KR101459535B1 - Electronic pen having writing pressure detection function - Google Patents

Abstract

The present invention relates to an electronic pen, which is configured to allow a tablet to detect a position, where an acting electromagnetic force is released, in a pen detection area by resonating against the electromagnetic force (external electromagnetic force) released from the tablet to store energy, and by releasing the electromagnetic force (acting electromagnetic force) itself by the stored energy. The electronic pen includes an inductor (L) and a capacitor (C) forming a resonant circuit, a pen point positioned in the front of the electronic pen to be movable by a pen pressure acting when touching the pen detection area of the tablet, a plurality of pen pressure detection capacitors forming pen pressure detection capacitors (ΔC), respectively, and a conductive rubber digitally connecting the pen pressure detection capacitors to the resonant circuit by a structure changed according to the movement of the pen point. Therefore, a pen pressure on the tablet can be detected in a discrete digital method.

Description

ELECTRONIC PEN HAVING WRITING PRESSURE DETECTION FUNCTION

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electronic pen having a pressure sensing function, and more particularly, to an electronic pen configured to digitally sense pressure applied to a tablet.

2. Description of the Related Art Recently, a device for inputting a handwriting of a user by making a handwriting on a predetermined plane (for example, a pen sensing area of a tablet) using a pen-shaped tool (for example, an electronic pen) .

In addition, electronic pens capable of operating wirelessly without a built-in battery or the like have been developed so that the portable pen and the like used by the user can be reduced in portability and weight and can be utilized freely with respect to the tablet.

1 is a view for explaining the operation principle of a conventional tablet and an electronic pen operating in an electromagnetic induction manner. 1 (a) shows a coil drive driver 20 and a loop coil 30 as only a part of a tablet, and an example of the electronic pen 100 is a writing instrument having a built-in resonance circuit composed of a capacitor and an inductor Respectively.

When the coil drive driver 20 is provided with a switching pattern having a predetermined frequency (that is, a resonance frequency of the resonance circuit of the electronic pen) under the control of an MCU (not shown) of the tablet or the like, To the loop coil (30).

The loop coil 30 has a predetermined inductance and emits an induced electromagnetic force (external electromagnetic force 1) by an input AC voltage.

On the other hand, in the resonance circuit of the electronic pen 100, resonance is caused by the externally applied electromagnetic force to generate an induced current, and the generated induced current is stored in the inductor and the capacitor. When the emission of the external electromagnetic force is stopped, the resonance circuit resonates by self-stored energy (induced current) to emit an induced electromagnetic force (acting electromagnetic force 2).

On the other hand, in the tablet, the inner space of the loop coil 30 constitutes the pen sensing area A. In the pen sensing area A, although not shown, various types of electromagnetic force sensing means can be arranged. As the electromagnetic force sensing means, for example, a line antenna structure which can refer to the patent document 10-984036 can be used.

On the other hand, when the electromagnetic pen 100 itself emits an electromagnetic force (acting electromagnetic force), the pen sensing area A of the tablet senses the electromagnetic force acting on the electronic pen, Sensing position) is measured, and it is regarded that the user intends to input an operation using the electronic pen 100 to the measured coordinates.

1 (b) is a view showing a waveform of an external electromagnetic force emitted from the loop coil. When the AC drive voltage is output from the coil drive driver 20 to the loop coil 30 according to the switching pattern, an external electromagnetic force gradually rising due to the inductance existing in the loop coil 30 is emitted. The external electromagnetic force is released at the same specific intensity after a lapse of a predetermined time. If the switching pattern is interrupted by the control of the MCU at a predetermined time (for example, at time B) and the AC voltage is interrupted, It stops.

Fig. 1 (c) is a view showing the waveform of the working electromagnetic force output from the resonance circuit of the electronic pen. The resonance circuit can temporarily store the energy due to the induced current generated by the external electromagnetic force. When the emission of the external electromagnetic force is stopped, the resonance circuit resonates by self-stored energy to emit the working electromagnetic force. The working electromagnetic force is reduced by the consumption of stored energy.

의 식에 의해 결정된다. At this time, the acting electromagnetic force has the frequency fo. The frequency f0 can be determined by the capacitance and the inductance included in the resonance circuit of the electronic pen 100. [ In other words,

. ≪ / RTI >

On the other hand, since the frequency of the external electromagnetic force and the resonance frequency of the resonance circuit coincide with each other or a multiple thereof causes the most efficient resonance, the frequency of the AC voltage output from the coil drive driver 20 (that is, the frequency of the switching pattern output from the MCU ) Is also preferably f0.

Fig. 2 is a view for explaining a method of changing the resonance frequency of the resonance circuit of the electronic pen. Fig. The resonant circuit may be formed by forming at least one inductor L and at least one capacitor C in a loop.

로 표시할 수 있다. 또한, 작용 전자기력의 주기(To)는

로 나타낼 수 있다.2 (a) shows a resonant circuit formed by connecting one inductor having an inductance L and one capacitor having a capacitance C. In Fig. The resonant frequency (f0) of the working electromagnetic force emitted from this basic resonant circuit is

As shown in FIG. Further, the period To of the working electromagnetic force

.

로 산출할 수 있다. 2 (b) shows a circuit in which a capacitance-detecting capacitor (? C) capable of changing capacitance is added to the basic resonance circuit of Fig. 2 (a)

.

로 된다.Fig. 2 (c) shows a circuit in which the inductor (? L) for detecting a pressure change is added to the resonance circuit of Fig. 2 (a)

.

로 공진 주파수를 결정할 수 있다. In Fig. 2 (d), a capacitor for detecting the pressure of the pressure and an inductor for sensing the pressure are simultaneously added. In this case,

The resonance frequency can be determined.

Therefore, by mechanically connecting the pen tip with which the electronic pen 100 is brought into contact with the pen sensing area A of the tablet and the inductor for detecting the pressure and / or the capacitor for sensing the pressure, the user can press the electronic pen against the tablet The inductance and / or the capacitance of the electronic pen 100 can be measured and the amount of change of the inductance and / or the capacitance of the tablet can be measured so that the user can measure the pressure indicating the degree of pressing the electronic pen 100 against the tablet.

Fig. 3 is a diagram showing how the resonance frequency of the working electromagnetic force emitted from the electronic pen changes due to a change in inductance and / or capacitance included in the resonance circuit of the electronic pen. Referring to the drawing, when no pressure is applied to the electronic pen, an electromagnetic force having a fundamental resonance frequency fo is outputted. However, since the inductance and / or the capacitance of the resonance circuit are changed by the action of the pressure, .

The tablet senses the period T of the actuation electromagnetic force thus output and compares the sensed period T with the basic period To to calculate the amount of change in inductance and / or capacitance to measure the pressure.

Fig. 4 is a view showing an example of the configuration of the electronic pen.

4 (a) shows an example in which a pressure sensor whose capacitance changes according to the pressure acting on the electronic pen is applied. The illustrated coil 110 is for forming an inductor resonated by an external electromagnetic force and is formed around a ferrite core 112 in the form of a tube. A pen tip 105 protruding forward of the electronic pen is inserted and inserted into the ferrite core 112 and a pressure sensor 114 is disposed behind the pen tip 105. Thereby, when the user presses the electronic pen against the tablet, the pen tip 105 is pressed backward, and the pen tip 105 presses the pressure sensor 114 so that the pressure can be sensed. The pen tip 105 and the ferrite core 112 may move integrally within the ferrite core 112. However, the pen tip 105 and the ferrite core 112 may operate integrally.

4 (b) is a diagram showing an example in which a pressure acting on the electronic pen is sensed by a change in inductance. The coil 110 is formed around the bobbin 113, A movable ferrite core 112 is disposed in accordance with the depression of the pen tip 105. [ In this configuration, since the inductance changes according to the movement of the ferrite core 112, the pressure is sensed by using the inductance.

However, the above-described conventional electronic pen has a disadvantage in that an expensive pressure sensor must be used, and it is difficult to precisely measure the changing capacitance or inductance.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to provide an electronic pen configured to digitally sense a pressure applied to a tablet.

It is another object of the present invention to provide an electronic pen configured to sense a pressure of a contact with a tablet in a digital manner and an analog manner.

In order to achieve the above object, the present invention provides a tablet according to an embodiment of the present invention, which resonates with electromagnetic force (external electromagnetic force) emitted from the tablet, stores energy, and emits an electromagnetic force (acting electromagnetic force) An electronic pen configured to sense a discharge position of the working electromagnetic force in a pen sensing area includes an inductor (L) and a capacitor (C) for forming a resonant circuit, a capacitor (C) positioned in front of the electronic pen, A plurality of pressure-sensing capacitors for respectively forming a pen tip movable by a pressure acting upon contact with the sensing area and a capacitor (? C) for sensing the pressure, and a plurality of pressure-sensing capacitors And a conductive rubber for digitally connecting the sensing capacitors to the resonant circuit.

The plurality of voltage-sensing capacitors? C can be formed by using a parasitic capacitance due to electrodes formed on both surfaces of the flexible substrate to form a capacitor?

The flexible substrate includes two left and right regions where a plurality of electrodes are formed on one surface and one electrode is formed on the opposite surface to correspond to a plurality of electrodes and a common electrode is disposed at the center, And a central region in which a plurality of electrodes to be connected to the common electrode by the rubber are disposed.

The conductive rubber may have a round shape protruding toward a plurality of contact electrodes of the flexible substrate, and a plurality of contact electrodes of the flexible substrate may be formed in a vertically flat shape in a direction toward the conductive rubber.

The plurality of contact electrodes may have a plurality of electrodes arranged spirally around a common electrode.

The plurality of capacitive sensing capacitors may further include a capacitive sensing capacitor (? C) obtained by mounting at least one capacitive component in addition to a capacitive sensing capacitor (? C) formed by using a parasitic capacitance.

(External electromagnetic force) emitted from the tablet according to an embodiment of the present invention, and stores the energy by itself to emit an electromagnetic force (acting electromagnetic force) by the stored energy, so that the tablet can perform the action An electronic pen configured to sense an emission position of an electromagnetic force includes an inductor (L) and a capacitor (C) for forming a resonance circuit, and a capacitor (C) disposed in front of the electronic pen, A plurality of pressure-sensing capacitors for respectively forming a pen tip movable by a pressure and a capacitor for sensing a pressure? C; and a plurality of pressure-sensing capacitors connected to the resonance circuit by a structure varying with movement of the pen- A conductive rubber which is connected in a digital manner, and a heater which can change the inductance for sensing the pressure according to the movement of the pen tip By providing netik body, it is possible to achieve the above object.

The magnetic body may be made of a ferrite core or a magnetic metal sheet.

The magnetic metal sheet may be formed by punching after mixing metal powder with a roller.

With the above-described configuration, the present invention can digitally sense pressure applied to the tablet.

In addition, the present invention can detect the pressure of the tablet in contact with the tablet by a digital method and an analog method, thereby securing a certain degree of continuity with a discrete digital change.

1 is a view for explaining the operation principle of a conventional tablet and an electronic pen operating in an electromagnetic induction manner.
2 is a view for explaining a method of changing the resonance frequency of the resonance circuit included in the electronic pen.
Fig. 3 is a view showing a changing form of the resonance frequency of the electromagnetic force of the electromagnetic force emitted from the electronic pen due to a change in inductance and / or capacitance included in the resonance circuit of the electronic pen.
Fig. 4 is a view showing a schematic configuration example of the electronic pen. Fig.
5 is a view for explaining the principle and construction of an electronic pen having a function of detecting a pressure according to a first embodiment of the present invention.
6 is a view for explaining an example of a different implementation of the capacitor for detecting the pressure of the pattern associated with the digital pressure sensing of FIG.
7 is a view showing an example of the arrangement of a plurality of electrodes in contact with the conductive rubber of FIG.
FIG. 8 is a view for explaining another example of the implementation of the capacitor for detecting the pressure of the pattern associated with the digital pressure sensing of FIG.
9 is a view for explaining the principle and configuration of an electronic pen having a function of detecting a pressure according to a second embodiment of the present invention.
FIG. 10 is a graph showing a change in resonance frequency according to the digital pressure sensing and the analog pressure sensing shown in FIG.
FIG. 11 is a view showing an actual implementation example when only the pen tip is moved in FIG.
FIG. 12 is a view showing an actual implementation example in which the pen tip and the ferrite core move simultaneously in FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of an electronic pen having a pressure sensing function according to the present invention will be described with reference to the accompanying drawings. In the following description of the present invention, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the technical scope of the present invention. Will be.

5 is a view for explaining the principle and construction of an electronic pen having a function of detecting a pressure according to a first embodiment of the present invention.

5 is a view for explaining the principle and construction of an electronic pen having a function of detecting a pressure according to a first embodiment of the present invention. 5 (a) is a view for explaining the principle of sensing a pressure in an electronic pen, in which a plurality (in this example, four) of resonance circuits implemented in the form of a loop using an inductor and a capacitor And the capacitors (ΔC1, ΔC2, ΔC3, ΔC4) for detecting the pressure are added through the switches. According to such a circuit configuration, it is possible to predict that the capacitance of the entire resonance circuit will change according to the operation of each switch. Further, if the operation of each of the switches can be controlled according to the pressure, it can be predicted that the pressure can be measured step by step in accordance with the addition of the capacitors for sensing the pressure.

5 (b) is a view showing only important parts in a form in which the circuit as shown in Fig. 5 (a) is implemented in an electronic pen, Fig. 5 Fig.

The pen tip 505 is disposed to face the front of the electronic pen, and the ferrite core 512, which forms an inductor, is connected to the pen tip 505. On the other hand, a convex conductive rubber 520 is provided on the rear side of the ferrite core 512.

On the other hand, in the vicinity of the conductive rubber 520, a plurality of voltage-sensing capacitors? C1,? C2,? C3,? C4 for digitally changing the capacitance to change the resonance frequency and a PCB 540 Are in contact with or close to each other.

At this time, the pen tip 505, the ferrite core 512, and the conductive rubber 520 are integrally configured to be movable back and forth in the body of the electronic pen (not shown), and the PCB 540 is fixed to the body of the electronic pen . The surface of the PCB 540 facing the conductive rubber 520 constitutes a contact portion 542 to be brought into contact with the conductive rubber 520.

Further, conductors (contact electrodes 551 and 552) extending from a plurality of capacitive sensing capacitors are exposed toward the conductive rubber 520 at the contact portion 542. [

When the user touches the tablet with the electronic pen having such a configuration, a pressure due to the pressure acting on the pen tip 505 acts on the ferrite core 512 to bring the conductive rubber 520 into contact with the PCB 540, The conductive rubber 520 is pressed against the contact portion 542 of the PCB 540 and the conductive rubber 520 is pressed against the PCB 540 in accordance with the collapse, The contact area with the contact portion 542 becomes wider.

If the contact electrodes of the capacitor-sensing capacitors? C are arranged so as to be sequentially connected to the conductive rubber according to the width of the contact surface, the capacitive sensing capacitor is sequentially applied to the resonance circuit in accordance with the pressure acting on the conductive rubber 520 Can be connected.

A common electrode 551 and contact electrodes 552 extending from the respective capacitive sensing capacitors? C1,? C2,? C3 and? C4 are formed on the contact portion 542 of the PCB 540 sequentially from the common electrode 551 Respectively. The conductive rubber 520 shown by the dotted line is in a state in which no pressure is applied to the electronic pen and is in slight contact with the common electrode 551. [ Of course, in this state, the conductive rubber 520 may be kept spaced apart from being in contact with neither the common electrode 551 nor the contact electrode 552.

로 변화할 것이며, 이에 의해 타블렛에서는 변화된 공진 주파수로부터 커패시턴스의 변화량을 산출하고, 필압을 인식하게 될 것이다. The conductive rubber 520 shown by the solid line shows a state in which the pressing force acts on the pen tip 505 of the electronic pen and the conductive rubber 520 is pressed against the contact portion 542 of the PCB 540. In the illustrated state, it can be seen that the contact surface of the conductive rubber 520 is formed to the contact electrodes of the two capacitive sensing capacitors? C1 and? C2 including the common electrode 551. In this state, the capacitance of the resonance circuit will be C + ΔC1 + ΔC2, and the resonance frequency

So that the tablet will calculate the amount of change in capacitance from the changed resonant frequency and will recognize the pressure.

6 is a view for explaining an example of a different implementation of the capacitor for detecting the pressure of the pattern associated with the digital pressure sensing of FIG. 6 (a) is a view for explaining the principle of a parasitic capacitor used in the present invention, FIG. 6 (b) is an example of implementing a capacitor for sensing a pressure by using a flexible substrate, 6 (d) is a diagram showing electrode arrangements on the front surface and the back surface of the flexible substrate.

6 (a), the parasitic capacitor used in the present invention can be obtained through two electrodes 620 and 630 formed on both sides of a dielectric 610 having a constant dielectric constant epsilon. The lower electrode 620 is entirely covered with the electrode while the dielectric 610 having the thickness d and the thickness d is sandwiched therebetween and the upper electrode 630 has only a constant area A, The expected capacitance is as follows.

C =? * A / d

6 (b) shows a case in which a capacitor for sensing the pressure is implemented according to the principle of FIG. 6 (a) using a flexible substrate, and the front and back surfaces of the flexible substrate are shown in FIGS. 6 ).

As shown in Fig. 6 (b), the flexible substrate 650 is used as the dielectric 610 in this example. The flexible substrate has a plurality of electrodes 660 formed on the front surface thereof, a left and right region where one electrode 670 is formed in a size corresponding to the plurality of electrodes on the back surface, Includes a central region in which contact regions (662) of a plurality of contact regions (660) are disposed.

6 (c), a plurality of electrodes 660 are disposed on both sides of the front surface of the flexible substrate 650, and a plurality of electrodes 660 are staggered.

6 (d), one electrode 670 is formed in the left and right regions of the rear surface of the flexible substrate 650, respectively, in a size corresponding to the plurality of electrodes 660 on the front surface. The back surface of the flexible substrate 650 is provided with a common electrode terminal 682 for connecting the common electrode 680 on the front surface to the PCB on which the capacitor is mounted.

7 is a view showing an example of the arrangement of a plurality of electrodes in contact with the conductive rubber of FIG.

7A shows a case where a conductive rubber is flat and the electrode surface on which the contact regions 662 of the plurality of electrodes 660 are disposed is designed as a curved surface. The contact regions 662 of the electrodes 660 are arranged in a staggered pattern.

7B is a plan view of the electrode surface on which the conductive rubber is convex and the contact areas 662 of the plurality of electrodes 660 are disposed. The electrodes are arranged in a spiral pattern. In the case of the helical structure pattern of FIG. 7 (b), the change of the digital value according to the pressure can be obtained more linearly.

FIG. 8 is a view for explaining another example of the implementation of the capacitor for detecting the pressure of the pattern associated with the digital pressure sensing of FIG.

In FIG. 6, a capacitor for sensing the pressure is implemented using a parasitic capacitor of a flexible substrate, but in some cases, a large capacitance change may be required. In this case, since it is difficult to realize a large capacitance change with only the parasitic capacitor inside, a general capacitor component 810 is mounted so that a minute change makes use of a change in parasitic capacitance, and a large change is caused by a change in the capacitance of the capacitor component 810 Change is available.

8 (a) and 8 (b) are diagrams showing electrode arrangements on the front surface and the back surface of a flexible substrate on which capacitor components are further mounted.

8A, a plurality of electrodes 660 are disposed on both sides of the flexible substrate 650, and a capacitor component 810 is mounted on the flexible substrate 650. In the central region, The contact regions 662 of the plurality of electrodes 660 are staggered around the center electrode 680.

As shown in FIG. 8 (b), one electrode 670 is formed in the right and left regions of the rear surface of the flexible substrate 650, respectively, to correspond to the plurality of electrodes 660 on the front surface. The back surface of the flexible substrate 650 is provided with a common electrode terminal 682 for connecting the common electrode 680 on the front surface to the PCB on which the capacitor is mounted.

Fig. 8 (c) is a diagram showing the electrode arrangement shown in Fig. 8 (a) and Fig. 8 (b) by an electric circuit.

The capacitor components 810 and the parasitic capacitors 820 are connected to the resonant circuit when the switching region 830 is in contact with the conductive rubber 690. The terminal 812 corresponds to the terminal 812 shown in Fig. 8 (a), and the terminal 670 corresponds to the electrode 670 shown in Fig. 8 (b). The terminal 682 corresponds to the electrode 682 shown in Fig. 8 (b). This allows the conductive rubber 690 to change the resonance frequency by connecting the capacitor components 810 and the parasitic capacitors 820 sequentially to the terminal 682 through the switching region 830 by the pressure.

On the other hand, in FIG. 8, capacitor components are mounted on the front surface, but such mounting components may use not only capacitor components but also inductor components.

9 is a view for explaining the principle and configuration of an electronic pen having a function of detecting a pressure according to a second embodiment of the present invention.

9 (a) is a view for explaining the principle of sensing the pressure in the electronic pen according to the second embodiment of the present invention. In addition to the inductor L and the capacitor L constituting the resonance circuit, C1, C2, C3, and C4 which can be connected in parallel to the capacitor C. The inductor L is connected in series to the inductor LL. 9 (a), the inductor L and the inductor L for sensing the pressure are shown separately, but the inductor L for sensing the pressure may be a change in inductance in the inductor L. FIG. The capacitance change of the capacitive sensing capacitors? C1,? C2,? C3, and? C4 is the same as that of the first embodiment described above, and thus description thereof is omitted.

Fig. 9 (b) is a view for simply explaining the principle of the inductor L for detecting the pressure of pressure shown in Fig. 9 (a).

When the ferrite core 910 wound on the coil 912 is pushed backward by the pressure to approach the magnetic body 920, the inductor L for the pressure sensing is increased as shown in the right graph. Since the distance between the ferrite core and the magnetic body varies depending on the movement of the ferrite core caused by the pressure, the inductance of the inductor L for detecting the pressure of the pressure changes.

Fig. 9 (c) is an example of actual implementation of the resonance circuit shown in Fig. 9 (a).

9 (c), the electronic pen includes a pen tip 930, a ferrite core 910, a conductive rubber 940, a flexible substrate 950, a magnetic body 920, and a PCB 960 .

The pen tip 930 is positioned in front of the electronic pen to enable writing on the tablet and can move backward by a pressure that acts when touching the pen sensing area of the tablet.

A coil 912 is wound around the ferrite core 910 to constitute an inductor L resonated by an external electromagnetic force.

The conductive rubber 940 has a structure capable of being elastically collapsed by the pressure acting on the pen tip 910. The conductive rubber 940 may be rounded to protrude toward the plurality of contact electrodes of the flexible substrate 950.

The flexible substrate 950 is formed with a plurality of capacitors for sensing the pressure to form the capacitors C for sensing the pressure by using the parasitic capacitance shown in FIG. Further, the flexible substrate 950 may have capacitor components mounted thereon for a large change in capacitance. The plurality of electrodes disposed on the flexible substrate 950 are brought into contact with the PCB 60 via the common electrode terminal 682.

The magnetic body 920 is provided on the back surface of the flexible substrate 950 and can also serve as a PCB fixing housing. The magnetic body 920 may be made of a ferrite core or a magnetic metal sheet. The magnetic metal sheet can be simply formed by punching after mixing the metal powder with a roller. When the magnetic body 920 is used as a magnetic metal sheet rather than a ferrite core, it is possible to reduce the cost and facilitate the fixing.

The PCB 960 is mounted with capacitors and other electronic components constituting a resonant circuit.

9, as the pressure acting on the pen tip 930 increases, the plurality of electrodes disposed on the flexible substrate 950 are more connected by the conductive rubber 940, so that the capacitance increases and the ferrite core 910 The inductance increases due to the reduction of the distance between the magnet body 920.

FIG. 10 is a graph showing a change in resonance frequency according to the digital pressure sensing and the analog pressure sensing shown in FIG.

10 (a) is a diagram showing a change in the capacitance of the capacitors for sensing the pressure of the pressure related to the digital pressure sensing function according to the pressure.

10 (b) is a diagram showing a change in inductance associated with the detection of the pressure of the pressure according to the pressure. As described above, the inductance increases analogously when the ferrite core 910 and the magnetic body 920 are brought close to each other.

10 (c) is a view showing a change in the resonance frequency according to the pressure when the digital pressure detection of Fig. 10 (a) and the analog pressure detection of Fig. 10 (b) are provided. As can be seen from FIG. 10 (c), there is an advantage that the change of the resonance frequency according to the pressure is sharp at the beginning, while the remaining portion has a certain change with continuity to the digital change to some extent.

FIG. 11 is a view showing an actual implementation example when only the pen tip is moved in FIG.

Fig. 11 (a) shows an embodiment in which the conductive rubber is convex, and Fig. 11 (b) shows an embodiment in which the conductive rubber is a flat plate.

The pen tip 930 is positioned in front of the electronic pen to enable writing on the tablet and can move backward by a pressure that acts when touching the pen sensing area of the tablet.

A coil 912 is wound around the ferrite core 910 to constitute an inductor L resonated by an external electromagnetic force. Inside the ferrite core 910, a space through which the pen tip 930 can move is provided.

The conductive rubber 940 has a structure capable of being elastically collapsed by the pressure acting on the pen tip 910. 11A shows the conductive rubber 940 in a round shape protruding toward a plurality of contact electrodes of the flexible substrate 950. In FIG 11B, the conductive rubber 940 is shown as a flat plate .

Between the ferrite core 910 and the conductive rubber 940, a connector 960 is further provided for connecting the ferrite core 910 and the conductive rubber 940 to each other.

The flexible substrate 950 is formed with a plurality of capacitors for sensing the pressure to form the capacitors? C for detecting the pressure by using the parasitic capacitance. Further, the flexible substrate 950 may have capacitor components mounted thereon for a large change in capacitance. 11 (a), a central region of the flexible substrate 950 to which the conductive rubber contacts is curved. In FIG. 11 (b), the central region of the flexible substrate 950 to which the conductive rubber contacts is formed in a plane have.

A magnetic body 920 is provided on the back surface of the flexible substrate 950. 9, a housing case 980 for fixing the magnetic body 920 to the PCB 960 is further provided.

The PCB 960 is mounted with capacitors and other electronic components constituting a resonant circuit.

FIG. 12 is a view showing an actual implementation example in which the pen tip and the ferrite core move simultaneously in FIG.

Fig. 12 (a) shows an embodiment in which the conductive rubber is convex, and Fig. 12 (b) shows an embodiment in the case where the conductive rubber is a flat plate.

The pen tip 930 is positioned in front of the electronic pen to enable writing on the tablet and can move backward by a pressure that acts when touching the pen sensing area of the tablet.

A coil 912 is wound around the ferrite core 910 to constitute an inductor L resonated by an external electromagnetic force. The ferrite core 910 moves with the pen tip 930

The conductive rubber 940 has a structure capable of being elastically collapsed by the pressure acting on the pen tip 910. 12 (a) shows a conductive rubber 940 in a round shape protruding toward a plurality of contact electrodes of a flexible substrate 950, whereas a conductive rubber 940 is shown as a flat plate in FIG. 12 (b) .

The flexible substrate 950 is formed with a plurality of capacitors for sensing the pressure to form the capacitors? C for detecting the pressure by using the parasitic capacitance. Further, the flexible substrate 950 may have capacitor components mounted thereon for a large change in capacitance. 12 (a), a central region of the flexible substrate 950 to which the conductive rubber contacts is curved. In FIG. 12 (b), the central region of the flexible substrate 950 to which the conductive rubber contacts is formed in a plane have.

A magnetic body 920 is provided on the back surface of the flexible substrate 950. Further, a housing case 980 for fixing the magnetic body 920 to the PCB 960 is further provided.

The PCB 960 is mounted with capacitors and other electronic components constituting a resonant circuit.

The embodiments of the present invention described above are merely illustrative of the technical idea of the present invention, and the scope of protection of the present invention should be interpreted according to the claims. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It should be interpreted that it is included in the scope of right.

505: Pen tip 512: Ferrite core
520: conductive rubber 540: PCB
650: flexible substrate 660: a plurality of electrodes
670: one electrode 680: common electrode
690: Conductive rubber 910: Ferrite core
920: Magnetic body 930: Pen tip
940: conductive rubber 950: flexible substrate
960: PCB

Claims (10)

(External electromagnetic force) emitted from the tablet, stores energy, and emits an electromagnetic force (acting electromagnetic force) by itself by the stored energy so that the tablet can sense the position of emission of the working electromagnetic force within the pen sensing area Wherein the electronic pen comprises:
An inductor L and a capacitor C for forming a resonance circuit,
A pen tip that is positioned in front of the electronic pen and is movable by a pressure applied when the pen touches the pen sensing area of the tablet;
A plurality of pressure sensing capacitors each forming a capacitor? C for detecting the pressure,
And a conductive rubber for digitally connecting the plurality of pressure sensing capacitors to the resonant circuit by a structure that varies according to the movement of the pen tip. The method according to claim 1,
Wherein the plurality of voltage-sensing capacitors (? C) form a capacitor (? C) for sensing a voltage by using a parasitic capacitance caused by electrodes formed on both surfaces of the flexible substrate. 3. The method of claim 2,
The flexible substrate may include:
A plurality of electrodes formed on one surface, two left and right regions formed on the opposite surface, each electrode having a size corresponding to the plurality of electrodes,
And a central region in which a common electrode is disposed in the center and an area where a plurality of electrodes to be connected to the common electrode by the conductive rubber are disposed is disposed around the central region. The method of claim 3,
Wherein the conductive rubber has a round shape protruding toward a plurality of contact electrodes of the flexible substrate,
Wherein the plurality of contact electrodes of the flexible substrate are formed in a vertically flat shape in a direction toward the conductive rubber. 5. The method of claim 4,
Wherein the plurality of contact electrodes have a plurality of electrodes arranged spirally around a common electrode. The method according to any one of claims 2 to 5,
Wherein the plurality of voltage sensing capacitors further include a capacitive sensing capacitor (? C) obtained by mounting at least one capacitor component in addition to a capacitive sensing capacitor (? C) formed by using a parasitic capacitance. (External electromagnetic force) emitted from the tablet, stores energy, and emits an electromagnetic force (acting electromagnetic force) by itself by the stored energy so that the tablet can sense the position of emission of the working electromagnetic force within the pen sensing area Wherein the electronic pen comprises:
An inductor L and a capacitor C for forming a resonance circuit,
A pen tip that is positioned in front of the electronic pen and is movable by a pressure applied when the pen touches the pen sensing area of the tablet;
A plurality of pressure sensing capacitors each forming a capacitor? C for detecting the pressure,
A conductive rubber that digitally connects the plurality of pressure sensitive capacitors to the resonant circuit by a structure that varies according to the movement of the pen tip;
And a magnetic body capable of changing the inductance for sensing the pressure according to the movement of the pen tip. 8. The method of claim 7,
Wherein the plurality of voltage-sensing capacitors (? C) form a capacitor (? C) for sensing a voltage by using a parasitic capacitance caused by electrodes formed on both surfaces of the flexible substrate. 9. The method of claim 8,
Wherein the magnetic body is made of a ferrite core or a magnetic metal sheet. 10. The method of claim 9,
Wherein the magnetic metal sheet is formed by punching after mixing the metal powder with a roller.

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