JP2007325221A - Speaker and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a speaker which has an excellent sound quality, and enables cost reduction and component reutilization, can be manufactured and disposed with ease, and is environmentally-friendly. <P>SOLUTION: The speaker 1 is provided with a magnetic circuit 2, a voice coil 4 wounded on a bobbin 3 and positioned in a gap of the magnetic circuit 2 and vibrating backward and forward, a diaphragm 5 joined to the bobbin 3, an edge 6, a damper 7, a dust cap 8 covering a front face side of the bobbin 3, a gasket 9 and a frame 10. As vulcanized fiber is used as a material of the frame 10, disassembling and dismantlement of the speaker 1 can be done with ease. If the frame 10 is buried underground, decomposition is completed in a short term so that the environment-friendly speaker 1 can be realized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a speaker used for various kinds of audio equipment, information communication equipment, and the like.

  Speakers are widely used not only for audio devices but also for various electronic devices such as personal computers (hereinafter referred to as PCs), mobile phones, and game devices.

  Recently, various measures for reducing the environmental load when discarding various electronic devices have been studied, and it is desirable to use a material that can reduce the environmental load for the speaker.

  The speaker frames currently on the market are generally formed using a metal material or a resin material. When a metal material is used, a thin steel plate or an aluminum plate is press-formed, or a metal alloy material such as a zinc alloy or an aluminum alloy is cast. When a resin material is used, injection molding of a thermoplastic resin is performed.

  In general, a metal frame is firmly joined to a peripheral member such as a top plate by caulking or the like. For this reason, it is difficult to separate only the metal frame from the assembled state, the processing cost required for the separation work is increased, and as a result, the disposal cost is increased. Under such circumstances, speakers that use metal frames are not disposed of when they are discarded, but are disposed of in the soil as they are, which is against environmental protection. The parts were not reused.

  In addition, when the diaphragm vibrates in response to an acoustic signal, the metal frame is likely to cause self-resonance, and the self-resonant frequency appears in the audible frequency band, which significantly deteriorates the reproduced sound quality of the speaker. There's a problem.

  On the other hand, a plastic frame is easier to separate than a metal frame, but under the current Home Appliance Recycling Law, resin is not subject to recycling, so the separated frame is buried in the soil and discarded. Is common.

  However, since a resin hardly changes over time in soil or water as compared with metal, there is a problem in that it cannot be permanently decomposed and sufficient environmental protection cannot be achieved.

In order to cope with such a problem, a speaker having a frame made of paper made of pulp has been proposed (see claim 1 of Patent Document 1).
JP 2001-36988

  In paragraph 0027 of Patent Document 1, “A speaker using a fine pulp molded frame is easy to separate or disassemble. For example, by heating the entire speaker unit to the ignition point of paper, In addition, if the entire speaker is left in the water for a certain period of time, the frame will turn into a pulp solution.As such, the paper frame keeps the cost required for recycling low in terms of ease of separation and disassembly. Is possible. "

  Further, paragraph 0028 of Patent Document 1 states that, “In the case of landfill disposal, for example, when landfilling is simply carried out, a paper frame has a great advantage unlike other materials. Paper, like wood, is decomposed by soil bacteria. The action is completed in a short period of time, which means that the environmental impact is low.On the other hand, the steel frame is longer than the paper, and the resin frame takes a very long time or hardly decomposes. " Has been.

  However, in Patent Document 1, it is necessary to add a carbonization step after the pulp beating step, papermaking step, and drying step in order to compensate for the poor shearing workability due to the press, which is a drawback of the fine pulp mold. There is a problem that the number of work processes is complicated and the manufacturing cost increases.

  The present invention has been made in view of the above-mentioned problems, and its purpose is excellent in sound quality, low cost and reusable component parts, easy manufacture, and easy disposal. It is another object of the present invention to provide a speaker with a low environmental load and a manufacturing method thereof.

  According to one aspect of the present invention, a frame formed of vulcanized fiber as a material, a magnetic circuit fixed to the frame, wound around a bobbin, arranged in a gap of the magnetic circuit, and vibrates back and forth. There is provided a speaker characterized by comprising:

  According to another aspect of the present invention, a sheet made of vulcanized fiber is swelled and softened by containing moisture, and the swollen and softened sheet is pressed to be shaped into a speaker frame. There is provided a method for manufacturing a speaker, comprising: a step; and a step of punching an outer peripheral portion and a window hole portion of the sheet formed into the frame shape with a punching die to form a frame.

  According to the present invention, it is possible to realize a speaker that is excellent in sound quality, can be reduced in cost, can be reused, and can be easily manufactured, disposed of easily, and has a low environmental load. Specifically, the present invention uses a vulcanized fiber as the frame material. The vulcanized fiber can be easily separated and disassembled, and the degradation action by soil bacteria can be completed in a short time. For this reason, even if a frame made of separated and broken vulcanized fiber is buried in the soil, it has little influence on the environment.

  Moreover, by using vulcanized fiber as a frame material, distortion of sound due to self-resonance of the frame accompanying vibration of the diaphragm can be suppressed, and a speaker with excellent sound quality can be realized.

  Furthermore, when a vulcanized fiber is used as a frame material, the frame manufacturing process can be simplified. Further, the rust-proof plating process for the frame such as a metal frame is not necessary, and the frame itself has high insulation, so that a metal terminal for connecting a lead wire can be directly attached to the frame. This eliminates the need for an insulating terminal plate, enables cost reduction and reduction in size and weight by reducing the number of components, and simplifies the manufacturing process.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a cross-sectional structure of a speaker 1 according to an embodiment of the present invention. The speaker 1 in FIG. 1 is a so-called external magnet type electrodynamic speaker 1, and includes a magnetic circuit 2, a voice coil 4 wound around a bobbin 3, arranged in a gap of the magnetic circuit 2, and vibrates back and forth. A cone-shaped diaphragm (hereinafter simply referred to as a diaphragm) 5 joined to the bobbin 3, an edge 6, a damper 7, a dust cap 8 covering the front side of the bobbin 3, a gasket 9, and a frame 10 It has.

  The magnetic circuit 2 includes a magnet 11 magnetized in the front-rear direction, a top plate 12 joined to the front surface of the magnet 11, and a bottom yoke 13 joined to the bottom surface of the magnet 11.

  The voice coil wire 17 connected to the voice coil 4 is disposed along the surface of the diaphragm 5 and is connected to the lead wire 14 near the hole of the diaphragm 5. The lead wire 14 is for supplying an alternating current to the voice coil wire 17.

  The voice coil wire 17 and the lead wire 14 may be directly joined by solder, or may be joined by solder via a grommet attached to the diaphragm 5.

  2 (a) and 2 (b) are diagrams for explaining the joining of the voice coil wire 17 and the lead wire 14, and are enlarged views of the dotted line portion 20 in FIG. FIG. 2A shows a case where both are directly joined by the solder 21, and FIG. 2B shows a case where both are joined via the eyelet 22.

  In the case of FIG. 2A, the lead wire 15 is drawn out to the front side of the diaphragm 5 through the hole of the diaphragm 5 and joined with the voice coil wire 17 and the solder 21. On the other hand, in the case of FIG. 2B, the eyelet 22 is attached to the hole of the diaphragm 5, and the lead wire 14 is passed through the eyelet 22 and fixed with the voice coil wire 17 and the solder 21.

  In both cases of FIG. 2A and FIG. 2B, the voice coil wire 17 is fixed to the front surface of the diaphragm 5 with an adhesive 23.

  The diaphragm 5 of FIG. 1 has an inner peripheral portion joined to the bobbin 3 and an outer peripheral portion supported by an upper stage portion of the frame 10 via an edge 6. The damper 7 has an inner periphery joined to the bobbin 3 and an outer periphery joined to the front surface of the bottom of the frame 10. The front surface of the top plate 12 is joined to the bottom surface of the bottom portion of the frame 10 with screws 16.

  In the present embodiment, vulcanized fiber is used as the material of the frame 10. Vulcanized fiber is a chemical medium obtained by dipping a base paper made of cotton pulp or wood pulp in a zinc chloride solution, laminating it to an arbitrary thickness, and then sufficiently removing the zinc chloride solution by washing with water, followed by a drying process. It is a 100% natural cellulose natural material consisting of a dense and dense tissue.

  Note that the vulcanized fiber used in the frame 10 may be subjected to a flame retardant treatment by containing an appropriate amount of a halogen-based organic compound or the like suitable for the environment as necessary.

  FIG. 3 is a process chart for sequentially explaining the manufacturing process of the speaker 1 according to the present embodiment. Hereinafter, the manufacturing process will be described with reference to FIG. First, the dipping process shown in FIG. This process is a unique process that is necessary because vulcanized fiber is used.

  Since the vulcanized fiber has a high strength even in a sheet state and is harder than ordinary paper or fiber material, it cannot be formed into the shape of the frame 10 as it is. Then, the sheet | seat 31 of a vulcanized fiber is immersed in warm water 32, is swollen, and has a softness | flexibility. This process finally enables processing into a frame shape.

  The temperature and time of the hot water 32 to be immersed are important factors. For example, the vulcanized fiber is immersed in the hot water 32 for several hours in a state where the temperature is set to about 60 ° to 80 °. It should be noted that it is desirable to set the temperature and immersion time to optimum conditions depending on the thickness of the vulcanized fiber used.

  Instead of immersing the sheet 31 made of vulcanized fiber in the hot water 32, the sheet 31 may be softened by placing it under high-temperature steam or spraying high-temperature steam on the sheet 31.

  Next, press molding shown in FIG. Even if the vulcanized fiber is subjected to the dipping process shown in FIG. 3A, the vulcanized fiber maintains a certain strength and is not as good as the wood pulp used for the diaphragm 5. For this reason, when trying to obtain the final shape with a single molding press, wrinkles are partially formed or cracks occur. Therefore, it is desirable to employ a so-called multi-stage press that is processed into a final shape by a plurality of molding presses.

  FIG. 3B shows an example in which two molding presses are employed. The first molding press (step S2 in FIG. 3B) is a shallow press in which the upper die 33 and the lower die 34 of the press machine are arranged at positions where they are not completely in close contact and the fitting is suppressed. As a result, the vulcanized fiber is formed into a bowl shape. Thereafter, the upper mold 33 and the lower mold 34 are once returned to their original positions (step S3 in FIG. 3B), and then a final press is performed to completely adhere the upper mold 33 and the lower mold 34 (FIG. 3 ( Step S4) of b).

  The number of molding presses depends on the thickness of the vulcanized fiber, but two or more molding presses are required.

  When the press molding process is completed, the cutting process shown in FIG. In this step, the frame 10 is completed by punching the outer periphery and window hole portion of the sheet 31 formed into the shape of the frame 10 using the punching die 35.

  The frame 10 completed through the above steps can be waterproofed to make it difficult to deform with respect to humidity, depending on the usage environment. In this case, for example, waterproofing treatment is performed by applying a waterproofing agent such as polyester or lacquer to the frame 10, spraying or immersing the frame 10, impregnating the vulcanized fiber, or forming a waterproof film on the surface.

  Since the frame 10 manufactured using a vulcanized fiber is excellent in corrosion resistance, rust-proof plating applied to a metal frame is unnecessary.

  As described above, the frame 10 according to the present embodiment can be manufactured by a simple process, does not require large-scale manufacturing equipment, and uses less expensive materials. Therefore, the manufacturing cost is lower than that of a metal frame or a resin frame. Can be planned.

  Next, assembly of the frame 10 to the speaker 1 will be described. The frame 10 and the top plate 12 are joined with screws 16 as shown in FIG. In combination with the screw 16, the joint surface of the frame 10 and the top plate 12 may be bonded with a rubber adhesive. Thereby, vibration can be suppressed.

  In addition, when joining the frame 10 and the top plate 12, various joining methods other than the screws 16 may be used, but the screws 16 are excellent from the viewpoint of preventing breakage of the vulcanized fiber.

  For example, a rubber adhesive is used for joining the frame 10 to the edge 6 or the damper 7. In the case of a metal frame, metal parts cannot be directly attached to the frame 10, but since the frame 10 of this embodiment is an insulating material, the metal terminals 15 and the like can be directly attached to the frame 10. Thereby, the terminal board which consists of insulating materials can be abbreviate | omitted, and while being able to reduce component cost, size reduction and weight reduction are attained.

  Next, the characteristics of the speaker 1 according to the present embodiment will be described. FIG. 4 is a diagram showing output sound pressure frequency characteristics of the speaker 1 according to the present embodiment, and FIG. 5 is a diagram showing total harmonic distortion characteristics.

  In the speaker 1 according to the present embodiment, compared to the metal frame 10, the effective magnetic flux is increased because there is no loss of effective magnetic flux due to magnetic leakage to the frame 10, and the output sound pressure frequency characteristics are excellent. The output sound pressure level increases.

  Further, by using a vulcanized fiber as a material for the frame 10, distortion of sound due to self-resonance of the frame 10 itself is suppressed. In FIG. 5, a distortion characteristic of a speaker using a metal frame is indicated by a dotted line 30. As shown in the figure, the metal frame has more distortion due to resonance than the frame 10 of the present embodiment.

  As described above, in this embodiment, since the vulcanized fiber is used as the material of the frame 10, the separation and disassembling work at the time of disposal of the speaker 1 is facilitated. Since the process is completed, the speaker 1 with less environmental load can be realized.

  Further, by using the vulcanized fiber, distortion of sound due to self-resonance of the frame 10 due to vibration of the diaphragm 5 can be suppressed, and sound quality of the speaker 1 can be improved.

  Further, the manufacturing process of the frame 10 can be simplified as compared with the case where a metal frame is used, and in particular, the rust-proof plating process is not required, and the insulation performance of the frame 10 is high. A metal terminal can be directly attached, an insulating terminal board is not required, the cost of parts can be reduced, and the size and weight can be reduced.

  As mentioned above, although typical embodiment of this invention was described, this invention is not limited only to the structure of said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention.

For example, the magnetic circuit 2 of the present embodiment is an outer magnet type, but may be an inner magnet type. The speaker driving method is not limited to the electrodynamic type as in the present embodiment, and other methods such as an electromagnetic type, a piezoelectric type, and an electrostatic type are also applicable. The diaphragm 5 is not limited to the cone shape, and may be a dome shape or other shapes.

The figure which shows the cross-section of the speaker 1 by one Embodiment of this invention. FIGS. 2A and 2B are views for explaining the joining of the voice coil wire 17 and the lead wire 14. FIG. FIG. 3A to FIG. 3C are process diagrams for sequentially explaining the manufacturing process of the speaker 1 according to this embodiment. The figure which shows the output sound pressure frequency characteristic of the speaker 1 by this embodiment. The figure which shows the total harmonic distortion characteristic of the speaker 1 by this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Speaker 2 Magnetic circuit 3 Bobbin 4 Voice coil 5 Diaphragm 6 Edge 7 Damper 8 Dust cap 9 Gasket 10 Frame 11 Magnet 12 Top plate 13 Bottom yoke 14 Lead wire 15 Terminal 16 Screw 17 Voice coil wire 21 Solder 22 Eyelet 23 Adhesive 31 Sheet 32 Hot water 33 Upper mold 34 Lower mold

Claims (8)

A frame formed from vulcanized fiber,
A magnetic circuit fixed to the frame;
A speaker comprising: a voice coil wound around a bobbin and disposed in a gap of the magnetic circuit and vibrating in the front-rear direction.   The speaker according to claim 1, further comprising: a lead wire that supplies an alternating current to the voice coil; and a conductive terminal that is attached to the frame and is directly connected to the lead wire.   The speaker according to claim 1, wherein the frame includes a waterproofing agent that impregnates the molded vulcanized fiber or forms a film covering the surface.   The speaker according to claim 1, further comprising an adhesive member attached to a contact surface between the frame and a top plate in the magnetic circuit. A step of swelling and softening a sheet made of vulcanized fiber with moisture,
Pressing the swollen and softened sheet into a speaker frame shape; and
And a step of punching an outer peripheral portion and a window hole portion of the sheet formed into the frame shape by using a punching die to form a frame.   In the swelling and softening step, the sheet is immersed in warm water, the temperature of the warm water is set to a temperature according to the thickness of the sheet, and the time for immersion in the warm water is set according to the thickness of the sheet. The speaker manufacturing method according to claim 5, wherein the speaker is set.   In the pressing step, the pressing is performed in a state in which the upper mold and the lower mold are completely in contact with each other after the processing in which the upper mold and the lower mold used for pressing are not completely in close contact with each other. The manufacturing method of the speaker of Claim 5 or 6.   8. The method according to claim 5, further comprising a step of attaching a conductive terminal to the hole of the formed frame and directly connecting a lead wire for supplying an alternating current to the voice coil at the terminal. A method for manufacturing the speaker according to claim 1.

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