Tactile feedback device, touchpad and electronic equipment

Abstract

The invention discloses a tactile feedback device, a touchpad and electronic equipment. The tactile feedback device comprises a touchpad cover plate, at least one piezoelectric sensor, two force transmission structures, an elastic sheet structure, a piezoelectric wafer, a processing module and a base, the elastic sheet structure is arranged on the base; the touch panel cover plate is arranged on the elastic sheet structure and is connected with the tail end of the elastic sheet structure through the force transmission structure; the two force transmission structures are respectively arranged between the touch panel cover plate and the elastic sheet structure and are respectively arranged at the tail end of the elastic sheet structure, and the two force transmission structures and the elastic sheet structure form a cantilever beam; the piezoelectric sensor and the piezoelectric wafer are respectively arranged on different surfaces of the elastic sheet structure; when the touch panel cover plate is pressed, the cantilever beam is bent, and the piezoelectric sensor is stressed to generate a charge signal; and the processing module judges the charge signal, and sends an excitation electric signal to the piezoelectric wafer when judging that the charge signal is a pressing signal, so that the piezoelectric wafer stretches out and draws back in the horizontal direction to drive the cantilever beam to bend and generate vibration. Therefore, the tactile feedback device is sensitive to trigger, and excitation voltage is reduced.

Description

Tactile feedback device, touch panel and electronic device Technical Field

[0001] The present application relates to the field of tactile feedback technology, and in particular to a tactile feedback device, a touch panel, and an electronic device. Background Art

[0002] In some electronic devices, a touch panel (TP) is usually configured as an interactive input device for interacting with a user.

[0003] Currently, existing touchpads typically use two modules: mechanical buttons and capacitive touchpads. The capacitive touchpad module detects touch location, while the mechanical buttons produce a mouse-like click-like function and feel. Tactile feedback needs to simulate the feel of pressing and releasing physical buttons to give users a more realistic experience.

[0004] The tactile feedback solutions of existing touch panels generally use linear motor vibration feedback solutions or piezoelectric vibration feedback solutions. The linear motor vibration feedback solution is simple and convenient to drive, but it is expensive, large in size, and the modulation of the feel is more complex. Although the piezoelectric vibration solution has a better vibration effect, it requires high-voltage drive; and the piezoelectric sensor in the existing piezoelectric vibration solution can detect the touch panel's press signal, but it cannot detect slow presses or the defect of being difficult to trigger when slowly pressing; and it cannot detect the current pressure state of the piezoelectric sensor in real time. Once the press or lift signal is lost, it will give the user a feeling of no rebound after pressing, affecting the user experience.

[0005] Summary of the Invention

[0006] The embodiments of the present application aim to provide a tactile feedback device, a touchpad, and an electronic device, which can solve the problems that the tactile feedback solutions of existing touchpads are difficult to trigger when pressed slowly, and cannot produce a rebound feel after pressing, which affects the user experience, and are high in cost and complex to drive.

[0007] To solve the above technical problems, the first embodiment of the present application provides a tactile feedback device for use with a touch panel, comprising: a touch panel cover, at least one piezoelectric sensor, two force transmission structures, a spring structure, a piezoelectric chip, a processing module, and a base; wherein:

[0008] The spring structure is arranged on the base;

[0009] The touch panel cover is arranged on the spring structure, and the touch panel cover is connected to the end of the spring structure through the force transmission structure;

[0010] The two force transmission structures are respectively arranged between the touch panel cover and the spring structure, and are respectively arranged at the ends of the spring structure, forming a cantilever beam with the spring structure;

[0011] The piezoelectric sensor and the piezoelectric wafer are respectively arranged on different surfaces of the spring structure and close to the base;

[0012] When the touchpad cover is pressed, the cantilever beam bends. After receiving the pressing signal, the piezoelectric sensor is subjected to force to generate a charge signal, and the charge signal is sent to the processing module. The processing module judges the charge signal. When it is judged to be a pressing signal, the processing module sends an excitation electrical signal to the piezoelectric chip, so that the piezoelectric chip expands and contracts in the horizontal direction, driving the cantilever beam to bend and generate vibration.

[0013] In one embodiment, the two force transmission structures are respectively arranged at the ends of the spring structure, and form a cantilever beam with the spring structure; including: the two force transmission structures are respectively arranged at the two ends of the upper surface of the spring structure, and are symmetrically distributed along the two ends of the spring structure with the base as the midpoint, and the two force transmission structures and the spring structure form a cantilever beam.

[0014] In one embodiment, the tactile feedback device further includes a fixing component; the spring structure is fixedly mounted on the base via the fixing component.

[0015] In one embodiment, the piezoelectric sensor is fixed on the surface of the spring structure through the fixing assembly.

[0016] In one embodiment, the piezoelectric chip is fixed on the surface of the spring structure by the fixing component.

[0017] In one embodiment, the fixing component includes screws or glue.

[0018] In one embodiment, the touchpad cover includes a front surface of the touchpad cover, a back surface of the touchpad cover and a touch module, wherein the front surface of the touchpad cover is used for a user to touch and press; the touch module is arranged on the back surface of the touchpad cover and is electrically connected to the piezoelectric sensor and the piezoelectric chip respectively.

[0019] In one embodiment, a low-pass filter is provided at the detection signal end of the piezoelectric sensor, and the low-pass filter filters out the vibration waveform signal of the tactile feedback generated by the piezoelectric chip, leaving only the low-frequency pressing signal of the pressing waveform.

[0020] Correspondingly, the second embodiment of the present application provides a touch panel, which includes the tactile feedback device described in the first embodiment of the present application.

[0021] Correspondingly, an embodiment of the third aspect of the present application provides an electronic device, which includes the touch panel and a housing described in the embodiment of the second aspect of the present application, and the touch panel is fixedly arranged in the housing.

[0022] Compared with the prior art, the present application provides a tactile feedback device, a touchpad, and an electronic device. The tactile feedback device is applied to the touchpad and includes: a touchpad cover, at least one piezoelectric sensor, two force transmission structures, a spring structure, a piezoelectric chip, and a base. By fixing the spring structure on the base, the piezoelectric sensor and the piezoelectric chip are respectively arranged on different surfaces of the spring structure and close to the base, so that the piezoelectric chip and the piezoelectric sensor form a separate and independently arranged layout, so that the piezoelectric chip and the piezoelectric sensor can work independently, which can make slow pressing more sensitive and easy to trigger, and make the triggering more sensitive and stable. ; and the two force transmission structures are respectively arranged at the ends of the shrapnel structure, forming a cantilever beam with the shrapnel structure, so that the tactile feedback device can operate in the resonance range, the vibration amount is increased, and the excitation voltage is reduced (reduced to 42% of the excitation voltage of the piezoelectric sensing and excitation two-in-one solution), so that the tactile feedback device has low cost, simple debugging, light volume, sensitive triggering, and fast response, and the excitation voltage is reduced, the vibration amount is increased, and the user experience is improved, thereby solving the problem that the tactile feedback solution of the existing touch panel is difficult to trigger when pressed slowly, and there is no rebound feel after pressing, which affects the user experience, and the cost is high and the driving is complex. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0024] FIG1 is a first structural schematic diagram of a tactile feedback device provided by the present application;

[0025] FIG2 is a second structural diagram of a tactile feedback device provided by the present application;

[0026] FIG3 is a schematic diagram of a tactile feedback device provided by the present application showing a spring structure undergoing bending deformation;

[0027] FIG4 is a schematic structural diagram of an equivalent system of a tactile feedback device provided by the present application;

[0028] FIG5 is a schematic diagram of a tactile feedback device provided by the present application in a pressed state;

[0029] FIG6 is a circuit diagram of a tactile feedback device provided by the present application for performing signal conversion through a charge amplifier;

[0030] FIG7 is a schematic diagram of comparing the output voltages of a piezoelectric sensor in a tactile feedback device provided by the present application and an existing piezoelectric sensor;

[0031] FIG8 is a schematic diagram of voltage changes in a tactile feedback device provided by the present application when filtering a detection signal terminal of a piezoelectric sensor;

[0032] FIG9 is a schematic structural diagram of a touch panel provided by the present application;

[0033] FIG10 is a schematic structural diagram of an electronic device provided in this application.

[0034] Main component symbols: Tactile feedback device 1 Touch panel cover 11 Piezoelectric sensor 12 Force transmission structure 13 Spring structure 14 Piezoelectric chip 15 Base 16 Glue 171 Screw 172 Touch panel 10 Housing 20 Electronic device 100 DETAILED DESCRIPTION

[0035] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as being "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "upper", "lower", "inner", "outer", "bottom" and the like used in this specification indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0036] Unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" as used in this specification includes any and all combinations of one or more of the relevant listed items.

[0037] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0038] Currently, most existing touch panels use two modules: mechanical buttons and capacitive touch panels. The capacitive touch panel module detects the touch position, and the mechanical buttons produce a function and feel similar to a mouse click.

[0039] Tactile feedback needs to simulate the feel of pressing and lifting physical buttons to give users a more realistic experience. Most existing tactile feedback devices use linear motors or piezoelectric ceramic solutions. Linear motors are simple and convenient to drive, but they are expensive, large in size, and more complex to modulate the feel. The piezoelectric ceramic solution has a better vibration effect, but requires high-voltage drive. Existing piezoelectric tactile feedback devices generally include a piezoelectric sensor. Although the piezoelectric sensor can detect the pressing signal of the touch panel, it cannot detect the defect of slow pressing. In addition, existing tactile feedback devices generally adopt a two-in-one solution that combines the sensing mode and the excitation mode (a two-in-one design of a piezoelectric sensor and an exciter), but the two-in-one solution cannot maintain the output voltage of the sensing mode (as shown in the output voltage waveform of the existing tactile feedback device above in Figure 7). Judging from the output voltage waveform of the existing piezoelectric sensor above in Figure 7, the two-in-one solution can only measure the rising and falling edges of pressing and releasing and the positive and negative pulses generated. The drawback of this solution is that it can't detect the current pressure state of the piezoelectric sensor in real time. It can't detect slow presses, or it can be difficult to trigger when pressed slowly. If the press or release signal is lost, the user will feel like the touchscreen is unable to rebound after pressing. Furthermore, because it can only detect changes in the rising and falling edges, when the user slowly presses the touchpad, the rising and falling edges are not obvious, resulting in increased trigger force or even no trigger at all, which affects the user experience.

[0040] To this end, the inventors discovered the above technical problems during the research and development process and proposed a tactile feedback device, including: a touch panel cover, two piezoelectric sensors, two force transmission structures, a spring structure, a piezoelectric chip and a base; by fixing the spring structure on the base, the piezoelectric sensor and the piezoelectric chip are respectively arranged on different surfaces of the spring structure and close to the base, so that the piezoelectric chip and the piezoelectric sensor form a separate and independent arrangement, which can make the triggering more sensitive and stable; and the two force transmission structures are respectively arranged at the ends of the spring structure, forming a cantilever beam with the spring structure, The tactile feedback device can be made to operate in the resonance range, with a larger vibration amount, and the excitation voltage can be reduced (to 42% of the excitation voltage of the piezoelectric sensing and excitation two-in-one solution). A lower-cost driver chip can be used, so that the tactile feedback device has low cost, simple debugging, light volume, sensitive triggering, and fast response. The excitation voltage is reduced, the vibration amount is larger, and the user experience is improved. This can solve the problem that the tactile feedback solution of the existing touch panel is difficult to trigger when pressed slowly, and there is no rebound feel after pressing, which affects the user experience, and the cost is high and the driving is complex.

[0041] In order to facilitate understanding of the above inventive concepts of the present application, the above inventive concepts of the present application are described in more detail below with reference to the accompanying drawings and specific embodiments.

[0042] In one embodiment, as shown in FIG1 , the present application provides a tactile feedback device for use with a touch panel. The tactile feedback device 1 includes: a touch panel cover 11, at least one piezoelectric sensor 12, two force transmission structures 13, a spring structure 14, a piezoelectric chip 15, a processing module (not shown), and a base 16; wherein:

[0043] The spring structure 14 is fixedly mounted on the base 16;

[0044] The touch panel cover 11 is disposed on the spring structure 14 , and the touch panel cover 11 is connected to the end of the spring structure 14 via the force transmission structure 13 ;

[0045] The two force transmission structures 13 are respectively disposed between the touch panel cover 11 and the spring structure 14 and at the ends of the spring structure 14 to form a cantilever beam with the spring structure 14;

[0046] The piezoelectric sensor 12 and the piezoelectric chip 15 are respectively arranged on different surfaces of the spring structure 14 and close to the base 16. It is worth noting that when the inventor set the positions of the piezoelectric sensor 12 and the piezoelectric chip 15, the industry's common practice is to set the piezoelectric sensor 12 at the bottom of the touch panel or at the two ends of the spring structure. However, after testing, the sensor signals at the above positions have some blind spots for pressing at certain positions and signal confusion. During the research and development process, the applicant continuously explored and tested and optimized, and found that the press signal recognition is best when the piezoelectric sensor 12 is set on the surface of the spring structure 14 and close to the base 16. In addition, for the piezoelectric chip, the industry's common practice is to set the piezoelectric chip at the two ends of the spring structure. However, after testing, it was found that if the piezoelectric chip is set at the two ends of the spring structure, the vibration distribution of the entire touch panel will be uneven and the vibration amplitude will become smaller. During the research and development process, the applicant continuously explored and tested and optimized, and found that the vibration is evenly distributed and the vibration amplitude can be improved when the piezoelectric sensor is set on the surface of the spring structure and close to the base.

[0047] When the touch panel cover 11 is pressed, the cantilever beam bends. After receiving the pressing signal, the piezoelectric sensor 12 is subjected to force to generate a charge signal, and the charge signal is sent to the processing module. The processing module judges the charge signal. When it is judged to be a pressing signal, the processing module sends an excitation electrical signal to the piezoelectric chip 15, so that the piezoelectric chip 15 expands and contracts in the horizontal direction, driving the cantilever beam to bend and generate vibration.

[0048] In this embodiment, the spring structure is fixedly mounted on the base, and the piezoelectric sensor and the piezoelectric chip are respectively positioned on different surfaces of the spring structure and close to the base. This allows the piezoelectric chip and the piezoelectric sensor to form a separate, independently arranged layout, allowing the piezoelectric chip and the piezoelectric sensor to operate independently. This makes slow pressing more sensitive and easier to trigger, and the triggering more sensitive and stable. In addition, the two force transmission structures are respectively positioned at the ends of the spring structure, forming a cantilever beam with the spring structure. This allows the tactile feedback device to operate in the resonance range, increasing the vibration amount and reducing the excitation voltage (to 42% of the excitation voltage of the piezoelectric sensing and excitation two-in-one solution). This allows the use of a lower-cost driver chip, resulting in a low-cost, simple to debug, lightweight, sensitive to triggering, and fast response. Furthermore, the reduced excitation voltage increases the vibration amount, improving the user experience. This solves the problems of existing touchpad tactile feedback solutions that are difficult to trigger when slowly pressing, lack a rebound feel after pressing, which affects the user experience, are high in cost, and are complex to drive.

[0049] In one embodiment, the tactile feedback device 1 further includes a fixing assembly. The spring structure 14 is fixedly disposed on the base 16. Specifically, the spring structure 14 is fixedly mounted on the base 16 via the fixing assembly.

[0050] For example, as shown in FIG1 , the fixing component is a screw 172 , and the spring structure 14 is fixedly mounted on the base 16 by the screw 172 , so that the spring structure 14 can be more firmly mounted on the base 16 by screw locking, and is more convenient to assemble and disassemble.

[0051] For another example, as shown in FIG2 , the fixing component is glue 171 , and the spring structure 14 is fixedly mounted on the base 16 by the glue 171 , so that the spring structure 14 can be more firmly mounted on the base 16 by gluing.

[0052] In one embodiment, as shown in Figures 1 and 2, the touchpad cover 11 is arranged on the spring structure 14, and the touchpad cover 11 is connected to the end of the spring structure 14 through the force transmission structure 13; the two force transmission structures 13 are respectively arranged between the touchpad cover 11 and the spring structure 14, and are respectively arranged at the end of the spring structure 14, forming a cantilever beam with the spring structure 14.

[0053] Specifically, as shown in Figures 1 and 2, two force transmission structures 13 are respectively disposed at the two ends of the upper surface of the spring structure 14, and are symmetrically distributed along the two ends of the spring structure 14 with the base 16 as the midpoint. The two force transmission structures 13 and the spring structure 14 form a cantilever beam disposed on the base 16, and the touchpad cover 11 is disposed above the two force transmission structures 13.

[0054] For example, the force transmission structure 13 is a silicone pad, and the spring structure 14 is a metal spring.

[0055] In one embodiment, the piezoelectric sensor 12 and the piezoelectric wafer 15 are respectively disposed on different surfaces of the spring structure 14 to avoid mutual interference between sensing and actuation, and are located close to the base 16 .

[0056] For example, as shown in Figures 1 and 2, the piezoelectric sensor 12 is arranged on the upper surface of the spring structure 14 and close to the base 16, and the piezoelectric chip 15 is arranged on the lower surface of the spring structure 14 and close to the base 16, so that the piezoelectric chip 15 and the piezoelectric sensor 12 form a separate and independently arranged layout, so that the piezoelectric chip 15 and the piezoelectric sensor 12 can work independently, making slow pressing more sensitive and easy to trigger, and making the triggering more sensitive and stable. In the subsequent embodiments, the piezoelectric sensor 12 is arranged on the upper surface of the spring structure 14 and close to the base 16, and the piezoelectric chip 15 is arranged on the lower surface of the spring structure 14 and close to the base 16 as an example for detailed description.

[0057] For another example, the piezoelectric sensor 12 is arranged on the lower surface of the spring structure 14 and close to the base 16, and the piezoelectric chip 15 is arranged on the upper surface of the spring structure 14 and close to the base 16, so that the piezoelectric chip 15 and the piezoelectric sensor 12 form a separate and individually arranged layout, so that the piezoelectric chip 15 and the piezoelectric sensor 12 can work independently, which can make slow pressing more sensitive and easy to trigger, and make the triggering more sensitive and stable.

[0058] Furthermore, the piezoelectric sensor 12 and the piezoelectric chip 15 can be respectively mounted on different surfaces of the spring structure 14 by screwing, or by gluing. For specific implementations, reference can be made to the screwing and gluing methods used to secure the spring structure to the base 16, which will not be described in detail here.

[0059] Furthermore, the piezoelectric chip 15 is a piezoelectric single chip, which is disposed on the upper surface of the spring structure 14 and close to the base 16 or on the lower surface of the spring structure 14 and close to the base 16 .

[0060] Specifically, the piezoelectric unimorph includes a single layer of piezoelectric ceramics to reduce an excitation voltage.

[0061] The piezoelectric single crystal may also include multilayer piezoelectric ceramics to further reduce the excitation voltage.

[0062] Furthermore, the piezoelectric sensor 12 is used to generate a charge signal when the touch panel cover 11 is pressed to bend the cantilever beam, and the charge signal generated by the force is collected by the processing module and determined as a pressing signal.

[0063] The sensing mode includes: when the touch panel cover 11 is pressed by applying a pressing force, the pressing force bends the spring structure constituting the cantilever beam through the force transmission structure, and the piezoelectric sensor 12 is thus subjected to a force to generate a charge signal, which is collected by the processing module and determined as a pressing signal.

[0064] The piezoelectric chip 15 is used as an actuator. After the pressing signal is determined, the piezoelectric chip 15 is used to expand and contract in the horizontal direction after the processing module applies an excitation electrical signal, thereby driving the cantilever beam to bend and generate tactile feedback. In other words, the piezoelectric chip 15 is used in the excitation mode.

[0065] The excitation mode includes: after determining the pressing signal, the processing module emits an excitation electrical signal and applies it to the piezoelectric chip 15. After the processing module applies the excitation electrical signal, the piezoelectric chip 15 expands and contracts in the horizontal direction, causing the spring structure 14 to bend and deform, thereby causing the end of the spring structure 14 to displace. The spring structure 14 pushes the touch panel cover 11 to displace, generating tactile feedback.

[0066] For example, as shown in Figures 1 and 2 , the piezoelectric sensor 12 is disposed on the upper surface of the spring structure 14, near the base 16, and the piezoelectric chip 15 is disposed on the lower surface of the spring structure 14, near the base 16. When the touchpad cover 11 is pressed, the cantilever beam bends (ie, the spring structure that constitutes the cantilever beam bends). The piezoelectric sensor 12 is subjected to the force and generates a charge signal, which is collected by the processing module and determined as a press signal. After determining the press signal, the piezoelectric chip 15, after being applied with an excitation electrical signal by the processing module, extends or contracts horizontally (as indicated by the arrows in Figures 1 and 2 ), causing the spring structure 14 that constitutes the cantilever beam to bend and deform, causing the end of the spring structure to displace (as shown in Figure 3 ). The end of the spring structure 14 produces the largest displacement. When the touchpad cover 11 is connected to the end of the spring structure 14, the spring structure 14 pushes the touchpad cover 11 to also produce a larger displacement, thereby generating tactile feedback.

[0067] Furthermore, the principle by which the cantilever beam structure composed of the spring structure 14 and the two force transmission structures 13 can generate vibrations is the direct piezoelectric effect.

[0068] Specifically, the principle by which the tactile feedback device 1 of the present application can generate vibrations can be described by an equivalent system as shown in FIG. 4 .

[0069] The equivalent system includes: the lateral expansion and contraction force generated by the piezoelectric chip 15 , the equivalent stiffness coefficient k of the spring structure 14 , the equivalent mass m of the touch panel cover 11 , and the damping C of the force transmission structure 13 .

[0070] The resonance frequency f of the equivalent system is controlled by the above parameters. The resonance frequency is calculated as follows: f=1 / 2π*sqrt(K / m).

[0071] In order to maximize the output vibration, the displacement is maximum when the frequency of the input signal coincides with the resonant frequency of the equivalent system.

[0072] In this embodiment, the touchpad cover 11 is arranged on the spring structure 14, and the touchpad cover 11 is connected to the end of the spring structure 14 through the force transmission structure 13; the two force transmission structures 13 are respectively arranged between the touchpad cover 11 and the spring structure 14, and are respectively arranged at the ends of the spring structure 14, forming a cantilever beam with the spring structure 14, so that the tactile feedback device can operate in the resonance range, the vibration amount is increased, and the excitation voltage is reduced (reduced to 42% of the excitation voltage of the piezoelectric sensing and excitation two-in-one solution); the piezoelectric sensor 12 and the piezoelectric chip 15 are respectively arranged on different surfaces of the spring structure 14 and close to the base 16, so that the piezoelectric chip 15 and the piezoelectric sensor 12 can form a separate and separately arranged layout, so that the piezoelectric chip 15 and the piezoelectric sensor 12 can work independently, which can make slow pressing more sensitive and easy to trigger, and make the triggering more sensitive and stable.

[0073] In one embodiment, the piezoelectric sensor 12 is arranged on the surface of the shrapnel structure 14 and close to the base 16. For example, the piezoelectric sensor 12 is arranged on the upper surface of the shrapnel structure 14 and close to the base 16. Alternatively, the piezoelectric sensor 12 is arranged on the lower surface of the shrapnel structure 14 and close to the base 16.

[0074] In the present application, the touchpad cover 11 includes a front surface, a back surface, and a touch module. The front surface is used for a user to touch and press. The touch module is provided on the back surface of the touchpad cover and is electrically connected to the piezoelectric sensor 12 and the piezoelectric chip 15, respectively. The processing module can be provided in the touch module. The processing module is used to collect the charge signal of the piezoelectric sensor 12 and determine it as a press signal. After determining the press signal, the processing module transmits an excitation electrical signal to the piezoelectric chip 15.

[0075] It is understood that the processing module is an integrated circuit chip with signal processing capabilities. For example, the processing module can be a general-purpose processor, a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc.; the general-purpose processor can be a microprocessor, an MCU (Microcontroller Unit), or any conventional processor, etc.

[0076] At least one piezoelectric sensor 12 is provided on the surface of the spring structure 14. The piezoelectric sensor 12 is electrically connected to the touch module and is used in a sensing mode. When the touch panel cover 11 is pressed to bend the cantilever beam, the charge signal generated by the force is collected by the processing module and determined as a pressing signal.

[0077] As shown in Figure 5, when the touchpad cover 11 is pressed, due to the presence of the action force and the reaction force of the spring structure 14, the piezoelectric sensor 12 will be compressed to generate a charge signal. The generated charge signal is converted into a voltage signal VOUT by the charge amplifier 200 shown in Figure 6 and amplified and collected by the processing module, thereby generating a pressing signal. Compared with the voltage amplifier, the charge amplifier used in this application is easier to retain low-frequency components and is not easily affected by cable capacitance. The low-frequency component of the pressing waveform generated when the touchpad cover 11 is pressed is generally within 10Hz and will not exceed 100Hz.

[0078] The piezoelectric sensor of the existing touchpad tactile feedback solution can detect the touchpad's pressing signal, but it cannot detect the defect of slow pressing. In addition, the existing touchpad tactile feedback solution generally adopts a two-in-one solution that combines the sensing mode and the excitation mode, but the two-in-one solution cannot maintain the output voltage of the sensing mode (as shown in the output voltage waveform of the existing piezoelectric sensor above Figure 7). From the output voltage waveform of the existing piezoelectric sensor above Figure 7, the two-in-one solution can only measure the rising and falling edges of pressing and releasing and the positive and negative pulses generated. The defect of this solution is that it cannot detect the current pressure state of the piezoelectric sensor in real time. Once the pressing or lifting signal is lost, the user will feel that the hand cannot rebound after pressing. In addition, since only the changes in the rising and falling edges can be detected, when the user slowly presses the touchpad, the rising and falling edges are not obvious, and the trigger force will increase or the trigger will not be triggered, thereby affecting the user experience.

[0079] In the tactile feedback device 1 of the present application, the piezoelectric sensor 12 and the piezoelectric chip 15 are respectively arranged on different surfaces of the spring structure 14 and close to the base 16. The piezoelectric sensor 12 and the piezoelectric chip 15 are respectively electrically connected to the touch module arranged on the back of the touch panel cover, so that the piezoelectric chip 15 and the piezoelectric sensor 12 form a separate and independent arrangement layout, which can make the triggering more sensitive and stable, and can make the piezoelectric sensor 12 maintain the output voltage in the sensing mode (as shown in the output voltage waveform of the piezoelectric sensor in the tactile feedback device of the present application in the lower part of Figure 7). From the output voltage waveform of the piezoelectric sensor in the tactile feedback device of the present application shown in the lower part of Figure 7, it can be seen that the separate and independent arrangement layout of the piezoelectric chip and the piezoelectric sensor of the present application detects the rising and falling edges of pressing and releasing and generates positive and negative pulses, and can maintain the output voltage in the pressed state, so that the current pressure state of the piezoelectric sensor can be detected in real time. Even if the pressing or lifting signal is lost, it will give the user a feeling of rebound after pressing. In addition, since the output voltage state can be maintained, when the user slowly presses the touchpad, the rising and falling edges are more obvious, and the trigger force does not increase or the trigger cannot be triggered, thereby improving the user experience. Since the piezoelectric sensor 12 is a low-voltage circuit, it will not affect the capacitive touch of the touchpad cover 11. Compared with the setting method of existing piezoelectric sensors, the above-mentioned setting method of the piezoelectric sensor 12 inherits the low-cost feature of piezoelectric sensors for force detection and overcomes the defect that piezoelectric sensors cannot detect slow presses.

[0080] As shown in Figure 8, in addition to detecting the pressing signal (i.e., charge signal) during operation, the piezoelectric sensor 12 also detects the vibration waveform signal of the tactile feedback generated by the piezoelectric chip 15. However, the vibration waveform of the tactile feedback is generally a pulse signal with a center frequency of 150-250Hz, while the pressing waveform is a low-frequency signal within 10Hz. Therefore, a low-pass filter is set at the detection signal end of the piezoelectric sensor 12. The low-pass filter can filter out the vibration waveform signal of the tactile feedback generated by the piezoelectric chip 15, leaving only the low-frequency pressing signal of the pressing waveform, and send the low-frequency pressing signal (i.e., charge signal) to the processing module.

[0081] In this embodiment, the touchpad cover 11 is arranged on the spring structure 14, and the touchpad cover 11 is connected to the end of the spring structure 14 through the force transmission structure 13; the two force transmission structures 13 are respectively arranged between the touchpad cover 11 and the spring structure 14, and are respectively arranged at the ends of the spring structure 14, forming a cantilever beam with the spring structure 14; the piezoelectric sensor 12 and the piezoelectric chip 15 are respectively arranged on different surfaces of the spring structure 14, so that the tactile feedback device combines the advantages of the existing linear motor vibration feedback solution and the piezoelectric vibration feedback solution, and also partially improves the defects of the existing piezoelectric vibration feedback solution, such as: insufficient vibration when the excitation voltage is low, insufficient energy conversion efficiency of the actuator, and difficulty in triggering when slowly pressing when the piezoelectric sensor and actuator are two-in-one. In addition, the tactile feedback device operates in the resonance range, which can reduce the excitation voltage (to 42% of the excitation voltage of the piezoelectric sensing and excitation two-in-one solution), and the piezoelectric chip and the piezoelectric sensor are separated and separately arranged to make the triggering more sensitive and stable.

[0082] Based on the same concept, as shown in FIG9 , the present application further provides a touch panel. The touch panel 10 includes the tactile feedback device 1 described in any one of the above embodiments.

[0083] In this embodiment, the tactile feedback device 1 is consistent with the tactile feedback device 1 described in any of the above embodiments. For specific structures and functions, reference may be made to the tactile feedback device 1 described in any of the above embodiments, and details will not be repeated here.

[0084] In this embodiment, a touch panel is provided, including a tactile feedback device. The tactile feedback device comprises a spring structure fixedly mounted on a base, and a piezoelectric sensor and a piezoelectric chip respectively disposed on different surfaces of the spring structure and proximate to the base. This allows the piezoelectric chip and the piezoelectric sensor to form a separate, independently arranged layout, enabling the piezoelectric chip and the piezoelectric sensor to operate independently. This makes slow pressing more sensitive and easier to trigger, and the triggering more sensitive and stable. Furthermore, two force transmission structures are disposed at the ends of the spring structure, forming a cantilever beam with the spring structure. This allows the tactile feedback device to operate in a resonant range, increasing the vibration amplitude and reducing the excitation voltage (to 42% of the excitation voltage of a two-in-one piezoelectric sensing and excitation solution). This results in a low-cost, simple to debug, lightweight, sensitive triggering, and fast response. Furthermore, the reduced excitation voltage increases the vibration amplitude, improving the user experience. This solves the problems with existing touch panel tactile feedback solutions, such as difficulty in triggering when pressing slowly, a lack of rebound after pressing, which affects the user experience, high cost, and complex operation.

[0085] It should be noted that the above-mentioned touch panel embodiment and the above-mentioned tactile feedback device embodiment belong to the same concept. The specific implementation process is detailed in the tactile feedback device embodiment, and the technical features in the tactile feedback device embodiment are correspondingly applicable in the above-mentioned touch panel embodiment, which will not be repeated here.

[0086] Based on the same concept, as shown in FIG10 , the present application further provides an electronic device. The electronic device 100 includes the touch panel 10 and a housing 20 as described in any of the above embodiments. The touch panel 10 is fixedly disposed in the housing 20 .

[0087] In this embodiment, the touch panel 10 is consistent with the touch panel 10 described in any of the above embodiments. The specific structure and function can refer to the touch panel 10 described in any of the above embodiments, and will not be repeated here.

[0088] In this embodiment, an electronic device is provided, including a touch panel and a housing, wherein the touch panel is fixedly disposed in the housing. The touchpad includes a tactile feedback device. The tactile feedback device securely mounts a spring structure on a base, with a piezoelectric sensor and a piezoelectric chip disposed on different surfaces of the spring structure and proximate to the base. This allows the piezoelectric chip and the piezoelectric sensor to form a separate, independently arranged layout, enabling the piezoelectric chip and the piezoelectric sensor to operate independently. This makes slow pressing more sensitive and easier to trigger, and the triggering more sensitive and stable. Furthermore, two force transmission structures are disposed at the ends of the spring structure, forming a cantilever beam with the spring structure. This allows the tactile feedback device to operate in a resonant range, increasing the vibration and increasing the excitation voltage (reduced to 42% of the excitation voltage of a two-in-one piezoelectric sensing and excitation solution). This results in a low-cost, simple-to-debug, lightweight, sensitive triggering, and fast response haptic feedback device. Furthermore, by reducing the excitation voltage and increasing the vibration, the user experience is enhanced. This solves the problems with existing touchpad tactile feedback solutions, such as difficulty in triggering when pressing slowly and the lack of a rebound feeling after pressing, which affects the user experience, as well as high cost and complex operation.

[0089] It should be noted that the above-mentioned electronic device embodiment and the above-mentioned touch panel embodiment belong to the same concept. The specific implementation process is detailed in the touch panel embodiment, and the technical features in the touch panel embodiment are applicable to the above-mentioned electronic device embodiment, which will not be repeated here.

[0090] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0091] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Based on the idea of ​​the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present application as described above. For the sake of simplicity, they are not provided in detail. Although the present application has been described in detail with reference to the above embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A tactile feedback device, characterized in that, Applied to a touchpad, including: a touchpad cover plate, at least one piezoelectric sensor, two force transmission structures, a shrapnel structure, a piezoelectric wafer, a processing module, and a base; wherein: The shrapnel structure is arranged on the base; The touchpad cover plate is arranged on the shrapnel structure, and the touchpad cover plate is connected to the end of the shrapnel structure through the force transmission structure; The two force transmission structures are respectively arranged between the touchpad cover plate and the shrapnel structure, and are respectively arranged at the end of the shrapnel structure, and form a cantilever beam with the shrapnel structure; The piezoelectric sensor and the piezoelectric wafer are respectively arranged on different surfaces of the shrapnel structure and close to the position of the base; When the touchpad cover plate is pressed, the cantilever beam bends. After the piezoelectric sensor receives the pressing signal, it generates a charge signal under force and sends the charge signal to the processing module; the processing module judges the charge signal. When it is judged as a pressing signal, the processing module sends an excitation electrical signal to the piezoelectric wafer to make the piezoelectric wafer expand and contract in the horizontal direction, driving the cantilever beam to bend and generate vibration.

2. The tactile feedback device according to claim 1, wherein The two force transmission structures are respectively arranged at the ends of the shrapnel structure and form a cantilever beam with the shrapnel structure; including: The two force transmission structures are respectively arranged at the two ends of the upper surface of the shrapnel structure, and are symmetrically distributed along the two ends of the shrapnel structure with the base as the midpoint. The two force transmission structures and the shrapnel structure form a cantilever beam.

3. The tactile feedback device according to claim 1, wherein The haptic feedback device further includes a fixing component; the shrapnel structure is fixedly installed on the base through the fixing component.

4. The haptic feedback device according to claim 3, wherein The piezoelectric sensor is fixedly arranged on the surface of the shrapnel structure through the fixing component.

5. The tactile feedback device according to claim 3, characterized in that, The piezoelectric wafer is fixedly arranged on the surface of the shrapnel structure through the fixing component.

6. The tactile feedback device according to claim 3, wherein The fixing component includes screws or glue.

7. The haptic feedback device according to claim 1, wherein, The touchpad cover plate includes a front surface of the touchpad cover plate, a back surface of the touchpad cover plate, and a touch module. The front surface of the touchpad cover plate is used for the user to perform touch pressing; the touch module is arranged on the back surface of the touchpad cover plate and is electrically connected to the piezoelectric sensor and the piezoelectric wafer respectively.

8. The tactile feedback device according to claim 1, wherein A low-pass filter is arranged at the detection signal end of the piezoelectric sensor. The low-pass filter filters out the vibration waveform signal of the haptic feedback generated by the piezoelectric wafer and only leaves the low-frequency pressing signal of the pressing waveform.

9. A touchpad, characterized in that, The touchpad includes the haptic feedback device according to any one of claims 1 to 8.

10. An electronic device, characterized in that, The electronic device includes the touchpad according to claim 9 and a housing, and the touchpad is fixedly arranged in the housing.

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