Pressure-Sensitivity and Click-Fusion Sensing System and Method for a Capacitive Stylus

Abstract

The present invention relates to the technical field of capacitive stylus pens, and provides a pressure sensing - click fusion sensing system and method for a capacitive stylus pen. The fusion sensing method includes: detecting a holding behavior based on a comparison between a detected holding capacitance value and a calibrated holding detection threshold. When the holding behavior is detected, detecting the tip pressure stress and the click trigger detection of the pen body are started. Through the tip pressure stress detection, the tip stress corresponding to the plate spacing is obtained; through the click trigger detection, it is determined that the user has a multi - click touch behavior, and a response signal is output. The present invention adopts a single - chip implementation solution, only requires a multi - channel capacitance measurement chip, and simultaneously realizes the above two or more functions; at the same time, in the design of the present invention, the assembly difficulty of parts is low, the assembly accuracy and reliability are improved, space is saved, and the BOM cost is controllable.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitive styluses, and more particularly to a pressure-sensitive - click fusion sensing system and method for a capacitive stylus. Background Art

[0002] The stylus is one of the most suitable input methods for capacitive screens and also one of the input methods that best conforms to the writing logic of humans. Currently, for commonly used stylus products, if they do not have the pressure - sensing grading function of the nib part, they cannot sense the pressing force when the user writes and then output different handwriting styles, and can only achieve point - touch and basic writing effects.

[0003] For a few stylus products with pressure - sensing grading functions, based on the strain effect of a strain - resistance body made of metal or semiconductor, through a stress - transfer structure configured inside the stylus body, the piezoresistive strain gauge is pressed and deformed during the use of the stylus, and by detecting the change in the resistance value of the piezoresistive strain gauge, and then sampling and converting through a high - resolution analog - to - digital converter (ADC), handwriting styles with, for example, 4096 gradings are output.

[0004] The stress - transfer structure of the resistance - strain type scheme adopted in the prior art has a relatively complex structure design. For example, for the pressure - sensing component and stylus disclosed in the patent application with publication number CN114201063A, a shrapnel, a main shaft, a bracket, and a strain - type sensor are provided. The main shaft is rigidly connected to the nib and passes through the bracket to abut against the abutting body position of the shrapnel, and the strain - type sensor is attached to the attaching body position of the shrapnel. The abutting body position and the attaching body position are spaced apart and connected by an intermediate connecting body. Thus, when the nib is pressed by the screen, the main shaft will move, thereby pushing the abutting body to move away from the attaching body. Since the attaching body and the bracket are relatively fixed, the attaching body will deform at this time, and the output signal of the strain - type sensor will change with the different deformation amounts of the attaching body, thereby realizing the detection of the writing pressure. It should be noted that in the nib pressure - sensing design using the resistance - strain type method, a basic prerequisite for applying the piezoresistive strain gauge for stress measurement is the existence of an elastic body (such as the attaching body in the shrapnel used in the aforementioned CN114201063A), that is, encapsulating the piezoresistive strain gauge on a rigid structure made of special materials and structures, so that it can fully recover after strain occurs. In other words, in the nib structure of the stylus, due to the lack of an elastic body in the piezoresistive strain - gauge scheme, after long - term (frequent) stress or overload, it is difficult to fully recover in a short time, so it is extremely easy to generate creep, fatigue, and even structural damage, and the measurement stability is poor. At the same time, in the narrow space of the stylus, it is difficult to assemble 2 groups or 4 groups of micro - piezoresistive strain gauges, and the assembly accuracy will greatly affect the measurement accuracy of the nib pressure - sensing, and thus affect the effect of pressure - sensing grading.

[0005] Capacitive styluses are being increasingly applied to products such as smart phones, tablet computers, laptop computers, e-readers, electronic whiteboards, etc., imitating the interaction between a human finger and a capacitive stylus. However, most products only have the interaction between the tip of the pen and the capacitive screen, and do not have a fast switching function. For example, switching from a writing or drawing mode to an eraser, or switching from a hand tool to a pen tool. They only serve basic touch and writing functions. When a function switch is needed, separate operations need to be performed on the stylus or the writing medium to switch. For example, switching through a button on the stylus, switching the writing head, rotating, or switching through a virtual function switch button clicked on the writing medium screen, which brings an unpleasant writing experience. Summary of the Invention

[0006] Aiming at the technical problems and defects existing in capacitive styluses in the prior art, the object of the present invention is to provide a pressure-sensing - click fusion sensing system for a stylus using a single multi-channel capacitive detection chip, realizing pressure-sensing detection and touch (tap) trigger detection during the process of a user holding the pen body for writing, which is beneficial to realizing the control of writing precision and the fast switching of the functions / modes of the stylus, improving the user experience, while reducing the assembly cost and improving the assembly precision and reliability.

[0007] According to the first aspect of the object of the present invention, a pressure-sensing - click fusion sensing system for a capacitive stylus is proposed. The capacitive stylus has a pen body part and a nib part extending from the front end of the pen body part. The pressure-sensing - click fusion sensing system includes:

[0008] A crankshaft arranged along the longitudinal axis direction of the pen body part, having a body and a first shaft end and a second shaft end located at both ends of the body; the first shaft end of the crankshaft is connected to the nib part and can move synchronously with the nib part, and the opposite second shaft end of the crankshaft is slidably sleeved in the central hole of a first support part, and the first support part is located inside the pen body part and at the tail position;

[0009] An elastic limiting mechanism is arranged between the body of the crankshaft and the first support part, and is configured to store energy when the nib part is pressed and the crankshaft moves towards the first support part, so as to make the crankshaft move towards the initial position when the pressure weakens or is released;

[0010] A second support part is fixedly positioned with the pen body part and is located inside the cavity formed by the body of the crankshaft;

[0011] A first electrode plate and a second electrode plate are arranged in parallel between the second support part and an inner wall surface of the cavity to construct a bipolar plate capacitor model;

[0012] The third electrode plate is cylindrically pasted on the inner wall surface of the pen body part, located in the area held by human hands, and an open capacitance model is constructed between it and the pen body part;

[0013] The capacitance measurement unit has at least two detection channels. Among them, the first detection channel is connected to the first electrode plate and the second electrode plate, and is used to detect the capacitance values of the first electrode plate and the second electrode plate at different electrode plate spacings; the second detection channel is connected to the third electrode plate, and is used to detect the capacitance value under the finger click action when the user holds the pen body part;

[0014] The processor system is electrically connected to the capacitance measurement unit, and is used to obtain the nib stress of the nib part according to the capacitance value obtained by the first detection channel; and is used to determine the function switching behavior of the user according to the capacitance value obtained by the second detection channel, and control the preset function switching of the stylus pen.

[0015] As an optional implementation manner, the first support part and the second support part are configured as a part of the pen body part, and remain relatively stationary with respect to the pen body part.

[0016] As an optional implementation manner, the first support part and the second support part are configured as independent components fixed to the pen body part, and the two remain relatively stationary with respect to the pen body part.

[0017] As an optional implementation manner, the cavity formed by the body of the crankshaft is configured as a U-shaped cavity, and one of the two inner wall surfaces along the longitudinal axis direction of the pen body part is used to mount the first electrode plate or the second electrode plate.

[0018] As an optional implementation manner, the first electrode plate and the second electrode plate have the same structure, and are both parallel plate electrodes or both curved surface parallel plate electrodes.

[0019] As an optional implementation manner, the elastic limiting mechanism includes at least one spring.

[0020] As an optional implementation manner, the elastic limiting mechanism is sleeved on the outer peripheral surface of the second shaft end.

[0021] As an optional implementation manner, the pen body part, the nib part, the first shaft end and the second shaft end of the crankshaft, the first support part, the second support part, and the elastic limiting mechanism are arranged co-axially.

[0022] As an optional implementation manner, the processor system includes a nib pressure sensitivity measurement unit, which is configured to obtain the corresponding nib stress based on the capacitance value output by the first detection channel according to the following method:

[0023] σ = E * d σ = E * (kε0A) / C

[0024] Among them, σ represents the nib stress, and d σ represents the plate spacing between the first plate and the second plate under the loaded state; E represents the Young's modulus of the elastic limiting mechanism, A represents the plate area of the first plate and the second plate, k represents the relative permittivity, ε0 represents the vacuum permittivity, and C represents the capacitance value output by the first detection channel of the capacitance measurement unit.

[0025] As an optional implementation manner, the processor system includes a multi-click trigger processing unit, which is configured to determine whether two or more capacitance mutations exceeding a preset threshold range are detected within a preset response time according to the capacitance value output by the second detection channel, so as to determine whether the user triggers a function switching operation in the holding state.

[0026] According to the second aspect of the object of the present invention, a pressure-sensing and click-fusion sensing method for a capacitive stylus is also proposed, including the following steps:

[0027] Based on the comparison between the capacitance value output by the second detection channel and the calibrated holding detection threshold C0, a holding behavior detection is performed. When a holding behavior is detected, a nib pressure-sensing stress detection and a click trigger detection of the pen body are started:

[0028] The nib pressure-sensing stress detection includes:

[0029] Based on the force applied by the user when holding the capacitive stylus and writing on the writing medium surface, the nib part retracts inward toward the pen body part, and the crankshaft moves synchronously;

[0030] Based on the change in the plate spacing between the first plate and the second plate caused by the crankshaft movement, the capacitance values of different plate spacings detected and output by the first detection channel of the capacitance measurement unit are obtained; and

[0031] According to the capacitance values of different plate spacings detected and output by the first detection channel, the nib stress corresponding to the plate spacing is obtained;

[0032] The click trigger detection includes:

[0033] Within a preset response time, the capacitance difference value between the current holding capacitance value detected and output by the second detection channel of the capacitance measurement unit and the holding capacitance value obtained from the previous measurement is calculated, and it is determined whether the capacitance difference values obtained from at least two consecutive measurements both reach a preset first threshold. If so, it is determined that the user has a multi-touch behavior, and a response signal is output; otherwise, the capacitance detection and judgment continue.

[0034] As an optional implementation manner, the processor system obtains the nib stress corresponding to the plate spacing according to the capacitance values of different plate spacings detected and output by the first detection channel, including:

[0035] σ = E * d σ = E * (kε0A) / C

[0036] Wherein, σ represents the nib stress; d σ represents the plate distance between the first plate and the second plate in the loaded state; E represents the Young's modulus of the elastic limit mechanism, A represents the plate area of the first plate and the second plate, k represents the relative permittivity, ε0 represents the vacuum permittivity, and C represents the capacitance value output by the first detection channel of the capacitance measurement unit.

[0037] As an optional implementation manner, the holding detection threshold C0 of the capacitive stylus calibration is set as follows:

[0038] When the capacitive stylus is enabled for the first time, obtain the capacitance value C before holding pre ;

[0039] Based on the first holding behavior, obtain the capacitance value C after holding afta ; and

[0040] Set the holding detection threshold C0 = (C pre + C afta ) / 2.

[0041] As an optional implementation manner, the holding detection threshold C0 of the capacitive stylus calibration is set as follows:

[0042] When the capacitive stylus is enabled for the first time, obtain the capacitance value C before holding pre ;

[0043] Based on the first holding behavior, obtain the capacitance value C after holding afta ; and

[0044] Set the holding detection threshold C0 = k * (C pre + C afta ) / 2, where k represents the compensation coefficient and the initial value of k is 1.

[0045] As an optional implementation manner, the holding behavior is detected by comparing the capacitance value output by the second detection channel with the calibrated holding detection threshold C0, including:

[0046] Obtain the calibrated holding detection threshold C0;

[0047] Compare the holding capacitance value output by the second detection channel with the holding detection threshold C0:

[0048] When the holding capacitance value is greater than or equal to the aforementioned holding detection threshold C0, it is determined that there is a holding behavior; otherwise, it is determined that there is no holding behavior.

[0049] The pressure-sensitivity and click fusion sensing system for a stylus proposed by the present invention can measure the capacitance values of two channels simultaneously based on a single multi-channel capacitance measurement chip, and can implement the functions of tip pressure-sensitivity grading and multi-click triggering of the pen body on the stylus. Through the multi-click triggering method based on the high-precision capacitance measurement principle, stable and reliable stylus operations can be achieved under the condition of controllable cost, such as quickly switching between input and erasure states, etc. Description of the Drawings

[0050] Figure 1 is a schematic structural diagram of a capacitive stylus according to an embodiment of the present invention.

[0051] Figure 2 is Figure 1 a front view of the capacitive stylus according to the embodiment, in which the internal structure of the pen body part is partially illustrated.

[0052] Figure 3 is Figure 1 a sectional view of the capacitive stylus according to the embodiment, in which an example of the pressure-sensitivity grading induction mechanism is shown.

[0053] Figure 4 is a schematic structural diagram of the crankshaft of the capacitive stylus according to an embodiment of the present invention.

[0054] Figure 5 is a schematic diagram of the cooperation structure of the crankshaft of the capacitive stylus according to an embodiment of the present invention and two supporting parts.

[0055] Figure 6 is a schematic diagram of the pressure-sensitivity grading induction device of the capacitive stylus according to an embodiment of the present invention.

[0056] Figure 7 is a schematic diagram of a capacitive stylus held by a finger according to an embodiment of the present invention.

[0057] Figure 8 is a schematic diagram of the position of the third electrode plate in the capacitive stylus according to an embodiment of the present invention.

[0058] Figure 9 is a flowchart of the multi-click triggering processing method according to an embodiment of the present invention, taking double-click triggering as an example.

[0059] Figure 10 is a schematic diagram of the holding state recognition process according to an embodiment of the present invention.

[0060] Figure 11 is a schematic diagram of the pressure-sensitivity and click fusion sensing system according to an embodiment of the present invention.

[0061] Figure 12 is a schematic diagram of the pressure-sensitivity and click fusion sensing method according to an embodiment of the present invention.

[0062] The meanings of the reference numerals are as follows:

[0063] 100 - capacitive stylus;

[0064] 10 - pen body part; 20 - pen tip part;

[0065] 30 - crankshaft; 31 - body; 32 - first shaft end; 33 - second shaft end; 35 - cavity; 36 - guiding part;

[0066] 40 - first support part;

[0067] 50 - elastic limiting mechanism;

[0068] 60 - second support part;

[0069] 101 - first electrode plate; 102 - second electrode plate; 103 - third electrode plate;

[0070] 200 - capacitance measurement part;

[0071] 300 - processor system; 301 - pen tip pressure sensing measurement part; 302 - multi - click trigger processing part;

[0072] 400 - desktop computer, 401 - reading interface. Detailed implementation manners

[0073] In order to better understand the technical content of the present invention, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.

[0074] In the present disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to cover all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of many ways, because the concepts and embodiments disclosed in the present invention are not limited to any implementation manner. Additionally, some aspects of the present invention can be used alone, or in any suitable combination with other aspects of the present invention.

[0075] Combined with Figure 1-6 The capacitive stylus 100 of the illustrated embodiment includes a pen body part 10, a pen tip part 20, and a pressure - sensitive grading sensing device located inside the pen body part 10. The pressure - sensitive grading sensing device is used to sense and output the stress generated by the force applied during writing when the pen tip part 20 slides on the surface of the writing medium, that is, pressure - sensitive output. Thus, the capacitive stylus 100 and / or the processor configured in the writing medium can achieve various controls and switches based on this pressure - sensitive output, such as controlling the implementation of handwriting with different thicknesses.

[0076] AsFigure 2 As shown, the nib portion 20 can be configured to be connected to the inside of the pen body portion 10 through a shaft.

[0077] As Figure 1 shown, for ease of explanation, the two ends of the pen body portion 10 are respectively defined as the front end 11 (i.e., the head) and the tail end 12 opposite to the front end. The nib portion 20 extends from the position of the front end 11 of the pen body portion 10, for example, extends from the pen body portion 10 based on the shaft. Figure 2 As

[0078] Combined with Figure 2-4 As shown, inside the pen body portion 10, a crankshaft 30 is arranged along the longitudinal axis direction of the pen body portion 10. The crankshaft 30 has a body 31 and a first shaft end 32 and a second shaft end 33 located at both ends of the body 31, as Figure 3 shown, 4 shown.

[0079] The first shaft end 32 of the crankshaft 30 is connected to the nib portion 20. For example, a rigid fixed connection is formed between the two through means such as threads and key connections.

[0080] The opposite second shaft end 33 of the crankshaft 30 is slidably sleeved in the central hole 41 of a first support portion 40. As Figure 3 shown, the first support portion 40 is located inside the pen body portion 10 and at the tail position. A central hole 41 is configured coaxially with the axis of the pen body portion 10 in its longitudinal axis direction, and the central hole 41 extends towards the tail end 12 of the pen body portion 10.

[0081] In an alternative embodiment, the first support portion 40 is configured as a part of the pen body portion 10.

[0082] In an alternative embodiment, the first shaft end 32 and the second shaft end 33 have the same cross-sectional shape and dimensions. For example, it involves a long cylindrical shaft, which is beneficial for sliding movement and guiding at both ends. Along the aforementioned longitudinal axis direction, the length of the second shaft end 33 is greater than the length of the first shaft end 32.

[0083] Combined with Figure 3 shown, 5 In the example shown, based on the connection between the first shaft end 32 of the crankshaft 30 and the nib portion 20, when the nib portion 20 of the capacitive stylus 100 slides on the surface of a writing medium (such as the display screen of a tablet computer device equipped with a capacitive screen) during writing, the nib portion 20 moves towards the tail end 12 direction under the writing pressure, thereby driving the crankshaft 30 to move synchronously, and causing the second shaft end 33 of the crankshaft 30 to slide towards the tail 12 direction in the central hole 41.

[0084] As Figure 3 shown, 5As shown, an elastic limit mechanism 50 is disposed between the body 31 of the crankshaft 30 and the first support portion 40. For example, taking the helical spring shown in the figure as an example, it is sleeved on the outer periphery of the second shaft end 33 of the crankshaft 30, stores energy when the pen tip portion 20 is pressed and the crankshaft 30 moves toward the first support portion 40, and causes the crankshaft 30 to move toward the initial position when the above-mentioned pressure weakens or is released.

[0085] Combined with Figure 3 、 5 , as the second shaft end 33 of the crankshaft 30 slides in the central hole 41 toward the tail portion 12, the elastic limit mechanism 50 (taking the helical spring as an example) is compressed and stores energy. Thus, when the pressure is released or relieved, the elastic limit mechanism 50 after storing energy will drive the crankshaft 30 to move toward the front end 11 and restore its initial position.

[0086] Combined with Figure 3 、 4 As shown in FIGS. 5, a cavity 35 is formed in the body 31 of the crankshaft 30, especially a U-shaped cavity. In the design of this U-shaped cavity, the surface of one of the two inner wall surfaces along the longitudinal axis direction of the pen body portion 10 is used to mount the first electrode plate 101 or the second electrode plate 102. The other electrode plate is mounted on the surface of the second support portion 60 located in the U-shaped cavity, and the two electrode plates are arranged face to face.

[0087] The second support portion 60 is disposed inside the U-shaped cavity, and the second support portion 60 is configured as a part of the pen body portion 10, so that a fixed position relationship is maintained between it and the pen body portion 10. And, a certain gap is left between the side wall surface of the second support portion 60 and the side wall surface of the cavity 35 to facilitate the installation of the two capacitor electrode plates.

[0088] Particularly preferably, the surfaces of the second support portion 60 and the inner wall surface of the cavity 35 are both flat surfaces, which is conducive to mounting the capacitor electrode plates.

[0089] Combined with the figure shown, a guiding portion 36 is disposed on the surface of the other of the two inner wall surfaces of the U-shaped cavity, whereby the body 31 can move along the guiding portion 36.

[0090] Combined with Figure 3 、 5 In the example shown in FIGS. 6, the paired first electrode plate 101 and the second electrode plate 102 are respectively located on the surfaces of a pair of inner wall surfaces of the second support portion 60 and the cavity 35 that face each other. In Figure 3 the example shown, the first electrode plate 101 and the second electrode plate 102 are fixed by pasting to construct a bipolar capacitor model.

[0091] The first electrode plate 101 and the second electrode plate 102 are respectively installed in the right space between the second support portion 60 and the cavity 35.

[0092] Based on the relative static state (unchanged relative position) of the second support portion 60 and the pen body portion 10, when the tip portion 20 is pressed and the crankshaft 30 undergoes a displacement in the direction of the tail portion 14, the electrode plate spacing d between the first electrode plate 101 and the second electrode plate 102 will change. As a result, the static capacitance between the first electrode plate 101 and the second electrode plate 102 changes. Such a change can be sensed and detected by a capacitance measurement chip, and a corresponding capacitance value is output.

[0093] Combined with the illustrated example, when the tip portion 20 is pressed and displaced, both the first shaft end 32 and the second shaft end 33 move synchronously in the same direction. As Figure 3 shown in the example, the second shaft end 33 undergoes displacement within the aforementioned central hole 41 and is guided by the central hole 41 to maintain its movement along the central axis direction of the pen body portion 10.

[0094] In an alternative example, at least partially a nested guiding relationship is formed between the front end 11 of the pen body portion 10 and the first shaft end 32 of the crankshaft 30, such that the first shaft end 32 of the crankshaft 30 can be guided during movement and maintain its movement along the central axis direction of the pen body portion 10.

[0095] In an alternative example, the first support portion 40 and the second support portion 60 are configured as independent components fixed to the pen body portion 10, and both are in a relatively static state with respect to the pen body portion 10. Thus, during the movement of the crankshaft 30 between them, the electrode plate spacing d between the first electrode plate 101 and the second electrode plate 102 changes due to the change in the spacing between the inner wall surface of the cavity of the crankshaft 30 and the second support portion 60, thereby causing a change in the static capacitance between the first electrode plate 101 and the second electrode plate 102.

[0096] Of course, in other embodiments, the relationship between the first support portion 40, the second support portion 60, and the crankshaft 30 can also be configured in other suitable ways, such that one of the capacitor electrode plates (taking the first electrode plate 101 as an example) can be rigidly connected to the tip portion 20 and move synchronously, and can be limited by a spring to avoid overloading; at the same time, the other capacitor electrode plate (taking the second electrode plate 102 as an example) is rigidly connected to the housing of the pen body portion 10 or is part of the housing and is always in a relatively static state with respect to the pen body portion 10.

[0097] In some examples, both the first support portion 40 and the second support portion 60 are block-shaped components perpendicular to the longitudinal axis direction of the pen body portion 10.

[0098] Combined withFigure 6 In the example shown, the capacitance measuring unit 200 may use a multi-channel capacitance detection chip, for example, the high-precision capacitance sensor measurement chip PMDS-F4 of Nanjing Pai Rui Semiconductor Co., Ltd. is used as an example for illustration. The first detection channel of the capacitance measuring unit 200 is connected to the first electrode plate 101 and the second electrode plate 102 respectively, and is used to detect the change of the static capacitance of the first electrode plate 101 and the second electrode plate 102 at different electrode plate spacings, and output the capacitance value.

[0099] Therefore, through the pressure-sensing graded sensing mechanism composed of the crankshaft 30, the first support part 40, the elastic limiting mechanism 50 (taking a coil spring as an example), the second support part 60, the first electrode plate 101 and the second electrode plate 102 proposed in the aforementioned embodiment of the present invention, the stress load of the pen tip can be sensed based on the change in the electrode spacing between the first electrode plate 101 and the second electrode plate 102, thereby realizing a stylus capacitive pressure-sensing graded sensing output with reliable structure and accurate measurement.

[0100] As a preferred example, the pen body 10 , the pen tip 20 , the first shaft end 32 and the second shaft end 33 of the crankshaft 30 , the first support part 40 , the second support part 60 , and the elastic limiting mechanism 50 are arranged coaxially.

[0101] Combination Figure 3 , 6 As shown, the pressure-sensing graded sensing mechanism of the embodiment of the present invention is configured such that the plate spacings in no-load, loaded, fully loaded, and overloaded states are as follows:

[0102] No-load: d = d0, d0 represents the plate spacing under no-load, d0 = 0;

[0103] Load: d = d σ , d σ Indicates the distance between the plates under load, d σ =σ / E, where σ is the pen tip stress and E is the Young's modulus of the elastic limit mechanism, which is a constant;

[0104] Full load: d = D, where D is the maximum compression of the elastic limit mechanism, i.e. diameter * number of turns, which is a constant;

[0105] Overload: Due to the existence of the spring limit mechanism, overload cannot occur, so it will not have a destructive effect on the capacitive pressure sensing graded structure, and the elastic limit mechanism plays a protective role.

[0106] Therefore, in the embodiment of the present invention, the coil spring is in a relatively free state in the no-load state, the two capacitor plates (i.e., the first plate 101 and the second plate 102) are in close contact with each other, and the static capacitance output C is close to infinity. Since the stylus is in a non-input state more often during its life cycle, the pressure-sensing graded sensing mechanism of the embodiment of the present invention can better protect the measurement structure.

[0107] Meanwhile, in the loaded state, the helical spring is continuously compressed, the first electrode plate 101 and the second electrode plate 102 are separated and gradually pulled apart, the static capacitance output C continuously decreases, and maintains a highly reliable and stable linear relationship with the compression ratio of the helical spring, enabling high-resolution grading of the nib pressure sensitivity, such as 4096 or higher.

[0108] Furthermore, when the capacitive stylus 100 proposed by the present invention accidentally drops, due to the double limit protection of the elastic limit mechanism 50 and the second support portion 60, the first electrode plate 101 and the second electrode plate 102 will not damage the pressure sensing device due to instantaneous impact, greatly improving the anti-drop performance and reliability of the capacitive stylus.

[0109] As described above, in the embodiment of the present invention, the distance between the first electrode plate 101 and the second electrode plate 102 increases as the pressure received by the detected nib portion increases. As shown in the figure, the second electrode plate 102 is fixed to the side wall of the cavity 35 formed by the body 31 of the crankshaft 30. As the pressure received by the nib portion increases, the distance between it and the first electrode plate 101 fixed to the second support portion 60 (such as constituting a part of the pen body portion) is continuously enlarged, thereby realizing capacitance output detection and pressure detection. At the same time, combined with Figure 2 、 3 As shown, based on the design of the pressure sensitivity grading induction device and measurement method proposed by the present invention, due to the presence of the elastic limit mechanism 50 (such as a helical spring) between the crankshaft 30 and the first support portion 40, restricted by the maximum deformation amount of the elastic limit mechanism 50 and its limiting effect, no overload situation will occur, so it will not cause a destructive impact on the capacitive pressure sensitivity grading structure. At the same time, combined with the elastic limit mechanism and the second support portion 60 to play a double protection role, under accidental dropping or instantaneous strong pressure applied to the nib portion caused by other reasons, the pressure sensing device will not be damaged, improving the anti-drop performance and reliability.

[0110] It should be understood that the aforementioned elastic limit mechanism 50 for realizing overload protection can also be designed in other appropriate ways, not limited to helical springs. For example, wave springs can also be used.

[0111] In the embodiment of the present invention, through the configured capacitance measurement unit 200, such as selecting a high-resolution capacitance measurement chip, which is electrically connected to the nib pressure sensitivity measurement unit 300 configured in the pen body portion 10, based on the value of the static capacitance output by the capacitance measurement unit 200, the corresponding nib stress is obtained.

[0112] Combined with Figure 7 、 8As shown, inside the pen body 10, a third electrode plate 103 is also disposed, such as a thin plate-shaped electrode, which is cylindrically pasted on the inner wall surface of the pen body 10, located in the area held by the human hand, and an open capacitance model is constructed between the pen body.

[0113] Thus, in combination with Figure 7 , 8 As shown, it can be connected to the third electrode plate 103 through the second detection channel of the capacitance measurement unit 200, for detecting the capacitance value when a finger click action occurs when the hand 1000 holds the pen body 10, and outputting it.

[0114] In combination with Figure 6 As shown, a processor system 300 is also provided inside the pen body 10, such as a processing chip integrated on a PCB circuit board, especially a low-power embedded processing chip, to realize the control of the entire stylus. Especially in the embodiment of the present invention, the processor system 300 is configured to obtain the nib stress of the nib based on the capacitance value obtained through the first detection channel, and to determine the function switching behavior of the user according to the capacitance value obtained through the second detection channel, and control the preset function switching of the stylus.

[0115] The processor system 300 optionally has a nib pressure sensing measurement unit 301 and a multi-tap trigger processing unit 302.

[0116] Among them, the nib pressure sensing measurement unit 301 is configured to obtain the corresponding nib stress based on the capacitance value output by the first detection channel according to the following method:

[0117] σ = E * d σ = E * (kε0A) / C

[0118] Among them, σ represents the nib stress, and d σ represents the electrode plate spacing between the first electrode plate 101 and the second electrode plate 102 in the loaded state; E represents the Young's modulus of the elastic limiting mechanism 50, A represents the electrode plate area of the first electrode plate 101 and the second electrode plate 102, k represents the relative dielectric constant, ε0 represents the vacuum permittivity, and C represents the capacitance value output by the first detection channel of the capacitance measurement unit 200.

[0119] Among them, the multi-tap trigger processing unit 302 is configured to based on the capacitance value output by the second detection channel, and judge whether two or more capacitance mutations exceeding the preset threshold range are detected within the preset response time, thereby judging whether the user triggers a function switching operation in the holding state.

[0120] As an optional example, the multi-tap trigger processing unit 302 is configured to judge whether the user triggers a function switching operation in the holding state in the following manner:

[0121] Obtain the holding detection threshold C0 of the calibrated capacitive stylus;

[0122] During the use of the capacitive stylus, obtain the holding capacitance value output C in the holding state output by the second detection channel meas_n ;

[0123] In response to C meas_n reaching the holding detection threshold C0, enter the user multi-tap touch behavior detection mode; otherwise, continuously obtain the holding capacitance value output C meas_n and continuously determine whether to enter the detection mode;

[0124] Among them, in the user multi-tap touch behavior detection mode, within a preset response time, calculate the capacitance difference value based on the currently measured holding capacitance value and the previously measured holding capacitance value, and when the capacitance difference values obtained from at least two consecutive measurements both reach the preset first threshold, determine that the user has a multi-tap touch behavior and output a response signal.

[0125] In this regard, we will give a more specific description in the following examples.

[0126] As Figure 7-10 shown in the example, for the multi-tap trigger detection according to the embodiment of the present invention, for the holding and switching behavior detection of the capacitive stylus, it is implemented based on an open capacitance model of a single capacitor plate, which is a typical open capacitance model. Combining Figure 7 , 8 shown, the essence of double-click or multi-tap trigger is the spatial conductivity characteristics generated by the user's entire hand on the measurement plate (single plate) mounted inside the pen body when the user holds the pen, which is further reflected through the detection output of the capacitance value. The capacitance model therein is a single capacitor plate model, and the dielectric constant of the user's hand (close to 80 of water) and the air dielectric constant (close to 1) act on the capacitor plate together.

[0127] Figure 7 In the example shown, reference numeral 1000 represents the user's finger, holding the pen body 10 of the capacitive stylus. The dotted part represents the third plate 103 configured inside the capacitive stylus 100, which is in the shape of a thin cylinder.

[0128] Since the human body dielectric constant is much larger than that of air, the contact area between the hand skin and the pen body is the main interference factor affecting the capacitance output. At the same time, considering the interference of the dynamic change of the user's pen-holding posture on the capacitance measurement, in the embodiment of the present invention, it is proposed to perform capacitance output by tapping or touching the position where the plate is located with the finger two or more times. Based on a fluctuating reference capacitance curve, identify the number of times N thres of behaviors that continuously exceed the set threshold C k, based on which the switching actions used are identified, achieving more stable and reliable user behavior identification.

[0129] In the embodiment of the present invention, it is set that the continuous exceeding of the set threshold C thres Number of behaviors N k It can be 2 (double-click) or 3 (triple-click), which means that the user is considered to have entered a quick switch behavior.

[0130] It should be understood that since the spatial electric field output model of the open capacitor plate is affected by both the user's holding behavior and the spatial electric field (such as a mobile phone receiving a call, etc.), in the embodiments of the present invention, in order to further eliminate interference and improve the robustness of the system, or to achieve more quick switching functions, more than two multi-touch triggers, i.e., N k Greater than or equal to 3, in some embodiments, can be set and implemented according to the present invention.

[0131] Combination Figure 8 The design of the capacitive stylus pen 100 shown briefly shows the pen body 10 and the third electrode plate 103 disposed inside the pen body, the capacitance measuring unit 200 , the processor system 300 and the communication module 500 .

[0132] The third electrode plate 103 is in the form of a thin sheet and is cylindrically attached to the inner wall surface of the pen body 10 of the capacitive touch pen and is located in the area where the human hand holds the pen.

[0133] The capacitance measuring unit 200 is used to detect the capacitance value output of the capacitance model formed between the pen body 10 of the capacitive stylus and the third electrode plate 103 when a person holds the capacitive stylus. As an optional example, a capacitance measurement chip in the prior art can be used for design. In the example of the present invention, the high-precision capacitance sensor measurement chip PMDS-F4 of Nanjing Pai Rui Semiconductor Co., Ltd. is used as an example for explanation.

[0134] The second detection channel of the capacitance measuring unit 200 is connected to the third electrode plate 103 and is used to detect and output the capacitance value when a finger click action occurs when the user's hand 1000 holds the pen body 10 .

[0135] The processor system 300 is connected to the capacitance measuring unit 200 and the communication module 500 respectively.

[0136] As described above, the processor system 300 can be implemented using a low-power processing chip, which can determine the user's quick switching behavior and control the switching of the mode or function of the capacitive stylus according to the capacitance value output by the second channel of the capacitance measurement unit 200. For example, the switching from the writing or drawing mode to the eraser, or the switching from the hand tool to the pen tool, etc. It should be understood that the programs and instructions executed for such switching operations can be implemented according to the instruction sets and program components in the prior art.

[0137] The communication module 500 is used to implement data communication and interaction between the capacitive stylus 100 and external devices, such as data communication with a desktop computer, a laptop computer, a handheld computer, and a mobile intelligent processing device. In Figure 2 this, taking the desktop computer 400 as an example for illustration, where the label 401 represents its reading interface.

[0138] In the embodiment of the present invention, the communication module 500 is described by taking a Bluetooth module as an example.

[0139] It should be understood that desktop computers and laptop computers are usually configured with a display screen and are electrically connected to the capacitive stylus 100 and / or the writing medium, and can display the written content, the pen tip and / or the writing trajectory.

[0140] It should be understood that the drawings and the foregoing embodiments are intended to provide an exemplary description of the design of the capacitive stylus. Optionally included inside the capacitive stylus are but not limited to the following components / modules: a memory for storing data and program instructions, wires for implementing electrical connections, a battery module and / or a charge and discharge module for implementing power supply, a PCB board integrating one or more functional circuits / chips, and a display module for implementing information representation including but not limited to a small display screen, an LED light group, etc., which can be designed and implemented according to the specific functions and requirements of the capacitive stylus.

[0141] Combined with Figure 7-9 as shown, the implementation of the multi-tap trigger processing method for a capacitive stylus according to an embodiment of the present invention includes the following steps:

[0142] Obtain the calibrated holding detection threshold C0 of the capacitive stylus;

[0143] During the use of the capacitive stylus, detect the holding capacitance value output C meas_n ;

[0144] In response to C meas_n reaching the holding detection threshold C0, enter the user multi-tap touch behavior detection mode; otherwise, continuously obtain the holding capacitance value output C meas_nAnd continuously determine whether to enter the detection mode until a preset condition is reached;

[0145] Among them, in the user multi-touch behavior detection mode, within a preset response time, calculate the capacitance difference value based on the current measured holding capacitance value and the previously measured holding capacitance value, and when the capacitance difference values obtained from at least two consecutive measurements both reach a preset first threshold, determine that the user has a multi-touch behavior and output a response signal.

[0146] It should be understood that the aforementioned preset conditions refer to the shutdown operation, disconnection operation, low battery operation, etc. of the stylus, which can be pre-set by the user or pre-configured by the stylus at the factory.

[0147] Combined with Figure 9 、 10 As shown in the example, in the embodiment of the present invention, in order to further eliminate the probability of false triggering, after the user holds the capacitive stylus, it is first necessary to perform an effective detection of the holding state. Only when it is recognized that the current operation on the capacitive stylus is a real and effective holding behavior, can the detection of double-click or multi-level triggering be entered.

[0148] For this reason, we usually choose to complete the initialization and setting of the holding threshold during the production process or factory inspection of the capacitive stylus, that is, when the stylus is first held, measure and read the capacitance values before and after holding, and accordingly preset the holding detection threshold.

[0149] In the embodiment of the present invention, after each determination that the user has a multi-touch behavior and outputs a response signal, the capacitance difference value and the time count are reset, and the user multi-touch behavior detection mode is re-entered to start the capacitance detection of the holding state and the recognition of the user switching behavior.

[0150] As an optional implementation manner, the calibration of the holding detection of the capacitive stylus, and the calibration of the holding detection threshold C0 of the capacitive stylus includes:

[0151] When the capacitive stylus is first enabled, obtain the capacitance value C before holding pre ;

[0152] Based on the first holding behavior, obtain the capacitance value C after holding afta ; and

[0153] Set the holding detection threshold C0 = (C pre + C afta ) / 2.

[0154] Thus, a preset holding detection threshold C0 can be configured in the memory of the capacitive stylus. When the capacitive stylus is used subsequently and the holding behavior is recognized, it is called by the processor system for judgment and corresponding processing.

[0155] It should be understood that during the subsequent use of the capacitive stylus, if the measured output capacitance value is less than the configured holding detection threshold C0, it is considered that there is no effective holding behavior, and there is no need to enter the double-click or multi-click trigger recognition process, that is, the measurement state. Only when the measured output capacitance value is greater than or equal to the configured holding detection threshold C0, the subsequent double-click or multi-click trigger recognition process is performed.

[0156] As another implementation, for the holding detection calibration of the capacitive stylus, calibrating the holding detection threshold C0 of the capacitive stylus includes:

[0157] When the capacitive stylus is first enabled, obtain the capacitance value C before holding pre ;

[0158] Based on the first holding behavior, obtain the capacitance value C after holding afta ; and

[0159] Set the holding detection threshold C0 = k * (C pre + C afta ) / 2, where k represents the compensation coefficient and the initial value of k is 1.

[0160] In this embodiment, due to the wear, erosion, etc. of the pen body surface during the subsequent use of the capacitive stylus, or the air erosion, oxidation, etc. of the internal electrode plates, an adjustable compensation coefficient k is configured to compensate for the change problem of the calibration value caused by use.

[0161] As an optional embodiment, the compensation coefficient k can be set to be adjusted through testing, maintenance, or through a preset configuration program.

[0162] As an optional example, for a capacitive stylus that has been used normally for more than a preset time limit range, a compensation coefficient k according to different usage durations is preset and automatically modified inside the capacitive stylus without being perceived by the user. For example, starting from the user's first use of the capacitive stylus (such as the first measurement of the capacitance value), time counting is performed, and after a preset duration (such as 1 year, 1.5 years, 2 years, etc.), the compensation coefficient k is automatically updated in a predetermined manner.

[0163] As an alternative implementation mode, within a preset time period, calculate the capacitance difference value based on the current measured grip capacitance value and the previously measured grip capacitance value, and when the capacitance difference values obtained from at least two consecutive measurements both reach a preset first threshold, it is determined that the user has a multi-touch behavior, including:

[0164] Continuously obtain the output C of the grip capacitance value in the user's grip state meas_n+i ; where i represents the capacitance value sampling measurement sequence, starting from 1.

[0165] When the difference value ΔC of the output of the grip capacitance value starting from any j-th time n+j reaches the preset first threshold C thres , j ≤ i, start time counting, and continue to obtain the difference value ΔC of the output of the (j + 1)-th grip capacitance value n+j+1 :

[0166] In response to the difference value ΔC of the output of the (j + 1)-th grip capacitance value n+j+1 reaching the preset first threshold C thres , further judge the time difference ΔT from the j-th to the (j + 1)-th behavior. When ΔT is within the preset response time T thres , it is determined that the user has a multi-touch behavior and output a response signal.

[0167] Among them, in response to the difference value ΔC of the output of the (j + 1)-th grip capacitance value n+j+1 not reaching the preset first threshold C thres , return to continue obtaining the output of the grip capacitance value in the user's grip state.

[0168] Among them, in response to the time difference ΔT exceeding the preset response time T thres range, return to continue obtaining the output of the grip capacitance value in the user's grip state.

[0169] In an embodiment of the present invention, the difference value ΔC of the output of the grip capacitance value starting from any j-th time n+j , its calculation method is to subtract the capacitance value obtained from the previous measurement (i.e., the (j - 1)-th time) from the capacitance value obtained from the current j-th measurement to obtain the capacitance value difference, that is, C meas_n+j -C meas_n+j-1 .

[0170] When j = i = 1, the difference value ΔC n+1 =C meas_n+1 -C meas_n represents the difference between the capacitance value obtained from the first detection in the measurement mode and the capacitance value C meas_n of the previous measurement.

[0171] When ΔC n+1Meet the condition that it is greater than or equal to a preset first threshold C thres When the threshold condition is met, the measurement result of the second capacitance value is further obtained, and ΔC n+2 = C meas_n+2 - C meas_n+1 is further calculated, and it is further determined whether ΔC n+2 meets the threshold condition that it is greater than or equal to a preset first threshold C thres When both threshold conditions are met simultaneously, it is determined whether the time counting range of the two detection actions is within a predetermined preset response time T thres range. If it is within the preset response time T thres range, it is determined as the double-click trigger action of the user, the double-click behavior is recognized, and a response signal is output to trigger the switching function.

[0172] Thus, according to whether there is a capacitance difference value exceeding the threshold preset first threshold C thres in two consecutive capacitance measurements within a preset response time T thres , through the double-click or above judgment, it is determined accordingly that the double-click behavior is recognized and the switching function is triggered.

[0173] In the embodiment of the present invention, in order to eliminate the capacitance drift caused by the user's pen-holding dynamics, a difference value is introduced as a reference in the above-mentioned finger trigger judgment to eliminate the interference of the human hand holding dynamics and improve the measurement and recognition progress and accuracy.

[0174] In some other embodiments, within a preset response time T thres range, based on the acquisition of the capacitance difference value, and when the capacitance difference values obtained in at least three consecutive measurements all reach the preset first threshold, it is determined that the user has a multi-touch behavior.

[0175] Thus, through the triple-click or above judgment, it is determined accordingly that the double-click behavior is recognized and the switching function is triggered.

[0176] In an alternative embodiment of the present invention, as shown in combination with Figure 12 , in order to reduce power consumption, that is, the nib pressure stress detection and the finger click trigger detection are not continuously performed, but are performed when the capacitive stylus is effectively held, thereby reducing power consumption. For example, the subsequent finger click trigger detection and the nib pressure stress detection can be started based on the detection of the holding behavior.

[0177] In combination with Figure 1 、 2, as shown in Figures 7, 8, and 11, schematically illustrates the fusion detection principle of integrating tip pressure sensing stress detection and finger click trigger detection within the entire capacitive stylus. It can be seen that through the single-chip implementation solution of the present invention, only one multi-channel capacitance measurement chip is required to simultaneously achieve the above two or more functions. At the same time, in the design of the present invention, the assembly difficulty of parts is low, the assembly accuracy and reliability are improved, space is saved, and the BOM cost is controllable.

[0178] The structural design of the pressure-sensitive grading induction device of the capacitive stylus proposed by the present invention is simple and reliable. The assembly space and process are easy to implement, with high precision and not subject to overload damage, improving the effect of pressure-sensitive grading. At the same time, compared with the existing design of 2 or 4 groups of piezoresistive strain gauges and then transformed through a high-resolution analog-to-digital converter ADC, the present invention can use a single capacitance measurement chip and simple calculations to achieve measurement, with low cost and better assembly accuracy.

[0179] It should be understood that the figures and the foregoing embodiments are intended to provide an exemplary description of the design and implementation principle of the pressure-sensitive grading induction device of the capacitive stylus. Optionally included within the capacitive stylus 100 are, but are not limited to, the following components / modules: wires for achieving electrical connection, a battery module and / or a charge and discharge module for achieving power supply, a PCB board integrating one or more functional circuits / chips, a communication module for achieving communication between the capacitive stylus 100 and an external device, and a display module for achieving information representation, including but not limited to a small display screen, an LED light group, etc.

[0180] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by what is defined in the claims.

Claims

1. A pressure-sensing - click fusion sensing system for a capacitive stylus, the capacitive stylus having a pen body portion (10) and a nib portion (20) extending from the front end of the pen body portion (10), characterized in that, The pressure-sensing and click-fusion sensing system includes: A crankshaft (30) arranged along the longitudinal axis of the pen body (10), having a body (31) and a first shaft end (32) and a second shaft end (33) located at both ends of the body (31); the first shaft end (32) of the crankshaft (30) is connected to the nib part (20) and can move synchronously with the nib part (20), and the opposite second shaft end (33) of the crankshaft (30) is slidably inserted into the central hole (41) of a first support part (40), and the first support part (40) is located inside the pen body (10) and at the tail position; An elastic limiting mechanism (50), arranged between the body (31) of the crankshaft (30) and the first support part (40), and is configured to store energy when the nib part (20) is pressed and the crankshaft (30) moves towards the first support part (40), so as to make the crankshaft (30) move towards the initial position when the pressure weakens or is released; A second support part (60), which maintains a fixed position relationship with the pen body (10) and is located in the cavity (35) formed by the body (31) of the crankshaft (30); A first electrode plate (101) and a second electrode plate (102), which are arranged in parallel between the second support part (60) and an inner wall surface of the cavity (35) to construct a bipolar plate capacitance model; A third electrode plate (103), which is cylindrically pasted on the inner wall surface of the pen body (10) and is located in the area held by the human hand, and constructs an open capacitance model with the pen body (10); A capacitance measurement unit (200), having at least two detection channels, wherein the first detection channel is connected to the first electrode plate (101) and the second electrode plate (102) for detecting the capacitance values of the first electrode plate (101) and the second electrode plate (102) at different electrode plate spacings; the second detection channel is connected to the third electrode plate (103) for detecting the capacitance value under the finger click action when the pen body 10 holds the pen body (10); the distance between the first electrode plate (101) and the second electrode plate (102) increases as the pressure on the detected nib part increases; A processor system (300), electrically connected to the capacitance measurement unit (200), for obtaining the nib stress of the nib part (20) according to the capacitance value obtained from the first detection channel; and for determining the function switching behavior of the user according to the capacitance value obtained from the second detection channel and controlling the preset function switching of the stylus.

2. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The processor system (300) includes a nib pressure sensing measurement unit (301), which is configured to obtain the corresponding nib stress based on the capacitance value output by the first detection channel according to the following method: σ = E * d σ = E * (kε0A) / C Among them, σ represents the nib stress, and d σ represents the plate distance between the first plate (101) and the second plate (102) under the loaded state; E represents the Young's modulus of the elastic limit mechanism (50), A represents the plate area of the first plate (101) and the second plate (102), k represents the relative permittivity, ε0 represents the vacuum permittivity, and C represents the capacitance value output by the first detection channel of the capacitance measurement unit (200).

3. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The first support part (40) and the second support part (60) are constructed as part of the pen body (10) and remain relatively stationary with respect to the pen body (10).

4. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The first support part (40) and the second support part (60) are constructed as independent components fixed to the pen body (10), and both remain relatively stationary with respect to the pen body (10).

5. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The cavity (35) formed by the body (31) of the crankshaft (30) is configured as a U-shaped cavity, and the surface of one of the two inner wall surfaces along the longitudinal axis direction of the pen body (10) is used to mount the first electrode plate (101) or the second electrode plate (102).

6. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 5, wherein The first electrode plate (101) and the second electrode plate (102) have the same structure, and both are parallel plate electrodes or both are curved surface parallel plate electrodes.

7. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The elastic limiting mechanism (50) includes at least one spring.

8. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 7, wherein The elastic limiting mechanism (50) is sleeved on the outer peripheral surface of the second shaft end (33).

9. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 1, wherein The pen body (10), the pen tip part (20), the first shaft end (32) and the second shaft end (33) of the crankshaft (30), the first support part (40), the second support part (60), and the elastic limiting mechanism (50) are arranged co-axially.

10. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to any one of claims 1-9, characterized in that, The processor system (300) includes a multi-tap trigger processing unit (302), which is configured to judge whether two or more capacitance mutations exceeding a preset threshold range are detected within a preset response time according to the capacitance value output by the second detection channel, so as to judge whether the user triggers a function switching operation in the holding state.

11. The pressure-sensing and click-fusion sensing system for a capacitive stylus according to claim 10, wherein The multi-tap trigger processing unit (302) is configured to judge whether the user triggers a function switching operation in the holding state in the following manner: Obtain the holding detection threshold C0 of the calibrated capacitive stylus; During the use of the capacitive stylus, obtain the holding capacitance value output C in the holding state output by the second detection channel meas_n ; In response to C meas_n When the grip detection threshold C0 is reached, enter the user multi-tap touch behavior detection mode; otherwise, continuously obtain the grip capacitance value output C meas_n And continuously determine whether to enter the detection mode; Wherein, in the user multi-tap touch behavior detection mode, within a preset response time, calculate the capacitance difference value based on the current measured holding capacitance value and the previously measured holding capacitance value, and when the capacitance difference values obtained from at least two consecutive measurements both reach the preset first threshold, determine that the user has a multi-tap touch behavior and output a response signal.

12. A pressure-sensing and click-fusion sensing method for a capacitive stylus, which is based on the pressure-sensing and click-fusion sensing system for a capacitive stylus described in claim 1, characterized in that, Including the following steps: Based on the comparison between the capacitance value output by the second detection channel and the calibrated holding detection threshold C0, perform holding behavior detection. When a holding behavior is detected, start the pen tip pressure stress detection and the click trigger detection of the pen body: The pen tip pressure stress detection includes: Based on the force applied by the user holding the capacitive stylus when writing on the writing medium surface, the pen tip part (20) retracts inward toward the pen body (10), and the crankshaft (30) moves synchronously; Based on the change in the plate spacing between the first electrode plate (101) and the second electrode plate (102) caused by the movement of the crankshaft (30), obtain the capacitance values at different plate spacings detected and output by the first detection channel of the capacitance measurement unit (200); and According to the capacitance values at different plate spacings detected and output by the first detection channel, obtain the pen tip stress corresponding to the plate spacing; The click trigger detection includes: Within a preset response time, obtain the current holding capacitance value detected and output by the second detection channel of the capacitance measurement unit (200) and the previously measured holding capacitance value, calculate the capacitance difference value, and judge whether the capacitance difference values obtained from at least two consecutive measurements both reach the preset first threshold. If so, determine that the user has a multi-tap touch behavior and output a response signal, otherwise continue to perform capacitance detection and judgment.

13. The pressure-sensing and click-fusion sensing method for a capacitive stylus according to claim 12, wherein Obtaining the nib stress corresponding to the plate spacing based on the capacitance values at different plate spacings detected and output by the first detection channel includes: The processor system (300) is configured to obtain the nib stress in the following manner: σ = E * d σ = E * (kε0A) / C Among them, σ represents the nib stress, and d σ represents the plate distance between the first plate (101) and the second plate (102) under the loaded state; E represents the Young's modulus of the elastic limit mechanism (50), A represents the plate area of the first plate (101) and the second plate (102), k represents the relative permittivity, ε0 represents the vacuum permittivity, and C represents the capacitance value output by the first detection channel of the capacitance measurement unit (200).

14. The pressure-sensing and click-fusion sensing method for a capacitive stylus according to claim 12, characterized in that, The holding detection threshold C0 calibrated for the capacitive stylus is preconfigured as follows: When the capacitive stylus is first enabled, obtain the capacitance value C before holding pre ; Based on the first gripping behavior, the capacitance value C after gripping is obtained afta ; And Set the holding detection threshold C0 = (C pre + C afta ) / 2.

15. The pressure-sensitive - click fusion sensing method for a capacitive stylus according to claim 12, wherein The holding detection threshold C0 calibrated for the capacitive stylus is preconfigured as follows: When the capacitive stylus is first enabled, obtain the capacitance value C before grasping pre ; Based on the first grasping behavior, the capacitance value C after grasping is obtained afta ; And Set the holding detection threshold C0 = k*(C pre + C afta ) / 2, where k represents the compensation coefficient and the initial value of k is 1.

16. The pressure-sensing and click-fusion sensing method for a capacitive stylus according to claim 12, wherein The step of performing the holding behavior detection by comparing the capacitance value output based on the second detection channel with the calibrated holding detection threshold C0 specifically includes: Obtaining the calibrated holding detection threshold C0; Comparing the holding capacitance value output through the second detection channel with the holding detection threshold C0: When the holding capacitance value is greater than or equal to the holding detection threshold C0, it is determined that there is a holding behavior; otherwise, it is determined that there is no holding behavior.

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