26 thus provided in an atmosphere of a temperature of 60 ° C. and a relative humidity of 90% for 24 hours, it was found that the deformation was remarkably small as compared with the case where no ultrasonic wave was used.

  Next, in the drying step 104 shown in FIG. 1, the molded product 26 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 29a at room temperature, as shown in FIG. 3 (e). Compared with methods using high temperature air (for example, infrared lamps or hot air forced drying), forced drying with normal temperature wind has a defect rate of cracking of about one-tenth in the secondary press thermoforming process 105 in the next process. It turns out that it can be suppressed.

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 21 shown in FIG. 3C is heated in advance to 150 ° C. or higher, and secondary press thermoforming is performed on the molded product 26.

  As described above, the molded product 26 formed into the diaphragm shape in the primary press thermoforming process 102 is impregnated with the thermosetting resin, and then the secondary press thermoforming process 105 is performed again by press thermoforming. This improves the shape retention of the molded product 26 and makes it difficult to return to the shape before molding, thereby improving the yield rate.

  Then, in the molding step 106 shown in FIG. 1, after a punching process for forming a center hole in the molded product 26 and molding the molded product 26 to a predetermined outer diameter using a punching die having a predetermined shape, Coat the resin. As a result, as shown in FIG. 3F, a trumpet-shaped molded product 26 (speaker diaphragm) having a central hole 27a is obtained.

  Next, the 3rd Embodiment of this invention is described based on FIG.1 and FIG.4.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 4A, bonding in which a nonwoven fabric 31 is bonded to one surface side of a wooden sheet 29 having a thickness of about 0.5 mm via an adhesive layer 30. A sheet 28 is prepared, and as shown in FIG. 4B, an aqueous solution 32 containing 0.1% by weight of di2ethylhexylsulfosuccinate soda is prepared, and the laminated sheet 28 is cut into an appropriate size. Immerse in. And it is immersed in the bonding sheet | seat 28 until flexibility comes out (about 20 minutes).

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable bonded sheet 28 is press thermoformed with a die 33 that has been heated to 100 ° C. or higher in advance as shown in FIG. To do. The mold 33 is of a male and female type comprising a male mold 34 and a female mold 35 formed in a predetermined shape, and has heaters 36 and 37. At the time of pressing, since no lubricant is contained in the aqueous solution 32, no deposits are generated on the mold 33, the bonded sheet 28 is not baked on the mold 33, and there are no defects such as cracks. A good molded product was obtained.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 38 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 39 as shown in FIG. . Immerse until the thermosetting resin sufficiently penetrates the molding 38 (about 60 minutes).

  Next, in the drying step 104 shown in FIG. 1, the molded product 38 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 40 at room temperature, as shown in FIG. Compared with methods using high temperature air (for example, infrared lamps or hot air forced drying), forced drying with normal temperature wind has a defect rate of cracking of about one-tenth in the secondary press thermoforming process 105 in the next process. It turns out that it can be suppressed.

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 33 shown in FIG. 4C is heated in advance to 150 ° C. or higher, and secondary press thermoforming is performed on the molded product 38.

  As described above, the molded product 38 formed into the diaphragm shape in the primary press thermoforming step 102 is impregnated with the thermosetting resin and then subjected to the secondary press thermoforming, thereby forming the molded product 38. This improves the shape retention and makes it difficult to return to the shape before molding, thus improving the yield rate.

  In the molding step 106 shown in FIG. 1, after performing a punching process for forming the center hole 41 in the molded product 38 and molding the molded product 38 to a predetermined outer diameter using a punching die having a predetermined shape. Coat with moisture-resistant resin. As a result, as shown in FIG. 4 (f), a trumpet-shaped molded product 38 (speaker diaphragm) in which the center hole 41 is formed is obtained.

  Next, the 4th Embodiment of this invention is described based on FIG.1 and FIG.5.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 5A, a bonded sheet in which a nonwoven fabric 45 is bonded to both surfaces of a wooden sheet 43 having a thickness of about 0.25 mm via an adhesive layer 44. As shown in FIG. 5 (b), an aqueous solution 46 containing 10% by weight of ethyl alcohol and 0.05% by weight of 2-ethylhexyl sulfosuccinate soda is prepared, and the laminated sheet 42 is cut to an appropriate size. Then, it is immersed in this aqueous solution 46. And it is immersed until the flexibility comes out to the bonding sheet | seat 42 (about 20 minutes).

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable bonded sheet 42 is press thermoformed with a die 47 heated to 100 ° C. or higher in advance as shown in FIG. To do. The mold 47 is of a male and female type consisting of a male mold 48 and a female mold 49 formed in a predetermined shape, and has heaters 50 and 51. At the time of this pressing, since no lubricant is contained in the aqueous solution 46, no deposits are generated on the mold 47, and the bonded sheet 42 is not baked on the mold 47. Further, the reinforcing effect of the nonwoven fabric 45 provided on both surfaces of the bonded sheet 42 has resulted in a highly productive process with no cracking defects.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 52 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 53 as shown in FIG. . At the same time, vibration by the ultrasonic vibrator 54 is applied to the thermosetting resin solution 53 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied.

  Next, in the drying step 104 shown in FIG. 1, the molded product 52 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 55 at room temperature, as shown in FIG.

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 47 shown in FIG. 5C is heated in advance to 150 ° C. or higher, and the press molding is performed on the molded product 52.

  As described above, the molded product 52 molded in the shape of the diaphragm in the primary press thermoforming process 102 is impregnated with the thermosetting resin and then subjected to the secondary press thermoforming, thereby forming the molded product 52. This improves the shape retention and makes it difficult to return to the shape before molding, thus improving the yield rate.

  Then, in the molding step 106 shown in FIG. 1, after a punching process for forming a center hole in the molded product 52 and molding the molded product 52 to a predetermined outer diameter using a punching die having a predetermined shape, Coat the resin. As a result, as shown in FIG. 5F, a trumpet-shaped molded product 52 (speaker diaphragm) having a center hole 56 is obtained. It should be noted that by applying heat-resistant wood grain printing to the surface of the nonwoven fabric 45 on the inner surface side in advance, it is possible to meet the demands of people who prefer a wood-tone appearance.

  Next, a fifth embodiment of the present invention will be described with reference to FIGS.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 6A, a nonwoven fabric 60 is bonded in advance to one surface side of a wooden sheet 58 having a thickness of about 0.25 mm via an adhesive layer 59. A laminated sheet 57 in which a nonwoven fabric 73 is bonded to the other surface side of the sheet 58 via a spot-like adhesive layer 72 is prepared. As shown in FIG. 6B, 5% by weight of glucose and sodium laurate are added. An aqueous solution 61 containing 0.02% by weight is prepared, and the bonded sheet 57 is cut into an appropriate size and immersed in the aqueous solution 61. And it is immersed in the bonding sheet | seat 57 until flexibility comes out (about 20 minutes).

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable bonded sheet 57 is press thermoformed with a mold 62 heated to 100 ° C. or higher in advance as shown in FIG. 6C. To do. The mold 62 is of a male and female type consisting of a male mold 63 and a female mold 64 formed in a predetermined shape, and has heaters 65 and 66. At the time of this pressing, since no lubricant is contained in the aqueous solution 61, no deposit is generated on the mold 62, and the bonded sheet 57 is not baked on the mold 62. In addition, the reinforcing effect of the nonwoven fabrics 60 and 73 provided on both surfaces of the bonded sheet 57 resulted in a highly productive process with no crack defects. After press thermoforming, the nonwoven fabric 73 spot-bonded to the inner surface side is peeled off from the wooden sheet 58.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 67 formed by the primary press thermoforming step 102 and the non-woven fabric 73 is peeled off, as shown in FIG. Immerse in the resin solution 68. At the same time, vibration by the ultrasonic vibrator 69 is applied to the thermosetting resin solution 68 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied.

  Next, in the drying step 104 shown in FIG. 1, the molded product 67 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 70 at room temperature, as shown in FIG. 6 (e).

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 62 shown in FIG. 6C is heated in advance to 150 ° C. or higher, and secondary press thermoforming is performed on the molded product 67.

  As described above, the molded product 67 formed into the diaphragm shape in the primary press thermoforming step 102 is impregnated with a thermosetting resin and then subjected to secondary press thermoforming, thereby forming the molded product 67. This improves the shape retention and makes it difficult to return to the shape before molding, thus improving the yield rate.

  Then, in the molding step 106 shown in FIG. 1, after a punching process for forming a center hole in the molded product 67 and molding the molded product 67 to a predetermined outer diameter using a punching die having a predetermined shape, Coat the resin. As a result, as shown in FIG. 6F, a trumpet-shaped molded product 67 (speaker diaphragm) in which the center hole 71 is formed is obtained.

  Next, a sixth embodiment of the present invention will be described with reference to FIGS.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 7A, a four-axis woven cloth 77 is attached to one surface of a wooden sheet 75 having a thickness of about 0.25 mm via an adhesive layer 76. A combined bonded sheet 74 is prepared, and as shown in FIG. 7B, an aqueous solution 78 containing 5% by weight of glucose and 0.05% by weight of 2-ethylhexyl sulfosuccinate soda is prepared. Cut into dimensions and immersed in this aqueous solution 78. And it is immersed in the bonding sheet 74 until flexibility comes out (about 20 minutes).

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable laminated sheet 74 is press thermoformed with a die 79 that has been heated to 100 ° C. or higher in advance, as shown in FIG. 7C. To do. The mold 79 is a male and female type consisting of a male mold 80 and a female mold 81 formed in a predetermined shape, and has heaters 82 and 83. At the time of this pressing, since no lubricant is contained in the aqueous solution 78, no deposits are generated on the mold 79, and the bonded sheet 74 is not baked on the mold 79. In addition, since the four-axis woven fabric 77 provided on one side of the bonded sheet 74 provides uniform reinforcement in the vertical and horizontal directions, the process has a higher productivity without cracking defects.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 84 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 85 as shown in FIG. . At the same time, vibration by the ultrasonic vibrator 86 is applied to the thermosetting resin solution 85 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied.

  Next, in the drying step 104 shown in FIG. 1, the molded article 84 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 87 at room temperature, as shown in FIG.

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the die 79 shown in FIG. 7C is heated in advance to 150 ° C. or higher, and press molding is performed again on the molded product 84.

  In this way, the molded product 84 molded in the shape of the diaphragm in the primary press thermoforming process 102 is impregnated with a thermosetting resin and then subjected to press thermoforming again. Since the shape retention is improved and it becomes difficult to return to the shape before molding, the yield rate is improved.

  Then, in the molding step 106 shown in FIG. 1, after a punching process for forming a center hole in the molded product 84 and molding the molded product 84 to a predetermined outer diameter using a punching die having a predetermined shape, Coat the resin. As a result, as shown in FIG. 7F, a trumpet-shaped molded article 84 (speaker diaphragm) in which a center hole 88 is formed is obtained.

  Next, a seventh embodiment of the present invention will be described with reference to FIGS.

  First, in the dipping process 101 shown in FIG. 1, as shown in FIG. 2A, a sheet material other than a wooden sheet is disposed on one surface of a wooden sheet 2 having a thickness of about 0.25 mm via an adhesive layer 3. A non-woven fabric) 4 is prepared, and an aqueous solution containing 0.05% by weight of sodium butylnaphthalenesulfonate is prepared. As shown in FIG. Cut and immerse in this aqueous solution 5. And it is immersed until the flexibility comes out to the bonding sheet | seat 1 (about 20 minutes). Butyl naphthalene sulfonic acid soda is a kind of alkyl naphthalene sulfonic acid soda and is a penetrant. Further, the sheet material 4 other than the wooden sheet can serve as a reinforcing material for reinforcing the strength of the wooden sheet 2. For example, the sheet material 4 other than the wooden sheet is paper made by weaving with yarn made of paper pulp.

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable laminated sheet 1 is press thermoformed with a mold 6 heated to 100 ° C. or higher in advance as shown in FIG. 2 (c). To do. The mold 6 is a male and female type consisting of a male mold 7 and a female mold 8 formed in a predetermined shape, and has heaters 9 and 10.

  In addition to the butyl naphthalene sulfonic acid soda entering the wooden sheet 2 and imparting elasticity to the wooden sheet 2, the butyl naphthalene sulfonic acid soda exerts more moisture on the wooden sheet 2, thereby Since the large elongation of the sheet 2 can be realized, the wooden sheet 2 is unlikely to break in the mold 6 during press-heating.

  Further, since no lubricant is contained in the aqueous solution 5, no deposits are generated on the mold 6 during pressing, and the bonded sheet 1 is not baked on the mold 6, and there are defects such as cracks. A good molded product was obtained.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 12 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 11 as shown in FIG. . At the same time, vibration by the ultrasonic vibrator 13 is applied to the thermosetting resin solution 11 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied.

  Next, in the drying step 104 shown in FIG. 1, the molded article 12 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 14 at room temperature, as shown in FIG. 2 (e).

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 6 shown in FIG. 2C is heated in advance to 150 ° C. or higher, and the press-molding is performed again on the molded product 12.

  As described above, the molded product 12 formed into the diaphragm shape in the primary press thermoforming step 102 is impregnated with the thermosetting resin, and then the press thermoforming is performed again in the secondary press thermoforming step 105. By making it, the shape retention of the molded product 12 is improved and it becomes difficult to return to the shape before molding, so the yield rate is improved.

  Next, in a molding step 106 shown in FIG. 1, a punching process for molding the molded product 12 to a predetermined outer diameter is performed on the molded product 12 using a punching die having a predetermined shape. Then, the molded product 12 is coated with a moisture resistant resin. Thus, unlike FIG. 2 (f), a small diaphragm 804 for an earphone or a headphone in which the center hole 15 is not formed is formed. The obtained diaphragm 804 is shown in FIG.

  Next, the 8th Embodiment of this invention is described based on FIG.1 and FIG.3.

  First, in the dipping step 101 shown in FIG. 1, as shown in FIG. 3A, a sheet member other than a wooden sheet is provided on one surface of a wooden sheet 17 having a thickness of approximately 0.025 mm via an adhesive layer 18. 19 is prepared, and as shown in FIG. 3B, a mixed aqueous solution 20 containing 5% by weight of ethylene glycol and 0.1% by weight of sodium di2ethylhexylsulfosuccinate is prepared as shown in FIG. The bonded sheet 16 is cut to an appropriate size and immersed in the aqueous solution 20. Immerse the laminate sheet 16 until it becomes supple (about 20 minutes). Note that some ethyl alcohol was dissolved in the aqueous solution 20 in order to speed up the drying time of the workpiece. Here, ethylene glycol and ethyl alcohol are wetting agents, and di-2-ethylhexylsulfosuccinate sodium is a kind of dialkylsulfosuccinate and a penetrant. Further, the sheet member 19 other than the wooden sheet can serve as a reinforcing material for reinforcing the strength of the wooden sheet 2. For example, the sheet member 19 is a non-woven fabric or a 4-axis woven fabric.

  Next, in the primary press thermoforming step 102 shown in FIG. 1, the pliable laminated sheet 16 is press thermoformed with a mold 21 heated to 100 ° C. or higher in advance as shown in FIG. To do. The mold 21 is a male and female type comprising a male mold 22 and a female mold 23 formed in a predetermined shape, and has heaters 24 and 25. At the time of pressing, since no lubricant is contained in the aqueous solution 20, no deposits are generated on the mold 21, the bonded sheet 16 is not baked on the mold 21, and there are no defects such as cracks. A good molded product was obtained.

  Next, in the thermosetting resin impregnation step 103 shown in FIG. 1, the molded product 26 obtained in the primary press thermoforming step 102 is immersed in the thermosetting resin solution 27 as shown in FIG. At the same time, vibration by the ultrasonic vibrator 28a is applied to the thermosetting resin solution 27 and immersed until the thermosetting resin sufficiently permeates (about 5 minutes). Immersion while applying ultrasonic waves requires approximately one-tenth of the time required for the thermosetting resin to penetrate sufficiently, compared to the case where ultrasonic waves are not applied. As a result of observing the molded product 26 thus obtained in an atmosphere having a temperature of 60 ° C. and a relative humidity of 90% for 24 hours, it was found that the deformation was remarkably small as compared with the case where no ultrasonic wave was used.

  Next, in the drying step 104 shown in FIG. 1, the molded product 26 infiltrated with the thermosetting resin is forcibly dried while blowing air with a fan 29a at room temperature, as shown in FIG. 3 (e). Compared with methods using high temperature air (for example, infrared lamps or hot air forced drying), forced drying with normal temperature wind can suppress the defect rate of cracking in press-heat forming in the next process to about 1/10. all right.

  Next, in the secondary press thermoforming step 105 shown in FIG. 1, the mold 21 shown in FIG. 3C is heated in advance to 150 ° C. or higher, and press molding is performed on the molded product 26 again.

  Thus, after impregnating the molding 26 molded in the shape of the diaphragm in the primary press thermoforming step 102 with the thermosetting resin, the press thermoforming is performed again in the secondary press thermoforming step 105. By doing so, the shape retention of the molded product 26 is improved and it becomes difficult to return to the shape before molding, so the yield rate is improved.

  Then, in the molding step 106 shown in FIG. 1, after a punching process for forming a center hole in the molded product 26 and molding the molded product 26 to a predetermined outer diameter using a punching die having a predetermined shape, Coat the resin. As a result, unlike FIG. 3F, a small diaphragm 804 for an earphone or a headphone in which the center hole 27a is not formed is formed. The diaphragm 804 is shown in FIG.

(Speaker configuration)
FIG. 8 is a cross-sectional view of a speaker using the electroacoustic transducer diaphragm according to the first to sixth embodiments.
In the speaker 700, a rubber edge 702 having a predetermined shape is bonded to the outer periphery of the trumpet-shaped speaker diaphragm 701 manufactured by the manufacturing method according to any of the first to sixth embodiments, A bobbin (a predetermined damper 704 is bonded in advance) of a voice coil 703 having a predetermined shape is inserted and bonded to the center hole of the speaker diaphragm 701.

  These three integrated parts are attached to a predetermined speaker housing 705 (a predetermined magnetic circuit 706 is previously installed) by adhesion. A metal wire (not shown) for energization is drawn out from the voice coil 703 and connected to a terminal (not shown, which is insulated from the metal housing 705 in advance) attached to the housing 705. Has been.

  The magnetic circuit 706 includes a donut-shaped plate 707, a donut-shaped magnet 708, a pole 709, and the like, and a voice coil 703 is loosely inserted in a magnetic gap 710 formed between the plate 707 and the pole 709. By magnetizing the magnet 708, the speaker is completed. Reference numeral 711 denotes a dust cap that prevents foreign matter from entering the voice coil 703, and reference numeral 712 denotes an annular arrow paper that holds the end of the edge 702.

  In the speaker 700, the thickness of the speaker diaphragm 701 formed of a wooden sheet is substantially uniform, and excellent acoustic characteristics with little distortion are obtained.

  Loudspeaker diaphragms made of wooden sheets can produce reproduced sounds that are close to natural sounds. In particular, they can reproduce medium to high sounds such as human voices and violin sounds, and have a high-quality appearance. Therefore, it can be used for high-quality audio devices, high-quality home theater systems, broadcast station monitors, etc. that require high-quality sound quality and high-quality appearance.

(Earphone or headphone configuration)
FIG. 9A is a cross-sectional view illustrating an example in which the diaphragm according to the seventh and eighth embodiments is applied to an earphone or a headphone.

  In FIG. 9A, a predetermined shape is formed on the outer periphery of a dome-shaped diaphragm 804 made of a wooden sheet 802 and other sheet members 803 produced by any of the manufacturing methods shown in the seventh and eighth embodiments. A shape edge 801 is bonded around the entire circumference. The edge 801 is made of rubber or a soft plastic film.

  FIG. 9B is a cross-sectional view showing an example of a headphone using the diaphragms according to the seventh and eighth embodiments. A headphone 800 shown in FIG. 9B has a bobbin (voice coil bobbin) having a voice coil 806 having a predetermined shape bonded to the center portion of the diaphragm according to the seventh and eighth embodiments. Yes. An outer peripheral portion of the vibration plate 804 is bonded to a housing 816 constituting a part of the back air chamber 809, and the vibration plate 804 is fixed to the housing 816. When a current flows in the voice coil 806 on the permanent magnet 805 side, a mechanical driving force is generated in the voice coil 806, and the driving force is transmitted to the diaphragm 804 through the voice coil bobbin 815. Information as a change in current becomes the movement of the diaphragm 804, and the surrounding air is vibrated, resulting in a sound with information. The sound reaches the ear (not shown) through the ear canal 813. At this time, an air pad 812 is provided to prevent the sound from spreading outside the ear and to block noise from the outside, thereby improving the adhesion between the side of the face and the headphones 800. In order to make the vibration of the diaphragm 804 smoother and to control the movement of air on the rear surface of the diaphragm 804, a back air chamber 810, a rear leakage hole 807, and a back air chamber 809 are provided. Further, in order to control the movement of the entire surface of the diaphragm 804, a front polar chamber 811 is provided, and a number of front leakage holes 808 are provided in the protective material 823 and the protective material edge 822.

  When the diaphragm 804 shown in FIG. 9A is applied to an earphone, the structure shown in FIG. 9B may be modified. For example, as shown in FIG. 9C, a projection 917 to be inserted into the ear canal is provided at the center of the mounting surface.

  In the earphone 900 shown in FIG. 9C, a bobbin (voice coil bobbin) 906 of a voice coil 906 having a predetermined shape is bonded to the central portion of the diaphragm according to the seventh and eighth embodiments. An outer peripheral portion of the vibration plate 904 is bonded to a housing 916 constituting a part of the back air chamber 909, and the vibration plate 904 is fixed to the housing 916. When a current flows in the voice coil 906 on the permanent magnet 905 side, a mechanical driving force is generated in the voice coil 906, and the driving force is transmitted to the diaphragm 904 through the voice coil bobbin 916. Information as a change in current becomes a movement as vibration of the diaphragm 904, and the surrounding air is vibrated, resulting in a sound with information. Sound reaches the ear (not shown) through the ear canal 913. Further, an ear hole projection 917 is provided in front of the ear hole in front of the diaphragm 904, and a through hole through which sound passes is provided at the center. By inserting the ear hole projection 917 into the ear canal, it is possible to prevent the sound from spreading outside the ear and to prevent external noise.

  In order to make the vibration of the diaphragm 904 smoother and to control the movement of air on the rear surface of the diaphragm 904, a back air chamber 910, a rear leakage hole 907, and a back air chamber 909 are provided. Further, in order to control the movement of the entire surface of the diaphragm 904, a front polar chamber 911 is provided, and a number of front leakage holes 908 are provided in the protective material 923 and the protective edge 922.

  The speakers, headphones, and earphones are also called electroacoustic transducers. The electroacoustic transducer further includes a buzzer and the like in addition to the above embodiment.

  According to the manufacturing method of the present invention, this type of electroacoustic transducer diaphragm can be manufactured at a lower cost, so that not only the above-mentioned expensive products but also low-cost stationary audio devices and It can also be used for portable audio devices.

  Further, according to the manufacturing method of the present invention, the elasticity of the wooden sheet is improved, so that it can be processed into a complicated shape, and a highly fashionable product that requires a variety of shapes and space requirements. It can also be used for compact products that are difficult to handle.

Therefore, it can be said that the present invention is extremely useful because a great degree of satisfaction can be obtained in any product. The present invention is not limited to the above-described embodiments, and is within the scope not departing from the gist of the present invention. Various modifications can be made to each of the embodiments.

It is explanatory drawing of the manufacturing method of the diaphragm for electroacoustic transducers of this invention. It is explanatory drawing of 1st Embodiment of this invention. It is explanatory drawing of 2nd Embodiment of this invention. It is explanatory drawing of 3rd Embodiment of this invention. It is explanatory drawing of 4th Embodiment of this invention. It is explanatory drawing of 5th Embodiment of this invention. It is explanatory drawing of 6th Embodiment of this invention. It is sectional drawing of one Embodiment of the speaker apparatus using the diaphragm for electroacoustic transducers by the manufacturing method of this invention. It is sectional drawing of one Embodiment of the earphone or headphone using the diaphragm for electroacoustic transducers based on the 7th and 8th Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laminated sheet 2 ... Wooden sheet 3 ... Adhesive layer 4 ... Nonwoven fabric 5 ... Aqueous solution 6 ... Mold 7 ... Male type 8 ... Female type 9 ... Heater 11 ... Thermosetting resin solution 12 ... Molded product 13 ... Ultrasonic Vibrator 14 ... Fan 15 ... Center hole 16 ... Sheet 17 ... Wooden sheet 18 ... Adhesive layer 19 ... Sheet member other than wooden sheet 20 ... Aqueous solution 21 ... Mold 22 ... Male mold 23 ... Female mold 24 ... Heater 26 ... Molding Material 27a ... Center hole 27 ... Thermosetting resin solution 28 ... Sheet 28a ... Ultrasonic vibrator 29a ... Fan 29 ... Wooden sheet 30 ... Adhesive layer 31 ... Non-woven fabric 32 ... Aqueous solution 33 ... Mold 34 ... Male die 35 ... Female Mold 36 ... Heater 38 ... Molded product 39 ... Thermosetting resin solution 40 ... Fan 41 ... Center hole 42 ... Sheet 43 ... Wooden sheet 44 ... Adhesive layer 45 ... Non-woven fabric 46 ... Aqueous solution 47 ... Mold 48 ... Mold 49 ... Female mold 50 ... Heater 52 ... Molded product 53 ... Thermosetting resin solution 54 ... Ultrasonic vibrator 55 ... Fan 56 ... Center hole 57 ... Sheet 58 ... Wooden sheet 59 ... Adhesive layer 61 ... Aqueous solution 62 ... Gold Type 63 ... Male type 64 ... Female type 65 ... Heater 67 ... Molded product 68 ... Thermosetting resin solution 69 ... Ultrasonic vibrator 70 ... Fan 71 ... Center hole 72 ... Adhesive layer 73 ... Non-woven fabric 74 ... Sheet 75 ... Wooden Sheet 76 ... Adhesive layer 77 ... Shaft woven cloth 78 ... Aqueous solution 79 ... Mold 80 ... Male mold 81 ... Female mold 84 ... Molded product 85 ... Thermosetting resin solution 86 ... Ultrasonic vibrator 87 ... Fan 88 ... Center hole 90 ... Relative humidity 700 ... Speaker 701 ... Speaker diaphragm 702 ... Edge 703 ... Voice coil 704 ... Damper 705 ... Housing 706 ... Magnetic circuit 707 ... Plate 708 ... Mug Net 709 ... pole 710 ... magnetic gap 801 ... edge 802 ... wooden sheet 803 ... sheet member 804 ... acoustic diaphragm 805 ... permanent magnet 806 ... voice coil 807 ... rear leak hole 808 ... front leak hole 809 ... back air chamber 810 ... back polar chamber 811 ... front polar chamber 812 ... air pad 813 ... ear hole 814 ... wearing surface

Claims (4)

  A laminated sheet in which a sheet member made of a material different from that of the wooden sheet is bonded to at least one surface of a single wooden sheet, and includes an aqueous solution containing a penetrant or an aqueous solution containing a penetrant and a wetting agent. The electroacoustic transducer diaphragm, wherein the bonded sheet is formed into a predetermined shape as a diaphragm by primary press thermoforming.   A laminated sheet in which a sheet member made of a material different from the wooden sheet is bonded to at least one surface of a single wooden sheet, and includes an aqueous solution containing a penetrant or an aqueous solution containing a penetrant and a wetting agent. A thermosetting resin material is disposed in at least one of the inside and the surface of the bonded sheet temporarily formed by primary press heat molding, and is formed into a predetermined shape as a diaphragm by secondary press heat molding. A diaphragm for an electroacoustic transducer.   The electroacoustic transducer diaphragm according to claim 1 or 2, wherein the sheet member made of a material different from the wooden sheet is a non-woven fabric or paper.   The diaphragm for an electroacoustic transducer according to claim 1 or 2, wherein the sheet member made of a material different from the wooden sheet is a woven fabric.

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