WO2021058011A1 - Conductive film for sound production device and sound production device - Google Patents

Abstract

Disclosed are a conductive film for a sound production device and a sound production device. The conductive film comprises a conductive layer and substrate layers located on two sides of the conductive layer, and the conductive film comprises an inner side portion, a deformation portion, and an outer side portion; the conductive layer comprises a first conductive layer disposed on the inner side portion, a second conductive layer disposed on the deformation portion, and a third conductive layer disposed on the outer side portion, and two ends of the second conductive layer are electrically connected to the first conductive layer and the third conductive layer respectively; the first conductive layer and the third conductive layer are both made of metal foil, the second conductive layer is a conductive adhesive layer formed by means of coating or printing, and the Young's modulus of the second conductive layer is smaller than the Young's modulus of the metal foil. One technical effect of the present invention is that the conductive film has conductivity and can be used not only as a sound production diaphragm, but also as a supporting diaphragm.

Description

Conductive film for sounding device and sounding device Technical field

The present invention relates to the field of electro-acoustic conversion technology, and more specifically, the present invention relates to a conductive film for a sound emitting device and a sound emitting device.

Background technique

The sounding device generally includes a diaphragm and a voice coil combined on one side of the diaphragm, and also includes an electrical connection that electrically connects the internal circuit and the external circuit of the sounding device. Among them, the voice coil includes two voice coil leads. The two voice coil leads are electrically connected to the two pads of the electrical connector by spot welding. The electrical connector is electrically connected to the external circuit at the same time to pass the electrical signal of the terminal product. Control the electrical signal in the voice coil.

Generally speaking, the lead wire of the voice coil needs to run a certain length of thread, and then it is suspended in the air to realize the electrical connection with the electrical connector. Although the floating lead structure can achieve higher sensitivity, due to the limitation of the lead floating, the amplitude cannot be too large, and the risk of disconnection is high, the low frequency effect is not significant enough, and it cannot provide a better user hearing experience.

In recent years, many researchers have begun to develop diaphragms with conductive functions, which makes conductive diaphragms more widely used in sound generating devices. For conductive films, the current main methods are electrophoresis conductors, electroplated conductors, injection molded conductors in the diaphragm, adding conductive coatings, adding conductive ink layers, and laser etching. However, these methods mentioned above all have the disadvantages of difficulty in technical implementation, low mass production, high cost, low reliability and low acoustic performance.

Summary of the invention

An object of the present invention is to provide a conductive film for a sound emitting device and a new technical solution for the sound emitting device.

According to a first aspect of the present invention, there is provided a conductive film for a sound emitting device, which includes a conductive layer and a substrate layer located on both sides of the conductive layer, the conductive film includes an inner side portion located on the inner side, and is provided in the conductive layer. A bent deformed part outside the inner part, and an outer part arranged outside the deformed part;

The conductive layer includes a first conductive layer provided on the inner portion, a second conductive layer provided on the deformed portion, and a third conductive layer provided on the outer portion, the second conductive layer Two ends of the layer are respectively electrically connected to the first conductive layer and the third conductive layer, and the first conductive layer, the second conductive layer and the third conductive layer are connected to form at least one conductive circuit;

The first conductive layer and the third conductive layer are both made of metal foil, the second conductive layer is a conductive adhesive layer formed by coating or printing, and the Young's modulus of the second conductive layer is less than The Young's modulus of the metal foil.

Preferably, both ends of the second conductive layer extend to the first conductive layer and the third conductive layer, respectively.

Preferably, the conductive adhesive layer includes conductive particles, a binder, and a solvent, and the conductive particles are at least one of gold, silver, copper, aluminum, zinc, nickel powder or alloy powder.

Preferably, the adhesive is one of epoxy type, acrylic type, polyurethane type and silicone type adhesive.

Preferably, the solvent is one of butyl anhydride acetate, diethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate and isophorone.

Preferably, the thickness of the conductive adhesive layer is 6 μm-15 μm, and the square resistance of the conductive adhesive layer is 10-30 mΩ/mm ² /mil.

Preferably, the hardness of the conductive adhesive layer is less than or equal to 3H.

Preferably, the first conductive layer and the third conductive layer are both copper foils.

Preferably, the substrate layer includes a first substrate layer and a second substrate layer directly attached to the conductive layer, and the first conductive layer and the third conductive layer are formed by hot pressing or bonding. Connected with the first substrate layer in a manner;

After the conductive lines are formed by etching on the first conductive layer and the third conductive layer, the second conductive layer is coated or printed with the first substrate layer and the first conductive layer. Layer and the third conductive layer are connected together;

The second substrate layer and the first substrate layer, the first conductive layer, the second conductive layer, and the third conductive layer are connected together by hot pressing or bonding.

Preferably, the substrate layer includes a first substrate layer and a second substrate layer directly attached to the conductive layer, and the first substrate layer is a thermoplastic elastomer layer;

The first conductive layer and the third conductive layer are connected to the first substrate layer by hot pressing;

After the conductive lines are formed by etching on the first conductive layer and the third conductive layer, the second conductive layer is coated or printed with the first substrate layer and the first conductive layer. The layer and the third conductive layer are connected together.

Preferably, the second substrate layer is a thermoplastic elastomer layer, the second substrate layer and the first substrate layer, the first conductive layer, the second conductive layer, and the third The conductive layers are connected together by hot pressing.

Preferably, the thermoplastic elastomer is TPU material or TPEE material.

Preferably, the substrate layer further includes a third substrate layer, and the third substrate layer is attached to the first substrate layer and/or the second substrate layer away from the conductive layer. On the surface.

Preferably, the material of the third substrate layer is plastic, thermoplastic elastomer or rubber.

Preferably, the material of the third substrate layer is any one of PEEK, PAR, PEI, PI, PPS, PEN, PET, TPEE, and TPU.

Preferably, a glue layer is provided between the third substrate layer and the first substrate layer and/or the third substrate layer.

Preferably, an inner pad is provided on the first conductive layer, an outer pad is provided on the third conductive layer, and the inner pad is configured to be connected to a voice coil, and the outer pad Configured as: used to connect with external circuits;

Both the inner pad and the outer pad are exposed from the substrate layer.

Preferably, the first conductive layer, the second conductive layer, and the third conductive layer each include at least two parts that are independent of each other. The first conductive layer, the second conductive layer, and the third conductive layer At least two independent conductive lines are formed.

According to a second aspect of the present invention, there is provided a sound generating device, including a vibration system and a magnetic circuit system matched with the vibration system;

The vibration system includes a sounding diaphragm and a voice coil combined on one side of the sounding diaphragm, and the sounding diaphragm adopts the conductive film described above.

According to a third aspect of the present invention, there is provided a sound generating device including a vibration system and a magnetic circuit system matched with the vibration system;

The vibration system includes a sounding diaphragm, a voice coil coupled to one side of the sounding diaphragm, and a supporting diaphragm for elastically supporting the voice coil, and the supporting diaphragm adopts the conductive film as described above.

In the conductive film provided by the embodiment of the present invention, the conductive layer is composited inside the substrate layer, the first conductive layer and the third conductive layer on the inner and outer sides are made of metal foil, and the second conductive layer is located on the deformed portion Using a material with a Young’s modulus smaller than the above-mentioned metal foil, the above-mentioned structure is arranged, the conductive film is connected with the voice coil, and the voice coil lead can be extended for a short length to be connected to the first conductive layer, and then the third conductive layer is electrically connected The layer is connected with the external circuit, and the voice coil lead does not need to be provided with a suspended structure, so the risk of disconnection can be avoided. The vibration system of the sound device can have large amplitude and high sensitivity, which improves low-frequency performance.

In addition, the conductive film of the present invention overcomes the problems of difficulty and low reliability of the conductive film in the prior art, and can realize mass production. Specifically, the first conductive layer and the third conductive layer use metal foils with a high Young's modulus, which can improve the structural strength of the inner and outer parts, and make the two parts less likely to be deformed. The carrier for the voice coil lead welding, the third conductive layer is used as the carrier for welding with the external circuit. The use of metal foil can withstand high temperature during welding without scalding the base layer of the conductive film; and the second conductive layer adopts Young's modulus Smaller materials, such as conductive adhesive, make the second conductive layer adapt to repeated bending and deformation without breaking, and prevent the conductive layer from being broken due to frequent deformation of the deformed part during the reciprocating vibration of the conductive film.

Through the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, other features and advantages of the present invention will become clear.

Description of the drawings

The drawings incorporated in the specification and constituting a part of the specification illustrate the embodiments of the present invention, and together with the description are used to explain the principle of the present invention.

Fig. 1 is a schematic structural diagram of a sound emitting device in an embodiment of the present invention.

Fig. 2 is a schematic diagram of the structure of a conductive film in an embodiment of the present invention.

3 is a schematic plan view of the first conductive layer and the third conductive layer in the conductive film in an embodiment of the present invention.

Fig. 4 is a schematic plan view of a second conductive layer in a conductive film in an embodiment of the present invention.

Fig. 5 is a schematic plan view of a conductive layer in a conductive film in an embodiment of the present invention.

Fig. 6 is a cross-sectional view of part A in Fig. 5.

Fig. 7 is a cross-sectional view of part B in Fig. 5.

Fig. 8 is a schematic structural diagram of a sound generating device in another embodiment of the present invention.

Fig. 9 is an exploded schematic diagram of the sound generating device in the embodiment of Fig. 8.

FIG. 10 is a schematic diagram of the structure of the conductive film in the embodiment of FIG. 8.

In the figure: 10, housing; 20, vibration system; 201, sounding diaphragm; 202, voice coil; 203, supporting diaphragm; 30, magnetic circuit system; 1, inner side; 11, first conductive layer; 111, first 1. Partition part; 2. Deformation part; 21. Second conductive layer; 211. Electrical connection arm; 3. Outer part; 31. Third conductive layer; 311. Second partition; 4. First substrate layer; 5. , The second base material layer; 6, the third base material layer; 7, the inner pad; 8, the outer pad; 9, the reinforcement part.

detailed description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless specifically stated otherwise, the relative arrangement of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention.

The following description of at least one exemplary embodiment is actually only illustrative, and in no way serves as any limitation to the present invention and its application or use.

The technologies, methods, and equipment known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be regarded as part of the specification.

In all examples shown and discussed herein, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiment may have different values.

It should be noted that similar reference numerals and letters indicate similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in the subsequent drawings.

With reference to Figures 1 to 7, the sound-producing device used in electronic devices capable of sounding such as earphones and mobile phones generally includes a housing 10, a vibration system 20 and a magnetic circuit system 30 mounted on the housing 10, where all The vibration system 20 includes a sounding diaphragm 201 and a voice coil 202 combined with the sounding diaphragm 201. The magnetic circuit system 30 includes a magnetic yoke and a central magnetic circuit part provided on the bottom wall of the magnetic yoke. And the side magnetic circuit part, a magnetic gap is formed between the central magnetic circuit part and the side magnetic circuit part, and the voice coil 202 extends into the magnetic gap. After the current is applied to the voice coil 202, the voice coil 202 Under the action of the magnetic field of the magnetic circuit system 30, it is forced to vibrate, which in turn drives the sound diaphragm 201 to vibrate and produce sound.

In some cases, in order to avoid polarization of the vibration system 20, an elastic support structure is further provided in the vibration system 20, such as a supporting diaphragm 203. The supporting diaphragm 203 can be combined with either end or outer side of the voice coil 202 and the housing 10. Meanwhile, under the action of supporting the diaphragm 203, the vibration system 20 can have a larger amplitude, which improves the low frequency performance of the product.

The embodiment of the present invention provides a conductive film used for the above-mentioned sound emitting device. The conductive film can be used for the sound emitting diaphragm 201 and can also be used for supporting the diaphragm 203.

As shown in FIG. 2 to FIG. 7, the conductive film includes a conductive layer and a substrate layer located on both sides of the conductive layer. The substrate layers on both sides wrap the conductive layer to prevent the conductive layer from contacting other parts and causing short circuits. phenomenon.

Further, the conductive film includes an inner portion 1 located on the inner side, a bent deformed portion 2 provided on the outer side of the inner portion 1, and an outer portion 3 provided on the outer side of the deformed portion 2. Among them, the voice coil 202 is connected to the inner part 1, and the outer part 3 is generally connected to a fixed part such as the housing 10.

The conductive layer includes a first conductive layer 11 provided on the inner portion 1, a second conductive layer 21 provided on the deformed portion 2, and a third conductive layer 31 provided on the outer portion 3 , Both ends of the second conductive layer 21 are electrically connected to the first conductive layer 11 and the third conductive layer 31, the first conductive layer 11, the second conductive layer 21 and the third conductive layer 31 The connection forms at least one conductive line.

In particular, the conductive layer in the embodiment of the present invention is made of different materials, the first conductive layer 11 and the third conductive layer 31 are both made of metal foil, and the second conductive layer 21 has a Young’s mold. The amount is less than the Young's modulus of the metal foil.

Wherein, an inner pad 7 is provided on the first conductive layer 11, an outer pad 8 is provided on the third conductive layer 31, and the inner pad 7 is configured to be connected to the voice coil 202, The outer pad 8 is configured to connect with an external circuit; both the inner pad 7 and the outer pad 8 are exposed from the base material layer to facilitate electrical connection.

In the above arrangement, on the one hand, the conductive film is connected to the voice coil 202, and the lead wire of the voice coil 202 can extend a short length to connect to the first conductive layer 11, and then connect to the external circuit through the electrically connected third conductive layer 31, The lead wire of the voice coil 202 does not need to be provided with a suspended structure, so the risk of disconnection can be avoided. The vibration system 20 of the sound device can have a large amplitude and high sensitivity, which improves the low frequency performance.

In addition, the conductive film of the present invention overcomes the problems of difficulty and low reliability of the conductive film in the prior art, and can realize mass production. Specifically, the first conductive layer 11 and the third conductive layer 31 use metal foils with a high Young's modulus, which can improve the structural strength of the inner part 1 and the outer part 3, so that the two parts are not easily deformed, and the first The conductive layer 11 is used as a carrier for welding with the lead wires of the voice coil 202, and the third conductive layer 31 is used as a carrier for welding with an external circuit. The use of metal foil can withstand high temperatures during welding and will not scald the substrate layer of the conductive film; and the second The conductive layer 21 is made of a material with a small Young's modulus, such as conductive glue, so that the second conductive layer 21 can adapt to repeated bending and deformation without breaking, and avoid the frequent deformation of the deformed part 2 during the reciprocating vibration of the conductive film, which leads to conduction. Fracture of the layer.

The foregoing provides an embodiment for electrically connecting the conductive film and the voice coil 202, but those skilled in the art should understand that the conductive film in the present invention can also be used in other scenarios, as long as the conductive film itself is based on the structure and function of the conductive film. Further having the above-defined conductive layer structure should be within the scope of protection of this patent. For example, in another embodiment, when a metal layer is attached to the conductive film as a movable plate of the capacitor, the conductive film The conductive layer can be used to achieve electrical connection with the movable electrode plate.

Both the first conductive layer 11 and the third conductive layer 31 of the present invention use metal foils. The thickness of the metal foil can be controlled within 5-36μm. For example, the first conductive layer 11 and the third conductive layer 31 are both copper foils. Copper foil is a thin sheet-like structure with low surface oxidation characteristics and can be easily attached to the surface of a variety of substrates of different materials. In addition, the copper material has better conductivity, which enables the formed conductive film to have good conductivity. The first conductive layer 11 and the third conductive layer 31 can be formed into a predetermined circuit pattern by etching, corrosion, etc., which are well known to those skilled in the art.

In an example of the present invention, the first conductive layer 11 and the third conductive layer 31 are rolled copper foil, for example, RA copper foil or HA copper foil. The rolled copper foil has excellent tensile strength and high elongation, and has good ductility when combined with the base layer of the conductive film. In addition, it should be noted that the first conductive layer 11 and the third conductive layer 31 are not limited to be made of the same material, and can be made of metal foils of different materials according to specific needs.

Further, the two ends of the second conductive layer 21 respectively extend to the first conductive layer 11 and the third conductive layer 31, and the two ends of the second conductive layer 21 may partially or completely cover the first conductive layer 11 and the third conductive layer 31. The first conductive layer 11 and the third conductive layer 31 ensure the reliability of the connection between the two and realize a good conductive connection. During the vibration process of the conductive film, there will be no separation of the connection between the two.

Specifically, the second conductive layer 21 is a conductive layer formed by coating or printing. The second conductive layer 21 is a conductive adhesive layer or a conductive ink layer. The second conductive layer 21 formed by the conductive adhesive layer or the conductive ink layer has a small Young's modulus, has good flexibility and fatigue resistance, and is resistant to damage. The stronger the capacity, the second conductive layer 21 will not have the risk of fracture when the vibration system 20 vibrates in a large amplitude state.

As a specific embodiment, the second conductive layer 21 is a coated or printed conductive adhesive layer,

Conductive adhesives are mainly composed of conductive particles, adhesives, solvents, additives, etc. High-temperature conductive adhesives will also be doped with glass powder. Among them, the adhesive generally chooses epoxy, acrylic, polyurethane, and silicone adhesives. After curing, the adhesive forms the molecular skeleton structure of the conductive adhesive layer, which provides mechanical and adhesive performance guarantees, and Make conductive particles form channels. The solvent is butyl anhydride acetate, diethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, and isophorone. Due to the high amount of conductive particles added, the viscosity of the conductive adhesive is greatly increased, which often affects the process performance of the adhesive. In order to reduce the viscosity and achieve good manufacturability and rheology, it is also necessary to add a solvent or reactive diluent to the conductive adhesive.

The conductive particles may specifically be at least one of gold, silver, copper, aluminum, zinc, nickel powder or alloy powder. In this specific embodiment, the conductive adhesive layer is conductive silver adhesive, and the conductive particles in the conductive adhesive layer are silver particles. The price of silver is relatively cheap, the resistance is low, the conductivity is good, and it is not easy to oxidize.

In a specific embodiment, the particle size of the silver particles is less than or equal to 1 μm. When the filling ratio of the silver particles is constant and the conductive adhesive layer has the same thickness, there are more silver particles, and the gap between the silver particles is smaller, and the conductivity is obtained. Promote. Further, the particle size of the silver particles is less than or equal to 100 nm, the nano-scale silver particles can further improve the conductivity of the second conductive layer 21, and the printing methods of the conductive silver glue are diverse and flexible, and the nanoimprinting process can be used to improve the printing accuracy. It can be upgraded from the micron level of screen printing to the nano level.

Specifically, the thickness of the conductive adhesive layer is 6 μm-15 μm, which is compounded in the substrate layer with high reliability and low resistance. If the thickness of the conductive adhesive layer exceeds 15 μm, it is easy to crack and fall off after curing. If the thickness is less than 6 μm, the electrical resistance of the conductive adhesive layer will be relatively high, which will affect the conductivity.

Specifically, the conductive adhesive layer has a cured resistance of 10-30mΩ/mm ² /mil. If the square resistance is too small, it is difficult to make it. If the square resistance is too large, the thickness or width needs to be increased to compensate. The square resistance has been determined and the thickness has been determined. Next, the impedance of the finished product can be reduced by increasing the width, but in actual use, the width will not be increased indefinitely, so the smaller the square resistance, the better. The square resistance of the conductive adhesive layer is less than 30mΩ/mm ² /mil, which can ensure the second conductive layer 21 has a smaller impedance.

The hardness of the conductive adhesive layer after curing is less than or equal to 3H, the conductive film formed by the conductive adhesive layer and the substrate layer has good compliance, good resilience and toughness, and the sound device has better transient response and lower THD distortion . After the cured conductive adhesive layer has a hardness greater than 3H, the conductive adhesive layer will affect the compliance of the vibration system 20 and increase the THD distortion of the product.

In a specific embodiment, the above-mentioned first conductive layer 11, second conductive layer 21, and third conductive layer 31 each include at least two parts that are independent of each other. The first conductive layer 11 and the second conductive layer 21 And the third conductive layer 31 form at least two independent conductive lines.

In this specific embodiment, the first conductive layer 11 includes two parts that are independent of each other, and the third conductive layer 31 also includes two parts that are independent of each other. The second conductive layer 21 includes two parts located between the two sets of the first conductive layer 11 and the third conductive layer 31, and each part of the second conductive layer 21 may include two or more electrical connection arms 211. An inner pad 7 electrically connected to the first conductive layer 11 is provided on the first conductive layer 11, and an outer pad 8 electrically connected to the third conductive layer 31 is provided on the third conductive layer 31.

The inner pad 7 on the conductive film is electrically connected to the voice coil 202, and the outer pad 8 on the conductive film is electrically connected to an external circuit. Wherein, the outer pad 8 may be directly electrically connected to an external circuit, or may be electrically connected to an external circuit through an elastic piece provided on the housing 10 of the sound device. Those skilled in the art can flexibly adjust according to actual needs, and there is no limitation on this.

Further, the base material layer includes a first base material layer 4 and a second base material layer 5 directly attached to the conductive layer, and the first conductive layer 11 and the third conductive layer 31 are heated by hot pressing Or bonding with the first base material layer 4; when the first conductive layer 11 and the third conductive layer 31 are etched to form conductive lines, the second conductive layer 21 The first substrate layer 4, the first conductive layer 11, and the third conductive layer 31 are connected together by coating or printing; the second substrate layer 5 is connected to the first substrate The material layer 4 and the first conductive layer 11, the second conductive layer 21, and the third conductive layer 31 are connected together by hot pressing or bonding.

Wherein, the glue layer used in the above bonding method can be any one of hot melt glue, acrylic glue, and silica gel.

Among them, the materials of the first base material layer 4 and the second base material layer 5 may be the same or different, and may be selected from plastics, thermoplastic elastomers and silica gels in common materials for diaphragms, such as PEEK, PAR, PEI, PI, PPS, PEN, PET, etc., thermoplastic elastomers such as TPEE, TPU, etc.

The thickness of the first substrate layer 4 and the second substrate layer 5 can be flexibly adjusted by those skilled in the art as required. In an example of the present invention, the thickness of the first base material layer 4 and the second base material layer 5 can be controlled within 3-50 μm, respectively, and the first base material layer 4 and the second base material layer 5 Can play a good protective effect on the conductive layer located in the middle. By reasonably adjusting the thickness of the base material layer and the conductive layer on both sides, it can also ensure that the conductive film as a whole has appropriate rigidity and flexibility, which can make the conductive film more stable when vibrating.

As a specific embodiment, the substrate layer includes a first substrate layer 4 and a second substrate layer 5 directly attached to the conductive layer, and the first substrate layer 4 is a thermoplastic elastomer layer; The first conductive layer 11 and the third conductive layer 31 are connected to the first substrate layer 4 by hot pressing; when the first conductive layer 11 and the third conductive layer 31 After the conductive lines are formed by etching, the second conductive layer 21 is connected to the first substrate layer 4, the first conductive layer 11, and the third conductive layer 31 by coating or printing. .

As a preferred solution, the material of the first substrate layer 4 is a thermoplastic polyurethane elastomer TPU material or a thermoplastic polyester elastomer TPEE material. Among them, the thermoplastic polyurethane elastomer TPU or the thermoplastic polyester elastomer TPEE all belong to the thermoplastic elastomer TPE, and both have high adhesion at high temperatures. Therefore, when the first substrate layer 4 is made of thermoplastic polyurethane elastomer TPU or thermoplastic polyester elastomer TPEE, in the way of hot pressing, no adhesive is needed, and the first substrate layer 4 can be connected to the first conductive layer 11 It is well connected to the third conductive layer 31. It has the characteristics of simple combination, good firmness and not easy to separate.

It should be noted that when the metal foils of the first conductive layer 11 and the third conductive layer 31 and the first substrate layer 4 are connected together by hot pressing, the hot pressing temperature is relatively high, usually around 110°C. At this time, the first substrate layer 4 is based on the thermoplastic elastomer TPE based on the material used, which can form a viscous fluid state, at this time, the bonding force is strong, and it can be firmly connected with the two conductive layers. After the conductive lines are etched on the two conductive layers, the two conductive layers and the first substrate layer 4 need to be subjected to a rolling process. The rolling treatment is usually carried out at room temperature. At room temperature, the thermoplastic elastomer TPE has no adhesive force and will not cause impurities such as dust to adhere to the first substrate layer 4 and the two conductive layers, thereby avoiding the influence on the subsequent molding process.

Still further, the second base material layer 5 is also a thermoplastic elastomer layer, the second base material layer 5 and the first base material layer 4, the first conductive layer 11, the second conductive layer The layer 21 and the third conductive layer 31 are connected together by hot pressing.

The second base material layer 5 also uses a thermoplastic elastomer, and is compounded by hot pressing. There is no need to use an adhesive between the second base material layer 5 and the first base material layer 4. The first base material layer 4 and the second base material layer 5 have no adhesive force at room temperature, and the second base material layer 5 and Before the first base material layer 4 is hot pressed, if the alignment between the second base material layer 5 and the first base material layer 4 is not accurate, the position can be corrected again without adhesion, and the alignment of the two can be ensured Accuracy: The inner pads 7 and outer pads 8 on the first conductive layer 11 and the second conductive layer 21 can be accurately exposed from the reserved hollow positions of the base material layer, ensuring the reliability of the electrical connection.

It should be noted that, in the conductive film provided by the embodiment of the present invention, the materials of the first substrate layer 4 and the second substrate layer 5 can be the same or different, and those skilled in the art can flexibly adjust according to actual needs. For example, the first substrate layer 4 uses thermoplastic polyurethane elastomer TPU, and the second substrate layer 5 uses thermoplastic polyester elastomer TPEE. For another example, both the first substrate layer 4 and the second substrate layer 5 are made of thermoplastic polyurethane elastomer TPU, and the two substrate layers are attached to the two surfaces of the conductive layer. For another example, the two substrate layers are made of thermoplastic polyester elastomer TPEE, and the two substrate layers are attached to the two surfaces of the conductive layer.

In addition, the base material layer may also include a third base material layer 6, and the third base material layer 6 is attached to the first base material layer 4 and/or the second base material layer 5 far away from each other. The surface of the conductive layer. The third substrate layer 6 may be compounded only on the first substrate layer 4, or the third substrate layer 6 may be compounded only on the second substrate layer 5, or, on the first substrate layer 4 and the second substrate layer 6 The third substrate layer 6 is compounded on the material layer 5, and those skilled in the art can flexibly choose according to actual needs, and there is no restriction on this.

The material of the third substrate layer 6 is plastic, thermoplastic elastomer or rubber. Specifically, the material of the third substrate layer 6 is any one of PEEK, PAR, PEI, PI, PPS, PEN, PET, TPEE, and TPU.

In the case where the first base material layer 4 and the second base material layer 5 are thermoplastic elastomers, the third base material layer 6 can be combined with the first base material layer 4 or the second base material layer 5 by hot pressing. The first base material layer 4 and the second base material layer 5 are made of thermoplastic elastomers, which have good adhesion at high temperatures and can be firmly combined with the surface of the third base material layer 6, and No additional special adhesive is needed, the bonding method is relatively simple, and the bonding fastness is better. As a preferred embodiment, the third base material layer 6 can be connected to the first base material layer 4 by thermal compression first, and then a conductive layer is formed on the first base material layer 4. The third substrate layer 6 can be connected to the second substrate layer 5 by thermal compression first, and then connected to the first substrate layer 4 and the conductive layer by thermal compression. However, the present invention is not limited to the above-mentioned forming steps.

As a different embodiment, a glue layer is provided between the third substrate layer 6 and the first substrate layer 4 and/or the third substrate layer 6. Specifically, the third substrate layer 6 may be connected to the first substrate layer 4 through an adhesive layer first, and then a conductive layer is formed on the first substrate layer 4. The third substrate layer 6 can be connected to the second substrate layer 5 through an adhesive layer first, and then connected to the first substrate layer 4 and the conductive layer by thermal compression. However, the present invention is not limited to the above-mentioned forming steps.

As shown in FIG. 1 to FIG. 7, an embodiment of the present invention provides a sound generating device. As described above, the sound device includes a vibration system 20 and a magnetic circuit system 30 that cooperates with the vibration system 20. The sound generating device further includes a housing 10 having a receiving cavity, and both the vibration system 20 and the magnetic circuit system 30 are accommodated in the receiving cavity. Wherein, the vibration system 20 includes a sounding diaphragm 201 and a voice coil 202 combined on one side of the sounding diaphragm 201. The sounding diaphragm 201 adopts the conductive film in the above-mentioned embodiment. During the working process of the sounding device, the voice coil 202 with electrical signals interacts with the magnetic circuit system 30 to generate up and down vibrations, which can drive the sounding diaphragm 201 to produce sound.

The sound emitting device may have a circular structure or a rectangular structure. This embodiment illustrates a sound emitting device with a circular structure, and the corresponding sound emitting diaphragm 201 is circular.

As a specific embodiment, the first conductive layer 11 and the second conductive layer 21 are made of copper foil, the first conductive layer 11 has a ring structure, and the first conductive layer 11 is located on the edge of the inner side 1 of the conductive film Close to the deformed portion 2, the first conductive layer 11 can be used to form an electrical connection with the voice coil 202. Specifically, the voice coil 202 usually has two leads of the voice coil 202, for the first conductive layer 11, in order to form two independent conductive lines electrically connected to the two leads of the voice coil 202. In this embodiment, it is designed to provide a first partition 111 at two opposite positions of the ring-shaped first conductive layer 11, and no conductive layer is provided at the position where the first partition 111 is located, so that the first conductive layer 11 Is divided into two independent parts. In addition, an inner pad 7 electrically connected to the first conductive layer 11 is provided inside the first conductive layer 11. Wherein, the number of the inner pads 7 is set to at least two, which can be used for electrical connection with the two leads of the voice coil 202.

Wherein, an inner pad 7 is provided corresponding to each conductive circuit, and the lead of the voice coil 202 can be electrically connected to any one of the two inner pads 7 of the corresponding conductive circuit. Of course, the number of inner pads 7 can also be set to more, for example, four, six, etc., and those skilled in the art can flexibly adjust according to actual needs, and there is no limitation on this.

Further, the third conductive layer 31 has a ring structure. The third conductive layer 31 is located at the edge position of the conductive film, that is, the position of the outer portion 3, and is used for connecting with an external circuit. Similarly, in order to form two independent conductive lines, in this embodiment, it is designed to provide a second partition 311 at two opposite positions of the ring-shaped second conductive layer 21. The second partition 311 is not located at the position where the second partition 311 is located. The conductive layer is provided so that the third conductive layer 31 can be composed of two independent parts.

In addition, outer pads 8 are respectively provided on the third conductive layer 31. The outer pad 8 is used to electrically connect with the electrical connector on the housing 10 of the sounding device by welding or the like. Wherein, the first base material layer 4 and the second base material layer 5 corresponding to the upper and lower parts of the outer pad 8 are both provided with avoiding areas for avoiding the outer pad 8 so that the outer pad 8 It can be properly exposed from the substrate layer to facilitate electrical connection with external circuits.

In addition, a metal protective layer can also be provided on the surfaces of the inner pad 7 and the outer pad 8. The metal protection layer can be formed by electroplating, for example, and of course, a metal protection layer can also be attached to it, which is not limited.

The second conductive layer 21 in this embodiment is a bent strip structure printed with conductive glue. The second conductive layer 21 in this embodiment includes two parts, each of which includes two strip-shaped electrical connection arms. 211. The four electrical connection arms 211 are arranged symmetrically at the center, which can ensure the symmetry of the vibration of the sounding diaphragm 201 and is not easy to produce polarization.

In addition, when the conductive film of the present invention is used as the sound-emitting diaphragm 201, it may also include a rigid reinforcement part 9, and the reinforcement part 9 is bonded to the inner side 1 of the conductive film. When a rigid reinforcing part 9 is provided on the conductive film of the present invention, the reinforcing part 9 and the conductive film can be joined together in a manner known to those skilled in the art (for example, bonding). The high frequency characteristics of the conductive film can be effectively improved by adding the rigid reinforcement 9 on the conductive film. However, it should be noted that for the conductive film of the present invention, a person skilled in the art can choose to provide or not provide the reinforcing part 9 on it according to actual needs, and there is no limitation on this.

As shown in FIGS. 8 to 10, an embodiment of the present invention also provides a sound generating device, which includes a vibration system 20 and a magnetic circuit system 30 that cooperates with the vibration system 20. The vibration system 20 includes a sounding diaphragm 201, a voice coil 202 coupled to one side of the sounding diaphragm 201, and a supporting diaphragm 203 for elastically supporting the voice coil 202. Wherein, the supporting diaphragm 203 adopts the conductive film in the above-mentioned embodiment of the present invention.

The sound emitting device may be a circular structure or a rectangular structure. The illustration in this embodiment provides a rectangular structure of the sound emitting device, and the corresponding sounding diaphragm 201 and the voice coil 202 are both rectangular.

As a specific embodiment, the voice coil 202 includes two opposite long sides and two opposite short sides, and a supporting diaphragm 203 is provided on each short side of the voice coil 202. For example, at least one of the supporting diaphragms 203 is a conductive film of the present invention. When the conductive film of the present invention is used as the supporting diaphragm 203, it has the advantage of stable vibration, can be used to prevent the internal vibration system 20 from being polarized, can increase the loudness of the sound device and reduce nonlinear distortion.

When the conductive film of the present invention is used to support the diaphragm 203, an outer portion 3, an inner portion 1 and a deformed portion 2 are distributed on the supporting diaphragm 203. Wherein, the outer part 3 is configured to be connected to the housing 10, and the inner part 1 is configured to be connected to the voice coil 202. The conductive layer includes a first conductive layer 11 distributed on the inner portion 1, a second conductive layer 21 distributed on the deformed portion 2, and a third conductive layer 31 distributed on the outer portion 3 . In addition, the second conductive layer 21 is connected to the first conductive layer 11 and the third conductive layer 31, and the first conductive layer 11, the second conductive layer 21 and the third conductive layer 31 are connected to form two independent conductive layers. The first conductive layer 11 is provided with two inner pads 7 electrically connected to the two conductive lines, and the third conductive layer 31 is provided with two outer solders corresponding to the two conductive lines. Disk 8. Wherein, the inner pad 7 can be used for electrical connection with the voice coil 202, and the outer pad 8 can be used for electrical connection with an external circuit, so that the lead of the voice coil 202 does not need to run out a long thread. The realization of the electrical connection between the voice coil 202 and the conductive film can effectively avoid the disconnection of the lead wire of the voice coil 202 during operation, and improve the stability of the product.

On the other hand, an embodiment of the present invention also provides an electronic device, which includes the above-mentioned sound emitting device. Wherein, the electronic device may be, but is not limited to, a mobile phone, a tablet computer, a smart wearable device, a smart watch, a walkie-talkie, a TV, a smart speaker, etc. The electronic device may include a casing and the sound emitting device of the embodiment of the present disclosure, and the sound emitting device is housed and fixed in the casing.

Although some specific embodiments of the present invention have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present invention. The scope of the invention is defined by the appended claims.

Claims (20)

1. A conductive film for a sounding device, comprising a conductive layer and a substrate layer located on both sides of the conductive layer, characterized in that:

   The conductive film includes an inner portion located on the inner side, a bent deformed portion provided on the outer side of the inner portion, and an outer portion provided on the outer side of the deformed portion;

   The conductive layer includes a first conductive layer provided on the inner portion, a second conductive layer provided on the deformed portion, and a third conductive layer provided on the outer portion, the second conductive layer Two ends of the layer are respectively electrically connected to the first conductive layer and the third conductive layer, and the first conductive layer, the second conductive layer and the third conductive layer are connected to form at least one conductive circuit;

   The first conductive layer and the third conductive layer are both made of metal foil, the second conductive layer is a conductive adhesive layer formed by coating or printing, and the Young's modulus of the second conductive layer is less than The Young's modulus of the metal foil.
2. The conductive film for a sound emitting device according to claim 1, wherein both ends of the second conductive layer extend to the first conductive layer and the third conductive layer, respectively.
3. The conductive film for a sounding device according to claim 1, wherein the conductive adhesive layer comprises conductive particles, a binder, and a solvent, and the conductive particles are gold, silver, copper, aluminum, zinc, and nickel. At least one of the powder or alloy powder.
4. The conductive film for a sound generating device according to claim 3, wherein the adhesive is one of epoxy type, acrylic type, polyurethane type and silicone type adhesive.
5. The conductive film for a sound device according to claim 3, wherein the solvent is butyl anhydride acetate, diethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, and isophorone. Kind of.
6. The conductive film for a sound emitting device according to claim 3, wherein the thickness of the conductive adhesive layer is 6 μm-15 μm, and the square resistance of the conductive adhesive layer is 10-30 mΩ/mm ² /mil.
7. The conductive film for a sound emitting device according to claim 1, wherein the hardness of the conductive adhesive layer is less than or equal to 3H.
8. The conductive film for a sound emitting device according to claim 1, wherein the first conductive layer and the third conductive layer are both copper foils.
9. The conductive film for a sound emitting device according to claim 1, wherein the substrate layer comprises a first substrate layer and a second substrate layer directly bonded to the conductive layer, and the first The conductive layer and the third conductive layer are connected to the first substrate layer by hot pressing or bonding;

   After the conductive lines are formed by etching on the first conductive layer and the third conductive layer, the second conductive layer is coated or printed with the first substrate layer and the first conductive layer. Layer and the third conductive layer are connected together;

   The second substrate layer and the first substrate layer, the first conductive layer, the second conductive layer, and the third conductive layer are connected together by hot pressing or bonding.
10. The conductive film for a sound emitting device according to claim 1, wherein the substrate layer comprises a first substrate layer and a second substrate layer directly bonded to the conductive layer, and the first The substrate layer is a thermoplastic elastomer layer;

    The first conductive layer and the third conductive layer are connected to the first substrate layer by hot pressing;

    After the conductive lines are formed by etching on the first conductive layer and the third conductive layer, the second conductive layer is coated or printed with the first substrate layer and the first conductive layer. The layer and the third conductive layer are connected together.
11. The conductive film for a sound generating device according to claim 10, wherein the second base material layer is a thermoplastic elastomer layer, the second base material layer and the first base material layer, and the The first conductive layer, the second conductive layer, and the third conductive layer are connected together by hot pressing.
12. The conductive film for a sounding device according to claim 11, wherein the thermoplastic elastomer is a TPU material or a TPEE material.
13. The conductive film for a sound emitting device according to any one of claims 9-12, wherein the substrate layer further comprises a third substrate layer, and the third substrate layer is attached to the first substrate layer. The substrate layer and/or the surface of the second substrate layer away from the conductive layer.
14. The conductive film for a sound emitting device according to claim 13, wherein the material of the third substrate layer is plastic, thermoplastic elastomer or rubber.
15. The conductive film for a sound emitting device according to claim 14, wherein the material of the third substrate layer is any one of PEEK, PAR, PEI, PI, PPS, PEN, PET, TPEE, TPU Kind.
16. The conductive film for a sounding device according to claim 13, wherein a glue layer is provided between the third substrate layer and the first substrate layer and/or the third substrate layer .
17. The conductive film for a sounding device according to claim 1, wherein the first conductive layer is provided with an inner pad, the third conductive layer is provided with an outer pad, and the inner pad is Is configured to be used for connection with a voice coil, and the outer pad is configured to be used for connection with an external circuit;

    Both the inner pad and the outer pad are exposed from the substrate layer.
18. The conductive film for a sound emitting device according to claim 1, wherein the first conductive layer, the second conductive layer, and the third conductive layer each comprise at least two parts that are independent of each other, and the first conductive layer The conductive layer, the second conductive layer and the third conductive layer form at least two independent conductive lines.
19. A sound generating device, characterized by comprising a vibration system and a magnetic circuit system matched with the vibration system;

    The vibration system includes a sounding diaphragm and a voice coil combined on one side of the sounding diaphragm, and the sounding diaphragm adopts the conductive film according to any one of claims 1-18.
20. A sound generating device, characterized by comprising a vibration system and a magnetic circuit system matched with the vibration system;

    The vibration system includes a sounding diaphragm, a voice coil combined on one side of the sounding diaphragm, and a supporting diaphragm for elastically supporting the voice coil, and the supporting diaphragm adopts any one of claims 1-18 The conductive film.

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