Speaker

Abstract

To provide a down-sized speaker including a first vibration part and a second vibration part.SOLUTION: A speaker 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 gap G1 and a second magnetic gap G2. The magnetic circuit 40 includes: a first magnet 42 arranged on inward in a radial direction with respect to the first magnetic gap G1; and a ring-shaped second magnet 44. The ring-shaped second magnet 44 is arranged outward in the radial direction with respect to the second magnetic gap G2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a speaker. [Background technology]

[0002] The speaker disclosed in Patent Document 1 includes a first vibrating portion for emitting sound, as well as a second vibrating portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2023 / 090124 Summary of the Invention [Problem to be solved by the invention]

[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 compact. [Means for solving the problem]

[0005] A speaker according to a first aspect is a speaker comprising a first vibration section, a second vibration section, a magnetic circuit, and a frame supporting the first vibration section, the second vibration section, and the magnetic circuit, wherein the first vibration section comprises a first coil, a first bobbin on which the first coil is provided, and a first elastic support portion that elastically supports the first bobbin so as to be displaceable in the axial direction, the second vibration section 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 portion that elastically supports the second bobbin so as to be displaceable in the axial direction, the magnetic circuit comprises a first magnetic gap in which the first coil is disposed, and a second magnetic gap in which the second coil is disposed, the first magnetic gap being open to an upper side that is one axial side, and the second magnetic gap being open to an upper side that is one axial side, and the magnetic circuit comprises a first magnet disposed radially inward of the first magnetic gap, and a ring-shaped second magnet disposed radially outward of the second magnetic gap.

[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 that it can be displaced in the axial direction. The second vibration section includes 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 section that elastically supports the second bobbin so that it can be displaced in the axial direction. The magnetic circuit includes a first magnetic gap in which the first coil is disposed, and a second magnetic gap in which the second coil is disposed. The first magnetic gap is open to one axial side, and the second magnetic gap is open to one axial side.

[0007] In this aspect, the magnetic circuit includes a first magnet disposed radially inward of the first magnetic gap, and an annular second magnet. Therefore, compared to a configuration in which the magnetic circuit includes only one of the first magnet and the second magnet, it is possible to ensure a high magnetic flux density in the first magnetic gap and the second magnetic gap.

[0008] In this embodiment, the annular second magnet is disposed radially outward of the second magnetic gap. Therefore, the second magnetic gap is located radially inward of the inner circumferential surface of the annular second magnet. This makes it easier to reduce the diameter of the second coil disposed in the second magnetic gap. Reducing the diameter of the second coil also reduces the diameter of the second bobbin, allowing for more effective use of the space radially outward of the second bobbin. As a result, it is easier to miniaturize the speaker.

[0009] In the embodiment described below, the first vibrating section is a vibrating section for emitting sound, and the second vibrating section is a vibrating section for canceling out vibration of the entire speaker caused by the first vibrating section. However, the first vibrating section and the second vibrating section in this embodiment are not limited to these vibrating sections. For example, both the first vibrating section and the second vibrating section may be vibrating sections for emitting sound. Alternatively, the second vibrating section may be a vibrating section for emitting sound, and the first vibrating section may be a vibrating section for canceling out vibration of the entire speaker caused by the second vibrating section.

[0010] In the speaker of the second aspect, in the first aspect, the magnetic circuit includes a common magnetic member having a cylindrical wall portion extending in the axial direction, the radially inner surface of the cylindrical wall portion has an outer forming surface that forms the first magnetic gap, and the radially outer surface of the cylindrical wall portion has an inner forming surface that forms the second magnetic gap.

[0011] In this aspect, the magnetic circuit includes a common magnetic member having a cylindrical wall portion extending in the axial direction. Here, the radially inner surface of the cylindrical wall portion has an outer forming surface that forms the first magnetic gap, and the radially outer surface of the cylindrical wall portion has an inner forming surface that forms the second magnetic gap. Therefore, the cylindrical wall portion of the common magnetic member can be used in common by the magnetic circuit for the first magnetic gap and the magnetic circuit for the second magnetic gap.

[0012] A speaker according to a third aspect is the speaker according to the second aspect, wherein the common magnetic member has an outer bottom wall portion that protrudes radially outward from the cylindrical wall portion, and the second magnet is arranged on one axial side of the outer bottom wall portion.

[0013] In this aspect, the common magnetic member includes an outer bottom wall portion that protrudes radially outward from the cylindrical wall portion, and the second magnet is disposed on one axial side of the outer bottom wall portion. Therefore, the number of parts can be reduced compared to an embodiment in which the outer bottom wall portion on which the second magnet is arranged on one axial side is formed as a separate body from the common magnetic member.

[0014] In the embodiment described below, the surface on the other axial side of the cylindrical wall portion and the surface on the other axial side of the outer bottom wall portion are flush with each other. However, this aspect is not limited to this, and a step may be provided between the surface on the other axial side of the cylindrical wall portion and the surface on the other axial side of the outer bottom wall portion.

[0015] A speaker according to a fourth aspect is any one of the first to third aspects, wherein the magnetic circuit comprises an annular magnetic member, the annular magnetic member having an outer forming surface that forms the second magnetic gap and an abutment surface that abuts against the second magnet, and the radially inner end of the abutment surface is located radially outward from the outer forming surface of the second magnetic gap.

[0016] In this aspect, the magnetic circuit includes an annular magnetic member having an outer surface that defines the second magnetic gap and an abutment surface that abuts against the second magnet. Here, the radially inner end of the contact surface is located radially outward of the outer defining surface of the second magnetic gap. Therefore, interference between the second coil and the annular magnetic member can be suppressed.

[0017] A speaker according to a fifth aspect is any one of the first to fourth aspects, wherein the second elastic support portion comprises a one-side elastic body, a other-side elastic body that is provided on the other axial side of the one-side elastic body, and a second coupler that connects the second bobbin and the one-side elastic body and also connects the second bobbin and the other-side elastic body.

[0018] In this aspect, the second elastic support portion includes a one-side elastic body and an other-side elastic body. Therefore, the second vibrating part can be vibrated in a stable posture.

[0019] When the second elastic support portion includes a first elastic body and an second elastic body, and the first elastic body and the second elastic body are each joined to the second bobbin, the portion of the second bobbin that is located outside the magnetic circuit must be made long in the axial direction, which leads to an increase in the axial size of the second vibrating portion and therefore the size of the entire speaker. Therefore, in this aspect, the second vibrating section includes a second coupler that connects the second bobbin and the one-side elastic body and also connects the second bobbin and the other-side elastic body. Therefore, the one-side elastic body and the other-side elastic body are connected to the second bobbin via the second coupler, which eliminates the need to make the portion of the second bobbin located outside the magnetic circuit long in the axial direction, making it easier to reduce the speaker's size in the axial direction.

[0020] A sixth aspect of the present invention relates to the speaker of the fifth aspect, and is characterized in that at least a portion of the other-side elastic body is located on the other axial side of the one axial end of the second coil.

[0021] In this aspect, at least a portion of the other-side elastic body is located on the other axial side of the one axial end of the second coil. Therefore, the space radially outward from the magnetic circuit and on the other axial side of the one axial end of the second magnetic gap can be effectively used as a space in which the other-side elastic body is disposed.

[0022] In the embodiment described below, the entire other-side elastic body is located on the other axial side of the one axial 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 other-side elastic body may be located on the other axial side of the one axial end of the second coil, and the other-side elastic body may have a portion that is not located on the other axial side of the one axial end of the second coil.

[0023] A speaker according to a seventh aspect is any one of the first to sixth aspects, wherein an air hole is formed in the second coupler between the connection position of the one-side elastic body and the connection position of the other-side elastic body.

[0024] In this aspect, the second coupler has an air hole formed between the connection position of the one side elastic body and the connection position of the other side elastic body. Therefore, it is possible to reduce the influence of back pressure that is exerted when the second vibrating portion vibrates.

[0025] A speaker according to an eighth aspect is any one of the first to seventh aspects, wherein the first elastic support portion has a recess for avoiding interference with the second bobbin.

[0026] In this aspect, the first elastic support portion has a recess for avoiding interference with the second bobbin. This allows the first vibrating portion and the second vibrating portion to be closer to each other in the axial direction, which makes it easier to reduce the size of the speaker in the axial direction.

[0027] In the embodiment described below, the recess is formed in the first coupler included in the first elastic support member. However, this aspect is not limited to this, and the recess may be formed in the elastic body included in the first elastic support member. In this case, the first elastic support member does not need to include the first coupler.

[0028] A speaker according to a ninth aspect is any one of the first to seventh aspects, wherein the first elastic support portion comprises an elastic body and a first coupler that connects the elastic body and the first bobbin, and the first coupler has a recess for avoiding interference with the second bobbin.

[0029] In this aspect, the first elastic support portion includes an elastic body and a first coupler that connects the elastic body to the first bobbin, and the first coupler has a recess that prevents interference with the second bobbin. Therefore, compared to an embodiment in which the elastic body has a recess, the recess can be formed to be less likely to deform.

[0030] A speaker according to a tenth aspect is the speaker according to the ninth aspect, wherein the first vibrating portion includes a diaphragm, and the diaphragm is connected to the first bobbin without the first coupler interposed therebetween.

[0031] In this aspect, the first vibrating section includes a diaphragm that is coupled to the first bobbin without the first coupler. Therefore, compared to a configuration in which the diaphragm is connected to the first bobbin via the first coupler, the vibration of the first bobbin can be transmitted more directly to the diaphragm.

[0032] A speaker according to an eleventh aspect is any one of the first to tenth aspects, wherein the magnetization direction of the first magnet and the magnetization direction of the second magnet are both along the axial direction and are opposite to each other.

[0033] In this embodiment, the magnetization direction of the first magnet and the magnetization direction of the second magnet are both axially aligned and opposite to each other. This makes it easy to ensure the magnetic flux density in the first magnetic gap and the second magnetic gap. [Effects of the Invention]

[0034] 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 is small in size. [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a cross-sectional view of a speaker according to an embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view of the speaker according to the embodiment. [Figure 3] FIG. 2 is a cross-sectional view of a magnetic circuit according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0036] First, an embodiment of a speaker according to the present disclosure will be described with reference to FIGS.

[0037] 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.

[0038] The speaker 10 is mounted, for example, on a side door of an automobile.

[0039] The speaker 10 has a structure that is symmetrical about a central axis AX in its main portion.

[0040] 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 referred to as the axial inner side and the radial side away from the central axis AX referred to as the axial outer side.

[0041] 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.

[0042] (First vibration section 20) The first vibrating part 20 has a first bobbin 21 , a first coil 22 , a diaphragm 24 , an edge 25 , a cap 26 and a first elastic support part 27 .

[0043] 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.

[0044] The diaphragm 24 is a member that radiates sound by vibrating. The diaphragm 24 has a circular hole in the center and extends radially outward and upward from the inner edge that defines the circular hole. The inner edge of the diaphragm 24 is joined 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.

[0045] 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 joined to the upper surface of the diaphragm 24.

[0046] 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.

[0047] The first elastic support portion 27 includes a single elastic body 27a and a first coupler 29 that connects the elastic body 27a and the first bobbin 21 together.

[0048] The elastic body 27a is an annular disk-shaped elastic body having a circular hole in the center and extending radially outward from the inner edge that defines the circular hole. The elastic body 27a is made of fabric.

[0049] 2, the elastic body 27a has an inner edge portion 27a1 joined to the first coupler 29, 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. Here, the plurality of wavy shapes 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.

[0050] The first coupler 29 has an inner edge portion 29a joined to the first bobbin 21, recessed portions 29c, 29d, and 29e, and a connecting portion 29b connecting the inner edge portion 29a and the recessed portions 29c, 29d, and 29e.

[0051] The recesses 29c, 29d, and 29e each include an inner wall 29c, an outer wall 29e, and a top wall 29d that connects the upper end of the inner wall 29c to the upper end of the outer wall 29e. As a result, the recesses 29c, 29d, and 29e have a shape that is recessed upward and functions to prevent interference between the first coupler 29 and the second bobbin 31 when they approach each other in the axial direction.

[0052] The upper ends of recesses 29c, 29d, and 29e are located above inner edge 29a. The lower ends of recesses 29c, 29d, and 29e are located below inner edge 29a. The lower ends of recesses 29c, 29d, and 29e are the lower end of inner wall 29c.

[0053] Additionally, the outer wall 29e of the first coupler 29 is joined to the inner edge portion 27a1 of the elastic body 27a.

[0054] The first coupler 29 is, for example, a resin molded product, and is a member that is less likely to deform than the elastic body 27a. Even if the first bobbin 21 is displaced in the axial direction, the relative positional relationship between the first bobbin 21, the first coil 22, and the first coupler 29 basically does not change.

[0055] In either the state where the first bobbin 21 is in the initial position (see Figure 2) or the state where the first bobbin 21 is displaced (not shown), the inner edge portion 29a of the first coupler 29 is located below the inner edge portion 27a1 of the elastic body 27a.

[0056] When the first bobbin 21 is in the initial position (see FIG. 2), the inner edge 29a of the first coupler 29 is located below the outer edge 27a3 of the elastic body 27a.

[0057] (Second vibrating section 30) The second vibrating part 30 has a second bobbin 31 , a second coil 32 and a second elastic support part 37 .

[0058] 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 inoperative state (a 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 upper end of the first coil 22.

[0059] 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.

[0060] The second elastic support portion 37 includes a first elastic body 38 a, a second elastic body 38 b, and a second coupler 39 .

[0061] The one-side elastic body 38a and the other-side elastic body 38b are provided with an axial gap between them. The other-side elastic body 38b is provided on the other axial side of the one-side elastic body 38a. Both the one-side elastic body 38a and the other-side elastic body 38b are annular disk-shaped elastic bodies that have a circular hole in their centers and extend radially outward from the inner edge forming the circular hole. The inner edge portions of the one-side elastic body 38a and the other-side elastic body 38b are joined to a second coupler 39. The second coupler 39 is joined to the outer peripheral surface of the second bobbin 31. As a result, the second coupler 39 connects the second bobbin 31 and the one-side elastic body 38a, and also connects the second bobbin 31 and the other-side elastic body 38b.

[0062] 2, the first elastic body 38a is made of cloth and has an inner edge 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 38a3.

[0063] The other elastic body 38b is made of rubber and has an inner edge portion 38b1 that is joined to the second coupler 39, a semicircular portion 38b2 that has a substantially semicircular cross-sectional shape that is convex downward, and an outer edge portion 38b3.

[0064] The outer edge of the second elastic support portion 37 is joined to the frame 50 . Specifically, an outer edge portion 38b3 of the other-side elastic body 38b is directly joined to the frame 50. An outer edge portion 38a3 of the one-side elastic body 38a is joined to the frame 50 via the spacer 38c and the outer edge portion 38b3 of the other-side elastic body 38b.

[0065] The second coupler 39 comprises an inner edge portion 39a joined to the second bobbin 31, a one-side joint portion 39c joined to the one-side elastic body 38a, an other-side joint portion 39e joined to the other-side elastic body 38b, a first connection portion 39b connecting the inner edge portion 39a and the one-side joint portion 39c, and a second connection portion 39d connecting the one-side joint portion 39c and the other-side joint portion 39e.

[0066] The inner edge portion 39a has a shape that slopes downward toward the inside in the radial direction. The inner edge portion 39a is bonded to the second bobbin 31 with an adhesive or the like (not shown).

[0067] The first joint portion 39c has a cylindrical shape extending parallel to the axial direction. In other words, the thickness direction of the first joint portion 39c is oriented in the radial direction. The outer peripheral surface of the first joint portion 39c is joined to the first elastic body 38a.

[0068] The other-side joint portion 39e is located radially outward and below the one-side joint portion 39c. The thickness direction of the other-side joint portion 39e is oriented in the axial direction. The upper surface of the other-side joint portion 39e is joined to the other-side elastic body 38b.

[0069] The first connecting portion 39b connects the outer edge of the inner edge portion 39a and the one-side joining portion 39c in the radial direction. The thickness direction of the first connecting portion 39b is oriented in the axial direction.

[0070] The second connecting portion 39d connects the lower end of the one-side connecting portion 39c to the inner edge of the other-side connecting portion 39e. The second connecting portion 39d has a curved shape such that the inclination angle relative to the radial direction increases as it goes radially outward. This prevents interference with the magnetic circuit 40. The other-side connecting portion 39e is located radially outward of a second magnet 44 of the magnetic circuit 40, which will be described later.

[0071] Although not shown in the drawings, a through-hole is formed in the second coupler 39, penetrating the second coupler 39 in the thickness direction. This through-hole is formed in the second connection portion 39d.

[0072] The second coupler 39 is, for example, a resin molded part, and is a member that is less likely to deform than the one-side elastic body 38 a and the other-side 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.

[0073] 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 one-side 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 one-side elastic body 38a is located above the upper end of the second coil 32.

[0074] 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 other-side 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 other-side elastic body 38b is located below the upper end of the second coil 32.

[0075] (Magnetic circuit 40) 3, the magnetic circuit 40 includes a first magnetic member 41, a first magnet 42, a second magnetic member 43 (annular magnetic member 43), a second magnet 44, and a third magnetic member 45 (shared magnetic member 45). These magnetic members 41, 43, and 45 and the magnets 42 and 44 are joined together with an adhesive or the like.

[0076] 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.

[0077] The magnetic circuit 40 is integrally formed. That is, the magnetic circuit 40 includes the first magnetic gap G1 and the second magnetic gap G2.

[0078] The magnetic circuit 40 forms a first magnetic path 71. The first magnetic path 71 is a magnetic path that passes through both the first magnetic gap G1 and the second magnetic gap G2. The magnetic circuit 40 also forms a second magnetic path 72. The first magnetic path 72 is a magnetic path that passes only through the first magnetic gap G1 out of the first magnetic gap G1 and the second magnetic gap G2.

[0079] The third magnetic member 45 has a bottom wall portion 45a, a cylindrical wall portion 45b standing upward from the outer edge of the bottom wall portion 45a, a convex portion 45c protruding upward from the center of the bottom wall portion 45a, an outer bottom wall portion 45e protruding radially outward from the cylindrical wall portion 45b, and an attachment portion 45d that is attached to the frame 50.

[0080] The lower surfaces of the bottom wall portion 45a, the cylindrical wall portion 45b, and the outer bottom wall portion 45e are flush with each other. However, a step may be formed between the lower surfaces of the cylindrical wall portion 45b and the outer bottom wall portion 45e. The mounting portion 45d protrudes radially outward from the radially outer end of the outer bottom wall portion 45e.

[0081] The protrusion 45c of the third magnetic member 45 is formed as a separate body from the other parts of the third magnetic member 45. In other words, the protrusion 45c formed as a separate body is disposed on the upper surface of the central part of the bottom wall portion 45a, thereby providing the protrusion 45c that protrudes upward from the central part of the bottom wall portion 45a. However, the present disclosure is not limited to this, and the protrusion 45c of the third magnetic member 45 may be formed integrally with the other parts of the third magnetic member 45.

[0082] The first magnet 42 is disposed on the upper surface of the protrusion 45c of the third magnetic member 45. The first magnet 42 has a cylindrical shape.

[0083] The second magnet 44 is disposed on the upper surface of the outer bottom wall portion 45e of the third magnetic member 45. The second magnet 44 is an annular magnet. The second magnet 44, which is an annular magnet, is disposed so as to surround the cylindrical wall portion 45b of the third magnetic member 45.

[0084] The second magnetic member 43 is disposed on the upper surface of the second magnet 44. The second magnetic member 43 has a tubular portion 43a having a substantially cylindrical shape and an outer protruding portion 43b protruding radially outward from the lower end of the tubular portion 43a.

[0085] The inner circumferential surface of the cylindrical portion 43a has an outer defining surface G2b of the second magnetic gap G2 and an inclined inner surface 43a1 that slopes downward and radially outward. The outer protrusion 43b has an abutment surface 43b1 that abuts against the second magnet. The inclined inner surface 43a1 is provided between the outer defining surface G1b and the abutment surface 43b1.

[0086] The first magnetic member 41 is disposed on the upper surface of the first magnet 42. The first magnetic member 41 has a substantially cylindrical shape. The outer peripheral surface of the first magnetic member 41 has an inner forming surface G1a of the first magnetic gap G1.

[0087] 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 an inner surface G1a of the first magnetic gap G1.

[0088] (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.

[0089] 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.

[0090] 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 27 a of the first elastic support portion 27 . The fourth bottom wall portion 54 supports the outer edge portion of the second elastic support portion 37 . The magnetic circuit support portion 55 supports the magnetic circuit 40 .

[0091] The first bottom wall portion 51, the second bottom wall portion 52, and the fourth bottom wall portion 54 support the 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.

[0092] The outer edge of the edge 25 is located radially outward of the outer edge of the first elastic support portion 27 . The outer edge of the first elastic support portion 27 is located radially outward of the outer edge of the second elastic support portion 37 . The outer edge of the second elastic support portion 37 is located radially outward of the attached portion 45d of the magnetic circuit 40.

[0093] 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 .

[0094] The first connecting portion 56 connects the first bottom wall portion 51 and the second bottom wall portion 52 together. The second connecting portion 57 connects the second bottom wall portion 52 and the third bottom wall portion 53 together. The third connecting portion 58 connects the third bottom wall portion 53 and the fourth bottom wall portion 54 together. The fourth connection portion 59 connects the fourth bottom wall portion 54 and the magnetic circuit support portion 55 together.

[0095] 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 inclined wall 57a that is inclined with respect to the axial direction. The third connecting portion 58 has a third inclined wall 58a that is 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.

[0096] The frame 50 is integrally molded (molded from resin). That is, the first bottom wall portion 51, the first connecting portion 56, the second bottom wall portion 52, the second connecting portion 57, the third bottom wall portion 53, the third connecting portion 58, the fourth bottom wall portion 54, the fourth connecting portion 59, and the magnetic circuit support portion 55 are integrally molded (molded from resin).

[0097] Next, the relationship between the magnetic circuit 40 and the first and second vibrating parts 20 and 30 will be described.

[0098] 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.

[0099] 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.

[0100] <Action and effect> Next, the effects of this embodiment will be described.

[0101] In this embodiment, as shown in FIG. 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 as to allow axial displacement. The second vibrating section 30 includes a second coil 32 having a diameter larger than that of 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 as to allow axial displacement. The magnetic circuit 40 includes a first magnetic gap G1 in which the first coil 22 is disposed, and a second magnetic gap G2 in which the second coil 32 is disposed. The first magnetic gap G1 is open to one axial side, and the second magnetic gap G2 is open to one axial side.

[0102] In this embodiment, as shown in FIG. 1, the magnetic circuit 40 includes a first magnet 42 and an annular second magnet 44, which are disposed radially inward of the first magnetic gap G1. Therefore, compared to a configuration in which the magnetic circuit 40 includes only one of the first magnet 42 and the second magnet 44, the magnetic flux density of the first magnetic gap G1 and the second magnetic gap G2 can be ensured.

[0103] In this embodiment, as shown in FIG. 1, the annular second magnet 44 is disposed radially outward of the second magnetic gap G2. For this reason, the second magnetic gap G2 is located radially inward of the inner circumferential surface of the annular second magnet 44. This makes it easier to reduce the diameter of the second coil 32 disposed in the second magnetic gap G2. If the diameter of the second coil 32 can be reduced, the diameter of the second bobbin 31 can also be reduced, making it possible to effectively utilize the space radially outward of the second bobbin 31. As a result, it is easier to reduce the size of the speaker 10.

[0104] In this embodiment, as shown in FIG. 3, the magnetic circuit 40 includes a common magnetic member 45 having a cylindrical wall portion 45b extending in the axial direction. Here, the radially inner surface of the cylindrical wall portion 45b has an outer forming surface G1b that forms the first magnetic gap G1, and the radially outer surface of the cylindrical wall portion 45b has an inner forming surface G2a that forms the second magnetic gap G2. Therefore, the cylindrical wall portion 45b of the common magnetic member 45 can be used in common by the magnetic circuit for the first magnetic gap G1 and the magnetic circuit for the second magnetic gap G2.

[0105] In this embodiment, the common magnetic member 45 includes an outer bottom wall portion 45e that protrudes radially outward from the cylindrical wall portion 45b. The second magnet 44 is disposed on one axial side of the outer bottom wall portion 45e. Therefore, compared to a configuration in which the outer bottom wall portion 45e on which the second magnet 44 is disposed on one axial side is formed as a separate body from the common magnetic member 45, the number of parts can be reduced.

[0106] In this embodiment, the magnetic circuit 40 includes an annular magnetic member 43. The annular magnetic member 43 has an outer forming surface G2b that forms the second magnetic gap G2, and an abutment surface 43b1 that abuts against the second magnet 44. Here, the radially inner end of the contact surface 43b1 is located radially outward of the outer defining surface G2b of the second magnetic gap G2. Therefore, interference between the second coil 32 and the annular magnetic member 43 can be suppressed.

[0107] In this embodiment, as shown in FIG. 2, the second elastic support portion 37 includes a one-side elastic body 38a and an other-side elastic body 38b. Therefore, the second vibrating part 30 can be vibrated in a stable posture.

[0108] Incidentally, in the case where the second elastic support portion 37 includes the one-side elastic body 38a and the other-side elastic body 38b, when the one-side elastic body 38a and the other-side elastic body 38b are each joined to the second bobbin 31, it is necessary to form the portion of the second bobbin 31 that is arranged outside the magnetic circuit 40 long in the axial direction. This leads to an increase in the size of the second vibrating portion 30 in the axial direction, and therefore an increase in the size of the entire speaker 10. Therefore, in this embodiment, the second vibrating section 30 includes a second coupler 39 that connects the second bobbin 31 and the one-side elastic body 38a and also connects the second bobbin 31 and the other-side elastic body 38b. Therefore, the one-side elastic body 38a and the other-side elastic body 38b are connected to the second bobbin 31 via the second coupler 39. Therefore, it is not necessary to form the portion of the second bobbin 31 that is disposed outside the magnetic circuit 40 long in the axial direction. This makes it easy to make the speaker 10 smaller in size in the axial direction.

[0109] In this embodiment, as shown in FIG. 2, in the inoperative state, the entire other-side elastic body 38b is located on the other axial side of the one axial end of the second coil 32. Therefore, the space radially outward from the magnetic circuit 40 and on the other axial side of the one axial end of the second magnetic gap G2 can be effectively used as a space in which the other-side elastic body 38b is disposed.

[0110] In addition, in this embodiment, an air vent (not shown) is formed in the second coupler 39 between the connection position of the one side elastic body 38a (one side joint 39c) and the connection position of the other side elastic body 38b (other side joint 39f). Therefore, the influence of the back pressure received when the second vibrating part 30 vibrates can be reduced.

[0111] In this embodiment, the first elastic support portion 27 has recesses 29c, 29d, and 29e for avoiding interference with the second bobbin 31, as shown in FIG. This allows the first vibrating portion 20 and the second vibrating portion 30 to be closer to each other in the axial direction, which makes it easier to reduce the size of the speaker 10 in the axial direction.

[0112] In this embodiment, the first elastic support member 27 includes an elastic body 27a and a first coupler 29 that connects the elastic body 27a to the first bobbin 21. The first coupler 29 has recesses 29c, 29d, and 29e for avoiding interference with the second bobbin 31. Therefore, compared to a mode in which the elastic body 27a has recesses, the recesses 29c, 29d, and 29e can be formed to be less likely to deform.

[0113] In this embodiment, although not shown, the recesses 29c, 29d, and 29e are configured so that at least a part of the second coupler 39 (first connecting portion 39b) can enter (see FIG. 2). This allows the first vibrating portion 20 and the second vibrating portion 30 to be brought even closer together in the axial direction, making it easier to reduce the size of the speaker 10 in the axial direction.

[0114] 1, the first vibrating section 20 includes a diaphragm 24. The diaphragm 24 is connected to the first bobbin 21 without a first coupler 29 therebetween. Therefore, compared to a configuration in which diaphragm 24 is connected to first bobbin 21 via first coupler 29, the vibration of first bobbin 21 can be transmitted more directly to diaphragm 24. In other words, audio signals can be transmitted to diaphragm 24 with less loss.

[0115] In this embodiment, as shown in FIG. 3, the magnetization direction of the first magnet 42 and the magnetization direction of the second magnet 44 are both axially aligned and opposite to each other. This makes it easy to ensure the magnetic flux density in the first magnetic gap G1 and the second magnetic gap G2.

[0116] 3, the axial range in which the second magnetic gap G2 is located falls within the axial range in which the first magnetic gap G1 and the space 49 below the first magnetic gap G1 are located. The space 49 below the first magnetic gap G1 is configured to allow the first coil 22 to enter. Therefore, it is easier to reduce the size of the speaker 10 in the axial direction compared to a configuration in which the axial range in which the second magnetic gap G2 is located does not fall within the axial range in which the first magnetic gap G1 and space 49 are located.

[0117] In this embodiment, as shown in FIG. 3, the radially outer surface of the outer protrusion 43b of the second magnetic member 43 (annular magnetic member 43) is located radially inward of the outer peripheral surface of the second magnet 44. Therefore, interference between the second coupler 39 and the magnetic circuit 40 is less likely to occur, and the second elastic support portion 37 can be easily set at a low position.

[0118] In addition, in this embodiment, as shown in FIG. 1, the first vibrating unit 20 is a driving unit for producing sound, and the second vibrating unit 30 is a driving unit for canceling out the vibration of the entire speaker 10 caused by the first vibrating unit 20. Therefore, vibration of the entire speaker 10 can be suppressed.

[0119] 〔supplementary explanation〕 Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments.

[0120] In the above embodiment, the upper surface of the bottom wall portion 45a of the third magnetic member 45 and the upper surface of the outer bottom wall portion 45e are aligned in the axial direction as shown in Fig. 3. However, the present disclosure is not limited to this. For example, the upper surface of the outer bottom wall portion 45e may be located higher than the upper surface of the bottom wall portion 45a. Furthermore, for example, the portion of the upper surface of the outer bottom wall portion 45e where the second magnet 44 is arranged may be located higher than the upper surface of the bottom wall portion 45a. In this case, the portion of the upper surface of the outer bottom wall portion 45e that is radially inward of the portion where the second magnet 44 is arranged may be aligned in the axial direction with the upper surface of the bottom wall portion 45a.

[0121] In the above embodiment, the one-side elastic body 38a is made of cloth, and the other-side elastic body 38b is made of rubber. However, the present disclosure is not limited to this. The one-side elastic body 38a may be made of rubber, and the other-side elastic body 38b may be made of cloth. By forming one of the one-side elastic body 38a and the other-side elastic body 38b from rubber, it is possible to suppress sagging of the second support portion as a whole, compared to, for example, an embodiment in which both the one-side elastic body and the other-side elastic body are made of cloth. Furthermore, the present disclosure is not limited to the above, and the one-side elastic body 38a and the other-side elastic body 38b may both be made of cloth, or may both be made of rubber.

[0122] In the above embodiment, the first elastic support portion 27 includes the first coupler 29. However, the present disclosure is not limited to this, and the first elastic support portion 27 may be configured with only at least one elastic body. [Explanation of symbols]

[0123] 10 Speakers 20 First vibration section 21 First bobbin 22 First coil 24 Diaphragm 27 First elastic support part 29 First Coupler 29c,29d,29e depression 30 Second vibration section 31 Second bobbin 32 Second coil 37 Second elastic support part 38a One-side elastic body 38b Other side elastic body 39 Second Coupler 40 Magnetic Circuit 41 First magnetic member 42 First magnet 43 Second magnetic member (annular magnetic member) 43b1 Contact surface 44 Second magnet 45 Third magnetic member (common magnetic member) 45b Cylinder wall 45e Outer bottom wall 50 frames 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 first vibration portion; A second vibration part; A magnetic circuit; a frame supporting the first vibration part, the second vibration part, and the magnetic circuit; A speaker comprising: The first vibration portion is A first coil; a first bobbin on which the first coil is provided; a first elastic support portion that elastically supports the first bobbin so that the first bobbin is displaceable in the axial direction; Equipped with The second vibration portion is a second coil having a diameter larger than that of the first coil; a second bobbin on which the second coil is provided; a second elastic support portion that elastically supports the second bobbin so that the second bobbin is displaceable in the axial direction; Equipped with The magnetic circuit comprises: a first magnetic gap in which the first coil is disposed; a second magnetic gap in which the second coil is disposed; Equipped with The first magnetic gap is open to an upper side, which is one axial side, The second magnetic gap is open to an upper side, which is one axial side, The magnetic circuit comprises: a first magnet disposed radially inward of the first magnetic gap; an annular second magnet disposed radially outward of the second magnetic gap; Equipped with Speaker.

2. The magnetic circuit comprises: a common magnetic member having a cylindrical wall portion extending in an axial direction; a radially inner surface of the cylindrical wall portion having an outer forming surface that forms the first magnetic gap; a radially outer surface of the cylindrical wall portion having an inner forming surface that forms the second magnetic gap; 2. The speaker according to claim 1.

3. The shared magnetic member is an outer bottom wall portion that projects radially outward from the cylindrical wall portion; Equipped with The second magnet is disposed on one axial side of the outer bottom wall portion.

3. The speaker according to claim 2.

4. The magnetic circuit comprises: Annular magnetic member Equipped with The annular magnetic member is an outer forming surface that forms the second magnetic gap; a contact surface that contacts the second magnet; and a radially inner end of the abutment surface is located radially outward of an outer defining surface of the second magnetic gap; 2. The speaker according to claim 1.

5. The second elastic support portion is One elastic body; a second elastic body provided on the other axial side of the first elastic body; a second coupler that connects the second bobbin and the one-side elastic body and also connects the second bobbin and the other-side elastic body; Equipped with 2. The speaker according to claim 1.

6. At least a portion of the other-side elastic body is located on the other axial side of the one axial end of the second coil.

6. The speaker according to claim 5.

7. an air hole is formed in the second coupler between a connection position of the one-side elastic body and a connection position of the other-side elastic body; 6. The speaker according to claim 5.

8. The first elastic support portion has a recess for avoiding interference with the second bobbin.

2. The speaker according to claim 1.

9. The first elastic support portion is An elastic body; a first coupler that connects the elastic body and the first bobbin; Equipped with the first coupler has a recess for avoiding interference with the second bobbin; 2. The speaker according to claim 1.

10. the first vibration portion includes a vibration plate, the diaphragm is connected to the first bobbin without the first coupler; 10. The speaker according to claim 9.

11. The magnetization direction of the first magnet and the magnetization direction of the second magnet are both axially aligned and opposite to each other.

2. The speaker according to claim 1.

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