Piezoelectric ceramic tactile feedback amplification structure

Abstract

The utility model relates to the technical field of tactile feedback, especially relates to a piezoelectric ceramic tactile feedback amplification structure, include: ceramic subassembly, including multilayer ceramic sheet, two ceramic sheet electrodes positive and negative opposite and intercommunication, ceramic sheet outside is provided with outer electrode, conductive subassembly, including with the fixed part of parallel setting and connection of ceramic subassembly surface, set up in the vibration part of the center position of conductive subassembly, with the fixed part between the transmission part of connection in the vibration part, the included angle is formed between transmission part and fixed part, and the included angle range is 1 to 10. The utility model cooperates with the ceramic subassembly and the transmission subassembly of multilayer ceramic sheet composition, control the range of the included angle between transmission part and fixed part, reduced the geometric stress concentration effect of fixed part and transmission part junction, make stress distribution from the form of local concentration change into more uniform state, effectively reduced the probability of stress concentration point fatigue crack, effectively balanced the relationship between performance, life and energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of tactile feedback technology, and in particular to a piezoelectric ceramic tactile feedback amplification structure. Background Technology

[0002] Haptic feedback technology plays a crucial role in modern human-computer interaction, evolving from simple notification vibrations to simulate complex and realistic physical tactile sensations. It is widely used in high-end smartphones, automotive infotainment systems, virtual reality controllers, and precision touchpads. Users expect to experience the click-like feel of mechanical buttons, the tactile feedback of scrolling wheels, and the friction of different surface materials. Piezoelectric ceramic materials are considered ideal driving sources due to their rapid response, low power consumption, and high control precision. However, because the deformation displacement of piezoelectric ceramic materials is too small to be directly perceived by the human fingertips, deformation amplification is achieved through coupling with a metal vibrating plate to realize effective displacement and force output.

[0003] In the prior art, such as the invention patent application CN112368670A filed on January 28, 2019, an electronic device is disclosed, having an operating element and a component for generating tactile signals. The component has a piezoelectric actuator, wherein the component is arranged below the operating element and is designed to generate vibration at the operating element. However, the inventors found in actual use that the vibration structure in the above-mentioned technical solution is prone to stress concentration in areas of abrupt geometric changes, leading to early fatigue failure. The stress concentration point becomes the source of fatigue crack initiation, which gradually expands under cyclic loading, eventually causing structural fracture and resulting in tactile function failure. It is difficult to balance performance, lifespan, and driving energy consumption of the vibrating pad. To enhance the tactile sensation, a larger displacement amplitude is required, but this requirement increases internal stress and accelerates the fatigue process. Increasing the thickness to reduce stress increases driving energy consumption and reduces the tactile quality.

[0004] Therefore, a design solution is urgently needed to solve the above-mentioned technical problems, optimize the stress distribution inside the vibrator, reduce or eliminate stress concentration effects, and improve mechanical fatigue life. Utility Model Content

[0005] In view of at least one of the above technical problems, the present invention provides a piezoelectric ceramic tactile feedback amplification structure, which improves the mechanical fatigue life by improving the internal structure of the vibrating plate.

[0006] According to a first aspect of the present invention, a piezoelectric ceramic tactile feedback amplification structure is provided, comprising: A ceramic component includes multiple ceramic sheets, wherein the electrodes of two adjacent ceramic sheets are opposite in polarity and interconnected, and an external electrode is provided on the outside of each ceramic sheet; The conductive component includes a fixed part that is parallel to and connected to the surface of the ceramic component, a vibrating part disposed at the center of the conductive component, and a conductive part that connects the vibrating part and the fixed part. The conductive part and the fixed part form an angle between them, the angle ranging from 1° to 10°.

[0007] In some embodiments of this utility model, the ceramic sheet has an internal electrode structure, and two adjacent ceramic sheets are riveted together or fixedly connected at the side ends.

[0008] In some embodiments of this utility model, the external electrodes are disposed on both sides of the ceramic sheet, or on the upper and lower surfaces of the ceramic sheet, and the external electrodes are in communication with the internal electrodes.

[0009] In some embodiments of this utility model, the thickness of a single ceramic sheet ranges from 15 mm. Up to 100 .

[0010] In some embodiments of this utility model, an adhesive is provided between the fixing part and the ceramic component, and a groove is provided on the side of the fixing part that is bonded to the ceramic component.

[0011] In some embodiments of this utility model, the conductive part is shaped like a spherical crown, and at least one stress relief groove is provided on the conductive part. The stress relief groove is located between the fixed part and the vibrating part, and the stress relief groove has a widening structure, with the width near the fixed part being greater than the width near the vibrating part.

[0012] In some embodiments of this utility model, the cross-section of the conductive part perpendicular to the fixing part is a wave-shaped structure, and the wave-shaped structure includes at least one set of first broken line segments and second broken line segments.

[0013] In some embodiments of this utility model, the first broken line segment forms a first angle with the fixing part ranging from 15° to 30°, and the second broken line segment forms a second angle with the fixing part ranging from 5° to 15°, wherein the first angle is greater than the second angle.

[0014] In some embodiments of this utility model, the ratio of the projection length of the first broken line on the plane where the fixed part is located to the projection length of the second broken line on the plane where the fixed part is located is 1:2 to 1:3.

[0015] In some embodiments of this utility model, the conductive part is shaped like an elliptical crown.

[0016] The beneficial effects of this invention are as follows: This invention improves the mechanical properties of the vibrating plate by synergistically combining a ceramic component composed of multiple ceramic sheets with a conductive component. The conductive component includes a fixed part arranged parallel to the surface of the ceramic component, a vibrating part located at the center of the vibrating plate, and a conductive part connecting the two. The included angle between the conductive part and the fixed part is strictly limited to the range of 1° to 10°. Through structural optimization, compared with traditional solutions, the geometric stress concentration effect at the connection between the fixed part and the conductive part is reduced, transforming the stress distribution from a localized concentration to a more uniform state, effectively reducing the probability of fatigue cracks at stress concentration points. The range of the included angle ensures the mechanical stability of the structure and provides the vibrating part with good displacement output capability, thereby maintaining low system energy consumption while enhancing tactile feedback performance. The gradual included angle effectively balances the relationship between performance, lifespan, and energy consumption, eliminating the need to rely on increasing thickness to achieve a high-strength structure, and making the drive process more precise and controllable, not only enhancing displacement amplification capability but also extending mechanical fatigue life. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the piezoelectric ceramic tactile feedback amplification structure in an embodiment of this utility model; Figure 2 This is a top view of the piezoelectric ceramic tactile feedback magnification structure in an embodiment of this utility model; Figure 3 This is a cross-sectional view of one embodiment of the conduction component in the piezoelectric ceramic tactile feedback amplification structure of this utility model.

[0019] Reference numerals: 1. Ceramic component; 11. Ceramic sheet; 2. Conducting component; 21. Fixing part; 22. Vibrating part; 23. Conducting part; 23a. Stress relief groove; 23b. First broken line segment; 23c. Second broken line segment. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0023] like Figures 1 to 3 The piezoelectric ceramic tactile feedback amplification structure shown includes: Ceramic component 1 includes multiple layers of ceramic sheets 11, with adjacent ceramic sheets 11 having opposite polarities and being interconnected. External electrodes are disposed on the exterior of each ceramic sheet 11. For example... Figure 1 As shown, it should be noted that the number of ceramic sheets 11 can range from 3 to 100 layers, depending on the specific requirements. Similarly, the electrodes between adjacent ceramic sheets 11 can be connected through metallized through-holes or by side welding. The external electrode can be coated on the outside of the ceramic sheet 11 and connected to the internal electrodes of the ceramic sheet 11.

[0024] The conductive component 2 includes a fixing part 21 that is parallel to and connected to the surface of the ceramic component 1, a vibrating part 22 disposed at the center of the conductive component 2, and a conductive part 23 connected between the vibrating part 22 and the fixing part 21. An angle is formed between the conductive part 23 and the fixing part 21, with the angle ranging from 1° to 10°. Figure 1As shown, it should be noted that the shape of the conductive part 23 can be varied, including a spherical crown, an elliptical crown, a wave-like shape, or other shapes that meet the included angle range. It should also be noted that the material of the conductive part 23 can be stainless steel, titanium alloy, or other conductive materials. The fixing part 21 is used to bond with the piezoelectric ceramic, forming the energy input interface; the vibrating part 22 is the energy output interface with the external device, used to transmit the amplified vibration to the user; the conductive part 23 connects the fixing part 21 and the vibrating part 22, used to mechanically amplify the micro-deformation of the ceramic component 1 and transmit it to the vibrating part 22. The connection between the conductive part 23 and the external device or external base can be achieved using double-sided adhesive or welding. The included angle between the conductive part 23 and the fixing part 21 ranges from 1° to 10°, ensuring structural mechanical strength and enabling a wide range of tactile force adjustment from weak to strong.

[0025] This invention improves the mechanical properties of a vibrating plate by synergistically combining a ceramic component 1 (composed of multiple ceramic sheets 11) and a transmission component 2. The transmission component 2 includes a fixing part 21 parallel to the surface of the ceramic component 1, a vibrating part 22 located at the center of the vibrating plate, and a transmission part 23 connecting the two. The angle between the transmission part 23 and the fixing part 21 is strictly limited to the range of 1° to 10°. Through structural optimization, compared with traditional solutions, the geometric stress concentration effect at the connection between the fixing part 21 and the transmission part 23 is reduced, transforming the stress distribution from a locally concentrated form to a more uniform state, effectively reducing the probability of fatigue cracks at stress concentration points. The range of the angle ensures the mechanical stability of the structure and provides the vibrating part 22 with good displacement output capability, thereby maintaining low system energy consumption while enhancing tactile feedback performance. The gradually changing angle effectively balances the relationship between performance, lifespan, and energy consumption, eliminating the need to rely on increasing thickness to achieve a high-strength structure, and providing more precise control during the driving process. This not only enhances displacement amplification capability but also extends mechanical fatigue life.

[0026] In some embodiments of this invention, the ceramic sheet 11 has an internal electrode structure, with two adjacent ceramic sheets 11 connected by riveting through openings or by fixed connection at the side ends. The internal electrode located inside the ceramic sheet 11 ensures more efficient electrode conduction while reducing the complexity of external electrode connections, thereby reducing manufacturing steps and improving system control accuracy. The riveting method, where openings are made between the ceramic sheets 11, utilizes riveting technology to achieve a firm connection between them, thus avoiding delamination and improving the overall mechanical strength of the assembly. Fixed connection at both ends of the side of the ceramic sheet 11 solves the shortcomings of traditional stacking connections, reduces stress concentration at the edges of the ceramic sheet 11, and significantly improves its lifespan.

[0027] To make the overall circuit conductivity more stable, in some embodiments of this utility model, such as Figure 1 As shown, the external electrodes are disposed on both sides of the ceramic sheet 11, or on the upper and lower surfaces of the ceramic sheet 11, and are electrically connected to the internal electrodes. The external electrodes can be selectively disposed on both sides of the ceramic sheet 11, or on the upper and lower surfaces of the ceramic sheet 11, while simultaneously being connected to the internal electrodes. The external electrodes are arranged across the entire surface of the ceramic sheet 11, closely cooperating with the internal electrodes to form a more stable electrical connection. The flexibility of various external electrode arrangements greatly enhances the adaptability of the structural design, meeting the spatial layout and design requirements of different application scenarios. Compared with traditional single-sided or partially covered electrode solutions, the external electrode layout of this invention enhances the adhesion between the electrodes and the ceramic sheet 11, reduces the risk of delamination during high-frequency vibration, and improves the conversion efficiency of electrical energy to mechanical energy, providing a more efficient and reliable driving source for the tactile feedback structure.

[0028] The thickness of the ceramic sheet 11 directly affects the vibration characteristics, deflection displacement amplitude, and energy conversion efficiency of the piezoelectric material, and is also related to the driving voltage and the mechanical strength density of the overall structure. In some embodiments of this invention, the thickness of a single ceramic sheet 11 ranges from 15 mm. Up to 100 The lower limit of the ceramic sheet 11 thickness ensures a high amplitude effect while reducing the driving voltage, enabling the system to operate efficiently with lower power consumption. The upper limit of the thickness ensures that the ceramic sheet 11 has sufficient mechanical strength to withstand frequent vibrations and external forces under high cyclic loads, avoiding the risk of fracture due to elastic fatigue or stress concentration. Through reasonable control of this range, the ceramic sheet 11 can achieve high-amplitude deformation to improve the realism of tactile feedback, while avoiding the mechanical fragility and manufacturing difficulties caused by excessive thinning. It can also be adapted to multi-layer ceramic stacked structures, further improving overall driving performance and energy conversion efficiency.

[0029] Traditional bonding methods use adhesives, but under high-frequency vibration and prolonged use, planar bonding is prone to insufficient bonding strength or adhesive layer aging, affecting the accuracy of tactile feedback. In some embodiments of this invention, an adhesive is used between the fixing part 21 and the ceramic component 1, and a groove is formed on the bonding side of the fixing part 21 to the ceramic component 1. Specifically, a high-strength adhesive can be selected to ensure that the fixing part 21 and the ceramic component 1 can withstand high-amplitude, high-frequency vibration transmission and maintain a firm bond under long-term cyclic loads. The groove on the bonding surface of the fixing part 21 increases the bonding area, providing stronger mechanical bonding performance compared to traditional smooth bonding surfaces. The presence of the groove enhances the friction between the interfaces, effectively reducing slippage during vibration transmission and improving the response efficiency and stability of tactile feedback.

[0030] In some embodiments of this utility model, such as Figure 2 As shown, the conductive part 23 is shaped like a spherical crown, and at least one stress relief groove 23a is provided on the conductive part 23. The stress relief groove 23a is located between the fixed part 21 and the vibrating part 22. The stress relief groove 23a has a widening structure, with the width near the fixed part 21 being greater than the width near the vibrating part 22.

[0031] The conductive part 23 is a smooth, continuous curved surface formed in one piece. The shape of the conductive part 23 is a spherical crown. Specifically, the generatrix length of the conductive part 23 and the angle formed between the generatrix and the fixed part 21 are key parameters for controlling the vibration force. The longer the generatrix length and the smaller the angle, the greater the vibration force generated by the conductive part 23; conversely, the smaller the angle, the smaller the vibration force. The spherical crown conductive part 23 does not have any abrupt changes in geometry or sharp changes in curvature. Its continuous and smooth characteristics ensure that the internal stress can achieve a smooth transition and uniform distribution during vibration, thus fundamentally eliminating the stress concentration phenomenon caused by sharp corners in traditional technical solutions. Due to the elimination of stress concentration points, the risk of fatigue crack initiation is minimized. Finite element analysis and accelerated life testing have verified that, under the same vibration displacement conditions, the fatigue life of the spherical crown conductive part 23 in this invention is more than an order of magnitude longer than that of traditional conductive surface structures with geometrical abrupt changes. The transmission component 2 can achieve strong tactile feedback and ultra-long service life without increasing material thickness or sacrificing vibration displacement amplitude, thus resolving the contradiction between "high displacement" and "long service life" in miniaturized, high-performance tactile actuators.

[0032] A stress relief groove 23a is formed on the conduction section 23 and positioned between the fixing section 21 and the vibration section 22. This design is an optimization and improvement to address fatigue damage caused by stress concentration under high cyclic loading. It smoothly guides and redistributes the stress flow within the conduction section 23, preventing new stress concentration points from appearing at the root of the connection between the stress relief groove 23a and the fixing section 21. The holes in the stress relief groove 23a provide additional elastic space for the microscopic deformation generated by the conduction section 23 during vibration, releasing locally concentrated strain and further reducing the risk of fatigue damage to the material. It should be noted that the shape of the stress relief groove 23a is the portion between two arcs centered on the center of the vibration section 22 on a spherical crown, forming a trapezoidal, diffused structure.

[0033] In some embodiments of this utility model, such as Figure 3As shown, the cross-section of the conductive part 23 perpendicular to the fixed part 21 is a wave-shaped structure, which includes at least one set of first broken line segments 23b and second broken line segments 23c. The alternating distribution of the first and second broken lines enhances the flexibility and uniformity of stress distribution of the conductive part 23 during vibration. The wave-shaped structure possesses inherent elastic properties, effectively absorbing and dispersing stress loads on the surface of the conductive part 23 during high-frequency vibration. The arrangement of each broken line segment allows the structure to exhibit more deformable channels under stress, distributing stress more evenly and reducing the burden on any single part. Especially during vibration load transition, the wave-shaped structure can buffer stress concentration caused by deformation gradients, thereby reducing the probability of fatigue crack formation.

[0034] To prevent stress concentration, fatigue cracks, or uneven deformation in the conductive portion 23 with the first and second bends, reference is made to some embodiments of this invention. Figure 3 As shown, the first segment 23b forms a first angle with the fixed part 21 ranging from 15° to 30°, and the second segment 23c forms a second angle with the fixed part 21 ranging from 5° to 15°. The first angle is larger than the second angle. The different angles between the first and second segments form a wave-shaped transmission part 23 with crests and troughs. The larger first angle provides greater structural flexibility, effectively alleviating stress concentration during initial force transmission and enhancing the overall structure's adaptability to impact loads. As the force is further transmitted, the smaller second angle gradually converges the stress flow, causing the transmission part 23 to gradually soften during dynamic influence, resulting in more natural and uniform stress dissipation. The design of the gradually changing angle forms a non-linear stress release path, preventing excessive concentration of force at any point when the force is transmitted from the fixed part 21 to the vibrating part 22, thereby improving the overall structure's durability and dynamic adaptability.

[0035] In some embodiments of this invention, the ratio of the projected length of the first fold line on the plane of the fixed part 21 to the projected length of the second fold line on the plane of the fixed part 21 is 1:2 to 1:3. Enhanced mechanical performance is achieved through precise geometric control. The longer second fold line, compared to the shorter first fold line, plays a greater role in buffering and adapting during force transmission. Especially during the transmission of dynamic loads, this asymmetrical length ratio effectively reduces stress concentration. The proportional control of the projected lengths ensures stress dispersion over a wider range along the transmission path, enabling the structure to achieve better stability under vibration-induced stress overload. This not only optimizes the stress mode but also improves the dynamic performance and tactile feedback accuracy of the entire component, extending the service life of the device.

[0036] In the above technical solution, the first included angle is larger than the second included angle, and the projected length of the second broken line on the plane where the fixed part 21 is located is greater than the projected length of the first broken line on the plane where the fixed part 21 is located. The longer lever arm with a smaller angle, and the projected length of the second included angle and the first broken line on the plane where the fixed part 21 is located, ensure extremely high displacement amplification and strong tactile sensation. The larger first included angle and the shorter projected length of the second broken line on the plane where the fixed part 21 is located provide a stable base, avoiding excessive stress at the trough inflection point. The stress during vibration is dispersed into multiple peaks and troughs, avoiding stress concentration and providing excellent fatigue resistance. At the same time, the wave-shaped structure can efficiently transfer energy directionally from the bottom to the top vibration surface. The wave shape can produce a larger overall displacement than a spherical crown shape of the same height, and the tactile sensation may be stronger.

[0037] In some embodiments of this invention, the conductive part 23 is shaped like an elliptical crown. The elliptical crown not only provides significant mechanical advantages in its streamlined structure, but also endows the structure with unique stiffness anisotropy due to the different radii of curvature along its major and minor axes. This asymmetry gives the elliptical crown a significant advantage over traditional circular structures in the directional transmission of vibrational energy. The elliptical crown exhibits lower bending stiffness along its minor axis and higher bending stiffness along its major axis. When the piezoelectric ceramic drives the elliptical conductive part 23, vibrational energy is more easily transmitted and amplified along the minor axis, where stiffness is lowest, thereby achieving directional vibrational energy transmission. This means that the vibrational energy is no longer uniformly radiated as in a circular structure, but is instead concentrated and guided in a specific direction.

[0038] Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A piezoelectric ceramic tactile feedback amplification structure, characterized in that, include: A ceramic component includes multiple ceramic sheets, wherein the electrodes of two adjacent ceramic sheets are opposite in polarity and interconnected, and an external electrode is provided on the outside of each ceramic sheet; The conductive component includes a fixed part that is parallel to and connected to the surface of the ceramic component, a vibrating part disposed at the center of the conductive component, and a conductive part that connects the vibrating part and the fixed part. The conductive part and the fixed part form an angle between them, the angle ranging from 1° to 10°.

2. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, The ceramic sheet has an internal electrode structure, and two adjacent ceramic sheets are riveted together or fixedly connected at the side ends.

3. The piezoelectric ceramic tactile feedback amplification structure according to claim 2, characterized in that, The external electrodes are disposed on both sides of the ceramic sheet, or on the upper and lower surfaces of the ceramic sheet, and the external electrodes are in communication with the internal electrodes.

4. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, The thickness of a single ceramic sheet ranges from 15 mm. Up to 100 .

5. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, An adhesive is present between the fixing part and the ceramic component, and a groove is formed on the side of the fixing part that is bonded to the ceramic component.

6. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, The conductive part is shaped like a spherical crown, and at least one stress relief groove is provided on the conductive part. The stress relief groove is located between the fixed part and the vibrating part. The stress relief groove has a widening structure, with the width near the fixed part being greater than the width near the vibrating part.

7. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, The cross-section of the conductive part perpendicular to the fixed part is a wave-shaped structure, and the wave-shaped structure includes at least one set of first broken line segments and second broken line segments.

8. The piezoelectric ceramic tactile feedback amplification structure according to claim 7, characterized in that, The first broken line segment forms a first angle with the fixing part ranging from 15° to 30°, and the second broken line segment forms a second angle with the fixing part ranging from 5° to 15°, wherein the first angle is greater than the second angle.

9. The piezoelectric ceramic tactile feedback amplification structure according to claim 8, characterized in that, The ratio of the projection length of the first broken line on the plane where the fixed part is located to the projection length of the second broken line on the plane where the fixed part is located is 1:2 to 1:

3.

10. The piezoelectric ceramic tactile feedback amplification structure according to claim 1, characterized in that, The conductive part is elliptical in shape.

Images