JP2010034620A - Voice coil assembly and loudspeaker using the same, and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a voice coil assembly capable of achieving a flat thin loudspeaker having a high efficiency, hardly causing divided vibrations, obtaining a flat frequency response, and hardly causing operation defects. <P>SOLUTION: The voice coil assembly includes a structure in which two internal rectangular coils fixed on the inner wall surface of each of two rectangular spaces adjacent to each other with a partitioning surface as a boundary are connected so that an audio signal current can be conducted in the same direction in each of one side x1 of one internal rectangular coil v1 and one side x2 of the other internal rectangular coil v2 which follow the partitioning wall surface, wherein a thickness tb1 defining the thickness of the partitioning wall surface of a lattice-like bobbin is made thinner than a thickness tb2 defining the thickness of the other part of the internal wall surface, and is thinned to be not more than a total thickness tc0 of a thickness tc1 defining the thickness of the one side x1 of the one internal rectangular coil v1 and a thickness tc2 defining the thickness of the one side x2 of the internal rectangular coil v2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a speaker including a magnetic circuit using a plurality of magnets, a bobbin, and a voice coil assembly using a plurality of coils, and more particularly to a flat thin speaker having a thin overall height.

  In an electrodynamic speaker that converts an audio signal into audio, there is a speaker that employs a flat diaphragm as a speaker diaphragm in order to keep the total height including a magnetic circuit low. Although the overall height of the flat diaphragm is lower than that of the cone diaphragm, the rigidity tends to be insufficient to vibrate integrally without split vibration. Therefore, there is a speaker that has a plurality of voice coils in a bobbin that is fixed to a planar diaphragm, and drives the planar diaphragm with the plurality of voice coils to suppress divided vibration. Conventionally, a speaker including a flat diaphragm having a plurality of coils and a magnetic circuit using a plurality of magnets corresponding to each coil may be used as a flat thin speaker having a thin overall height.

  As a flat thin speaker having a thin overall height, there is a speaker in which a plurality of coils are arranged in a deep groove provided in a flat diaphragm having irregularities, and the coils are arranged in a magnetic gap formed between a plurality of magnets (Patent Document 1). Here, each coil is formed by separating a coil wound around a track type in a separation step, and this is loaded and bonded to a flat diaphragm. Further, there is a flat speaker that includes a bobbin formed by vacuum forming a plastic thin plate and inserts a coil into the slit of the bobbin (Patent Document 2). Since these arrange | position a coil in the place with the highest magnetic flux density called the magnetic space | gap of a magnetic circuit, the efficiency of a planar speaker can be improved. However, in a flat thin speaker with a thin overall height, when forming a bobbin in which a plurality of coils are arranged in a magnetic gap, it is necessary to make the bobbin lightweight and rigid for good sound reproduction. .

  In addition, the voice coil has a rectangular shape, and a plurality of the rectangular voice coils are joined together in the vertical and horizontal sides to form an aggregate, and the aggregate is attached to a flat plate diaphragm. There is a flat type speaker driven by (Patent Document 3). As shown in FIG. 3 of Patent Document 3, this speaker includes a plurality of magnetic circuits configured by sandwiching a magnet between the long side portions of a pair of band-shaped yokes, and the length of the other side of the band-shaped yokes of the magnetic circuit. A large number of voice coils are arranged so that one side of each voice coil is inserted between the sides. In Patent Document 3, a voice coil assembly is formed by winding a coil around a frame body so that the voice coil is formed into a square shape, and thereafter, a plurality of these are assembled by joining the vertical and horizontal sides thereof. It is described as being in the body.

  However, as long as it is shown in FIG. 2 of Patent Document 3, in this conventional voice coil assembly, each voice coil is wound around the outside of the frame corresponding to the bobbin. Even if the coils are joined to each other, adjacent bobbins constituting the voice coil assembly are separated by the thickness of the voice coil wound around the outside and cannot be brought into close contact with each other. When the bobbin has insufficient rigidity, there is a problem that the bobbin vibrates and divides, or the adjacent bobbins come into contact with each other to generate an abnormal noise. An additional weight such as an adhesive for connecting the two is required. As a result, there is a problem that the speaker diaphragm becomes heavy and the reproduction efficiency of the speaker is lowered.

  Conventionally, a voice coil in which a coil is wound on the inner diameter side of a bobbin is disclosed together with a method for reducing the number of winding steps when the coil is wound on the inner diameter side of a cylindrical bobbin (Patent Document). 4).

JP-A-60-18098 JP 63-299500 A Japanese Utility Model Publication No. 55-88590 JP-A-7-131892

  The present invention has been made in order to solve the above-described problems of the prior art. The purpose of the present invention is to provide a high frequency efficiency, a flat frequency characteristic that is difficult to generate divided vibrations, and a malfunction. An object of the present invention is to obtain a voice coil assembly capable of realizing a flat and thin speaker that does not easily occur.

  The voice coil assembly according to the present invention includes a lattice bobbin having a cross section formed in a lattice shape and having a plurality of rectangular spaces therein, and a plurality of inner walls fixed to inner walls defining the rectangular spaces of the lattice bobbins. Each of the two inner-wound rectangular coils fixed to the inner wall surfaces of the two adjacent rectangular spaces with the partition wall as a boundary, and one side of the inner-wound rectangular coil v1 along the partition surface x1 and a voice coil assembly connected so that the audio signal current is conducted in the same direction in each of the one side x2 of the inner-wound rectangular coil v2 and having a thickness that defines the thickness of the partition wall surface of the lattice bobbin The thickness tb1 is made thinner than the thickness tb2 that defines the thickness of the other part of the inner wall surface, and the thickness tc1 that defines the thickness of one side x1 of the one inner winding rectangular coil v1 and the other inner winding Rectangular coil v The thickness defining a thickness of one side x2 of tc2, is thinned thickness tc0 below the sum of.

  Preferably, in the voice coil assembly of the present invention, one side x1 and x2 of each of the two internally wound rectangular coils v1 and v2 along the partition wall surface are fixed with an adhesive without sandwiching the partition wall surface therebetween. In addition, the upper end surfaces of x1 and x2 are fixed to the lower end surface of the partition wall with an adhesive.

  More preferably, in the voice coil assembly according to the present invention, the partition surface of the lattice bobbin is extended and sandwiched between one side x1 and x2 of each of the two internally wound rectangular coils v1 and v2 along the partition surface. The partition wall extending surface is further provided, and the thickness tb0 defining the thickness of the partition wall extending surface is reduced to be equal to or less than the partition wall surface thickness tb1.

  In the voice coil assembly of the present invention, the lattice bobbins are formed of any one of polyimide, polyetherimide, a liquid crystal polymer resin material, or a metal material including aluminum or titanium.

  Preferably, the voice coil assembly of the present invention further includes a tinsel wire connected to the input end and the output end where the plurality of internal windings are connected to each other.

  Further, the speaker of the present invention includes the above voice coil assembly, a speaker diaphragm fixed to the voice coil assembly, an edge that supports the outer periphery of the speaker diaphragm so as to vibrate, an outer periphery of the edge, and a magnetic field. A plurality of magnets that are magnetized and arranged so that their magnetic poles are adjacent to each other and their magnetic poles are different from each other. And a plurality of magnets and a yoke to be fixed, and the inner rectangular coil of the voice coil assembly is disposed in a magnetic gap formed between adjacent plates and between the plates and the yoke. Yes.

  The method for manufacturing a voice coil assembly according to the present invention includes a step of forming a lattice bobbin having a partition wall surface, a step of forming a plurality of inner winding rectangular coils, and a lattice corresponding to the lattice bobbin of the bonding jig. A step of fitting a plurality of inner-wound rectangular coils in the groove-shaped groove portion, a step of applying an adhesive to the upper end surfaces of the plurality of inner-wound rectangular coils, and a lattice-shaped bobbin in the lattice-shaped groove portion of the bonding jig, Fixing a plurality of inner-wound rectangular coils to the inner wall surface defining the rectangular space of the cylindrical bobbins, bonding the upper end surfaces of the plurality of inner-wound rectangular coils and the partition wall surfaces of the lattice bobbins, and Connecting the wound voice coils to each other and connecting the tinsel wire to the input end and the output end, and removing the voice coil assembly from the lattice-shaped groove of the bonding jig after the adhesive is solidified. .

  Hereinafter, the operation of the present invention will be described.

  The voice coil assembly of the present invention is a voice coil assembly formed by closely fixing a plurality of internally wound rectangular coils to a single lattice bobbin having a lattice cross section, and the lattice bobbin has a plurality of rectangular shapes. The inner winding rectangular coil is fixed to the inner wall surface defining each rectangular space. For example, the lattice bobbin is formed of any one of polyimide, polyetherimide, a liquid crystal polymer resin material, or a metal material containing aluminum or titanium. The voice coil assembly further includes a tinsel wire connected to an input end and an output end where a plurality of internal voice coils are connected to each other, so that an audio signal current can be conducted.

  Here, the internally wound rectangular coil is a coil in a bobbin-less state in which the wound coil has a rectangular appearance corresponding to the magnetic gap shape of the magnetic circuit and does not have a bobbin as a coil winding core. The voice coils are each fixed to the inner wall surface defining the rectangular space of the lattice bobbin while being wound up. The outer dimension of the inner winding rectangular coil is substantially the same as the inner dimension of the rectangular space of the bobbin, and the inner winding rectangular coil and the rectangular space of the bobbin are fitted to each other and are closely fixed by an adhesive. . Further, in the voice coil assembly of the present invention, the two inner winding voice coils arranged with the inner wall surface sandwiched between one side of one inner winding rectangular coil and the other inner winding rectangular coil closest to the inner winding coil. On one side, the audio signal current is connected in the same direction.

  The speaker of the present invention is realized using the voice coil assembly described above. That is, the speaker of the present invention is a speaker diaphragm fixed to the voice coil assembly, an edge that supports the outer periphery of the speaker diaphragm so as to vibrate, a frame to which the outer periphery of the edge and the magnetic circuit are connected, Is provided. The magnetic circuit includes a plurality of magnets each having a rectangular flat plate crowned and magnetized so that their magnetic polarities are different from each other, and a yoke fixed to the plurality of magnets. Therefore, the internally wound rectangular coil of the voice coil assembly is disposed in the magnetic gap formed between the adjacent plates and between the plate and the yoke. In other words, two internal voice coils sandwiching the inner wall surface of the bobbin are arranged in a magnetic gap formed between adjacent plates.

  That is, of the inner wall surface of the lattice bobbin, two inner wound rectangular coils are fixedly bounded by a partition wall surface separating two rectangular spaces, and one side x1 of one inner wound rectangular coil v1 along the partition wall surface and the other In each of the sides x2 of the inner winding rectangular coil v2, the audio signal current is connected in the same direction. The thickness tb1 that defines the thickness of the partition wall surface of the lattice bobbin is made thinner than the thickness tb2 that defines the thickness of the other part of the inner wall surface. Furthermore, the thickness tb1 that defines the thickness of the partition wall surface defines the thickness tc1 that defines the thickness of one side x1 of one inner-wound rectangular coil v1, and the thickness of one side x2 of the other inner-wound rectangular coil v2. The total thickness of the thickness tc2 is made smaller than the thickness tc0. As a result, the thickness tb1 of the partition wall surface of the lattice bobbin can be made thinner than the thickness tb2 of the other portion of the inner wall surface, and the weight of the voice coil assembly including the lattice bobbin can be reduced. If the number of rectangular spaces of the lattice bobbins is increased, the number of partition walls separating them is increased. Therefore, if the thickness of each partition wall is reduced, the effect of weight reduction can be increased.

  Further, if the magnetic gap of the magnetic circuit can be made narrower, it is preferable because the magnetic flux density is improved and the efficiency of the speaker is improved. Therefore, in the voice coil assembly according to the present invention, one side x1 of each of the two inner rectangular coils v1 and v2 along the partition wall surface so that the two inner rectangular coils arranged in the same magnetic gap are closer to each other. And x2 are fixed with an adhesive without sandwiching the partition wall, and the upper end surfaces of x1 and x2 are fixed to the lower end surface of the partition surface with an adhesive. Alternatively, the voice coil assembly includes a partition wall extending surface in which the partition surface of the lattice bobbin is sandwiched and extended between one side x1 and x2 of each of the two internally wound rectangular coils v1 and v2 along the partition surface. The thickness tb0 that defines the thickness of the partition extending surface is reduced to a thickness tb1 or less. That is, the partition wall surface of the lattice bobbin is omitted between the sides x1 and x2 of the two inner-wound rectangular coils v1 and v2 along the partition wall surface, or is formed so as to be thinner than the partition wall surface. As a result, the lattice bobbins can be further reduced in weight, and even if the magnetic gap is made narrower, it is possible to realize a speaker with less gap defects and high efficiency.

  The voice coil assembly of the present invention is manufactured using an adhesive jig having a lattice groove corresponding to the lattice bobbin in the former case where the partition wall surface is not sandwiched between the two inner rectangular coils v1 and v2. It is preferable to do this. Insert a plurality of inner-wound rectangular coils into the grid-shaped groove of the bonding jig in advance, apply an adhesive to the upper end surfaces of the plurality of inner-wound rectangular coils, and insert a grid-shaped bobbin into the grid-shaped groove of the bonding jig Then, a plurality of inner winding rectangular coils are fixed to the inner wall surface defining the rectangular space of the lattice bobbin, and the upper end surfaces of the plurality of inner winding rectangular coils are bonded to the lower end surfaces of the partition walls of the lattice bobbins. To do. Then, a plurality of inner winding voice coils are connected to each other, a tinsel wire is connected to the input end and the output end, and after the adhesive is solidified, the voice coil assembly may be removed from the grid-like groove portion of the bonding jig. . Further, in the latter case having a partition extending surface formed thinner than the partition surface, a plurality of inner winding rectangular coils and a partition extending surface of a lattice bobbin are bonded, or a plurality of inner winding rectangles What is necessary is just to insert-mold a lattice bobbin by arrange | positioning a coil in a metal mold | die.

  As a result, it is possible to realize a flat and thin speaker in which a divided frequency is hardly generated and a flat frequency characteristic is obtained. In the voice coil assembly of the present invention, each inner wound rectangular coil is fixed to the inner wall surface defining the rectangular space of the bobbin, and two inner wound voice coils along the partition wall surface can be closely fixed. As a result, the rigidity of the bobbin is increased, the weight of the speaker vibration member is reduced, and the reproduction efficiency of the speaker is improved, so that stable sound reproduction can be obtained.

  The speaker equipped with the voice coil assembly of the present invention can realize a flat and thin speaker that has high efficiency, hardly generates divided vibrations, and can obtain a flat frequency characteristic, and is less likely to cause malfunction. Stable sound reproduction can be obtained.

  The voice coil assembly of the present invention has the purpose of realizing a flat and thin speaker that has high efficiency, is less likely to generate divided vibrations, has a flat frequency characteristic, and is less likely to malfunction. The two inner winding rectangular coils fixed to the inner wall surfaces of two adjacent rectangular spaces are one side x1 of one inner winding rectangular coil v1 and one side x2 of the other inner winding rectangular coil v2 along the partition wall surface. In each of the above, the voice coil assembly connected so that the audio signal current is conducted in the same direction, the thickness tb1 defining the thickness of the partition wall surface of the lattice bobbin is the thickness of the other part of the inner wall surface. And a thickness tc1 that defines the thickness of one side x1 of one inner-wound rectangular coil v1, and a thickness that defines the thickness of one side x2 of the other inner-wound rectangular coil v2. The c2, by to be thinned to a thickness tc0 following sum of realized.

  Hereinafter, a voice coil assembly according to a preferred embodiment of the present invention, a speaker using the same, and a manufacturing method thereof will be described, but the present invention is not limited to these embodiments.

  FIG. 1 is a diagram illustrating a flat and thin speaker 1 according to a preferred embodiment of the present invention. FIG. 1A is a perspective view illustrating the speaker 1 with the flat diaphragm 6 facing upward, and FIG. 1B is a cross-sectional view taken along line AA ′ illustrating the internal structure of the flat thin speaker 1. FIG. In addition, some internal structures etc. which are unnecessary for description are abbreviate | omitted.

  The flat thin speaker 1 of this embodiment is a flat thin speaker including a speaker vibrating member 5 including a substantially rectangular flat diaphragm 6, and has a length L (about 140.8 mm) that forms the diaphragm area. Compared with the speaker, the width W (about 16.2 mm) of the flat diaphragm 6 and the overall height h (about 20.0 mm) as a speaker are suppressed to be small. Specifically, a speaker magnetic circuit 2, a holding frame 3 that is fixed to the bottom surface side of the magnetic circuit 2, and a resin frame 4 that supports the periphery of the flat diaphragm 6 are further provided. The speaker magnetic circuit 2 is a magnetic circuit including 14 main magnets 22 that are magnetized so that their magnetic polarities are different from each other and arranged in a row. The frame 4 has a frame fixing portion for fixing the flat and thin speaker 1 to a cabinet (not shown) or the like.

  The speaker vibrating member 5 includes a flat diaphragm 6, an edge 7 that supports the outer peripheral end of the flat diaphragm 6 so as to vibrate, and a voice coil assembly 10 that is fixed to the back side of the flat diaphragm 6 to be described later. Prepare. For example, the flat diaphragm 6 is a molded plate of foamed resin (material: PC (polycarbonate)), and its outer peripheral portion is supported by an edge 7 containing rubber (material: foamed rubber). Is fixed to the frame 4. The voice coil assembly 10 is fixed to the back side of the flat diaphragm 6, and a plurality of inner-wound rectangular coils 9 (14 in this embodiment) attached to the voice coil assembly 10 are connected to the voice signal current. Is supplied to the voice coil assembly 10 by the magnetic circuit 2, and as a result, when the flat diaphragm 6 vibrates, the flat thin speaker 1 reproduces sound.

  As shown in FIG. 1B, the magnetic circuit 2 includes a yoke 21 made of a magnetic metal, 14 main magnets 22, a rectangular plate 23 crowned on top of these magnets 22, and a rectangular plate. And repulsive magnets 24 respectively crowned on the upper part of 23. The yoke 21 has a planar plate portion 21 a and a side wall portion 21 b (not shown) that defines a magnetic gap between the rectangular plate 23. Specifically, the yoke 21 and the rectangular plate 23 are formed by pressing an iron plate.

  Fourteen main magnets 22 are arranged in a row on the plate portion 21a of the yoke 21 so that their magnetic polarities are different from each other. Each of the 14 main magnets 22 is magnetized by selecting two sets so that the rectangular plate 23 is fixed in advance and the rectangular plate 23 side has an N pole or an S pole. Then, the 14 magnetized main magnets 22 are aligned and fixed so that the magnetic poles are different from each other by using a jig on the plate portion 21a of the yoke 21. In the magnetic gaps formed in places where the magnetic polarities are different from each other, the magnetic flux flies from the N pole toward the S pole. Therefore, in each magnetic gap provided in the magnetic circuit 2, the direction according to the arrangement of the main magnets 22. Magnetic flux flies to. In addition, the repulsive magnet 24 magnetized in advance is selected on the N or S pole so that the magnetic field lines due to the repulsive magnetic field fly from the side surface of the rectangular plate 23 and fixed to the upper surface side of the rectangular plate 23 with an adhesive. Is done. Therefore, the magnetic gap formed between the rectangular plates 23 adjacent to the magnetic circuit 2 and between the rectangular plate 23 and the side wall 21b of the yoke 21, that is, the magnetic gap provided in a lattice shape is high. Magnetic flux density distribution is obtained.

  FIG. 2 is a view for explaining the voice coil assembly 10 constituting the flat and thin speaker 1. 2A is an enlarged cross-sectional view of a part of the voice coil assembly 10, FIG. 2B is a plan view of the voice coil assembly 10, and FIG. 2C is a voice coil. 1 is a perspective view showing an entire assembly 10. FIG. 3 is an enlarged cross-sectional view of a part of the voice coil assembly 10 fixed to the back side of the flat diaphragm 6 of the flat thin speaker 1. In these drawings, a part of the configuration is shown transparently for explanation. The voice coil assembly 10 has a lattice-shaped bobbin 11 having a cross-sectional shape formed in a lattice shape and having 14 rectangular spaces 12a therein and 14 inner surfaces 12b that define the rectangular spaces 12a. An internally wound rectangular coil 9.

  The lattice bobbin 11 is formed of a resin material liquid crystal polymer with an injection mold and is formed in a lattice shape (ladder shape) with an average thickness of 0.2 mm, and 14 rectangular spaces 12a arranged in a row. Is stipulated. The inner wound rectangular coil 9 is fitted into the rectangular space 12a of the lattice bobbin 11 and is then firmly fixed to the inner wall surface 12b with an adhesive. Specifically, the internal dimension of the rectangular space 12a is about 9.1 mm × about 9.1 mm. Since the rectangular bobbin 12 is formed in a rectangular shape by the inner wall surface 12b and the partition wall surface 12d, the rectangular bobbin 12 has a rectangular space 12a inside and the outer wall surface 12c forms four planes. In the case of the lattice-shaped bobbin 11 formed of resin as in the present embodiment, a step 12e (to be described later) on which the inner winding rectangular coil 9 is locked is provided on the inner wall surface 12b that defines the rectangular space 12a. it can.

  The inner winding rectangular coil 9 is a coil wound with a copper wire having a wire diameter of 0.12 mm in a bobbinless state so that the outer dimension is a rectangular shape of about 9.1 mm × about 9.1 mm. The outer dimension of the inner winding rectangular coil 9 substantially matches the inner dimension of the rectangular space 12 a of the lattice bobbin 11. A thickness tc1 (or tc2) that defines the thickness of one side of the internally wound rectangular coil 9 is about 0.3 mm. In manufacturing the internally wound rectangular coil 9, after winding a wire around a temporary rectangular core, an adhesive or varnish is applied to the wire, and after this is cured, the core is removed and the bobbin-less inner core is removed. A wound rectangular coil 9 is formed. In addition, the rectangular bobbin 11 and the rectangular shape of the internally wound rectangular coil 9 include a case where the corners of the rectangle are curved so as to prevent the material from being bent. This curved surface may be a curved surface defined by a radius that is large enough not to contact the rectangular plate 23 or the like constituting the magnetic circuit 2.

  Therefore, in the voice coil assembly 10 of the present invention, the inner winding rectangular coil 9 of the inner winding voice coil 11 is fitted in the rectangular space 12a of the lattice bobbin 11 and then adhered to the inner wall surface 12b with an adhesive. Fixed. Further, each of the internally wound voice coils 9 in the rectangular space 12a of the lattice bobbin 11 is in the same direction on one side of one internally wound rectangular coil and one side of the other internally wound rectangular coil that is closest to this. The audio signal current is connected so as to be conducted. For example, in the voice coil assembly 10 shown in FIG. 2B, when a clockwise current I1 as shown in the figure flows through the inner wound rectangular coil 91 of the lattice bobbin 11, it is positioned on the right side thereof. The inner winding rectangular coils 91 and 92 are connected to the inner winding rectangular coil 92 so that a counterclockwise current I2 as shown flows. In other words, the inner winding rectangular coils 91 and 92 are such that the right side of the rectangle of the inner winding rectangular coil 91 located on the left side and the left side of the rectangle of the inner winding rectangular coil 92 located on the right side are in the same direction. It is connected so that the signal current is conducted.

  Here, the internally wound rectangular coils 91 and 92 are opposed to each other so as to sandwich the partition wall surface 12d constituting the inner wall surface 12b, and are connected so that the audio signal current is conducted in the same direction. Therefore, in the flat and thin speaker 1 using the voice coil assembly 10, as shown in FIG. 3, between the two rectangular plates 23 adjacent to the lattice-like magnetic gap of the magnetic circuit 2, these internally wound rectangular coils are used. 91 and 92 are arranged to face each other across the partition wall surface 12d. Since electromagnetic force acts on the inner winding rectangular coils 91 and 92 in either the upper surface direction or the lower surface direction, the voice coil assembly 10 in which other inner winding rectangular coils 9 arranged in the same manner are arranged in the magnetic gap The driving force acts in the upper surface direction or the lower surface direction, and the planar diaphragm 6 can be displaced in the upper surface direction or the lower surface direction. As a result, when the flat diaphragm 6 vibrates, the flat thin speaker 1 reproduces sound.

  That is, in the voice coil assembly 10 of the present embodiment, the plurality of internally wound rectangular coils 9 are fixed to the inner wall surfaces 12b of the nine rectangular spaces 12a. For example, as shown in FIG. 2, the two inner-wound rectangular coils 91 and 92 are divided into one side of the inner-wound rectangular coil and the one side of the inner-wound rectangular coil arranged with the partition wall surface 12d therebetween. The audio signal current is connected in the same direction. As shown in FIGS. 2 and 3, two inner-wound rectangular coils 91 and 92 are fixed to each of two adjacent rectangular spaces 12a with a partition wall surface 12d constituting the inner wall surface 12b as a boundary. . These are connected so that the audio signal currents I1 and I2 are conducted in the same direction in each of the one side x1 of one inner rectangular coil 91 and one side x2 of the other inner rectangular coil 92 along the partition wall surface 12d. Is done. Similarly, the 14 inner-wound rectangular coils 9 are connected to each other so that the directions of the driving forces acting on the voice coil assembly 10 coincide.

  In connecting the plurality of inner-wound rectangular coils 9 to each other, it does not matter whether they are connected in series or in parallel. In consideration of the impedance of each inner-wound rectangular coil 9 and the combined impedance of the whole, the connection may be made using both serial connection and parallel connection. Also, in order to make the rotation direction in which the audio signal current flows, the adjacent coils are in the reverse rotation direction, two types of coils in which the winding directions of the plurality of internally wound rectangular coils 9 are changed may be prepared. Alternatively, even if the winding directions of all the internally wound rectangular coils 9 are the same, the winding start side and the winding end side may be switched and connected to each other.

  FIG. 4 is a partially enlarged cross-sectional view for explaining the voice coil assembly 10 of the present embodiment, and is a view for explaining a cross section of the grid-like bobbin 11 that forms three rectangular spaces 12a from the end in the long axis direction. is there. Specifically, FIG. 4A is a cross-sectional perspective view of the lattice bobbin 11 taken along the center line AA ′ indicating the major axis direction of the voice coil assembly 10, and FIG. 4B is the same cross-section. It is a cross-sectional perspective view of the voice coil assembly 10 in FIG.

  As shown in FIG. 4A, the lattice bobbin 11 is a structure integrally formed of a liquid crystal polymer resin excellent in rigidity and heat resistance, and has a substantially rectangular shape constituting the inner wall surface 12b and the outer wall surface 12c. Is formed so that the thickness tb2 thereof is an average thickness of 0.3 mm. Further, the height hb2 of the outer portion is about 8.9 mm. Further, the outer portion of the lattice bobbin 11 has a step portion 12e on the inner wall surface 12b side to which the inner winding rectangular coil 9 is engaged, and the step portion 12e is formed by thinning the outer portion on the inner side. ing. In the lattice bobbin 11 shown in FIG. 4A, stepped corner portions 12f that engage with the outside of the four corners of the internally wound rectangular coil 9 are formed, but the center line A indicating the major axis direction is formed. The step portion 12f may be omitted so as to absorb part tolerance or assembly tolerance in the direction at -A '. The lattice bobbin 11 without the stepped corner portion 12f has an advantage that it is easy to mold with resin.

  The partition wall surface 12d that defines the rectangular space 12a together with the inner wall surface 12b is formed so that its thickness tb1 is an average thickness of 0.2 mm, and is thinner than the thickness tb2 of the outer shell portion. The height hb1 of the partition wall surface 12d is lower than the height hb2 of the outer portion of the lattice bobbin 11, and is formed to be about 6.1 mm. As a result, the lower end of the partition wall surface 12d matches the height of the stepped portion 12e, and the inner wound rectangular coil 9 can be locked. Therefore, the inner wound rectangular coil 9 is inserted into the rectangular space 12a of the lattice bobbin 11 from the lower side, and is engaged with and attached to the lower end portion of the partition wall surface 12d and the stepped portion 12e.

  As shown in FIG. 4B, the inner rectangular coils 91 and 92 are attached to two adjacent rectangular spaces 12a, respectively. Here, as described above, the inner-wound rectangular coils 91 and 92 are identical in one side x1 of the inner-wound rectangular coil 91 along one partition wall surface 12d and one side x2 of the other inner-wound rectangular coil 92. The audio signal current is connected in the direction to be conducted. Since the height hb1 of the partition wall surface 12d is shorter than the height hb2 of the outer portion of the grid bobbin 11, one side x1 of the internal rectangular coil 91 of the grid bobbin 11 and the internal rectangular coil 92 The one side x2 can be in close contact with each other without substantially sandwiching the partition wall surface 12d.

  That is, since the partition wall surface 12d of the lattice bobbin 11 is omitted between the sides x1 and x2 of the two inner wound rectangular coils 91 and 92 along the partition wall surface 12d, the lattice bobbin 11 Can be made lighter than before. In the lattice bobbin 11 of the present embodiment, there are 13 partition surfaces 12d separating the 14 rectangular spaces 12a. Therefore, the weight can be reduced by reducing the thickness of the partition surface 12d. When all of the lattice bobbins are formed with an average thickness of 0.3 mm (that is, the thickness of the partition wall surface 12d is not reduced to the aforementioned thickness tb1, and the height of the partition wall surface 12d is the aforementioned height hb2 In the case of this example, the weight of the lattice bobbin 11 is about 2.7 g, while the weight in the case of the comparative example is about 2.1 g. It becomes. Accordingly, the lattice bobbin 11 can be reduced in weight by about 20% or more.

  FIG. 5 is a diagram for explaining the voice coil assembly 10 and its manufacturing process. The partition surface 12d of the lattice bobbin 11 at the center line AA ′ indicating the major axis direction, the inner winding rectangular coils 91 and 92, and FIG. FIG. FIG. 5A illustrates a process of bonding the partition walls 12d of the lattice bobbins 11 and the sides x1 and x2 of the inner rectangular coils 91 and 92 using the adhesive Ad and the bonding jig Ja. FIG. 5B is a diagram for explaining the voice coil assembly 10 removed from the bonding jig Ja after the adhesive Ad is solidified. The lattice bobbins 11 having the partition wall surface 12d and the plurality of internally wound rectangular coils 9 are formed in advance in separate steps.

  The bonding jig Ja is a jig which has a predetermined lattice-shaped groove portion Jb corresponding to the shape of the lattice-shaped bobbin 11 on a base made of a material such as Duracon or fluororesin. Note that the adhesive jig Ja uses, for example, an adhesive Ad such as an epoxy adhesive or an acrylic adhesive in a process of applying using a micro-applicator, so that the adhesive Ad is applied to the lattice groove Jb. It is preferable to perform a process of coating with a fluororesin so that it can be easily removed even if it adheres and solidifies. In the case of the present embodiment, the width tj of the grid-like groove Jb shown in FIG. 5A is about 0.7 mm, and the thickness tb1 (= about) of the partition wall surface 12d of the grid-like bobbin 11 to be inserted. 0.2 mm). Further, in consideration of component tolerance or assembly tolerance in the major axis direction, a thickness tc1 (= about 0.3 mm) that defines the thickness of one side x1 of the inner winding rectangular coil 91, and one side of the inner winding rectangular coil 92 It is made larger than the total thickness tc0 (= about 0.6 mm) of the thickness tc2 (= about 0.3 mm) that defines the thickness of x2.

  Therefore, the inner winding rectangular coils 91 and 92 are fitted into the lattice-like groove Jb of the bonding jig Ja, and then the adhesive Ad is applied to the upper end surfaces of these inner winding rectangular coils 91 and 92, and then the bonding is performed. The lattice bobbin 11 is fitted into the lattice groove Jb of the jig Ja, and the inner winding rectangular coils 91 and 92 are fixed to the inner wall surface 12b defining the rectangular space 12a of the lattice bobbin 11, respectively. When the inner-wound rectangular coil 9 is fitted into the lattice-like groove Jb of the bonding jig Ja, the shape is corrected to a predetermined size and the interval between the two inner-wound rectangular coils becomes uniform. Since the outer diameter tolerance of the inner winding rectangular coil 9 is ± 0.05 mm, the distance ts between the inner winding rectangular coils 91 and 92 is 0.1 mm at the maximum. In the drawings schematically described, one side x1 of the inner-wound rectangular coil 91 and one side x2 of the inner-wound rectangular coil 92 are separated from each other. However, since the tolerance is actually very small as described above. The adhesive Ad spreads in the gap and is in close contact with the partition wall surface 12d without being sandwiched therebetween.

  Further, the adhesive Ad bonds the upper end surfaces of the inner wound rectangular coils 91 and 92 and the lower end surface of the partition wall surface 12 of the lattice bobbin 11. The adhesive Ad is preferably an epoxy-based or acrylic-based adhesive, and is applied using a micro-applicator. For example, the micro-coating machine has an extremely thin needle valve and can adjust the minimum coating amount to 0.001 cc or more, and it is predetermined with a resolution of 0.005 mm in the horizontal two-axis XY direction by a four-axis control coating robot. It is possible to apply to this part. When a trace amount coating machine uses an ultra-small amount coating nozzle made of ceramic, an appropriate amount of adhesive Ad can be applied to a predetermined portion with a minimum inner diameter of 0.005 mm. In the case of the present embodiment, the micro-coating machine is adjusted so that the coating amount is about 0.5 mg / mm, and the plurality of internally wound rectangular coils 9 are bonded to the lattice bobbins 11.

  As shown in FIG. 5, if the thickness tb1 that defines the thickness of the partition wall surface 12d of the lattice bobbin 11 is reduced to be equal to or less than the total tc0 of the thicknesses of the two sides of the inner wound rectangular coil 9, the magnetic circuit 2 One side x1 of the inner winding rectangular coil 91 and one side x2 of the inner winding rectangular coil 92 can be arranged closest to each magnetic gap provided. That is, as shown in FIG. 5B, the sides x1 and x2 of the two inner-wound rectangular coils 91 and 92 along the partition wall surface 12d are fixed with the adhesive Ad without interposing the partition wall surface 12d therebetween. The upper end surfaces of x1 and x2 are fixed to the lower end surface of the partition wall surface 12d with an adhesive Ad. Accordingly, all the internal voice coils 9 including the internal voice coils 91 and 92 are connected to each other, the tinsel wires 14 to 15 are connected to the input end and the output end, and the adhesive Ad is solidified. When the voice coil assembly 10 is removed from the lattice groove Jb of the tool Ja, the voice coil assembly 10 is completed.

  In addition, since the side x1 of the inner winding rectangular coil 91 and the side x2 of the inner winding rectangular coil 92 do not sandwich the partition wall surface 12d, the magnetic circuit 2 of the speaker 1 using the voice coil assembly 10 can be used. The magnetic gap can be made narrower. Specifically, in the case of the above comparative example, the width of the magnetic gap of the magnetic circuit 2 is about 1.4 mm or more, whereas in the case of this embodiment, it can be about 1.2 mm. The speaker 1 using the voice coil assembly 10 of the present embodiment has almost no possibility that the partition wall surface 12d of the lattice bobbin 11 contacts the two rectangular plates 23 forming the magnetic gap, and as a result, is a flat and thin speaker. Even so, it is possible to achieve a speaker with high gap efficiency and high efficiency. The lattice bobbin 11 is a structure integrally formed of a liquid crystal polymer resin excellent in rigidity and heat resistance, and since the plurality of internal winding voice coils 9 are connected to each other, the rigidity can be increased. Therefore, the voice coil assembly 10 using the lattice bobbin 11 can suppress the divided vibration of the voice coil assembly 10 and the speaker vibrating member 5 including the planar diaphragm 6.

  Further, since the shape and size of the lattice bobbin 11 can be manufactured with high accuracy, the speaker 1 capable of stable sound reproduction is realized as a result. In addition to the liquid crystal polymer, the material constituting the lattice bobbin 11 may be a resin material such as polyimide, polyetherimide, and the like. The molding method may be extrusion molding and is not limited to the above injection molding. Absent. Furthermore, the lattice-like bobbins 11 may be obtained by impact-molding a metal material containing aluminum or titanium.

  Further, the thin flat speaker 1 of the present embodiment is a case where each of the 14 main magnets 22 and the internally wound rectangular coil 9 is a common rectangular shape, but the number of magnets and coils may be two or more. Any rectangular shape may be used.

  FIG. 6 is a diagram for explaining another voice coil assembly 10 and its manufacturing process in the same manner as FIG. 5 in the previous embodiment, and shows the lattice bobbins 11 along the center line AA ′ indicating the major axis direction. It is a partially expanded sectional view of the partition surface 12d and the internally wound rectangular coils 91 and 92. FIG. 6A shows a partition surface 12d and a partition wall extending surface 12g of the grid-like bobbin 11, and inner sides x1 and x2 of the inner wound rectangular coils 91 and 92, respectively, using an adhesive Ad and an adhesive jig Ja. FIG. 6B is a diagram for explaining the voice coil assembly 10 removed from the bonding jig Ja after the adhesive Ad is solidified.

  The grid-like bobbin 11 of the present embodiment formed of a liquid crystal polymer is further provided with a partition extending surface 12g extending from the partition surface 12d. In addition, since the weight is almost the same, the common components are denoted by the same reference numerals and the description and illustration are omitted. In addition, the voice coil assembly using the grid-like bobbin of the present embodiment can constitute a flat and thin speaker 1 instead of the voice coil assembly of the previous embodiment.

  The partition wall extending surface 12g is a portion that is thinner than the partition wall surface 12d and extends from the lower end of the partition wall surface 12d, and each side x1 of the two inner rectangular coils 91 and 92 along the partition wall surface 12d. And x2. That is, the internally wound rectangular coils 91 and 92 are in a relationship of facing each other with the partition wall extending surface 12g interposed therebetween. Specifically, the thickness tb0 that defines the thickness of the partition wall extending surface 12g is about 0.1 mm, and is made thinner than the thickness tb1 (= about 0.2 mm) of the partition surface 12d. Therefore, the portion where the thickness changes between the partition wall surface 12d and the partition wall extending surface 12g defines the step portion 12e and the step corner portion 12f in the previous embodiment. The weight of the lattice bobbin 11 in the case of the present embodiment is increased by about 0.2 g compared to the case of the previous embodiment, so it is inferior in weight reduction, but is still lighter than in the case of the comparative example, With the voice coil assembly 10 using this, the speaker 1 with high efficiency can be realized.

  As shown in FIG. 6A, the lattice bobbin 11 of this embodiment is configured so that a member formed in advance with a shape having a partition wall extending surface 12g is inserted into the lattice groove Jb of the bonding jig Ja. You can do it. Further, in the step of forming the lattice bobbin 11, a plurality of internally wound rectangular coils 9 are arranged in a predetermined mold, and the lattice bobbin is insert-molded so as to have a partition wall extending surface 12g. Also good. That is, in the insert molding die, as in the case of the bonding jig Ja, the side x1 of the inner winding rectangular coil 91 and the side x2 of the inner winding rectangular coil 92 are the minimum part separation determined by part tolerance or assembly tolerance. Although separated by a distance ts, the resin injected by insert molding enters between x1 and x2 to connect the internally wound rectangular coils 91 and 92. Therefore, in the step of forming the lattice bobbin 11, a plurality of internally wound rectangular coils 9 can be fixed without using an adhesive.

  The speaker vibration member and the manufacturing method thereof according to the present invention can be applied not only to a speaker having a planar diaphragm but also to a headphone diaphragm.

It is a figure explaining the flat thin speaker by preferable embodiment of this invention. (Example 1) It is a figure explaining the voice coil assembly which comprises the flat thin speaker by preferable embodiment of this invention. (Example 1) 1 is an enlarged cross-sectional view of a part of a voice coil assembly 10 of a flat and thin speaker according to a preferred embodiment of the present invention. (Example 1) It is a figure explaining the voice coil assembly which comprises the flat thin speaker by preferable embodiment of this invention. (Example 1) It is a figure explaining the voice coil assembly by the preferable embodiment of this invention, and its manufacturing process. (Example 1) It is a figure explaining the voice coil assembly by other preferable embodiment of this invention, and its manufacturing process. (Example 2)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Speaker 2 Magnetic circuit 21 Yoke 22 Main magnet 23 Rectangular plate 24 Repulsive magnet 3 Holding frame 4 Frame 5 Speaker vibration member 6 Planar diaphragm 7 Edge 9 Inner volume rectangular coil 10 Voice coil assembly 11 Inner volume voice coil 12 Rectangular bobbin 12a Rectangular space 12b Inner wall surface 12c Outer wall surface 12d Partition wall surface 12e Step portion 12f Step corner portion 12g Partition wall extending surfaces 14, 15 Kinshi wire

Claims (7)

A lattice-shaped bobbin having a cross-sectional shape formed in a lattice shape and having a plurality of rectangular spaces therein, and a plurality of internally wound rectangular coils respectively fixed to inner wall surfaces defining the rectangular space of the lattice-shaped bobbins,
Two inner-wound rectangular coils fixed to respective inner wall surfaces of the two adjacent rectangular spaces with the partition wall as a boundary are connected to one side x1 of the inner-wound rectangular coil v1 along the partition surface and the other A voice coil assembly that is connected so that the audio signal current is conducted in the same direction in each of the sides x2 of the inner winding rectangular coil v2,
A thickness tb1 that defines the thickness of the partition wall surface of the lattice bobbin is made thinner than a thickness tb2 that defines the thickness of the other part of the inner wall surface, and one side of the one inner rectangular coil v1 The thickness tc1 that defines the thickness of x1 and the thickness tc2 that defines the thickness of one side x2 of the other inner-wound rectangular coil v2 are reduced to a total thickness tc0 or less.
Voice coil assembly. One side x1 and x2 of each of the two inner-wound rectangular coils v1 and v2 along the partition surface are fixed with an adhesive without sandwiching the partition surface, and above the x1 and x2 The end face is fixed to the lower end face of the partition wall with an adhesive,
The voice coil assembly according to claim 1. The partition wall surface of the lattice bobbin further includes a partition wall extending surface extending between one side x1 and x2 of each of the two inner-wound rectangular coils v1 and v2 along the partition surface; A thickness tb0 defining the thickness of the partition wall extending surface is reduced to be equal to or less than the thickness tb1 of the partition surface;
The voice coil assembly according to claim 1. The lattice bobbin is formed of any material of polyimide, polyetherimide, resin material of liquid crystal polymer, or metal material including aluminum or titanium.
The voice coil assembly according to any one of claims 1 to 3. A tinsel wire connected to the input end and the output end connected to each other of the plurality of inner winding voice coils;
The voice coil assembly according to any one of claims 1 to 4. The voice coil assembly according to any one of claims 1 to 5, a speaker diaphragm fixed to the voice coil assembly, an edge that supports an outer peripheral end of the speaker diaphragm so as to vibrate, A speaker comprising an outer peripheral end and a frame to which a magnetic circuit is connected,
The magnetic circuit includes a plurality of magnets each having a rectangular flat plate and magnetized so that their magnetic polarities are different from each other, and a yoke fixed to the plurality of magnets. Prepared,
The inner winding rectangular coil of the voice coil assembly is arranged in a magnetic gap formed between the adjacent plates and between the plate and the yoke.
speaker. A method of manufacturing a voice coil assembly according to any one of claims 1 to 5,
Forming the lattice bobbins having the partition walls;
Forming the plurality of internally wound rectangular coils;
Inserting the plurality of inner-wound rectangular coils into a lattice-shaped groove corresponding to the lattice-shaped bobbin of the bonding jig;
Applying an adhesive to the upper end surfaces of the plurality of internally wound rectangular coils;
The lattice bobbins are fitted into the lattice grooves of the bonding jig, and the plurality of internally wound rectangular coils are fixed to the inner wall surface defining the rectangular space of the lattice bobbins, respectively. Bonding the upper end surface of the inner wound rectangular coil and the partition wall surface of the lattice bobbin;
Connecting the plurality of inner winding voice coils to each other, and connecting a tinsel wire to the input end and the output end;
Removing the voice coil assembly from the lattice groove of the bonding jig after the adhesive is solidified;
A method for manufacturing a voice coil assembly.