JP2012249030A - Electrodynamic speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrodynamic speaker which uses a tabular coil having a winding shaft direction orthogonal to a vibration direction of a speaker diaphragm, has an oblong shape, is excellent in a sound reproduction capability, especially in a high sound area, and is suitable for being mounted on an apparatus such as a display.SOLUTION: An electrodynamic speaker includes: a first diaphragm having an approximate cone shape for emanating an acoustic wave; a second diaphragm which is arranged in front of the first diaphragm and whose outer peripheral side serves as a free end; a voice coil which has a tabular coil wound in a multi-layer state without shifting a rectangular wire relative to a winding shaft, which is arranged such that a direction of the winding shaft of the coil is orthogonal to vibration directions of the first diaphragm and the second diaphragm, and in which an inner peripheral side of the first diaphragm and an inner peripheral side of the second diaphragm are connected to each other while separating away from each other; and a magnetic circuit having a linear magnetic air gap in which the voice coil is placed.

Description

  The present invention relates to an elongated electrodynamic speaker having a shorter minor axis direction than a major axis direction, and relates to an electrodynamic speaker excellent in sound reproduction capability and suitable for mounting on a device such as a display.

  In an audio device such as a display to which a speaker for reproducing sound is attached, it is desired to reduce the space required for attaching the speaker. In particular, an electrodynamic loudspeaker intended to be slender may be limited in slenderness depending on the configuration of the magnetic circuit. In addition, slender (rectangular, oval (including elliptical, track-shaped)) electrodynamic speakers employ a speaker magnetic circuit with a high magnetic flux density in the magnetic gap, where the diaphragm area is limited in the minor axis direction. When trying to do so, there is a disadvantage in the sound reproduction capability for various reasons such as the magnetic circuit is wider than the speaker diaphragm and cannot be downsized. Therefore, in order to solve these problems, various magnetic circuits for speakers and electrodynamic speakers using the same have been proposed.

  Conventionally, in order to reduce the thickness of an electrodynamic speaker, there is a speaker provided with a plate-like driving force transmission member on which a voice coil is formed. For example, a frame, a magnetic circuit fixed to the frame, a diaphragm fixed to the frame so as to vibrate in a predetermined direction, a driving force transmission member coupled to the diaphragm, and the driving force A damper that supports the transmission member, wherein the magnetic circuit is disposed between a first plane and a second plane, and the first plane is a plane parallel to the diaphragm. The second plane is defined as a plane that is parallel to the diaphragm and that is in contact with at least a part of the magnetic circuit. The driving force transmission member has a region where a voice coil is formed, and the driving force transmission member is generated by the action of a current flowing through the voice coil and a magnetic flux provided by the magnetic circuit. The driving force in a predetermined direction is transmitted to the diaphragm, and one end of the damper is coupled to the driving force transmission member at a position between the first plane and the second plane. And the other end of the damper is coupled to the frame at a position between the first plane and the second plane. (Patent Document 1).

  In addition, as a speaker including a plate-like driving force transmission member on which a voice coil is formed, for example, a plane vibration plate is attached to the back surface of the plane vibration plate along the vibration direction so that the plane is flat. There is a flat drive speaker comprising a drive plate on which a coil is formed and a magnet that applies a magnetic field to the coil of the drive plate, and the drive plate is a printed wiring board on which a coil is printed. (Patent Document 2).

  In addition, even if a plate-like driving force transmission member is not provided, a voice coil formed of a flat coil having two linear sides facing each other at the center of a rectangular or oval diaphragm A square dynamic formed by joining one linear side surface to a diaphragm so as to be substantially perpendicular to the plate, and arranging a magnetic circuit so that the magnetic flux interlinking with the voice coil is perpendicular to the coil plane. There is a speaker (Patent Document 3). Alternatively, a diaphragm that is supported so as to vibrate in a predetermined direction, a pair of magnets arranged opposite to each other in a direction orthogonal to the vibration direction of the diaphragm, and a direction parallel to each other of the pair of magnets A voice coil wound around the direction of the winding axis, and the voice coil is joined to the diaphragm at a portion where current flows in one direction perpendicular to the winding axis direction and the vibration direction. There is a speaker device in which a portion flowing in the other direction is arranged to face the pair of magnets (Patent Document 4).

Japanese Patent No. 3891481 (FIGS. 1 to 11) Japanese Utility Model Publication No. 58-48194 (FIGS. 1 to 3) Japanese Utility Model Publication No. 59-189398 (FIGS. 1 to 3) JP 2007-129665 A (FIGS. 1 to 9)

  However, it includes an elongated electrodynamic speaker having a shorter minor axis direction than the major axis direction, and includes a flat coil disposed so that the direction of the coil winding axis is orthogonal to the vibration direction of the speaker diaphragm. In this case, for example, when a plate-like driving force transmission member as in Patent Document 1 is provided, the weight of the speaker vibration system is increased, the magnetic flux density in the linear magnetic gap is reduced, and the sound is reduced. Problems such as a reduction in the reproduction efficiency of the speaker for reproducing the image may occur. On the other hand, for example, when the plate-like driving force transmission member as in Patent Document 4 is not provided, the driving force acting on the portion of the flat coil disposed in the magnetic gap of the magnetic circuit is affected by the rigidity of the flat coil. Due to the shortage, it is not sufficiently transmitted to the speaker diaphragm joined to the flat coil, the high frequency limit frequency is lowered and a sufficient sound reproduction band cannot be secured, and as a result, an electrodynamic speaker inferior in sound reproduction ability There is a problem of becoming.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide an electrokinetic motor using a flat coil having a winding direction perpendicular to the vibration direction of the speaker diaphragm. As for the type speaker, it is an elongated type electrodynamic speaker whose short axis direction is shorter than the long axis direction, and has an excellent sound reproduction ability especially in the high sound range and is suitable for mounting on devices such as displays. There is to do.

  The electrodynamic speaker of the present invention includes a first cone-shaped diaphragm that emits sound waves, and a second cone-shaped diaphragm that is disposed on the front side of the first diaphragm and has an outer peripheral side as a free end. And a flat coil that is wound in multiple layers without shifting the flat wire with respect to the winding axis, and the direction of the winding axis of the coil is arranged to be orthogonal to the vibration direction of the first diaphragm and the second diaphragm. And the voice coil which the inner peripheral side of a 1st diaphragm and the inner peripheral side of a 2nd diaphragm connect separately, and a magnetic circuit which has a linear magnetic space | gap by which a voice coil is arrange | positioned are provided.

  Preferably, in the electrodynamic speaker of the present invention, the first diaphragm includes an engagement hole portion through which the voice coil is engaged, and the second diaphragm is engaged with which the voice coil is engaged. Has a recess.

  Preferably, in the electrodynamic speaker according to the present invention, the voice coil includes a first straight part, a second straight part formed in parallel with the first straight part, a first straight part, and a second straight part. An engagement hole portion of the first diaphragm and an engagement recess portion of the second diaphragm are respectively formed on the voice coil. The second linear portion of the voice coil is disposed in the linear magnetic gap of the magnetic circuit.

  Preferably, in the electrodynamic speaker according to the present invention, the voice coil includes a first straight part, a second straight part formed in parallel with the first straight part, a first straight part, and a second straight part. And an engagement recess of the second diaphragm is connected to the first linear portion of the voice coil to form a first vibration. The engagement holes of the plate are respectively connected to a set of connecting parts of the voice coil, and the second straight part of the voice coil is arranged in the linear magnetic gap of the magnetic circuit.

  More preferably, in the electrodynamic speaker according to the present invention, the voice coil includes a first straight portion, a second straight portion formed in parallel to the first straight portion, and the first straight portion and the second straight portion. And a pair of connecting portions that are connected to the inner peripheral space defined by the inner peripheral end portion, and the outer peripheral end portion is the inner peripheral end. A reinforcing plate that engages with the first vibration plate, the engaging recess of the second diaphragm is connected to the first linear portion of the voice coil, and the engaging hole portion of the first diaphragm is connected to the reinforcing plate of the voice coil The second straight portion of the voice coil is disposed in the linear magnetic gap of the magnetic circuit.

  The electrodynamic speaker of the present invention includes a frame connected to the magnetic circuit, an outer peripheral part connected to the frame, an inner peripheral part connected to the outer peripheral side of the first diaphragm, and an outer peripheral part and an inner peripheral part. And an edge having a support movable part defined therebetween.

  Preferably, the electrodynamic speaker of the present invention further includes a damper having an inner peripheral portion connected to the voice coil and an outer peripheral portion connected to a frame or a magnetic circuit.

  The operation of the present invention will be described below.

  The electrodynamic speaker of the present invention includes a first cone-shaped diaphragm that emits sound waves, and a second cone-shaped diaphragm that is disposed on the front side of the first diaphragm and has an outer peripheral side as a free end. And comprising. The electrodynamic speaker of the present invention includes a flat air core coil in which a flat wire is wound in multiple layers without shifting the rectangular wire with respect to the winding axis, and the direction of the winding axis of the coil is the first diaphragm and the second. A voice coil that is arranged so as to be orthogonal to the vibration direction of the diaphragm and that is connected to the inner peripheral side of the first diaphragm and the inner peripheral side of the second diaphragm, and a linear shape in which the voice coil is disposed An electrodynamic speaker comprising a magnetic circuit having a magnetic gap. That is, the electrodynamic speaker according to the present invention includes the first diaphragm for reproducing the middle / low range and the second diaphragm that is a TW cone for reproducing the high range disposed on the front surface of the first diaphragm. This is an electrodynamic speaker having a speaker diaphragm and using a flat coil having a winding direction perpendicular to the vibration direction.

  The first diaphragm is a substantially cone-shaped diaphragm, and includes an engagement hole portion through which a voice coil penetrates and engages at a central portion thereof. Further, the second diaphragm, which is a TW cone, is a substantially cone-shaped diaphragm having an outer dimension smaller than that of the first diaphragm, and has an engaging concave portion with which the voice coil is engaged at the center thereof. The voice coil includes a first straight portion, a second straight portion formed in parallel with the first straight portion, and a set of connecting portions that connect the first straight portion and the second straight portion in a ring shape. It is formed into either a track shape or a rectangular shape. Since the engagement hole portion of the first diaphragm and the engagement recess portion of the second diaphragm are separately connected to the first linear portion of the voice coil, the first diaphragm, which is a large diaphragm, is The second diaphragm, which is excellent in low-frequency reproduction and is a TW cone, constitutes a speaker vibration system that is excellent in high-frequency reproduction by directly transmitting the vibration of the voice coil.

  Further, since the second linear portion of the voice coil is disposed in the linear magnetic gap of the magnetic circuit, when an audio signal current is supplied to the voice coil, a driving force acts on the second linear portion of the voice coil. Then, the diaphragm structure including the TW cone is vibrated. Therefore, if the direction in which the linear portion of the voice coil extends is the major axis direction, and the direction parallel to the winding axis direction of the voice coil is the minor axis direction, the minor axis direction is larger than the major axis direction suitable for mounting on a device such as a display. A short and slender electrodynamic speaker can be realized. The electrodynamic speaker of the present invention includes a frame connected to the magnetic circuit, and an edge that supports the outer peripheral end of the first diaphragm by fixing the outer peripheral end to the frame. A damper is provided with a peripheral portion connected to the voice coil and an outer peripheral portion connected to a frame or a magnetic circuit.

  Of course, the engaging recess of the second diaphragm is connected to the first linear part of the voice coil, while the engaging hole of the first diaphragm is connected to a set of connecting parts of the voice coil. Good. In addition, the voice coil includes a first straight portion, a second straight portion formed in parallel with the first straight portion, and a set of connecting portions that connect the first straight portion and the second straight portion in a ring shape. And a reinforcing plate that is formed in either a track shape or a rectangular shape that is contained in an inner peripheral space defined by the inner peripheral end portion thereof, and the outer peripheral end portion engages with the inner peripheral end portion. May be. By providing this reinforcing plate, the rigidity of the speaker vibration system including the voice coil can be increased, and the driving force acting on the portion of the magnetic circuit of the voice coil that is disposed in the magnetic gap is connected to the voice coil. Fully transmit the driving force to As a result, the electrodynamic speaker using this voice coil can secure a wide audio reproduction band by increasing the high frequency limit frequency. The reinforcing plate may be made of resin or non-magnetic metal and accommodated in the inner space, and the speaker vibration system can be reduced in weight and the magnetic gap can be narrowed. The magnetic flux density in the air gap is increased, and the regeneration efficiency can be further improved.

  In addition, the 2nd diaphragm should just be a diaphragm with a small external dimension and a lighter weight than a 1st diaphragm. Specifically, the first diaphragm is a speaker diaphragm in which a base is formed by impregnating a base material including a woven or nonwoven fabric made of fibers with a thermosetting resin containing an unsaturated polyester resin, or a paper A speaker diaphragm in which a substrate based on a paper material formed by making fibers is formed, and preferably a silk fiber made of any of plain weave, twill (oblique), satin (weaver), or A surface material including a woven fabric of polyethylene naphthalate fiber may be further provided on the front side. Similarly to the first diaphragm, the second diaphragm is a speaker diaphragm in which a base material is formed by impregnating a base material including a woven or nonwoven fabric made of fibers with a thermosetting resin containing an unsaturated polyester resin. Any speaker diaphragm may be used. Preferably, the speaker vibration plate may be formed by forming a base made of a paper material obtained by making a paper fiber and forming it.

  The electrodynamic speaker using a flat coil having a winding direction perpendicular to the vibration direction of the speaker diaphragm, and in particular, a track shape formed by multilayer winding without shifting a rectangular wire with respect to the winding direction. This is a slender electrodynamic speaker that has a short-axis direction compared to the long-axis direction and is excellent in sound reproduction capability especially in the high sound range, and is suitable for mounting on devices such as displays, In addition, an electrodynamic speaker can be provided.

1 is a perspective view illustrating an electrodynamic speaker 1 according to a preferred embodiment of the present invention. Example 1 It is a partially expanded sectional view explaining the structure of the electrodynamic speaker 1 by preferable embodiment of this invention. Example 1 It is a partially expanded sectional view explaining the structure of the electrodynamic speaker 1 by preferable embodiment of this invention. Example 1 It is a figure explaining the structure of the 1st diaphragm 21, the 2nd diaphragm 22, and the voice coil 4 by preferable embodiment of this invention. Example 1 It is a figure explaining the voice coil 4 by preferable embodiment of this invention. Example 1

  Hereinafter, although the electrodynamic speaker by preferable embodiment of this invention is demonstrated, this invention is not limited to these embodiment.

1, 2 and 3 are diagrams illustrating an electrodynamic speaker 1 according to a preferred embodiment of the present invention. Specifically, FIG. 1 is a perspective view of the electrodynamic speaker 1 viewed from the front side, and FIGS. 2 and 3 are partially enlarged views of the cross section of the electrodynamic speaker 1 in the minor axis direction. . FIG. 4 is a diagram for explaining the configuration of the first diaphragm 21, the second diaphragm 22, and the voice coil 4, respectively, and shows only a half that is elongated in the major axis direction. Specifically, FIG. 4A is a front view, FIG. 4B is a side view in the major axis direction, and FIG. 4C is a sectional view in the minor axis direction. FIG. 5 is a diagram illustrating the voice coil 4 according to a preferred embodiment of the present invention. 5A is a side view of the voice coil 4 viewed from the minor axis direction, FIG. 5B is a cross-sectional view taken along the line CC ′ of the voice coil 4, and FIG. FIG. 5D is a development view illustrating the configuration of the voice coil 4. As will be described later, a part of the structure of the electrodynamic speaker 1, the internal structure, and the like are omitted. The direction in which the straight line (long axis) connecting the points A-O-A ′ extends is the major axis direction,
The direction in which the straight line (minor axis) connecting the two extends is the minor axis direction.

  The electrodynamic speaker 1 of the present embodiment is an elongated electrodynamic speaker having a track-shaped speaker diaphragm 2 having a major axis direction length L1 of about 135.6 mm and a minor axis direction length L2 of about 10.0 mm. The speaker has a diaphragm area equivalent to a circular diaphragm having an aperture of about 35 mm even if it is an elongated shape. The speaker diaphragm 2 includes a substantially corn-shaped first diaphragm 21 whose outer peripheral end is supported by an edge 3 and a second diaphragm 22 which is a TW cone (sub-cone). The outer peripheral end of the edge 3 that supports the first diaphragm 21 is fixed to the frame 6. The second diaphragm 22 disposed on the front surface side of the substantially cone-shaped first diaphragm 21 that radiates sound waves has a free end on the outer peripheral side thereof.

  In addition, a coil 4 is connected to the central portion of the speaker diaphragm 2 from the back side, and the coil 4 is supported so as to be able to vibrate by a damper 5 whose outer peripheral side is fixed to a frame 6. The coil 4 of this embodiment is a track-type coil, and is a flat coil having a winding axis direction in a direction substantially orthogonal to the vibration direction in which the speaker diaphragm 2 vibrates. Further, the frame 6 has an elongated shape corresponding to the track-shaped speaker diaphragm 2, and the magnetic circuit 10 fixed so as to be accommodated in the frame 6 also has an elongated shape having a narrow width of the minor axis direction length L2 or less. Have. Therefore, the electrodynamic speaker 1 is a speaker suitable for a device with a small width for mounting the speaker, such as a side surface of a display unit included in a device such as a display. A terminal 7 (not shown) to which an audio signal current is supplied is attached to the back side of the frame 6 and a part of the magnetic circuit 10 is exposed.

  The speaker diaphragm 2 of the electrodynamic loudspeaker 1 includes a first diaphragm 21 for middle and low frequency range reproduction, and a second diaphragm 22 that is a TW cone for high frequency range reproduction arranged in front of the first diaphragm 21. And. As shown in the figure, the first diaphragm 21 is an elongated, generally cone-shaped diaphragm disposed on the front side that emits sound waves, and the inner peripheral side of the edge 3 is bonded to the outer peripheral end thereof so that the first diaphragm 21 can vibrate. It is supported. Moreover, the 2nd diaphragm 22 is arrange | positioned at the front side of the 1st diaphragm 21, as shown in figure, has an area smaller than the 1st diaphragm 21, and the outer peripheral side is made into the free end. It is a diaphragm having a substantially cone shape. One linear portion 4b of a track-shaped coil 4 to be described later is adhered to the central back side of the second diaphragm 22 with an adhesive. Further, since the inner peripheral side of the first diaphragm 21 is also separated from the inner peripheral side of the second diaphragm 22 and is bonded to the track-shaped coil 4 with an adhesive, the speaker diaphragm 2 is shown in FIG. A speaker vibration system having a cross section in the minor axis direction illustrated in FIG. 3 is configured.

  The first diaphragm 21 constituting the speaker diaphragm 2 is formed by forming a foamed thermoplastic resin in order to reduce the weight. In the case of the present embodiment, the first diaphragm 21 having irregularities is formed by using the extruded thermoplastic resin foam sheet (specifically, polystyrene paper) by using a vacuum forming method in combination with plug assist molding. Have gained. In other words, the first diaphragm 21 constituting the elongated electrodynamic speaker 1 in which the major axis direction length L1 and the minor axis direction length L2 are remarkably different from each other tends to be noticeable due to the split vibration in the major axis direction. The cross-sectional shape is a cone shape including a substantially U shape, and the shape has rigidity in the major axis direction. The first diaphragm 21 defines a diaphragm surface having a cone shape in cross section, and a convex ridge line part on the front side or the back side, and the voice coil 4 penetrates and engages a part of the ridge line part. And a rib including an engaging hole. That is, this rib is a rib formed in the major axis direction of the second diaphragm 22, and forms an engagement hole portion that engages with the voice coil 4 on the central back surface side, and has a convex shape on the back surface side. Define the ridgeline.

  The second diaphragm 22 that constitutes the speaker diaphragm 2 is a substantially cone-shaped diaphragm having a smaller diaphragm area and higher rigidity than the first diaphragm 21. Is a speaker diaphragm in which a base body made of a paper material obtained by making paper fiber is formed. Since the second diaphragm 22 is likely to have a significant effect of split vibration in the major axis direction, like the first diaphragm 21 having a substantially cone shape, the cone having a substantially U-shaped section in the minor axis direction. It is made into the shape which has rigidity in a major axis direction so that it may become a shape. The second diaphragm 22 is an engagement in which a convex ridge line portion is defined on the front surface side of the diaphragm surface having a cone shape in cross section, and the voice coil 4 is engaged with a part of the back surface side of the ridge line portion. And a rib that defines the recess. In other words, this rib is a rib formed in the major axis direction of the second diaphragm 22, and forms an engaging recess that engages with the voice coil 4 on the center back side, and a convex ridge line on the front side. What is necessary is just the rib which prescribes | regulates a part.

  The first diaphragm 21 is a speaker diaphragm in which a base is formed by impregnating a base material including a woven or nonwoven fabric made of fibers with a thermosetting resin containing an unsaturated polyester resin, or a paper fiber is used. It may be a speaker diaphragm formed with a base made of a paper material formed by paper making. Preferably, a surface material including a woven fabric of silk fibers or polyethylene naphthalate fibers made of any one of plain weave, twill (oblique) weave and satin (weaver) weave may be further provided on the front side. Further, the substantially corn-shaped second diaphragm 22 may be formed by forming a foamed thermoplastic resin in the same manner as the first diaphragm 21, and a base including a woven fabric or a nonwoven fabric made of fibers. Any speaker diaphragm may be used as long as the base is molded by impregnating the material with a thermosetting resin containing an unsaturated polyester resin.

  In this embodiment, the edge 3 is formed by injecting flexible foam rubber into a mold and heating and foaming. The long side of the track shape that extends linearly in the major axis direction of the speaker diaphragm 2 and the short side of the track shape that has an arc shape in the minor axis direction have a thin corrugation (or so as to freely support the speaker diaphragm 2). A free edge is formed by a roll. In the case of the present embodiment, the edge 3 is connected to the back side of the second diaphragm 22 constituting the speaker diaphragm 2 having a double diaphragm structure on the inner peripheral end side. Note that, in the short side of the track shape, the edge that is arcuate in the minor axis direction may be formed as a fixed edge that is thick and does not vibrate freely so as to fix and support the speaker diaphragm 2. .

  The coil 4 corresponds to a magnetic circuit 10 to be described later, and is a flat coil having a winding direction in a direction substantially orthogonal to a vibration direction in which the speaker diaphragm 2 vibrates, and has a major axis length of about The coil has a track shape of 36.2 mm, a minor axis length of about 8.2 mm, and a thickness of 4 t of about 0.5 mm. More specifically, the coil 4 is formed by winding a copper rectangular wire having a thickness dimension of 0.12 mm × 0.20 mm into a multilayer winding without shifting the winding axis, and the thickness (41t to 42t) is the thickness of the rectangular wire. It includes two air-core coils 41 and 42 formed in a flat plate shape having a dimension approximately equal to about 0.25 mm and a winding layer thickness of about 2.3 mm, and a reinforcing plate 43 described later. The coils 41 and 42 constituting the coil 4 of this embodiment are coils having the same number of turns. The coil 4 is formed by bonding the coil end surfaces with an adhesive (or varnish) so that the winding axes of the coils 41 and 42 coincide with each other, and the bonded coils 41 and 42 are voiced in the same direction. It is a voice coil configured to be connected in series so that a signal current flows. Since the coils 41 and 42 are wound in multiple layers without shifting the rectangular wire with respect to the winding axis, there is a problem that each of the coils 41 and 42 is easily warped and deformed. It can prevent and keep a flat plate shape.

  In the track-shaped coil 4 to which the coils 41 and 42 are bonded, one linear portion 4a, the other linear portion 4b, one arc portion 4c, and the other arc portion 4d are formed to form a track shape. An inner peripheral space 4f which is a track-shaped hole is formed on the inner peripheral side of the inner peripheral end 4e. Therefore, in the coil 4, the outer peripheral end 43e of the reinforcing plate 43 accommodated in the inner peripheral space 4f is engaged with the track-shaped inner peripheral end 4e. The reinforcing plate 43 has an outer peripheral end 43e engaged with the track-shaped inner peripheral end 4e of the coil 4 and is bonded with an adhesive. That is, the outer peripheral end 43 e of the reinforcing plate 43 engages with the inner peripheral surface of the innermost winding of the coils 41 and 42. The reinforcing plate 43 of this embodiment is an aluminum plate having a thickness 43t of about 0.4 mm, and has a track shape with a major axis length of about 31.5 mm and a minor axis length of about 3.5 mm. Since the thickness 43t of the reinforcing plate 43 is made smaller than the voice coil thickness dimension 4t defined by the thickness of the coils 41 and 42 bonded together, the reinforcing plate 43 does not protrude from the inner peripheral space 4f of the coil 4. Since the reinforcing plate 43 increases the rigidity of the coil 4, it suppresses deformation that causes the flat coil 4 to warp. The reinforcing plate 43 may be made of a nonmagnetic metal such as copper, duralumin, or an aluminum alloy, but may be made of a resin such as ABS, PI, or PET. Further, the shape of the reinforcing plate 43 is not limited to a flat plate shape as in the present embodiment.

  The damper 5 is provided with a notch portion (slit portion) in a thin resin plate, and connects the inner fixing portion connected to the coil 4, the outer fixing portion connected to the frame 6, and the inner fixing portion and the outer fixing portion. And an arm-shaped movable part. Specifically, the damper 5 is a member formed by pressing a PC resin plate having a thickness of about 0.2 mm. The inner fixing portion includes an arc portion 4c to an arc portion 4d of the coil 4 and a coil. The four reinforcing plates 43 are inserted and fixed. The damper 5 is connected to the coil 4 or the frame 6 by an adhesive. The damper 5 may be a damper formed by injection molding of a resin, or may be formed by impregnating a phenol resin with a flexible fiber woven fabric as a base material.

  The frame 6 is a resin that is injection-molded into an elongated basket shape corresponding to the shape of the speaker diaphragm 2, a substantially rectangular fixing portion that fixes the edge 3, a fixing portion that fixes the magnetic circuit 10, A connecting portion for connecting these fixing portions, a window defined between the plurality of connecting portions, and a mounting hole for attaching a terminal (not shown) are provided. Therefore, the speaker vibration system including the speaker diaphragm 2, the edge 3, the coil 4, and the damper 5 is supported so as to be able to vibrate with respect to the frame 6 and the magnetic circuit 10. The frame 6 may be a metal frame formed by press-molding a steel plate.

  The magnetic circuit 10 includes yokes 11 and 12 and two rod-like magnets 13 having a rectangular cross section that are connected to the yokes 11 and 12 to form a linear magnetic gap 14. The magnet 13 of this embodiment is a rod-like rare earth magnet and is magnetized so that each plane connected to the yoke 11 or 12 has a different magnetic pole property. Therefore, a magnetic field having a high magnetic flux density is formed in the linear magnetic gap 14. Is generated. Each member constituting the magnetic circuit 10 is fixed with an adhesive. The magnetic circuit 10 is also fixed to the fixing portion of the frame 6 with an adhesive. The magnetic circuit 10 is an elongated magnetic circuit having an outer dimension with a major axis length of about 40.0 mm and a minor axis direction length of about 6.2 mm, and is almost entirely inside the frame 6 viewed from the front. Since the size is accommodated, the electrodynamic speaker 1 can be elongated. The magnetic circuit 10 is not limited to the configuration of this embodiment as long as it forms a linear magnetic gap 14.

  In the electrodynamic loudspeaker 1 of the present embodiment, the coil 4 has a track-shaped linear portion 4a disposed in the linear magnetic gap 14 of the magnetic circuit 10, and the other linear portion 4b has a double diaphragm structure. It connects with the engagement recessed part of the center part of the 2nd diaphragm 22 which comprises the speaker diaphragm 2 of this. Further, as shown in the figure, one arc portion 4c and the other arc portion 4d of the coil 4 and the reinforcing plate 43 are arranged at the center of the first diaphragm 21 constituting the speaker diaphragm 2 having a double diaphragm structure. The engagement hole portion of the portion and the slit of the inner fixing portion of the damper 5 are connected. In the present embodiment, the two coils 41 and 42 to be bonded together constituting the coil 4 are mutually the same as the bonded portions (for example, one linear portion 4a of the coil 41 and one linear portion 4a of the coil 42). They are connected in series so that the audio signal current flows in the direction. Of course, the coils 41 and 42 may be connected in parallel. In addition, the tinsel wire (not shown) connected to the coil 4 is electrically connected to the coil 4 by soldering a terminal (not shown) fixed to the frame 6 and a lead wire of the coil 4 from the terminal. Supply current. However, the tinsel wire may be electrically connected to the terminal by providing a metal eyelet on the speaker diaphragm 2.

  When an audio signal current is supplied to the coil 4 in the electrodynamic speaker 1, a driving force acts on one linear portion 4 a of the coil 4 disposed in the linear magnetic gap 14 of the magnetic circuit 10. The coil 4 includes the reinforcing plate 43 that is engaged between the one linear portion 4a and the other linear portion 4b, thereby reinforcing the coils 41 and 42 and increasing the rigidity. The reinforcing plate 43 is made of resin or non-magnetic metal and can be realized with a minimum volume accommodated in the inner circumferential space, so that the weight can be reduced, and a linear shape suitable for the thickness dimension 4t of the coil 4 can be achieved. It is not necessary to make it wider than the magnetic gap size, and a high magnetic flux density can be maintained. The reinforcing plate 43 of the present embodiment is a track-shaped flat plate that can be easily processed, but may be lightened by providing a through hole or a meat stealer. Therefore, it is possible to increase the sound reproduction efficiency and to make the electrodynamic speaker 1 having excellent sound reproduction ability. The driving force acting on the portion (one linear portion 4a of the coil 4) disposed in the magnetic gap 14 of the magnetic circuit 10 of the coil 4 is sufficiently transmitted to the speaker diaphragm 2 connected to the other linear portion 4b of the coil 4. Is done. As a result, the electrodynamic speaker 1 using this coil 4 can secure a wide audio reproduction band by increasing the high frequency limit frequency.

  As described above, the first diaphragm 21 is a substantially cone-shaped diaphragm, and includes an engagement hole portion with which the coil 4 is engaged at the center thereof. Further, the second diaphragm 22 which is a TW cone is a substantially cone-shaped diaphragm having an outer dimension smaller than that of the first diaphragm 21, and has an engagement concave portion with which the coil 4 is engaged at the center thereof. . The coil 4 has a track shape including one linear portion 4a disposed in the magnetic gap 14 of the magnetic turn 10, the other linear portion 4b, and an arc portion 4c and the other arc portion 4d that connect them. Alternatively, it is formed in a rectangular shape. As a result, the engagement hole portion of the first diaphragm 21 is connected to the arc portions 4 c and 4 d of the coil 4 and the reinforcing plate 43, and the engagement recess portion of the second diaphragm 22 is the other straight line of the coil 4. Since the first diaphragm 21 which is a large diaphragm is excellent in reproduction of the middle and low range, and the second diaphragm 22 which is a TW cone is directly transmitted to the vibration of the coil 4, the first diaphragm 21 which is a large diaphragm is connected to the portion 4b. It is possible to construct a speaker vibration system that excels in the performance.

  In the speaker diaphragm 2 of the embodiment, the first diaphragm 21, the second diaphragm 22, and the coil 4 realize a diaphragm structure that is a strong structure, and the coil 4 includes a reinforcing plate 43. Therefore, the configuration of the vibration system including the speaker diaphragm 2 is stabilized. As a result, even if the electrodynamic speaker 1 of this embodiment is an elongated electrodynamic speaker in which the vibration system operation is likely to be unstable, the coil 4 is in contact with the magnetic gap 14 of the magnetic circuit 10. It is possible to suppress problems that cause abnormal noise and cause malfunction.

  Note that the first diaphragm 21 constituting the speaker diaphragm 2 may be connected to the other linear portion 4 b of the coil 4 at the center of the engagement hole. That is, the engagement hole portion of the first diaphragm 22 and the engagement recess portion of the second diaphragm 22 may be separately connected to the linear portion 4 b of the coil 4. If the engagement hole portion of the first diaphragm 21 is connected to the other linear portion 4b of the coil 4 to which the engagement recess of the center portion of the second diaphragm 22 is connected so as to be separated from the engagement recess. Since the vibration of the coil 4 is directly transmitted to the second diaphragm 22 which is a TW cone, a speaker vibration system excellent in high-frequency range reproduction can be configured.

  In addition, the first diaphragm 21 may have a central engaging hole connected to one of the arc 4 c and the other arc 4 d of the coil 4 and the reinforcing plate 43. If the engagement hole of the first diaphragm 21 is connected to the coil 4 so as to be separated from the engagement recess at the center of the second diaphragm 22 as in the previous case, the second is a TW cone. By directly transmitting the vibration of the coil 4 to the diaphragm 22, it is possible to configure a speaker vibration system that excels in high-frequency reproduction.

  Moreover, in the coil 4 of an Example, the reinforcement board 43 is formed in the track shape corresponding to the track shape of the inner peripheral edge part 4e of a coil. However, the reinforcing plate 43 may have a rectangular shape that connects one linear portion 4a of the track shape and the other linear portion 4b. The reinforcing plate 43 may have another shape corresponding to the shape of the inner peripheral end portion of the coil. For example, when the coil is rectangular, the reinforcing plate that further improves the rigidity may be rectangular.

  In the electrodynamic speaker 1, the flat coil 4 is supported by the integrally formed damper 5 so as to be able to vibrate, but may be a damper 5 of another form. The damper 5 may be connected to one of the arc portion 4 c and the other arc portion 4 d of the coil 4 and the reinforcing plate 43. For example, the damper 5 may support the end of the coil 4 in the major axis direction so as to be able to vibrate by other forms of dampers 51 and 52, and the damper 5 can suppress the rolling of the coil 4. It is not necessary to prepare.

  The electrodynamic speaker of the present invention can be applied not only as a speaker built in video / audio equipment such as a display but also to a game machine having a cabinet with a built-in speaker for reproducing sound, a game machine such as a slot machine, etc. It is. In addition, the electrodynamic speaker provided with the magnetic circuit for a speaker according to the present invention has a narrow overall width and can realize a speaker system that reproduces sound in a small and thin cabinet. Suitable.

DESCRIPTION OF SYMBOLS 1,100 Electrodynamic type speaker 2 Speaker diaphragm 21 First diaphragm 22 Second diaphragm 3 Edge 4 Coil 41, 42 Coil 43 Reinforcement plate 5 Damper 6 Frame 10 Magnetic circuit 11, 12 Yoke 13 Magnet

Claims (7)

A first cone-shaped diaphragm that emits sound waves;
A substantially corn-shaped second diaphragm disposed on the front side of the first diaphragm and having an outer peripheral side as a free end;
A flat coil including a flat wire wound in multiple layers without shifting with respect to the winding axis is included, and the direction of the winding axis of the coil is orthogonal to the vibration direction of the first diaphragm and the second diaphragm. A voice coil that is disposed and that is connected with an inner peripheral side of the first diaphragm and an inner peripheral side of the second diaphragm separated from each other;
A magnetic circuit having a linear magnetic gap in which the voice coil is disposed,
Electrodynamic type speaker. The first diaphragm includes an engagement hole portion through which the voice coil is engaged,
The second diaphragm has an engagement recess with which the voice coil is engaged.
The electrodynamic speaker according to claim 1. The voice coil includes a first straight portion, a second straight portion formed in parallel with the first straight portion, and a set of connecting portions that connect the first straight portion and the second straight portion in an annular shape. , Formed into either a track shape or a rectangular shape,
The engagement hole portion of the first diaphragm and the engagement recess portion of the second diaphragm are connected to the first linear portion of the voice coil so as to be spaced apart from each other, and the second linear portion of the voice coil Is arranged in the linear magnetic gap of the magnetic circuit,
The electrodynamic speaker according to claim 2. The voice coil includes a first straight portion, a second straight portion formed in parallel with the first straight portion, and a set of connecting portions that connect the first straight portion and the second straight portion in an annular shape. , Formed into either a track shape or a rectangular shape,
The engaging recess of the second diaphragm is connected to the first linear portion of the voice coil, and the engaging hole portion of the first diaphragm is connected to the set of connecting portions of the voice coil. Coupled, and the second linear portion of the voice coil is disposed in the linear magnetic gap of the magnetic circuit,
The electrodynamic speaker according to claim 2. The voice coil includes a first straight portion, a second straight portion formed in parallel with the first straight portion, and a set of connecting portions that connect the first straight portion and the second straight portion in an annular shape. , Formed into either a track shape or a rectangular shape,
A reinforcing plate that is accommodated in the inner circumferential space defined by the inner circumferential end portion, and whose outer circumferential end portion engages with the inner circumferential end portion;
The engagement recess of the second diaphragm is connected to the first linear portion of the voice coil, the engagement hole of the first diaphragm is connected to the reinforcing plate of the voice coil, and The second linear portion of the voice coil is disposed in the linear magnetic gap of the magnetic circuit;
The electrodynamic speaker according to claim 2. A frame coupled to the magnetic circuit;
An edge having an outer peripheral portion connected to the frame, an inner peripheral portion connected to the outer peripheral side of the first diaphragm, and a support movable portion defined between the outer peripheral portion and the inner peripheral portion; Further comprising
The electrodynamic speaker according to any one of claims 1 to 5. An inner periphery connected to the voice coil, and an outer periphery further includes a damper connected to the frame or the magnetic circuit
The electrodynamic speaker according to claim 6.

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