Handwriting eliminating device and method for touch screen, electronic handwriting pen and pen cap of electronic handwriting pen

Abstract

The invention provides a handwriting eliminating device and method of a touch screen, an electronic handwriting pen and a pen cap of the electronic handwriting pen, the handwriting eliminating device comprises a trigger component and a strain component, the handwriting eliminating device can be applied to the electronic handwriting pen, and when the handwriting eliminating device is used for eliminating an image on the touch screen, the handwriting can be eliminated. The pressing part transmits force borne by the trigger part in contact with the touch screen to the strain induction assembly, and the strain induction assembly deforms according to the pressing force to generate an erasing signal corresponding to deformation. When the contact force between the trigger part and the touch screen is changed, the deformation degree of the strain sensing assembly is correspondingly changed, and a corresponding erasing signal is generated; the touch force of the trigger part and the touch screen is different, the strain sensing assembly can generate different erasing signals, a user can erase images on the touch screen in a grading mode by adjusting the contact force of the trigger part and the touch screen, and then erasing effects of different degrees are achieved.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a device and method for erasing handwriting on a touch screen, an electronic stylus pen and a pen cap thereof. Background Art

[0002] A touch screen, also known as a "touch screen" or "touch panel", is an inductive liquid crystal display device that can receive input signals such as contacts. When the graphic buttons on the screen are touched, vivid audio and video effects are produced through the liquid crystal display screen. It is mainly used in public information query, leadership office, industrial control, military command, electronic games, ordering songs and dishes, multimedia teaching, real estate pre-sales, etc.

[0003] With the continuous development of electronic technology, touch screens have become the most common image forming devices in people's lives. However, in actual use, users may draw erroneous audio and video images due to some unexpected situations such as accidental touches. In this case, a handwriting erasure device is needed to erase the erroneous audio and video images.

[0004] In the prior art, there are several erasing methods:

[0005] 1. Turn the stylus pen 180 degrees and use the end of the pen to press and erase on the screen. Pressing can make the contacts inside the end of the pen touch each other to realize action recognition, triggering the program to call the eraser function to realize erasing;

[0006] 2. The user taps or presses the specific touch area of ​​the electronic stylus. The stylus can detect the capacitance change caused by the touch input sensor over a period of time and interpret it as the user's gesture to trigger the eraser function.

[0007] In the first erasing method mentioned above, the same erasing mark will appear under different erasing forces, and the erasing effect is poor; in the second erasing method mentioned above, the same erasing mark will appear under different erasing forces, and the erasing effect is poor; its trigger position is generally placed within a distance from the front end of the stylus close to the pen tip, and the interactive program is recognized by regular tapping of the finger, the probability of accidental touch is high, and the eraser function is accidentally switched during writing with the electronic stylus.

[0008] Therefore, the handwriting erasing device in the prior art has the problem of poor performance. Summary of the invention

[0009] The embodiments of the present application provide a handwriting erasing device and method for a touch screen, an electronic stylus pen and a pen cap thereof, which solve the problem of poor performance of handwriting erasing devices in the prior art.

[0010] In a first aspect, an embodiment of the present application provides a handwriting erasing device for a touch screen, the handwriting erasing device comprising a trigger component and a strain component; wherein

[0011] The trigger component includes a trigger portion contacting the touch screen, and a pressing portion arranged inside the trigger portion;

[0012] The strain component includes a strain sensing component disposed opposite to the pressing portion; and

[0013] The trigger part contacts the touch screen and is subjected to force, and presses the strain sensing component through the pressing part. The strain sensing component deforms according to the pressing force applied by the pressing part and generates an erasing signal corresponding to the deformation. The erasing signal is used to eliminate the handwriting displayed on the touch screen.

[0014] By adopting the above technical scheme, when a handwriting erasing device is used to erase an image on a touch screen, the pressing portion transmits the force exerted by the trigger portion on the touch screen to the strain sensing component, and the strain sensing component deforms according to the pressing force to generate an erasing signal corresponding to the deformation; when the force exerted by the trigger portion on the touch screen changes, the degree of deformation of the strain sensing component also changes accordingly and generates a corresponding erasing signal; in this process, the contact force between the trigger portion and the touch screen is different, and the strain sensing component can generate different erasing signals. The user can achieve graded erasing of the image on the touch screen by adjusting the contact force between the trigger portion and the touch screen, thereby achieving erasing effects of different degrees, which is beneficial to improving the performance of the handwriting erasing device.

[0015] In some embodiments, the strain sensing assembly includes a strain substrate and a plurality of strain sensing elements, wherein the plurality of strain sensing elements are disposed on the strain substrate; wherein,

[0016] The multiple strain sensing elements are located in the same plane, a plane parallel to the plane where the multiple strain sensing elements are located is used as a projection plane, and the multiple strain sensing elements are evenly distributed in an array in the projection plane; and,

[0017] The projection of the pressing portion on the projection surface is located within the projection outer contours of the plurality of strain sensing elements on the projection surface.

[0018] By adopting the above technical solution, when the pressing part is subjected to the squeezing force of the trigger part at any position, the squeezing force can be applied to the strain sensing component. When the trigger part contacts the touch screen at any position, the strain sensing component can generate a corresponding erasing signal and be used to perform a corresponding erasing action on the handwriting displayed on the touch screen.

[0019] In addition, by configuring the strain sensing component to include multiple strain sensing elements, each strain sensing element can deform independently when subjected to force, thereby reducing the probability that when a certain position of the strain sensing component is deformed due to force, other positions are affected and deformed to generate an erroneous erase signal.

[0020] Therefore, the structure can not only ensure that the handwriting erasing device has a larger sensing range, but also improve the accuracy of the handwriting erasing device in performing the erasing action, which is conducive to further improving the performance of the handwriting erasing device.

[0021] In some embodiments, the strained substrate has a centrally symmetrical structure as a whole; and

[0022] The pressing portion is configured as a protruding structure protruding from the inner side of the trigger portion, the protruding direction of the protruding structure is perpendicular to the strain substrate, and the projection point of the geometric center of the end of the protruding structure on the projection plane coincides with the geometric center point of the strain substrate.

[0023] By adopting the above technical solution, by setting multiple strain sensing elements on the strain substrate, the strain substrate as a whole presents a centrally symmetrical structure, so that the multiple strain sensing elements can be arranged at various angles, so that when the trigger part is linked to the pressing part to squeeze the strain sensing component at any angle, the corresponding strain sensing element in the strain sensing component can be deformed and generate a corresponding erasure signal, and the user can perform the handwriting erasure action at any angle using the handwriting erasure device.

[0024] In addition, the pressing portion is set as a protruding structure protruding from the inner side of the trigger portion, and the projection point of the geometric center of the end of the protruding structure on the projection surface coincides with the geometric center point of the strain substrate. In this way, when the pressing portion applies pressing force to the corresponding strain sensing element at different angles, the pressing force applied to the corresponding strain sensing element will not be affected by the change in the pressing angle, thereby affecting the erasing effect of the handwriting erasing device.

[0025] In some embodiments, the strained substrate includes a plurality of substrate members arranged in pairs, and the plurality of substrate members are evenly arranged around a geometric center point of the strained substrate;

[0026] Every two strain sensing elements in the plurality of strain sensing elements constitute a pair of strain sensing elements, wherein at least one pair of strain sensing elements is attached to each substrate component in the plurality of substrate components.

[0027] By adopting the above technical solution, when the trigger part and the pressing part apply pressing force to the corresponding strain sensing element at different angles, the deformation amount of each strain sensing element is the same, thereby reducing the probability that the deformation amount difference of the strain sensing element is large when the trigger part is pressed at different angles and affects the erasure signal of the handwriting erasing device, which is beneficial to improving the erasure accuracy of the handwriting erasing device.

[0028] In some embodiments, each of the multiple strain sensing elements is configured as a resistance strain gauge, a pair of resistance strain gauges is attached to each of the multiple substrate components, and the pair of resistance strain gauges on each substrate component is electrically connected to the corresponding pair of auxiliary resistors to form a Wheatstone bridge circuit.

[0029] By adopting the above technical solution, by electrically connecting the resistance strain gauge with the corresponding pair of auxiliary resistors, each resistance strain gauge and the corresponding auxiliary resistor can form a half-bridge circuit of the Wheatstone bridge circuit, and the interference between the half-bridge circuits is relatively small.

[0030] In addition, when the resistance strain gauge changes due to the deformation of the strain steel sheet, since the auxiliary resistor is located outside the strain substrate, it is not disturbed and does not produce resistance changes, and can be used as a reference resistor.

[0031] In some embodiments, each of the plurality of strain sensing elements is configured as a resistance strain gauge, and each of the plurality of substrate components is provided with two pairs of the resistance strain gauges, and the two pairs of the resistance strain gauges are electrically connected to form a Wheatstone bridge circuit; and

[0032] The two pairs of resistance strain gauges in each Wheatstone bridge are arranged in a ring shape or side by side.

[0033] By adopting the above technical solution, the resistance strain gauges are arranged in a ring or side by side. In this way, when the strain steel gauge is deformed at any angle, the resistance strain gauge can change its resistance value in response to the deformation of the strain steel gauge, which is beneficial to improving the sensitivity of the strain component.

[0034] In some embodiments, the strain substrate is configured as a strained steel sheet.

[0035] By adopting the above technical solution, since the flexible circuit board is a flexible structure and the internal integrated circuit structure may be damaged after multiple squeezing, and may affect the circuit on the other hand, this structure can effectively protect the flexible circuit board and reduce the probability of damage and failure of the flexible circuit board after multiple uses.

[0036] In addition, when the strain steel sheet is subjected to impact force, the transmission loss of the impact force is small, and the conversion rate of the impact force into deformation is high. Even when the strain steel sheet is subjected to a small impact force, the resistance strain gauge can convert its deformation into an electrical signal, thereby generating an erasure signal for the handwriting erasure device, which is beneficial to improving the sensitivity of the strain component.

[0037] In some embodiments, the strain sensing component also includes a flexible circuit board, which includes a first part and a second part, the first part is stacked with the strain substrate and attached to a side of the strain substrate away from the pressing portion, and each of the multiple strain sensing elements is attached to a surface of the first part away from the strain substrate, so that the multiple strain sensing elements are arranged on the strain substrate through the first part of the flexible circuit board, and the second part is bent and extended toward one side of the first part and is located outside the strain substrate.

[0038] In some embodiments, when the handwriting erasing device is formed with a Wheatstone bridge circuit, an auxiliary resistor of the Wheatstone bridge circuit is disposed on the second portion of the flexible circuit board.

[0039] In some embodiments, the handwriting erasing device further includes a signal transmitting component, and the signal transmitting component is used to send an erasing signal to an electronic device using a touch screen.

[0040] In some embodiments, the handwriting erasing device further includes a sensing electrode, the sensing electrode constitutes the pressing portion, and the sensing electrode is electrically connected to the second portion of the flexible circuit board.

[0041] By adopting the above technical solution, since many conductors are arranged inside the touch screen and sensing electrodes are used, capacitance can be generated between the handwriting erasing device in the present application and the touch screen when the handwriting erasing device is close to the touch screen. No other operation is required in this process, and the handwriting erasing device can interact with the touch screen, thereby activating the pen eraser function of the electronic device using the touch screen, making it more convenient to use.

[0042] In some embodiments, the handwriting erasing device further includes an insulating member, which is disposed between the sensing electrode and the strain sensing component. The end of the sensing electrode is adapted to be fitted into a groove at the corresponding end of the insulating member, and an end of the insulating member away from the sensing electrode also forms a protruding structure aligned with the geometric center point of the strain substrate of the strain sensing component. When the triggering portion is subjected to force, the strain substrate of the strain sensing component is pressed by the protruding structure of the insulating member.

[0043] In some embodiments, a bracket is further included, the bracket having a hollow area or a sunken area, one end of each of the multiple substrate components away from the geometric center point is fixed to the bracket, and the other ends are connected to each other and suspended in the hollow area or the sunken area of ​​the bracket to form an end-fixed beam structure.

[0044] In some embodiments, the outer surface of the trigger portion has a soft protective layer.

[0045] In some embodiments, the device further includes a housing, wherein the trigger component and the strain component are fixed in the housing, and the trigger portion is partially exposed from the housing.

[0046] In some embodiments, the portion of the trigger portion exposed from the housing is in a truncated spherical structure, and the cross-sectional center angle of the truncated spherical structure is in the range of 90° to 150°.

[0047] By adopting the above technical solution, by setting the trigger part to a truncated spherical structure, and the cross-sectional center angle of the truncated spherical structure is in the range of 90° to 150°, the handwriting erasing device in the present application can have a larger erasing range.

[0048] In a second aspect, an embodiment of the present application further provides a pen cap of an electronic stylus pen, which is arranged at the end of the electronic stylus pen and is used to perform the pen erasing function of the electronic stylus pen; the pen cap includes the handwriting erasing device of the above-mentioned structural touch screen.

[0049] By adopting the above technical solution, by integrating the handwriting erasing device of the above structure into the pen cap of the electronic stylus, when realizing the handwriting erasing function, the handwriting erasing device of the above structure can not only achieve different degrees of erasing effects based on the size of the pressing force, but also realize multi-angle recognition and erasing. The pen cap of the electronic stylus adopts this structure, which can not only improve the functional diversification of the electronic stylus pen cap, but also improve the performance of the electronic stylus.

[0050] In a third aspect, an embodiment of the present application further provides an electronic stylus, including a pen body and a pen head arranged at one end of the pen body, including a pen cap of the above structure, and the pen cap can be plugged and connected to the other end of the pen body.

[0051] By adopting the above technical solution, the pen cap of the above structure can realize different degrees and multi-angle recognition based on the size of the pressing force to eliminate the handwriting on the touch screen, which can improve the performance of the electronic stylus.

[0052] In addition, by plugging and detaching the pen cap to the other end of the pen barrel, the pen cap can be used independently when the handwriting erasing function is used, which is more convenient to use.

[0053] In a fourth aspect, the present application also provides a method for erasing handwriting on a touch screen, which is applied to an electronic stylus pen. The electronic stylus pen with the above structure is used to perform a pen eraser function. The method for erasing handwriting on a touch screen includes:

[0054] Receiving a feedback signal from an electronic device using a touch screen to trigger a pen eraser function of the pen cap;

[0055] Detecting and sending electrical signal information indicating the force applied to the triggering part;

[0056] The target pressure information of the pen cap is determined according to the electrical signal information, and the target pressure information is sent to the electronic device, so that the electronic device determines the degree of erasure of the handwriting displayed on the touch screen according to the target pressure information; wherein the target pressure information includes the pressure size information of the pen cap.

[0057] By adopting the above technical solution, the handwriting erasing method can determine the degree of erasure of handwriting displayed on the touch screen based on the pressure information of the pen cap. When the handwriting erasing function is performed using the pen cap, different erasing effects can be achieved under different erasing force sizes.

[0058] In some embodiments, the strain sensing component includes a strain substrate and multiple strain sensing elements, and the multiple strain sensing elements are arranged on the strain substrate; the multiple strain sensing elements generate multiple electrical signal information according to the pressing force applied by the pressing part, and determine the target pressure information of the pen cap according to the multiple electrical signal information, and send the target pressure information to the electronic device, so that the electronic device determines the degree of erasure according to the target pressure information.

[0059] By adopting the above technical solution, the target pressure information of the pen cap is determined by multiple electrical signal information, so that the accuracy of the target pressure information can be guaranteed. Even if an error occurs in a certain electrical signal information, the method can reduce the degree of influence on the target pressure information.

[0060] In some embodiments, the plurality of strain sensing elements correspond to N Wheatstone bridge circuits, each Wheatstone bridge circuit outputs a bridge voltage, and the plurality of electrical signal information are N bridge voltages output by the N Wheatstone bridge circuits.

[0061] In some embodiments, determining the pressure information of the electronic stylus pen cap according to the plurality of electrical signal information includes:

[0062] The current angle information of the pen cap is determined according to the N bridge voltages; the current angle information is calculated according to the following formula:

[0063]

[0064] Among them, θ represents the angle between the current force direction of the pen cap and the axis of the pen cap; V2i-1 and V2i represent the current bridge voltages output by the two relatively set Wheatstone bridge circuits, 1≤i≤N; K is the correction coefficient;

[0065] Determine current voltage information according to N bridge voltages and current angle information;

[0066] The pressure magnitude information is determined based on the current voltage information and the calibration information; wherein the calibration information represents the one-to-one correspondence between different voltage information and different pressure information when the pen cap is subjected to force at a calibration angle; the calibration angle is configured as: the angle when the force direction of the pen cap coincides with the axis of the pen cap.

[0067] By adopting the above technical solution, the current angle information of the pen cap is determined according to N bridge voltages, the current voltage information is determined by using the N bridge voltages and the current angle information, and the pressure information is determined according to the current voltage information and the calibration information. In this way, the erasing effect can be compensated according to the different inclination angles of the pen cap (or it can be understood that the role of calculating the inclination angle is to provide compensation for the algorithm), avoiding the need to use a large erasing force due to the weak signal of the pen cap edge, so that under the same pressing force, a consistent erasing effect can be produced at different inclination angles. This is conducive to improving the accuracy of executing the handwriting erasing action on the touch screen.

[0068] In some embodiments, before receiving a feedback signal from an electronic device triggering a pen eraser function, the method further includes: sending a trigger signal for enabling the pen eraser function.

[0069] The beneficial effects of this application are:

[0070] Provided is a handwriting erasing device for a touch screen, comprising a trigger component and a strain component; the trigger component comprises a trigger portion in contact with the touch screen, and a pressing portion arranged inside the trigger portion; the strain component comprises a strain sensing component arranged opposite to the pressing portion; the trigger portion contacts the touch screen and is subjected to force, and the strain sensing component is pressed by the pressing portion, the strain sensing component is deformed according to the pressing force applied by the pressing portion and generates an erasing signal corresponding to the deformation, and the erasing signal is used to erase handwriting displayed on the touch screen.

[0071] When the handwriting erasing device is used to erase an image on the touch screen, the pressing portion transmits the force exerted by the trigger portion on the touch screen to the strain sensing component, and the strain sensing component deforms according to the pressing force to generate an erasing signal corresponding to the deformation; when the force exerted by the trigger portion on the touch screen changes, the degree of deformation of the strain sensing component also changes accordingly and generates a corresponding erasing signal; in this process, the contact force between the trigger portion and the touch screen is different, and the strain sensing component can generate different erasing signals. The user can achieve graded erasing of the image on the touch screen by adjusting the contact force between the trigger portion and the touch screen, thereby achieving erasing effects of different degrees, which is beneficial to improving the performance of the handwriting erasing device. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1a It is a schematic diagram of the writing state of the electronic stylus on the touch screen;

[0073] Figure 1b A schematic diagram of the erasing state of the electronic stylus on the touch screen;

[0074] Figure 2 This is the erasing effect diagram of a physical eraser;

[0075] Figure 3aIt is a schematic diagram of the exploded structure of a handwriting erasing device provided in one embodiment of the present application;

[0076] Figure 3b It is a cross-sectional structural diagram of a handwriting erasing device and a touch screen provided in one embodiment of the present application;

[0077] Figure 3c This is a schematic diagram of the principle of the handwriting erasing device provided by an embodiment of the present application in a non-pressed state;

[0078] Figure 3d This is a schematic diagram of the principle of a handwriting erasing device in a pressed state provided by an embodiment of the present application;

[0079] Figure 4a This is a schematic diagram of the structure of the strain sensing component in the embodiment of the present application;

[0080] Figure 4b This is a schematic diagram of the structure of the strain component and the pressing portion in the embodiment of the present application;

[0081] Figure 5a A schematic top view of a first implementation of a strained substrate provided in an embodiment of the present application;

[0082] Figure 5b A schematic top view of a second embodiment of a strained substrate provided in an embodiment of the present application;

[0083] Figure 5c A schematic top view of a third embodiment of a strained substrate provided in an embodiment of the present application;

[0084] Figure 5d A schematic top view of a fourth embodiment of a strained substrate provided in an embodiment of the present application;

[0085] Figure 6a A schematic diagram of the structure of a strain substrate and a resistance strain gauge provided in an embodiment of the present application;

[0086] Figure 6b A schematic diagram of the structure of a flexible circuit board provided in an embodiment of the present application;

[0087] Figure 7a A schematic diagram of the connection structure between the strain substrate and the auxiliary resistor provided in an embodiment of the present application;

[0088] Figure 7b is the circuit diagram of the Wheatstone bridge circuit;

[0089] Figure 7c A circuit diagram provided by an embodiment of the present application;

[0090] Figure 8a A schematic diagram of a structure of a strain substrate provided in an embodiment of the present application;

[0091] Figure 8b Another structural schematic diagram of a strain substrate provided in an embodiment of the present application;

[0092] Figure 8c A circuit diagram provided by another embodiment of the present application;

[0093] Figure 9a A schematic diagram of the structure of a resistance strain gauge provided in one embodiment of the present application;

[0094] Figure 9b A schematic diagram of the structure of a resistance strain gauge provided in another embodiment of the present application;

[0095] Fig.9c A strain principle diagram of a resistance strain gauge provided in an embodiment of the present application;

[0096] Fig.10 This is a schematic diagram of the connection structure between the sensing electrode and the flexible circuit board in the embodiment of the present application;

[0097] Fig.11 It is the schematic diagram of capacitive sensing;

[0098] Fig.12a A schematic diagram of the exploded structure of the handwriting erasing device provided in an embodiment of the present application;

[0099] Figure 12b A schematic cross-sectional view of a handwriting erasing device provided in an embodiment of the present application;

[0100] Fig.12c A schematic diagram of the top view of the handwriting erasing device provided in an embodiment of the present application;

[0101] Fig.12d A schematic diagram of the structure of a strain component provided in an embodiment of the present application;

[0102] Fig.12e A schematic diagram of the isometric structure of a handwriting erasing device provided in an embodiment of the present application;

[0103] Fig.12f A diagram showing the use status of the handwriting erasing device provided in an embodiment of the present application;

[0104] Fig.13 A partial cross-sectional structural schematic diagram of a handwriting erasing device provided in an embodiment of the present application;

[0105] Fig.14a A schematic diagram of the assembly structure of a pen cap provided in an embodiment of the present application;

[0106] Fig.14b A schematic cross-sectional view of a pen cap provided in an embodiment of the present application;

[0107] Fig.15a A schematic diagram of the assembly structure of the electronic stylus provided in an embodiment of the present application;

[0108] Fig.15b A schematic cross-sectional view of the electronic stylus provided in an embodiment of the present application;

[0109] Fig.16a A block diagram of the principle of the handwriting removal method provided in the embodiment of the present application;

[0110] Figure 16a' Another principle block diagram of a handwriting elimination method provided by an embodiment of the present application;

[0111] Fig.16b A flow chart of a handwriting removal method provided in an embodiment of the present application;

[0112] Fig.16c A schematic diagram of a use scenario of a handwriting removal method provided in an embodiment of the present application;

[0113] Fig.16d A schematic diagram of another scenario of using the handwriting removal method provided in one embodiment of the present application;

[0114] Fig.17a Schematic diagram of a bridge circuit in an embodiment of the present application;

[0115] Fig.17b A diagram of a pen cap model in an embodiment of the present application;

[0116] Fig.17c It is a schematic diagram of the force analysis of a certain point of the pen cap in the embodiment of the present application.

[0117] Description of reference numerals:

[0118] Description of the prior art reference numerals: 10 ′, electronic stylus;

[0119] 10A', pen tip; 10B', pen holder; 10C', pen cap;

[0120] 20', touch screen;

[0121] Description of the accompanying drawings in this application:

[0122] 10. Electronic stylus;

[0123] 10A, pen tip; 10B, pen holder; 10D, processor; 10E, wireless module;

[0124] 10C, pen cap; 101D, processor; 101E, wireless module;

[0125] 100. Handwriting erasing device;

[0126] 110. Trigger component;

[0127] 111. triggering part; 112. pressing part; 1121. protruding structure;

[0128] 120. Strain components;

[0129] 121. Strain sensing components;

[0130] 1211, strain sensing element; 1211A, resistance strain gauge;

[0131] 122. Strain substrate;

[0132] 1221, substrate component; 1222, strain steel sheet; 1223, flexible circuit board; 1223A, first part; 1223B, second part; 1224, auxiliary resistor; 122A, conductive foam;

[0133] 123. Bracket;

[0134] 130A, induction electrode;

[0135] 140. Insulation parts;

[0136] 141. groove; 142. protruding structure;

[0137] 150. Soft protective layer;

[0138] 160, housing;

[0139] 20. Touch screen;

[0140] 30. Electronic equipment;

[0141] 30A, processor; 30B, erasing module; 30C, wireless interface; 30D, display. DETAILED DESCRIPTION

[0142] The handwriting erasing device for a touch screen in the present application is used to erase handwriting or images on a touch screen, and the touch screen is applied to electronic devices, such as mobile phones, tablet computers, wearable devices, vehicle-mounted devices, augmented reality (AR) / virtual reality (VR) devices, laptop computers, ultra-mobile personal computers (UMPC), netbooks, personal digital assistants (PDA) and other electronic devices. The touch screen can also be called a touch panel, and the touch screen can perform a variety of operations, such as sending signals, receiving signals, etc. It should be understood that the interactive device can also include other units or modules. For example, if the interactive device is a smart phone, it can also include modules such as speakers, microphones, and light sensors.

[0143] The handwriting erasing device may be integrated into an electronic stylus pen used in conjunction with the touch screen. The electronic stylus pen may be an active capacitive stylus pen, but this application does not impose any limitation on this.

[0144] First, if Figure 1a to Figure 1b The usage scenarios of the electronic stylus are described.

[0145] Figure 1a This is a schematic diagram of the writing status of the electronic stylus on the touch screen. Figure 1b Schematic diagram of the erasing state of the electronic stylus on the touch screen.

[0146] like Figure 1a-1b As shown, the electronic stylus 10' comprises a pen body 10B', a pen head 10A' and a pen cap 10C' respectively arranged at both ends of the pen body 10B'. The writing end is the part of the pen head 10A', which is used for writing or drawing graphics on the touch screen 20'.

[0147] exist Figure 1a In the state shown, the electronic stylus 10 ′ uses the pen tip 10A′ to write on the touch screen 20 ′. During this process, the user may draw an erroneous audio and video image due to some unexpected situations such as accidental touch. In this case, a handwriting erasing device is required to erase the erroneous audio and video image.

[0148] At this time, the electronic stylus pen 10' can be rotated 180 degrees, so that the electronic stylus pen 10' is rotated to Figure 1b In the state shown, the erroneous audio and video images are eliminated by using the pen cap 10C at the end of the electronic stylus 10.

[0149] Further Figure 1bAs shown, when using the cap 10C at the end of the electronic stylus 10' to erase an erroneous audio or video image, the user may use an eraser according to the previous usage habits, such as Figure 2 As shown, Figure 2 This is an erasing effect diagram of a physical eraser. During the erasing process of a real pencil, different erasing marks will appear under different erasing forces. Similarly, the user can achieve the erasing effect by controlling the pressing force F on the pen cap 10C'.

[0150] However, the handwriting erasing device of the touch screen or the pen cap 10C' at the end of the electronic stylus 10' in the prior art cannot realize this function, cannot meet the use requirements of the user, and has the problem of poor use performance.

[0151] Based on this problem, the embodiments of the present application provide a handwriting erasing device and method for a touch screen, an electronic stylus and a pen cap thereof. When the handwriting erasing device is used to erase an image on the touch screen, the pressing portion transmits the force exerted by the trigger portion on the touch screen to the strain sensing component, and the strain sensing component deforms according to the pressing force to generate an erasing signal corresponding to the deformation; when the force exerted by the trigger portion on the touch screen changes, the degree of deformation of the strain sensing component also changes accordingly and generates a corresponding erasing signal; in this process, the contact force between the trigger portion and the touch screen is different, and the strain sensing component can generate different erasing signals. The user can achieve graded erasing of the image on the touch screen by adjusting the contact force between the trigger portion and the touch screen, thereby achieving erasing effects of different degrees, which is beneficial to improving the performance of the handwriting erasing device.

[0152] The structure and working principle of the handwriting erasing device provided in the embodiment of the present application are described in detail below with reference to the accompanying drawings.

[0153] See also Figure 3a-3d , Figure 3a It is a schematic diagram of the exploded structure of a handwriting erasing device provided in one embodiment of the present application; Figure 3b It is a cross-sectional structural diagram of a handwriting erasing device and a touch screen provided in one embodiment of the present application; Figure 3c is a schematic diagram of a handwriting erasing device provided by an embodiment of the present application in a non-pressed state; Figure 3d It is a schematic diagram of a pressed state of a handwriting erasing device provided by an embodiment of the present application.

[0154] like Figure 3a-Figure 3b As shown, an embodiment of the present application provides a handwriting erasing device 100, which includes a trigger component 110 and a strain component 120. The trigger component 110 includes a trigger portion 111 in contact with the touch screen 20, and a pressing portion 112 arranged on the inner side of the trigger portion 111; the strain component 120 includes a strain sensing component 121 arranged opposite to the pressing portion 112.

[0155] like Figure 3c-3d As shown, when in use, the pressing portion 112 presses the strain sensing component 121, and the strain sensing component 121 is deformed according to the pressing force applied by the pressing portion 112 (such as Figure 3d The state shown in FIG. 11A and generates an erasing signal corresponding to the deformation, and uses the erasing signal to erase the handwriting displayed on the touch screen 20. When the pressing portion 112 does not press the strain sensing component 121, the strain sensing component 121 returns to the initial state (as shown in FIG. 11B ). Figure 3c transition shown).

[0156] It should be noted that if Figure 3a-Figure 3b As shown, when the handwriting erasing device 100 is used to erase the image on the touch screen 20, the pressing portion 112 transmits the force exerted by the trigger portion 111 in contact with the touch screen 20 to the strain sensing component 121, and the strain sensing component 121 deforms according to the pressing force and generates an erasing signal corresponding to the deformation; when the force exerted by the trigger portion 111 in contact with the touch screen 20 changes, the deformation degree of the strain sensing component 121 also changes accordingly and generates a corresponding erasing signal; in this process, when the contact force between the trigger portion 111 and the touch screen 20 is different, the strain sensing component 121 can generate different erasing signals according to different pressing forces, and the user can achieve graded erasing of the image on the touch screen 20 by adjusting the contact force between the trigger portion 111 and the touch screen 20, thereby achieving erasing effects of different degrees, which can achieve Figure 2 The erasing effect shown is similar to that of a pencil, which is beneficial to improving the performance of the handwriting erasing device 100.

[0157] It should be understood that the erase signal is a signal representing the magnitude of the pressing force applied by the pressing portion 112 to the touch screen 20 , and may be specifically sent as voltage information in a circuit.

[0158] See also Figure 4a and Figure 4b , Figure 4a This is a schematic diagram of the structure of the strain sensing component in the embodiment of the present application; Figure 4b Schematic diagram of the structure of the strain sensing component and the pressing part in the embodiment of the present application.

[0159] like Figure 4a As shown, the strain sensing assembly 121 includes a plurality of strain sensing elements 1211 , and all the strain sensing elements 1211 are located in the same plane.

[0160] Furthermore, the strain sensing assembly 121 further includes a strain substrate 122, on which all strain sensing elements 1211 are disposed, and the strain substrate 122 is a centrosymmetric structure as a whole. It should be noted that the strain substrate 122 may also adopt other structural forms, for example, it may be a non-centrosymmetric structure.

[0161] Furthermore, the strain substrate 122 includes substrate components 1221 arranged in pairs, and the substrate components 1221 arranged in pairs are evenly arranged around the geometric center point of the strain substrate 122 .

[0162] Further Figure 4b As shown, a plane parallel to the plane where all the strain sensing elements 1211 are located is taken as a projection plane (the plane shown in A in the figure), and all the strain sensing elements 1211 are evenly distributed in an array in the projection plane. The projection of the pressing portion 112 on the projection plane (the area shown in B in the figure) is located within the outer contour of the projection of all the strain sensing elements 1211 on the projection plane.

[0163] The pressing portion 112 is configured as a protruding structure 1121 protruding from the inner side of the trigger portion 111 , the protruding direction of the protruding structure 1121 is perpendicular to the strain substrate 122 , and the projection point of the geometric center of the end of the protruding structure 1121 on the projection plane coincides with the geometric center point of the strain substrate 122 .

[0164] It should be noted that, based on the above technical solution, the pressing portion 112 can apply the squeezing force to the strain sensing component 121 regardless of the position thereof when it is subjected to the squeezing force of the trigger portion 111. This enables the strain sensing component 121 to generate a corresponding erasing signal regardless of the position of the trigger portion 111 in contact with the touch screen 20, and to perform a corresponding erasing action on the handwriting displayed on the touch screen 20.

[0165] Furthermore, since each strain sensing element 1211 can be deformed independently when subjected to force, the probability that when a certain position of the strain sensing component 121 is deformed under force, other positions are affected and deformed to generate an erroneous erasure signal can be reduced. The structure can not only ensure that the handwriting erasing device 100 has a larger sensing range, but also improve the accuracy of the handwriting erasing device 100 in performing the erasing action, which is conducive to further improving the performance of the handwriting erasing device 100.

[0166] Furthermore, the present application arranges the projection point of the geometric center of the end of the protruding structure 1121 on the projection plane to coincide with the geometric center point of the strain substrate 122, so that when the pressing portion 112 applies pressing force to the corresponding strain sensing element 1211 at different angles, the pressing force applied to the corresponding strain sensing element 1211 will not be affected by the change in the pressing angle, thereby affecting the erasing effect of the handwriting erasing device 100.

[0167] Furthermore, the present application sets all the strain sensing elements 1211 on the strain substrate 122, and the strain substrate 122 as a whole has a centrally symmetrical structure, so that multiple strain sensing elements 1211 can be arranged at various angles, so that when the trigger part 111 and the pressing part 112 squeeze the strain sensing component 121 at any angle, the corresponding strain sensing element 1211 in the strain sensing component 121 can be deformed and generate a corresponding erasure signal, and the user can perform a handwriting erasure action at any angle using the handwriting erasure device 100.

[0168] It is further explained that the number of strain sensing elements 1211 included in the strain sensing assembly 121 in the embodiment of the present application is not limited. Figure 4a As shown, in one embodiment, the strain sensing assembly 121 includes 8 strain sensing elements 1211. In other alternative embodiments, the strain sensing assembly 121 may also include 16 strain sensing elements 1211, 24 strain sensing elements 1211, etc., which may be specifically set according to actual design and use requirements.

[0169] It is further explained that the number of strain sensing elements 1211 is an even multiple of the number of substrate components 1221 ; for example, when the number of substrate components 1221 is n, the number of strain sensing elements 1211 may be 2n, 4n, or 6n.

[0170] It should be noted that the number of substrate components 1221 is not limited, for example, it can be set to 4, 6, 8, etc.

[0171] Exemplarily, when the number of substrate members 1221 is four, the number of strain sensing elements 1211 should be eight, sixteen or twenty-four.

[0172] When the number of the substrate components 1221 is 6, the number of the strain sensing elements 1211 should be 12, 24 or 36.

[0173] When the number of the substrate components 1221 is 8, the number of the strain sensing elements 1211 should be 16, 34 or 48.

[0174] It should be noted that the embodiment of the present application only shows a partial configuration example of the substrate component 1221 and the strain sensing element 1211 , and the number can also be other numbers, which is not limited in the embodiment of the present application.

[0175] The above examples are described below with reference to the accompanying drawings.

[0176] Figure 5a FIG. 1 is a schematic diagram of a top view of a first embodiment of a strained substrate provided in an embodiment of the present application; Figure 5aAs shown, the strain substrate 122 includes 5 pairs (10) of substrate components 1221 , each substrate component 1221 is provided with 2 strain sensing elements 1211 , and a total of 20 strain sensing elements 1211 are provided.

[0177] Figure 5b A schematic diagram of a top view of a second embodiment of a strain substrate provided in an embodiment of the present application; Figure 5b As shown, the strain substrate 122 includes 5 pairs (10) of substrate components 1221 , each substrate component 1221 is provided with 4 strain sensing elements 1211 , and a total of 40 strain sensing elements 1211 are provided.

[0178] Figure 5c A schematic top view of a third embodiment of a strained substrate provided in an embodiment of the present application;

[0179] like Figure 5c As shown, the strain substrate 122 includes three pairs (six) of substrate components 1221 , each substrate component 1221 is provided with four strain sensing elements 1211 , and a total of 24 strain sensing elements 1211 are provided.

[0180] Figure 5d FIG. 1 is a schematic top view of a fourth embodiment of a strained substrate provided in an embodiment of the present application; Figure 5d As shown, the strain substrate 122 includes two pairs (four) of substrate components 1221 , each substrate component 1221 is provided with two strain sensing elements 1211 , and a total of eight strain sensing elements 1211 are provided.

[0181] It should be noted that the specific structure of the strain substrate 122 is not limited, and can be made of a material with elastic deformation, for example, can be made of an elastic material such as metal, alloy or ceramic. The trigger component 110 is deformed under the pressure, and the strain substrate 122 is also deformed under the force of the trigger component 110 and has an elastic restoring force. The elastic restoring force can react to the trigger component 110, helping the trigger component 110 to return to its original position.

[0182] Furthermore, the specific type of the strain sensing element 1211 is not limited, and it can be a sensing element whose resistance changes with the applied force. It can convert physical quantities such as strain, such as pressure, tension, gravity, etc. into changes in resistance, thereby measuring these physical quantities. The strain sensing element 1211 is a sensing element that can convert strain or strain difference signals into electrical signals, and can measure static pressing force. Within the pressing force range, the signal output by the strain sensing element 1211 is proportional to the pressing force borne by the strain substrate 122. In one example, the strain sensing element 1211 can be a resistance strain gauge 1211A.

[0183] Furthermore, in some embodiments of the present application, Figure 6a A schematic diagram of the structure of a strain substrate and a resistance strain gauge provided in an embodiment of the present application; Figure 6b This is a schematic diagram of the structure of the flexible circuit board provided in the embodiment of the present application. Figure 6a As shown, the strain substrate 122 is configured as a strain steel sheet 1222, the strain sensing component 121 further includes a flexible circuit board 1223, the strain steel sheet 1222 and the flexible circuit board 1223 are stacked, and the strain sensing element is configured as a resistance strain gauge 1211A attached to a side of the flexible circuit board 1223 away from the strain steel sheet 1222. The strain steel sheet 1222 is closer to the pressing portion 112 than the flexible circuit board 1223.

[0184] Furthermore, the resistance strain gauge 1211A may also be disposed between the strain steel gauge 1222 and the flexible circuit board 1223 , or may be directly attached to the strain steel gauge 1222 , and the present application does not impose any limitation on this.

[0185] It should be noted that the specific structure of the strain steel sheet 1222 is not limited. By setting the strain steel sheet 1222, the flexible circuit board 1223 can be supported. Since the flexible circuit board 1223 is a flexible structure and the internal integrated circuit structure may be damaged after multiple squeezing, and the circuit may be affected on the other hand. This structure can effectively protect the flexible circuit board 1223 and reduce the probability of damage and failure of the flexible circuit board 1223 after multiple uses.

[0186] During use, when the strain steel sheet 1222 is subjected to impact force, the conduction loss of the impact force is small, and the conversion rate of the impact force into deformation is high. Even when the strain steel sheet 1222 is subjected to a small impact force, the resistance strain gauge 1211A can convert its deformation into an electrical signal, thereby generating an erasure signal of the handwriting erasing device 100, which is beneficial to improving the sensitivity of the strain component 120.

[0187] Furthermore, if Figure 6a and Figure 6b As shown, the flexible circuit board 1223 includes a first portion 1223A and a second portion 1223B. The first portion 1223A is stacked with the strain substrate 122 and attached to a side of the strain substrate 122 away from the pressing portion 112, and all strain sensing elements 1211 are attached to a surface of the first portion 1223A away from the strain substrate 122. The second portion 1223B bends and extends toward one side of the first portion 1223A and is located outside the strain substrate 122.

[0188] like Figure 7a As shown, Figure 7aA schematic diagram of the connection structure of the strain substrate and the auxiliary resistor provided in one embodiment of the present application. In some embodiments of the present application, a pair of resistance strain gauges 1211A are attached to each substrate member 1221, and the resistance strain gauges 1211A on each substrate member 1221 are also electrically connected to the corresponding pair of auxiliary resistors 1224 to form a Wheatstone bridge circuit.

[0189] It should be noted that by configuring each pair of resistance strain gauges 1211A to be electrically connected to a corresponding pair of auxiliary resistors 1224, each pair of auxiliary resistors 1224 may be resistors integrated in the second part 1223B of the flexible circuit board 1223, or may be arranged at other positions on the flexible circuit board 1223, or may not be arranged on the flexible circuit board 1223. It is sufficient that each pair of auxiliary resistors 1224 is electrically connected to the corresponding resistance strain gauges 1211A, and the present application does not make a unique requirement for its configuration method.

[0190] With the above configuration, each resistance strain gauge 1211A and the corresponding auxiliary resistor 1224 can form a half-bridge circuit of the Wheatstone bridge circuit, and interference between the half-bridge circuits is relatively small.

[0191] It should be further explained that the Wheatstone bridge circuit (English: Wheatstone bridge, also known as Wheatstone bridge, Wheatstone bridge) is used to accurately measure the resistance value of an unknown resistor.

[0192] Figure 7b The circuit diagram of the Wheatstone bridge circuit is as follows: Figure 7b As shown, R1, R2, R3, and Rx are the resistors on the four bridge arms, Rx is the resistor to be measured, and G is the galvanometer. The four resistors are connected to form a quadrilateral, which is called the four arms of the bridge. One diagonal of the quadrilateral is connected to the galvanometer, which is called the "bridge"; the other diagonal of the quadrilateral is connected to the DC power supply.

[0193] When the power is turned on, current flows through each branch of the bridge circuit. When the potentials of points BD are not equal, the current Ig in the bridge circuit is ≠ 0, and the pointer of the galvanometer deflects; when the potentials between points BD are equal, the current Ig in the bridge circuit is 0, and the pointer of the galvanometer points to zero (the zero point of the galvanometer is in the middle of the dial), which is the balanced state of the bridge. Using the circuit, R1, R2 and R3 are all known, so the resistance to be measured Rx can be calculated.

[0194] See also Figure 7c , Figure 7c The circuit diagram provided in this embodiment of the present application is shown in conjunction with Figure 7a and Figure 7cIt is understood that when the substrate component 1221 of the strain substrate 122 is subjected to pressure, it will be deformed, so that the resistance strain gauge 1211A arranged on the substrate component 1221 will also be deformed accordingly, causing its resistance value to change, that is, when the resistance values ​​of the resistors R1 and R3 (corresponding to the two resistance strain gauges 1211A on the same substrate component 1221) change due to the deformation of the resistance strain gauge 1211A, since each pair of auxiliary resistors 1224 is located outside the substrate component 1221 of the strain substrate 122, their resistance values ​​do not change, that is, the resistors R2 and R4 are not disturbed, and no resistance value change occurs, and can be used as reference resistors.

[0195] exist Figure 7a and Figure 7c In the example, four full-bridge circuits are designed, and a half-bridge circuit is placed in each arm (i.e., each substrate component 1221), for a total of four half-bridges; at the same time, the corresponding other four half-bridges are placed on the back-end circuit (for example, on the second part 1223B of the flexible circuit board 1223).

[0196] See also Figures 8a to 8c , Figure 8a A schematic diagram of a structure of a strain substrate provided in an embodiment of the present application, Figure 8b Another structural schematic diagram of a strain substrate provided in an embodiment of the present application is shown in FIG. Figure 8c A circuit diagram is provided in another embodiment of the present application.

[0197] like Figure 8a As shown, two pairs of resistance strain gauges 1211A are attached to each substrate member 1221 , and each two pairs of resistance strain gauges 1211A are electrically connected to form a Wheatstone bridge circuit; and the two pairs of resistance strain gauges 1211A in each Wheatstone bridge are arranged in a ring shape.

[0198] like Figure 8b As shown, two pairs of resistance strain gauges 1211A are attached to each substrate member 1221 , and each two pairs of resistance strain gauges 1211A are electrically connected to form a Wheatstone bridge circuit; and the two pairs of resistance strain gauges 1211A in each Wheatstone bridge are arranged side by side.

[0199] exist Figure 8a and Figure 8b In the example of FIG. 1 , four full-bridge circuits are designed, with one full-bridge circuit placed in each arm (ie, each substrate member 1221 ).

[0200] like Figures 8a to 8c As shown, when external force acts on the pen cap, when the resistance strain gauge 1211A changes its resistance due to deformation of the substrate component 1221, the resistance R1, R2, R3, and R4 corresponding to the resistance strain gauge 1211A on the cross bridge arm also change due to strain.

[0201] It should be noted that the resistance strain gauges 1211A are arranged in a ring or side by side, so that when the substrate component 1221 is deformed at any angle, the resistance strain gauge 1211A can change its resistance value due to the deformation of the substrate component 1221, which is beneficial to improving the sensitivity of the strain component.

[0202] It should be further explained that, in the embodiment of the present application, the number of the resistance strain gauges 1211A is not limited to two pairs, but can also be 3 pairs, 4 pairs, etc., which can be specifically set according to actual design and usage requirements.

[0203] It should be noted that the resistance strain gauge is a component used to measure strain, which can convert the change of strain on the mechanical component into the change of resistance. In this application, the specific structure of the resistance strain gauge is not limited. The structure and working principle of the resistance strain gauge provided in the embodiment of the present application are explained below in conjunction with the accompanying drawings.

[0204] See also Figures 9a to 9c , Figure 9a A schematic diagram of the structure of a resistance strain gauge provided in an embodiment of the present application, Figure 9b A schematic diagram of the structure of a resistance strain gauge provided in another embodiment of the present application is shown in FIG. Fig.9c This is a strain principle diagram of the resistance strain gauge provided in an embodiment of the present application.

[0205] like Figure 9a As shown, the resistance strain gauge 1211A is wound into a grid-shaped sensitive grid 12A by constantan wire or nickel-chromium wire with a diameter of Φ (diameter) = 0.02-0.05 mm. The sensitive grid 12A is fixed on the substrate 12B, and the constantan wire or nickel-chromium wire is connected to the external circuit through the wire 12C. The wire 12C is connected to the strain gauge wire grid using a silver-plated copper wire.

[0206] like Figure 9b As shown, the resistance strain gauge 1211A is formed by etching a very thin metal foil 12D into a grid shape and formed on a substrate 12B, and the metal foil 12D is connected to an external circuit through a wire 12C. The wire 12C is connected to the metal foil 12D using a silver-plated copper wire.

[0207] It should be noted that the resistance strain gauges of the above two structures are both sandwiched between two layers of insulating sheets after being formed into a grid shape.

[0208] Furthermore, if Fig.9cAs shown in the figure, the resistance strain gauge is based on the principle that the resistance of the material changes when it is subjected to mechanical stress. Specifically, the measurement principle of the resistance strain gauge is: the resistance value of the metal wire is related to the properties of the material as well as the length and cross-sectional area of ​​the metal wire. The metal wire is pasted on the component. When the component is deformed by force, the length and cross-sectional area of ​​the metal wire also change with the component, and then the resistance changes. The resistance change rate ΔR / R of the resistor is converted into a voltage output, which is then provided to the amplifier circuit for amplification and measurement.

[0209] dR / R=Ks*ε;

[0210] Among them, Ks is the sensitivity coefficient of the material, and its physical meaning is the resistance change rate per unit strain, which indicates whether the wire-like resistance strain gauge effect is significant or not. ε is the strain at the measuring point, which is a dimensionless quantity, but it is customary to give a unit microstrain, usually represented by the symbol με.

[0211] From this we can see that when the metal wire produces a strain effect, the strain ε is linearly related to the resistance change rate dR / R. This is the theoretical basis for using metal strain gauges to measure component strain.

[0212] Furthermore, the deformation capacity of the resistance strain gauge is related to its elastic modulus value. Specifically, the elastic modulus refers to the mathematical description of the elastic deformation (non-permanent deformation) trend of an object when an external force is applied to it. The elastic modulus can be regarded as an indicator of the ease with which a material can produce elastic deformation. The larger its value, the greater the stress required to make the material undergo a certain elastic deformation, that is, the greater the stiffness of the material, the smaller the elastic deformation under a certain stress.

[0213] It should be further explained that, in the embodiment of the present application, the following steps may be adopted when the resistance strain gauge 1211A is attached to the substrate member 1221:

[0214] Before patching, the resistance strain gauge to be used shall be inspected for appearance and resistance value shall be measured. The appearance inspection can be carried out with the naked eye or with the help of a magnifying glass. The purpose is to observe whether the sensitive grid has rust spots, defects, whether it is neatly arranged, whether the substrate and covering layer are damaged, and whether the lead is intact. Resistance measurement JM3840 quarter bridge measurement resistance. The purpose is to check whether the sensitive grid has open circuit or short circuit, and to sort the resistance value. For a group of resistance strain gauges with shared temperature compensation, the resistance value difference shall not exceed ±0.5. The resistance strain gauges measured at the same time must have the same sensitivity coefficient.

[0215] For metal components such as steel, the first step is to remove the surface paint, oxide layer and dirt; then grind or file it flat and polish it with fine sandpaper. This process is usually called "polishing". The polishing finish should be about ▽5. For very smooth components, it is necessary to use fine sandpaper to cross-grind some lines along the 45° direction to enhance the bonding force. The polishing area is about 5 times the area of ​​the resistance strain gauge. After polishing, use a scriber to gently mark the exact position of the patch. The last step of surface treatment is cleaning. That is, use clean cotton yarn or absorbent cotton balls dipped in acetone or other volatile solvents to repeatedly scrub the patch area until no dirt is seen on the cotton balls.

[0216] The patch process varies with the adhesive used. The process of patching with 502 glue is to drop a little 502 glue on the patch position after the cleaning agent evaporates, spread the glue evenly on the back of the resistance strain gauge, and then use tweezers to move the resistance strain gauge to adjust the position and angle. After positioning, place a layer of polyethylene or tetrafluoroethylene film on the resistance strain gauge, and gently squeeze out the excess glue and bubbles with your fingers. After the glue is initially cured, it can be released.

[0217] After the adhesive is initially cured, the wire can be welded. For static measurement at room temperature, a two-core multi-strand copper plastic wire can be used as the conductor, and for dynamic measurement, a three-core or four-core shielded cable can be used as the conductor. The connection between the resistance strain gauge and the conductor is through the terminal block, and the solder joints are guaranteed to be free of cold solder joints.

[0218] Observe whether the patch orientation is correct, whether the gauge is damaged, whether the paste is firm and whether there are bubbles. Measuring the resistance value can check whether there is a circuit break or loop. Insulation resistance is the most important inspection indicator. The insulation quality depends on the base of the resistance strain gauge. The resistance strain gauge with poor paste or insufficient curing often has low insulation resistance.

[0219] Finally, the dampness of the strain gauge will reduce the insulation resistance and bonding strength, and in severe cases, the sensitive grid will be corroded; the infiltration of acids, alkalis and oils will even change the physical properties of the substrate and the adhesive. In order to prevent the infiltration of free moisture, rainwater and dew in the atmosphere, and to prevent the intrusion of impurities such as acids, alkalis and oils in special environments, a protective layer is applied to the resistance strain gauge that has been fully dried, solidified and welded with wires.

[0220] The protective layer uses protective agents such as vaseline, lime, gun oil, rosin mixture, epoxy resin, etc.

[0221] It is further necessary to explain that if Figure 7a and Figure 7c As shown, the principle of generating electrical signal information by the resistance strain gauge 1211A in the embodiment of the present application when it is pressed is as follows:

[0222]

[0223] Among them, VO represents the detection voltage; VS represents the given circuit excitation voltage, which is a fixed value; GF represents the sensitivity coefficient of the relationship between the resistance change rate and the strain, which is a constant; ε1 and ε2 represent the strain in the strain area on the lower surface of a substrate component 1221 (i.e., a single arm), and ε3 and ε4 represent the strain of the reference resistor on the rear strain gauge, which should be 0. When the resistance strain gauge 1211A is deformed by force, the corresponding voltage change can be obtained according to the above formula.

[0224] It should be understood that a voltmeter can be provided in the Wheatstone circuit, and the detection voltage V detected by the voltmeter is 0 The voltmeter may be integrated into the flexible circuit board 1223 or may be disposed at other locations, which is not a sole requirement in the embodiments of the present application.

[0225] See also Fig.10 , Fig.10 FIG. 1 is a schematic diagram of the connection structure between the sensing electrode and the flexible circuit board in the embodiment of the present application. In some embodiments of the present application, for example Fig.10 As shown, in some embodiments of the present application, the handwriting erasing device 100 further includes a signal transmitting component (not shown in the figure), which is used to send an erasing signal to an electronic device using the touch screen 20.

[0226] It should be understood that the signal transmitting component can be a wireless transmitting module, such as a Bluetooth module. When the handwriting erasing device 100 performs the handwriting erasing action, the handwriting erasing device 100 establishes a connection with the electronic device using the touch screen 20 via Bluetooth, and sends an erasing signal to the electronic device using the touch screen 20 in real time via Bluetooth.

[0227] Furthermore, the handwriting erasing device 100 includes a sensing electrode 130A, the sensing electrode 130A constitutes the pressing portion 112, and the sensing electrode 130A is electrically connected to the flexible circuit board.

[0228] It should be noted that, since many conductors are arranged inside the touch screen 20, the sensing electrode 130A is used, so that the handwriting erasing device 100 in the present application can generate capacitance with the touch screen 20 when it is close to the touch screen 20. In this process, no other operation is required, and the handwriting erasing device 100 can interact with the touch screen 20 and enable the pen eraser function, which is more convenient to use.

[0229] It should be understood that the embodiment of the present application uses the sensing electrode 130A as the signal transmitting end of the strain component 120, which can also be understood as the sensing electrode 130A is a capacitive sensor signal transmitting end. The specific structure of the sensing electrode 130A is not limited, for example, the sensing electrode 130A can be a TX electrode.

[0230] When the handwriting erasing device 100 performs a handwriting erasing action, the TX electrode approaches or contacts the touch screen 20, and a capacitance change occurs between the TX electrode and the touch screen 20. The capacitance change signal can be used as a trigger signal for enabling the pen eraser function.

[0231] The use principle of the sensing electrode 130A is explained below.

[0232] Specifically, Fig.11 Figure 1 is the schematic diagram of capacitive sensing. Fig.11 As shown, capacitive sensing is a technology based on capacitive coupling. The human body is a conductor and there is capacitance between it and the sensor. When a finger approaches the sensor, the capacitance increases. Through this effect, the approaching action of the human hand can be detected. Similarly, when the handwriting erasing device uses a sensing electrode, there is a similar induction between the handwriting erasing device and the screen of the electronic device.

[0233] See also Figures 12a to 12d , Fig.12a A schematic diagram of the exploded structure of the handwriting erasing device provided in an embodiment of the present application. Figure 12b This is a schematic cross-sectional view of the handwriting erasing device provided in an embodiment of the present application. Fig.12c A schematic diagram of the top view of the handwriting erasing device provided in an embodiment of the present application. Fig.12d A schematic diagram of the structure of a strain component provided in an embodiment of the present application.

[0234] like Fig.12a and Figure 12b As shown, in some embodiments of the present application, the handwriting erasing device 100 may further include an insulating member 140, which is disposed between the sensing electrode 130A and the strain sensing component 121. The end of the sensing electrode 130A is adapted to be in a groove 141 at the corresponding end of the insulating member 140, and the end of the insulating member 140 away from the sensing electrode 130A also forms a protruding structure 142 aligned with the geometric center point of the strain substrate 122. When the triggering part 111 is subjected to force, the protruding structure 142 of the insulating member 140 presses the strain substrate 122 of the strain sensing component 121.

[0235] It should be understood that the end of the sensing electrode 130A fits into the groove 141 of the corresponding end of the insulating member 140 and can be fixed by gluing the contact surface. During assembly, a gasket can also be placed in the groove 141 to adjust the height of the sensing electrode 130A.

[0236] The sensing electrode 130A and the triggering part 111 are integrated by an in-film injection molding process or glue bonding. The sensing electrode 130A can be bonded to the inner wall of the housing 160 for fixation, and glue is poured into the gap to form a seamless structure.

[0237] The flexible circuit board 1223 is bonded to the bottom surface of the substrate member 1221, the insulating member 140 is bonded to the top of the substrate member 1221, and the end of the insulating member 140 is fixedly connected to the step surface of the bracket 123. The flexible circuit board 1223 and the sensing electrode 130A are pressed and electrically connected through the conductive foam 122A.

[0238] When in use, the coding signal on the flexible circuit board 1223 will be connected to the sensing electrode 130A through the conductive foam 122A.

[0239] It should be understood that the handwriting erasing device 100 in the embodiment of the present application may include a mainboard with an integrated processor, and the coding signal is sent by the mainboard, through the flexible circuit board 1223 and the conductive foam 122A, and finally connected to the sensing electrode 130A. Using this signal, the electronic device 30 can find the point position when the handwriting erasing device 100 slides on the touch screen 20, that is, to realize the erasing position confirmation. Here, the electrical connection scheme can also be a conductive and fixed scheme such as a spring or a conductive gel.

[0240] It is further necessary to understand that when the sensing electrode 130A performs a handwriting erasing action in the handwriting erasing device 100, the TX electrode approaches or contacts the touch screen 20, and a capacitance change occurs between the TX electrode and the touch screen 20. The capacitance change can also be used to roughly determine the erasing position and erasing range of the trigger component 110 of the handwriting erasing device 100 relative to the touch screen 20. In the embodiment of the present application, the sensing electrode 130A is connected to the flexible circuit board 1223 through the conductive foam 122A. In this way, the main board in the handwriting erasing device 100 can transmit the coding signal through the flexible circuit board 1223 and the conductive foam 122A, and finally connect to the sensing electrode 130A. In this way, the erasing position and erasing range of the trigger component 110 relative to the touch screen 20 can be determined more accurately, thereby improving the performance of the handwriting erasing device 100.

[0241] It is further understood that when the handwriting erasing device 100 is applied to an electronic stylus, the main board can be the refill main board of the electronic stylus, and the coding signal on the flexible circuit board 1223 will be connected to the sensing electrode 130A through the conductive foam 122A; the coding signal is sent by the refill main board, passes through the flexible circuit board 1223 and the conductive foam 122A, and finally connects to the sensing electrode 130A. Using this signal, the electronic device can find the point position when the handwriting erasing device slides on the screen, that is, to confirm the erasing position and erasing range.

[0242] like Figure 12c-12dAs shown, the handwriting erasing device 100 also includes a bracket 123, which has a hollow area or a sunken area. One end of a plurality of substrate components 1221 away from the geometric center point is fixed to the bracket 123, and the other ends are interconnected and suspended in the hollow area or the sunken area of ​​the bracket 123 to form an end-fixed beam structure.

[0243] This structure allows the peripheral ends of the substrate member 1221 to be fixed, and the middle portion will deform after receiving the pressure transmitted in. The resistance strain gauge disposed on the substrate member 1221 can convert the corresponding tiny deformation into an electrical signal.

[0244] It should be noted that when the trigger component 110 is subjected to pressure (which can be understood as the reaction force applied to the trigger component 110 by the touch screen 20), the trigger component 110 is deformed, and the trigger component 110 sequentially transmits the pressure to each substrate member 1221 of the strain substrate 122. Since the other end of each substrate member 1221 (i.e., the end of each substrate member 1221 connected to the trigger component 110) is suspended in the air, a large deformation can be generated in the axial direction of the pen cap. The deformation generated by each substrate member 1221 is large, so that the deformation can be better transmitted to the strain sensing element 1211, so that the sensitivity of the strain sensing component 121 is higher.

[0245] See also Fig.12e , Fig.12e This is a schematic diagram of the isometric structure of the handwriting removal device provided in the embodiment of the present application. In some embodiments, Fig.12a and Fig.12e As shown, the outer surface of the trigger portion 111 may have a soft protective layer 150 to protect the trigger portion 111 .

[0246] Further, continue to combine Fig.12e It is understood that the handwriting erasing device 100 may further include a housing 160 , the trigger component 110 and the strain component 120 are fixed in the housing 160 , and the trigger portion 111 is partially exposed from the housing 160 .

[0247] See also Fig.12f , Fig.12f This is a diagram of the use status of the handwriting erasing device provided in the embodiment of the present application. Fig.12f As shown, when the handwriting erasing device in the embodiment of the present application performs a handwriting erasing action, the reaction force F applied by the touch screen 20 is only transmitted to the corresponding substrate component 1221 through the triggering portion 111, the pressing portion 112, and the insulating member 140 in sequence.

[0248] Further, Fig.13 This is a partial cross-sectional structural diagram of the handwriting erasing device provided in the embodiment of the present application. Fig.13As shown, in some embodiments of the present application, the portion of the trigger portion 111 exposed from the housing 160 is in a truncated spherical structure, and a cross-sectional center angle G of the truncated spherical structure is in a range of 90° to 150°.

[0249] It should be noted that by configuring the trigger portion 111 to be a truncated spherical structure, and the cross-sectional center angle G of the truncated spherical structure is within the range of 90° to 150°, the handwriting erasing device 100 in the present application can have a larger erasing range.

[0250] It should be further explained that, in the embodiment of the present application, the cross-sectional center angle G of the truncated spherical structure can be set to any angle in the range of 90° to 150°, for example, the cross-sectional center angle G of the truncated spherical structure can be set to 90°, 125°, 150°, etc.

[0251] See also Fig.14a and Fig.14b , Fig.14a This is a schematic diagram of the assembly structure of the pen cap provided in an embodiment of the present application. Fig.14b This is a schematic diagram of the cross-sectional structure of the pen cap provided in an embodiment of the present application.

[0252] See also Fig.14a and Fig.14b The present application also provides a pen cap for an electronic stylus, the pen cap 10C is arranged at the end of the electronic stylus 10, and is used to perform the eraser function of the electronic stylus; the pen cap 10C includes the handwriting erasing device 100 of the above-mentioned structural touch screen 20.

[0253] It should be noted that, by integrating the handwriting erasing device 100 of the above structure into the pen cap of the electronic stylus, when realizing the handwriting erasing function, the handwriting erasing device 100 of the above structure can not only realize different degrees of erasing effects based on the size of the pressing force, but also realize multi-angle recognition and erasing. The pen cap of the electronic stylus adopts this structure, which can not only enhance the functional diversification of the electronic stylus pen cap, but also enhance the performance of the electronic stylus.

[0254] It should be further explained that, since the pen cap is integrated with the handwriting erasing device 100 of the above structure, the user can achieve different degrees of erasing effects by applying different amounts of pressing pressure to the pen cap.

[0255] See also Fig.15a and Fig.15b , Fig.15a This is a schematic diagram of the assembly structure of the electronic stylus provided in the embodiment of the present application. Fig.15b This is a schematic cross-sectional structural diagram of the electronic stylus provided in an embodiment of the present application.

[0256] like Figure 15a-Figure 15bAs shown, the present application also provides an electronic stylus pen 10, which includes a pen body 10B and a pen head 10A arranged at one end of the pen body, and further includes a pen cap 10C of the above structure.

[0257] The pen cap 10C provided in the embodiment of the present application is not limited to being used in conjunction with an electronic stylus. When the pen cap 10C is used in conjunction with an electronic stylus, the shell of the electronic stylus can serve as the shell of the pen cap 10C.

[0258] Furthermore, the pen cap 10C can also be used as a separate product, which can be plugged and connected to the end of the pen body 10B.

[0259] It should be noted that, since the pen cap of the above structure can realize different degrees and multi-angle recognition based on the size of the pressing force to eliminate the handwriting on the touch screen 20, the performance of the electronic stylus can be improved.

[0260] When the user draws an erroneous audio-visual image due to some unexpected circumstances such as accidental touch, in this case, a handwriting erasing device is needed to erase the erroneous audio-visual image. The electronic stylus pen 10 can be turned 180 degrees so that the cap 10C of the electronic stylus pen 10 is in contact with the touch screen, and the erroneous audio-visual image can be erased using the cap 10C. In this process, the user can achieve different degrees of erasing effects by applying different amounts of pressing force to the cap.

[0261] It should be further explained that, by plugging and unplugging the pen cap to the other end of the pen barrel, the pen cap can be used independently when the handwriting erasing function is used, which is more convenient to use.

[0262] Specifically, a flange structure may be provided inside the shell of the pen cap 10A, and a groove structure matching the flange structure may be provided at the tail of the pen body 10B. The pen cap 10A may be pluggably connected to the other end of the pen body 10B by using the flange and the groove.

[0263] See also Figures 16a to 16d , Fig.16a This is a principle block diagram of a handwriting removal method provided in one embodiment of the present application. Figure 16a' Another principle block diagram of a handwriting removal method provided in an embodiment of the present application. Fig.16b The present invention provides a method for removing handwriting. Fig.16c A schematic diagram of a scene of a handwriting removal method provided in an embodiment of the present application. Fig.16d A schematic diagram of another scenario of the handwriting removal method provided in an embodiment of the present application.

[0264] like Figure 16a to Figure 16bAs shown, the embodiment of the present application also provides a method for erasing handwriting on a touch screen, using the electronic stylus or the pen cap of the electronic stylus with the above structure to perform the pen erasing function. The method for erasing handwriting on a touch screen includes:

[0265] The triggering unit 111 of the handwriting erasing device 100 receives a feedback signal from the electronic device 30 using a touch screen to trigger the eraser function of the pen cap.

[0266] Detect and send electrical signal information indicating that the trigger part 111 is subjected to force.

[0267] The target pressure information of the pen cap is determined according to the electrical signal information, and the target pressure information is sent to the electronic device 30 (ie, the target electronic device), so that the electronic device 30 determines the degree of erasure of the handwriting displayed on the touch screen 20 according to the target pressure information. Specifically, the target pressure information includes the pressure size information of the pen cap.

[0268] For example, Fig.16c As shown, when the cap 10C of the electronic stylus 10 presses the touch screen 20, the feedback signal can be understood as the reaction force applied by the touch screen 20 to the trigger part 111. The pressure magnitude information is the magnitude of the reaction force.

[0269] When the trigger portion 111 is squeezed by the reaction force, in one embodiment, Figure 3b As shown, the reaction force is directly transmitted to the strain sensing component 121 through the trigger part 111 and the pressing part 112 in sequence. At this time, the strain sensing component 121 detects the reaction force and generates corresponding electrical signal information, which can be voltage information representing the magnitude of the reaction force.

[0270] Specifically, in this embodiment, the strain sensing component 121 may be as follows: Figure 7a In the structure shown, the strain sensing component 121 includes a strain substrate 122 (for example, a strain steel sheet 1222), a flexible circuit board 1223 attached to the side of the strain substrate 122 away from the pressing portion 112, and a plurality of strain sensing elements (for example, a plurality of resistance strain gauges 1211A) attached to the surface of the first part of the flexible circuit board 1223. Each pair of resistance strain gauges 1211A on each substrate member 1221 and a corresponding pair of auxiliary resistors 1224 form a Wheatstone circuit. When the reaction force applied by the touch screen 20 to the trigger portion 111 is transmitted to the strain sensing component 121, the strain steel sheet 1222 is squeezed and deformed, and the resistance value of the resistance strain gauge 1211A attached to the surface of the strain steel sheet 1222 through the flexible circuit board 1223 changes with the deformation of the strain steel sheet 1222, so that the resistance strain gauge 1211A and the auxiliary resistor 1224 form a Wheatstone circuit to output corresponding voltage information, and the voltage information can be used to characterize the magnitude of the reaction force.

[0271] It can also be Figure 8a-8b In the structure shown, two pairs of resistance strain gauges 1211A on each substrate component 1221 are connected to each other to form a Wheatstone circuit. When the reaction force applied by the touch screen 20 to the trigger part 111 is transmitted to the strain sensing component 121, the strain steel sheet 1222 is squeezed and deformed, and the resistance value of the resistance strain gauge 1211A attached to the surface of the strain steel sheet 1222 through the flexible circuit board 1223 changes with the deformation of the strain steel sheet 1222, so that the two pairs of resistance strain gauges 1211A constitute the Wheatstone circuit to output corresponding voltage information, and the voltage information can be used to characterize the magnitude of the reaction force.

[0272] In this embodiment, the strain sensing component 121 can be a pressure sensor that directly detects the pressing force. The pressure sensor can be a common micro pressure sensor in the art, and its model can be selected according to actual design and use requirements, and this application does not make a sole requirement.

[0273] In another embodiment, Fig.12f The reaction force is transmitted to the strain sensing component 121 through the trigger part 111, the pressing part 112, and the insulating part 140 in sequence. At this time, the strain sensing component 121 detects the reaction force and generates corresponding electrical signal information, which can be voltage information representing the magnitude of the reaction force.

[0274] When the handwriting erasing method of the present application is used to perform the handwriting erasing action, such as Fig.16a and Fig.16c As shown, the electronic stylus pen 10 may be rotated 180° so that the cap 10C of the electronic stylus pen 10 contacts and moves relatively with the touch screen 20 , and then the handwriting erasing action is performed.

[0275] In this embodiment, the electronic stylus 10 may have a processor 10D. The processor 10D may include storage and processing circuits for supporting the operation of the electronic stylus 10. The storage and processing circuits may include storage devices such as non-volatile memory (e.g., flash memory or other electrically programmable read-only memory configured as a solid-state drive), volatile memory (e.g., static or dynamic random access memory), etc. The processing circuit in the processor 10D may be used to control the operation of the electronic stylus 10. The processing circuit may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, application-specific integrated circuits, etc.

[0276] The processor 10D may be used to run software on the electronic stylus 10 that controls the operation of the electronic stylus 10. During the operation of the electronic stylus 10, the software running on the processor 10D may process sensor inputs, button inputs, and inputs from other devices to monitor the movement of the electronic stylus 10 and other user inputs. The software running on the processor 10D may detect user commands and may communicate with the electronic device 30.

[0277] In order to support wireless communication between the electronic stylus 10 and the electronic device 30, the electronic stylus 10 may include a wireless module 10E. The wireless module 10E may be a type of signal transmitting component, the wireless module 10E may be a Bluetooth module, the wireless module 10E may also be a WI-FI hotspot module, a WI-FI point-to-point module, etc. The Bluetooth module may include a radio frequency transceiver, such as a transceiver. The Bluetooth module may also include one or more antennas. The transceiver may use an antenna to transmit and / or receive wireless signals, and the wireless signals may be Bluetooth signals, wireless local area network signals, long-range signals such as cellular phone signals, near field communication signals, or other wireless signals based on the type of wireless module. The electronic stylus 10 may also include a charging module, which may support the charging of the electronic stylus 10 and provide power for the electronic stylus 10.

[0278] The strain sensing component 121 in the present application is connected to the processor 10D in communication, which may be wired or wireless. When the strain sensing component 121 outputs voltage information representing target pressure information, the processor 10D obtains the target pressure information and sends the corresponding target pressure information to the electronic device 30 via the wireless module 10E.

[0279] The electronic device 30 may further include a wireless interface 30C to facilitate electronic communication between the electronic device 30 and the electronic stylus 10. The wireless interface 30C of the electronic device 30 receives the target pressure information. In one embodiment, the electronic device 30 may be configured to communicate with the electronic stylus 10 via a low-energy Bluetooth communication interface or a near-field communication interface. In other examples, the communication interface facilitates electronic communication between the electronic device 30 and an external communication network, device, or platform.

[0280] The wireless interface 30C (whether it is a communication interface between the electronic device 30 and the electronic stylus 10 or another communication interface) can be implemented as one or more wireless interfaces, Bluetooth interfaces, near-field communication interfaces, magnetic interfaces, universal serial bus interfaces, inductive interfaces, resonant interfaces, capacitive coupling interfaces, Wi-Fi interfaces, TCP / IP interfaces, network communication interfaces, optical interfaces, acoustic interfaces or any traditional communication interfaces.

[0281] The electronic device 30 further includes a processor 30A, an erasing module 30B and a display 30D (for example, a touch screen 20 may be used). The processor 30A is respectively connected to the erasing module 30B and the wireless interface 30C for communication, obtains the target pressure information, and controls the erasing module 30B to perform corresponding handwriting erasure according to the target pressure information, and controls the display 30D to display an erasing effect interface with which the user can interact.

[0282] like Figure 16a' and Fig.16d As shown, the pen cap 10C can also be used as a product independent of the electronic stylus to perform a handwriting erasing action, and the handwriting erasing is achieved by making the pen cap 10C contact and move relatively with the touch screen 20.

[0283] In this embodiment, the pen cap 10C may have a processor 101D that is independent of the processor 10D of the electronic stylus 10. The processor 101D may include storage and processing circuits for supporting the operation of the pen cap 10C. The storage and processing circuits may include storage devices such as non-volatile memories (e.g., flash memory or other electrically programmable read-only memories configured as solid-state drives), volatile memories (e.g., static or dynamic random access memories), etc. The processing circuit in the processor 101D may be used to control operations related to the pen cap 10C. The processor 101D may be integrated with the strain sensing component 121, or may be disposed at other locations of the pen cap 10C. The processing circuit may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, application-specific integrated circuits, etc.

[0284] The processor 101D can be used to run software on the pen cap 10C that controls the operation of the pen cap 10C. During the operation of the pen cap 10C, the software running on the processor 101D can process sensor inputs, button inputs, and inputs from other devices to monitor the movement of the pen cap 10C and other user inputs. The software running on the processor 101D can detect user commands and can communicate with the electronic device 30.

[0285] In order to support wireless communication between the pen cap 10C and the electronic device 30, the pen cap 10C may include a wireless module 101E. The wireless module 101E may be a type of signal transmitting component, and the wireless module 101 may be a Bluetooth module, or a WI-FI hotspot module, a WI-FI point-to-point module, etc. The Bluetooth module may include a radio frequency transceiver, such as a transceiver. The specific form of the Bluetooth module may be as described above, and will not be described in detail here.

[0286] The strain sensing component 121 in the present application is connected to the processor 101D in a communication manner, which may be a wired communication connection or a wireless communication connection. When the strain sensing component 121 outputs voltage information representing target pressure information, the processor 10D obtains the target pressure information and sends the corresponding target pressure information to the electronic device 30 via the wireless module 101E.

[0287] The wireless interface 30C of the electronic device 30 may be a communication interface between the electronic device 30 and the pen cap 10C, or may be another communication interface.

[0288] It should be noted that in the above embodiments, the handwriting erasing method can determine the degree of erasure of the handwriting displayed on the touch screen based on the pressure information of the pen cap. When the handwriting erasing function is performed using the pen cap, different erasing effects can be achieved under different erasing force sizes.

[0289] In some embodiments, the strain sensing component 121 includes a strain substrate 122 and multiple strain sensing elements 1211, and all the strain sensing elements 1211 are arranged on the strain substrate 122; the multiple strain sensing elements 1211 generate multiple electrical signal information according to the pressing force applied by the pressing portion 112, and determine the target pressure information of the pen cap according to the multiple electrical signal information, and send the target pressure information to the electronic device 30, so that the electronic device 30 determines the degree of erasure according to the target pressure information.

[0290] It should be noted that the target pressure information of the pen cap is determined by using multiple electrical signal information, so that the accuracy of the target pressure information can be guaranteed. Even if an error occurs in a certain electrical signal information, the method can reduce the degree of influence on the target pressure information.

[0291] See also Figure 17a-Figure 17c , Fig.17a Schematic diagram of a bridge circuit in an embodiment of the present application. Fig.17b This is a diagram of the pen cap model in an embodiment of the present application. Fig.17c Schematic diagram of force analysis of a certain point of the pen cap in the embodiment of the present application. Fig.17a and Fig.17b As shown, the multiple strain sensing elements 1211 correspond to N Wheatstone bridge circuits, each Wheatstone bridge circuit outputs a bridge voltage, and the multiple electrical signal information is the N bridge voltages output by the N Wheatstone bridge circuits.

[0292] Determining the pressure of the pen cap based on multiple electrical signal information includes:

[0293] The current angle information of the pen cap (which can be understood as θ in Formula 4) is determined according to the N bridge voltages. The current angle information is the angle between the direction of the reaction force applied by the touch screen 20 to the trigger part 111 and the axial direction of the pen cap.

[0294] Determine the current voltage information (which can be understood as Vmax in Formula 5) according to the N bridge voltages and the current angle information;

[0295] The pressure magnitude information (which can be understood as F in Formula 5) is determined based on the current voltage information and the calibration information; wherein the calibration information represents the one-to-one correspondence between different voltage information and different pressure information when the pen cap is subjected to force at a calibration angle (which can be understood as the relationship between Vmax and F); the calibration angle is configured as: the angle when the force direction of the pen cap coincides with the axis of the pen cap.

[0296] It should be noted that the current angle information of the pen cap is determined according to the N bridge voltages, the current voltage information is determined using the N bridge voltages and the current angle information, and the pressure information is determined according to the current voltage information and the calibration information. In this way, the erasing effect can be compensated according to the different inclination angles of the pen cap (or it can be understood that the role of calculating the inclination angle is to provide compensation for the algorithm), avoiding the need to use a larger erasing force due to the weak signal at the edge of the pen cap, so that a consistent erasing effect can be produced at different inclination angles under the same pressing force. This is also conducive to improving the accuracy of executing the handwriting erasing action on the touch screen. Or it can be understood that even when the erasing action is performed at an angle inclined relative to the axis of the pen cap, the target pressure information can more accurately characterize the actual pressing force.

[0297] It should be understood that in the present application, the processor is preset with a mathematical model. When the erasing action is performed, when the force direction of the trigger part 111 is inclined relative to the axis of the pen cap, the processor uses the mathematical model to compensate the detection value to obtain more accurate target pressure information, thereby achieving an erasing effect that matches the pressing force.

[0298] The following is an explanation of how the mathematical model is constructed:

[0299] like Fig.17c As shown in the figure, when the pen cap is used to perform an erasing action, a certain point of the pen cap is subjected to a force F, which can be decomposed into F xy and F z , the angle θ between the force F and the pen cap axial time can be calculated by the following formula 1,

[0300] Formula 1:

[0301] F xy is the horizontal component of F, F z is the vertical component of F. By matching the forces in each direction with the electrical signal, we can get Formula 2 and Formula 3:

[0302] Formula 2:

[0303] V 2i-1 and V 2i They respectively represent the current bridge voltage output by two Wheatstone bridge circuits set relatively, for example Fig.17a The V 1 and V 3 、V 2 and V 4 , K 2 is the correction coefficient, we know that the horizontal force F xy Positively correlated to the root of the sum of the squares of the differences in signal quantities between the bridge arms.

[0304] Formula 3:

[0305] V i Representing the bridge voltage of the corresponding bridge, we can know the vertical force F z Positively correlated to the sum of the signal quantities between each bridge arm.

[0306] 1≤i≤N;K 1 is the correction factor.

[0307] According to the above formula 2 and formula 3, formula 4 can be obtained:

[0308] Formula 4:

[0309] It can be seen that the angle θ between the current force direction of the pen cap and the axis of the pen cap can be calculated by the above formula 4:

[0310] Where θ represents the angle between the current force direction of the pen cap and the axis of the pen cap; 1≤i≤N; K is K 2 and K 1 The ratio of is a constant.

[0311] Therefore, the pressure F corresponding to the target pressure information can be calculated by formula 5:

[0312] Formula 5:

[0313] Furthermore, the specific selection of the embodiments of the present application Fig.17b In the five positions shown, the difference between two adjacent load angles is 15°. The angle is estimated according to the above formula with the load voltage Vs being 2.8V. See the table below for details:

[0314]

[0315] According to the above table:

[0316] When the load angle is 0° (corresponding to position 1), V1 is 456.61uV, V2 is 454.85uV, V3 is 454.14uV, V4 is 454.28uV, and the correction coefficient K is 3.5, so the estimated angle is 0.2°.

[0317] When the load angle is 15° (corresponding to position 2), V1 is 456.61uV, V2 is 433.63uV, V3 is 373.04uV, V4 is 501.85uV, the correction coefficient K is 3.5, the load voltage Vs is 2.8V, the estimated angle is 14.5°, and the deviation reaches 3.6%.

[0318] When the load angle is 30° (corresponding to position 3), V1 is 399.47uV, V2 is 379.72uV, V3 is 263.40uV, V4 is 512.06uV, the correction coefficient K is 3.5, the load voltage Vs is 2.8V, the estimated angle is 29.3°, and the deviation reaches 2.3%.

[0319] When the load angle is 45° (corresponding to position 4), V1 is 317.05uV, V2 is 290.07uV, V3 is 125.86uV, V4 is 477.63uV, the correction coefficient K is 3.5, the load voltage Vs is 2.8V, the estimated angle is 45.6°, and the deviation reaches 1.2%.

[0320] When the load angle is 60° (corresponding to position 5), V1 is 136.83uV, V2 is 106.04uV, V3 is 87.39uV, V4 is 327.55uV, the correction coefficient K is 3.5, the load voltage Vs is 2.8V, the estimated angle is 65.7°, and the deviation reaches 8.7%.

[0321] From the above analysis, it can be seen that the embodiment of the present application is more accurate based on the current angle information obtained and can compensate for the deviation angle.

[0322] In some embodiments, before receiving a feedback signal from an electronic device triggering a pen eraser function, the method further includes: sending a trigger signal for enabling the pen eraser function.

[0323] In one example, the handwriting erasing device 100 is provided with a sensing electrode 130A. When the handwriting erasing device 100 performs a handwriting erasing action, a capacitance change occurs between the sensing electrode 130A of the handwriting erasing device 100 and the touch screen 20. The capacitance change signal can be used as a trigger signal for enabling the pen eraser function.

[0324] It should be noted that the processor can transmit the coding signal through the flexible circuit board 1223 and the conductive foam 122A, and finally electrically conduct it to the sensing electrode 130A, so as to determine the erasing position and erasing range of the trigger component 110 relative to the touch screen 20.

[0325] In the above examples, those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with some embodiments, this does not mean that the features of this application are limited to the implementation methods. On the contrary, the purpose of introducing the application in conjunction with the implementation methods is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide a deep understanding of the present application, many specific details will be included in the following description. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0326] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0327] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the 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 limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0328] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0329] In the description of this application, it should be understood that in this application, "electrical connection" can be understood as physical contact and electrical conduction between components; it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals. "Communication connection" can refer to electrical signal transmission, including wireless communication connection and wired communication connection. Wireless communication connection does not require a physical medium and does not belong to a connection relationship that limits the product structure.

[0330] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A handwriting erasing device for a touch screen, characterized in that: The handwriting elimination device comprises: A trigger component, the trigger component comprising a trigger portion in contact with the touch screen, and a pressing portion disposed inside the trigger portion; A strain component, the strain component comprising a strain sensing component arranged opposite to the pressing portion; Among them, the trigger part is in contact with the touch screen and is subjected to force and presses the strain sensing component through the pressing part. The strain sensing component deforms according to the pressing force applied by the pressing part and generates an erasing signal corresponding to the deformation. The erasing signal is used to eliminate the handwriting displayed on the touch screen.

2. The handwriting erasing device for a touch screen as claimed in claim 1, characterized in that: The strain sensing component comprises a strain substrate and a plurality of strain sensing elements, wherein the plurality of strain sensing elements are arranged on the strain substrate; wherein, The multiple strain sensing elements are located in the same plane, a plane parallel to the plane where the multiple strain sensing elements are located is used as a projection plane, and the multiple strain sensing elements are distributed in a uniform array in the projection plane; and The projection of the pressing portion on the projection surface is located within the projection outer contours of the plurality of strain sensing elements on the projection surface.

3. The handwriting erasing device for a touch screen as claimed in claim 2, characterized in that: The strain substrate has a central symmetrical structure as a whole; and The pressing portion is configured as a protruding structure protruding from the inner side of the trigger portion, the protruding direction of the protruding structure is perpendicular to the strain substrate, and the projection point of the geometric center of the end of the protruding structure on the projection surface coincides with the geometric center point of the strain substrate.

4. The handwriting erasing device for a touch screen as claimed in claim 2 or 3, characterized in that: The strain substrate comprises a plurality of substrate components arranged in pairs, and the plurality of substrate components are evenly arranged around a geometric center point of the strain substrate; Every two strain sensing elements among the plurality of strain sensing elements constitute a pair of strain sensing elements, wherein at least one pair of the strain sensing elements is attached to each substrate member among the plurality of substrate members.

5. The handwriting erasing device for a touch screen as claimed in claim 4, characterized in that: Each of the multiple strain sensing elements is configured as a resistance strain gauge, a pair of the resistance strain gauges is attached to each of the multiple substrate components, and the pair of resistance strain gauges on each substrate component is electrically connected to a corresponding pair of auxiliary resistors to form a Wheatstone bridge circuit.

6. The device for erasing handwriting on a touch screen as claimed in claim 4, characterized in that: Each of the plurality of strain sensing elements is configured as a resistance strain gauge, and each of the plurality of substrate components is provided with two pairs of the resistance strain gauges, and the two pairs of the resistance strain gauges are electrically connected to form a Wheatstone bridge circuit; and The two pairs of resistance strain gauges in each Wheatstone bridge are arranged in a ring shape or side by side.

7. The handwriting erasing device for a touch screen according to any one of claims 2 to 6, characterized in that: The strain substrate is configured as a strain steel sheet.

8. The handwriting erasing device for a touch screen according to any one of claims 2 to 7, characterized in that: The strain sensing component also includes a flexible circuit board, which includes a first part and a second part. The first part is stacked with the strain substrate and attached to a side of the strain substrate away from the pressing portion. Each of the plurality of strain sensing elements is attached to a surface of the first part away from the strain substrate, so that the plurality of strain sensing elements are arranged on the strain substrate through the first part of the flexible circuit board, and the second part is bent and extended toward one side of the first part and is located outside the strain substrate.

9. The device for erasing handwriting on a touch screen as claimed in claim 8, characterized in that: When the handwriting erasing device is formed with a Wheatstone bridge circuit, the auxiliary resistor of the Wheatstone bridge circuit is arranged on the second portion of the flexible circuit board.

10. The handwriting erasing device for a touch screen according to any one of claims 1 to 9, characterized in that: The handwriting erasing device further comprises a signal transmitting component, and the signal transmitting component is used to send the erasing signal to the electronic device using the touch screen.

11. The handwriting erasing device for a touch screen according to any one of claims 1 to 10, characterized in that: The handwriting erasing device further comprises a sensing electrode, the sensing electrode constitutes the pressing portion, and when the handwriting erasing device comprises a flexible circuit board, the sensing electrode is electrically connected to the second part of the flexible circuit board.

12. The device for erasing handwriting on a touch screen as claimed in claim 11, characterized in that: The handwriting erasing device also includes an insulating member, which is arranged between the sensing electrode and the strain sensing component. The end of the sensing electrode is adapted to be fitted into a groove at the corresponding end of the insulating member, and one end of the insulating member away from the sensing electrode also forms a protruding structure aligned with the geometric center point of the strain substrate of the strain sensing component. When the triggering part is subjected to force, the protruding structure of the insulating member presses the strain substrate.

13. The handwriting erasing device for a touch screen according to any one of claims 4 to 6, characterized in that: The strain component also includes a bracket, which has a hollow area or a sinking area. One end of each of the multiple substrate components away from the geometric center point is fixed to the bracket, and the other end is connected to each other and suspended in the hollow area or the sinking area of ​​the bracket to form an end-fixed beam structure.

14. The device for erasing handwriting on a touch screen according to any one of claims 1 to 13, characterized in that: The outer surface of the trigger part is provided with a soft protective layer.

15. The device for erasing handwriting on a touch screen according to any one of claims 1 to 14, characterized in that: The handwriting erasing device further comprises a housing, the trigger component and the strain component are fixed in the housing, and the trigger part is partially exposed from the housing.

16. The device for erasing handwriting on a touch screen as claimed in claim 15, characterized in that: The portion of the trigger part exposed from the housing is in a spherical segment structure, and a cross-sectional center angle of the spherical segment structure is in a range of 90° to 150°.

17. A pen cap of an electronic stylus pen, the pen cap being arranged at the end of the electronic stylus pen and being used to perform the eraser function of the electronic stylus pen; characterized in that: The pen cap includes the handwriting erasing device for a touch screen according to any one of claims 1 to 16.

18. An electronic stylus pen, comprising a pen holder and a pen head arranged at one end of the pen holder, characterized in that: It also includes the pen cap as described in claim 17, and the pen cap is pluggable and connected to the other end of the pen barrel.

19. A method for erasing handwriting on a touch screen, characterized in that: The pen cap of the electronic stylus according to claim 17 or the electronic stylus according to claim 18 is used to perform the pen erasing function, and the method for erasing handwriting on the touch screen comprises: Receiving a feedback signal from an electronic device using the touch screen to trigger a pen eraser function of the pen cap; Detecting and sending electrical signal information indicating the force applied to the triggering portion; The target pressure information of the pen cap is determined according to the electrical signal information, and the target pressure information is sent to the electronic device, so that the electronic device determines the degree of erasure of the handwriting displayed on the touch screen according to the target pressure information; wherein the target pressure information includes the pressure size information of the pen cap.

20. The method for erasing handwriting on a touch screen as claimed in claim 19, characterized in that: The strain sensing component comprises a strain substrate and a plurality of strain sensing elements, wherein the plurality of strain sensing elements are arranged on the strain substrate; The multiple strain sensing elements generate multiple electrical signal information according to the pressing force applied by the pressing part, determine the target pressure information of the pen cap according to the multiple electrical signal information, and send the target pressure information to the electronic device, so that the electronic device determines the erasure degree according to the target pressure information.

21. The method for erasing handwriting on a touch screen as claimed in claim 20, characterized in that: The multiple strain sensing elements correspond to N Wheatstone bridge circuits, each Wheatstone bridge circuit outputs a bridge voltage, and the multiple electrical signal information is the N bridge voltages output by the N Wheatstone bridge circuits.

22. The method for erasing handwriting on a touch screen as claimed in claim 21, characterized in that: Determining the pressure information of the pen cap according to the plurality of electrical signal information includes: Determine the current angle information of the pen cap according to the N bridge voltages; the current angle information is calculated according to the following formula; Wherein, θ represents the angle between the current force direction of the pen cap and the axis of the pen cap; V 2i-1 and V 2i They respectively represent the current bridge voltage output by two Wheatstone bridge circuits set relatively, 1≤i≤N; K is the correction coefficient; Determine current voltage information according to the N bridge voltages and the current angle information; The pressure magnitude information is determined according to the current voltage information and the calibration information; wherein the calibration information represents a one-to-one correspondence between different voltage information and different pressure information when the pen cap is subjected to force at a calibration angle; the calibration angle is configured as: the angle when the force direction of the pen cap coincides with the axis of the pen cap.

23. The method for erasing handwriting on a touch screen according to any one of claims 19 to 22, characterized in that: Before receiving the feedback signal of the electronic device triggering the pen eraser function, the method further includes: Sends a trigger signal to enable the eraser function.

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