Force-sensitive electrode, flexible pressure sensor and manufacturing method of flexible pressure sensor

Abstract

The invention discloses a force sensing electrode, a flexible pressure sensor and a manufacturing method of the flexible pressure sensor. The manufacturing method of the force-sensitive electrode comprises the following steps: providing an electric conductor and a glue melt, wherein the electric conductor is linear; the adhesive melt is laid on the electric conductor, so that the adhesive melt forms a conducting layer, and the resistance value of the conducting layer changes along with the change of the external force; and cooling the conductor and the conductive layer to obtain the force-sensitive electrode. The force-sensitive electrode prepared by the manufacturing method of the force-sensitive electrode can be used for a force-sensitive sensing structure, and has the advantages of high flexibility, stable and reliable electric connection, good measurement consistency, high sensitivity, good reliability and the like. Correspondingly, the flexible pressure sensor comprises the force-sensitive electrode, the manufacturing method of the flexible pressure sensor has the advantages of few process links, high production yield and the like, and the flexible pressure sensor manufactured by the manufacturing method of the flexible pressure sensor is good in flexibility, high in measurement accuracy, material-saving, high in reliability and high in reliability. And the method is suitable for various flexible, dynamic and complex curved surfaces.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pressure sensors, in particular to a force-sensitive electrode, a flexible pressure sensor and a manufacturing method thereof. BACKGROUND

[0002] With the rapid development of robot technology, intelligent cockpit technology and wearable technology, related products have brought a large number of new pressure sensing interaction needs, and the research and development focus of pressure sensing technology has gradually shifted from rigid interface measurement and static interface to complex curved surfaces and dynamic soft interfaces. However, mainstream pressure sensors often use metal strain gauges and silicon-based MEMS as the core of rigid force-sensitive sensing structures, which are difficult to conform to soft surfaces or complex curved surfaces, resulting in poor contact and missed detection, and are difficult to measure the pressure of the flexible interface of the skin and soft tissue, as well as the complex curved surface interface in electronic devices such as flexible robots and car seats. How to develop a force-sensitive electrode, a force-sensitive sensing structure and a flexible pressure sensor to better measure the pressure of complex curved surfaces and dynamic soft interfaces has become a technical problem to be solved. SUMMARY

[0003] The present application discloses a force-sensitive electrode, a flexible pressure sensor and a manufacturing method thereof. The prepared force-sensitive electrode can be used in a force-sensitive sensing structure. The force-sensitive electrode has the advantages of high flexibility, stable and reliable electrical connection, good measurement consistency, high sensitivity and good reliability. The flexible pressure sensor includes the force-sensitive electrode or the force-sensitive sensing structure. The manufacturing method of the flexible pressure sensor has the advantages of fewer process steps and high production yield. The flexible pressure sensor manufactured by the manufacturing method of the flexible pressure sensor has the advantages of good flexibility, high measurement accuracy, material saving and high reliability, and is suitable for various flexible, dynamic and complex curved surfaces.

[0004] In a first aspect, the present application provides a manufacturing method of a force-sensitive electrode, comprising: providing a conductive body and a glue melt, the conductive body being in a linear shape; applying the glue melt on the conductive body to form a conductive layer, wherein the resistance of the conductive layer changes with the change of external force; cooling the conductive body and the conductive layer to obtain the force-sensitive electrode.

[0005] In a second aspect, the present application provides a force-sensitive electrode, and the manufacturing method of the force-sensitive electrode comprises the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application.

[0006] In a third aspect, the present application provides a manufacturing method of a flexible pressure sensor, the manufacturing method of the flexible pressure sensor using the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application, or the manufacturing method of the flexible pressure sensor comprising the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application; or, The manufacturing method of the flexible pressure sensor comprises: providing a first substrate layer, a second substrate layer, a plurality of force-sensitive electrodes, and a plurality of conductive electrodes, wherein the first substrate layer and the second substrate layer are flexible, the force-sensitive electrode comprises a conductive body and a conductive layer, the conductive layer is applied to the conductive body, and the resistance of the conductive layer changes with the change of an external force; arranging the plurality of force-sensitive electrodes in the first substrate layer in a first direction at intervals; arranging the plurality of conductive electrodes in the second substrate layer in a second direction at intervals, the second direction being arranged at an angle to the first direction; correspondingly arranging the first substrate layer and the second substrate layer to electrically connect a part of the plurality of force-sensitive electrodes with a part of the plurality of conductive electrodes, thereby obtaining the flexible pressure sensor.

[0007] In a fourth aspect, the present application provides a flexible pressure sensor, the manufacturing method of the flexible pressure sensor comprising the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application, or the flexible pressure sensor comprising the force-sensitive electrode according to any one of the embodiments of the present application, or the manufacturing method of the flexible pressure sensor comprising the manufacturing method of the flexible pressure sensor according to any one of the embodiments of the present application; or, The flexible pressure sensor comprises a first substrate layer and a second substrate layer arranged oppositely, the first substrate layer having a plurality of force-sensitive electrodes arranged at intervals in a first direction thereon, the second substrate layer having a plurality of conductive electrodes arranged at intervals in a second direction thereon, the first direction being arranged at an angle to the second direction, a part of the plurality of force-sensitive electrodes overlapping and electrically connecting with a part of the plurality of conductive electrodes, wherein the force-sensitive electrode comprises a conductive body and a conductive layer, the conductive layer being applied to the conductive body, and the resistance of the conductive layer changing with the change of an external force.

[0008] In a fifth aspect, the present application provides an electronic device, the electronic device comprising the force-sensitive electrode according to any one of the embodiments of the present application; or the electronic device comprising the flexible pressure sensor according to any one of the embodiments of the present application; or the manufacturing method of the electronic device comprising the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application; or the manufacturing method of the electronic device comprising the manufacturing method of the flexible pressure sensor according to any one of the embodiments of the present application.

[0009] The force-sensitive electrode, the flexible pressure sensor and the manufacturing method thereof can make the molecules of the conductive body and the glue melt diffuse to each other at high temperature, form a tight, dense, reliable and stable connection, and then cool the glue melt to form a strong and elastic protective layer, which can protect and strengthen the electrical connection interface between the conductive body and the conductive layer, ensure the stable connection of the force-sensitive sensing structure, and realize reliable measurement. In addition, when the force-sensitive electrode is used to prepare the force-sensitive sensing structure, the material and related process of the resistance layer can be saved, and the toughness, stability and reliability of the entire force-sensitive sensing structure and even the flexible pressure sensor can be improved, so that the flexible pressure sensor can function stably and reliably for a long time under complex conditions.

[0010] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0012] Figure 1 is a first perspective structural schematic view of a force-sensitive sensing structure provided by an embodiment of the present application; Figure 2 is a second perspective structural schematic view of a force-sensitive sensing structure provided by an embodiment of the present application; Figure 3 is a structural schematic view of a force-sensitive sensing structure provided by an embodiment of the present application; Figure 4 is a sectional structural schematic view of a first electrode line provided by an embodiment of the present application; Figure 5 is a structural schematic view of a flexible pressure sensor provided by an embodiment of the present application; Figure 6 is an exploded schematic view of a flexible pressure sensor provided by an embodiment of the present application; Figure 7 is a sectional structural schematic view of a flexible pressure sensor provided by an embodiment of the present application; Figure 8 is Figure 7 is a partial structural schematic view of the structure shown in FIG. 8; Figure 9is a structural schematic diagram of a first base layer provided by an embodiment of the present application; Figure 10 is a structural schematic diagram of a second base layer provided by an embodiment of the present application; Figure 11 is a step flow schematic diagram of a manufacturing method of a force-sensitive electrode provided by an embodiment of the present application Figure 12 is a structural schematic diagram of a conductive wire and stranding jig provided by an embodiment of the present application; Figure 13 is a structural schematic diagram of the stranding jig of the structure shown in Figure 12 is a structural schematic diagram of another view of the stranding jig of the structure shown in Figure 14 is a step flow schematic diagram of a conductive layer laying method provided by an embodiment of the present application; Figure 15 is a structural schematic diagram of a conductor, an extruding device and a traction device provided by an embodiment of the present application; Figure 16 is a step flow schematic diagram of a manufacturing method of a flexible pressure sensor provided by an embodiment of the present application.

[0013] Reference signs: X, first direction; Y, second direction; Z, preset direction 100, force-sensitive sensing structure; 200, flexible pressure sensor; 10, first electrode line; 11, first conductor; 111, first conductive wire; 112, stranding part; 12, first conductive layer; 20, second electrode line; 21, second conductor; 22, second conductive layer; 30, first base layer; 40, second base layer; 50, insulating layer; 51, through region; 52, connection point; 61, stranding jig; 611, strand passage; 62, extruding device; 621, extruding die; 622, wire core passage; 63, traction device.

[0014] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and are not limiting to the present application. DETAILED DESCRIPTION

[0015] With reference to the drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts are within the scope of the present application.

[0016] The flowcharts shown in the drawings are only illustrative, and do not necessarily include all contents and operations / steps, nor are they necessarily executed in the order described. For example, some operations / steps can be further decomposed, combined or partially merged, so that the actual execution order can be changed according to actual situations.

[0017] It should be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and the appended claims of the present application, unless otherwise clearly indicated by the context, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0018] It should be understood that, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, the terms "first", "second", etc. are used to distinguish the same or similar items with basically the same functions and effects. For example, the first data and the second data are only used to distinguish different data, and do not limit the order. Those skilled in the art can understand that the terms "first", "second", etc. do not limit the quantity and execution order, and the terms "first", "second", etc. also do not necessarily mean different.

[0019] It should be further understood that the term "or" used in the specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0020] Some embodiments of the present application will be described in detail below with reference to the drawings. The following embodiments and features in the embodiments can be combined with each other without conflict.

[0021] With the vigorous development of robot technology, intelligent cockpit technology and wearable technology, new products such as robot electronic skin and intelligent seats are gradually opening up the market, and there are also a large number of new pressure sensing interaction needs. Because the surface of electronic products such as robots, intelligent seats, wearable electronic devices, etc. often has a complex form, some robot fingers also have flexible dynamic curved surfaces, and traditional rigid force sensing sensing structures based on metal strain gauges and silicon-based MEMS are difficult to achieve good contact and measurement. Especially for soft surfaces and complex curved surfaces, pressure measurement devices often need to have both large-area array and good conformal fitting ability. For rigid force sensing structures, once a large-area array is formed, not only will the mechanical structure be more fragile, but also it will be difficult to maintain stable and reliable conformal fitting with soft surfaces or complex curved surfaces at all times, and thus it will be difficult to accurately and reliably measure the pressure of complex contact interfaces in scenarios such as changes in the sitting posture of passengers on soft intelligent seats, and robots sensing and assembling electronic components through electronic skin.

[0022] Please refer to WO2023050639A1 and CN220670763U, the related technology provides a piezoresistive layer and provides a flexible pressure sensor, which includes a first electrode layer, a piezoresistive layer laminated on the first electrode layer, and a second electrode layer laminated on the piezoresistive layer, forming a sandwich type flexible pressure sensing structure. Specifically, when the flexible pressure sensor is pressed, the piezoresistive layer can be compressed in the thickness direction, and the internal conductive network also increases the lap joint point density due to vertical displacement, thereby forming good conformal fitting and a large number of measurement electrical connection contact points on the flexible pressure surface, and achieving accurate and reliable pressure measurement. After unloading, each layer can return to the original state, the electrical connection contact points decrease, and the resistance returns. On this basis, the conductive lines on the first electrode layer and the conductive lines on the second electrode layer can be crossed, so that the conductive lines almost cover the entire surface of the pressure sensing layer. The pressure sensing layer can sense the pressure applied at each place on the surface and transmit it in the form of a resistance value signal, thereby improving the accuracy of pressure detection.

[0023] However, the inventors found that the related technology, due to the design of the piezoresistive film layer, in the first aspect, the piezoresistive film layer and the first electrode layer and the second electrode layer are still essentially two independent objects, and need to be electrically connected by contact. Long-term use can easily cause the contact stability and reliability to decrease due to friction and stretching. If fixed by adhesion, firstly, it is difficult to control the solidification strength in the process, and then the range, sensitivity and linearity of each contact point are different, and the measurement result is unreliable. Secondly, the adhesive layer is also easy to delaminate under long-term friction and stretching. Especially in the use environment of smart seats, smart beds and the like, the adhesive layer is easy to produce glass cracking. Once the bonding strength or microstructure of the adhesive layer changes, the range, sensitivity and linearity of the related contact points are difficult to guarantee, and even direct open circuit failure.

[0024] In the second aspect, the use environment of the seat, the smart bed and the like is coupled with the influence of body temperature and air humidity. The piezoresistive film layer and the possible adhesive layer are easy to penetrate water vapor to the conductive interface after absorbing moisture, causing metal line electrochemical corrosion, forming insulating corrosion products, causing unstable measurement, and even partial contact point failure.

[0025] In the third aspect, the piezoresistive film layer substrate is often a fiber with a certain elasticity. The conductive fiber and the piezoresistive film layer have weak bonding ability. After multiple cycles, interface slip, stress relaxation and permanent deformation and other problems are easy to occur, the resistance baseline changes, and the zero point drift is not recoverable. Long-term use is also easy to cause Joule heat, accelerate the aging of the substrate and even breakdown, and shorten the service life of the sensor.

[0026] In the fourth aspect, the piezoresistive film layer itself is expensive and has high cost. If it is arranged between the first electrode layer and the second electrode layer, long-term use is also easy to cause problems such as moisture absorption, edge opening, displacement and tensile creep, affecting the accurate measurement of the pressure signal.

[0027] To solve the above problems, the application provides a force-sensitive sensing structure 100, please refer to Figure 1 and Figure 2 The force-sensitive sensing structure 100 can include a first electrode line 10 and a second electrode line 20. The first electrode line 10 can include a first conductive body 11 and a first conductive layer 12. The first conductive layer 12 can be coated on the first conductive body 11 and electrically connected with the first conductive body 11. The second electrode line 20 can include a second conductive body 21. It should be understood that the first electrode line 10 can also be referred to as a force-sensitive electrode, and the second electrode line 20 can also be referred to as a conductive electrode. The first conductive body 11 and the second conductive body 21 can both be a conductive body.

[0028] Specifically, the first conductive layer 12 can be applied to the first conductive body 11 by coating, wrapping, extruding or the like, and electrically connected to the first conductive body 11 to form the first electrode line 10. It should be understood that by applying the first conductive layer 12 to the first conductive body 11, a stable, continuous, dense and thickness-controllable first conductive layer 12 can be formed on the outer surface of the first conductive body 11, and the separate-gluing / contacting interface is converted into an integrated-conformal interface. Moreover, when the first conductive layer 12 is applied to the first conductive body 11 by extrusion, the molten first conductive layer 12 colloid can diffuse with the surface layer of the first conductive body 11 under the action of pressure, and form a stable and reliable micro-network structure after cooling, thereby protecting the electrical connection interface between the conductive layer and the conductive body and further enhancing the interface bonding strength, eliminating the problems of slippage and delamination from both macroscopic and microscopic structures.

[0029] In some embodiments, at least a portion of the second electrode line 20 can be arranged in overlap with the first electrode line 10 and electrically connected to the first electrode line 10 through the first conductive layer 12. It should be understood that the overlapping area of the second electrode line 20 and the first electrode line 10 can form a force-sensitive sensing measurement node. By overlapping the second electrode line 20 with the first electrode line 10 and tightly and reliably applying the first conductive layer 12 to the first conductive body 11, the first electrode line 10 and the second electrode line 20 no longer need to insert an additional pressure-resistance film or a glue layer which is prone to drift and unreliable contact, but directly realize electrical connection through the surface of the first conductive layer 12. When external pressure acts on the overlapping area, the first conductive layer 12 is elastically compressed, the distance between the internal conductive particles is reduced, the effective conductive path is increased, and the node resistance is lowered; after unloading, the first conductive layer 12 rebounds, the conductive network returns to the original loose state, and the resistance rises. This avoids the problems of contact drift, unreliable circuit and the like caused by slippage, delamination, delamination or moisture absorption of the traditional pressure-resistance layer and sandwich structure, and eliminates the possible electrical signal delay caused by the gluing process, so that the force-sensitive sensing measurement node still maintains the consistency and reliability of the range, sensitivity and linearity in the application environment of long-term frequent bending, stretching, friction, moisture and temperature changes.

[0030] It should be understood that the resistance of at least a portion of the first conductive layer 12 can change with the change of the external force. Since in the flexible pressure sensor 200, the commonly used measurement point area is only a part of the entire flexible pressure sensor 200 layout area, and the other part is only used for wiring and signal transmission. In some large-area and high-density array force-sensitive sensing structures 100 applications, in order to ensure that there is no cross-talk, interference and short circuit between the wiring and signal transmission lines, a part of the first conductive layer 12 can be insulated, and the resistance of a part can change with the change of the external force.

[0031] Further, the first conductive layer 12 with insulation properties can be applied to the first conductive body 11 in a manner different from the first conductive layer 12 with force sensing properties. For example, the first conductive layer 12 with insulation properties can be applied to the first conductive body 11 by wrapping or coating, and the first conductive layer 12 with force sensing properties can be applied to the first conductive body 11 by extrusion.

[0032] In some embodiments, the first conductive body 11 can be arranged to extend in a first direction, and the second electrode line 20 can be arranged to extend in a second direction. The second direction and the first direction can be arranged at an angle. The absolute value of the angle between the first direction and the second direction can be 30°-90°. Typically but not limitedly, the absolute value of the angle between the first direction and the second direction can be 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, or any range formed by any two values.

[0033] In some embodiments, referring to Figure 3 , the second electrode line 20 can further include a second conductive layer 22, the second conductive layer 22 being applied to the second conductive body 21, and the second conductive layer 22 being electrically connected to the second conductive body 21. At this time, the second electrode line 20 can also be referred to as a force sensing electrode. Specifically, the first conductive layer 12 can be applied to the first conductive body 11 by extrusion, wrapping or coating. Alternatively, the second conductive layer 22 can be applied to the second conductive body 21 by extrusion, wrapping or coating. It should be understood that the first conductive layer 12 and the second conductive layer 22 are both a conductive layer.

[0034] Further, the resistance of at least a portion of the second conductive layer 22 can change with the change of the external force. It should be understood that the second conductive layer 22 can be conformally applied along the outer surface of the second conductive body 21 to form a force sensing conductive structure symmetrical to the first conductive layer 12. Through the design of the double-layer conductive layer, the single-point effective sensing area is expanded, the measurement reliability is improved, the mutual redundancy is realized, the single-point failure risk is reduced, and long-term stable electrical connection and pressure detection are realized.

[0035] In some embodiments, the conductive layer can be formed by using a gum base and a conductive filler. For example, the first conductive layer 12 can include a gum base and a conductive filler. For another example, the first conductive layer 12 can be a conductive soft rubber doped with a conductive filler. For another example, the second conductive layer 22 can include a gum base and a conductive filler. For another example, the second conductive layer 22 can be a conductive soft rubber doped with a conductive filler. It should be understood that a continuous and stable elastic matrix network can be provided by the gum base, and the conductive filler forms a percolation channel in the matrix. When an external force acts on the overlapping area, the gum base reduces the filler spacing through elastic compression, the percolation network density increases, and the macroscopic resistance decreases, realizing force resistance conversion. Moreover, since the gum base and the conductive filler are combined by intermolecular forces and physical doping, no additional adhesive is needed, eliminating the risk of interface slip, wear short circuit and delamination in the traditional sandwich structure. At the same time, the gum base can be doped with other fillers, which helps to improve the material structure and mechanical strength of the gum base by adjusting the composition of the gum base, so that it can be flexibly adapted to various environments such as seats and mattresses, ensuring long-term stable rubber state, ensuring that the resistance value of the conductive layer changes reversibly, the range is stable, and the form is reliable under long-term bending, stretching, compression cycles, so as to realize the long-term stable operation of the force-sensitive sensing structure 100.

[0036] It should be further understood that, due to the design of the gum base, the cross-over arrangement between the second electrode wire 20 and the first electrode wire 10 can realize high-adhesion elastic contact without additional adhesive, and the gum base generates local micro-flow under pressure, automatically fills the micro-uneven surface, forms a continuous and effective conductive path, significantly reduces the contact resistance, and can also expand the effective contact area, disperse local stress, and improve wear resistance. In addition, the flexibility and stretchability of the gum base enable the overlapping area to maintain good electrical connection stability when subjected to composite external forces such as stretching, bending or shearing, adapt to complex curved surface application environments such as intelligent seats and mattresses, and ensure long-term reliable electrical connection between the first electrode wire 10 and the second electrode wire 20.

[0037] In some embodiments, the conductive filler can include at least one of a conductive polymer, graphite, carbon black, metal powder and a conductive salt. Among them, the carbon-based dopant such as graphite and carbon black can also include carbon nanotubes, conductive graphite, graphene, etc. The conductive polymer can include polyaniline, polythiophene, PEDOT, PSS, etc. The metal powder can include silver-coated copper, nickel powder, aluminum powder, etc. Lithium salt can also be added, and the gum base is a polyether matrix, thereby realizing ion conduction.

[0038] In some embodiments, the gum base can include at least one of TPU, PP, PE and PI, thereby improving the wear resistance and weather resistance of the electrode wire and the conductive layer.

[0039] In some embodiments, the ratio of the gel matrix to the conductive filler can range from 1:25 to 1:1, or the conductive soft glue can be doped with 2% to 50% of the conductive filler by total mass. In some embodiments, when the conductive soft glue is doped with less than 40% of the conductive filler by total mass, the high sensitivity of the force-to-resistance conversion effect can be ensured; when the conductive soft glue is doped with more than 15% of the conductive filler by total mass, dense percolation channels can be formed in the gel matrix, ensuring a high initial conductivity, strong resistance to electrochemical corrosion, and stable resistance under high load.

[0040] Typically but not limitedly, the proportion of the conductive filler doped in the conductive soft glue by total mass can be 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or a range value composed of any two numerical values. The mass ratio of the gel matrix to the conductive filler can be 1:25, 1:20, 1:15, 1:10, 1:5, 1:4, 1:3, 1:2, 1:1, or a range value composed of any two numerical values.

[0041] In some embodiments, the force sensing structure 100 can include a plurality of first electrode lines 10 and a plurality of second electrode lines 20. The plurality of first electrode lines 10 are arranged at intervals and extend in a first direction. The plurality of second electrode lines 20 are arranged at intervals and extend in a second direction, so that at least part of the plurality of second electrode lines 20 is arranged to overlap the plurality of first electrode lines 10 and is electrically connected to the plurality of first electrode lines 10 through the first conductive layer 12. It should be understood that each intersectional overlapping area between the first electrode lines 10 and the second electrode lines 20 can constitute a force sensing measurement node, or a certain force sensing measurement node and a plurality of force sensing nodes around it can form a force sensing measurement pixel unit. Each pixel unit can contain, for example, a 1*2, 2*2, 3*3, 3*2, 4*4, 5*5, etc. form of force sensing node array, which can be realized by adjusting the spacing between the electrode lines. It should be understood that since the sensing area of the force sensing in products such as seats, wearable devices, and robot electronic skins is not evenly distributed, by using a force sensing node array, the limited electrode lines can be used to arrange as many intersection points and contact points as possible in a specific sensing area, thereby saving costs and effectively improving the triggering sensitivity, range, and other performance. It should be further understood that since the range of a single force sensing node is limited, and the pressure distribution on the flexible dynamic interface is often in the form of a multi-peak surface, by arranging the electrode lines in rows and columns, a plurality of force sensing nodes can be concentrated and combined to form a pixel unit, which can facilitate the control algorithm to perform adaptive calibration and measurement of the sensitivity in the pixel unit and suppress interference and other operations. This includes being able to perform differential operation on the resistance of each node in a certain pixel unit, ensuring the linearity and reliability of the measurement of each node, and improving the pressure measurement resolution, accuracy, and total range in the pixel unit.

[0042] In some embodiments, the plurality of first electrode lines 10 can be a plurality of first electrode line 10 segments formed by a serpentine or corrugated trace in a local area, and the plurality of second electrode lines 20 can be a plurality of second electrode line 20 segments formed by a serpentine or corrugated trace in a local area. It should be understood that the trace method can ensure that the conductive layer is tightly wound with the substrate such as non-woven fabric, avoiding interface slippage caused by traditional printing or lamination. At the same time, the serpentine corrugated structure can provide a stretchable margin in the plane, and when the surface of the seat or mattress is subjected to tension, the trace can expand to absorb the strain and reduce the risk of conductive layer fracture.

[0043] In some embodiments, please refer to Figure 4The conductive body can include a plurality of conductive filaments, thereby enhancing the electrical stability and mechanical structural reliability. For example, the first conductive body 11 can include a plurality of first conductive filaments 111, and the plurality of first conductive filaments 111 are connected by at least one of winding, twisting, pressing and welding. For another example, the second conductive body 21 includes a plurality of second conductive filaments, and the plurality of second conductive filaments are connected by at least one of winding, twisting, pressing and welding. It should be understood that, on the one hand, the plurality of conductive filaments are formed into an integrated filament bundle structure by winding, twisting, pressing or welding, which can provide parallel conductive paths in the same cross-sectional area and reduce the risk of resistance sudden change caused by single filament breakage. For example, when the local filament material appears fatigue fracture due to repeated bending, the remaining complete filament bundle still maintains macroscopic electrical continuity, thereby enhancing the electrical stability. On the other hand, the filament bundle structure can slide relative to each other under tensile and torsional load, thereby dispersing mechanical stress, reducing permanent deformation and enhancing the fatigue life of the flexible sensor. On the other hand, the uneven surface of the filament bundle mechanically interlocks with the conformally deposited conductive layer, thereby increasing the interfacial peeling strength, further inhibiting interlayer sliding and ensuring that the resistance curve of the force-sensitive sensing structure 100 is stable and reliable during long-term use. It should be understood that the first conductive filaments 111 and the second conductive filaments are both a kind of conductive filament.

[0044] In some embodiments, the first conductive body 11 can include at least one of silver wire, copper wire, tinned copper, stainless steel wire and carbon fiber; or the second conductive body 21 can include at least one of silver wire, copper wire, tinned copper, stainless steel wire and carbon fiber. It should be understood that the silver wire has a conductive surface oxide layer, which can maintain low contact resistance in high humidity and high salt spray environment, and is suitable for headrest and lumbar support areas with strict requirements for signal stability; the copper wire has high electrical conductivity and low raw material cost, and can well undertake current transmission task and reduce the overall wire resistance; the carbon fiber has the characteristics of light weight, high strength and fatigue resistance, and after being twisted, the tensile strength and bending life of the filament bundle can be improved without significantly increasing the linear density, which is suitable for large-area distributed sensing array.

[0045] The force-sensitive sensing structure 100 provided by the embodiment of the present application can also achieve the following effects: first, by the overlapping and intersecting arrangement of the first electrode lines 10 and the second electrode lines 20, in the flexible pressure sensor 200, as long as a plurality of first electrode lines 10 and a plurality of second electrode lines 20 are arranged from different directions, the force-sensitive sensing structure 100 can be continuously copied and formed in a certain rule to form a large-area, high-density sensing and control point array, so as to measure the flexible interface of the skin, soft tissue, intelligent seat and intelligent bed; second, since the first electrode lines 10 and the second electrode lines 20 are flexible, they can be better conformally attached to the complex curved surface and the flexible interface on the basis of forming the array, avoiding poor contact and problems such as missed detection and false detection; third, since the first conductive layer 12 is laid on the first conductive body 11, the mechanical contact and electrical contact between the first conductive layer 12 and the first conductive body 11 achieve high reliability and high stability, when the force-sensitive sensing structure 100 is subjected to external force, the stress of the first conductive layer 12 can be naturally changed, and the resistance value of the first conductive layer 12 is also changed, on the basis of which, since the second conductive body 21 is electrically connected with the first electrode line 10 through the first conductive layer 12, the current value between the second conductive body 21 and the first conductive body 11 is also changed, realizing stable and reliable pressure measurement. In addition, the conductive wires of different materials can be mixed in a certain proportion, or copper can be plated on the carbon fibers, so as to improve the conductive performance and mechanical structural strength.

[0046] The embodiment of the present application provides a flexible pressure sensor 200, which can include the force-sensitive sensing structure 100 provided by any embodiment of the present application. Specifically, please refer to Figure 5 to Figure 7 The flexible pressure sensor 200 can include a first base layer 30 and a second base layer 40, and the forms of the first base layer 30 and the second base layer 40 can change according to the change of external force. It should be understood that, since the first base layer 30 and the second base layer 40 are flexible, they can be better conformally attached to the flexible and dynamic interface for pressure measurement.

[0047] In some embodiments, please refer to Figure 9 and Figure 10The plurality of first electrode lines 10 can be arranged at intervals on the first base layer 30, and the plurality of second electrode lines 20 can be arranged at intervals on the second base layer 40. The first base layer 30 and the second base layer 40 are arranged oppositely, so that at least part of the second electrode lines 20 is arranged to overlap the first electrode lines 10, and at least part of the second electrode lines 20 is electrically connected to the first electrode lines 10 through the first conductive layer 12. It should be understood that through the first base layer 30 and the second base layer 40, not only can the force-sensitive sensing structure 100 be easily arranged in an array through the wiring design of the electrode lines on the base layer, but also a stable setting framework can be provided for the force-sensitive sensing structure 100, so as to ensure the stability of the relative position and prevent problems such as short circuit and crosstalk of the electrode lines. Specifically, the electrode lines can be arranged on the base layer by means of adhesion, threading, flat weaving, rope embroidery, and embroidery.

[0048] Specifically, the material of the first base layer 30 can include cloth, and the plurality of first electrode lines 10 are embroidered on the first base layer 30. In addition, the material of the second base layer 40 includes cloth, and the plurality of second electrode lines 20 are embroidered on the second base layer 40. It should be understood that, on the one hand, the electrode lines are formed on the base layer by the embroidery process, and the electrode lines can be directly sewn into the fabric according to the design pattern, and the electrode lines and the cloth base form mechanical interlocking, which not only controls the in-plane position tolerance of the electrode lines, but also avoids the problems of glue creep and debonding caused by traditional adhesion. On the other hand, the embroidered area can retain the original breathable and foldable characteristics of the fabric, and does not increase the additional hardness when conformally attached to flexible interfaces such as seats and mattresses. Furthermore, since the cloth base and embroidery design are adopted, after the electrode lines are embroidered on the first and second base layers 40 respectively, the two layers of cloth can be simply aligned and pressed together to automatically align the cross-over nodes, and high-precision laminating equipment is not required. In addition, both electrode lines can be restrained by the cloth base, and the cloth bases can be easily restrained by embroidery, so that the electrode lines are not easily displaced or shifted under repeated bending and stretching, thereby fundamentally reducing the risk of short circuit and signal crosstalk of the electrode lines. In addition, since the positioning accuracy and strength provided by embroidery are stronger than those of adhesion, mass production is easier to achieve. Therefore, the cross-arrangement layout of the two base layers and the electrode lines can be matched, and a high-reliability and scalable array force-sensitive sensing structure 100 setting scheme can be provided for the flexible pressure sensor 200. The cloth can include at least one of tie-dyed flat-woven cloth, spunlace cloth, needle-punched cloth, white peach cloth, and non-woven cloth.

[0049] In some embodiments, the flexible pressure sensor 200 further comprises an insulating layer 50 disposed between the first substrate layer 30 and the second substrate layer 40. The insulating layer 50 can shield a portion of the first electrode lines 10 and a portion of the second electrode lines 20, so that the portion of the second electrode lines 20 is isolated from the portion of the first electrode lines 10. It should be understood that, in addition to being used to form the force-sensitive sensing structure 100, the first electrode lines 10 and the second electrode lines 20 also need to have a portion to bear the role of signal transmission. If the electrode line segments for signal transmission are accidentally contacted, it is easy to introduce a current path and cause short circuit or crosstalk. Therefore, by placing the insulating layer 50 between the two substrate layers, and then opening a window for the target measurement area used to form the force-sensitive sensing structure 100 and covering the wiring area used for signal transmission with the insulating layer 50, only the first conductive layer 12 and the second conductive layer 22 at the windowed part are allowed to directly contact to form a connection point 52, and the remaining segments are physically isolated by the insulating layer 50 to block crosstalk current. The force-resistance conversion characteristics at the force-sensitive sensing structure 100 are maintained, and the row and column lines are ensured to be electrically insulated from each other when performing signal transmission or current transmission at other positions, effectively reducing the risk of noise coupling and false triggering, and improving the integrity and reliability of the array sensing signal.

[0050] Specifically, please refer to Figure 7 and Figure 8 The insulating layer 50 can be provided with a through region 51, at least a portion of the plurality of second electrode lines 20 is electrically connected to the plurality of first electrode lines 10 through the through region 51, and a plurality of connection points 52 are formed in the through region 51. It should be understood that, by forming a plurality of connection points 52 in the through region 51, the measurement sensitivity and accuracy can be improved, and the force-sensitive sensing measurement can be stable and reliable. Specifically, the plurality of connection points 52 can also be combined to form a 5*5, 3*4, or other multi-array type pixel unit, to further improve the measurement range, sensitivity, and accuracy.

[0051] The inventors have found that if the resistance layer is simply wrapped and laid on the conductive body, displacement and wear will still occur between the resistance layer and the conductive body during long-term use. On the one hand, the interface between the two lacks molecular interdiffusion, and only relies on mechanical wrapping or adhesive fixation. Under the action of periodic bending, stretching, or shearing stress, interface shear stress concentration causes micro-slip, resulting in a gradual decrease in the contact points between the conductive layer and the conductive body and a gradual increase in the contact impedance. On the other hand, the elastic modulus of the resistance layer substrate is usually lower than that of the conductive body. After repeated deformation, the substrate stress relaxes, the wrapping layer loosens, and local voids appear, further exacerbating wear and generating abrasive debris, which is trapped between the interface to form insulating islands, easily causing signal jump and zero drift, and other problems. In addition, the slip process is sometimes accompanied by concentrated Joule heat, which accelerates the aging of the substrate, makes the resistance layer brittle and cracked, and eventually loses the force-resistance conversion ability.

[0052] To solve the above problems, the application provides a manufacturing method of a force-sensitive electrode, and the manufactured force-sensitive electrode can be used in the force-sensitive sensing structure 100 of any embodiment of the application. It can be understood that the first electrode wire can be referred to as a force-sensitive electrode, and therefore, the manufacturing process of the first electrode wire 10 is taken as an example for introduction below. In the related drawings, the force-sensitive electrode can correspond to the first electrode wire 10, the conductive body can correspond to the first conductive body 11, the conductive wire can correspond to the first conductive wire 111, and the conductive layer can correspond to the first conductive layer 12. Please refer to Figure 4 and Figure 11 , Figure 11 The manufacturing method of the force-sensitive electrode provided in an embodiment of the application can include steps S101 to S103, and specifically can include the following steps. S101, providing a conductive body and a glue melt.

[0053] The conductive body is in a wire shape.

[0054] In some embodiments, the conductive body can include a plurality of conductive wires, and specifically, a plurality of conductive wires can be provided; and the plurality of conductive wires can be processed by at least one of winding, twisting, pressing and welding, so as to obtain the conductive body. It should be understood that the toughness and mechanical structural strength of a single conductive body are often not as good as those of a wire bundle structure. By processing the plurality of conductive wires by at least one of winding, twisting, pressing and welding, the structural strength and toughness of the conductive body can be strengthened, so as to better adapt to the application scenarios such as aerospace and intelligent cockpit with complex temperature and humidity conditions.

[0055] In some embodiments, the way of providing the plurality of conductive wires can include providing a plurality of wire rolls; arranging the plurality of wire rolls on a plurality of spool mechanisms; and rotating the wire rolls to obtain the plurality of conductive wires. It should be understood that the plurality of conductive wires can be released synchronously by rotating the wire rolls, and the plurality of conductive wires can be fed in parallel under constant tension, so as to avoid subsequent defects such as twisted strand loosening or pressing caused by uneven tension. Further, a controller such as a magnetic hysteresis brake can be configured on the spool mechanism to reduce the tension fluctuation of the wire bundle, and to ensure the consistency of the roundness of the wire bundle and the cross-sectional area of the conductive body. The plurality of conductive wires after unwinding can be gathered by a guide wheel and enter a twisting jig or a pressing mold cavity. The planetary twisting head can be used for twisting, and the pitch and twisting direction can be adjusted to periodically displace each wire in the length direction and disperse the bending stress. By the continuous process of unwinding-twisting / pressing under tension control, the conductive body with high mechanical strength, high bending fatigue life and uniform electrical conductivity can be obtained, so as to meet the long-term reliable application requirements in the temperature and humidity alternating environment of aerospace and intelligent cockpit.

[0056] In some embodiments, please refer to Figure 12 and Figure 13 , Figure 12 is a structural schematic diagram of a conductive wire and a twisting jig provided in an embodiment of the application,Figure 13 for Figure 12 This is a schematic diagram of the stranding fixture from another perspective. As shown, a conductor can be obtained by stranding multiple conductive wires. Specifically, a stranding fixture 61 can be provided; multiple conductive wires are threaded through multiple strand channels 611, with at least a portion of the multiple conductive wires passing through the multiple strand channels 611; the portions of the multiple conductive wires passing through the multiple strand channels 611 are stranded or wrapped to obtain a conductor, which has a stranded portion 112. The stranding fixture 61 can have multiple strand channels 611. It should be understood that the design of the strand channels 611 can bind multiple conductive wires to the same axis, preventing slippage, eccentricity, uneven conductive layer, and other problems. The stranded portion 112 formed by the conductor can continuously pull the stranded wire and control the direction of the stranded wire, avoiding severe friction between the conductive wires and the sidewalls of the strand channels 611.

[0057] It should be further understood that the formation of the stranded portion 112 provides a mechanically strong working object for subsequent traction and winding processes, ensuring stable, efficient, and high-yield traction and winding processes. Specifically, the stranded portion 112 can naturally form through holes, or it can provide a certain mechanical strength and be wound around the traction head of the traction device 63, ensuring smooth and stable movement of the conductor, uniform extrusion of the conductive layer, and preventing uneven conductive layer setting due to directional deviation of some conductive wires, or even problems such as cracks in the conductive layer or exposure of conductive wires.

[0058] S102. Apply the molten adhesive onto the conductor to form a conductive layer.

[0059] The resistance of the conductive layer changes with the external force applied to it.

[0060] In some embodiments, multiple conductive wires can be twisted together to form a conductor, and the conductor can have a twisted portion 112 formed. The twisted portion 112 can be wound around a winding mechanism, and the winding mechanism can straighten and pull the twisted portion 112 to move. The molten adhesive can be extruded and applied to the conductor. Finally, after cooling the conductor and the conductive layer, the winding mechanism can be used to wind up the cooled conductor and the conductive layer.

[0061] It should be understood that since the conductive wires and conductors are generally made of metal, and the force-sensitive electrodes are often quite thin, if the conductive wires or conductors shift off-center, it can easily cause some of them to be exposed to the air or result in uneven distribution of the conductive layer, leading to technical problems such as short circuits. This directly causes the measurement results of the relevant force-sensitive sensing structure 100 to be unreliable and insensitive, and may even lead to the risk of short circuits and overheating during measurement.

[0062] Therefore, by extruding the glue melt on the conductor while the coiling mechanism straightens and pulls the twisted part 112, the pulling and extruding can be performed simultaneously, the effect of the pulling direction of the pulling device 63 is fully utilized, and the extruding device 62 is cooperated through the control of the pulling speed, the extruding speed of the glue melt or the flow control of the extruding device 62 is adapted to different components, so that the conductor layer is uniformly laid and the conductor is not eccentric. In addition, the arrangement of the coiling mechanism can also help the force-sensitive electrode to be well stored, transported and stored, and the manufactured force-sensitive electrode can be easily transferred to the related production line of the flexible pressure sensor 200 for embroidering and assembling production.

[0063] In some embodiments, the glue melt can be formed into a conductive layer by extruding and laying the glue melt on the conductor. It should be understood that, due to the adoption of the extruding and laying process of the glue melt, the conductive layer conforming to the conductor can be continuously and stably formed on the surface of the conductor, which is suitable for batch production. In addition, during the extruding process, the glue melt can be in a viscous flow state under the action of high temperature and shearing, the molecular chain segments and the metal atoms or oxide layer of the conductor surface can be mutually diffused and physically adsorbed, and a high-strength and high-toughness electrical connection interface can be formed after subsequent cooling treatment, which has the dual effects of thermal expansion and contraction locking and microstructure adsorption, can effectively prevent relative slipping and separation in subsequent use, and ensures the stability and reliability in long-term use. In addition, due to the absence of an additional glue layer at the interface, the internal stress caused by the difference in the coefficient of thermal expansion between the conductive layer and the conductor is low, which can maintain stable electrical connection and mechanical properties under high temperature, high humidity and repeated bending conditions, and meet the long-term reliable operation requirements of the flexible pressure sensor 200.

[0064] In some embodiments, the extruding and pulling can be realized by the cooperation of the extruding device 62 and the pulling device 63, which can be two parts of the same device or different devices. Please refer to Figure 14 and Figure 15 , Figure 14 a step flow diagram of a conductive layer laying method provided by an embodiment of the present application, Figure 15 a structural diagram of a conductor, an extruding device and a pulling device provided by an embodiment of the present application, and the conductive layer laying method can specifically include steps S102a to S102c.

[0065] S102a, providing an extruding device 62 and a pulling device 63.

[0066] The extruding device 62 can include a wire core channel 622 opened along a predetermined direction.

[0067] It should be understood that by keeping the core channel 622 direction of the extrusion device 62, the pulling movement direction, and the strand channel 611 direction consistent as the preset direction, it is ensured that the conductive wire always moves along the same axis during processing, avoiding uneven thickness of the conductive layer or disordered filler orientation caused by bending or twisting.

[0068] S102b, at least a part of the conductor is passed through the core channel 622, and the conductor passing out of the core channel 622 is connected to the pulling device 63.

[0069] It should be understood that the constant tension provided by the pulling device 63 keeps the conductor straight in the extrusion cavity, which is beneficial to the uniform coating of the glue melt in the circumferential direction, forming a concentric and thickness-controllable conductive layer; at the same time, the pulling device 63 can adjust the moving direction and eliminate the lateral force, reducing the friction between the conductive wire and the cavity wall, reducing the risk of surface scratching and wire breaking, thereby ensuring the consistency of the electrical properties and structural integrity of the force-sensitive electrode in continuous mass production.

[0070] S102c, the conductor is pulled by the pulling device 63 to move along the preset direction, and the glue melt is extruded and laid on the conductor by the extrusion device 62.

[0071] It should be understood that due to the cooperative configuration of the pulling device 63 and the extrusion device 62, the conductive wire only needs to be twisted at one end at the beginning, and the subsequent wire segments can be automatically arranged in close parallel through the process of glue melt extrusion and cooling, without twisting everywhere, greatly improving the manufacturing simplicity of the force-sensitive electrode.

[0072] Specifically, the extrusion device 62 can be provided with an extrusion die head 621, and the core channel 622 can be formed in the extrusion die head 621 along the preset direction. When the glue melt is extruded and laid on the conductor, the conductor can be specifically passed through the core channel 622 and moved along the preset direction; at least a part of the extrusion die head 621 is heated, and the glue melt is extruded and laid on the conductor through the extrusion die head 621. It should be understood that by keeping the conductor always located at the center of the core channel 622 during movement, the glue melt can be heated to a viscous flow state, reducing the melt viscosity, and ensuring that it forms a uniform annular coating at the die lip outlet of the extrusion die head 621. Further, the internal flow channel of the die head can also be designed with a taper, so that the melt realizes laminar flow attachment on the surface of the conductor, avoiding uneven distribution of fillers caused by turbulent flow; at the same time, the die lip temperature can be slightly lower than the melt temperature, which promotes the rapid surface drying of the outer layer, reduces the thickness fluctuation caused by subsequent pulling and stretching. Through co-extrusion, the glue melt and the conductor complete the electrical connection interface diffusion and coating at the same axis and the same speed, forming a concentric, dense and thickness-continuous conductive layer, ensuring that the force-sensitive electrode has uniform force-resistance characteristics along the length direction.

[0073] S103, cooling the conductive body and the conductive layer to obtain the force-sensitive electrode.

[0074] It should be understood that the cooling of the conductive body and the conductive layer can include at least one of water cooling, air cooling and natural cooling.

[0075] In some embodiments, the process of cooling the conductive body and the conductive layer can include: fire treatment of the conductive body and the conductive layer; water cooling of the conductive body and the conductive layer. It should be understood that the fire treatment can include short-time heating of the outer surface of the extrusion-coated conductive layer by using fire, infrared or hot air, so that the surface layer temperature is slightly higher than the melt temperature for a moment, so as to promote the relaxation of the surface layer molecular chain and eliminate the internal stress caused by shear orientation; then the water cooling treatment can be performed, and the surface layer is rapidly cooled by a cooling water bath or spraying, so as to form a dense and defect-free, elastic and tough surface layer, thereby preventing thickness fluctuation caused by subsequent traction stretching.

[0076] The manufacturing method of the force-sensitive electrode provided in an embodiment of the present application can achieve the following effects: by the method of applying the glue melt on the conductive body and cooling the conductive body and the conductive layer, the molecular diffusion between the conductive body and the glue melt at high temperature is realized, so as to form a tight, dense, reliable and stable connection; then the cooling treatment of the glue melt can form a strong and elastic protective layer, which can protect and strengthen the electrical connection interface between the conductive body and the conductive layer, so as to ensure the stable connection of the force-sensitive sensing structure 100 and realize reliable measurement. In addition, when the force-sensitive electrode is used to prepare the force-sensitive sensing structure 100, the material and related process of the resistance layer can be saved, and the toughness, stability and reliability of the entire force-sensitive sensing structure 100 and even the flexible pressure sensor 200 are improved, so as to ensure the long-term stable and reliable function of the flexible pressure sensor 200 under complex conditions. By using the glue melt application process and cooling treatment, the molten conductive glue diffuses with the surface layer molecular chain of the conductive body under the action of pressure, and forms an interpenetrating network after cooling and solidification, which greatly improves the interface peeling strength, fundamentally eliminates the displacement and wear hazards, and ensures that the force-sensitive electrode, the force-sensitive sensing structure 100 and the flexible pressure sensor 200 remain stable and reliable under complex dynamic load.

[0077] The embodiment of the present application also provides a force-sensitive electrode, and the manufacturing method of the force-sensitive electrode can include the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application.

[0078] The embodiment of the present application also provides a manufacturing method of a flexible pressure sensor 200, which uses the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application, or the manufacturing method of the flexible pressure sensor 200 includes the manufacturing method of the force-sensitive electrode according to any one of the embodiments of the present application.

[0079] Referring to Figure 16 , Figure 16 A step flow diagram of a manufacturing method of a flexible pressure sensor according to an embodiment of the present application is provided. The manufacturing method of the flexible pressure sensor 200 can specifically include steps S201 to S204.

[0080] S201, providing a first substrate layer 30, a second substrate layer 40, a plurality of force-sensitive electrodes, and a plurality of conductive electrodes.

[0081] The first substrate layer 30 and the second substrate layer 40 are flexible, the force-sensitive electrode can include a conductor and a conductive layer, the conductive layer is laid on the conductor, and the resistance of the conductive layer changes with the change of the external force.

[0082] S202, the plurality of force-sensitive electrodes are arranged and disposed on the first substrate layer 30 along a first direction.

[0083] It should be understood that the plurality of force-sensitive electrodes can be arranged and disposed on the first substrate layer 30 by embroidery, rope embroidery, flat weaving, bonding, etc. Specifically, the plurality of force-sensitive electrodes can be embroidered on the first substrate layer 30, and the plurality of force-sensitive electrodes are arranged and disposed along the first direction.

[0084] S203, the plurality of conductive electrodes are arranged and disposed on the second substrate layer 40 along a second direction, and the second direction is arranged at an angle with the first direction.

[0085] It should be understood that the plurality of conductive electrodes can be arranged and disposed on the second substrate layer 40 by embroidery, rope embroidery, flat weaving, bonding, etc. Specifically, the plurality of conductive electrodes can be embroidered on the second substrate layer 40, and the plurality of conductive electrodes are arranged and disposed along the second direction.

[0086] S204, the first substrate layer 30 and the second substrate layer 40 are correspondingly arranged, so that a part of the plurality of force-sensitive electrodes and a part of the plurality of conductive electrodes are electrically connected, and the flexible pressure sensor 200 is obtained.

[0087] It should be understood that due to the design of the force-sensitive electrode and the conductive electrode, by correspondingly arranging the first substrate layer 30 and the second substrate layer 40, a part of the plurality of force-sensitive electrodes and a part of the plurality of conductive electrodes can be electrically connected to form a plurality of force-sensitive sensing structures 100, and the flexible pressure sensor 200 is obtained. The problems of easy displacement, poor contact, poor reliability, etc. in the traditional resistance layer design are avoided, the material loss and the process link are reduced, the cost is greatly reduced, and the complexity of the overall flexible pressure sensor 200 is reduced, so that it can be made more light and reliable.

[0088] However, the inventors find that if the first substrate layer 30 and the second substrate layer 40 are simply arranged correspondingly, a part of the plurality of force-sensitive structures and a part of the plurality of conductive electrodes can form a short circuit in the non-measurement area, causing a large amount of signal crosstalk and other problems.

[0089] In some embodiments, when the first substrate layer 30 and the second substrate layer 40 are arranged correspondingly to electrically connect at least a part of the plurality of force-sensitive electrodes and at least a part of the plurality of conductive electrodes, an insulating layer 50 is further provided and arranged between the first substrate layer 30 and the second substrate layer 40, so that the insulating layer 50 shields a part of the first electrode line 10 and a part of the second electrode line 20, and a part of the conductive electrode and a part of the force-sensitive electrode are isolated. Thus, the force-sensitive electrode and the conductive electrode in the non-measurement area are isolated to prevent crosstalk.

[0090] The present application also provides a flexible pressure sensor 200, a manufacturing method of the flexible pressure sensor 200 can include a manufacturing method of the force-sensitive electrode of any of the embodiments of the present application, or the flexible pressure sensor 200 includes the force-sensitive electrode of any of the embodiments of the present application, or the manufacturing method of the flexible pressure sensor 200 includes the manufacturing method of the flexible pressure sensor 200 of any of the embodiments of the present application.

[0091] The embodiments of the present application also provide an electronic device, which can include the force-sensitive sensing structure 100 of any of the embodiments of the present application, or the electronic device can include the flexible pressure sensor 200 of any of the embodiments of the present application. The electronic device can include the force-sensitive electrode of any of the embodiments of the present application, or the electronic device can include the flexible pressure sensor 200 of any of the embodiments of the present application, or the manufacturing method of the electronic device can include the manufacturing method of the force-sensitive electrode of any of the embodiments of the present application, or the manufacturing method of the electronic device can include the manufacturing method of the flexible pressure sensor 200 of any of the embodiments of the present application. The electronic device can include at least one of a wearable device, a robot, an electronic skin, a car seat, a flexible display screen, a medical bed, and an electronic toy. For example, the electronic device can be an electronic piano, and the force-sensitive sensing structure 100 can be arranged on the electronic piano to improve the sensitivity of the key surface of the electronic piano and achieve the tone and sound quality control like a real piano. For another example, the electronic device can be a car seat, and the flexible pressure sensor 200 or the force-sensitive sensing structure 100 can be arranged on the backrest and the cushion of the car seat to achieve the precise control of the passenger sitting posture detection and the airbag massage.

[0092] In the case of not contradicting each other, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples.

[0093] The above description is provided as an enabling teaching of the application and is not intended to limit its scope in any way. Any modification of the application in keeping with the spirit thereof and any further applications thereof within the technical field known to those skilled in the art are to be construed as falling within the purview thereof.

Claims

1. A method for manufacturing a force-sensitive electrode, characterized in that, include: A conductor and a molten adhesive are provided, wherein the conductor is linear; The adhesive melt is applied to the conductor to form a conductive layer, wherein the resistance of the conductive layer changes with the applied external force. The conductor and the conductive layer are cooled to obtain a force-sensitive electrode.

2. The method for manufacturing a force-sensitive electrode as described in claim 1, characterized in that, The provision of the conductor and the melt includes: Multiple conductive wires are provided; A conductor is obtained by processing the plurality of conductive wires by at least one of winding, twisting, pressing and welding.

3. The method for manufacturing a force-sensitive electrode as described in claim 2, characterized in that, The provision of multiple conductive wires includes: Multiple rolls of silk are available; The plurality of wire rolls are mounted on a plurality of spool mechanisms; Rotate to unwind, resulting in multiple conductive wires.

4. The method for manufacturing a force-sensitive electrode as described in claim 2, characterized in that, The process of twisting the multiple conductive wires includes: A stranding fixture is provided, wherein the stranding fixture has multiple strand channels; The plurality of conductive wires are threaded through the plurality of strand channels, and at least a portion of the plurality of conductive wires are threaded through the plurality of strand channels; The conductor is obtained by twisting or winding the portions of the multiple conductive wires that pass through the multiple strand channels, and the conductor has a twisted portion.

5. The method for manufacturing a force-sensitive electrode as described in claim 2, characterized in that, The conductor is obtained by twisting together the plurality of conductive wires, and the conductor has a twisted portion; The step of applying the molten adhesive onto the conductor includes: The twisted portion is wound onto the winding mechanism; The winding mechanism straightens and pulls the stranded part to move, and extrudes the molten adhesive onto the conductor. After the cooling process is performed on the conductor and the conductive layer, the following steps are included: The cooled conductor and the conductive layer are wound up by a winding mechanism.

6. The method for manufacturing a force-sensitive electrode as described in claim 1, characterized in that, The step of applying the molten adhesive onto the conductor to form a conductive layer includes: The molten adhesive is extruded and applied onto the conductor to form a conductive layer.

7. The method for manufacturing a force-sensitive electrode as described in claim 6, characterized in that, The step of extruding and applying the melt adhesive onto the conductor includes: An extrusion device and a traction device are provided, wherein the extrusion device includes a wire core channel opened along a predetermined direction; At least a portion of the conductor passes through the core channel, and the conductor exiting the core channel is connected to the traction device; The conductor is pulled along the preset direction by the traction device, and the melt is extruded and applied to the conductor by the extrusion device.

8. The method for manufacturing a force-sensitive electrode as described in claim 6, characterized in that, The extrusion device is provided with an extrusion die head, and the extrusion die head has a wire core channel opened along a preset direction; The step of extruding and applying the melt adhesive onto the conductor includes: The conductor is inserted through the wire core channel and moved along the preset direction; At least a portion of the extrusion die is heated, and the melt is extruded through the extrusion die and applied onto the conductor.

9. The method for manufacturing a force-sensitive electrode as described in claim 6, characterized in that, The cooling process for the conductor and the conductive layer includes: The conductor and the conductive layer are subjected to a fire treatment. The conductor and the conductive layer are subjected to water cooling.

10. A force-sensitive electrode, characterized in that, The method for manufacturing the force-sensitive electrode includes the method for manufacturing the force-sensitive electrode as described in any one of claims 1-9.

11. A method for manufacturing a flexible pressure sensor, characterized in that, The method for manufacturing the flexible pressure sensor uses the force-sensitive electrode as described in claim 10, or the method for manufacturing the flexible pressure sensor includes the method for manufacturing the force-sensitive electrode as described in any one of claims 1-9. or, The manufacturing method of the flexible pressure sensor includes: The system provides a first substrate layer, a second substrate layer, multiple force-sensitive electrodes, and multiple conductive electrodes. The first substrate layer and the second substrate layer are flexible. The force-sensitive electrode includes a conductor and a conductive layer. The conductive layer is laid on the conductor, and the resistance of the conductive layer changes with the applied external force. The plurality of force-sensitive electrodes are arranged at intervals along a first direction on the first substrate layer; The plurality of conductive electrodes are arranged at intervals along a second direction on the second substrate layer, wherein the second direction is at an angle to the first direction. By correspondingly configuring the first substrate layer and the second substrate layer, a portion of the plurality of force-sensitive electrodes is electrically connected to a portion of the plurality of conductive electrodes to obtain a flexible pressure sensor.

12. The method for manufacturing a flexible pressure sensor as described in claim 11, characterized in that, The step of correspondingly configuring the first substrate layer and the second substrate layer such that at least a portion of the plurality of force-sensitive electrodes is electrically connected to at least a portion of the plurality of conductive electrodes further includes: Provide insulation; The insulating layer is disposed between the first substrate layer and the second substrate layer; The insulating layer is used to shield a portion of the first electrode line and a portion of the second electrode line, thereby isolating a portion of the conductive electrode from a portion of the force-sensitive electrode.

13. The method for manufacturing a flexible pressure sensor as described in claim 12, characterized in that, The step of arranging the plurality of force-sensitive electrodes at intervals along a first direction on the first substrate layer includes: The plurality of force-sensitive electrodes are embroidered onto the first substrate layer and arranged at intervals along the first direction; Alternatively, the step of arranging the plurality of conductive electrodes at intervals along the second direction in the second substrate layer includes: The plurality of conductive electrodes are embroidered onto the second substrate layer and arranged at intervals along the second direction.

14. The method for manufacturing a flexible pressure sensor as described in claim 11, characterized in that, The step of stitching the plurality of force-sensitive electrodes onto the first substrate layer includes: The multiple force-sensitive electrodes are embroidered onto the first substrate layer by rope embroidery or embroidery. Alternatively, the plurality of conductive electrodes can be embroidered onto the second substrate layer, including: The multiple conductive electrodes are embroidered onto the second substrate layer using rope embroidery or needlework.

15. A flexible pressure sensor, characterized in that, The method for manufacturing the flexible pressure sensor includes the method for manufacturing a force-sensitive electrode as described in any one of claims 1-9; or, the flexible pressure sensor includes the force-sensitive electrode as described in claim 10; or, the method for manufacturing the flexible pressure sensor includes the method for manufacturing a flexible pressure sensor as described in any one of claims 11-14; or... The flexible pressure sensor includes a first substrate layer and a second substrate layer disposed opposite to each other. A plurality of force-sensitive electrodes are arranged at intervals along a first direction on the first substrate layer, and a plurality of conductive electrodes are arranged at intervals along a second direction on the second substrate layer. The first direction and the second direction are arranged at an angle. A portion of the plurality of force-sensitive electrodes overlaps with a portion of the plurality of conductive electrodes and is electrically connected. The force-sensitive electrode includes a conductor and a conductive layer. The conductive layer is laid on the conductor, and the resistance of the conductive layer changes with the external force applied.

16. An electronic device, characterized in that, The electronic device includes the force-sensitive electrode as described in claim 10; or... The electronic device includes the flexible pressure sensor as described in claim 15; or... The method for manufacturing the electronic device includes the method for manufacturing a force-sensitive electrode as described in any one of claims 1-9; or, The method of manufacturing the electronic device includes the method of manufacturing the flexible pressure sensor as described in any one of claims 11-14.

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