JP2019128752A - Electronic pen - Google Patents

Abstract

To provide an electronic pen capable of replacing in a timely manner when it is time to replace a core body.SOLUTION: An electronic pen is provided so that a tip end portion of a core body protrudes from an opening in an axial direction of main body housing, and the core body is detachable from the main body housing. The electronic pen includes a cap portion that is detachably coupled to the main body housing in the axial direction. Further, the main body housing includes a core body holding portion capable of holding one or a plurality of core bodies on a side opposite to the opening side in the axial direction. A cap portion includes a core-extracted portion used to pull the core body out of the main body housing. The one or the plurality of core bodies held by the core body holding portion are exposed when using the core-extracting part to pull out and remove the core body protruding from the opening in the axial direction of the main body housing.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electronic pen which is used together with a position detection device and whose core is replaceable.

  In the electronic pen, since signals are exchanged with the tablet through interaction by inductive coupling and electrostatic coupling, the core does not decrease and the ink does not disappear as in the case of a writing instrument of ordinary stationery. However, since the tip of the core (pen tip) is also used in contact with the tablet in an electronic pen, the tip of the core is gradually worn away by friction with the tablet.

  Therefore, there are many electronic pens that can exchange the core (see, for example, Patent Document 1 (Japanese Patent No. 6137610) and Patent Document 2 (Japanese Patent No. 5801020)). In this type of electronic pen, generally, a writing pressure detection unit is provided in a casing, and a rod-shaped core is detachably fitted to and attached to the writing pressure detection unit. Further, the core body may be attached by being detachably fitted to a pressure transmission unit fitted to the writing pressure detection unit.

Japanese Patent No. 6137610 Japanese Patent No. 5801020

  By the way, in order to replace the core of the electronic pen, it is necessary to pull out the core from the housing of the electronic pen. However, in the electronic pen of this type, generally, the core body is fitted to the writing pressure detection unit or the pressure transmission unit disposed in the housing so as not to drop out of the housing, and the housing From this point, only the tip of the core body is slightly protruded.

  Therefore, it is troublesome for the user to pinch the tip of the core with a finger and pull the core from the housing. Therefore, when replacing the core of the electronic pen, there is also a type that includes a core removal tool for pulling out the core from the housing of the electronic pen as a separate body from the electronic pen.

  However, since the centering tool is separate from the electronic pen, it may be lost or may not be at hand when actually replacing the core, which is inconvenient. Yes.

  Furthermore, since the spare core to be replaced is a separate one like the coring tool, it is easy to lose it, and when replacing the core, it may not be at hand, which is inconvenient. It has become.

  An object of the present invention is to provide an electronic pen which can solve the above problems.

In order to solve the above problems,
An electronic pen in which the tip of the core body protrudes from the opening in the axial direction of the main body housing, and the core body is detachably attached to the main body housing,
And a cap unit detachably coupled to the main unit casing in the axial direction,
The main body housing includes a core body holding portion capable of holding one or a plurality of core bodies on a side opposite to the opening side in the axial direction.
The cap portion includes a centering portion that is used to pull out the core body from the main body housing and remove it.
The one or more held by the core body holding portion when the core portion is used to pull out and remove the core body protruding from the axial opening of the main body casing. An electronic pen characterized in that a core of a book is exposed.

  According to the electronic pen having the above-described configuration, the cap portion detachably coupled to the main body housing portion of the electronic pen includes the centering portion, so when it is time to replace the core body, the core of the cap portion Since the core body is pulled out from the housing using the punched portion and the replacement core body is exposed, it is very convenient.

It is a figure for demonstrating an example of the tablet used with embodiment of the electronic pen by this invention, and the embodiment of the said electronic pen. It is a figure for demonstrating the structural example of embodiment of the electronic pen by this invention. It is a figure for describing the embodiment of the electronic pen by this invention. It is a figure for demonstrating the example of the centering part of embodiment of the electronic pen by this invention. It is a figure which shows an example of the core body holding part of embodiment of the electronic pen by this invention. It is a figure for demonstrating the main-body part of embodiment of the electronic pen by this invention. It is a figure for demonstrating the exchange operation of the core body in embodiment of the electronic pen by this invention. It is a figure for demonstrating the modification of the centering part of embodiment of the electronic pen by this invention. It is a figure for demonstrating the example of the core-removing part of other embodiment of the electronic pen by this invention. It is a figure for describing other embodiment of the electronic pen by this invention.

  Hereinafter, embodiments of the electronic pen according to the present invention will be described with reference to the drawings.

  FIG. 1 is a view showing the appearance of the state where the electronic pen 1 of this embodiment is placed on a tablet 10 as a position detection device, as viewed from the surface 10 a side of the tablet 10.

  The tablet 10 in this example has a plate-like rectangular parallelepiped shape with a thin outer shape as shown in FIG. Although not shown, a position detection sensor and an electronic circuit are provided inside the tablet 10. An area surrounded by a dotted line on the surface 10a of the tablet 10 in FIG. 1 is a coordinate detection area 11 in which the coordinates of the indicated position by the electronic pen 1 by the position detection sensor can be detected.

  On the surface 10 a of the tablet 10, an electronic pen placement unit 12 is formed in an upper area outside the coordinate detection area 11. When the electronic pen 1 is placed, the electronic pen placement portion 12 is shaped to be longer than the length in the axial center direction of the electronic pen 1 of this embodiment and wider than the thickness of the electronic pen 1. The dish-shaped concave portion 12a is configured so as not to roll out from the electronic pen placement portion 12.

  An operation unit 13 that can be pressed down by a user is provided in a recess 12 a that constitutes the electronic pen placement unit 12 of the tablet 10. In this example, the operation unit 13 is divided into a plurality of operation parts (operation buttons), to which power on / off and various functions are assigned. The operation unit 13 can be operated when the electronic pen 1 is not placed in the recess 12 a.

  Further, in this example, an electronic pen holder 14 configured in a cylindrical shape with, for example, chemical fiber or leather is attached to the upper side surface of the tablet 10. When carrying the tablet 10, the electronic pen 1 can be inserted and held in the electronic pen holder 14.

  As shown in FIGS. 2A to 2C, the electronic pen 1 includes a main body portion 2 and a cap portion 3. The main body 2 is configured by housing an electronic pen component 22 (see FIG. 3) inside a cylindrical main body housing 21 made of, for example, resin. And the pen point side of the cylindrical main body housing 21 is tapered so that it has an opening 21a (see FIG. 4), and the tip 4a of the core body 4 extends from the opening 21a. It is comprised so that it may protrude. The tapered portion on the pen tip side of the main body housing 21 may be configured integrally with the main body housing 21 or may be configured to be coupled as a separate member.

  In this example, the tablet 10 detects a position indicated by the electronic pen 1 by an electromagnetic induction method. For this reason, the electronic pen component 22 of the electronic pen 1 of this embodiment is a resonant circuit for interacting with the tablet 10 by electromagnetic induction coupling with a plurality of loop coils provided in the sensor of the tablet 10 to exchange signals. including.

  FIG. 3 is a diagram for explaining a main part of the electronic pen component 22 of the electronic pen 1 of this embodiment. That is, the electronic pen component 22 includes a magnetic core 222 around which a coil 221 is wound, a writing pressure detection unit 223, and a printed board 224. The magnetic core 222 around which the coil 221 is wound is provided on the pen tip side of the hollow portion of the main body housing 21 as shown in FIG. The magnetic core 222 is formed of a ferrite core, for example, and includes a through hole 222a through which the core body 4 is inserted.

  The core 4 is, in this example, made of a non-conductive material such as a resin. The core body 4 passes through the through-hole 222a of the magnetic core 222 and is fitted in a detachable state to the fitting portion 223a of the writing pressure detection unit 223. In the fitted state, the core body 4 The distal end portion 4 a is in a state of projecting from the opening 21 a of the main body portion case 21. Therefore, the core body 4 can be removed from the main body housing 21 and replaced by gripping and pulling the distal end portion 4 a of the core body 4.

  The writing pressure detection unit 223 uses, for example, a mechanism that changes the capacitance of a capacitance variable capacitor in accordance with an applied pressure (writing pressure) (see, for example, Japanese Patent Application Laid-Open No. 2011-186803). Composed. The writing pressure detection unit 223 can also use a variable capacitance capacitor formed of a semiconductor chip formed of a MEMS (Micro Electro Mechanical Systems) element (see, for example, a patent document (Japanese Patent Application Laid-Open No. 2013-161307)). The configuration of the writing pressure detection unit 223 is not limited to these configuration examples, and the writing pressure may be detected as a change in inductance.

  The coil 221 is connected in parallel with the capacitor 225 disposed on the printed circuit board 224 to form a resonance circuit. In this example, the variable capacitance capacitor configured by the writing pressure detection unit 223 is also connected in parallel with the coil 221 and the capacitor 225 to form a part of the resonance circuit. The electronic pen 1 of this embodiment interacts with the tablet 10 by electromagnetically coupling with the tablet 10 by this resonance circuit and exchanging signals with each other. The tablet 10 detects the pointing position by the electronic pen 1 and the writing pressure in the electronic pen 1 by the interaction with the electronic pen 1.

  As shown in FIG. 2C, a side opposite to the pen point side of the cylindrical main body housing 21 is a cap fitting portion 211 that fits the cap portion 3. The cap fitting portion 211 is smaller in diameter than the other portions of the main body housing 21, and a ring-like protrusion 212 for locking the cap portion 3 is formed at a predetermined position in the axial direction. ing.

  The cap part 3 is comprised, for example with resin, and is provided with the recessed part 31 fitted with the cap fitting part 211 of the main-body part housing | casing 21. FIG. A ring-shaped concave groove 32 is formed at a position corresponding to the ring-shaped protrusion 212 of the cap fitting portion 211 in the concave portion 31 of the cap portion 3.

  The cap portion 3 is coupled to the main body housing 21 so as to cover the cap fitting portion 211 with the recess 31. Then, the ring-shaped concave groove 32 of the cap portion 3 and the ring-shaped protrusion 212 of the cap fitting portion 211 are fitted, and the cap portion 3 is locked to the main body housing 21. When the cap portion 3 is pulled with a predetermined force to the side opposite to the pen point side from this state, the fitting between the ring-shaped recessed groove 32 of the cap portion 3 and the ring-shaped protrusion 212 of the cap fitting portion 211 is released. The cap 3 can be removed from the main body housing 21.

  And, in the electronic pen 1 of this embodiment, as shown in FIG. 2 (B), a coring portion 33 is provided on the top of the cap 3 on the opposite side to the fitting side with the main body housing 21. It is provided in a state where it can be viewed from the outside.

  FIG. 4 shows a longitudinal sectional view of the top of the cap 3. In this embodiment, as shown in FIGS. 2B and 4, the centering portion 33 is formed on the top of the cap portion 3 from the diameter of the tip of the tapered portion on the pen tip side of the main body housing 21. A recess 331 with a larger diameter is formed, and a core engagement hole 332 with a diameter slightly larger than the diameter of the core 4 is formed in the center of the bottom of the recess 331 in the direction orthogonal to the axial direction. Consists of.

  In this embodiment, a ring-shaped protrusion 333 is formed in the core engagement hole 332 of the core removal portion 33 so as to firmly grip the distal end portion 4 a of the core body 4. The ring-shaped protrusion 333 is not essential, and is for more reliably gripping the distal end portion 4a of the core body 4. When the cap 3 is pulled in the axial direction in a state where the tip 4 a of the core 4 is press-inserted into the core engagement hole 332, the core 4 is a pen pressure detecting portion of the main body housing 21. In the case where the engagement with the H.223 is released and it can be pulled out, the ring-shaped protrusion 333 does not need to be provided.

  In this embodiment, the cap fitting portion 211 of the main body housing 21 is provided with a core body holding portion 213 for storing the replacement core 4E (see FIG. 6) of the core body 4. FIG. 5A is a view of the main unit case 21 as viewed from the side of the cap fitting portion 211 in the axial direction, and FIG. 5B is a cross-sectional view along the line A-B-C. It is.

  As shown in FIG. 5B, a concave portion 211a is formed in the cap fitting portion 211, and a core body holding portion 213 made of a sponge in this example is disposed in the concave portion 211a. In the core body holding portion 213, a replacement core storage hole 213a made of a concave hole for storing the replacement core 4E is formed in the axial direction. The diameter of the replacement core storage hole 213a is slightly smaller than the diameters of the core body 4 and the replacement core 4E. The core 4 and the replacement core 4E are held by the core holding portion 213 by being inserted into the replacement core storage hole 213a.

  In this example, three replacement core storage holes 213a are provided, but the number is not limited to three, and may be one, two, or four or more. In addition, the core body holding portion 213 is made of sponge in this example, but may be made of elastic rubber or resin.

  In this case, the length (depth) of the replacement core storage hole 213a in the axial center direction is made shorter than the length of the replacement core 4E. Thereby, as shown in FIG. 6, when the replacement core 4E is stored in the replacement core storage hole 213a, a part of the replacement core 4E protrudes to the outside, and the replacement core 4E can be easily taken out. In addition, the length (depth) of the axial direction of the recess 31 of the cap portion 3 is a recess including the projecting portion of the replacement core 4E when the replacement core 4E is stored in the replacement core storage hole 213a. 31 is selected to be large enough to be contained and covered.

  Since the electronic pen 1 of this embodiment is configured as described above, the electronic pen 1 of this embodiment is replaced by the replacement storage hole 213a of the core holding portion 213 provided in the cap fitting portion 211 of the main body portion case 21. In the state in which the core 4E is stored, the cap unit 3 is combined with the main body housing 21 so that the cap fitting unit 211 is stored in the recess 31 and used as shown in FIG. The electronic pen 1 in a state can be configured. Therefore, the replacement core 4 </ b> E can be held by the cap fitting portion 211 of the main body housing 21 of the electronic pen 1. For this reason, when exchanging the core body 4, the trouble of preparing the replacement core 4E separately becomes unnecessary, and it is convenient.

  When exchanging the core body 4, the cap portion 3 is removed from the main body housing 21, and as shown in FIG. The press-fit is inserted into the engagement hole 332 and engaged with the core removal portion 33. In this state, the core 4 is pulled out from the main body case 21 by applying a force to the main body case 21 so as to separate the cap portion 3 in the direction of the arrow AR in FIG. Can do.

  After pulling out the core body 4 from the main body portion case 21, one of the transfer cores 4 E is pulled out from the core body holding portion 213 of the cap fitting portion 211 of the main body portion case 21, and the opening 21 a of the main body portion case 21. And the end portion is fitted to the writing pressure detection unit 223. The core replacement is now complete.

  The replaced core body 4 is pulled out from the core body engaging hole 332 of the core section 33 of the cap section 3 and discarded if worn. The replacement core 4E can also be a core with various writing qualities depending on the hardness of the material, the shape of the tip, and the like. In such a case, the core is replaced in order to change the writing according to the application, but the replaced core 4 is the core holding portion in which the newly attached replacement core 4E is stored. It can be stored and held in the replacement core storage hole 213a of 213 to prepare for the replacement again. Therefore, the core 4 and the replacement core 4E to be used can be held in the electronic pen 1 without being lost.

  And according to the electronic pen 1 mentioned above, since the core removal part 33 is provided in the cap part 3, it does not need a core removal tool separately, Moreover, the cap part 3 is outside at the time of replacement | exchange operation of a core. Then, since the replacement core held by the core body holding part 213 is exposed, the core body can be replaced at a necessary appropriate timing.

[Other Embodiments or Modifications]
In the electronic pen 1 according to the above-described embodiment, the core removal unit 33 is capable of gripping the core body with a gripping force that can extract the core body from the electronic pen 1 when the core body is fitted. Although the engagement hole 332 is configured, the configuration of the centering portion is not limited to the above example. FIG. 8 shows a configuration example of another example of the centering portion 33A provided in the cap portion 3, and FIG. 8 (A) is a view of the cap portion 3 viewed from the top side in the axial direction. FIG. 8B is a longitudinal sectional view (DD sectional view of FIG. 8A) of the portion of the centering portion 33A of the cap portion 3. FIG.

  In this example, the cap part 3 is comprised by the thin member which has the hollow part 3a, as shown to FIG. 8 (B). And as shown to FIG. 8 (A) and (B), the through-hole 334 of the diameter larger than the diameter of the core 4 is in the part of the surface of the direction orthogonal to the axial center direction of the top of the cap part 3. A plurality of projecting portions that are provided so as to communicate with the hollow portion 3a and project radially from the inner wall surface of the through hole 334 toward the center position of the through hole 334 in a direction perpendicular to the axial direction. In the example, four protrusions 335a, 335b, 335c, and 335d are provided in a cross shape.

  In this case, of the four protrusions 335a, 335b, 335c, 335d, the distance between the tips of the protrusions 335a and 335c facing each other through the center position of the through hole 334, and the protrusions 335b and 335d As shown in FIG. 8B, the separation distance between the tips is set to be approximately equal to or slightly smaller than the diameter of the core body 4. The centering portion 33A in this example includes a through hole 334 and four projecting portions 335a, 335b, 335c, and 335d.

  In the example of FIG. 8, when replacing the core body 4, the tip end portion 4 a of the core body 4 is the tip end of the four projecting portions 335 a, 335 b, 335 c and 335 d of the centering portion 33 A of the cap portion 3. Plug into the space. Then, the four projecting portions 335a, 335b, 335c, and 335d of the centering portion 33A are engaged with the tip portion 4a of the core body 4 so as to grip the tip portion 4a, as shown in FIG. Similarly, the core body 4 can be pulled out from the main body housing 21 by separating the cap portion 3 from the main body housing 21.

  In the above embodiment, the centering portions 33, 33A are provided on the surface in the direction orthogonal to the axial direction of the top portion of the cap portion 3. However, the present invention is not limited to this configuration. You may provide in a side peripheral surface (surface along an axial center direction). Further, for example, as shown in FIG. 9, a clip may be provided in the cap portion, and a centering portion may be formed in the clip portion.

  That is, in the electronic pen 1B of the example of FIG. 9, the clip 34 is provided in the cap portion 3B. In this example, the cap portion 3 </ b> B itself is not provided with a centering portion, and a centering portion 35 is formed on the clip 34. Since the configuration of the electronic pen 1B of this example is the same as that of the above-described electronic pen 1 except for the cap portion 3B, the same reference numerals are given to the portions and the description thereof is omitted.

  FIG. 9A is a view of the electronic pen 1B of this example as viewed from above the clip 34 of the cap portion 3B. FIG. 9B is a view of the electronic pen 1 </ b> B of this example as viewed from the side of the clip 34. Further, FIG. 9C is a cross-sectional view taken along line EE in FIG. 9A and shows an enlarged portion of the clip 34 for explanation.

  The clip 34 in this example is an L-shaped member made of an elastic metal or synthetic resin. That is, the clip 34 has a plate-like clip main body 341 parallel to the side circumferential surface of the cap 3B along the axial direction, and the clip main body 341 for attaching the clip main body 341 to the cap 3B. And a support portion 342 orthogonal to the surface 341. In this example, the support part 342 is formed at the side peripheral surface position in the vicinity of the top part of the cap part 3B. The support portion 342 is integrally formed with the ring-shaped member 343 fixed to the cap portion 3B.

  The clip 34 is configured so that the clip body 341 is always elastically biased in the direction orthogonal to the axial direction with respect to the circumferential side surface of the cap 3B, with the position of the support 342 as a fulcrum. A bulging portion 341a is formed at the end of the clip body 341 opposite to the support portion 342 so that the clip body 341 is always separated from the side peripheral surface of the cap portion 3B by a predetermined distance. ing.

  Further, in this example, as shown in FIG. 9C, a centering portion 35 including a through hole 35a penetrating in the thickness direction of the clip main portion 341 at a predetermined position of the clip main portion 341 of the clip 34. Is formed. In this example, as shown to FIG. 9 (A), the through-hole 35a which comprises the centering part 35 is made into the shape of a triangle. The size of the triangular through hole 35 a constituting the centering portion 35 is such that the core 4 can be press-fit into the triangular through hole 35 a.

  When replacing the core 4 of the electronic pen 1B, the cap body 3B removed from the main body housing 21 is set so that the clip main body 341 of the clip 34 is orthogonal to the axial direction of the core 4. The distal end portion 4 a of the core body 4 is press-fitted into the through hole of the core-extracting portion 35 of the portion 341. Then, the front end 4a of the core 4 engages with the through hole 35a of the centering portion 35 and is held by the centering portion 35, so that the cap portion 3B is moved away from the main portion housing 21. By doing this, the core body 4 can be pulled out of the main body portion case 21.

  The shape of the through hole 35a of the centering portion 35 of the clip main portion 341 is not limited to a triangle, but the main point is to engage the core 4 with the tip 4a of the core 4 Any shape may be used as long as it can be pulled out, for example, a rhombus or other polygons.

  In the above-described embodiment, the main body 2 and the cap 3 are coupled by fitting the cap 3 to the cap fitting portion 211 of the main body casing 21, but the main body 2 and the cap 3 are , And may be screwed together. FIG. 10 is a view showing the electronic pen 1C configured to screw together the main body 2 and the cap 3.

  That is, as shown in FIG. 10, in the electronic pen 1 </ b> C of this example, a screw portion 214 is provided in the cap fitting portion 211 </ b> C instead of the ring-shaped protrusion 212. On the other hand, in the concave portion 31 of the cap portion 3, a screw portion 36 is formed instead of the ring-shaped concave groove 32.

  In the case of this example, the cap portion 3 is configured such that the cap fitting portion 211 of the main body portion housing 21 covers the core body holding portion 213 of the cap fitting portion 211 of the main body portion housing 21 with the concave portion 31. The screw portion 36 of the cap portion 3 is screwed into the screw portion 214 of the cap fitting portion 211 and is coupled to the main body housing 21 by being covered with and rotated.

[Other modifications]
In addition, although the electronic pen of the above-mentioned embodiment was a case of the electromagnetic induction method, the present invention can be applied to an electronic pen of an electrostatic coupling method (including an active electrostatic coupling method) Needless to say. In the case of an electrostatic coupling type electronic pen, the core is made of metal or conductive resin. In the case of an active electrostatic coupling type electronic pen, a signal from a signal generation circuit provided on a printed circuit board is sent from a conductive core and interacts with the tablet by electrostatic coupling.

  The core is not limited to being directly fitted to the writing pressure detection unit, but may be fitted to a pressure transmission unit fitted to the writing pressure detection unit.

DESCRIPTION OF SYMBOLS 1,1B, 1C ... Electronic pen, 2 ... Main body part, 3,3B ... Cap part, 4 ... Core body, 4E ... Replacement core, 10 ... Tablet, 21 ... Main body part housing | casing, 31 ... Recessed part, 33,33A ... Core removal part, 34 ... clip, 35 ... core removal part, 211 ... cap fitting part

Claims (14)

An electronic pen in which the tip of the core body protrudes from the opening in the axial direction of the main body housing, and the core body is detachably attached to the main body housing,
And a cap unit detachably coupled to the main unit casing in the axial direction,
The main body housing includes a core body holding portion capable of holding one or a plurality of core bodies on a side opposite to the opening side in the axial direction.
The cap portion includes a centering portion that is used to pull out the core body from the main body housing and remove it.
When using the centering part to pull out and release the core from which the tip projects from the opening in the axial direction of the main body housing, the one or more members are held by the core holding part An electronic pen characterized in that a core of a book is exposed. The cored portion engages with a tip end portion of the core body protruding from the opening and can maintain the engaged state so that the core body can be pulled out from the main body housing. The electronic pen according to claim 1, having a configuration. The electronic pen according to claim 1, wherein the centering portion is provided in a state that is visible from the outside in the cap that is coupled to the main body housing. The electronic pen according to claim 2, wherein the centering portion includes a recessed hole into which the tip end portion of the core body is inserted and engaged. The centering portion is formed on a surface of the cap portion on a side opposite to a side where the cap portion is coupled to the main body housing, in a direction intersecting with the axial direction. Description electronic pen. The electronic pen according to claim 2, wherein the centering portion is formed on a surface of the cap portion in a direction along the axial direction. The electronic pen according to claim 2, wherein the cap portion includes a clip portion, and the centering portion is provided in the clip portion. The cap portion is coupled to the main body housing in the axial direction on the opposite side of the main body housing from the one opening side from which the tip of the core body projects. The electronic pen according to claim 1. The electronic pen according to claim 1, wherein the cap portion is screwed to the main body housing. 2. The electronic pen according to claim 1, wherein the core body holding portion is formed of a sponge into which the core body can be inserted. The electronic pen according to claim 1, wherein the cap portion is coupled to the main body housing in a state of covering the core body holding portion. The electronic pen according to claim 1, wherein the electronic pen is used together with a tablet including an electronic pen placement unit. The electronic pen according to claim 12, wherein the core body is made of resin and interacts with the tablet by an electromagnetic induction method. The electronic pen according to claim 12, wherein the core is made of a conductor and interacts with the tablet by an electrostatic coupling method.

Images