Dome tweeters

Abstract

Dome loudspeaker comprising: a vibrating diaphragm (1) having a dome area (11) and a first connecting area (12) and a second connecting area (13), the first connecting area (12) being connected to the dome area (11), the second connecting area (13) being connected to the first connecting area (12), wherein an extension direction of the first connecting area (12) is substantially perpendicular to an extension direction of the second connecting area (13), and a surround (2) being connected to the first connecting area (12), the second connecting area (13), and the dome area (11), wherein the surround (2) does not completely cover the dome area (11); a surround (2) wherein one end of the surround (2) is connected to the dome area (11) of the vibrating diaphragm; a voice coil (4) located beneath the vibrating diaphragm (1);and a magnetic circuit located below the voice coil (4), wherein the magnetic circuit has a T-shaped yoke iron (51), the center or central region of the T-shaped yoke iron (51) being provided with a through-hole (5111) and the through-hole (5111) being opposite a central region of the vibrating diaphragm (1).

Description

BACKGROUNDTechnical FieldThis application relates to a loudspeaker and, more particularly, to a dome loudspeaker.Prior ArtA speaker is an electroacoustic transducer mainly capable of converting a current frequency into a sound and outputting the sound. The speaker functions as follows: a current flows through a voice coil to generate a magnetic field, and the magnetic field of the voice coil interacts with a magnetic field of a magnetic circuit to drive a vibration diaphragm to vibrate. In this way, a sound is generated.Speakers can be classified as cone speakers, flat speakers, dome speakers, horn speakers, and the like using various shapes of the vibration diaphragm. Dome speakers function primarily as mid- and tweeters. Dome speakers may be further classified as hard dome speakers and soft dome speakers according to the material of the dome. An example of such a device is known from GB 2 519 672 A and JP H05-183 990 A.The material of a vibration diaphragm of soft dome speakers may be a slapseide diaphragm, a silk diaphragm, a rubber diaphragm, a bulletproof fabric diaphragm, or the like. When the soft dome loudspeaker plays music, it works very well with high tones, i.e. at high frequencies. The soft dome speaker is suitable for playing general music, such as classical music or human voice. The material of a vibration diaphragm of hard dome speakers may be an aluminum alloy, titanium alloy, magnesium alloy, a titanium alloy laminate diaphragm, a glass diaphragm, a diamond diaphragm, or the like. A high sound played by the hard dome speaker has a bright sound and gives a metallic feel. Hard dome speakers are suitable for playing pop music, movie music, and movie effect music.An effective bandwidth range of an ordinary hard dome speaker is between 850 Hz and 15 KHz, and the sound pressure level is likely to change apparently when the bandwidth is less than 15 KHz. That is, an ordinary hard dome speaker still has problems in that the effective bandwidth range is insufficient and the SPL curve is not flat enough.SUMMARYAgainst this background, this invention provides a hard dome tweeter. The hard dome tweeter according to this invention includes a vibration diaphragm, a bead, a voice coil, and a magnetic circuit. The vibration membrane has a dome portion and a first connecting portion and a second connecting portion, the first connecting portion is connected to the dome portion, the second connecting portion is connected to the first connecting portion, an extending direction of the first connecting portion is perpendicular to an extending direction of the second connecting portion, and the bead is connected to the first connecting portion, the second connecting portion, and the dome portion, and the bead does not completely cover the dome portion.One end of the bead is connected to the dome portion of the vibration diaphragm. The voice coil is located below the vibration diaphragm. The magnetic circuit is located below the voice coil, and the magnetic circuit includes a T-shaped yoke iron, the center of the T-shaped yoke iron is provided with a through hole, and the through hole is opposed to a central position of the vibration diaphragm.In one embodiment, the voice coil includes a coil support and a coil, the coil support includes a driving portion and an extension portion, an angle is formed between the extension portion and the driving portion, the coil is fitted over the driving portion, the driving portion is laminated with the first connecting portion, and the extension portion is laminated with the dome portion.In one embodiment, the dome tweeter has an adhesive region which is located at an overlap region between the vibration membrane and the coil carrier of the voice coil.In one embodiment, the adhesive portion has an outer edge extending from the second connecting portion to the drive portion.In one embodiment, the dome tweeter comprises a sound absorbing cotton, wherein the sound absorbing cotton is located under the magnetic circuit and covers the through hole of the magnetic circuit.In one embodiment, the dome tweeter has a rear cavity which is placed over the sound-absorbing cotton.In one embodiment, the dome tweeter includes a back cover that covers a back cavity and the sound absorbing cotton.In one embodiment, the through hole of the T-shaped yoke iron has an arc edge.In an embodiment, the T-shaped yoke iron has a standing portion and a supporting portion, the standing portion stands vertically on the supporting portion, and the center of the standing portion is provided with the through hole.In an embodiment, the standing portion of the T-shaped yoke iron includes a first body segment and a second body segment, the first body segment extends along a direction perpendicular to the supporting portion, and the second body segment is inclined relative to the first body segment to be tapered.The dome speaker can effectively reduce a height resonance frequency and extend a high-frequency SPL curve so as to extend an effective bandwidth range to 600 Hz to 20 KHz, while ensuring flatness of the SPL curve within the effective bandwidth range.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a schematic three-dimensional view of an embodiment of a dome tweeter according to this application; FIG. 2 is a three-dimensional exploded structural drawing of an embodiment of a dome tweeter according to this application; FIG. 3 is a diagram of a substructure according to FIG. 2 ; FIG. 4 is a partial sectional view of an embodiment of a dome tweeter according to this invention; and FIG. 5 is an enlarged partial view according to "part 5" in FIG. 4.DETAILED DESCRIPTIONFor convenience in explanation, in this invention, the terms "above", "below", "left", and "right" in the drawings are intended to indicate relative reference positions between components, rather than limiting this application. Although the discussion below is presented for a 'tweeter', elements of the invention may be applied to any speaker; as such, the concepts should not be considered limited in application to this.Referring to FIG. 1 in combination with FIG. 2, FIG. 1 is a schematic three-dimensional representation of an appearance of an embodiment of a dome tweeter in accordance with this invention. FIG. 2 is a three-dimensional exploded structural drawing of an embodiment of a dome tweeter according to this application. An embodiment of the dome tweeter depicted in FIGS. 1 and 2 includes a vibration membrane 1, a bead 2, a voice coil 4, and a magnetic circuit 5. The dome tweeter may be a hard dome tweeter. The vibration membrane 1 has a dome region 11. One end of the bead 2 is connected to the dome portion 11 of the vibration diaphragm 1. The voice coil 4 is located below the vibration diaphragm 1, the magnetic circuit 5 is located below the voice coil 4, and the magnetic circuit 5 includes a T-shaped yoke iron 51, the center of the T-shaped yoke iron 51 is provided with a through hole 5111, and the through hole 5111 is opposed to a central position of the vibration diaphragm 1.When the voice coil 4 is supplied with current, a current flows through the voice coil 4 to generate a magnetic field. The magnetic field of the voice coil 4 interacts with a magnetic field of the magnetic circuit 5 to generate a magnetic induction force that drives the voice coil 4 to oscillate. In this manner, sound is generated using the vibration diaphragm 1. The through hole 5111 of the T-shaped yoke iron 51 of the magnetic circuit 5 increases a space volume under the vibration diaphragm 1, thus extending a reflection time of a sound wave under the vibration diaphragm 1, thereby effectively lowering a resonance frequency, and expanding an effective band width range.Further, the T-shaped yoke iron 51 has a standing portion 511 and a supporting portion 512. The standing portion 511 protrudes from and / or stands vertically on the supporting portion 512. The through hole 5111 is located toward or at the center of the standing portion 511. An end of the standing portion 511 of the T-shaped yoke iron 51 close to the vibration diaphragm 1 has an arc edge 5112, the arc edge 5112 extending forward and, in individual cases, through the through hole 5111. The standing portion 511 of the T-shaped yoke iron 51 has a first body segment 5113 and a second body segment 5114. The first body segment 5113 extends along a direction perpendicular to the supporting portion 512. The second body segment 5114 is inclined relative to the first body segment 5113, resulting in a conical shape or structure. A distance between the T-shaped yoke iron 51 and a magnet 52 may be adjusted, modified, and / or changed according to the shape of the standing portion 511. The magnetic field is thereby optimized.In addition, the magnetic circuit 5 further includes the magnet 52 and a flux concentration plate 53. The magnet 52 and the flux concentration plate 53 are preferably both annular. More preferably, the flux concentration plate 53 is fitted over the standing portion 511 to abut on the magnet 52. The T-shaped yoke iron 51 is a part of the magnetic circuit that allows magnetic field lines to smoothly flow through the T-shaped yoke iron 51. The T-shaped yoke iron 51 and the flux concentration plate 53 are made of a material having magnetic conductivity, and the magnet 52 is usually made of a permanent magnetic material.Referring to FIGS. 3 to 5 in combination, in the present invention, the vibration diaphragm 1 is a dome-shaped vibration diaphragm. The vibration diaphragm 1 has an outer profile having a semicircular dome shape, and a ball-cut dome portion 11 exists within a region surrounded by the outer profile. The vibration membrane 1 further comprises a first connecting region 12 and a second connecting region 13. One end of the first connecting portion 12 extends downward from the dome portion 11, and the second connecting portion 13 is connected to the other end of the first connecting portion 12. Here, an extending direction of the first connecting portion 12 is substantially perpendicular to an extending direction of the second connecting portion 13. a connecting portion of the vibration diaphragm 1 has a bent structure that increases the bonding intensity between the vibration diaphragm 1 and the bead 2, and further increases the rigidity of the vibration diaphragm 1. The vibration diaphragm 1 may be made of a hard material such as a metal, a semimetal, a plastic, or the like. For example, the vibration membrane 1 may be, but is not limited to, an aluminum alloy, titanium alloy, magnesium alloy, a titanium alloy laminate membrane, a glass membrane, or a diamond membrane.Referring to FIG. 4 in combination with FIG. 5, the bead 2 is arranged on an outer surface 112 of the edge of the dome portion 11 of the vibration membrane 1 along the outer profile of the vibration membrane 1. The bead 2 has a first end 21, a second end 22, and a buffer region 23 located between the first end 21 and the second end 22. The first end 21 and the second end 22 are two opposite ends of the bead 2, and the first end 21 of the bead 2 is laminated to the outer surface 112 of the dome portion 11. A portion of the buffer portion 23 between the first end 21 and the second end 22 of the bead 2 has an inverted U-shape. In this embodiment, the first end 21 of the bead 2 may be laminated with the first connecting portion 12, the second connecting portion 13, and the dome portion 11 of the vibration membrane 1. More specifically, and with continued reference to FIGS. 4 and 5, the first end 21 of the bead 2 includes a first abutting segment 211, a second abutting segment 212, and a third abutting segment 213. One end of the first adjacent segment 211 is connected to the buffer region 23. The second abutting segment 212 is located between the other end of the first abutting segment 211 and the third abutting segment 213. The first abutting segment 211 of the bead 2 is laminated or bonded to the second connecting portion 13 of the vibration membrane 1, the second abutting segment 212 is laminated or bonded to the first connecting portion 12 of the vibration membrane 1, and the third abutting portion 213 is laminated or bonded to a part of the dome portion 11 of the vibration membrane 1. By forming the first end 21 of the bead 2 corresponding to the vibration diaphragm 1, the bead 2 and the vibration diaphragm 1 can be closely joined to each other; at the same time, a lamination area between the bead 2 and the vibration diaphragm 1 is enlarged. Thereby, the bonding stability of the joint between the vibration membrane 1 and the bead 2 is increased, the rigidity of the vibration membrane 1 is further increased, the probability of occurrence of high frequency tone-depth is decreased, and the uniformity of the SPL curve is increased.Referring further to FIGS. 2, 4 and 5, the voice coil 4 includes a coil bobbin 41 and a coil 42. The coil carrier 41 is circular column-shaped. The coil 42 is wound around the one end of the edge portion of the bobbin 41. The bobbin 41 is located below the center of the dome portion 11 of the vibration diaphragm 1, and the other end of the bobbin 41 is connected to an inner surface 111 of the vibration diaphragm 1. A part of the T-shaped yoke iron 51 of the magnetic circuit 5 enters the coil bobbin 41 of the voice coil 4, and a magnetic circuit gap G exists between the magnetic circuit 5 and the voice coil 4. the coil 42 of the voice coil 4 is located inside the magnetic circuit gap G so that the voice coil 4 can move smoothly inside the magnetic circuit gap G.Referring to FIGS. 4 and 5, in an embodiment, the bobbin 41 of the voice coil 4 has a driving portion 411 and an extension portion 412 to improve the contact area between the vibration diaphragm 1 and the voice coil 4. The driving portion 411 is a straight cylinder structure, and the extension portion 412 extends along one end of the driving portion 411. An angle may be formed between the extension portion 412 and the drive portion 411. The extension portion 412 has an arc surface, and an arc of the extension portion 412 corresponds to an arc of the inner surface 111 of the dome portion 11 of the vibration diaphragm 1, thereby the extension portion 412 of the voice coil 4 can be closely connected to the inner surface 111 of the dome portion 11 of the vibration diaphragm 1, and the drive portion 411 of the voice coil 4 can be closely connected to the first connecting portion 12 of the vibration diaphragm 1. In this embodiment, the contact area between the vibration diaphragm 1 and the voice coil 4 can be significantly increased, so that the voice coil 4 can drive the vibration diaphragm 1 to move more precisely. This increases the sound generation efficiency and the loadability. At the same time, the rigidity of the contact surface region is significantly improved. This is advantageous for high frequency bandwidth extension of the SPL curve.Referring further to Fig. 5, in one embodiment, the loudspeaker according to this invention may have an adhesive portion 6. An overlapping portion between the vibration membrane 1 and the voice coil 4 is filled with the adhesive portion 6 so that the vibration membrane 1 and the voice coil 4 are firmly bonded to each other. More specifically, the adhesive portion 6 according to this embodiment is disposed at a position on the inner surface 111 of the dome portion 11 of the vibration diaphragm corresponding to the extension portion 412 of the voice coil 4, and is disposed at the first connecting portion 12 of the vibration diaphragm 1, and is further disposed at a corresponding position on the bobbin 41 of the voice coil 4. The adhesive portion 6 may swell from the connection between the first connecting portion 12 and the second connecting portion 13 to the second connecting portion 13 of the vibration membrane 1. The swelling of the adhesive portion 6 saturates and forms an outer edge 61. the outer edge 61 is an arc edge and extends from the second connecting portion of the vibration diaphragm 1 to the driving portion 411 of the bobbin 41 of the voice coil 4. therefore, the adhesive portion 6 can firmly and / or closely join the vibration diaphragm 1 and the voice coil 4, and the swelling of the adhesive portion 6 can further ensure the bonding stability of the connection between the vibration diaphragm 1 and the voice coil, increase the rigidity of the vibration diaphragm 1, decrease the probability of occurrence of high-frequency sound sound sound sound sound and increase the uniformity of the SPL curve.Referring to FIG. 2 in combination with FIG. 4, in an embodiment, the speaker according to this invention may further include a sound absorbing cotton 7 to further increase the space volume under the vibration diaphragm 1 and reduce the interference of a standing wave. The sound absorbing cotton 7 is disposed under the magnetic circuit 5. Specifically, the sound-absorbing cotton 7 is located below the T-shaped yoke iron 51 of the magnetic circuit 5 and covers the through hole 5111 of the T-shaped yoke iron 51 of the magnetic circuit 5. The sound-absorbing cotton 7 according to this embodiment is cylindrical, but the shape of the sound-absorbing cotton 7 is not limited thereto. Therefore, the sound absorbing cotton 7 can reduce noise and further reduce a resonance frequency, extend an effective bandwidth range, and tune the uniformity of acoustic resistance behind the vibration diaphragm 1 and a total impedance curve.Referring to FIGS. 2 and 4, in one embodiment, the dome tweeter may further include a rear cavity 8 and a rear cover 9 to have a complete speaker box behind the vibration membrane 1. This can avoid interference from a rear sound field of the vibration diaphragm 1 with a front sound wave and prevent occurrence of an acoustic short circuit. The rear cavity 8 is closed outside the sound absorbing cotton 7, and the rear cover 9 covers the rear cavity 8 and the sound absorbing cotton 7. The rear cavity 8 according to this embodiment has a bushing hole 81 passing through two ends. The bushing hole 81 of the rear cavity 8 covers the sound absorbing cotton 7. the rear cover 9 may be a circular sheet structure, but is not limited thereto. A peripheral profile of the rear cover 9 corresponds to a peripheral profile of the rear cavity 8, and the rear cover 9 is connected to an end of the rear cavity 8 to close the sleeve hole 81 of the rear cavity 8. Therefore, the space behind the vibration diaphragm 1 is a completely enclosed space including the through hole 5111 of the T-shaped yoke iron 51, the sound absorbing cotton 7, the rear cavity 8, and the rear cover 9. In addition, for the rear cavity 8 and the rear cover 9, an aluminum alloy material that helps to remove heat from the magnetic circuit 5 and improve the load capacity is preferably used.Referring to FIGS. 4 and 5, in one embodiment, the dome tweeter may further include a short ring C. The short-circuiting ring C is fitted over an end of the standing portion 511 of the T-shaped yoke iron 51 of the magnetic circuit 5 which is close to the vibration diaphragm 1. More specifically, the short ring C has a central hole C 1. The short-circuiting ring C covers a part of the arc edge 5112, and a part of the arc edge 5112 near the through hole 5111 faces the central hole C 1 of the short-circuiting ring C. The short-circuiting ring C is made of a highly conductive metal. The short-circuit ring C according to this embodiment may be, but is not limited to, a copper ring. As a result, the inductive reactance at high frequencies can be reduced, bandwidth expansion at high frequencies can be achieved, and the distortion factor is reduced by electromagnetic transduction of the short-circuiting ring C and the effect of the magnetic field of the magnetic circuit 5.Referring further to FIG. 2 in combination with FIG. 5, the hard dome tweeter may further include a bracket 3. The holder 3 has a circular structure and has a fitting hole 31. The first end 22 of the bead 2 is connected to the bracket 3 along the fitting hole 31. The holder 3 fits to the bead 2 so that the vibration diaphragm 1 is supported and held. In order to further improve the structural stability of the entire device, in one embodiment, the bracket 3 has a communication hole 32. The communication hole 32 is located around the fitting hole 31, and the flux concentration plate 53 of the magnetic circuit 5 has a connection member 531. Thus, the connecting member 531 of the flux concentration plate 53 of the magnetic circuit 5 can be correspondingly inserted into the connecting hole 32 of the holder 3 so that the magnetic circuit 5 is located on the holder 3. This improves the structural stability of the entire device.Although this application is disclosed using the embodiments as described above, the embodiments are not intended to limit this invention. Those skilled in the art can make some variations and modifications without departing from the scope of this application. Therefore, the scope of this application should be subject to the scope defined by the appended claims.

Claims

A dome loudspeaker comprising: a vibration diaphragm (1) comprising a dome portion (11) and a first connecting portion (12) and a second connecting portion (13), the first connecting portion (12) being connected to the dome portion (11), the second connecting portion (13) being connected to the first connecting portion (12), wherein an extension direction of the first connecting portion (12) is substantially perpendicular to an extension direction of the second connecting portion (13), and a bead (2) is connected to the first connecting portion (12), the second connecting portion (13) and the dome portion (11), wherein the bead (2) does not completely cover the dome portion (11); a bead (2), wherein an end of the bead (2) is connected to the dome portion (11) of the vibration diaphragm; a voice coil (4) located below the vibration diaphragm (1); and a magnetic circuit located below the voice coil (4), the magnetic circuit comprising a T-shaped yoke iron (51), wherein the center or the central portion of the T-shaped yoke iron (51) is provided with a through hole (5111), and the through hole (5111) is opposed to a central portion of the vibration diaphragm (1).The dome speaker according to claim 1, wherein the T-shaped yoke iron (51) has a standing portion (511) and a supporting portion (512), the standing portion (511) stands vertically on the supporting portion (512) or is located thereon, and the center or the central portion of the standing portion (511) is provided with the through hole (5111).The dome speaker according to claim 2, wherein the standing portion (511) of the T-shaped yoke iron (51) includes a first body segment (5113) and a second body segment (5114), the first body segment (5113) extends along a direction substantially perpendicular to the supporting portion (512), and the second body segment (5114) is inclined relative to the first body segment (5112) to form a conical portion or to have a cone shape.The dome speaker according to any one of the preceding claims, wherein the voice coil (4) includes a coil support (41) and a coil (42), the coil support (41) includes a driving portion (411) and an extension portion (412), an angle is formed between the extension portion (412) and the driving portion (411), the coil (4) fits closely over the driving portion (411), the driving portion (411) is laminated with the first connecting portion (12), and the extension portion (412) is laminated with the dome portion (11).Dome loudspeaker according to one of the preceding claims, having an adhesive region (6) which is located at an overlap region between the vibration membrane (1) and the coil carrier (41) of the vibration coil (4).The dome speaker according to claim 5, wherein the adhesive portion (6) has an outer edge (61) extending from the second connecting portion (13) to the driving portion (411).Dome loudspeaker according to any one of the preceding claims, comprising a sound-absorbing cotton (7) located under the magnetic circuit and covering the through hole (5111) of the magnetic circuit.Dome loudspeaker according to one of the preceding claims, having a rear cavity (8) enclosing the sound-absorbing cotton (7).Dome loudspeaker according to claim 8, comprising a rear cover (9) covering the rear cavity (8) and the sound absorbing cotton (7).Dome loudspeaker according to any of the preceding claims, wherein the loudspeaker is a tweeter.

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