Disclosure of Invention
Accordingly, it is desirable to provide a haptic feedback module, a membrane keyboard and an electronic device that can reduce the thickness of a conventional keyboard.
A haptic feedback module includes at least two stacked conductive films,
the conductive films comprise a thin film insulating layer, a conductive electrode layer and an elastic layer which are arranged in a stacked mode, wherein the elastic layer comprises mutually independent columnar elastic bodies, and the thin film insulating layer of one conductive film of adjacent conductive films is adjacent to the elastic layer of the other conductive film; by applying adjustable voltage signals with different polarities to the conductive electrode layers in the adjacent conductive films, when the tactile feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force.
According to the tactile feedback module, the voltage signals with different polarities are applied to the conductive electrode layers in the adjacent conductive films, so that when the tactile feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic bodies are fed back to fingers of a user to form tactile feedback. The deformation quantity change of the voltage control columnar elastic body between the conductive electrode layers is changed to carry out touch feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in the touch feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. Because the voltage between the conductive electrode layers can be adjusted, the vibration sensation can be adjusted.
In one embodiment, the vibration amplitude of the columnar elastic body increases as the voltage between the conductive electrode layers increases. The vibration amplitude of the columnar elastic body can be controllably adjusted by controlling the voltage change between the conductive electrode layers, and the operation is simple, convenient and reliable.
In one embodiment, the conductive electrode layer comprises a driving part and an electrode part which are electrically connected, the thin film insulation layer, the driving part of the conductive electrode layer and the elastic layer are arranged in a laminated manner, and the electrode parts of the conductive electrode layers with the same voltage polarity are respectively used as a positive electrode and a negative electrode for inputting a driving signal of the tactile feedback module.
The thin film insulating layer, the driving part of the conductive electrode layer and the elastic layer are arranged in a stacked mode, so that the product is prevented from being separated due to vibration of the product in the use vibration process, and the effect of a fixing structure is achieved. The electrode part leading out of the conductive electrode layer is attached to obtain a positive electrode and a negative electrode input by a driving signal of the touch feedback module, so that the driving signal is accessed to adjust the voltage between the conductive electrode layers, and the convenience of driving control of the touch feedback module is improved.
In one embodiment, the elastic layer is made of an elastic silica gel material or a magnetorheological elastomer material. The elastic layer is made of elastic silica gel and has good elastic deformation capacity. The elastic layer is made of a magnetorheological elastomer material, and can effectively add the action of a magnetic field under the action of an electric field, so that the deformation rebound speed is increased, and the recovery and rebound effects of the elastic layer are increased.
In one embodiment, the elastic layer has a thickness of 20 microns to 100 microns. The thickness design of elastic layer is 20 microns-100 microns, avoids thickness to hang down to influence touch-control feedback effect excessively, still avoids the thickness too high simultaneously to lead to the excessive increase of thickness of tactile feedback module.
A film keyboard comprises a controller, a voltage adjusting component and the touch feedback module, wherein the voltage adjusting component is connected with the controller, the controller is connected with a conductive electrode layer of the touch feedback module, the voltage adjusting component is used for sending a voltage adjusting instruction to the controller, and the controller is used for adjusting the voltage of a driving signal transmitted to the conductive electrode layer according to the voltage adjusting instruction.
According to the film keyboard, the voltage signals with different polarities are applied to the conductive electrode layers in the adjacent conductive films, so that when the touch feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic bodies are fed back to fingers of a user to form touch feedback. The deformation quantity change of the voltage control columnar elastic body between the conductive electrode layers is changed to carry out touch feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in the touch feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. In addition, the user can input a voltage adjusting instruction through the voltage adjusting component according to actual requirements to control the voltage of the driving signal transmitted to the conductive electrode layer, so that different tactile feedback resilience is realized, the user can experience different tactile feedback force, and the use is more convenient.
In one embodiment, the membrane keypad further comprises a voltage control circuit connecting the controller and the conductive electrode layer. The controller controls the voltage amplitude value of the conductive electrode layer transmitted to the touch feedback module by the voltage control circuit according to the voltage adjusting instruction, so that the driving voltage of the conductive electrode layer is adjusted, and the control is convenient and reliable.
In one embodiment, the voltage control circuit includes a switching tube Q1, a light emitting diode red, and a resistor R2, a control terminal of the switching tube Q1 is connected to the controller, an input terminal of the switching tube Q1 is connected to a power supply terminal, an output terminal of the switching tube Q1 is connected to an anode of the light emitting diode red, and a cathode of the light emitting diode red is connected to the conductive electrode layer and is grounded through the resistor R2.
The controller can change the voltage transmitted to the conductive electrode layer by controlling the on-off frequency of the switch tube Q1, and the light-emitting diode REDLED emits light to play an indicating role when the voltage is transmitted to the conductive electrode layer, so that the operation of a user is facilitated.
In one embodiment, the voltage adjustment component is a voltage adjustment button. The controller controls the voltage of the driving signal transmitted to the conductive electrode layer according to the voltage adjusting instruction sent by the voltage adjusting button, and different tactile feedback resilience is achieved. And the voltage is adjusted by adopting the voltage adjusting button, so that the operation is simple, convenient and quick.
An electronic device comprises the film keyboard.
According to the electronic equipment, the voltage signals with different polarities are applied to the conductive electrode layers in the adjacent conductive films, so that when the touch feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic bodies are fed back to fingers of a user to form touch feedback. The deformation quantity change of the voltage control columnar elastic body between the conductive electrode layers is changed to carry out touch feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in the touch feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. In addition, the user can input a voltage adjusting instruction through the voltage adjusting component according to actual requirements to control the voltage of the driving signal transmitted to the conductive electrode layer, so that different tactile feedback resilience is realized, the user can experience different tactile feedback force, and the use is more convenient.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
In one embodiment, a haptic feedback module is provided, which comprises at least two stacked conductive films, as shown in fig. 1, the conductive films comprise a thin film insulation layer 110, a conductive electrode layer 120 and an elastic layer 130, which are stacked, wherein the elastic layer 130 comprises mutually independent columnar elastic bodies, and the thin film insulation layer 110 of one conductive film of the adjacent conductive films is adjacent to the elastic layer 130 of the other conductive film; by applying adjustable voltage signals with different polarities to the conductive electrode layers 120 in the adjacent conductive films, the columnar elastic bodies generate vibration feedback under the action of an electric field force when the tactile feedback module senses touch pressure.
Wherein, the external controller can control the input of the driving signal to the conductive electrode layer 120 of each conductive film in the haptic feedback module, so that the voltage polarities of the two conductive electrode layers 120 of the adjacent conductive films are opposite. Further, the voltage between the two conductive electrode layers 120 of the adjacent conductive films may also be controlled to periodically change, so that the vibration amplitude of the elastic layer 130 between the conductive electrode layers 120 also periodically changes.
Specifically, the thin film insulation layer 110 is located on the outermost layer of the conductive film, and the thin film insulation layer 110 is made of a non-conductive material on the contact surface between the conductive electrode layer 120 and a user, so that the insulation protection effect is achieved, meanwhile, the thin film insulation layer can be separated from the outside air, the conductive electrode layer 120 is prevented from being oxidized, and the waterproof evasion effect is achieved. The conductive electrode layers 120 in each conductive film are correspondingly arranged, an elastic layer 130 is arranged between every two adjacent conductive electrode layers 120, the vibration amplitude of the elastic layer 130 between the two adjacent conductive electrode layers 120 is periodically changed along with the periodic change of the voltage between the two adjacent conductive electrode layers 120, and the deformation quantity change of the elastic layer 130 is fed back to the finger of the user to form tactile feedback.
In the tactile feedback module, voltage signals with different polarities are applied to the conductive electrode layers 120 in the adjacent conductive films, so that when the tactile feedback module senses touch pressure, the columnar elastic body generates vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic body are fed back to a finger of a user to form tactile feedback. The deformation change of the voltage control columnar elastic body between the conductive electrode layers 120 is changed to carry out tactile feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in a tactile feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. Because the voltage between the conductive electrode layers 120 is adjustable, the vibration sensation can be adjusted.
The specific manner in which the vibration amplitude of the columnar elastic body varies with the voltage between two adjacent conductive electrode layers 120 is not exclusive, and in the present embodiment, the vibration amplitude of the columnar elastic body increases with the increase in the voltage between the conductive electrode layers 120. The vibration amplitude of the columnar elastic body can be controllably adjusted by controlling the voltage change between the conductive electrode layers 120, and the operation is simple, convenient and reliable.
The specific types and thicknesses of the thin film insulation layer 110, the conductive electrode layer 120 and the elastic layer 130 are not exclusive, and in one embodiment, the thin film insulation layer 110 may be a PET material layer, and the thin film insulation layer 110 is made of PET, so that the insulation performance is good and the safety in use is high. The thickness of the thin film insulating layer 110 may be designed to be 50 um. The conductive electrode layer 120 may be a carbon paste layer or a silver paste layer, and the thickness of the conductive electrode layer 120 may be about 10 um. The conductive electrode layer 120 is a carbon paste layer or a silver paste layer, has high conductivity, and can be matched with the overall structure of the keyboard for shape adjustment. The elastic layer 130 may be made of an elastic silicone material, for example, a silicone layer made of PDMS (polydimethylsiloxane), and has a good elastic deformation capability. The PDMS material is an elastic silica gel material with high dielectric constant and has high resilience.
The elastic layer 130 may also be made of a magnetorheological elastomer, in which micrometer-sized ferromagnetic particles are doped into a high molecular polymer and cured in a magnetic field environment, so that the particles in the matrix have a chain or columnar structure. The elastic modulus of the magnetorheological elastomer can be changed along with the intensity of an external magnetic field, and the magnetorheological elastomer not only has the high technical characteristics of controllability, reversibility, quick response and the like, but also has the unique advantages of good stability and the like. The elastic layer 130 is made of a magnetorheological elastomer material, and can effectively add a magnetic field under the action of an electric field, so that the deformation rebound speed is increased, and the recovery and rebound effects of the elastic layer are increased. The elastic layer 130 is made of a magnetorheological elastomer material, and can effectively add a magnetic field under the action of an electric field, so that the deformation rebound speed is increased, and the recovery and rebound effects of the elastic layer are increased.
In one embodiment, the thickness of the elastic layer 130 is 20 microns to 100 microns. The thickness of the elastic layer 130 is designed to be 20-100 micrometers, so that the influence of too low thickness on the touch feedback effect is avoided, and the excessive increase of the thickness of the touch feedback module caused by too high thickness is also avoided.
Further, the thickness of the elastic layer 130 may be specifically 30um to 50 um. The thickness of the elastic layer 130 is designed to be 30um-50um, and deformation quantity change can be ensured to be generated for touch feedback of fingers of a user while the thickness of the keyboard is effectively reduced according to the voltage change between the conductive electrode layers 120. The single-layer thin film insulation layer 110, the single-layer conductive electrode layer 120 and the single-layer elastic layer 130 are sequentially overlapped to form a single product structure, namely a conductive film, and the multiple product structures are overlapped in a staggered mode to obtain the touch feedback module.
The specific structure of the conductive electrode layer 120 is not exclusive, and in one embodiment, the conductive electrode layer 120 includes a driving portion and an electrode portion electrically connected to each other, the thin film insulation layer 110, the driving portion of the conductive electrode layer 120, and the elastic layer 130 are stacked, and the electrode portions of the conductive electrode layer 120 with the same voltage polarity are attached to each other and respectively serve as positive and negative electrodes for inputting a driving signal of the haptic feedback module.
Specifically, the number of the electrode portions of the conductive electrode layer 120 may be one or more, for example, when the number of the electrode portions is two, the electrode portions may be designed at opposite sides of the driving portion of the conductive electrode layer 120. Specifically, as shown in fig. 2, taking the number of electrode portions of the conductive electrode layer 120 as an example, the multilayer conductive films 100 may be sequentially stacked by rotating 180 ° in a staggered manner, and then bonded to reduce the thickness after the stacking of the multilayer product structure is completed. The electrode part 140 on the same side is attached to serve as a positive electrode/negative electrode for inputting a driving signal of the tactile feedback module, and the electrode part 140 on the other side is attached to serve as a negative electrode/positive electrode for inputting a driving signal of the tactile feedback module. As shown in fig. 3, the electrode portions 140 extending from both sides of the stacked structure are used as positive and negative electrodes to which driving signals are input, respectively.
In this embodiment, the thin film insulating layer 110, the driving portion of the conductive electrode layer 120, and the elastic layer 130 are stacked, so as to prevent the product from being separated due to vibration of the product during the use vibration process of the product, thereby playing a role of a fixing structure. The electrode part 140 of the lead-out conductive electrode layer 120 is attached to obtain a positive electrode and a negative electrode for inputting a driving signal of the tactile feedback module, so that the driving signal is accessed to adjust the voltage between the conductive electrode layers 120, and the convenience of driving control of the tactile feedback module is improved.
In one embodiment, as shown in fig. 4, bonding portions corresponding to the electrode portions of the conductive electrode layer 120 may also be disposed on two opposite sides of the elastic layer 130, after the thin film insulation layer 110, the conductive electrode layer 120, and the elastic layer 130 are sequentially stacked, the electrode portions of the conductive electrode layer 120 located on the same side are bonded by the bonding portions of the elastic layer 130, so as to avoid the bonding effect being affected by an excessively large height difference between the two conductive electrode layers 120.
In addition, the lamination mode among the thin film insulation layer 110, the conductive electrode layer 120 and the elastic layer 130 is not unique, and in this embodiment, the thin film insulation layer 110, the conductive electrode layer 120 and the elastic layer 130 are laminated and bonded by using a double-sided adhesive tape or a water adhesive tape, so as to improve the fixing reliability of the haptic feedback module.
In one embodiment, the thin film keyboard comprises a controller, a voltage regulating component and the tactile feedback module, wherein the voltage regulating component is connected with the controller, the controller is connected with the conductive electrode layer of the tactile feedback module, the voltage regulating component is used for sending a voltage regulating command to the controller, and the controller is used for regulating the voltage of a driving signal transmitted to the conductive electrode layer according to the voltage regulating command.
Specifically, the voltage regulating assembly can adopt a voltage regulating button, and the controller controls the voltage of the driving signal transmitted to the conductive electrode layer according to a voltage regulating instruction sent by the voltage regulating button so as to realize different tactile feedback resilience forces. And the voltage is adjusted by adopting the voltage adjusting button, so that the operation is simple, convenient and quick.
In one embodiment, the membrane keypad further comprises a voltage control circuit, the voltage control circuit connecting the controller and the conductive electrode layer. The controller controls the voltage amplitude value transmitted to the conductive electrode layer by the voltage control circuit according to the voltage adjusting instruction, so that the driving voltage of the conductive electrode layer is adjusted, and the control is convenient and reliable. It is understood that in other embodiments, the controller may transmit the corresponding driving voltage to the conductive electrode layer directly according to the voltage adjustment command.
In one embodiment, the number of the haptic feedback modules is two or more, and the controller is connected to the conductive electrode layers of the haptic feedback modules through the voltage control circuit for controlling the voltage control circuit to provide different driving voltages for the haptic feedback modules. Different driving voltages are provided for different touch feedback modules in the membrane keyboard to change the maximum deformation amount of the elastic layer in each touch feedback module, so that different touch feedback resilience is realized, a user can feel different touch feedback, the user can conveniently identify different touch feedback modules, different touch feedback resilience can be realized by adjusting the driving voltages for different touch feedback modules according to the user requirements, and the user can experience different touch feedback, so that the membrane keyboard is more convenient to use.
In one embodiment, the voltage control circuit includes a switching tube Q1, a light emitting diode red, and a resistor R2, wherein a control terminal of the switching tube Q1 is connected to the controller, an input terminal of the switching tube Q1 is connected to a power supply terminal, an output terminal of the switching tube Q1 is connected to an anode of the light emitting diode red, and a cathode of the light emitting diode red is connected to the conductive electrode layer and is grounded through a resistor R2. The controller can change the voltage transmitted to the conductive electrode layer by controlling the on-off frequency of the switch tube Q1, and the light-emitting diode REDLED emits light to play an indicating role when the voltage is transmitted to the conductive electrode layer, so that the operation of a user is facilitated.
According to the film keyboard, the voltage signals with different polarities are applied to the conductive electrode layers in the adjacent conductive films, so that when the touch feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic bodies are fed back to fingers of a user to form touch feedback. The deformation quantity change of the voltage control columnar elastic body between the conductive electrode layers is changed to carry out touch feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in the touch feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. In addition, the user can input a voltage adjusting instruction through the voltage adjusting component according to actual requirements to control the voltage of the driving signal transmitted to the conductive electrode layer, so that different tactile feedback resilience is realized, the user can experience different tactile feedback force, and the use is more convenient.
In one embodiment, an electronic device is also provided, which includes the membrane keyboard. The electronic device may be a notebook computer, a desktop computer, or other devices that require a keyboard to input information.
According to the electronic equipment, the voltage signals with different polarities are applied to the conductive electrode layers in the adjacent conductive films, so that when the touch feedback module senses touch pressure, the columnar elastic bodies generate vibration feedback under the action of an electric field force, and deformation quantity changes of the columnar elastic bodies are fed back to fingers of a user to form touch feedback. The deformation quantity change of the voltage control columnar elastic body between the conductive electrode layers is changed to carry out touch feedback, the limitation of a mechanical structure of a key in a traditional keyboard on thickness reduction is avoided, the thickness of each layer in the touch feedback module can be further compressed, and therefore the thickness of the keyboard is reduced. In addition, the user can input a voltage adjusting instruction through the voltage adjusting component according to actual requirements to control the voltage of the driving signal transmitted to the conductive electrode layer, so that different tactile feedback resilience is realized, the user can experience different tactile feedback force, and the use is more convenient.
In order to better understand the haptic feedback module, the membrane keypad and the electronic device, the following structural embodiments are explained in detail.
Due to the limitation of the structure, the conventional keyboard design realizes pressing and rebound feedback under the action force of matching the keycaps and the elastic structures with fingers, and comprises an elastic mechanism, a surface key frame and the keycaps according to the conventional keyboard structural design. In view of the material, the thickness of the keyboard cannot be compressed to a great extent, and the thickness of the existing keyboards is relatively high, although the thickness of the keyboard is reduced, the thickness of the existing keyboards still cannot be matched with that of the thin film due to the material.
Based on this, the film keyboard that this application provided and tactile feedback module thereof overturns the design of traditional keyboard, and the button is not using traditional key cap, rubber resilience and key frame isotructure, but uses the elastic silica gel material that has high dielectric constant, makes elastic layer 130 like PDMS, possess high resilience force material, and 30um-50um can be accomplished to thickness. The conductive electrode layer 120 is made of materials with good conductivity, such as carbon paste and silver paste, and the conductive electrode layer is strong in conductivity and can be made into various shapes such as surface bending by matching with the whole structure of the keyboard, and the thickness of the conductive electrode layer can be about 10 um. The thin film insulating layer 110 made of non-conducting materials is used on the contact surface of the electrode and a user to play an insulating protection role, and meanwhile, the thin film insulating layer can be separated from the outside air, so that the electrode is prevented from being oxidized, and a waterproof evasion role is played. The elastic layer 130, the conductive electrode layer 120 and the thin film insulation layer 110 are laminated layer by layer, and may be laminated and bonded by using a common double-sided adhesive tape or a water-based adhesive tape. The product separation caused by the vibration of the product in the use vibration process is avoided, the fixing structure effect is achieved, and the vibration sense is enhanced. In order to facilitate the use of a user, a voltage adjusting button which is convenient for the user to modify the magnitude of the tactile feedback force is designed, and the user can adjust the vibration feeling and the feedback strength which are suitable for the user experience according to the actual requirement.
As shown in fig. 1, a single product structure (i.e., a conductive film 100) stack comprises a thin film insulating layer 110 (e.g., a PET layer), a conductive electrode layer 120 (e.g., a carbon paste, a silver paste layer), and an elastic layer (e.g., a PDMS layer) 130 in this order. As shown in fig. 2, the multiple product structures are stacked in a staggered manner, and the number of stacked layers can be increased or decreased appropriately according to the user experience, for example, about 8 layers can be used. The multilayer products are sequentially and alternately rotated by 180 degrees for superposition, and the structure shown in figure 2 is formed after superposition. After a plurality of products are stacked, a finished product with reduced gap and reduced thickness is formed by adhering water adhesive or double-sided adhesive, as shown in fig. 3, electrodes extending out from two sides of the product are respectively used as positive and negative electrodes for inputting driving signals, the input testing signals generally adopt unipolar triangular wave periodic signals, the frequency generally adopts about 20-200Hz, and the frequency of a traditional keyboard, such as a mechanical keyboard, is simulated.
After the multi-layer product is stacked to form the tactile feedback module, the input signal is respectively connected to two ends of the tactile feedback module, and the electrode parts on two sides in the tactile feedback module shown in fig. 3 are respectively used as positive and negative electrodes. Input signal referring to fig. 5, the input signal divides four different control sampling points in one period: t1, T2, T3 and T4 are used to briefly describe the configuration of the haptic feedback module under different driving voltages. Fig. 6 to 8 are transient diagrams of dynamic changes of the tactile feedback module under different driving signals, fig. 6 is an initial state in which the tactile feedback module starts to receive an electric field force, fig. 7 is a state in which the electric field force is the maximum, and the cylindrical elastic body 132 (specifically, a silica gel column) receives the maximum electric field force. Fig. 8 shows the original state of the pillar-shaped elastic body 132 which is gradually rebounded by its own rebounding force as the electric field force is gradually reduced. The specific process is as follows:
a) the method comprises the following steps T1-T2 state. At time T1, the silica gel column morphology was not deformed for a while as shown in fig. 6, at time T1-T2, the electric field force gradually increased, the electrostatic attraction between the two conductive electrode layers 120 gradually increased, and a gradually increasing force was applied to the silica gel column, at time T2, the electric field force was the greatest, the attraction between the two conductive electrode layers 120 was the greatest, and at this time, the amount of deformation of the column was the greatest, as shown in fig. 7.
b) The method comprises the following steps T2-T3 state. At the time T2 to T3, the electric field force gradually decreases, the adsorption force between the two conductive electrode layers 120 also gradually decreases, the silica gel column slowly rebounds according to its own resilience, and when the driving signal is at the time T3, the silica gel column rebounds to the maximum, as shown in fig. 8.
c) The method comprises the following steps T3-T4 state. At this time, the input signal is substantially 0, and there is substantially no electric field force between the two conductive electrode layers 120, so there is no electrostatic adsorption force, and the original initial state of the silica gel column is still maintained.
d) The method comprises the following steps The signals in the stages T1 to T4 vary in period, and the frequency of the input signal shown in fig. 5 is about 50 Hz. Wherein the frequency of the input signal can be selected to be 20Hz-200Hz, and the signal source with different frequency can be input according to different user experiences, for example, if the user wants to experience stronger vibration, the frequency can be increased to be larger. When the user's finger contacts the tactile feedback module, the input signal changes periodically as shown in fig. 5, the silicone pillar changes from 0 deformation to the maximum deformation all the time, the feeling fed back to the finger is referred to as tactile feedback for short, as shown in fig. 9, a schematic diagram of the tactile feedback module contacted by the finger when the deformation of the elastic layer 130 is zero, and fig. 10 is a schematic diagram of the tactile feedback module contacted by the finger when the deformation of the elastic layer 130 is maximum.
As shown in fig. 11, the structural design diagram of the membrane keyboard is that the bottom of each letter and symbol key 200 (such as letters a, B, C … …, etc.) respectively uses the finished structure after stacking the products shown in fig. 3, each letter or key respectively pulls out the corresponding electrode, and different driving signals are respectively input through the adjustment control of the voltage adjustment assembly 210. Therefore, in the use process of each key, different driving voltages can be input according to the experience requirements of users, and different tactile feedbacks are obtained.
And (3) performing stress analysis on the product, wherein one force is an electric field force to ensure the adsorption acting force between the two conductive electrode layers 120, the other force is a column bounce force with the opposite direction, the electric field force F is (U2K Epsilon R S1)/(d 2Y S2), wherein U is a driving voltage applied to two ends of the product, K is an electrostatic force constant, Epsilon R is the total dielectric constant of the laminated material, S1 is the effective area of the electric field, d is the distance between the two electrodes, Y is the elastic modulus of the column, and S2 is the cross sectional area of the column. The application mainly modifies the magnitude of the input voltage so as to achieve different haptic feedback strengths, and the principle of voltage modification is briefly described as follows:
as shown in fig. 12, a control terminal of the switching tube Q1 is connected to the controller, an input terminal of the switching tube Q1 is connected to the power source VCC, an output terminal of the switching tube Q1 is connected to an anode of the light emitting diode red, and a cathode of the light emitting diode red is connected to the conductive electrode layer 120 and is grounded via the resistor R2. Specifically, Q1 is a MOS transistor for controlling a duty cycle control switch of the input power supply (of course, this may be a similar device with NMOS/PMOS/CMOS switch control function), the led is used as a prompt signal, and the IO1 port is connected to the controller. When the MOS transistor is turned on by a signal received from the IO1 port, a power is input to the product terminal (specifically, to the conductive electrode layer 120 in each conductive film 100 at the bottom of the key 200), and the product is driven to operate normally. As shown in fig. 11, a physical button (i.e. the voltage regulating component 210) for voltage output size regulation is reserved on the keyboard, and the user temporarily regulates the effective duty ratio of the IO1 port, so as to implement the voltage size change, and fig. 13 is a timing chart of the output of the IO1 port. As shown in fig. 14 and 15, the voltage outputs corresponding to 50% and 100% duty cycles respectively correspond to 50% and 100% electric field forces, and the haptic feedback forces are also about 50% and 100%.
Above-mentioned film keyboard and tactile feedback module thereof adopts silica gel layer (like the PDMS layer of 30 um), conducting electrode layer (like the carbon thick liquid or the silver thick liquid layer of 10 um) and thin film insulation layer (like the PET layer of 50 um), and monolithic product gross thickness can accomplish about 0.1mm, can increase to 6 layers-10 layers for reinforcing the tactile feedback effect, and the whole thickness can accomplish below 1mm for the product is thinner, lighter. The solid keys can be added on the thin-film keyboard according to the requirements of users, different driving input voltages can be obtained by adjusting the solid keys, different touch feedback resilience can be realized by adjusting the driving voltage by different keys, and therefore the users can experience different touch feedback force. Meanwhile, different vibration senses can be experienced by the fingers according to requirements at different keys such as key letter symbols and the like. In addition, the outermost layer of the conductive electrode layer and the elastic layer is made of an insulating material, such as a PET (polyethylene terephthalate) material, so that the waterproof and dustproof purposes can be achieved, the service life of the product is prolonged, and the waterproof purpose is achieved.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.