Loudspeaker

Abstract

A loudspeaker 10 includes a first vibration part 20, a second vibration part 30, a magnetic circuit 40, and a frame 50. The magnetic circuit 40 includes a first magnetic circuit 40A having a first magnetic gap G1, and a second magnetic circuit 40B having a second magnetic gap G2. The frame 50 includes: a first frame 50A to which the first vibration part 20 and the first magnetic circuit 40A are attached; and a second frame 50B to which the second vibration part 30 and the second magnetic circuit 40B are attached.

Description

Speaker

[0001] The present disclosure relates to a speaker.

[0002] The speaker disclosed in Patent Document 1 includes a second vibrating portion in addition to a first vibrating portion for emitting sound.

[0003] International Publication No. 2023 / 090124

[0004] An object of the present disclosure is to provide a speaker that includes a first vibrating portion and a second vibrating portion, and that is manufactured with consideration given to the manufacturing process.

[0005] A speaker according to a first aspect is a speaker comprising a first vibration part, a second vibration part, a magnetic circuit, and a frame supporting the first vibration part, the second vibration part, and the magnetic circuit, wherein the first vibration part comprises a first coil, a first bobbin on which the first coil is provided, and a first elastic support part that elastically supports the first bobbin so as to be displaceable in the axial direction, the second vibration part comprises a second coil having a diameter larger than that of the first coil, a second bobbin on which the second coil is provided, and a second elastic support part that elastically supports the second bobbin so as to be displaceable in the axial direction, the magnetic circuit comprises a first magnetic circuit having a first magnetic gap in which the first coil is disposed, and a second magnetic circuit having a second magnetic gap in which the second coil is disposed, and the frame comprises a first frame to which the first vibration part and the first magnetic circuit are attached, and a second frame to which the second vibration part and the second magnetic circuit are attached.

[0006] In this aspect, the speaker includes a first vibration section, a second vibration section, a magnetic circuit, and a frame. The frame supports the first vibration section, the second vibration section, and the magnetic circuit. The first vibration section includes a first coil, a first bobbin on which the first coil is provided, and a first elastic support section that elastically supports the first bobbin so as to allow axial displacement. The second vibration section includes a second coil having a larger diameter than the first coil, a second bobbin on which the second coil is provided, and a second elastic support section that elastically supports the second bobbin so as to allow axial displacement.

[0007] In this embodiment, the magnetic circuit includes a first magnetic circuit having a first magnetic gap in which the first coil is disposed, and a second magnetic circuit having a second magnetic gap in which the second coil is disposed. The frame includes a first frame to which the first vibration part and the first magnetic circuit are attached, and a second frame to which the second vibration part and the second magnetic circuit are attached. Therefore, the speaker can be manufactured by separately assembling a component (first component) including the first vibration part, the first magnetic circuit, and the first frame and a component (second component) including the second vibration part, the second magnetic circuit, and the second frame, and then combining the two components. This results in a speaker that takes the manufacturing process into consideration.

[0008] In the embodiments described below, the first vibrating portion is a vibrating portion for emitting sound, and the second vibrating portion is a vibrating portion for canceling out vibration of the entire speaker caused by the first vibrating portion. However, the first vibrating portion and the second vibrating portion in this aspect are not limited to these vibrating portions. For example, both the first vibrating portion and the second vibrating portion may be vibrating portions for emitting sound. Alternatively, the second vibrating portion may be a vibrating portion for emitting sound, and the first vibrating portion may be a vibrating portion for canceling out vibration of the entire speaker caused by the second vibrating portion. In the embodiments described below, both the first magnetic gap and the second magnetic gap are open to the upper side, which is one axial side. However, this aspect is not limited to this. In the embodiments described below, the frame includes a connecting frame that connects the first frame and the second frame. However, this aspect is not limited to this, and the frame may not include a connecting frame, and the first frame and the second frame may be directly connected.

[0009] A speaker according to a second aspect is the speaker according to the first aspect, wherein the second magnetic circuit comprises an inner magnetic member having an inner forming surface of the second magnetic gap, the inner magnetic member comprising a cylindrical wall portion having the inner forming surface of the second magnetic gap, and a bottom wall portion located radially inward from the cylindrical wall portion, the first magnetic circuit being arranged above the bottom wall portion, and the bottom wall portion being located below the upper end of the cylindrical wall portion.

[0010] In this embodiment, the second magnetic circuit includes an inner magnetic member having an inner surface defining the second magnetic gap. The inner magnetic member includes a cylindrical wall portion having the inner surface defining the second magnetic gap and a bottom wall portion located radially inward from the cylindrical wall portion. The first magnetic circuit is disposed above the bottom wall portion. Here, the bottom wall portion is located below the upper end of the cylindrical wall portion. Therefore, the magnetic circuit can be made smaller in the axial direction compared to an embodiment in which the bottom wall portion above which the first magnetic circuit is disposed is not located below the upper end of the cylindrical wall portion.

[0011] A speaker according to a third aspect is the speaker according to the first or second aspect, wherein the first frame comprises a first mounting portion to which the first elastic support portion is attached, a magnetic circuit mounting portion to which the first magnetic circuit is attached, and a connection portion that connects the first mounting portion and the magnetic circuit mounting portion, and an air vent is formed in the connection portion.

[0012] In this aspect, the first frame includes a first mounting portion to which the first elastic support portion is attached, a magnetic circuit mounting portion to which the first magnetic circuit is attached, and a connecting portion connecting the first mounting portion and the magnetic circuit mounting portion. Here, a vent hole is formed in the connecting portion. This allows the space below the first elastic support portion within the first frame to communicate with the space within the second frame. As a result, the influence of back pressure received when the second vibrating portion vibrates can be reduced, thereby suppressing the generation of abnormal noise such as wind noise. This also reduces distortion of acoustic characteristics.

[0013] A speaker according to a fourth aspect is the speaker according to any one of the first to third aspects, wherein the frame includes a connecting frame that connects the first frame and the second frame.

[0014] In this embodiment, the frame includes a connecting frame that connects the first frame and the second frame, which increases the degree of freedom in the frame structure compared to an embodiment in which the first frame and the second frame are directly connected.

[0015] A speaker according to a fifth aspect is any one of the first to fourth aspects, wherein the second elastic support portion comprises an upper elastic body, a lower elastic body provided below the upper elastic body, and a second coupler that connects the second bobbin and the upper elastic body and also connects the second bobbin and the lower elastic body.

[0016] In this aspect, the second elastic support portion includes an upper elastic body and a lower elastic body, which allows the second vibrating portion to vibrate in a stable position.

[0017] However, when the second elastic support portion includes an upper elastic body and a lower elastic body, and the upper elastic body and the lower elastic body are each joined to the second bobbin, it is necessary to elongate the portion of the second bobbin that is located outside the magnetic circuit in the axial direction. This results in an increase in the axial size of the second vibrating portion, thereby increasing the size of the entire speaker. Therefore, in this aspect, the second vibrating portion further includes a second coupler that connects the second bobbin and the upper elastic body and also connects the second bobbin and the lower elastic body. Therefore, the upper elastic body and the lower elastic body are connected to the second bobbin via the second coupler. Therefore, it is not necessary to elongate the portion of the second bobbin that is located outside the magnetic circuit in the axial direction, thereby enabling the speaker to be made smaller in size in the axial direction.

[0018] A sixth aspect of the present invention relates to the speaker of the fifth aspect, wherein at least a portion of the lower elastic body is located below an upper end of the second coil.

[0019] In this aspect, at least a portion of the lower elastic body is located below the upper end of the second coil, so that the space radially outward of the magnetic circuit and below the upper end of the second magnetic gap can be effectively used as a space for arranging the lower elastic body.

[0020] In the embodiment described below, the entire lower elastic body is located below the upper end of the second coil. However, this aspect is not limited to this. For example, the inner joint portion and the outer joint portion of the lower elastic body may be located below the upper end of the second coil, and the lower elastic body may have a portion that is not located below the upper end of the second coil.

[0021] A seventh aspect of the present invention is a speaker according to the fifth or sixth aspect, wherein an air hole is formed in the second coupler between a connection position of the upper elastic body and a connection position of the lower elastic body.

[0022] In this aspect, the second coupler has an air vent between the connection position of the upper elastic body and the connection position of the lower elastic body, which reduces the effect of back pressure that the second vibrating part receives when vibrating.

[0023] According to the present disclosure, it is possible to provide a speaker that includes a first vibrating portion and a second vibrating portion, and that takes into consideration the manufacturing process.

[0024] Fig. 5 is a cross-sectional view of a speaker according to an embodiment; Fig. 6 is an enlarged cross-sectional view of a speaker according to an embodiment; Fig. 7 is a cross-sectional view of a magnetic circuit according to an embodiment; Fig. 8 is a cross-sectional view showing a state during manufacturing of a speaker according to an embodiment; Fig. 9 is a cross-sectional perspective view of a speaker according to another embodiment (a cross-section different from that of Fig. 5 ).

[0025] First, an embodiment of a speaker according to the present disclosure will be described with reference to FIGS. 1 to 3. FIG.

[0026] FIG. 1 is a cross-sectional view of a speaker 10 according to this embodiment, taken along a plane passing through a central axis AX.

[0027] The speaker 10 is mounted, for example, on a side door of an automobile.

[0028] The speaker 10 has a structure that is symmetrical about a central axis AX in its main portion.

[0029] In the following description, the direction parallel to the central axis AX is referred to as the axial direction, one axial side is referred to as the upper side, and the other axial side is referred to as the lower side. The direction perpendicular to the central axis AX is referred to as the radial direction, with the radial side closer to the central axis AX being referred to as the radially inner side and the radial side farther from the central axis AX being referred to as the radially outer side.

[0030] The speaker 10 has a first vibrating part 20 that vibrates to produce sound, a second vibrating part 30 that vibrates to cancel out the vibration of the entire speaker 10 caused by the first vibrating part 20, a magnetic circuit 40, and a frame 50 that supports these.

[0031] (First Vibrating Section 20 ) The first vibrating section 20 includes a first bobbin 21 , a first coil 22 , a diaphragm 24 , an edge 25 , a cap 26 , and a first elastic support section 27 .

[0032] The first bobbin 21 has a cylindrical shape. The first coil 22 is formed on the outer peripheral surface of the lower end of the first bobbin 21.

[0033] The diaphragm 24 is a member that radiates sound by vibrating. The diaphragm 24 has a circular hole in the center and has a shape that extends radially outward and upward from the inner edge that forms the circular hole. The inner edge of the diaphragm 24 is bonded to the outer peripheral surface of the first bobbin 21. The outer edge of the diaphragm 24 is connected to the frame 50 via an edge 25. The edge 25 is made of rubber. The inner edge of the edge 25 is bonded to the outer edge of the diaphragm 24, and the outer edge of the edge 25 is bonded to the frame 50.

[0034] The cap 26 is a member that vibrates to radiate sound. The cap 26 covers the first bobbin 21 from above. The outer edge of the cap 26 is bonded to the upper surface of the diaphragm 24.

[0035] The first elastic support portion 27 elastically supports the first bobbin 21 so as to be displaceable in the axial direction. The first elastic support portion 27 is provided on the radially outer side of the first bobbin 21.

[0036] The first elastic support member 27 is composed of a single elastic body 27a. The elastic body 27a has a circular hole in the center and is an annular disk-shaped elastic body that extends radially outward from the inner edge that defines the circular hole. The elastic body 27a is made of cloth. The inner edge of the elastic body 27a is joined to the first bobbin 21, and the outer edge of the elastic body 27a is joined to the frame 50.

[0037] 2, the elastic body 27a has an inner edge portion 27a1 joined to the outer peripheral surface of the first bobbin 21, a wavy portion 27a2 having a plurality of wavy shapes arranged in the radial direction, and an outer edge portion 27a3 joined to the frame 50. The term "plural wavy shapes" as used here means a shape in which wavy shapes that are convex upward and wavy shapes that are convex downward are alternately repeated along the radial direction.

[0038] (Second Vibrating Part 30 ) The second vibrating part 30 has a second bobbin 31 , a second coil 32 and a second elastic support part 37 .

[0039] The second bobbin 31 has a cylindrical shape. The second bobbin 31 has a larger diameter than the first bobbin 21. The second coil 32 is formed on the outer peripheral surface of the lower end of the second bobbin 31. In the inactive state (the state in which the speaker 10 is not operating) shown in FIG. 1 , the upper end of the second bobbin 31 is located above the lower end of the first coil 22.

[0040] The second elastic support portion 37 elastically supports the second bobbin 31 so as to be displaceable in the axial direction. The second elastic support portion 37 is provided on the radially outer side of the second bobbin 31.

[0041] The second elastic support portion 37 includes an upper elastic body 38 a , a lower elastic body 38 b , and a second coupler 39 .

[0042] The upper elastic body 38a and the lower elastic body 38b are provided with an axial gap between them. The lower elastic body 38b is provided below the upper elastic body 38a. Both the upper elastic body 38a and the lower elastic body 38b have a circular hole in their centers and extend radially outward from the inner edge that defines the circular hole.

[0043] The inner edge of the second elastic support portion 37 is joined to the second bobbin 31. Specifically, the inner edge of the upper elastic body 38a and the lower elastic body 38b are joined to the second coupler 39. The second coupler 39 is joined to the outer peripheral surface of the second bobbin 31. In this way, the second coupler 39 connects the second bobbin 31 and the upper elastic body 38a, and also connects the second bobbin 31 and the lower elastic body 38b.

[0044] The upper elastic body 38a is made of cloth. As shown in Fig. 2, the upper elastic body 38a has an inner edge portion 38a1 joined to the second coupler 39, a wavy portion 38a2 having a plurality of wavy shapes arranged in the radial direction, and an outer edge portion 38a3 joined to the frame 50.

[0045] The lower elastic body 38b is made of rubber and has an inner edge portion 38b1 joined to the second coupler 39, a semicircular portion 38b2 having a substantially semicircular cross-sectional shape that is convex downward, and an outer edge portion 38b3 joined to the frame 50.

[0046] The second coupler 39 comprises an inner edge portion 39a joined to the second bobbin 31, an upper joining portion 39c joined to the upper elastic body 38a, a lower joining portion 39e joined to the lower elastic body 38b, a first connecting portion 39b connecting the inner edge portion 39a and the upper joining portion 39c, and a second connecting portion 39d connecting the upper joining portion 39c and the lower joining portion 39e.

[0047] The inner edge 39a has a shape that slopes downward toward the inside in the radial direction. The inner edge 39a is joined to the second bobbin 31 with an adhesive or the like (not shown). Since the inner edge 39a has a shape that slopes downward toward the inside in the radial direction, adhesive is allowed to accumulate on the upper side of the inner edge 39a.

[0048] The upper joint portion 39c has a cylindrical shape extending parallel to the axial direction. In other words, the thickness direction of the upper joint portion 39c is oriented in the radial direction. The outer peripheral surface of the upper joint portion 39c is joined to the upper elastic body 38a.

[0049] The lower joint portion 39e is located radially outward and below the upper joint portion 39c. The thickness direction of the lower joint portion 39e is oriented in the axial direction. The upper surface of the lower joint portion 39e is joined to the lower elastic body 38b.

[0050] The first connecting portion 39b radially connects the outer edge of the inner edge portion 39a to the lower end of the upper joint portion 39c. The thickness direction of the first connecting portion 39b is oriented in the axial direction.

[0051] The second connecting portion 39d connects the lower end of the upper joining portion 39c and the inner edge of the lower joining portion 39e. The second connecting portion 39d has a shape that slopes downward toward the outside in the radial direction.

[0052] The second coupler 39 may have a ventilation hole formed therein, penetrating the second coupler 39 in the thickness direction. The ventilation hole is formed, for example, in the first connecting portion 39b or the second connecting portion 39d.

[0053] The outer edge of the second elastic support member 37 is joined to the frame 50. Specifically, an outer edge 38a3 of the upper elastic body 38a is joined to the frame 50, and an outer edge 38b3 of the lower elastic body 38b is joined to the frame 50.

[0054] The second coupler 39 is, for example, a resin molded part, and is a member that is less likely to deform than the upper elastic body 38 a and the lower elastic body 38 b. Even if the second bobbin 31 is displaced in the axial direction, the relative positional relationship between the second bobbin 31, the second coil 32, and the second coupler 39 basically does not change.

[0055] In either the state where the second bobbin 31 is in the initial position (see FIG. 2 ) or the state where the second bobbin 31 is displaced (not shown), the upper joint portion 39c of the second coupler 39 is located above the upper end of the second coil 32. Therefore, in either of the above states, the inner edge portion 38a1 of the upper elastic body 38a is located above the upper end of the second coil 32.

[0056] In either the state where the second bobbin 31 is in the initial position or the state where the second bobbin 31 is displaced, the lower joint portion 39e of the second coupler 39 is located below the upper end of the second coil 32. Therefore, in either of the above states, the inner edge portion 38b1 of the lower elastic body 38b is located below the upper end of the second coil 32.

[0057] 3, the magnetic circuit 40 includes a first magnetic member 41, a first magnet 42, a second magnetic member 43, a third magnetic member 44, a second magnet 45, and a fourth magnetic member 46. These magnetic members 41, 43, 44, and 46 and the magnets 42 and 45 are joined together with an adhesive or the like.

[0058] The magnetic circuit 40 has a first magnetic gap G1 and a second magnetic gap G2. Both the first magnetic gap G1 and the second magnetic gap G2 are open on the upper side. The second magnetic gap G2 is located radially outward of the first magnetic gap G1.

[0059] The magnetic circuit 40 is composed of a first magnetic circuit 40A having a first magnetic gap G1 and a second magnetic circuit 40B having a second magnetic gap G2. The first magnetic circuit 40A is composed of a first magnetic member 41, a first magnet 42, and a second magnetic member 43, and the second magnetic circuit 40B is composed of a third magnetic member 44, a second magnet 45, and a fourth magnetic member 46.

[0060] The fourth magnetic member 46 has a bottom wall portion 46a, a cylindrical wall portion 46b extending upward from the outer edge of the bottom wall portion 46a, and a mounting portion 46d that is attached to the frame 50. The inner circumferential surface of the cylindrical wall portion 46b defines an outer surface G2b of the second magnetic gap G2. The bottom wall portion 46a has a through hole in its center. The mounting portion 46d protrudes radially outward from near the lower end of the cylindrical wall portion 46b.

[0061] The second magnet 45 is disposed on the upper surface of the bottom wall portion 46 a of the fourth magnetic member 46. The second magnet 45 is an annular magnet. The inner diameter of the second magnet 45, which is an annular magnet, is smaller than the inner diameter of the bottom wall portion 46 a, which has a through hole in the center.

[0062] The third magnetic member 44 has a bottom wall portion 44a and a cylindrical wall portion 44b extending upward from the outer edge of the bottom wall portion 44a. The outer peripheral surface of the cylindrical wall portion 44b defines the inner surface G2a of the second magnetic gap G2. The bottom wall portion 44a has a through hole in its center. The inner diameter of the bottom wall portion 44a is smaller than the inner diameter of the second magnet 45. Hereinafter, the third magnetic member 44 may be referred to as the inner magnetic member 44.

[0063] The second magnetic member 43 has a bottom wall portion 43a, a tubular wall portion 43b standing upward from the outer edge of the bottom wall portion 43a, a convex portion 43c protruding upward from the center of the bottom wall portion 43a, and an attachment portion 43d that is attached to the frame 50.

[0064] The inner circumferential surface of the cylindrical wall portion 43b has an outer forming surface G1b of the first magnetic gap G1. The attached portion 43d protrudes radially outward from near the upper end of the cylindrical wall portion 43b.

[0065] The first magnet 42 is disposed on the upper surface of the protrusion 43c of the second magnetic member 43. The first magnet 42 has a cylindrical shape.

[0066] The first magnetic member 41 is disposed on the upper surface of the first magnet 42. The first magnetic member 41 has a generally cylindrical shape. The outer peripheral surface of the first magnetic member 41 has an inner forming surface G1a of the first magnetic gap G1.

[0067] Specifically, the first magnetic member 41 has a substantially cylindrical main body 41a and a covering 41b that covers the main body 41a. The covering 41b covers a portion of the upper surface and the outer circumferential surface of the main body 41a. The covering 41b functions as the inner surface G1a of the first magnetic gap G1. The covering 41b is made of a non-magnetic material (copper, for example). The covering 41b suppresses the generation of eddy currents in the first magnetic gap G1.

[0068] (Frame 50 ) As shown in FIG. 1 , the frame 50 has a first bottom wall portion 51 , a second bottom wall portion 52 , a third bottom wall portion 53 , a fourth bottom wall portion 54 , and a magnetic circuit support portion 55 .

[0069] The first bottom wall portion 51 is located higher than the second bottom wall portion 52. The second bottom wall portion 52 is located higher than the third bottom wall portion 53. The third bottom wall portion 53 is located higher than the fourth bottom wall portion 54. The fourth bottom wall portion 54 is located higher than the magnetic circuit support portion 55.

[0070] The first bottom wall portion 51 supports the outer edge portion of the edge 25. The second bottom wall portion 52 supports the outer edge portion of the elastic body 27a of the first elastic support portion 27. The third bottom wall portion 53 supports the outer edge portion of the upper elastic body 38a of the second elastic support portion 37. The fourth bottom wall portion 54 supports the outer edge portion of the lower elastic body 38b of the second elastic support portion 37. The fifth bottom wall portion 55 supports the magnetic circuit 40. Hereinafter, the second bottom wall portion 52 may be referred to as the first mounting portion 52, and the third bottom wall portion 53 and the fourth bottom wall portion 54 may be referred to as the second mounting portions 53, 54.

[0071] The first bottom wall portion 51, the second bottom wall portion 52, the third bottom wall portion 53, and the fourth bottom wall portion 54 support respective support objects (such as the edge 25) on their upper surfaces. The magnetic circuit support portion 55 is mechanically fixed to the magnetic circuit 40.

[0072] The outer edge of the edge 25 is located radially outward of the outer edge of the elastic body 27 a of the first elastic support portion 27 .

[0073] An outer edge portion 38a3 of the upper elastic body 38a of the second elastic support portion 37 is located radially outward of an outer edge portion 38b3 of the lower elastic body 38b of the second elastic support portion 37. The outer edge portion 38b3 of the lower elastic body 38b of the second elastic support portion 37 is located radially outward of the attached portion 46d of the magnetic circuit 40.

[0074] The frame 50 has a first connecting portion 56 , a second connecting portion 57 , a third connecting portion 58 , and a fourth connecting portion 59 .

[0075] The first connecting portion 56 connects the first bottom wall portion 51 and the second bottom wall portion 52. The second connecting portion 57 connects the second bottom wall portion 52 and the third bottom wall portion 53. The third connecting portion 58 connects the third bottom wall portion 53 and the fourth bottom wall portion 54. The fourth connecting portion 59 connects the fourth bottom wall portion 54 and the magnetic circuit support portion 55.

[0076] The first connecting portion 56 has a first vertical wall 56a extending parallel to the axial direction, a first inclined wall 56b inclined with respect to the axial direction, and a first vertical wall 56c extending parallel to the axial direction. The second connecting portion 57 has a second vertical wall 57a extending parallel to the axial direction, a second radial wall 57b extending radially outward, a second inclined wall 57c inclined with respect to the axial direction, and a second vertical wall 57d extending parallel to the axial direction. The third connecting portion 58 has a third inclined wall 58a inclined with respect to the axial direction. The fourth connecting portion 59 has a fourth inclined wall 59a inclined with respect to the axial direction and a fourth bottom wall 59b perpendicular to the axial direction.

[0077] The frame 50 includes a first frame 50A, a second frame 50B, and a connecting frame 50C. The first frame 50A, the second frame 50B, and the connecting frame 50C are molded (resin molded) as separate bodies.

[0078] The first frame 50A has a first bottom wall portion 51, a first connecting portion 56, and a second bottom wall portion 52. The first frame 50A also has a magnetic circuit mounting portion 50A2 that supports the magnetic circuit 40, and a connecting portion 50A1 that connects the magnetic circuit mounting portion 50A2 and the second bottom wall portion 52. The connecting portion 50A1 has a shape that slopes radially inward toward the lower side. The magnetic circuit mounting portion 50A2 is located radially inward of the second bottom wall portion 52.

[0079] The second frame 50B has a third bottom wall portion 53 , a third connecting portion 58 , a fourth bottom wall portion 54 , a fourth connecting portion 59 and a magnetic circuit supporting portion 55 .

[0080] The connecting frame 50C has a second connecting portion 57 .

[0081] Although not shown, an air vent is formed in the first connecting portion 56. A plurality of the air vents are arranged in the circumferential direction. Specifically, the air vent is provided in the first inclined wall 56b. The specific structure in which the air vent is formed in the first connecting portion 56 is the same as that of the speaker 110 described below (see air vent 56H in Figures 5 and 6). On the other hand, no air vent is formed in the third connecting portion 58 and the fourth connecting portion 59 of the second frame 50B. This prevents water and the like from entering the second frame 50B.

[0082] Although not shown, the connecting portion 50A1 has a plurality of ventilation holes formed therein and arranged in a circumferential direction, thereby connecting the space below the first elastic support portion 27 in the first frame 50A to the space in the second frame 50B.

[0083] The connecting portion 50A1 is formed to be thinner than the first vertical wall 56a, thereby suppressing interference with the second bobbin 31. Note that, in the completed state of the speaker 10, the first magnetic circuit 40A is supported not only by the first frame 50A but also by the second frame 50B via the second magnetic circuit 40B. This makes it possible to form the first vertical wall 56a to be thinner and to form a large number of ventilation holes in the first vertical wall 56a.

[0084] Next, a method for manufacturing the speaker 10 of this embodiment will be described.

[0085] The manufacturing method of speaker 10 includes a first component assembly process for assembling first component 10A, a second component assembly process for assembling second component 10B, and a connecting process for connecting first component 10A and second component 10B. In other words, in the manufacturing method of this embodiment, first component 10A and second component 10B are assembled separately and then connected together. This allows first component 10A and second component 10B to be assembled on separate lines, resulting in speaker 10 that is well-suited for the manufacturing process.

[0086] The first component 10A includes a first vibrating part 20, a first magnetic circuit 40A, and a first frame 50A that supports the first vibrating part 20 and the first magnetic circuit 40A. The second component 10B includes a second vibrating part 30, a second magnetic circuit 40B, and a second frame 50B that supports the second vibrating part 30 and the second magnetic circuit 40B.

[0087] Next, the relationship between the magnetic circuit 40 and the first and second vibrating parts 20 and 30 will be described.

[0088] As shown in FIG. 1 , the first coil 22 of the first vibrating part 20 is disposed in the first magnetic gap G1. The first coil 22 is connected to a transmission path. The action of an electric signal from the transmission path and the magnetic field of the first magnetic gap G1 causes the first bobbin 21 to vibrate together with the first coil 22, which in turn causes the first vibrating part 20, including the diaphragm 24, to vibrate. This causes sound to be emitted. At this time, a vibration force is generated in the speaker 10 in response to the vibration of the first vibrating part 20. This vibration force is transmitted via the frame 50, causing the entire speaker 10 and the object to which the speaker 10 is attached (for example, the panel of a side door of an automobile) to vibrate.

[0089] The second coil 32 of the second vibrating part 30 is disposed in the second magnetic gap G2. The second coil 32 is connected to a transmission path, and the action of an electric signal from the transmission path and the magnetic field of the second magnetic gap G2 causes the second bobbin 31 to vibrate together with the second coil 32, which in turn causes the second vibrating part 30 to vibrate. The first vibrating part 20 and the second vibrating part 30 are configured to operate in opposite phases to each other. This cancels out the excitation forces generated in response to the vibration of the first vibrating part 20, thereby suppressing vibration of the entire speaker 10.

[0090] <Operation and Effect> Next, the operation and effect of this embodiment will be described.

[0091] 1 , the speaker 10 includes a first vibrating section 20, a second vibrating section 30, a magnetic circuit 40, and a frame 50. The frame 50 supports the first vibrating section 20, the second vibrating section 30, and the magnetic circuit 40. The first vibrating section 20 includes a first coil 22, a first bobbin 21 on which the first coil 22 is provided, and a first elastic support section 27 that elastically supports the first bobbin 21 so that the first bobbin 21 is displaceable in the axial direction. The second vibrating section 30 includes a second coil 32 having a larger diameter than the first coil 22, a second bobbin 31 on which the second coil 32 is provided, and a second elastic support section 37 that elastically supports the second bobbin 31 so that the second bobbin 31 is displaceable in the axial direction.

[0092] 1 , the magnetic circuit 40 includes a first magnetic circuit 40A having a first magnetic gap G1 in which the first coil 22 is disposed, and a second magnetic circuit 40B having a second magnetic gap G2 in which the second coil 32 is disposed. The frame 50 includes a first frame 50A to which the first vibrating part 20 and the first magnetic circuit 40A are attached, and a second frame 50B to which the second vibrating part 30 and the second magnetic circuit 40B are attached. Therefore, as shown in FIG. 4 , the speaker 10 can be manufactured by separately assembling a component (first component 10A) including the first vibrating part 20, the first magnetic circuit 40A, and the first frame 50A and a component (second component 10B) including the second vibrating part 30, the second magnetic circuit 40B, and the second frame 50B, and then combining the two components. In other words, the speaker 10 is manufactured with consideration given to the manufacturing process.

[0093] In this embodiment, as shown in FIG. 3 , the second magnetic circuit 40B includes an inner magnetic member 44 having an inner surface G2a defining the second magnetic gap G2. The inner magnetic member 44 includes a cylindrical wall portion 44b having the inner surface G2a defining the second magnetic gap G2 and a bottom wall portion 44a located radially inward of the cylindrical wall portion 44b. The first magnetic circuit 40A is disposed above the bottom wall portion 44a. Here, the bottom wall portion 44a is located below the upper end of the cylindrical wall portion 44b. Therefore, the magnetic circuit 40 can be made smaller in the axial direction than in a configuration in which the bottom wall portion 44a, above which the first magnetic circuit 40A is disposed, is not located below the upper end of the cylindrical wall portion 44b.

[0094] In this embodiment, as shown in FIG. 2 , the first frame 50A includes a first mounting portion 52 to which the first elastic support member 27 is attached, a magnetic circuit mounting portion 50A2 to which the first magnetic circuit 40A is attached, and a connecting portion 50A1 that connects the first mounting portion 52 and the magnetic circuit mounting portion 50A2. An air vent (not shown) is formed in the connecting portion 50A1. This allows the space below the first elastic support member 27 within the first frame 50A to communicate with the space within the second frame 50B. As a result, the influence of back pressure exerted when the second vibrating portion 30 vibrates can be reduced, suppressing the generation of abnormal noise such as wind noise. This also reduces distortion of acoustic characteristics.

[0095] In this embodiment, as shown in FIG. 4 , the frame 50 includes a connecting frame 50C connecting the first frame 50A and the second frame 50B. This increases the structural flexibility of the frame 50 compared to a configuration in which the first frame 50A and the second frame 50B are directly connected. For example, it is easy to realize a configuration in which the first mounting portion 52 of the first frame 50A is positioned radially inward relative to the second mounting portions 53 and 54 of the second frame 50B. Furthermore, it is easy to increase the inclination angle of the first inclined wall 56b relative to the axial direction. Increasing the inclination angle of the first inclined wall 56b relative to the axial direction results in a speaker 10 with excellent workability for wiring, etc. Furthermore, the first inclined wall 56b has ventilation holes, and increasing the inclination angle of the first inclined wall 56b relative to the axial direction allows these ventilation holes to be made larger. In the speaker 10, the opening area of ​​the ventilation holes in the first inclined wall 56b can be increased, ensuring a large amount of air escape on the back side of the diaphragm 24, thereby reducing the impact of air resistance when the first drive unit 20 vibrates.

[0096] 1, the second elastic support portion 37 includes an upper elastic body 38a and a lower elastic body 38b, so that the second vibrating portion 30 can vibrate in a stable position.

[0097] Incidentally, when the second elastic support portion 37 includes an upper elastic body 38a and a lower elastic body 38b, and the upper elastic body 38a and the lower elastic body 38b are each joined to the second bobbin 31, it is necessary to elongate the portion of the second bobbin 31 that is located outside the magnetic circuit 40 in the axial direction. This results in an increase in the axial size of the second vibrating portion 30, and therefore an increase in the overall size of the speaker 10. Therefore, in this embodiment, as shown in FIG. 2 , the second vibrating portion 30 further includes a second coupler 39 that connects the second bobbin 31 and the upper elastic body 38a and also connects the second bobbin 31 and the lower elastic body 38b. Therefore, the upper elastic body 38a and the lower elastic body 38b are connected to the second bobbin 31 via the second coupler 39. Therefore, it is not necessary to elongate the portion of the second bobbin 31 that is located outside the magnetic circuit 40 in the axial direction, and this allows the speaker 10 to be made smaller in size in the axial direction.

[0098] 2, in the inactive state, the entire lower elastic body 38b is located below the upper end of the second coil 32. Therefore, the space radially outward from the magnetic circuit 40 and below the upper end of the second magnetic gap G2 can be effectively used as the space in which the lower elastic body 38b is disposed.

[0099] In this embodiment, an air hole may be formed in the second coupler 39 between the connection position (upper joint 39c) of the upper elastic body 38a and the connection position (lower joint 39e) of the lower elastic body 38b, thereby reducing the effect of back pressure that the second vibrating part 30 receives when vibrating.

[0100] However, if the second coil 32 has a larger diameter than the first coil 22, it is difficult to ensure the diameter dimension (the distance from the inner edge to the outer edge of the second elastic support portion 37) of the second elastic support portion 37 that elastically supports the second bobbin 31. Therefore, in this embodiment, as shown in FIG. 2 , the portion of the first frame 50A that supports the first elastic support portion 27 (first mounting portion 52) is located radially inward of the portion of the second frame 50B that supports the second elastic support portion 37 (second mounting portions 53, 54). This makes it easier to ensure the diameter dimension of the second elastic support portion 37.

[0101] Furthermore, in this embodiment, as shown in FIG. 1 , the underside of the magnetic circuit 40 is exposed and not covered by the frame 50. This allows the speaker 10 to be miniaturized in the axial direction. In particular, in this embodiment, the speaker 10 is mounted in a side door of a vehicle, and the underside (lower side) of the speaker 10 faces the exterior of the vehicle. Therefore, to prevent water from accumulating in the recess formed in the underside (lower side) of the magnetic circuit 40, the recess is shaped so that its diameter gradually increases toward the bottom. This allows water that has entered the recess to be easily drained. Specifically, the recess 43e formed in the underside of the second magnetic member 43, the through-hole formed in the center of the bottom wall portion 44a, the through-hole in the second magnet 45, which is an annular magnet, and the through-hole formed in the center of the bottom wall portion 46a are shaped so that their diameters increase in this order.

[0102] 1, in this embodiment, the first vibrating section 20 is a driving section for producing sound, and the second vibrating section 30 is a driving section for canceling out vibration of the entire speaker 10 caused by the first vibrating section 20. Therefore, vibration of the entire speaker 10 can be suppressed.

[0103] Next, another embodiment of a speaker according to the present disclosure will be described with reference to FIGS. 5 and 6. FIG.

[0104] 5 is a cross-sectional view of the speaker 110 according to this embodiment taken along a plane passing through the central axis AX. The configuration of the speaker 110 is largely the same as that of the speaker 10 already described, and therefore the same components are designated by the same reference numerals and detailed description thereof will be omitted.

[0105] The speaker 110 has a first vibrating part 20 that vibrates to produce sound, a second vibrating part 30 that vibrates to cancel out the vibration of the entire speaker 110 caused by the first vibrating part 20, a magnetic circuit 40, and a frame 50 that supports these.

[0106] The first vibrating part 20 includes a first bobbin 21 , a first coil 22 , a diaphragm 24 , an edge 25 , a cap 26 and a first elastic support part 27 .

[0107] The second vibrating part 30 has a second bobbin 31 , a second coil 32 and a second elastic support part 37 .

[0108] The second elastic support portion 37 includes an upper elastic body 38 a , a lower elastic body 38 b , and a second coupler 39 .

[0109] The upper elastic body 38a is made of cloth, and the lower elastic body 38b is made of rubber. By making one of the upper elastic body 38a and the lower elastic body 38b of rubber in the second elastic support portion 37, it is possible to suppress sagging of the second elastic support portion 37 as a whole, compared to, for example, an embodiment in which both the upper elastic body and the lower elastic body are made of cloth. Furthermore, by making one of the upper elastic body 38a and the lower elastic body 38b of the second elastic support portion 37 of cloth, it is possible to improve the center holding force of the second elastic support portion with respect to the second bobbin 31, compared to, for example, an embodiment in which both the upper elastic body and the lower elastic body are made of rubber.

[0110] Furthermore, the first bobbin 21 is elastically supported not only by the first elastic support portion 27 including the elastic body 27a made of cloth, but also by the edge 25 made of rubber. In this configuration, by making one of the upper elastic body 38a and the lower elastic body 38b of the second elastic support portion 37 out of rubber, it is possible to match the characteristic changes over time between the member that elastically supports the first bobbin 21 and the member that elastically supports the second bobbin 31. This makes it possible to suppress deterioration in the performance of the second vibrating portion 30 (i.e., the function of canceling out the vibration of the entire speaker 10 caused by the first vibrating portion 20).

[0111] The second connecting portion 39d of the second coupler 39 is formed with an air hole 39H that penetrates the second coupler 39 in the thickness direction.

[0112] (Magnetic Circuit 40) As shown in FIG. 5, the magnetic circuit 40 includes a first magnetic member 41, a first magnet 42, a second magnetic member 43, a third magnetic member 44, a second magnet 45, and a fourth magnetic member 46.

[0113] The magnetic circuit 40 has a first magnetic gap G1 and a second magnetic gap G2.

[0114] The magnetic circuit 40 is composed of a first magnetic circuit 40A having a first magnetic gap G1 and a second magnetic circuit 40B having a second magnetic gap G2. The first magnetic circuit 40A is composed of a first magnetic member 41, a first magnet 42, and a second magnetic member 43, while the second magnetic circuit 40B is composed of a third magnetic member 44, a second magnet 45, and a fourth magnetic member 46. The magnetic circuit 40 includes a screw 49 that connects the first magnetic circuit 40A and the second magnetic circuit 40B. The screw 49 is made of a non-magnetic material. This prevents the screw 49 from being attracted to the magnetic circuits 40A and 40B, improving assembly ease compared to when the screw 49 is made of a magnetic material. The screw 49 connects the second magnetic member 43 of the first magnetic circuit 40A and the third magnetic member 44 of the second magnetic circuit 40B.

[0115] (Frame 50 ) As shown in FIG. 5 , the frame 50 has a first bottom wall portion 51 , a second bottom wall portion 52 , a third bottom wall portion 53 , a fourth bottom wall portion 54 , and a magnetic circuit support portion 55 .

[0116] The first bottom wall portion 51 supports the outer edge portion of the edge 25. The second bottom wall portion 52 supports the outer edge portion of the elastic body 27a of the first elastic support portion 27. The third bottom wall portion 53 supports the outer edge portion of the upper elastic body 38a of the second elastic support portion 37. The fourth bottom wall portion 54 supports the outer edge portion of the lower elastic body 38b of the second elastic support portion 37. The fifth bottom wall portion 55 supports the magnetic circuit 40. Hereinafter, the second bottom wall portion 52 may be referred to as the first mounting portion 52, and the third bottom wall portion 53 and the fourth bottom wall portion 54 may be referred to as the second mounting portions 53, 54.

[0117] The frame 50 has a first connecting portion 56 , a second connecting portion 57 , a third connecting portion 58 , and a fourth connecting portion 59 .

[0118] The first connecting portion 56 connects the first bottom wall portion 51 and the second bottom wall portion 52. The second connecting portion 57 connects the second bottom wall portion 52 and the third bottom wall portion 53. The third connecting portion 58 connects the third bottom wall portion 53 and the fourth bottom wall portion 54. The fourth connecting portion 59 connects the fourth bottom wall portion 54 and the magnetic circuit support portion 55.

[0119] The frame 50 includes a first frame 50A, a second frame 50B, and a connecting frame 50C. The first frame 50A, the second frame 50B, and the connecting frame 50C are molded (resin molded) as separate bodies.

[0120] The frame 50 has a first connection portion 56 connecting the first bottom wall portion 51 and the second bottom wall portion 52, and a vent hole 56H is formed in the first connection portion 56. As shown in FIG. 6 , a plurality of the vent holes 56H are arranged in a circumferential direction. Specifically, the vent hole 56H is provided in the first inclined wall 56b. In other words, the first connection portion 56 includes a plurality of beam portions 56L arranged in the circumferential direction, and the vent hole 56H is formed between adjacent beam portions 56L, 56L. On the other hand, no vent hole is formed in the third connection portion 58 and the fourth connection portion 59 of the second frame 50B. This prevents water and the like from entering the second frame 50B. The frame 50 includes a connecting frame 50C connecting the first frame 50A and the second frame 50B, so that the connection position between the first frame 50A and the connecting frame 50C can be positioned radially inward of the connection position between the second frame 50B and the connecting frame 50C. This allows the opening area of ​​the ventilation hole 56H to be larger than in a configuration in which the first frame 50A and the second frame 50B are directly connected. The ventilation hole 56H ensures a large amount of air escape on the back side of the diaphragm 24, and reduces the effect of air resistance when the first drive unit 20 vibrates.

[0121] The first frame 50A has a magnetic circuit mounting portion 50A2 that supports the magnetic circuit 40 and a connection portion 50A1 that connects the magnetic circuit mounting portion 50A2 and the second bottom wall portion 52. As shown in FIG. 6 , a ventilation hole 50A1H is formed in the connection portion 50A1. A plurality of ventilation holes 50A1 are provided and aligned in the circumferential direction. The ventilation hole 50A1H connects the space below the first elastic support member 27 in the first frame 50A to the space in the second frame 50B.

[0122] The frame 50 has a cover portion 50A3. The cover portion 50A3 is provided on the first frame 50A. The cover portion 50A3 is located radially outward of the second frame 50B. The lower end of the cover portion 50A3 is located lower than the upper end of the second frame 50B. The cover portion 50A3 prevents water from entering the interior of the speaker 110.

[0123] Next, a method for manufacturing the speaker 110 of this embodiment will be described.

[0124] The manufacturing method of speaker 110 includes a first component assembly process for assembling first component 10A, a second component assembly process for assembling second component 10B, and a connecting process for connecting first component 10A and second component 10B. In other words, in the manufacturing method of this embodiment, first component 10A and second component 10B are assembled separately and then connected together. This allows first component 10A and second component 10B to be assembled on separate lines, resulting in speaker 110 that is well-suited for the manufacturing process.

[0125] The first frame 50A, the second frame 50B, and the connecting frame 50C are joined together with an adhesive. A gap 80 is formed between the first frame 50A and the connecting frame 50C, and this gap is filled with adhesive. This allows the frames 50A, 50B, and 50C to be joined together while the first magnetic circuit 40A and the second magnetic circuit 40B are securely in contact with each other in the vertical direction.

[0126] [Supplementary Explanation] Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments.

[0127] In the above embodiment, the upper elastic body 38a is made of cloth and the lower elastic body 38b is made of rubber. However, the present disclosure is not limited to this. The upper elastic body 38a may be made of rubber and the lower elastic body 38b may be made of cloth. Furthermore, both the upper elastic body 38a and the lower elastic body 38b may be made of cloth or both may be made of rubber.

[0128] REFERENCE SIGNS LIST 10 Speaker 20 First vibrating portion 21 First bobbin 22 First coil 27 First elastic support portion 30 Second vibrating portion 31 Second bobbin 32 Second coil 37 Second elastic support portion 38a Upper elastic body 38b Lower elastic body 39 Second coupler 40 Magnetic circuit 40A First magnetic circuit 40B Second magnetic circuit 44 Third magnetic member (inner magnetic member) 44a Bottom wall portion 44b Cylindrical wall portion 50 Frame 50A First frame 50A1 Connection portion 50A2 Magnetic circuit mounting portion 50B Second frame 50C Connecting frame 52 Second bottom wall portion (first mounting portion) 53 Third bottom wall portion (second mounting portion) 54 Fourth bottom wall portion (second mounting portion) G1 First magnetic gap G1a Inner forming surface G1b Outer forming surface G2 Second magnetic gap G2a Inner forming surface G2b Outer forming surface

Claims

1. A speaker comprising: a first vibrating part; a second vibrating part; a magnetic circuit; and a frame supporting the first vibrating part, the second vibrating part, and the magnetic circuit, wherein the first vibrating part comprises: a first coil; a first bobbin on which the first coil is provided; and a first elastic support part that elastically supports the first bobbin so that it can be displaced in the axial direction; the second vibrating part comprises: a second coil having a diameter larger than that of the first coil; a second bobbin on which the second coil is provided; and a second elastic support part that elastically supports the second bobbin so that it can be displaced in the axial direction; the magnetic circuit comprises: a first magnetic circuit having a first magnetic gap in which the first coil is disposed; and a second magnetic circuit having a second magnetic gap in which the second coil is disposed; and the frame comprises: a first frame on which the first vibrating part and the first magnetic circuit are attached; and a second frame on which the second vibrating part and the second magnetic circuit are attached.

2. A speaker as described in claim 1, wherein the second magnetic circuit comprises an inner magnetic member having an inner forming surface of the second magnetic gap, the inner magnetic member comprising a cylindrical wall portion having the inner forming surface of the second magnetic gap, and a bottom wall portion located radially inward from the cylindrical wall portion, the first magnetic circuit being arranged above the bottom wall portion, and the bottom wall portion being located below the upper end of the cylindrical wall portion.

3. A speaker as described in claim 1, wherein the first frame comprises: a first mounting portion to which the first elastic support portion is attached; a magnetic circuit mounting portion to which the first magnetic circuit is attached; and a connecting portion that connects the first mounting portion and the magnetic circuit mounting portion, and an air vent is formed in the connecting portion.

4. The speaker according to claim 1, wherein the frame comprises a connecting frame that connects the first frame and the second frame.

5. A speaker as described in claim 1, wherein the second elastic support portion comprises: an upper elastic body; a lower elastic body provided below the upper elastic body; and a second coupler that connects the second bobbin and the upper elastic body and also connects the second bobbin and the lower elastic body.

6. The speaker according to claim 5, wherein at least a portion of the lower elastic body is located below an upper end of the second coil.

7. The speaker according to claim 5, wherein the second coupler has an air hole formed between the connection position of the upper elastic body and the connection position of the lower elastic body.

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