KR20110015015A - Electromagnetic converter - Google Patents

Abstract

The electromagnetic transducer 10 includes a permanent magnet 13, a lower frame 12 for fixing one magnetic pole surface of the permanent magnet 13, and an upper frame 11 having an opening 11a formed on the other magnetic pole side. And a diaphragm 15 having a magnetic coil composed of a plate 14 fixed to the other magnetic pole surface, and a voice coil pattern 15g disposed on the side surfaces 15b and 15c in the long side direction and the ceiling surface 15a. The peripheral part of the ceiling surface 15a of the diaphragm 15 is joined to the peripheral part of the opening 11a of the upper frame 11 via the upper gasket 16. Further, the flange portion 15f of the periphery of the periphery of the side 4 of the diaphragm 15 is joined to the inner circumferential surface of the upper frame 11, that is, inside the magnetic circuit via the lower gasket 18.

Description

Electronic converter {ELECTROMAGNETIC CONVERTER}

The present invention relates to an electronic converter that combines a permanent magnet and a diaphragm to perform voice reproduction from an audio signal.

As a conventional speaker having a structure in which a diaphragm and a voice coil pattern are integrated, there are, for example, a planar acoustic conversion device of Patent Document 1 and a speaker of Patent Document 2.

The planar acoustic conversion device of Patent Literature 1 forms a spiral voice coil pattern on a sheet made of polyimide of thermosetting resin or polyethylene terephthalate (PET) or liquid crystal polymer of thermoplastic resin, and is bent at both ends to have a cross section. It has a diaphragm molded in a "c" shape. The ceiling surface of the diaphragm and the frame are joined at elastic edges, and the voice coil patterns on both sides of the diaphragm are held so as to be in the magnetic flux generating portion of the magnetic circuit. For this reason, even if the amplitude of a diaphragm increases, the vertical displacement width of a voice coil pattern can be combined in a magnetic flux generation part.

However, this diaphragm has a problem in that the stiffness plate is low in rigidity because the diaphragm is bent at both end sides in the long side direction but not at both end sides in the short side direction, so that noise is likely to occur due to unnecessary resonance accompanying vibration. Moreover, since only the ceiling surface of a diaphragm can join together the support system, such as the edge which fixes a diaphragm to a frame, there also existed a problem that the piston vibration was disturbed at the time of a large amplitude, and the magnetic gap defect by rolling is liable to occur.

On the other hand, the speaker of patent document 2 forms the voice coil pattern in advance in thermosetting resin sheets, such as a polyimide sheet or the prepreg of the laminated sheet which consists of glass resin and an epoxy resin, heat-molded, and has a U-shaped cross-section. It has a dome-shaped diaphragm. The entire periphery of the diaphragm and the frame are joined at the edges, and the support plate is fixed inside the diaphragm, and the support plate is joined to the damper on the frame side. For this reason, rigidity can be improved by making a diaphragm into a dome shape, and the support structure of a diaphragm can be partially but doubled.

Japanese Patent Laid-Open No. 2008-113368 Japanese Patent Laid-Open No. 2000-102094

Since the conventional electronic converter is comprised as mentioned above, in the case of the structure of patent document 1, there existed a problem that the magnetic gap defect generate | occur | produced by the disturbance of piston vibration and the generation of a joint by low rigidity of a diaphragm as mentioned above.

On the other hand, in the case of the structure of patent document 2, the problem of the lack of rigidity of a diaphragm can be solved, but since the damper can only be provided in part, the problem of piston vibration disturbance could not be solved.

Moreover, in the case of the structure of patent document 2, since a magnetic circuit must be divided | segmented in order to fix a damper to a frame, there existed a problem that the number of components increased. In addition, when the magnetic circuits are divided and arranged, nonuniformity occurs in the magnetic flux density or the magnetic flux density decreases.

Moreover, in order to obtain the diaphragm of the three-dimensional structure of the shape of patent document 2 using a thermosetting resin sheet, what is necessary is just to harden | cure by a heat treatment after shape | molding the thermosetting resin sheet in which the voice coil pattern was formed in the three-dimensional structure, but a thermoplastic resin sheet In order to obtain the diaphragm of a three-dimensional structure by using, it is necessary to extend the thermoplastic resin sheet in which the voice coil pattern was formed by drawing by hot press, and to obtain a three-dimensional shape. At this time, since the elongation rate of the thermoplastic resin sheet and the elongation rate of the voice coil pattern formed on the sheet are different, there is a problem that the coil or sheet is broken when drawing. In addition, thermosetting resins have a problem of higher cost than thermoplastic resins.

This invention is made | formed in order to solve the above subjects, and an object of this invention is to make a piston vibrate the diaphragm with the double support structure of a small component structure, and to obtain the electronic converter which is excellent in performance.

The electronic transducer according to the present invention has a magnetic circuit comprising a permanent magnet, one magnetic pole surface of the permanent magnet, and the other magnetic pole side composed of an open frame and a plate fixed to the other magnetic pole surface, and at a position covering the plate. A diaphragm having a ceiling surface and four sides formed in the direction of the permanent magnet from the ceiling surface and positioned between the plate and the frame opening, and having a voice coil pattern formed on one side or both sides, and a periphery of the ceiling surface and the frame opening of the diaphragm. And a second support portion joined to the diaphragm to hold the diaphragm so as to be displaceable, and a second support portion joined to the side peripheral edge of the diaphragm and the frame inner circumferential surface so as to displace the diaphragm.

According to the present invention, the ceiling surface peripheral part of the diaphragm is joined to the frame opening peripheral part, and the side tip side peripheral part is joined to the frame inner peripheral surface. You can get a converter.

1 is an exploded perspective view showing the configuration of an electronic transducer according to Embodiment 1 of the present invention;
2 is a sectional view of an electronic transducer according to Embodiment 1,
3 is a cross-sectional view for explaining a method of assembling the electronic converter according to the first embodiment;
4 is a perspective view illustrating a configuration of a reinforcing structure provided in the diaphragm of the electromagnetic converter according to the first embodiment.

EMBODIMENT OF THE INVENTION Hereinafter, in order to demonstrate this invention in detail, the form for implementing this invention is demonstrated according to attached drawing.

≪ Embodiment 1 >

1 is an exploded perspective view showing the configuration of an electronic transducer 10 according to Embodiment 1 of the present invention, and a cross-sectional view thereof is shown in FIG. The electromagnetic transducer 10 shown in the drawing includes a magnetic circuit composed of an upper frame 11, a lower frame 12, a permanent magnet 13, and a plate 14, a diaphragm 15, and the diaphragm 15. Made of an upper gasket 16 and an edge 17 for holding the upper portion of the magnetic circuit, and a lower gasket 18 and a damper 19 for holding the diaphragm 15 inside the magnetic circuit. It consists of two supports. In addition, in this Embodiment 1, although top and bottom are distinguished for description, what kind of surface may actually be upper.

The lower frame 12 fixes one magnetic pole surface of the permanent magnet 13, the upper frame 11 covers the permanent magnet 13 and the lower frame 12, and the other magnetic pole of the permanent magnet 13 The opening 11a is positioned at approximately the same height as the surface. The plate 14 is adhered to the other magnetic pole surface of the permanent magnet 13. Thus, the plate 14 and the opening 11a are at approximately the same height position, and the magnetic flux density between the plate 14 and the opening 11a is increased.

As the diaphragm 15, thermoplastic resin sheets, such as PEI (polyetherimide), PEN (polyethylene naphthalate), PET, PEEK (polyether ether ketone), are used. The conductor thin plate is edged at a position corresponding to the ceiling surface 15a and the side surfaces 15b and 15c in the long side direction of one side or both sides of the thermoplastic resin sheet before the three-dimensional molding to form the voice coil pattern 15g. It is made into a three-dimensional structure by hot press molding. By hot press molding, the rigidity of the diaphragm 15 can be improved by shaping the four sides of the diaphragm 15 into four side surfaces 15b to 15e extending from the ceiling surface 15a. Further, in the illustrated example, the long sides 15b and 15c are formed in a shape extending vertically from the ceiling surface 15a, and the short sides 15d and 15e are obliquely from the ceiling surface 15a. It is formed in the shape which extends. Since the side surface 15b, 15c of the long side direction in which the voice coil pattern 15g was formed can be shape | molded without elongating a thermoplastic resin sheet at the time of hot press molding, there is no possibility of breaking by the difference of elongation rate.

Moreover, the flange part 15f is shape | molded by the front end side of side surface 15b-15e. This flange portion 15f serves as a fixed portion when the diaphragm 15 is bonded to the damper 19.

The periphery of the opening 17a of the edge 17 is joined to the periphery of the ceiling surface 15a of the diaphragm 15, and the outer periphery of the edge 17 is joined to the periphery of the opening 16a of the upper gasket 16. The upper gasket 16 is fixed to the upper surface of the upper frame 11. These upper gaskets 16 and the edges 17 serve as first supporting portions to support the diaphragm 15 so as to be displaceable up and down. In addition, the outer peripheral portion of the edge 17 may be directly joined to the upper frame 11 without using the upper gasket 16. In that case, since it is necessary to ensure a predetermined distance between the ceiling surface 15a and the plate 14 so as not to collide with the plate 14 when the diaphragm 15 is displaced up and down, for example, the upper frame 11 A part of the upper surface of the upper surface may be projected upward to adjust the height, or the outer peripheral portion of the edge 17 may be extended to the upper surface of the upper frame 11.

The periphery of the opening 19a of the damper 19 is joined to the flange portion 15f of the periphery of the periphery of the diaphragm 15, and the outer periphery of the damper 19 is joined to the periphery of the opening 18a of the lower gasket 18. The lower gasket 18 is fixed to the upper rear surface of the upper frame 11, that is, inside the magnetic circuit. These lower gaskets 18 and dampers 19 serve as second supporting portions to support the diaphragm 15 so as to be displaceable up and down. In addition, the outer peripheral portion of the damper 19 may be directly joined to the upper frame 11 without using the lower gasket 18.

Next, the operation principle of the electronic converter 10 will be described.

When a current (audio signal) is supplied to the voice coil pattern 15g from the outside, the current flowing through the voice coil pattern 15g and the magnetic flux generated between the opening 11a of the upper frame 11 and the plate 14. It is electromagnetically coupled and generates a driving force in accordance with Fleming's law. Due to the generated driving force, the diaphragm 15 vibrates in the vertical direction and generates sound waves. Since the entire circumference of the ceiling surface 15a of the diaphragm 15 and the entire circumference of the flange portion 15f are supported by the first and second support portions so as to be able to be displaced vertically, piston vibrations that move up and down in parallel even at a large amplitude are prevented. There is no disturbance. Therefore, the magnetic gap defect by rolling does not arise. In addition, since the diaphragm 15 does not collide with the permanent magnet 13 and the plate 14, no striking sound is generated.

Next, the assembly method of the electronic transducer 10 is demonstrated. 3 is a cross-sectional view illustrating an assembly method of the electronic transducer 10 according to the first embodiment.

As shown in FIG. 3A, the diaphragm assembly 15 is assembled by first joining the diaphragm 15, the lower gasket 18, and the damper 19. Subsequently, an adhesive 20 is applied to the upper rear surface of the upper frame 11, and the diaphragm assembly and the upper frame 11 are bonded to each other by using the outer circumference of the lower gasket 18 as a guide. The diaphragm assembly which adhere | attached the upper frame 11 is attached to the jig 21, and is fixed to a position as shown in FIG.3 (b).

Next, as shown in Fig. 3B, the upper gasket 16 and the edge 17 are joined to assemble the edge assembly. The adhesive 22 is applied to the upper surface of the upper frame 11 while the adhesive 22 is applied around the opening of the edge 17 to bond the edge assembly and the diaphragm assembly.

Subsequently, as shown in FIG. 3C, the magnet assembly is assembled by bonding the lower frame 12, the permanent magnet 13, and the plate 14, and the upper frame 11 and the lower frame 12 are assembled. Is bonded with a screw or an adhesive or the like to complete the assembly of the electronic transducer 10.

As mentioned above, according to Embodiment 1, the electromagnetic transducer 10 has the permanent magnet 13, the lower frame 12 which fixes one magnetic pole surface of this permanent magnet 13, and the opening 11a in the other magnetic pole side. ) From a magnetic circuit comprising an upper frame 11 formed with a plate and a plate 14 fixed to the other magnetic pole surface, a ceiling surface 15a at a position covering the plate 14, and the ceiling surface 15a. A diaphragm formed in the direction of the permanent magnet 13 and having four side surfaces 15b to 15e positioned between the plate 14 and the opening 11a of the upper frame 11, and having a voice coil pattern 15g ( 15), the upper gasket 16 adhered to the periphery of the opening 11a of the upper frame 11, the periphery of the ceiling surface 15a of the diaphragm 15 and the periphery of the opening 16a of the upper gasket 16. Of the edge 17 for holding the diaphragm 15 so as to be displaceable, the lower gasket 18 bonded to the inner circumferential surface of the upper frame 11, and the diaphragm 15. LAN portion is joined to the opening peripheral edge (18a) of (15f) and the lower gasket 18 were configured to include a damper 19 for holding the displaceable diaphragm (15).

For this reason, the diaphragm 15 can be supported by the double support structure of a small component structure, and piston vibration can be prevented, and generation | occurrence | production of a joint can be prevented. In addition, there is no need to divide the magnetic circuit as in the prior art, so that the number of parts increases and the cost does not increase. In addition, since there is no need to arrange the magnetic circuit separately, there is no occurrence of nonuniformity of magnetic flux density or deterioration of magnetic flux density.

Moreover, according to Embodiment 1, the diaphragm 15 has four side surfaces 15b-15e formed by hot-press molding the both side ends of the long side direction, and the both side ends of the short side direction of a thermoplastic resin sheet, and a voice coil pattern It was set as the structure arrange | positioned at the side surface 15b, 15c of the long side direction, and the ceiling surface 15a. For this reason, a low-cost thermoplastic resin can be used instead of an expensive thermosetting resin, and as a result, an inexpensive electron converter 10 can be obtained.

In addition, a reinforcing structure 15h for increasing the rigidity of the diaphragm 15 may be formed on the ceiling surface 15a of the diaphragm 15. 4 is a perspective view showing the configuration of a reinforcing structure 15h provided in the diaphragm 15 according to the first embodiment. This reinforcing structure 15h may be realized by a rib structure or uneven structure, and the direction of forming the ribs or unevenness may be a long side direction or a short side direction of the diaphragm 15 shown in FIG. 4. By providing the reinforcing structure 15h on the ceiling surface 15a, the rigidity of the diaphragm 15 can be improved more, and the performance of the electromagnetic transducer 10 can be improved.

In addition, although the method of forming the voice coil pattern 15g by edging was demonstrated in the said Embodiment 1 before hot press molding the diaphragm 15, it is not limited to this, Voice on the diaphragm 15 before three-dimensional shaping | molding is demonstrated. The coil pattern 15g may be printed and formed, or the voice coil pattern 15g may be formed by attaching a coil to the diaphragm 15 after three-dimensional molding.

Industrial availability

Since the electronic converter according to the present invention can prevent the occurrence of noise, an increase in the number of parts, and a decrease in the magnetic flux density, the electronic converter is suitable for use in an electronic converter for performing voice reproduction from an audio signal by combining a permanent magnet and a diaphragm. .

Claims (3)

A magnetic circuit comprising a permanent magnet, one magnetic pole surface of the permanent magnet, and the other magnetic pole side comprising an open frame and a plate fixed to the other magnetic pole surface;
A vibration plate having a ceiling surface in a position covering the plate and four sides formed in the direction of the permanent magnet from the ceiling surface and positioned between the plate and the frame opening, and having a voice coil pattern formed on one or both surfaces thereof;
A first support part joined to a ceiling surface peripheral part of the diaphragm and the frame opening peripheral part to hold the diaphragm so as to be displaceable;
And a second support portion joined to the lateral tip side peripheral portion of the diaphragm and the frame inner circumferential surface so as to displaceably hold the diaphragm.
Electronic converter. The method of claim 1,
The diaphragm has four side surfaces formed by hot press molding both side ends in the long side direction and both side ends in the short side direction of the thermoplastic resin sheet, and a voice coil pattern is disposed on both side surfaces and the ceiling surface in the long side direction.
Electronic converter. The method of claim 1,
The diaphragm has a rib structure or an uneven structure for reinforcement on the ceiling surface.
Electronic converter.

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