Double-coil single-magnetic-circuit earphone loudspeaker and design method thereof

Abstract

The invention discloses a double-coil single-magnetic-circuit earphone loudspeaker and a design method thereof, and belongs to the field of loudspeakers, the double-coil single-magnetic-circuit earphone loudspeaker comprises a vibrating diaphragm and a magnet which are arranged in sequence, the edge of the vibrating diaphragm is arranged on a support, a voice coil arranged on the magnet in a sleeving mode is arranged on the side, facing the magnet, of the vibrating diaphragm, and the voice coil is of an integrated structure formed by winding an upper wire and a lower wire in parallel; and the upper and lower double-wire parallel winding integrated structure and the magnet are concentrically arranged. According to the earphone loudspeaker with the double coils and the single magnetic circuit and the design method of the earphone loudspeaker, on the premise that the size of the loudspeaker is not increased, the effective length of the voice coil wire is increased by winding the voice coil in parallel through the upper wire and the lower wire, and therefore the SPL value of the loudspeaker is increased.

Description

Technical Field

[0001] The present invention relates to the field of loudspeakers, and in particular to a double-coil single-magnetic-circuit earphone loudspeaker and a design method thereof. Background Art

[0002] Headphone speakers are usually dynamic speakers, which are generally composed of U iron, magnet, washer, bracket, voice coil, sound membrane and terminal. The working principle is: according to Faraday's law, when a current-carrying conductor passes through a magnetic field, it will be subjected to an electromotive force, the direction of which conforms to Fleming's left-hand rule. The force is perpendicular to the direction of the current and magnetic field, and the magnitude of the force is proportional to the current, wire length and magnetic flux density. Therefore, when the voice coil is input with alternating current, the voice coil is subjected to an alternating driving force, generating alternating motion, thereby driving the sound membrane to vibrate, repeatedly pushing the air to produce sound.

[0003] The existing earphone speaker structure is as follows:

[0004] CN202120599341.0 discloses a headphone speaker, which includes a magnet, a washer, a york, a bracket, a voice coil, and a diaphragm assembly. A cavity is provided inside the magnet, and a protrusion is provided on the upper end of the magnet. The washer and the york are provided inside the cavity, and the york is provided at the upper end of the washer. A groove is provided inside the bracket, and the groove is snap-connected with the protrusion. The voice coil is a ring-shaped coil, and the voice coil is fixedly connected to the upper end of the york. The diaphragm assembly is provided at the upper end of the voice coil, and the diaphragm assembly is fixedly connected to the bracket.

[0005] CN202322482415.4 discloses an air conduction bass reflex headphone speaker, comprising a bracket, a U-iron, a magnet, a washer, a PCB board, a cover plate, a voice coil, a sound membrane, a sound inlet, a sound outlet and a sound guide channel, wherein the open end of the U-iron is fixed to the inner ring of the bracket, the magnet is arranged inside the U-iron, the washer is arranged on the magnet, the outer circumference of the sound membrane is fixed to the outer ring of the bracket, the voice coil is fixed on the sound membrane and is located in the gap between the inner wall of the bracket and the outer circumference of the magnet and the washer, the sound guide channel is in the shape of an arc and is provided with a sound inlet at its bottom, the cover plate is in the shape of an arc and the arc length is smaller than the sound guide channel, after the cover plate is installed, the two ends of the sound guide channel are connected to the outside to form a sound outlet, and the PCB board is installed on a platform between the two ends of the arc of the sound guide channel.

[0006] CN202322209193.9 discloses a loudspeaker and an open-end headphone, the loudspeaker comprising a magnetic circuit system, a vibration system and a suspension, the magnetic circuit system comprising a basin and a magnetic circuit assembly arranged on the basin, the magnetic circuit assembly forming a magnetic gap; the vibration system comprising a diaphragm and a voice coil assembly, one end of the voice coil assembly being inserted in the magnetic gap, the other end being connected to the diaphragm, and the edge of the diaphragm being connected to the basin; the suspension is arranged on the periphery of the voice coil assembly, one end of the suspension is connected to the voice coil assembly, and the other end is connected to the basin; wherein the suspension and the diaphragm are spaced apart along the axial direction of the voice coil assembly, and the spacing between the suspension and the diaphragm along the axial direction of the voice coil assembly is 0.05mm to 2mm.

[0007] It can be seen that the voice coil of the existing headphone speaker is wound by a single wire. Under the limitation of the speaker size, the effective length of the voice coil is small and the sound pressure sensitivity is low. Summary of the invention

[0008] To solve the above problems, the present invention provides a double-coil single-magnetic-circuit headphone speaker and a design method thereof. Without increasing the size of the speaker, the voice coil is wound in parallel with upper and lower wires, thereby increasing the effective length of the voice coil wire and improving the SPL value of the speaker.

[0009] To achieve the above-mentioned purpose, the present invention provides a double-coil single-magnetic circuit headphone speaker, including a diaphragm and a magnet arranged in sequence, the edge of the diaphragm is arranged on a bracket, and a voice coil sleeved on the magnet is arranged on the side of the diaphragm facing the magnet, the voice coil is an integrated structure with upper and lower double wires wound in parallel, and the upper and lower double wires wound in parallel are both concentrically arranged with the magnet.

[0010] Preferably, the upper and lower double-wire parallel winding integrated structure includes a lower voice coil and an upper voice coil connected in parallel, and the lower voice coil and the upper voice coil are output in parallel to form two parallel loops.

[0011] Preferably, the upper voice coil and the lower voice coil are both made of enameled wire, and the output ends of the upper voice coil and the lower voice coil are welded to the bracket.

[0012] The design method of a double-coil single-magnetic-circuit headphone speaker comprises the following steps:

[0013] S1. Calculate the axial vibration force F of the diaphragm based on the following formula:

[0014] F=BLI(1)

[0015] Where, B is the magnetic induction intensity in the magnetic gap, in T; L is the effective length of the voice coil, in m; I is the current flowing through the voice coil, in A;

[0016] S2. Calculate the amplitude ξ of the diaphragm:

[0017]

[0018] Where Pe represents electric power; η o represents the electroacoustic conversion efficiency, η o represents frequency; a represents equivalent radius;

[0019] The calculation formula of electroacoustic conversion efficiency is as follows:

[0020]

[0021] In the formula, ρ o represents the air density; c represents the speed of sound; BL represents the electric coupling coefficient, where B is the magnetic induction intensity in the magnetic gap, L is the effective length of the voice coil; S d Represents the equivalent radiation area; M ms represents the equivalent vibrating mass;

[0022] S3. Calculate the sound pressure level SPL:

[0023] SPL=112+10lgη o (4)

[0024] S4, substituting the set SPL value into formula (3) to solve the effective length L of the voice coil;

[0025] S5. Based on the effective length L of the voice coil obtained in step S4, the upper and lower wires are wound in parallel as a whole, thereby obtaining a voice coil.

[0026] The present invention has the following beneficial effects:

[0027] Without increasing the size of the speaker, the voice coil is wound in parallel with upper and lower wires, which increases the effective length of the voice coil wire and improves the SPL value of the speaker.

[0028] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A longitudinal cross-sectional view of a double-coil single-magnetic-circuit earphone speaker of the present invention;

[0030] Figure 2 A top view of a double-coil single-magnetic-circuit headphone speaker of the present invention;

[0031] Figure 3 for Figure 2 AA cross section in;

[0032] Figure 4 for Figure 3 The enlarged view of point B in the figure;

[0033] Figure 5FIG. 4 is an SPL frequency curve diagram of an embodiment of the present invention.

[0034] Among them: 1. Voice coil; 11. Upper voice coil; 12. Lower voice coil; 2. Diaphragm; 3. Magnet. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention are further described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not intended to limit the embodiments of the present invention. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions.

[0036] It should be noted that the terms "include", "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or devices.

[0037] Like reference numerals and letters denote similar items in the following drawings, and thus, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0038] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0039] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] like Figure 1-Figure 4As shown, a double-coil single-magnetic-circuit headphone speaker comprises a diaphragm 2 and a magnet 3 arranged in sequence, the edge of the diaphragm 2 is arranged on a bracket, and a voice coil 1 sleeved on the magnet 3 is arranged on the side of the diaphragm 2 facing the magnet 3, the voice coil 1 is an integrated structure of upper and lower double-wire parallel winding, and the upper and lower double-wire parallel winding integrated structure are both arranged concentrically with the magnet 3. Specifically, the upper and lower double-wire parallel winding integrated structure comprises a lower voice coil 12 and an upper voice coil 11 connected in parallel, and the lower voice coil 12 and the upper voice coil 11 are output in parallel to form two parallel circuits.

[0041] The upper voice coil 11 and the lower voice coil 12 are both made of enameled wire, and the output ends of the upper voice coil 11 and the lower voice coil 12 are welded to the bracket.

[0042] The design method of a double-coil single-magnetic-circuit headphone speaker comprises the following steps:

[0043] S1. Calculate the axial vibration force F of the diaphragm 2 based on the following formula:

[0044] F=BLI(1)

[0045] Wherein, B is the magnetic induction intensity in the magnetic gap, in T; L is the effective length of the voice coil 1, in m; I is the current flowing through the voice coil 1, in A;

[0046] S2. Calculate the amplitude ξ of diaphragm 2:

[0047]

[0048] Where Pe represents electric power; η o represents the electroacoustic conversion efficiency, η o represents frequency; a represents equivalent radius;

[0049] The calculation formula of electroacoustic conversion efficiency is as follows:

[0050]

[0051] In the formula, ρ o represents the air density; c represents the speed of sound; BL represents the electric coupling coefficient, where B is the magnetic induction intensity in the magnetic gap, L is the effective length of the voice coil 1; S d Represents the equivalent radiation area; M ms represents the equivalent vibrating mass;

[0052] S3. Calculate the sound pressure level SPL:

[0053] SPL=112+10lgη o (4)

[0054] S4, substituting the set SPL value into formula (3) to solve the effective length L of the voice coil 1;

[0055] S5. Based on the effective length L of the voice coil 1 obtained in step S4, two coils are wound in parallel up and down (in this embodiment, two coils are wound in parallel up and down using a two-wire feeding machine), thereby obtaining the voice coil 1.

[0056] The voice coil 1 designed by the above method was tested with the traditional voice coil 1, and the results were as follows: Figure 5 As shown, it can be known that the improved voice coil 1 of the present invention improves the SPL value of the loudspeaker, thereby verifying the effectiveness of the present invention.

[0057] Therefore, the present invention adopts the above-mentioned double-coil single-magnetic circuit headphone speaker and its design method. Without increasing the size of the speaker, the voice coil is wound in parallel with upper and lower wires to increase the effective length of the voice coil wire, thereby improving the SPL value of the speaker.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A double-coil single-magnetic-circuit headphone speaker, comprising a diaphragm and a magnet arranged in sequence, wherein the edge of the diaphragm is arranged on a bracket, and a voice coil sleeved on the magnet is arranged on the side of the diaphragm facing the magnet, characterized in that: The voice coil is an integrated structure of upper and lower double-wire parallel windings, and the upper and lower double-wire parallel windings are both arranged concentrically with the magnet.

2. The double-coil single-magnetic-circuit headphone speaker according to claim 1, characterized in that: The upper and lower double-wire parallel winding integrated structure includes a lower voice coil and an upper voice coil connected in parallel. The lower voice coil and the upper voice coil are output in parallel to form two parallel circuits.

3. The double-coil single-magnetic-circuit headphone speaker according to claim 2, characterized in that: The upper voice coil and the lower voice coil are both made of enameled wire, and the output ends of the upper voice coil and the lower voice coil are welded to the bracket.

4. The design method of a double-coil single-magnetic-circuit headphone speaker according to claim 3, characterized in that: The following steps are involved: S1. Calculate the axial vibration force F of the diaphragm based on the following formula: F=BLI (1) Where, B is the magnetic induction intensity in the magnetic gap, in T; L is the effective length of the voice coil, in m; I is the current flowing through the voice coil, in A; S2. Calculate the amplitude ξ of the diaphragm: Where Pe represents electric power; η o represents the electroacoustic conversion efficiency, η o represents frequency; a represents equivalent radius; The calculation formula of electroacoustic conversion efficiency is as follows: In the formula, ρ o represents the air density; c represents the speed of sound; BL represents the electric coupling coefficient, where B is the magnetic induction intensity in the magnetic gap, L is the effective length of the voice coil; S d Represents the equivalent radiation area; M ms represents the equivalent vibrating mass; S3. Calculate the sound pressure level SPL: SPL=112+10lgη o (4) S4, substituting the set SPL value into formula (3) to solve the effective length L of the voice coil; S5. Based on the effective length L of the voice coil obtained in step S4, the upper and lower wires are wound in parallel as a whole, thereby obtaining a voice coil.

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