Speaker

Abstract

A speaker (2) is provided with: a diaphragm (38) formed in an annular shape; an artillery shell-shaped first equalizer (12) disposed on the radially inner side of the diaphragm (38); an annular second equalizer (14) disposed on the radially outer side of the diaphragm (38); and a diaphragm (62) disposed on the radially outer side of the second equalizer (14) and extending from an inclined surface (56) of the second equalizer (14) while expanding in a cone shape. In a cross section including the center axis line (18), a first virtual line (78) defined by a portion of the ridge line of the first equalizer (12) on one side with respect to the center axis line (18), and a second virtual line (80) defined by portions of the ridge lines of the second equalizer (14) and the diaphragm (62) on one side with respect to the center axis line (18) are arranged substantially symmetrically with respect to a predetermined axis line (82).

Description

Speaker

[0001] The present disclosure relates to a speaker.

[0002] Patent Document 1 discloses a speaker for outputting sound, which includes a diaphragm formed in a circular ring shape, a bullet-shaped equalizer disposed radially inward of the diaphragm, an annular equalizer disposed radially outward of the diaphragm, and a plurality of connecting arms connecting the bullet-shaped equalizer and the annular equalizer.

[0003] Japanese Patent Application Laid-Open No. 2006-100879

[0004] The present disclosure provides a speaker that can improve acoustic characteristics.

[0005] A speaker according to the present disclosure comprises: a first diaphragm formed in an annular shape centered on a central axis; a first equalizer arranged radially inside the first diaphragm and formed in a bullet shape centered on the central axis; a second equalizer arranged radially outside the first diaphragm, the second equalizer formed in an annular shape centered on the central axis and having an inclined surface whose diameter increases with increasing distance from the first diaphragm; and a second diaphragm arranged radially outside the second equalizer and extending while expanding in a cone shape from the inclined surface of the second equalizer centered on the central axis, wherein, in a cross section including the central axis, a first imaginary line defined by a portion of the ridge line of the first equalizer on one side of the central axis, and a second imaginary line defined by a portion of the ridge lines of the second equalizer and the second diaphragm on the one side of the central axis are arranged substantially symmetrically with respect to a predetermined axis.

[0006] The speaker according to the present disclosure can improve acoustic characteristics.

[0007] Fig. 1 is a perspective view showing the appearance of a speaker according to an embodiment. Fig. 2 is a cross-sectional perspective view of the speaker according to the embodiment taken along line II-II in Fig. 1. Fig. 3 is a cross-sectional view of the speaker according to the embodiment taken along line III-III in Fig. 1. Fig. 4 is a cross-sectional view showing an enlarged view of a portion of the speaker of Fig. 3. Fig. 5 is a cross-sectional view showing an enlarged view of the diaphragm of a tweeter unit of a speaker according to an embodiment. Fig. 6 is a cross-sectional view showing an enlarged view of the diaphragm of a tweeter unit of a speaker according to a modified example.

[0008] (Findings that Form the Basis of the Present Disclosure) The present inventors have found that the following problems arise with the techniques described in the "Background Art" section.

[0009] The speaker disclosed in the above-mentioned Patent Document 1 may be applied to a coaxial speaker in which a tweeter unit and a woofer unit are arranged coaxially. In this case, the speaker includes a tweeter diaphragm formed in an annular shape, a bullet-shaped equalizer arranged radially inside the tweeter diaphragm, an annular equalizer arranged radially outside the tweeter diaphragm, a plurality of connecting arms connecting the bullet-shaped equalizer and the annular equalizer, and a woofer diaphragm arranged radially outside the annular equalizer and expanding in a cone shape.

[0010] However, in such a speaker configuration, when high-frequency sounds are output from the tweeter diaphragm, the woofer diaphragm acts as a baffle, so the shape of the woofer diaphragm has a significant effect on the acoustic characteristics of the high-frequency sounds, resulting in problems such as a narrower directivity and a deterioration in sound quality, which can degrade the acoustic characteristics of the speaker.

[0011] Therefore, the present inventors have conducted extensive research and have come up with a speaker that can improve acoustic characteristics.

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of well-known matters or redundant explanation of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0013] The inventors provide the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims.

[0014] (Embodiment) Hereinafter, an embodiment will be described with reference to FIGS.

[0015] [1. Speaker Configuration] First, the configuration of a speaker 2 according to an embodiment will be described with reference to Figs. 1 to 5. Fig. 1 is a perspective view showing the appearance of the speaker 2 according to an embodiment. Fig. 2 is a cross-sectional perspective view of the speaker 2 according to an embodiment taken along line II-II in Fig. 1. Fig. 3 is a cross-sectional view of the speaker 2 according to an embodiment taken along line III-III in Fig. 1. Fig. 4 is a cross-sectional view showing an enlarged portion of the speaker 2 in Fig. 3. Fig. 5 is a cross-sectional view showing an enlarged diaphragm 38 of the tweeter unit 10 of the speaker 2 according to an embodiment.

[0016] 1 to 5, the left-right direction of the speaker 2 is the X-axis direction, the up-down direction of the speaker 2 is the Y-axis direction, and the front-to-back direction of the speaker 2 is the Z-axis direction. The positive side of the X-axis is the "right," the negative side of the X-axis is the "left," the positive side of the Y-axis is the "up," the negative side of the Y-axis is the "down," the positive side of the Z-axis is the "front," and the negative side of the Z-axis is the "rear."

[0017] As shown in Figures 1 to 4, the speaker 2 includes a first frame 4, a woofer magnetic circuit 6, a tweeter magnetic circuit 8, a tweeter unit 10, a first equalizer 12, a second equalizer 14, and a woofer unit 16.

[0018] In this embodiment, the speaker 2 is a so-called coaxial speaker in which the tweeter unit 10 and the woofer unit 16 are arranged on the same central axis 18 (coaxially). Here, the central axis 18 is an imaginary straight line that passes through the radial center of the speaker 2 and extends along the front-to-rear direction (Z-axis direction). Also, Figures 2 to 5 show a cross section of the speaker 2 taken along a cutting plane that includes the central axis 18 (hereinafter simply referred to as "cross section including the central axis 18"). Although not shown, the back of the speaker 2 is covered by a box-shaped cabinet (enclosure).

[0019] The first frame 4 is disposed inside the cabinet and serves to support the woofer unit 16. The first frame 4 is made of, for example, resin or metal.

[0020] The woofer magnetic circuit 6 is disposed inside the cabinet and is arranged to support the first frame 4 from the rear (negative side of the Z axis). The woofer magnetic circuit 6 includes a bottom plate 20, a top plate 22, and a magnet 24. The bottom plate 20 is formed, for example, from iron and has a cylindrical portion 20a and a flange portion 20b that protrudes radially outward from the rear end of the cylindrical portion 20a (the end farther from the tweeter unit 10). Note that, in this specification, "radial direction" refers to a direction perpendicular to the central axis 18. The flange portion 20b of the bottom plate 20 supports the magnet 24 from the rear. The top plate 22 is formed, for example, from iron and has an annular shape and is arranged to cover the magnet 24 from the front (positive side of the Z axis). The top plate 22 also supports the first frame 4 from the rear. The magnet 24 is an annular magnet, and is sandwiched between the flange portion 20b of the bottom plate 20 and the top plate 22 in the front-rear direction.

[0021] The tweeter magnetic circuit 8 is disposed inside a voice coil bobbin 64 (described later) of the woofer unit 16 and includes a yoke 26, a top plate 28, and a magnet 30. The yoke 26 is formed, for example, from iron and includes a cylindrical portion 26a and a flange portion 26b that protrudes radially inward from the rear end of the cylindrical portion 26a (the end farther from the second equalizer 14). The flange portion 26b of the yoke 26 supports the magnet 30 from the rear. The yoke 26 and the cylindrical portion 20a of the bottom plate 20 of the woofer magnetic circuit 6 are fixed to each other via a supporter 32 made of resin. A second frame 34 (an example of a support member) formed in an annular shape is fixed to the outer periphery of the cylindrical portion 26a of the yoke 26. The top plate 28 is formed, for example, from iron and is disposed to cover the magnet 30 from the front. A pillar-shaped support column 36 (an example of a support member) is fixed to the front surface (the surface opposite to the yoke 26) of the top plate 28. The magnet 30 is a disk-shaped magnet, and is sandwiched between the flange portion 26b of the yoke 26 and the top plate 28 in the front-rear direction.

[0022] The tweeter unit 10 is an acoustic unit for reproducing high-frequency sounds higher than those of the woofer unit 16, and is disposed inside the voice coil bobbin 64 of the woofer unit 16. The tweeter unit 10 includes the tweeter magnetic circuit 8 described above, a diaphragm 38 (an example of a first diaphragm), a voice coil bobbin 40, and a voice coil 42. Note that the high-frequency sounds reproduced by the tweeter unit 10 and the low-frequency sounds reproduced by the woofer unit 16 may overlap in some frequency bands.

[0023] The diaphragm 38 is formed in an annular shape centered on the central axis 18, and is supported by the second frame 34 and the support columns 36 so as to be able to vibrate in the front-to-rear direction (Z-axis direction). As shown in Fig. 5, the diaphragm 38 has, from the inner periphery to the outer periphery, an inner periphery support piece 48, an inner periphery edge 46, a vibrating portion 44, an outer periphery edge 50, and an outer periphery support piece 52, in this order.

[0024] In this embodiment, the vibrating portion 44, inner peripheral edge 46, and outer peripheral edge 50 are configured as separate bodies. That is, the outer peripheral portion of the inner peripheral edge 46 and the inner peripheral portion of the vibrating portion 44 overlap at an overlapping portion 45, and this overlapping portion 45 is bonded together, for example, with an adhesive. Also, the inner peripheral portion of the outer peripheral edge 50 and the outer peripheral portion of the vibrating portion 44 overlap at an overlapping portion 47, and this overlapping portion 47 is bonded together, for example, with an adhesive.

[0025] In this embodiment, the vibrating portion 44, the inner peripheral edge 46, and the outer peripheral edge 50 are configured as separate bodies, but this is not limiting and they may be formed as a single unit. Also, the overlapping portions 45 and 47 described above may be omitted, and the outer peripheral edge of the inner peripheral edge 46 (i.e., the periphery of the outer peripheral portion) and the inner peripheral edge of the vibrating portion 44 (i.e., the periphery of the inner peripheral portion) may be connected to each other with, for example, adhesive tape, and the inner peripheral edge of the outer peripheral edge 50 and the outer peripheral edge of the vibrating portion 44 may be connected to each other with, for example, adhesive tape.

[0026] Furthermore, in this embodiment, the vibration plate 38 is supported by the second frame 34 and the support pillar 36 so as to be able to vibrate in the front-to-rear direction, but this is not limited to this, and the vibration plate 38 may also be supported by the first frame 4 (an example of a support member) so as to be able to vibrate in the front-to-rear direction.

[0027] The vibration portion 44 is formed in an annular shape centered on the central axis 18 and curved convexly backward (an example of a first direction).

[0028] The inner peripheral edge 46 is formed in an annular shape centered on the central axis 18 and is curved forward (an example of a second direction, which is the opposite direction to the first direction) in a convex shape. That is, the inner peripheral edge 46 is a roll edge having a substantially arc-shaped cross section and is made of, for example, rubber. The outer periphery of the inner peripheral edge 46 is connected to the inner periphery of the vibrating part 44 at the overlapping portion 45 described above.

[0029] The inner peripheral support piece 48 protrudes inward in the radial direction from the inner peripheral edge of the inner peripheral edge 46 in an annular shape, and is supported between the support pillar 36 and the first equalizer 12. As a result, the inner peripheral edge 46 is interposed between the inner peripheral portion of the vibrating part 44 and the support pillar 36.

[0030] The outer peripheral edge 50 is formed in an annular shape centered on the central axis 18 and curves forward in a convex manner. That is, the outer peripheral edge 50 is a roll edge having a substantially arc-shaped cross section and is made of, for example, rubber. The inner peripheral portion of the outer peripheral edge 50 is connected to the outer peripheral portion of the vibrating portion 44 at an overlapping portion 47.

[0031] The outer peripheral support piece 52 protrudes radially outward from the outer periphery of the outer peripheral edge 50 in an annular shape, and is supported between the second frame 34 and the second equalizer 14. As a result, the outer peripheral edge 50 is interposed between the outer periphery of the vibrating part 44 and the second frame 34.

[0032] 5, in a cross section including the center axis 18, the width W1 of the outer peripheral edge 50 in the radial direction (the X-axis direction in FIG. 5) is greater than the width W2 of the inner peripheral edge 46 in the radial direction (the X-axis direction in FIG. 5). Note that the width W1 is the radial width of the portion of the outer peripheral edge 50 that does not include the overlapping portion 47. The width W2 is the radial width of the portion of the inner peripheral edge 46 that does not include the overlapping portion 45.

[0033] The voice coil bobbin 40 is connected to the convex side of the vibrating portion 44 of the diaphragm 38 and extends cylindrically rearward from the vibrating portion 44 .

[0034] The voice coil 42 is wound around the outer peripheral surface of the voice coil bobbin 40 and is disposed in the magnetic gap formed between the cylindrical portion 26a of the yoke 26 and the top plate 28. In other words, the voice coil 42 is connected to the vibrating portion 44 via the voice coil bobbin 40.

[0035] A magnetic field is generated in the magnetic gap in which the voice coil 42 is disposed by the magnetic force from the magnet 30. When a current flows through the voice coil 42, the voice coil 42 receives a force from the magnetic field in the magnetic gap and vibrates. When the vibration of the voice coil 42 is transmitted to the voice coil bobbin 40, the diaphragm 38 connected to the voice coil bobbin 40 vibrates in the front-to-rear direction, and sound waves mainly in the high-pitched range are generated from the diaphragm 38.

[0036] The first equalizer 12 is a bullet-shaped equalizer for improving acoustic characteristics such as frequency response and directional characteristics of the tweeter unit 10. The first equalizer 12 is disposed radially inward of the diaphragm 38 of the tweeter unit 10 and supported by the support column 36 so as to cover it. The first equalizer 12 is formed in a bullet shape centered on the central axis 18. More specifically, the first equalizer 12 is formed so as to taper from the base end (i.e., the end closer to the diaphragm 38) to the tip end (i.e., the end farther from the diaphragm 38), and the outer peripheral surface 54 of the first equalizer 12 is curved convexly radially outward. Furthermore, the outer peripheral edge of the base end of the first equalizer 12 is located radially outward of the front end of the inner peripheral edge 46, which protrudes furthest forward. That is, when viewed from the front-rear direction (Z-axis direction), the first equalizer 12 and the front end of the inner peripheral edge 46 overlap each other.

[0037] The second equalizer 14 is an annular equalizer for improving acoustic characteristics such as frequency response and directional characteristics of the tweeter unit 10. The second equalizer 14 is disposed radially outward of the diaphragm 38 of the tweeter unit 10 and is supported by the front end (the end closer to the second equalizer 14) of the supporter 32. The second equalizer 14 is formed in an annular shape centered on the central axis 18. More specifically, the second equalizer 14 has an inclined surface 56 that increases in diameter with increasing distance from the diaphragm 38 and that curves convexly radially inward. That is, the diameter of an opening 58 at the rear end (i.e., the end closer to the diaphragm 38) of the second equalizer 14 is smaller than the diameter of an opening 60 at the front end (i.e., the end farther from the diaphragm 38) of the second equalizer 14. The opening 58 of the second equalizer 14 is located near the convex side of the outer peripheral edge 50 of the diaphragm 38 of the tweeter unit 10. Specifically, the opening 58 of the second equalizer 14 is located more inward than the front end of the outer peripheral edge 50 that protrudes furthest forward. That is, when viewed from the front-to-rear direction (Z-axis direction), the second equalizer 14 and the front end of the outer peripheral edge 50 overlap. The opening 60 of the second equalizer 14 is located near the front end (the end closer to the tweeter unit 10) of the voice coil bobbin 64 of the woofer unit 16. Note that the tip of the first equalizer 12 protrudes further forward than the opening 60 of the second equalizer 14.

[0038] The woofer unit 16 is an acoustic unit for reproducing bass frequencies lower than those of the tweeter unit 10, and includes the above-mentioned woofer magnetic circuit 6, a diaphragm 62 (an example of a second diaphragm), a voice coil bobbin 64, a damper 66, and a voice coil 68.

[0039] The diaphragm 62 has a cone-like (frustum-like) shape that widens in diameter toward the front, centered on the central axis 18. That is, the diameter of an opening 70 at the rear end of the diaphragm 62 (i.e., the end closer to the tweeter unit 10) is smaller than the diameter of an opening 72 at the front end of the diaphragm 62 (i.e., the end farther from the tweeter unit 10). The opening 70 of the diaphragm 62 is supported by the front end of the voice coil bobbin 64. As a result, the diaphragm 62 extends from the inclined surface 56 of the second equalizer 14 while widening in a cone-like shape. Furthermore, the opening 72 of the diaphragm 62 is supported by the peripheral edge of the opening 76 of the first frame 4 via an edge 74 made of, for example, rubber, so as to be vibrable in the front-rear direction. That is, the opening 70, opening 72, and edge 74 of the diaphragm 62 are arranged in this order from the inner periphery toward the outer periphery.

[0040] The diaphragm 38 of the tweeter unit 10 is disposed at the radial center of the diaphragm 62. That is, the diaphragm 62 of the woofer unit 16 and the diaphragm 38 of the tweeter unit 10 are disposed on the same central axis 18.

[0041] The voice coil bobbin 64 is connected to an opening 70 in the diaphragm 62 and extends cylindrically rearward from the opening 70 in the diaphragm 62. The voice coil bobbin 64 is also disposed so as to face the outer circumferential surface of the second equalizer 14, the outer circumferential surface of the supporter 32, and part of the outer circumferential surface of the cylindrical portion 20a of the bottom plate 20 of the woofer magnetic circuit 6, and is supported by the first frame 4 via a damper 66 so as to be vibrable in the front-rear direction.

[0042] The voice coil 68 is wound around the outer peripheral surface of the voice coil bobbin 64 and is disposed in the magnetic gap formed between the cylindrical portion 20 a of the bottom plate 20 and the top plate 22 of the woofer magnetic circuit 6 .

[0043] A magnetic field is generated in the magnetic gap in which the voice coil 68 is disposed by the magnetic force from the magnet 24. When a current flows through the voice coil 68, the voice coil 68 receives a force from the magnetic field in the magnetic gap and vibrates. When the vibration of the voice coil 68 is transmitted to the voice coil bobbin 64, the diaphragm 62 connected to the voice coil bobbin 64 vibrates in the front-to-rear direction, and sound waves mainly in the low-frequency range are generated from the diaphragm 62.

[0044] 4 , in a cross section including the central axis 18, a first imaginary line 78 (shown by a thick line in FIG. 4 ) and a second imaginary line 80 (shown by a thick line in FIG. 4 ) are disposed substantially symmetrically with respect to a predetermined axis 82. The first imaginary line 78 is a curve defined by a portion of the ridgeline of the first equalizer 12 (i.e., the outer peripheral surface 54 of the first equalizer 12) on one side of the central axis 18 (to the right of the central axis 18 in FIG. 4 ). The second imaginary line 80 is a curve defined by a portion of the ridgeline of the second equalizer 14 (i.e., the inclined surface 56 of the second equalizer 14) on one side of the central axis 18 and a portion of the ridgeline of the diaphragm 62 (i.e., the surface of the diaphragm 62) on one side of the central axis 18. In this embodiment, the second virtual line 80 is only a curved line, but this is not limited thereto and may be a virtual line in which a curved line and a straight line are continuously connected. The predetermined axis 82 is an axis of line symmetry between the first virtual line 78 and the second virtual line 80, and is a virtual straight line extending at an angle relative to the central axis 18. In this specification, "substantially line symmetric" refers not only to strict line symmetry but also to cases that are not strictly line symmetric but are recognized as line symmetry by those skilled in the art. In this embodiment, the predetermined axis 82 extends at an angle relative to the central axis 18, but this is not limited thereto and may extend parallel to the central axis 18.

[0045] [2. Effects] In the present embodiment, as described above, in a cross section including the central axis 18, the first virtual line 78 and the second virtual line 80 are disposed substantially symmetrically with respect to the predetermined axis 82. That is, the shapes of the outer peripheral surface 54 of the first equalizer 12 and the inclined surface 56 of the second equalizer 14 are formed so that the first virtual line 78 and the second virtual line 80 satisfy this positional relationship.

[0046] This allows the inclined surface 56 of the second equalizer 14 and the surface of the diaphragm 62 of the woofer unit 16 to be smoothly connected. In this specification, "smoothly connected" means that the normals of the surfaces of two adjacent members at the boundary between the two members are generally the same, and includes not only cases where the surfaces of the two adjacent members are physically connected, but also cases where the surfaces of the two adjacent members are not physically connected (i.e., there is a gap between the two adjacent members). As a result, the wavefronts of sound components of the high-frequency sound output from the diaphragm 38 of the tweeter unit 10 that travel along the inclined surface 56 of the second equalizer 14 and the surface of the diaphragm 62 of the woofer unit 16 can be prevented from being disrupted at the boundary between the inclined surface 56 of the second equalizer 14 and the diaphragm 62 of the woofer unit 16, thereby improving the acoustic characteristics of the speaker 2.

[0047] 2 to 4, a portion of the diaphragm 38 of the tweeter unit 10, the inclined surface 56 of the second equalizer 14, the surface of the diaphragm 62 of the woofer unit 16, and the surface of the edge 74 are arranged so as to be smoothly connected. Here, "a portion of the diaphragm 38" refers to a portion of the diaphragm 38 that is closer to the outer periphery than the connection portion with the voice coil bobbin 40 and that is not hidden by the second equalizer 14 when viewed from the positive side of the Z axis. Alternatively, "a portion of the diaphragm 38" refers to the overlapping portion 47 of the diaphragm 38 and its vicinity, as shown in FIG. 5. This configuration can suppress wavefront disturbances of the sound (air vibrations) output from the diaphragm 38 of the tweeter unit 10 as it travels along the portion of the diaphragm 38 of the tweeter unit 10, the inclined surface 56 of the second equalizer 14, the surface of the diaphragm 62 of the woofer unit 16, and the surface of the edge 74. As a result, deterioration of the frequency characteristics of the sound output from the diaphragm 38 of the tweeter unit 10 can be suppressed.

[0048] Furthermore, the back of the speaker 2 having such a configuration is covered with a cabinet (not shown), the gap between the edge 74 and the cabinet is filled with a rubber ring or the like (not shown), and the surfaces of the edge 74, the rubber ring or the like, and the cabinet are configured to be smoothly connected. With this configuration, it is possible to suppress wavefront disturbance of the sound (air vibrations) output from the diaphragm 38 of the tweeter unit 10 as it travels along the surface of the edge 74, the surface of the rubber ring or the like, and the surface of the cabinet. As a result, it is possible to suppress deterioration of the frequency characteristics of the sound output from the diaphragm 38 of the tweeter unit 10.

[0049] Furthermore, since the first virtual line 78 and the second virtual line 80 are arranged approximately symmetrically with respect to the predetermined axis 82, sound with suppressed wavefront disturbance can be output in directions along each of the first virtual line 78 and the second virtual line 80, and in the intended direction along the predetermined axis 82.

[0050] Furthermore, in the present embodiment, as described above, in a cross section including the central axis 18, the radial width W1 of the outer peripheral edge 50 is greater than the radial width W2 of the inner peripheral edge 46. This allows the effective diaphragm area of ​​the diaphragm 38 to be larger than when the radial width W1 of the outer peripheral edge 50 is equal to or smaller than the radial width W2 of the inner peripheral edge 46. As a result, the sound pressure of high-frequency sounds output from the diaphragm 38 can be increased while ensuring symmetry when the diaphragm 38 vibrates in the front-to-rear direction.

[0051] [3. Modification] Next, the configuration of a speaker 2A according to a modification will be described with reference to Fig. 6. Fig. 6 is an enlarged cross-sectional view of the diaphragm 38A of the tweeter unit 10A of the speaker 2A according to the modification. Note that in this modification, the same components as those of the speaker 2 shown in Figs. 1 to 5 are designated by the same reference numerals, and their description will be omitted.

[0052] As shown in Figure 6, in a speaker 2A according to this modification, the configuration of the diaphragm 38A of the tweeter unit 10A is different from that of the speaker 2 shown in Figures 1 to 5. Specifically, the diaphragm 38A has, from the inner periphery to the outer periphery, an inner periphery support piece 88, a second curved portion 86, a first curved portion 84, a third curved portion 90, and an outer periphery support piece 92, in this order. In this modification, the first curved portion 84, the second curved portion 86, and the third curved portion 90 are integrally configured.

[0053] The first curved portion 84 corresponds to the above-described vibrating portion 44. That is, the first curved portion 84 is formed in an annular shape centered on the central axis 18, and is curved convexly backward (an example of the first direction).

[0054] The second curved portion 86 corresponds to the inner peripheral edge 46. That is, the second curved portion 86 is formed in an annular shape centered on the central axis 18 and is curved convexly forward (an example of a second direction that is the opposite direction to the first direction).

[0055] The inner peripheral support piece 88 corresponds to the above-described inner peripheral support piece 48. That is, the inner peripheral support piece 88 protrudes in an annular shape radially inward from the inner peripheral edge of the second curved portion 86, and is supported between the support column 36 and the first equalizer 12.

[0056] The third curved portion 90 corresponds to the outer peripheral edge 50. That is, the third curved portion 90 is formed in an annular shape centered on the central axis 18 and curved forward in a convex shape.

[0057] The outer peripheral support piece 92 corresponds to the above-described outer peripheral support piece 52. That is, the outer peripheral support piece 92 protrudes in an annular shape radially outward from the outer peripheral edge of the third curved portion 90, and is supported between the second frame 34 and the second equalizer 14.

[0058] 6 , in a cross section including the central axis 18, when the boundary between the first curved portion 84 and the second curved portion 86 is defined as a first inflection point 94 and the boundary between the first curved portion 84 and the third curved portion 90 is defined as a second inflection point 96, the width W3 in the radial direction (X-axis direction) from the second inflection point 96 to the outer periphery of the third curved portion 90 is greater than the width W4 in the radial direction (X-axis direction) from the first inflection point 94 to the inner periphery of the second curved portion 86. Here, the first inflection point 94 is the boundary between the forward-convex portion (second curved portion 86) and the rearward-convex portion (first curved portion 84) of the diaphragm 38A. The second inflection point 96 is the boundary between the forward convex portion of the diaphragm 38A (the third curved portion 90) and the backward convex portion (the first curved portion 84).

[0059] As a result, in this modified example, similar to the above, the effective diaphragm area of ​​the diaphragm 38A can be made larger compared to when the width W3 in the radial direction from the second inflection point 96 to the outer peripheral edge of the third curved portion 90 is equal to or smaller than the width W4 in the radial direction from the first inflection point 94 to the inner peripheral edge of the second curved portion 86. As a result, the sound pressure of the high-pitched sound output from the diaphragm 38A can be made larger while ensuring symmetry when the diaphragm 38A vibrates in the front-to-rear direction.

[0060] (Additional Notes) (Technology 1) A speaker comprising: a first diaphragm formed in an annular shape centered on a central axis; a first equalizer arranged radially inward of the first diaphragm and formed in a bullet shape centered on the central axis; a second equalizer arranged radially outward of the first diaphragm, the second equalizer formed in an annular shape centered on the central axis and having an inclined surface that widens in diameter as it moves away from the first diaphragm; and a second diaphragm arranged radially outward of the second equalizer and extending while widening in a cone shape from the inclined surface of the second equalizer centered on the central axis, wherein, in a cross section including the central axis, a first imaginary line defined by a portion of the ridge line of the first equalizer on one side of the central axis and a second imaginary line defined by a portion of the ridge lines of the second equalizer and the second diaphragm on the one side of the central axis are arranged substantially symmetrically with respect to a predetermined axis.

[0061] According to Technology 1, in a cross section including the central axis, the first virtual line and the second virtual line are arranged substantially symmetrically with respect to a predetermined axis. This allows the inclined surface of the second equalizer and the surface of the second diaphragm to be smoothly connected. As a result, the wavefront of a sound component of the sound output from the first diaphragm that travels along the inclined surface of the second equalizer and the surface of the second diaphragm can be prevented from being disturbed at the boundary between the inclined surface of the second equalizer and the second diaphragm, thereby improving the acoustic characteristics of the speaker. Furthermore, because the first virtual line and the second virtual line are arranged substantially symmetrically with respect to the predetermined axis, sound with reduced wavefront disturbance can be output in directions along each of the first virtual line and the second virtual line, and in a direction along the predetermined axis, which is the intended direction.

[0062] (Technology 2) The speaker according to Technology 1, further comprising: a magnetic circuit; a voice coil disposed in a magnetic gap of the magnetic circuit; and a support member supporting the first diaphragm, wherein the first diaphragm has a vibrating portion formed in an annular shape around the central axis and connected to the voice coil; an inner peripheral edge formed in an annular shape around the central axis and interposed between an inner peripheral edge of the vibrating portion and the support member; and an outer peripheral edge formed in an annular shape around the central axis and interposed between an outer peripheral edge of the vibrating portion and the support member, wherein in the cross section including the central axis, a radial width of the outer peripheral edge is greater than a radial width of the inner peripheral edge.

[0063] According to Technology 2, in a cross section including the central axis, the radial width of the outer peripheral edge is greater than the radial width of the inner peripheral edge. This allows the effective diaphragm area of ​​the first diaphragm to be larger than when the radial width of the outer peripheral edge is equal to or smaller than the radial width of the inner peripheral edge. As a result, the sound pressure of the sound output from the first diaphragm can be increased while ensuring symmetry when the first diaphragm vibrates.

[0064] (Technology 3) The speaker further includes a magnetic circuit, a voice coil disposed in a magnetic gap of the magnetic circuit, and a support member supporting the first diaphragm, the first diaphragm including a first curved portion formed in an annular shape around the central axis, the first curved portion being connected to the voice coil and curved convexly in a first direction, a second curved portion formed in an annular shape around the central axis, the second curved portion being interposed between the first curved portion and the support member on a radially inner side of the first curved portion and curved convexly in a second direction opposite to the first direction, and a second curved portion formed in an annular shape around the central axis, the second curved portion being connected to the voice coil and curved convexly in a second direction opposite to the first direction. and a third curved portion formed in a convex shape in the second direction, the third curved portion being interposed between the first curved portion and the support member radially outward of the first curved portion, the third curved portion being curved in a convex shape in the second direction, wherein, in the cross section including the central axis, when a boundary point between the first curved portion and the second curved portion is defined as a first inflection point and a boundary point between the first curved portion and the third curved portion is defined as a second inflection point, a radial width from the second inflection point to an outer peripheral edge of the third curved portion is larger than a radial width from the first inflection point to an inner peripheral edge of the second curved portion.

[0065] According to Technology 3, in a cross section including the central axis, the radial width from the second inflection point to the outer peripheral edge of the third curved portion is greater than the radial width from the first inflection point to the inner peripheral edge of the second curved portion. This makes it possible to increase the effective diaphragm area of ​​the first diaphragm compared to a case where the radial width from the second inflection point to the outer peripheral edge of the third curved portion is equal to or smaller than the radial width from the first inflection point to the inner peripheral edge of the second curved portion. As a result, it is possible to increase the sound pressure of the sound output from the first diaphragm while ensuring symmetry when the first diaphragm vibrates.

[0066] (Technology 4) A speaker according to any one of Technologies 1 to 3, wherein the first diaphragm constitutes a tweeter unit for reproducing high frequencies, and the second diaphragm constitutes a woofer unit for reproducing low frequencies or a squawker unit for reproducing mid frequencies.

[0067] According to Technology 4, it is possible to suppress the wavefront of the sound component of the sound output from the first diaphragm of the tweeter unit, which travels along the inclined surface of the second equalizer and the surface of the second diaphragm of the woofer unit, from being disturbed at the boundary between the inclined surface of the second equalizer and the second diaphragm, thereby improving the acoustic characteristics of the speaker.

[0068] (Other Embodiments) As described above, the embodiments have been described as examples of the technology disclosed in this application. However, the technology in this disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, it is also possible to combine the components described in the above embodiments to create new embodiments.

[0069] Therefore, other embodiments will be exemplified below.

[0070] In the above embodiment, the speaker 2 (2A) is a coaxial speaker in which the tweeter unit 10 (10A) and the woofer unit 16 are arranged coaxially. However, this is not limited thereto. The speaker 2 (2A) may be a coaxial speaker in which the tweeter unit 10 (10A) and a squawker unit for reproducing midrange sounds lower than those of the tweeter unit 10 (10A) are arranged coaxially. In this case, the diaphragm 62 is used as a second diaphragm constituting the squawker unit. Note that the treble sounds reproduced by the tweeter unit 10 and the midrange sounds reproduced by the squawker unit may overlap in some frequency bands. Alternatively, the speaker 2 (2A) may be a coaxial speaker in which the woofer unit 16 and a squawker unit for reproducing midrange sounds higher than those of the woofer unit 16 are arranged coaxially. In this case, the low frequency range reproduced by the woofer unit 16 and the mid frequency range reproduced by the squawker unit may overlap in part of the frequency band.

[0071] Furthermore, the above-mentioned speaker 2 (2A) may be, for example, a bookshelf type, a floor type, or a type suspended from the ceiling.

[0072] As described above, the embodiments have been described as examples of the technology in the present disclosure, and for that purpose, the accompanying drawings and detailed description have been provided.

[0073] Therefore, the components shown in the accompanying drawings and detailed description may include not only essential components for solving the problem, but also components that are not essential for solving the problem in order to illustrate the above technology. Therefore, the fact that these non-essential components are shown in the accompanying drawings or detailed description should not be interpreted as immediately indicating that these non-essential components are essential.

[0074] Furthermore, since the above-described embodiments are intended to illustrate the technology of the present disclosure, various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

[0075] The speaker according to the present disclosure can be applied to, for example, a coaxial speaker.

[0076] 2, 2A Speaker 4 First frame 6 Woofer magnetic circuit 8 Tweeter magnetic circuit 10, 10A Tweeter unit 12 First equalizer 14 Second equalizer 16 Woofer unit 18 Central axis 20 Bottom plate 20a, 26a Cylindrical portion 20b, 26b Flange portion 22, 28 Top plate 24, 30 Magnet 26 Yoke 32 Supporter 34 Second frame 36 Support column 38, 38A, 62 Diaphragm 40, 64 Voice coil bobbin 42, 68 Voice coil 44 Vibrating portion 45, 47 Overlapping portion 46 Inner peripheral edge 48, 88 Inner peripheral support piece 50 Outer peripheral edge 52, 92 Outer peripheral support piece 54 Outer peripheral surface 56 Inclined surface 58, 60, 70, 72, 76 Opening 66 Damper 74 Edge 78 First imaginary line 80 Second imaginary line 82 Predetermined axis 84 First curved portion 86 Second curved portion 90 Third curved portion 94 First inflection point 96 Second inflection point

Claims

1. A speaker comprising: a first diaphragm formed in an annular shape centered on a central axis; a first equalizer arranged radially inside the first diaphragm and formed in a bullet shape centered on the central axis; a second equalizer arranged radially outside the first diaphragm, the second equalizer formed in an annular shape centered on the central axis and having an inclined surface that expands in diameter as it moves away from the first diaphragm; and a second diaphragm arranged radially outside the second equalizer and extending while expanding in a cone shape from the inclined surface of the second equalizer centered on the central axis, wherein in a cross section including the central axis, a first imaginary line defined by a portion of the ridgeline of the first equalizer on one side of the central axis and a second imaginary line defined by a portion of the ridgelines of the second equalizer and the second diaphragm on the one side of the central axis are arranged approximately symmetrically about a predetermined axis.

2. The speaker according to claim 1, further comprising: a magnetic circuit; a voice coil disposed in a magnetic gap of the magnetic circuit; and a support member supporting the first diaphragm, wherein the first diaphragm has: a vibrating section formed in an annular shape about the central axis and connected to the voice coil; an inner peripheral edge formed in an annular shape about the central axis and interposed between an inner peripheral edge of the vibrating section and the support member; and an outer peripheral edge formed in an annular shape about the central axis and interposed between an outer peripheral edge of the vibrating section and the support member, wherein in the cross section including the central axis, the radial width of the outer peripheral edge is greater than the radial width of the inner peripheral edge.

3. The speaker further comprises: a magnetic circuit; a voice coil disposed in a magnetic gap of the magnetic circuit; and a support member supporting the first diaphragm, wherein the first diaphragm has: a first curved portion formed in an annular shape about the central axis, the first curved portion being connected to the voice coil and curved convexly in a first direction; a second curved portion formed in an annular shape about the central axis, the second curved portion being interposed between the first curved portion and the support member on a radially inner side of the first curved portion and curved convexly in a second direction opposite to the first direction; and a third curved portion formed in an annular shape about the central axis, the third curved portion being interposed between the first curved portion and the support member on a radially outer side of the first curved portion and curved convexly in the second direction; 2. The speaker according to claim 1, wherein, in the cross section including the central axis, when a boundary point between the first curved portion and the second curved portion is defined as a first inflection point and a boundary point between the first curved portion and the third curved portion is defined as a second inflection point, a radial width from the second inflection point to an outer circumferential edge of the third curved portion is larger than a radial width from the first inflection point to an inner circumferential edge of the second curved portion.

4. A speaker as claimed in any one of claims 1 to 3, wherein the first diaphragm constitutes a tweeter unit for reproducing high-frequency sounds, and the second diaphragm constitutes a woofer unit for reproducing low-frequency sounds or a squawker unit for reproducing mid-frequency sounds.

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