WO2021068623A1

WO2021068623A1 - Sound-producing apparatus and terminal device

Info

Publication number: WO2021068623A1
Application number: PCT/CN2020/106606
Authority: WO
Inventors: 林洲; 丁俊; 寇大贺
Original assignee: 华为技术有限公司
Priority date: 2019-10-11
Filing date: 2020-08-03
Publication date: 2021-04-15
Also published as: CN112653971B; CN112653971A

Abstract

Provided in the present application are a sound-producing apparatus and a terminal device, related to the technical field of electronic devices. The sound-producing apparatus mainly comprises a first magnetically permeable structure, a first magnetic element, a second magnetic element, a voice coil set, and a second magnetically permeable structure. The first magnetic element is connected to the first magnetically permeable structure to form a first vibrator. The voice coil set and the second magnetic element are connected to the second magnetically permeable structure to form a second vibrator. In addition, the voice coil set comprises at least two voice coils. Some voice coils of the at least two voice coils are parallel-connected in a one-to-one correspondence to one high-frequency short-circuiting element. In a high frequency state, the voice coils parallel-connected to the high-frequency short-circuiting element are short circuited so as to reduce the high-frequency resistance of the voice coil set, thus allowing a force generated in a changing magnetic field by the voice coil set into which an alternating current is introduced to meet the demand of the sound-producing apparatus for a vibration driving force, and favoring an improved sound-producing effect.

Description

Sounding device and terminal equipment

Cross-references to related applications

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on October 11, 2019, the application number is 201910962190.8, and the application name is "a sound generating device and terminal equipment", the entire content of which is incorporated into this application by reference .

Technical field

This application relates to the technical field of electronic equipment, and in particular to a sound generating device and terminal equipment.

Background technique

The sound comes from vibration, and the sound of most terminal equipment comes from the vibration of the sound generating device. At present, the mainstream sound device is a moving coil type or a moving iron type, and whether it is a moving coil or a moving iron type, the core principle is to use the Lorentz force generated by the energized coil in the magnetic field to drive the vibration of the sound device.

The energized coil is usually called a voice coil in the industry. The sound-generating device (speaker, vibration motor, etc.) generates Lorentz force through the voice coil energized in a magnetic field to drive the sound-generating device to emit sound. With the increasing requirements for the vibration driving capability of the sound generating device, increasing the number of turns of the voice coil is the most direct way to increase the driving force of the voice coil. However, the voice coil has a self-inductance effect. When the frequency of the alternating current passing through the voice coil is high, the self-inductance of the voice coil will generate a large induced current, so that the impedance of the voice coil increases rapidly with the increase of the angular frequency. Rising, so as to cause the high-frequency frequency response amplitude of the sounding device to decrease, which in turn affects the sounding effect of the sounding device.

Summary of the invention

The technical solution of the present application provides a sounding device and terminal equipment to enhance the high frequency response of the sounding device and improve the sounding effect of the terminal equipment.

In the first aspect, the technical solution of the present application provides a sound generating device, which mainly includes a first vibrating body and a second vibrating body, wherein the first vibrating body is formed by connecting a first magnetic element and a first magnetically conductive structure, The second vibrating body is mainly formed by connecting the second magnetic element and the second magnetic conductive structure. The second magnetic element is arranged on the side of the second magnetically permeable structure close to the first magnetic element, and the first magnetic element and the second magnetic element repel, so that the first vibrating body and the second vibrating body are kept at a set distance Stable, and no adsorption occurs during vibration. In addition, the sound emitting device further includes a voice coil group, which is sleeved on the second magnetic element and fixed to the second magnetically permeable structure. The voice coil group includes at least two voice coils connected in series, and part of the voice coils of the at least two voice coils connected in series are connected in parallel with a high-frequency short-circuit element in parallel. When the frequency of the AC signal applied to the voice coil group is When it is the set value, the high-frequency short-circuit element makes the parallel-connected voice coils in a short-circuit state.

By setting the voice coil group as a multi-segment voice coil in series, and connecting some of the voice coils in parallel with high-frequency short-circuit elements to make this part of the voice coil work in the high frequency band, the voice coil is short-circuited by its parallel high-frequency short-circuit elements, that is Produce a high-frequency short-circuit effect, which can reduce the impedance of this part of the voice coil, thereby reducing the high-frequency impedance of the voice coil group, so that the force generated by the voice coil group with alternating current in the changing magnetic field can meet the requirements of the sound device The vibration driving force is required to be able to produce better vibration effects, improve the high-frequency frequency response of the sound device, and help improve its sound effect.

In the second aspect, the technical solution of the present application also provides a terminal device, which includes a display screen, a middle frame, a rear shell, and the sound emitting device of the first aspect, wherein the display screen and the rear shell are separately provided on both sides of the middle frame , The sound device is set between the display screen and the middle frame. The middle frame can be used to carry the display screen and the sounding device. The first vibrating body of the sounding device is fixed to the display screen, and the second vibrating body is fixed to the middle frame.

In this embodiment, the high-frequency frequency response of the vibration device of the terminal device is improved, and at the same time, the low-frequency frequency response performance can be maintained without degradation. In addition, after the impedance is reduced, the impedance matching condition of the voice coil group of the terminal equipment and the impedance of the power amplifier is improved, which is beneficial to improve the working efficiency of the power amplifier at high frequencies. In addition, because the force generated by the voice coil group with alternating current in the changing magnetic field can meet the requirements of the vibration driving force of the sound device, this can produce greater vibration displacement, so that the terminal device can produce better sound effects. .

Description of the drawings

Fig. 1 is a schematic diagram of the force exerted by the voice coil in a magnetic field according to an embodiment of the application;

FIG. 2 is a schematic structural diagram of a terminal device provided by an embodiment of this application;

Figure 3 is a cross-sectional view of A-A in Figure 2;

Figure 4 is a cross-sectional view of A-A in Figure 2;

Fig. 5 is a schematic diagram of an exploded structure of a sound emitting device according to an embodiment of the application;

6 is a schematic diagram of the structure of the sound generating device in an assembled state according to an embodiment of the application;

Figure 7 is a cross-sectional view of C-C in Figure 6;

Figure 8 is a cross-sectional view of C-C in Figure 6;

FIG. 9 is a schematic diagram of an equivalent structure of a voice coil group according to an embodiment of the application;

FIG. 10 is a schematic diagram of an equivalent structure of a voice coil group according to another embodiment of the application;

Fig. 11 is an equivalent circuit of a passive second-order high-pass voice coil according to an embodiment of the application;

FIG. 12 is an equivalent circuit of an active second-order high-pass voice coil according to an embodiment of the application;

FIG. 13 is an impedance curve diagram of a simulation result of an embodiment of the application;

FIG. 14 is a frequency response curve diagram of a simulation result of an embodiment of the application;

FIG. 15 is a schematic diagram of a setting method of a voice coil group according to an embodiment of the application;

FIG. 16 is a schematic diagram of a setting method of a voice coil group according to another embodiment of the application;

FIG. 17 is a schematic diagram of a setting method of a voice coil group according to another embodiment of the application;

FIG. 18 is a frequency response curve diagram of a voice coil group simulation result according to another embodiment of the application;

FIG. 19 is a frequency response curve diagram of a voice coil group simulation result according to another embodiment of the application;

FIG. 20 is a schematic structural diagram of a sound emitting device according to another embodiment of the application.

Reference signs:

1-coil; 10-terminal equipment; 101-sounding device; 102-display; 103-middle frame; 104-rear shell;

105-protective cover plate; 1011-first magnetic conductive structure; 10111-first accommodating groove; 1012-first magnetic element;

1013-Second magnetic element; 1014-Voice coil group; 1014A-First voice coil; 1014B-Second voice coil;

1014C-third voice coil; 10141-capacitive element; 10142-passive second-order high-pass filter circuit;

10143-Active second-order high-pass filter circuit; 1015-Second magnetic structure; 10151-Second accommodating slot;

1016-first vibrating body; 1017-second vibrating body; 201-housing; 202-third magnetic element;

203-third magnetically permeable structure; 204-diaphragm; 205-support structure; 206-third accommodating groove.

Detailed ways

In order to facilitate the understanding of the sound emitting device provided by the embodiments of this application, the following first describes the application scenarios of the sound emitting device provided by the embodiments of this application. The sound emitting device can be installed in terminals such as mobile phones, tablets, and handheld computers (personal digital assistants, PDAs). In the equipment, in the present application, taking the sound emitting device installed in a mobile phone as an example, the sound emitting device and the terminal equipment provided with the sound emitting device will be described in detail.

The screen sounding technology using magnetic suspension arrays can be achieved by dividing the sounding device into two parts, one of which is attached to the display screen, and the other part is fixed to structural parts such as the middle frame. The part of the sounding device fixed on the middle frame and other structural parts is provided with a coil. In this way, referring to Figure 1, the coil 1 (also called the voice coil) can be placed in a magnetic field (magnetic field strength is B), and the coil 1 An alternating current signal is applied to make the current flowing in the coil 1 an alternating current, thereby generating a Lorentz force F that repeats back and forth on the coil 1. According to the force and reaction force of the third law of mechanics, the force generated on the coil 1 through the change of the magnetic field can act on the part of the sounding device attached to the display screen, so that the part of the sounding device can be driven to vibrate. Drive the display to vibrate and make a sound. This kind of vibration principle, because it can produce larger vibration displacement, can produce better vibration effect, and has a better application prospect.

Referring to FIG. 2, in an embodiment of the present application, according to the specific structure of the terminal device 10, the sounding device 101 can be installed in any position of the terminal device 10. For example, continuing to refer to FIG. 2, the sounding device 101 can be installed in the terminal device 10. The middle and upper part of the whole structure of the device is adapted to the user's habits of using the terminal device 10 in situations such as making and receiving calls.

In order to further understand the setting position and setting method of the sound emitting device 101 in the terminal device 10, refer to FIG. 3, which is a schematic diagram of the layer structure of the terminal device 10. Among them, the terminal device 10 may include a display screen 102, a middle frame 103, a rear case 104, and a sounding device 101. The display screen 102 and the rear case 104 are separately arranged on both sides of the middle frame 103, and the sounding device 101 is arranged on the display screen 102 and the middle frame. Between 103. The middle frame 103 can be used to carry the display screen 102 and the sound device 101, and the sound device 101 can be connected to the display screen 102. During the vibration process of the sound generating device 101, the display screen 102 will be driven to vibrate and produce sound, so that a greater vibration displacement can be generated, so that the terminal device 10 can produce a better sound effect.

In addition, the terminal device 10 may further include a protective cover 105 covering the display screen 102. The protective cover 105 may be a glass cover, so as to protect the display screen 102 and reduce the impact on the display screen 102. 102's display effect.

In another possible embodiment of the present application, referring to FIG. 4, a terminal device 10 is also provided. The terminal device 10 may include a display screen 102, a middle frame 103, a rear case 104, and a sounding device 101. The rear shell 104 is separately arranged on both sides of the middle frame 103, and the sound generating device 101 is arranged between the rear shell 104 and the middle frame 103. The middle frame 103 can be used to carry the display screen 102 and the sounding device 101, and the sounding device 101 can be connected to the rear case 104. During the vibration process of the sound generating device, the rear shell 104 will be driven to vibrate and produce sound, which can generate greater vibration displacement, so that the terminal device 10 can produce a better sound effect to meet the sound output requirements of the terminal device 10.

In the process of applying the above-mentioned vibration principle, when a current flows through the voice coil, an induced electromagnetic field will be formed in the voice coil, and the induced electromagnetic field will generate an induced current in the voice coil to resist the current passing through the voice coil. The interaction between this current and the voice coil is called the inductance of the voice coil, which is the inductance in the circuit. Therefore, ignoring the mechanical loss damping and radiation damping, the AC impedance of the voice coil can be described as Ze=Re+j*w*Le, where Re is the DC resistance of the voice coil, w is the angular frequency of the AC signal, and Le is Voice coil inductance, j is an imaginary number sign.

When w=0, the total impedance of the voice coil is equal to the DC resistance of the voice coil, and then as the frequency increases, the total impedance continues to rise.

With the increasing requirements for the driving capability of the sound-generating device, increasing the number of turns of the voice coil is the most direct way to increase the driving force of the voice coil. However, the inductance of the voice coil is more complicated, and its impedance is usually obtained by testing, but it can also be estimated by the empirical formula: Le=(k*μ0*μs*N^2*S)/L, k is the coefficient, which depends on For the ratio of the radius r of the voice coil to the length L, μ0 is the vacuum permeability, μs is the relative permeability of the inner core of the voice coil, when the hollow voice coil is μs=1, N is the number of turns of the voice coil, and S is the sound The cross-sectional area of the coil, L is the length of the voice coil.

It can be seen from the above formula that the inductance of the voice coil is proportional to the square of the number of turns of the voice coil, that is, the inductance of the voice coil increases as the square of the number of turns increases, and a high number of turns will bring about a serious effect of high inductance.

In order to solve the above problem, referring to FIG. 5, an embodiment of the present application provides a sound emitting device, which mainly includes a first magnetically permeable structure 1011, a first magnetic element 1012, a second magnetic element 1013, a voice coil group 1014, and a first magnetic element 1012. Two magnetic structure 1015. Among them, the first magnetic element 1012 and the second magnetic element 1013 can be, but are not limited to, a magnet or a circuit capable of generating magnetism. In this application, devices that can generate a magnetic field or have magnetism are referred to as magnetic elements; The specific materials of the magnetic structure 1011 and the second magnetically permeable structure 1015 are not limited, and high-permeability materials can be selected as far as possible according to specific conditions.

6 and 7 together, the first magnetically permeable structure 1011 has a first accommodating groove 10111, the first magnetic element 1012 is accommodated in the first accommodating groove 10111, and is adsorbed on the first magnetically permeable structure 1011 The inner side wall forms the first vibrating body 1016 of the sound device 101; the voice coil group 1014 is sleeved on the second magnetic element 1013, the second magnetically conductive structure 1015 has a second accommodating groove 10151, the voice coil group 1014, and the second magnetic element 1013. The magnetic element 1013 is accommodated in the second accommodating groove 10151 and is fixedly connected to the second magnetic conductive structure 1015 to form the second vibrating body 1017 of the sound device 101. Wherein, the voice coil assembly 1014 can be adhered to the inner side wall of the second magnetic conductive structure 1015 through an adhesive such as adhesive glue. In addition, according to the principle of repulsion of the same sex between two magnetic elements and attraction of the opposite sex, the polarities of the two adjacent ends of the first magnetic element 1012 and the second magnetic element 1013 can be the same. In addition, the projection of the second magnetic element 1013 on the first magnetically permeable structure 1011 can also be made to fall within the projection of the first magnetic element 1012 on the first magnetically permeable structure 1011, so that the first magnetic element 1012 and The second magnetic elements 1013 repel each other, and the first magnetic element 1012 and the first magnetically permeable structure 1011 are attracted to each other, so that the first vibrating body 1016 and the second vibrating body 1017 can have a relatively stable setting. At the same time, the two will not be adsorbed during the vibration process. In the process of applying current to the voice coil group 1014, a repeated Lorentz force is generated on the voice coil group 1014, which makes the second vibrating body 1017 immobile. Therefore, according to Newton’s third law, the force is the same as According to the principle of reaction force, the reaction force of the second vibrating body 1017 will act on the first vibrating body 1016 to drive the first vibrating body 1016 to vibrate.

Wherein, when the voice coil group 1014 is specifically set, the voice coil group 1014 includes at least two voice coils. Referring to FIG. 7, in FIG. 7, the voice coil group 1014 includes a first voice coil 1014A and a second voice coil 1014B as For example, the structure of the voice coil group 1014 will be described. Wherein, the first voice coil 1014A and the second voice coil 1014B can be coaxially arranged, and they are arranged on top of each other along the axial direction of the two voice coils; or, referring to FIG. 8, the first voice coil 1014A and the second voice coil 1014A can also be arranged on top of each other. The voice coil 1014B is sleeved along the radial direction of the two voice coils.

In addition, referring to FIG. 9, FIG. 9 is an equivalent diagram of the connection of at least two voice coils of the voice coil group 1014 of the sound emitting device. It can be seen from FIG. 9 that some of the at least two voice coils of the voice coil group 1014 are connected with high-frequency short-circuit elements in parallel. When the frequency of the AC signal applied to the voice coil is the set value, the high-frequency short-circuit The element makes the parallel voice coils in a short-circuit state. The high-frequency short-circuit element may be a capacitive element 10141, or a circuit that can realize a high-frequency short-circuit effect; the other part of the voice coils in at least two voice coils of the voice coil group 1014 is not connected in parallel High-frequency short-circuit components. When the high-frequency short-circuit element is a capacitive element 10141, the capacitance of the capacitive element 10141 is estimated by (1/(k*Re2)-1/Ze2)/(j*2*pi*freq), where k is a coefficient, It can be selected from 0.01 to 0.5 according to the degree of impedance rise; Re is the DC impedance of the voice coil 1014B with the capacitive element 10141 in parallel, Ze is the AC impedance of the voice coil 1014B with the capacitive element 10141 in parallel, and freq is Ze The frequency of the AC signal applied to the voice coil 1014B in the interval of >Re. For ease of description, the following takes the high-frequency short-circuit element as the capacitive element 10141 as an example for description.

Specifically, continuing to refer to FIG. 9, when the voice coil group 1014 of the sound generating device includes two voice coils, the first voice coil 1014A and the second voice coil 1014B, the first voice coil 1014A and the second voice coil 1014B are arranged in series, and The second voice coil 1014B is connected with a capacitor element 10141 in parallel, and the first voice coil 1014A is not connected in parallel with a capacitor element. In some embodiments of the present application, the first voice coil 1014A may be connected with a capacitor element in parallel, and the second voice coil 1014B is not connected in parallel. Parallel capacitive element. As shown in FIG. 10, when the voice coil group 1014 includes more than two voice coils, for example, the first voice coil 1014A, the second voice coil 1014B, and the third voice coil 1014C three voice coils, the first voice coil 1014A does not have capacitors connected in parallel so that it can always be in working condition. The second voice coil 1014B and the third voice coil 1014C each have a capacitor in parallel. Of course, one of the second voice coil 1014B or the third voice coil 1014C can also be used. Capacitive elements are connected in parallel.

Since the original inductance of the voice coil with N turns is Le, Le is proportional to the square of the voice coil turns (N^2), Le=(k*μ0*μs*N^2*S)/L, abbreviated Is B*N^2/L;

The impedance expression of the voice coil is Ze=Re+j*w*Le;

Taking the split of a single voice coil with N turns into a voice coil group including two voice coils as an example, the impedance of the voice coil group at this time can be expressed as:

Ze=Re1+j*w*Le1+Re2+j*w*Le2;

At this time, the impedance after a capacitor is connected in parallel to the second voice coil can be expressed as:

Ze′=Re1+j*w*Le1+1/(1/(Re2+j*w*Le2)+j*w*C);

When the angular frequency w increases, the impedance of the second voice coil connected in parallel with the capacitor decreases;

The impedance of the first voice coil is Ze1=Re1+j*w*Le1, when the number of turns of the two voice coils is the same, the value of Le1 is proportional to B*(N/2)^2/(L/2), As the effective number of turns decreases, the value of Le1 also drops greatly, so that the impedance of the first voice coil does not rise significantly. Therefore, in a high frequency scenario, compared with a single voice coil with N turns, the impedance of a voice coil group including two voice coils (the total number of turns of the two voice coils is N) is greatly reduced.

From the above derivation, it can be concluded that by setting the voice coil group as a multi-segment voice coil in series, and connecting some of the voice coils in parallel with capacitive elements, so that when this part of the voice coil works in the high frequency band, the voice coil is connected in parallel by the capacitor The short circuit of the component produces a high-frequency short-circuit effect, which can reduce the impedance of this part of the voice coil, thereby reducing the high-frequency impedance of the voice coil group, so that the force generated by the voice coil group with alternating current in the changing magnetic field can be The requirement of the driving force of the sound generating device is met to be able to generate a better vibration effect, and the high frequency response of the sound generating device is improved, which is beneficial to improve the sound generating effect.

Similarly, when the high-frequency short-circuit element is a circuit that can realize the high-frequency short-circuit effect, the equivalent diagrams of the connection of at least two voice coils of the voice coil group 1014 of the sound generating device can refer to FIGS. 11 and 12. Among them, Figure 11 is the passive second-order high-pass voice coil equivalent circuit, in which the second voice coil 1014B is connected in parallel with a passive second-order high-pass filter circuit 10142. When the second voice coil 1014B works in the high frequency band, the passive second-order The high-pass filter circuit 10142 passes the high-frequency current signal, so that the second voice coil 1014B is short-circuited. In addition, referring to Figure 12, Figure 12 is an active second-order high-pass voice coil equivalent circuit, in which the second voice coil 1014B is connected in parallel with an active second-order high-pass filter circuit 10143. When the second voice coil 1014B works in a high frequency band, The active second-order high-pass filter circuit 10143 passes the high-frequency current signal, so that the second voice coil 1014B is short-circuited. In order to reduce the impedance of the second voice coil 1014B, the high frequency impedance of the voice coil group 1014 is reduced.

In order to facilitate a further understanding of the high-frequency impedance and improvement of the high-frequency frequency response of the sound generating device of the present application, a sound generating device including a voice coil group with two voice coils in series, and a single voice coil (the total number of turns of a single voice coil is The total number of turns of the voice coil group with two voice coils connected in series is the same) the high-frequency impedance and high-frequency frequency response of the sound generating device are compared. Specifically, the number of voice coil turns of a single-voice-coil sounding device is 200 turns; in a sounding device with two voice coils in series, the number of turns of the two voice coils is 100 turns respectively, and one of the voice coils is connected to one of the voice coils. Connect a capacitive element in parallel. Among them, since the capacitance value of the capacitive element C=(1/(k*Re)-1/Ze)/(j*2*pi*freq), let Re=4ohm, freq=2kHz, and Ze is the measured segment The impedance of the circle at 2kHz, k=0.2, and the capacitance value of the capacitive element is calculated to be 100uF.

Referring to Figure 13, Figure 13 shows the impedance curve of a single voice coil with a total number of 200 turns (solid line in Figure 13), and the impedance curve of a voice coil group including a double voice coil with a number of turns of 100+100 (Figure The dotted line in 13). The analysis shows that, relative to a single voice coil with 200 turns, the impedance of a dual voice coil group with two voice coils in series (a 100uF capacitor is connected in parallel to one of the voice coils) increases with frequency It is slower and the rising amplitude is small, and the impedance of the voice coil group rises with the frequency has been effectively improved.

In addition, referring to Figure 14, Figure 14 shows the frequency response curve of a single voice coil with 200 turns (the solid line in Figure 14), and the frequency response of a voice coil group including a double voice coil with 100+100 turns. Curve (dotted line in Figure 14). Among them, the double voice coil voice coil group with two voice coils in series (one of the voice coils is connected in parallel with a 100uF capacitor) has a significant improvement in high frequency frequency response (simulation results prove that when the frequency is 10kHz, the frequency response is about Increased by 3dB, when the frequency is 20kHz, the frequency response is increased by about 6dB).

It is understandable that the foregoing is only an exemplary description of the manner of setting the voice coil group of the sound emitting device of the present application. In some possible embodiments of the present application, taking the total number of turns of the voice coil group as an example, the number of turns of two voice coils connected in series can also be set to a combination of 120 turns+80 turns, etc. respectively. In addition, if a combination of different wires is used, the distribution of the number of turns can be more flexible, and the total number of turns can also be changed.

In some embodiments of the present application, since the magnetic field intensity distribution of each spatial region in the sound emitting device is not uniform, in this way, at least two voice coils of the voice coil group of the sound emitting device can be determined according to the magnetic field of the space in which they are located. Set the number of turns of each voice coil.

When setting the voice coil group specifically according to the magnetic field strength, still take the voice coil group including two voice coils connected in series as an example. Fig. 15 shows a setting method of two voice coils. The first voice coil 1014A is set at In the region where the magnetic field strength is relatively large, the second voice coil 1014B is provided in the region where the magnetic field strength is relatively small on the peripheral side of the first voice coil 1014A.

In addition, in addition to the arrangement of FIG. 15 described above, referring to FIG. 16, the two voice coils can also be arranged side by side, or arranged in a stacked manner with reference to FIG. 17 to simplify the arrangement of the two voice coils.

Because, when the voice coil is in a magnetic gap with a magnetic field strength of B and the current passing through the voice coil is I, according to the left-hand rule, the voice coil will receive an electromotive force F=B*L*I, and L is the total length of the voice coil .

15-17, because the spatial magnetic field distribution is not uniform, take the voice coil group 1014 including the first voice coil 1014A and the second voice coil 1014B as an example, assuming the space where the first voice coil 1014A is located The average magnetic field strength of B1=1.2*B, and the average magnetic field strength of the space where the second voice coil 1014B is located is B2=0.8*B.

When the number of turns of the two voice coils is equal, for example 100 turns, the force of the voice coil group 1014 is:

F=1.2*B*L/2*I+0.8*B*L/2*I=B*L*I;

Using the non-uniform distribution scheme, referring to the arrangement of the voice coil group 1014 in FIG. 17, taking 150 turns at the

first voice coil

1014A and 50 turns at the second voice coil 1014B as an example, the force of the voice coil group 1014 for:

F′=1.2*B*150/100*L/2*I+0.8*B*50/100*L/2*I=1.1*B*L*I;

It can be seen from the above-mentioned before and after comparison that according to the distribution of the magnetic field strength, the first voice coil 1014A with more turns (150 turns) is used in the area with strong magnetic field strength, and the number of turns is set in the area with weak magnetic field strength. With a few (50 turns) second voice coil 1014B, such a solution that the number of turns is non-uniformly distributed, the force of the voice coil group 1014 can be increased by 10%. It is understandable that when the non-uniformity of the magnetic field distribution is more obvious, the force of the voice coil group 1014 can be increased more. Therefore, setting the ratio of the number of turns of the first voice coil 1014A and the second voice coil 1014B according to the intensity of the magnetic field can increase the force of the voice coil group 1014, thereby effectively improving the utilization rate of the magnetic field.

It is understandable that the foregoing are only some exemplary descriptions of the arrangement of the voice coil set 1014 given in the embodiments of the present application. The voice coil with a larger number of turns is arranged in a region with a larger magnetic field strength, and a voice coil with a smaller magnetic field strength is provided. Based on the theoretical basis of regional setting of voice coils with fewer turns, the setting of each voice coil can be adjusted adaptively. In addition, if a combination of different wires is used, the distribution of the number of turns can be more flexible, and the total number of turns can also be changed.

In addition, when the two voice coils are arranged in the stacking manner in FIG. 17, and the number of turns of the first voice coil 1014A is 150 turns, and the number of turns of the second voice coil 1014B is 50 turns as an example, The frequency response curve obtained by the simulation of the circle group 1014 can refer to FIG. 18. In Figure 18, the dashed line represents the frequency response curve of the voice coil group with the same number of turns of the two voice coils (for ease of description, hereinafter referred to as the first voice coil group); the solid line represents the frequency response curve according to the strength of the magnetic field. The frequency response curve of the voice coil group (for ease of description, hereinafter referred to as the second voice coil group) is the principle of setting a voice coil with a large number of turns in a space with a weak magnetic field strength and a voice coil with a small number of turns in a space with weak magnetic field strength. Among them, the total number of turns of the two voice coil groups is the same. It can be seen from Fig. 18 that, compared with the first voice coil group, the second voice coil group provides a voice coil with a larger number of turns in a space with a strong magnetic field, and a space with a weak magnetic field with a smaller number of turns. It can improve the frequency response of the second voice coil group in the full frequency range.

In this embodiment of the present application, under the condition that the total number of turns remains unchanged, the number of voice coil turns is increased in the part with strong magnetic field strength, and the number of voice coil turns is reduced in the part with weak magnetic field strength, so that the force of the voice coil group can be satisfied. It is required to improve the utilization rate of the magnetic field and enhance the frequency response of the full frequency band of the voice coil group.

In another embodiment of the present application, a sounding device is also provided. In combination with the foregoing embodiments, in the sounding device, the voice coil group includes at least two voice coils connected in series. When the voice coil group is specifically set, some of the voice coils in the voice coil group are connected in parallel with capacitive elements, and the other part of the voice coil is not connected in parallel with capacitive elements. The capacitance of the parallel capacitive elements is determined by (1/(k*Re2)- 1/Ze2)/(j*2*pi*freq) estimate, where k is a coefficient, which can be selected from 0.01 to 0.5 according to the degree of impedance rise; Re is a voice coil 1014B with a capacitor element 10141 in parallel Ze is the AC impedance of the voice coil 1014B with the capacitive element 10141 in parallel, and freq is the frequency of the AC signal applied to the voice coil 1014B in the range of Ze>Re.

In addition, because the magnetic field intensity distribution in the internal space of the sounding device is not uniform, the voice coil with more turns in the voice coil group can be placed in the magnetic field with stronger magnetic field strength, and the sound with fewer turns can be placed in the magnetic field. The circle is arranged in a magnetic field with a weaker magnetic field strength.

Referring to Fig. 19, Fig. 19 shows a simulated frequency response curve of a voice coil group in which two voice coils are connected in series and the two voice coils have different combinations of turns. Among them, in Figure 19, the frequency response curve of a 200-turn single voice coil, the frequency response curve of a voice coil group of 100 turns + 100 turns, and the frequency response curve of a voice coil group of 120 turns + 80 turns are respectively given in different line types. Response curve (a 120-turn coil is set in a weak magnetic field, and a 80-turn coil is set in a strong magnetic field), 80 turns + 120 turns (a 80-turn coil is set in a weak magnetic field, and 120 is set in a strong magnetic field. The frequency response curve of the voice coil group, and the frequency response curve of the voice coil group of 60+140 turns (the space with weak magnetic field strength is set with 60 turns, the space with strong magnetic field strength is set with 140 turns) .

Through the analysis of the simulated frequency response curve of the voice coil group in each combination state in Figure 19, it can be concluded that when the total number of turns is the same, two (or more) voice coils in series are used to replace the original single tone. Coil design, and connect a capacitive element in parallel with one (or more) voice coils (or circuit design to achieve high-frequency short-circuit effect) to make it produce high-frequency short-circuit effect, thereby improving the high-turn voice coil scenario The problem of high-frequency impedance increase too fast, improves the high-frequency frequency response of the sound device, while maintaining the low-frequency frequency response performance without degradation. In addition, after the impedance is reduced, the impedance matching condition of the voice coil group and the power amplifier is improved, which is beneficial to improve the working efficiency of the power amplifier at high frequencies.

According to the distribution of the magnetic field intensity of the magnetic circuit system, the number of turns of the voice coil is arranged in different regions. Specifically, a thin wire is used to form a high-turn voice coil at a high-intensity magnetic field, and a thick wire is used to form a low-turn voice coil at a low-intensity magnetic field. Voice coil. In this way, the utilization rate of the magnetic field can be improved while meeting the force requirements of the voice coil group, thereby bringing about an improvement in the frequency response of the entire frequency band.

Referring to FIG. 20, in another embodiment of the present application, a sound generating device is also provided, which includes a housing 201, a third magnetic element 202, a third magnetic conductive structure 203, a voice coil group 1014, and a diaphragm 204 , Wherein the housing 201 includes a third accommodating groove 206, the third magnetic element 202, the third magnetic structure 203, and the voice coil group 1014 are accommodated in the third accommodating groove 206, and the third magnetic element 202 is adsorbed on the The bottom wall of the three accommodating grooves 206, and the third magnetic conductive structure 203 is disposed on a side of the third magnetic element 202 away from the bottom wall of the third accommodating groove 206. The voice coil set 1014 includes at least two voice coils connected in series, and some of the voice coils of the at least two voice coils are connected in parallel with a capacitive element (not shown in the figure, refer to FIG. 9 or FIG. 10). , The capacitance of the parallel capacitive element is estimated by (1/(k*Re2)-1/Ze2)/(j*2*pi*freq), where k is a coefficient, which can be between 0.01 and 0.5 according to the impedance The degree of rise is taken; Re is the DC impedance of the voice coil with capacitive elements in parallel, Ze is the AC impedance of the voice coil with capacitive elements in parallel, freq is the AC signal applied to the voice coil in the range of Ze>Re frequency. Another part of the voice coil is not connected in parallel with capacitive elements so as to be able to always be in working condition. In addition, the voice coil group 1014 is sleeved on the third magnetic structure 203 and the third magnetic element 202, and the voice coil group 1014 is fixed to the diaphragm 204. The diaphragm 204 covers the casing 201 and is fixed to the supporting structure 205 on the outer peripheral side of the casing 201.

In addition, when the voice coil group 1014 is specifically set, since the magnetic field intensity distribution in the internal space of the sounding device is not uniform, the voice coil with more turns in the voice coil group can be installed in the magnetic field space with stronger magnetic field intensity. Inside, a voice coil with a smaller number of turns is placed in a magnetic field with a weaker magnetic field.

In this embodiment of the present application, by connecting a capacitive element in parallel with one (or more) voice coils of the voice coil group 1014 (or a circuit design that realizes the high-frequency short-circuit effect), the other part of the voice coil is not connected in parallel with a capacitive element , In order to produce a high-frequency short-circuit effect at the voice coil with capacitive elements in parallel, thereby improving the problem of too fast high-frequency impedance increase in the high-turn voice coil scene, improving the high-frequency frequency response of the sound device, and at the same time Keep the low frequency frequency response performance not degraded. In addition, after reducing the impedance, the impedance matching condition of the voice coil group and the power amplifier is improved, which is beneficial to improve the working efficiency of the power amplifier at high frequencies.

In an embodiment of the present application, a speaker is also provided, and the speaker includes the sound emitting device of the foregoing embodiment. The loudspeaker's high-frequency frequency response has been improved, while maintaining the low-frequency frequency response performance without degradation. In addition, after the impedance is reduced, the impedance matching condition of the speaker's voice coil group and the impedance of the power amplifier is improved, which is conducive to improving the working efficiency of the power amplifier at high frequencies. In addition, since the sound generating device of the loudspeaker can increase the utilization rate of the magnetic field while meeting the force requirement of the voice coil group, thereby bringing about an improvement in the frequency response of the whole frequency range, the sounding effect of the loudspeaker is better.

[Examples]

1. A sound emitting device, characterized by comprising a first magnetically permeable structure, a first magnetic element, a second magnetic element, a voice coil group, and a second magnetically permeable structure, wherein:

The first magnetic element is connected with the first magnetically conductive structure to form a first vibrating body of the sound generating device;

The second magnetic element is arranged on a side of the second magnetic conductive structure close to the first magnetic element, and the voice coil assembly is sleeved on the second magnetic element and fixed to the second magnetic element to form The second vibrating body of the sound generating device; the first magnetic element and the second magnetic element repel, so that there is a set distance between the first vibrating body and the second vibrating body;

The voice coil set includes at least two voice coils connected in series, and part of the voice coils of the at least two voice coils connected in series are connected in parallel with a high-frequency short-circuit element. When the frequency of the AC signal of the group is the set value, the high-frequency short-circuit element causes the parallel-connected voice coils to be in a short-circuit state.

2. The sounding device of embodiment 1, wherein the high-frequency short-circuit element is a capacitive element, and the capacitance value of the capacitive element C=(1/(k*Re2)-1/Ze2)/( j*2*pi*freq), k is the coefficient, Re is the DC impedance of the voice coil with capacitive elements in parallel, Ze is the AC impedance of the voice coil with the capacitive elements in parallel, freq is the interval of Ze>Re The frequency of the AC signal applied to the voice coil within the range.

3. The sound device according to embodiment 2 or 3, wherein the first magnetically conductive structure has a first accommodating groove, and the first magnetic element is accommodated in the first accommodating groove.

4. The sound generating device according to any one of embodiments 1 to 3, wherein the second magnetically conductive structure has a second accommodating groove, and the voice coil group and the second magnetic element are accommodated in The second accommodating groove.

5. The sound generating device according to any one of embodiments 1 to 4, wherein the projection of the second magnetic element on the first magnetically permeable structure falls on the first magnetic element on the Within the projection on the first magnetically permeable structure.

6. The sound generating device according to any one of embodiments 1 to 5, wherein the first magnetic element is a magnet or a circuit structure that generates magnetism; and/or, the second magnetic element is a magnet or a circuit structure that generates magnetism; Magnetic circuit structure.

7. The sound generating device according to any one of embodiments 1 to 6, wherein the at least two voice coils connected in series are arranged coaxially, and overlapped along the axis of the at least two voice coils. .

8. The sound generating device according to any one of embodiments 1 to 6, wherein the at least two voice coils connected in series are coaxially arranged and nested along the radial direction of the at least two voice coils. Assume.

9. The sound generating device according to any one of embodiments 1 to 8, wherein the number of turns of the at least two voice coils connected in series is the same.

10. The sound generating device according to any one of embodiments 1-9, wherein the sound generating device has a first magnetic field space and a second magnetic field space, and the magnetic field strength of the first magnetic field space is greater than that of the second magnetic field space. Magnetic field strength in magnetic space;

The voice coil group includes a first voice coil and a second voice coil, the number of turns of the first voice coil is equal to the number of turns of the second voice coil, and the second voice coil is connected in parallel with a capacitive element; A voice coil is arranged in the first magnetic field space, and the second voice coil is arranged in the second magnetic field space.

11. The sound generating device according to any one of embodiments 1 to 9, wherein the sound generating device has a first magnetic field space and a second magnetic field space, and the magnetic field strength of the first magnetic field space is greater than that of the second magnetic field space. Magnetic field strength in magnetic space;

The voice coil set includes a first voice coil and a second voice coil, the number of turns of the first voice coil is greater than the number of turns of the second voice coil, and the first voice coil is disposed in the first magnetic field space Inside, the second voice coil is arranged in the second magnetic field space.

12. The sound generating device of embodiment 11, wherein the second voice coil is connected with a capacitive element in parallel.

13. A terminal device, characterized by comprising a display screen, a middle frame, a rear case, and the sounding device according to any one of embodiments 1 to 12, wherein:

The display screen and the rear case are separately arranged on both sides of the middle frame, the sound generating device is arranged between the display screen and the middle frame, and the middle frame is used to carry the display screen and the middle frame. The sounding device;

The first vibrating body of the sound generating device is fixed to the display screen, and the second vibrating body is fixed to the middle frame.

14. The terminal device of embodiment 13, wherein the terminal device may further include a protective cover plate covering the display screen.

15. A terminal device, characterized by comprising a display screen, a middle frame, a rear case, and the sounding device according to any one of embodiments 1 to 12, wherein:

The display screen and the rear shell are separately arranged on both sides of the middle frame, the sound generating device is arranged between the rear shell and the middle frame, and the middle frame is used to carry the display screen and the middle frame. The sounding device;

The first vibrating body of the sound generating device is fixed to the rear case, and the second vibrating body is fixed to the middle frame.

16. A sound generating device, characterized by comprising a housing, a third magnetic element, a third magnetically permeable structure, a voice coil group and a diaphragm, wherein:

The housing includes a third accommodating groove, and the third magnetic element, the third magnetically conductive structure, and the voice coil group are accommodated in the third accommodating groove;

The third magnetic element is adsorbed on the bottom wall of the third accommodating groove, and the third magnetically conductive structure is arranged on a side of the third magnetic element away from the bottom wall of the third accommodating groove;

The voice coil group is fixed to the diaphragm, the diaphragm includes at least two voice coils connected in series, and a capacitor is connected in parallel to some of the at least two voice coils in series. Element, the capacitance value of the capacitive element C=(1/(k*Re2)-1/Ze2)/(j*2*pi*freq), k is the coefficient, and Re is the direct current of the voice coil connected with the capacitive element in parallel Impedance, Ze is the AC impedance of the voice coil with the capacitive element in parallel, and freq is the frequency of the AC signal applied to the voice coil in the range of Ze>Re;

The diaphragm covers the casing and is fixed on the peripheral side of the casing.

17. The sound device of embodiment 16, wherein a support structure is further provided on the peripheral side of the housing, and the diaphragm is fixed to the support structure.

18. A loudspeaker characterized by comprising the sound emitting device as described in embodiment 16 or 17.

19. A sounding device, characterized by comprising a plurality of voice coils, some of the voice coils are connected in parallel with high-frequency short-circuit elements, and other voice coils are not connected in parallel with the high-frequency short-circuit elements. The short-circuit element makes the part of the voice coil connected in parallel with the high-frequency band of the audio to be in a short-circuit state.

20. The sound generating device of embodiment 20, wherein the high frequency band is greater than or equal to 1000 Hz.

The above are only specific implementations of this application, but the scope of protection of this application is not limited to this. Any person skilled in the art can easily conceive of changes or substitutions within the technical scope disclosed in this application, which shall cover Within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A sound generating device, characterized by comprising a first magnetically permeable structure, a first magnetic element, a second magnetic element, a voice coil group, and a second magnetically permeable structure, wherein:

The first magnetic element is connected with the first magnetically conductive structure to form a first vibrating body of the sound generating device;

The second magnetic element is arranged on a side of the second magnetically permeable structure close to the first magnetic element, and the voice coil assembly is sleeved on the second magnetic element and fixed to the second magnetic element. Elements to form the second vibrating body of the sound generating device; the first magnetic element and the second magnetic element repel, so that there is a set distance between the first vibrating body and the second vibrating body;

The voice coil group includes at least two voice coils connected in series, and part of the voice coils of the at least two voice coils connected in series are connected in parallel with a high-frequency short-circuit element. When the frequency of the AC signal of the group is the set value, the high-frequency short-circuit element causes the parallel-connected voice coils to be in a short-circuit state.
The sound generating device according to claim 1, wherein the high-frequency short-circuit element is a capacitive element, and the capacitance value of the capacitive element C=(1/(k*Re2)-1/Ze2)/(j* 2*pi*freq), k is the coefficient, Re is the DC impedance of the voice coil with capacitive elements in parallel, Ze is the AC impedance of the voice coil with the capacitive elements in parallel, freq is within the range of Ze>Re The frequency of the AC signal applied to the voice coil.
3. The sound emitting device of claim 1 or 2, wherein the first magnetically conductive structure has a first accommodating groove, and the first magnetic element is accommodated in the first accommodating groove.
The sound generating device according to any one of claims 1 to 3, wherein the second magnetically permeable structure has a second accommodating groove, and the voice coil group and the second magnetic element are accommodated in the The second accommodating slot.
The sound generating device according to any one of claims 1 to 4, wherein the projection of the second magnetic element on the first magnetically permeable structure falls on the first magnetic element on the first magnetic element. Within the projection on the magnetically permeable structure.
5. The sound generating device according to any one of claims 1 to 5, wherein the at least two voice coils connected in series are coaxially arranged and overlapped along the axial direction of the at least two voice coils.
The sound generating device according to any one of claims 1 to 5, wherein the at least two voice coils connected in series are arranged coaxially, and are sleeved along the radial direction of the at least two voice coils.
The sound generating device according to any one of claims 1 to 7, wherein the sound generating device has a first magnetic field space and a second magnetic field space, and the magnetic field strength of the first magnetic field space is greater than that of the second magnetic field space. The magnetic field strength;

The voice coil group includes a first voice coil and a second voice coil, the number of turns of the first voice coil is equal to the number of turns of the second voice coil, and the second voice coil is connected in parallel with a capacitive element; A voice coil is arranged in the first magnetic field space, and the second voice coil is arranged in the second magnetic field space.
The sound generating device according to any one of claims 1 to 7, wherein the sound generating device has a first magnetic field space and a second magnetic field space, and the magnetic field strength of the first magnetic field space is greater than that of the second magnetic field space. The magnetic field strength;

The voice coil set includes a first voice coil and a second voice coil, the number of turns of the first voice coil is greater than the number of turns of the second voice coil, and the first voice coil is disposed in the first magnetic field space Inside, the second voice coil is arranged in the second magnetic field space.
9. The sound emitting device of claim 9, wherein the second voice coil is connected in parallel with a capacitive element, and the capacitance of the capacitive element is C=(1/(k*Re2)-1/Ze2)/( j*2*pi*freq), k is the coefficient, Re is the DC impedance of the voice coil with capacitive elements in parallel, Ze is the AC impedance of the voice coil with the capacitive elements in parallel, freq is the interval of Ze>Re The frequency of the AC signal applied to the voice coil within the range.
A terminal device, characterized by comprising a display screen, a middle frame, a rear case, and the sounding device according to any one of claims 1 to 10, wherein:

The display screen and the rear case are separately arranged on both sides of the middle frame, the sound generating device is arranged between the display screen and the middle frame, and the middle frame is used to carry the display screen and the middle frame. The sounding device;

The first vibrating body of the sound generating device is fixed to the display screen, and the second vibrating body is fixed to the middle frame.