TWI403186B - Coil and loudspeaker using the same - Google Patents

Description

Voice coil and speaker using the voice coil

The present invention relates to a voice coil and a speaker using the same.

An electric speaker typically includes a voice coil, a voice coil bobbin, a magnetic field system, and a diaphragm. The voice coil is wound around the periphery of one end of the voice coil bobbin. The voice coil bobbin is connected to the diaphragm. During operation, the vibration generated by the voice coil fixed on the voice coil bobbin in the magnetic field system pushes the diaphragm to vibrate and emit sound waves. The voice coil is the drive unit of the speaker. The voice coil is in a magnetic field environment. When a current is applied to the voice coil, the voice coil will perform piston movement under the action of the magnetic field, thereby driving the diaphragm to vibrate to push the diaphragm to reciprocate back and forth, thereby pushing the surrounding air to move and emit sound waves. The volume of the speaker is an important indicator of the merits of the speaker. The volume of the speaker is related to the input power and the electroacoustic conversion efficiency. However, due to the specific strength of the material, the input power of the speaker cannot be increased without limit. The input power of a typical micro speaker is only 0.3W~0.5W. On the other hand, the electroacoustic conversion efficiency of the speaker cannot be further improved due to the large weight per unit area of the prior material. Therefore, in order to increase the input power and conversion efficiency of the speaker, and thereby increase the volume of the speaker, it is necessary to further increase the specific strength of each component in the speaker and reduce the weight of each component.

The voice coil should also be lightweight to meet the requirements of easy vibration. The voice coil is usually an enameled wire structure, that is, the wire is covered with an insulating material. Wires of the prior art are often made of metallic copper. However, the metallic copper has a relatively high density of 8.9 g/cm 3 , resulting in a heavier weight of the voice coil at a certain diameter and length. When the voice coil is heavier, the piston movement consumes a large amount of power, which affects the sound power and sounding effect of the speaker.

In view of this, it is indeed necessary to provide a light weight voice coil and a speaker using the voice coil.

A speaker includes a voice coil bobbin, a voice coil, a diaphragm, and a magnetic field system. The voice coil is disposed at a periphery of the voice coil bobbin, and the voice coil includes at least one wire wound around an outer surface of the voice coil bobbin. The diaphragm is coupled to the voice coil bobbin. The magnetic field system has a magnetic field gap in which the voice coil is disposed. The wire includes a nanocarbon line-like structure and an insulating layer overlying the outer surface of the nanocarbon line-like structure. The nanocarbon line-like structure includes a plurality of carbon nanotubes.

A voice coil for setting the periphery of the voice coil bobbin in a speaker. The voice coil includes at least one wire wound around an outer surface of the voice coil bobbin. The wire includes a nano carbon line structure and an insulating layer disposed on the surface of the nanocarbon line structure. The nanocarbon line-like structure includes a plurality of carbon nanotubes.

Compared with the prior art, the conductive core of the voice coil of the speaker provided by the present invention adopts a nano carbon line structure, and the nano carbon line structure includes a plurality of carbon nanotubes, and the density of the carbon nanotubes is small. , which is 1.35 g/cm 3 , and the voice coil using the nano carbon line-like structure is light in weight under a certain diameter and length, and the voice coil consumes less power when doing piston movement, that is, the power is constant. In the case, the amplitude of the voice coil using the nanocarbon line-like structure is large, so that the speaker has a large sounding power and a good sounding effect.

Hereinafter, a speaker of an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Referring to Figures 1 and 2, the present invention provides a speaker 100. The speaker 100 includes a bracket 110, a magnetic field system 120, a voice coil 130, a voice coil bobbin 140, a diaphragm 150 and a centering piece 160. The magnetic field system 120 is fixed to the bracket 110. The voice coil 130 is disposed on an outer surface of the voice coil bobbin 140 near one end of the magnetic field system 120 and is received in the magnetic field system 120. One end of the diaphragm 150 and the centering piece 160 is fixed to the bracket 110, and the other end is fixed to the voice coil bobbin 140.

The bracket 110 is a truncated cone structure having a cavity 111 and a bottom portion 112. The cavity 111 is used to accommodate the diaphragm 150 and the centering piece 160. The bottom portion 112 also has a central aperture 113 for nesting the magnetic field system 120. The bracket 110 is relatively fixed to the magnetic field system 120 by the bottom portion 112.

The magnetic field system 120 includes a magnetically permeable lower plate 121, a magnetically permeable upper plate 122, a magnet 123, and a magnetic core stud 124. The opposite axial ends of the magnet 123 are respectively sandwiched by the concentric magnetic lower plate 121 and the magnetic conductive upper plate 122. The magnetically permeable upper plate 122 and the magnet 123 are both annular structures, and the magnetically permeable upper plate 122 and the magnet 123 enclose a cylindrical space in the magnetic field system 120, and the cylindrical space is a cylindrical structure. space. The magnetic core stud 124 is received in the cylindrical space and passes through the central hole 113. The magnetic core stud 124 extends from the magnetically permeable lower plate 121 to the magnetic conductive upper plate 122 and forms an annular magnetic field gap 125 with the magnet 123 to accommodate the voice coil 130. The magnetic field gap 125 has a constant magnetic field of a certain magnetic induction density. The magnetic field system 120 is fixed to the bottom portion 112 of the bracket 110 through the magnetic conductive upper plate 122, and the fixing method may be screwing, mating fixing, bonding, or the like. In this embodiment, the magnetic conductive upper plate 122 and the bottom portion 112 are fixed by screwing.

The voice coil bobbin 140 is a hollow cylindrical structure that is disposed concentrically with the magnetic core stud 124 and sleeved on the magnetic core stud 124 and received in the magnetic field gap 125 . An outer surface of the voice coil bobbin 140 is fixed to the voice coil 130, and an end thereof away from the magnetic field system 120 is fixed at a center position of the vibrating membrane 150. When the voice coil bobbin 140 vibrates in the axial direction thereof along with the voice coil 130, the vibrating membrane 150 is caused to vibrate, thereby moving the air around the vibrating membrane 150 to generate sound waves. The voice coil bobbin 140 is made of a material resistant to high temperature, high strength and low density. In the present embodiment, the voice coil bobbin 140 is a paper tube.

The diaphragm 150 is a sounding unit of the speaker 100. The shape of the diaphragm 150 is not limited, and is related to its specific application. For example, when the diaphragm 150 is applied to the large speaker 100, the diaphragm 150 may be a hollow cone structure; when the diaphragm 150 is applied to the micro speaker At 100 o'clock, the diaphragm 150 may have a disk-like structure. The bottom end of the diaphragm 150 and the voice coil bobbin 140 can be fixed by bonding, and the outer edge of the other end is connected to the bracket 110, that is, the end of the diaphragm 150 connected to the bracket 110 can move up and down. In order to achieve the effect of vibration and sound. In this embodiment, the diaphragm 150 is a hollow cone structure.

The centering piece 160 is a wavy annular structure composed of a plurality of concentric rings. The inner edge of the centering piece 160 is sleeved on the voice coil bobbin 140 for supporting the voice coil bobbin 140. The outer edge of the centering piece 160 is fixed to the bracket 110 near the center hole. One end of 113. The centering piece 160 has a large radial rigidity and a small axial rigidity, so that the voice coil 130 is freely moved up and down in the magnetic field gap 125 without lateral movement, avoiding the voice coil 130 and the magnetic field. The system 120 touches and functions to fix the center of the diaphragm 150.

Referring to FIG. 3 together, the voice coil 130 is disposed at the periphery of the voice coil bobbin 140 and is located at one end of the voice coil bobbin 140 and is received in the magnetic field gap 125. The voice coil 130 is a drive unit of the speaker 100. The voice coil 130 is electrically coupled to an external circuit through a voice coil lead 132 to cause an external circuit to input an audio electrical signal to the voice coil 130. The voice coil 130 is a structure in which a wire is wound around the outer surface of the voice coil bobbin 140. The voice coil 130 can be a single-layer multi-turn structure or a multi-layer multi-turn structure. The number of turns of the voice coil 130 is related to the power of the speaker 100. The more the number of turns of the voice coil 130, the greater the power of the speaker 100, the smaller the number of turns of the voice coil 130, and the smaller the power of the speaker 100. The larger the diameter of the wire in the voice coil 130, the greater the current that the voice coil 130 can withstand. When the voice coil 130 receives an audio electrical signal, the voice coil 130 produces a magnetic field that varies as a function of the intensity of the audio electrical signal, which occurs between the magnetic field generated by the magnetic field system 120 and the magnetic field generated by the magnetic field system 120. The interaction forces the voice coil 130 to produce piston motion along its axial direction. The voice coil 130 drives the voice coil bobbin 140 to perform piston movement. Since one end of the voice coil bobbin 140 is connected to the vibrating membrane 150, vibration of the vibrating membrane 150 is caused, and the vibrating membrane 150 pushes the surrounding air to cause the speaker 100 to emit sound.

The wire of the voice coil 130 includes a conductive core wire and an insulating layer covering the outer surface of the conductive core wire, that is, an enamel wire structure. The diameter of the voice coil 130 is substantially equal to the diameter of the voice coil bobbin 140. The diameter of the wire is approximately equal to the sum of the diameters of the conductive core and the insulating layer. In this embodiment, the voice coil 130 has a diameter of 0.1 mm to 50 mm. The insulating layer has a thickness of 10 micrometers to 0.1 millimeters. The insulating layer is composed of an insulating varnish, which may include polyester, polyurethane, polyimine, polyamidimide, and the like. The insulating layer may also be other insulating materials, including plastics, rubber, and the like.

The conductive core wire is a nano carbon line structure. The nanocarbon line-like structure includes a plurality of carbon nanotubes, and the plurality of carbon nanotubes are connected end to end. Since the plurality of carbon nanotubes are connected end to end, the nanocarbon line-like structure has better electrical conductivity. The length of the nanocarbon line-like structure is not limited, and the diameter is preferably 0.05 mm to 20 mm. The carbon nanotubes include one or more of a single-walled carbon nanotube, a double-walled carbon nanotube, and a multi-walled carbon nanotube. The single-walled carbon nanotube has a diameter of 0.5 nm to 50 nm, the double-walled carbon nanotube has a diameter of 1.0 nm to 50 nm, and the multi-walled carbon nanotube has a diameter of 1.5. Nano ~ 50 nm.

The nanocarbon pipeline-like structure includes at least one nanocarbon pipeline including a plurality of carbon nanotubes connected end to end. When the nanocarbon pipeline structure comprises a plurality of nano carbon pipelines, the nanocarbon pipeline structure is a bundle structure composed of a plurality of nano carbon pipelines arranged in parallel or spirally wound by a plurality of nano carbon pipelines. Stranded structure.

The nanocarbon line can be a non-twisted nanocarbon line or a twisted nanocarbon line. The non-twisted nano carbon line is obtained by treating a carbon nanotube film by an organic solvent. Referring to FIG. 4, the non-twisted nanocarbon pipeline includes a plurality of carbon nanotubes arranged in the axial direction of the nanocarbon pipeline and connected end to end. The plurality of carbon nanotubes are parallel to each other. The axial direction of the plurality of carbon nanotubes is substantially parallel to the axial direction of the non-twisted nanocarbon line. Preferably, the non-twisted nanocarbon pipeline comprises a plurality of carbon nanotube segments, and the plurality of carbon nanotube segments are connected end to end by Van der Waals force, and each of the carbon nanotube segments comprises a plurality of mutually parallel and The carbon nanotubes are tightly combined by Van der Valli. The carbon nanotube segments have any length, thickness, uniformity, and shape. The non-twisted nano carbon line is not limited in length and has a diameter of 0.5 nm to 100 μm.

The twisted nanocarbon pipeline is obtained by twisting both ends of the carbon nanotube film in the opposite direction by a mechanical force. Referring to FIG. 5, the twisted nanocarbon pipeline includes a plurality of carbon nanotubes connected end to end. The axial direction of the plurality of carbon nanotubes extends along the axial direction of the twisted nanocarbon line. Preferably, the twisted nanocarbon pipeline comprises a plurality of carbon nanotube segments, and the plurality of carbon nanotube segments are connected end to end by Van der Waals force, and each of the carbon nanotube segments comprises a plurality of mutually parallel and The carbon nanotubes are tightly combined by Van der Valli. The carbon nanotube segments have any length, thickness, uniformity, and shape. The twisted nanocarbon line is not limited in length and has a diameter of 0.5 nm to 100 μm. The nano carbon pipeline and its preparation method can be found in Fan Shoushan et al., which was applied for on November 5, 1991. The announcement of the Republic of China on May 16, 1992 is No. I303239. Rope and its manufacturing method", applicant: Hong Fujin Precision Industry (Shenzhen) Co., Ltd., and Taiwan Patent Application No. 200724486, published on December 16, 1994, "Nano Carbon Tube Wire and Method of Making Same "Applicant: Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. In order to save space, only the above is cited, but all the technical disclosures of the above application are also considered as part of the technical disclosure of the present application.

Further, the nanocarbon line may be treated with a volatile organic solvent. Under the action of the surface tension generated by the volatilization of volatile organic solvents, the adjacent carbon nanotubes in the treated nanocarbon pipeline are tightly bonded by van der Waals force, and the diameter and specific surface area of the nanocarbon pipeline are further reduced. Small, so that its density and strength are further increased.

The conductive core of the voice coil of the speaker provided by the invention adopts a nano carbon line structure, and the nano carbon line structure comprises a plurality of carbon nanotubes, and the density of the carbon nanotubes is small, about 1.35 g/ Cubic centimeters, so the quality of the voice coil is lighter, and the voice coil consumes less power when doing piston movement, so that the speaker has a larger sound power and better sounding effect.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by those skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

140‧‧‧ voice coil skeleton

100‧‧‧Speakers

110‧‧‧ bracket

111‧‧‧ Cavity

112‧‧‧Bottom of the bracket

113‧‧‧ center hole

120‧‧‧ Magnetic circuit system

121‧‧‧Magnetic lower plate

122‧‧‧Magnetic upper plate

123‧‧‧ magnet

124‧‧‧magnetic core column

125‧‧‧ Magnetic field gap

130‧‧‧ voice coil

132‧‧‧ voice coil leads

150‧‧‧Vibration film

160‧‧‧Centering piece

1 is a schematic exploded view of a speaker provided by an embodiment of the present invention.

2 is a schematic cross-sectional view of the speaker of FIG. 1.

FIG. 3 is a schematic structural view of a voice coil and a voice coil bobbin in the speaker of FIG. 1. FIG.

Figure 4 is a scanning electron micrograph of a non-twisted nanocarbon line employed in a nanocarbon line-like structure in the voice coil of a loudspeaker.

Figure 5 is a scanning electron micrograph of a twisted nanocarbon line employed in a nanocarbon line-like structure in the voice coil of a loudspeaker.

140‧‧‧ voice coil skeleton

100‧‧‧Speakers

110‧‧‧ bracket

111‧‧‧ Cavity

112‧‧‧Bottom of the bracket

113‧‧‧ center hole

120‧‧‧ Magnetic circuit system

121‧‧‧Magnetic lower plate

122‧‧‧Magnetic upper plate

123‧‧‧ magnet

124‧‧‧magnetic core column

130‧‧‧ voice coil

150‧‧‧Vibration film

160‧‧‧Centering piece

Claims (15)

A speaker comprising:
a voice coil skeleton;
a voice coil disposed at a periphery of the voice coil bobbin, the voice coil including at least one wire wound around an outer surface of the voice coil bobbin;
a vibrating membrane coupled to the voice coil bobbin; and a magnetic field system having a magnetic field gap, the voice coil being disposed in the magnetic field gap;
The improvement is that the wire comprises a nano carbon line structure and an insulating layer is disposed on the outer surface of the nano carbon line structure, and the nano carbon line structure comprises a plurality of carbon nanotubes. The speaker of claim 1, wherein the nanocarbon line-like structure comprises a plurality of carbon nanotubes connected end to end by van der Waals force. The speaker of claim 2, wherein the nanocarbon line-like structure is composed of a plurality of carbon nanotubes connected end to end by a van der Waals force. The speaker according to claim 1, wherein the nanocarbon line-like structure has a diameter of 0.05 mm to 50 mm. The speaker of claim 1, wherein the nanocarbon line-like structure comprises at least one nano carbon line. The speaker of claim 5, wherein the nanocarbon line-like structure comprises a plurality of nanocarbon pipelines arranged in parallel to form a bundle structure. The speaker according to claim 5, wherein the nanocarbon line-like structure comprises a plurality of nano carbon pipelines twisted to each other to form a stranded structure. The speaker according to claim 5, wherein the plurality of carbon nanotubes in the nanocarbon pipeline are connected end to end and the axial direction of the plurality of carbon nanotubes is substantially parallel to the carbon nanotube pipeline. Axial. The speaker according to claim 5, wherein the plurality of carbon nanotubes in the nanocarbon pipeline are connected end to end and the axial axial extension of the plurality of carbon nanotubes along the axial carbon nanotube line . The speaker according to claim 5, wherein the nano carbon line has a diameter of 0.5 nm to 100 μm. The speaker according to claim 1, wherein the insulating layer has a thickness of 10 μm to 0.1 mm. The speaker according to claim 1, wherein the insulating layer is made of polyester, polyurethane, polyimine or polyamidimide. The speaker according to claim 1, wherein the voice coil is a single-layer multi-turn structure formed by spirally winding the wire around an outer surface of the voice coil bobbin. The speaker according to claim 1, wherein the voice coil is a multi-layered multi-turn structure formed by spirally winding the wire around an outer surface of the voice coil bobbin. a voice coil for arranging a periphery of a voice coil bobbin in a speaker, comprising at least one wire wound around an outer surface of the voice coil bobbin, the improvement being that the wire comprises a nano carbon line structure and an insulation layer setting On the surface of the nanocarbon line-like structure, the nanocarbon line-like structure includes a plurality of carbon nanotubes.