JPWO2016185915A1 - Electronic pen - Google Patents

Abstract

Provided is an electronic pen having a structure in which even a thin core is hard to break. An electronic device having a cylindrical housing having an opening on one side, a core body that is housed in the housing and has a tip protruding from the opening, and a writing pressure detection unit that detects writing pressure applied to the core body It is a pen. The core body includes a middle core portion and a pipe portion made of a member having rigidity higher than that of the middle core portion. The middle core portion is inserted into the hollow portion of the pipe portion, and is locked to the pipe portion with at least a tip portion protruding from one end portion in the axial direction of the pipe portion. The front end portion of the center core portion is used as the front end of the core body, and when the front end portion of the center core portion protrudes from the opening portion of the housing, a part of the pipe portion also protrudes from the opening portion. The pen pressure applied to the tip of the middle core is transmitted to the pen pressure detector via the pipe.

Description

  The present invention relates to an electronic pen that is used together with a position detection device and has a writing pressure detection function.

  In recent years, a coordinate input device has been used as an input device for various electronic devices, and an electronic pen as an input tool of the coordinate input device has been increasingly used. As a coordinate input device, an electromagnetic induction method is mainly used. As one of the electromagnetic induction methods, there is a method in which a magnetic field from a sensor is received by a resonance circuit provided in an electronic pen and fed back to the sensor.

  This electromagnetic induction type coordinate input device is an example of a position detection device including a sensor in which a large number of loop coils are arranged in the X-axis direction and the Y-axis direction of the coordinate axis, and an inductance element wound around a magnetic core. And an electronic pen as a pen-shaped position indicator having a resonance circuit composed of a coil and a capacitor.

  The position detection device supplies a transmission signal having a predetermined frequency to the loop coil of the sensor and transmits it to the electronic pen as electromagnetic energy. The resonance circuit of the electronic pen is configured to have a resonance frequency corresponding to the frequency of the transmission signal, and stores electromagnetic energy based on an electromagnetic induction action with the loop coil of the sensor. Then, the electronic pen returns the electromagnetic energy stored in the resonance circuit to the loop coil of the sensor of the position detection device.

  The sensor loop coil detects the electromagnetic energy from the electronic pen. The position detection device detects the position on the sensor indicated by the electronic pen in the X-axis direction and Y based on the position of the loop coil that supplied the transmission signal and the position of the loop coil that detected the electromagnetic energy from the resonance circuit of the electronic pen. Detect the coordinate value in the axial direction.

  FIG. 12A shows an example of a schematic configuration of a conventional electronic pen 100. The electronic pen 100 in the example of FIG. 12A is described in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2009-86925).

  A case (housing) 101 of the electronic pen 100 described in Patent Document 1 has a bottomed cylindrical shape including a first case 102 and a second case 103 assembled and coupled in the axial direction. Prepare. An opening 102a for projecting the one end 109a side of the rod-shaped core body 109 whose one end 109a side is a pen tip is formed on one end side in the axial direction of the first case. In the hollow portion of the case 101, a coil 104, a writing pressure detection unit 105, and a printed circuit board 107 on which electronic components such as a capacitor 106 that forms a resonance circuit together with the coil 104 are sequentially arranged in the axial direction. Is stored.

  The coil 104 is wound around a ferrite core 108 as an example of a cylindrical magnetic core having a through hole 108a in the axial direction. The core body 109 is configured so as not to be mechanically coupled to the ferrite core 108, and is provided so as to penetrate the through hole 108 a of the ferrite core 108. A writing pressure detection unit 105 is housed on the opposite side of the ferrite core 108 from the opening 102 a of the first case 102, and the other end 109 b of the core body 109 is fitted into the writing pressure detection unit 105. Combined. The core body 109 is moved and displaced in the axial direction in accordance with the applied writing pressure. The writing pressure detection unit 105 in this example has a capacitor configuration in which the displacement generated in the core body 109 is a change in capacitance, and detects the writing pressure as a change in capacitance of the capacitor. It is configured.

  The writing pressure detection unit 105 is electrically connected to electronic components such as a capacitor of the printed circuit board 107 through terminals 105a and 105b, and is also electrically connected to one end and the other end of the coil 104. The capacitor constituting the writing pressure detection unit 105 constitutes a resonance circuit together with a coil and a predetermined capacitor. When pressure (writing pressure) is applied to the core 109, the capacitance of the capacitor constituting the writing pressure detection unit 105 changes, and the resonance frequency of the resonance circuit changes. The electronic pen 100 transmits and receives electromagnetic waves to and from the sensor of the position detection device using this resonance circuit. The position detection device detects the indicated position of the core 109 of the electronic pen 100 as the coordinate position where electromagnetic waves are transmitted to and received from the electronic pen 100, and the frequency (resonance frequency) of the signal fed back from the electronic pen 100 is detected. The writing pressure applied to the electronic pen is detected.

  As described above, in the conventional electromagnetic induction type electronic pen, the pressure applied to the core 109 is detected by writing the core 109 through the through hole 108a in the axial direction of the ferrite core 108. It is configured to be able to detect the contact of the electronic pen 100 with the input surface of the sensor of the position detection device.

  By the way, due to the recent preference for downsizing, portable electronic devices are increasingly required to be downsized. The electronic pen is used together with a position detecting device for this kind of small electronic device, and a thinner one is required.

  However, when the electronic pen is thin, the ferrite core as an example of the magnetic core around which the coil 104 is wound needs to be thin, but the ferrite core is hard, and such a thin ferrite core has a thin core. Conventionally, it has been difficult to form a through hole having an accurate dimensional accuracy through which a body is inserted.

  Therefore, as shown in FIG. 12B, the thin ferrite core 108A housed in the thin housing 102A of the thin electronic pen 100A is not provided with a through-hole for penetrating the core body. An electronic pen has been proposed in which a concave portion 1081 is formed at the end of the ferrite core 108A on the pen tip side, and the core body 109A is fitted in the concave portion 1081 (Patent Document 2 (Japanese Patent Laid-Open No. 2014-216774). No.)).

  In the case of this electronic pen 100A, the core body 109A has a shape corresponding to the pen tip side 109a of the core body 109 in the case of the electronic pen 100 in FIG. 12A, and the pen tip side of the ferrite core 108A. A projection 1091 that fits into the recess 1081 at the end of the projection. Then, the protrusion 1091 of the core body 109A is fitted into the recess 1081 of the ferrite core 108A, whereby both are integrally coupled. For this reason, in the electronic pen 100A shown in FIG. 12B, the ferrite core 108A integrally coupled to the core body 109A is arranged in the axial direction in accordance with the writing pressure applied to the core body 109A. It moves and the pen pressure is transmitted to the pen pressure detector (not shown in FIG. 12B).

JP 2009-86925 A Japanese Patent Application Laid-Open No. 2014-21674

  As described above, in the case of the electronic pen 100A of Patent Document 2, since the ferrite core 108A moves in the axial direction according to the writing pressure, the coil 104A wound around the ferrite core 108A There has been a problem that the strength of electromagnetic coupling changes depending on the writing pressure.

  By the way, recently, it has become possible to form a through hole with an accurate dimensional accuracy for inserting a thin core into a thin ferrite core, so that the above-described problem of the electronic pen 100A of Patent Document 2 is solved. became.

  That is, as shown in FIG. 12C, a thin through hole 108Ba can be formed in a thin ferrite core 108B around which the coil 104B is wound, and a thin core made of, for example, resin is formed in the through hole 108Ba. The body 109B can be inserted. Then, the side opposite to the tip 109Ba of the core body 109B is inserted and protruded through the ferrite core 108B in the same manner as in FIG. 12A, and the protruding end portion 109Bb is set as a writing pressure detecting portion (FIG. The problem of the electronic pen 100A shown in FIG. 12B can be solved by fitting to (B) (not shown).

  However, when the through hole 108Ba is formed in the thin ferrite core 108B as shown in FIG. 12C and the core body 109B is inserted through the through hole 108Ba, the core body 109B made of resin, for example, is too thin. For this reason, there arises a problem that the core body 109B is easily broken. There is also a problem that the core body 109B bends in the through hole 108Ba of the ferrite core 108B.

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

In order to solve the above problems, the present invention provides:
A cylindrical housing having an opening on one side;
A core body housed in the housing and having a tip protruding from the opening;
A pen pressure detection unit for detecting a pen pressure applied to the core;
Have
The core is
It has a core part and a pipe part,
The middle core portion is inserted into the hollow portion of the pipe portion, and at least a tip portion is locked to the pipe portion in a state of protruding from one end portion in the axial direction of the pipe portion,
When the tip of the core is the tip of the core, and when the tip of the core protrudes from the opening of the housing, a part of the pipe also protrudes from the opening. ,
A writing pressure applied to the tip of the central core portion is determined according to the applied writing pressure, and the core body has an axial core of the cylindrical casing with the side surface of the pipe portion facing the opening. Provided is an electronic pen that is slidable in a direction so as to be transmitted to the writing pressure detection unit through the pipe unit.

  According to the electronic pen of the invention of claim 1 having the above-described configuration, the core body includes the center core portion and a pipe portion made of a member having rigidity higher than the center core portion, and the center core portion is the pipe portion. Is inserted into the hollow portion, and at least the tip portion is configured to be locked to the pipe portion in a state of protruding from one end portion in the axial direction of the pipe portion.

  And when the front-end | tip part of a center part protrudes from the said opening part of a housing | casing, a part of pipe part will also be in the state which protrudes from an opening part, and the front-end | tip part of the center part which protrudes from an opening part is a pipe part. It will be in the state protected by a part of. In addition, since the pipe part comes to face the wall part of the opening part of the housing, the core body should be configured not to be broken even when the core body collides with the wall part of the opening part. Can do.

  It is generally known that a pipe structure has a greater resistance to bending stress than a solid rod having the same thickness. The core body of the electronic pen according to the present invention is configured by inserting the center core portion into the pipe portion having a large resistance to bending stress. And in this invention, the pipe part is comprised by the member whose rigidity is larger than a center core part.

  Therefore, according to the present invention, there is provided an electronic pen having a structure in which, even if a thin core body is inserted through a thin through hole of a thin magnetic core, the core body is not easily broken by the pipe portion. Can do.

  According to this invention, even if it is a thin core, an electronic pen having a structure in which the core is hard to break can be provided.

It is a figure for demonstrating the structural example of 1st Embodiment of the electronic pen by this invention. It is a figure for demonstrating the structural example of the electronic pen main-body part of the electronic pen of 1st Embodiment. It is a figure for demonstrating the structural example of the electronic pen main-body part of the electronic pen of 1st Embodiment. It is a figure for demonstrating the structural example of the core of the electronic pen of 1st Embodiment. It is a figure which shows the circuit structure of 1st Embodiment of the electronic pen by this invention with the circuit structure of the position detection apparatus used with the said electronic pen. It is a figure for demonstrating the other structural example of the core in embodiment of the electronic pen by this invention. It is a figure for demonstrating the other structural example of the core in embodiment of the electronic pen by this invention. It is a figure for demonstrating the other structural example of the core in embodiment of the electronic pen by this invention. It is a figure for demonstrating the structural example of 2nd Embodiment of the electronic pen by this invention. It is a figure for demonstrating the circuit structure of 2nd Embodiment of the electronic pen by this invention. It is a figure shown with the circuit structure of the position detection apparatus used with 2nd Embodiment of the electronic pen by this invention. It is a figure for demonstrating an example of the conventional electronic pen.

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

[First Embodiment]
FIG. 1 is a diagram showing a configuration example of a first embodiment of an electronic pen according to the present invention. In the electronic pen 1 according to the first embodiment, the electronic pen main body 3 is housed in the hollow portion 2a of the cylindrical housing 2, and the pen tip side of the electronic pen main body 3 is moved by the knock cam mechanism 4. A knock-type configuration is provided that is inserted and removed from the opening 2b side at one end of the casing 2 in the longitudinal direction. In this embodiment, the electronic pen main body 3 has a cartridge type configuration and is detachable from the housing 2.

  FIG. 1A shows a state in which the entire electronic pen main body is housed in the hollow portion 2 a of the housing 2, and FIG. 1B shows the pen tip of the electronic pen main body by the knock cam mechanism 4. The side has shown the state protruded from the opening part 2b of the housing | casing 2. FIG. In the example of FIG. 1, the housing 2 of the electronic pen 1 is made of a transparent synthetic resin, and the inside thereof is shown through.

  The electronic pen 1 of this embodiment is configured to be compatible with a commercially available knock-type ballpoint pen.

  The casing 2 and the knock cam mechanism portion 4 provided in the casing 2 have the same configuration as a well-known commercially available knock-type ballpoint pen, and have the same dimensional relationship. In other words, the housing 2 and the knock cam mechanism portion 4 may be a commercially available knock-type ballpoint pen housing and knock cam mechanism portion as they are.

  As shown in FIG. 1, the knock cam mechanism unit 4 has a known configuration in which a cam main body 41, a knock bar 42, and a rotor 43 are combined. The cam body 41 is formed on the inner wall surface of the cylindrical housing 2. The knock bar 42 is configured such that an end 42a protrudes from the opening 2c on the opposite side of the pen tip side of the housing 2 so that the knock operation of the user can be received. The rotor 43 includes a fitting portion 43a into which an end portion of the electronic pen body portion 3 opposite to the pen tip side is fitted.

  In the state of FIG. 1A, when the end portion 42a of the knock bar 42 is pressed, the electronic pen main body 3 is locked in the state of FIG. The pen tip side of the electronic pen body 3 is projected from the opening 2b of the housing 2. When the end 42a of the knock bar 42 is pressed again from the state shown in FIG. 1B, the locked state is released by the knock cam mechanism 4, and the housing of the electronic pen main body 3 is released by the return spring 5. The position in the body 2 returns to the state of FIG. Since the detailed configuration and operation of knock cam mechanism 4 are well known, the description thereof is omitted here.

  FIG. 2 is a diagram showing a configuration example of the electronic pen main body 3 in comparison with a replacement core of a commercially available knock-type ballpoint pen. That is, FIG. 2 (A) shows a replacement core 6 of a commercially available knock-type ballpoint pen, and FIG. 2 (B) shows a configuration example of the electronic pen main body 3 of this embodiment. FIG. 3 is a partial enlarged view for explaining the configuration of the pen tip side of the electronic pen main body 3. Further, FIG. 4 is a diagram for explaining the configuration of the core body mounted on the electronic pen main body 3.

  As shown in FIG. 2 (A), a commercially available knock-type ballpoint pen replacement core 6 has a pen point portion 61 having a ball disposed at the tip thereof and an ink storage portion 62 coupled by a coupling portion 63. It has a well-known integrated structure. The coupling part 63 has the same diameter as the ink storage part 62.

  On the other hand, in the electronic pen main body portion 3 of this embodiment, as shown in FIG. 2B, a magnetic core around which a coil 31 is wound, in this example, a ferrite core 32 is coupled to a cylindrical body portion 33. ing. Then, the core body 34 is inserted through a through hole (not shown in FIG. 2) of the ferrite core 32 and, as will be described later, a writing pressure detection unit (in FIG. 2) provided in the cylindrical body portion 33. And is provided as a part of the electronic pen main body 3. As shown in FIG. 2, the core body 34 has one end portion 34a (hereinafter referred to as a tip portion 34a) protruding from the ferrite core 32 as a nib.

  3A is an exploded enlarged view of the ferrite core 32 around which the coil 31 is wound, a part of the cylindrical body portion 33, and a portion of the core body 34. FIG. In this example, the ferrite core 32 has a through-hole 32d in the axial direction with a predetermined diameter r1 (for example, r1 = 1 mm) through which the core body 34 is inserted, for example, in a cylindrical ferrite material. ing. A taper portion 32e that is gradually tapered is formed on the pen tip side of the ferrite core 32. Due to the taper portion 32e, the magnetic flux passing through the ferrite core 32 becomes high density at the taper portion 32e, and the magnetic coupling with the sensor of the position detection device is more effective than when the taper portion 32e is not provided. Can be strong.

  And in this embodiment, as shown to FIG. 3 (A), the coil 31 is not wound over the full length of the axial direction of the ferrite core 32, but is wound partially. In other words, in this example, the coil 31 has a winding length that is approximately ½ of the entire length of the ferrite core 32, and as shown in FIG. The turning portion 32a is a position biased toward the coupling portion side of the ferrite core 32 with the cylindrical body portion 33.

  When the ferrite core 32 is viewed in the axial direction, the portion from the end on the pen tip side to one end of the coil winding portion 32a is the first coil non-winding portion where the coil is not wound. The second coil non-winding in which the coil 31 is not wound from the other end of the coil winding portion 32a on the side of the coupling portion with the cylindrical body portion 33 of the ferrite core 32 is also formed. Part 32c. The length of the second coil non-winding portion 32 c in the axial direction is a short length for coupling with the cylindrical body portion 33. On the other hand, the length in the axial direction of the first coil non-winding portion 32b is about the length of the second coil non-winding portion 32c from about ½ of the total length of the ferrite core 32 in this example. It is said that it is relatively long minus

  In this embodiment, a writing pressure detection unit 35 is provided in the vicinity of the coupling portion between the cylindrical body portion 33 and the ferrite core 32. In this example, the writing pressure detection unit 35 has a configuration using a semiconductor element whose capacitance is variable according to the writing pressure as disclosed in, for example, Japanese Patent Application Laid-Open No. 2013-161307. The writing pressure detection unit 35 uses, for example, writing pressure detection means having a well-known mechanical structure described in Japanese Patent Application Laid-Open No. 2011-186803, and the capacitance changes according to the writing pressure. It can also be set as the structure of the variable capacitor which carries out.

  A printed circuit board 36 is further accommodated in the cylindrical body portion 33. The printed circuit board 36 is provided with a capacitor 37 that is connected in parallel to the coil 31 to form a resonance circuit. And the variable capacitor 35C comprised by the writing pressure detection part 35 is connected in parallel with the capacitor 37 currently formed in this printed circuit board 36, and comprises a part of said resonance circuit. (See FIG. 6 below).

  Then, as shown in FIG. 3B, all or part of the second coil non-winding portion 32 c of the ferrite core 32 is fitted into the recess 33 a provided in the cylindrical body portion 33. Thus, the ferrite core 32 is coupled to the cylindrical body portion 33. Although not shown, when the ferrite core 32 is coupled to the cylindrical body portion 33, the ends 31 a and 31 b of the coil 31 are parallel to the capacitor 37 provided on the printed circuit board 36 of the cylindrical body portion 33. It is electrically connected so that it may be connected to.

  As shown in FIG. 3A, the core body 34 has a rod-like configuration in which the maximum diameter is smaller than the diameter r <b> 1 of the through hole of the ferrite core 32. In this example, as shown in FIG. 4A, the core body 34 includes a pipe portion 341 and a middle core portion 342 that is inserted through the hollow portion of the pipe portion 341.

  In this example, the middle core part 342 is made of a relatively hard and elastic resin material, for example, POM (Polyoxymethylene), and at least a tip part 342a on one end side of the middle core part 342 is a pipe part 341. A pen tip is formed by projecting from one end side in the axial direction. Further, the other end 342 b side of the center core part 342 protrudes from the other end side in the axial direction of the pipe part 341, and constitutes a writing pressure transmission unit for transmitting the writing pressure to the writing pressure detection unit 35. . In particular, in this example, the other end portion 342b side of the core portion 342 constitutes a fitting portion that fits the writing pressure detecting portion 35 in order to transmit the writing pressure, as shown in FIG. .

  In this example, the other end portion 342b side of the core portion 342 constitutes a fitting portion that fits the writing pressure detection portion 35, but another member that fits the writing pressure detection portion 35. The other end portion 342b side of the core portion 342 is fitted to the pressing member, and the writing pressure applied to the tip of the core body 34 is applied to the writing pressure detection portion 35. You may comprise so that it may transmit via a press member.

  In addition, the material of the center core part 342 is not limited to POM, and a resin material and other materials that take into account writing as a pen tip can also be used.

  The pipe part 341 is made of a material having rigidity higher than that of the core part 342, in this example, a metal, for example, SUS. The pipe portion 341 has an outer diameter r2 that is smaller than the diameter r1 of the through hole 32d of the ferrite core 32. And the inner diameter (diameter of the hollow part 341a) r3 of the pipe part 341 is selected to a value that allows the core part 342 to pass through the hollow part 341a.

  In this example, the diameter of the other end 342b of the middle core part 342 is selected to be equal to the outer diameter r2 of the pipe part 341, as shown in FIG. And the diameter of the part except the other edge part 342b of the center part 342 is made into the fixed diameter r3 'slightly smaller than the internal diameter r3 of the pipe part 341. As shown in FIG. And the length of the said diameter r3 'part of the center part 342 is selected longer than the length of the pipe part 341. FIG.

  Therefore, when the entire portion of the core portion 342 having the diameter r3 ′ excluding the other end portion 342b is inserted into the hollow portion 341a of the pipe portion 341, as shown in FIG. The other end portion 342b of the pipe portion 342 protrudes from the other end portion of the pipe portion 341, and at least the front end portion 342a on the one end side of the center core portion 342 serves as a pen tip and one end of the pipe portion 341. It will be in the state which protrudes from a part.

  In this example, a diameter slightly larger than the diameter r3 ′ and the diameter r3 is provided in the vicinity of the other end 342b of the diameter r3 ′ portion of the center core portion 342, as shown in FIG. 4C. A bulging portion 342c that bulges is formed. The central core portion 342 is attached to the pipe portion 341 such that the bulging portion 342c is pushed into the hollow portion 341a of the pipe portion 341. Accordingly, when the entire core portion 342 having the diameter r3 ′ excluding the other end portion 342b is inserted into the hollow portion 341a of the pipe portion 341, the middle core portion 342 becomes the bulged portion 342c. Thus, the pipe portion 341 is locked.

  As described above, the core body 34 is configured integrally with the pipe portion 341 by inserting and fitting the middle core portion 342 into the pipe portion 341 as shown in FIG. The core body 34 can be pulled out from the pipe portion 341 to the other end portion 342b side after the core body 34 is integrally formed. That is, the core part 342 is configured to be replaceable with respect to the pipe part 341.

  As shown in FIG. 3B, the core 34 has a through-hole formed in the ferrite core 32 from the side where the tapered portion 32e is formed, in a state where the ferrite core 32 and the cylindrical body portion 33 are coupled. 32d is inserted. The core body 34 is configured such that the other end 342b of the center core part 342 on the side opposite to the tip end part 342a on the one end side of the center core part 342 constituting the nib is in the cylindrical body part 33. The fitting portion 35a of the writing pressure detection portion 35 is fitted. In this case, although detailed illustration is omitted, an elastic material such as elastic rubber is disposed in the fitting portion 35a of the writing pressure detecting portion 35, and the other end of the core portion 342 of the core body 34 is disposed. By holding the portion 342b with the elastic material, the core body 34 is prevented from easily falling off. However, if the user applies a force so as to pull out the core body 34, the fitting between the core body 34 and the fitting portion 35 a of the writing pressure detection unit 35 is easily released, and the core body 34 is pulled out. Can do. That is, the core body 34 can be replaced.

  Thus, in the state where the other end portion 342b of the core portion 342 of the core body 34 is fitted to the fitting portion 35a of the writing pressure detection unit 35, as shown in FIG. The tip end portion 342a on one end side of the center core portion 342 is in a state of protruding from the ferrite core 32 as a pen tip. Furthermore, in this example, one end portion side of the pipe portion 341 of the core body 34 also protrudes from the ferrite core 32 together with the tip portion 342a on the one end portion side of the middle core portion 342. As a result, the end portion 342a on one end side of the core portion 342 protruding from the ferrite core 32 is protected (reinforced) by a portion protruding from the ferrite core 32 of the pipe portion 341.

  In the case of this example, as shown in FIGS. 2A and 2B, the size of the pen tip side of the electronic pen main body 3 is substantially equal to the size of the pen tip side of the replacement core 6 of the ballpoint pen. It is comprised so that it may become. That is, the diameter of the ferrite core 32 provided on the pen tip side of the electronic pen main body 3 is configured to be substantially equal to the diameter R1 of the pen tip 61 of the replacement core 6 of the ballpoint pen. Further, the total length of the length of the portion protruding from the ferrite core 32 of the distal end portion 34a of the core body 34 and the length of the first coil non-winding portion 32b of the ferrite core 32 is shown in FIGS. ), The length L1 of the pen point portion 61 of the ballpoint pen replacement core 6 is configured to be substantially equal to the length L1.

  Further, the diameter of the coil winding portion 32a around which the coil 31 of the ferrite core 32 of the electronic pen main body portion 3 is wound and the diameter of the cylindrical body portion 33 are set to the diameter R2 of the ink storage portion 62 of the replacement core 6 of the ballpoint pen. It is substantially equal and larger than the diameter R1 of the pen tip 61 (R2> R1). Note that the diameter of the opening 2b of the housing 2 is smaller than the diameter R2. Therefore, the coil winding part 32a cannot protrude outside from the opening 2b.

  2A and 2B, the ferrite core 32 and the cylindrical body portion 33 are coupled, and the core body 34 is detected through the through hole of the ferrite core 32 to detect the writing pressure of the cylindrical body portion 33. The length (full length) of the electronic pen main body portion fitted to the portion 35 is selected to be equal to the full length L2 of the ballpoint pen replacement core 6.

  The electronic pen main body 3 configured as described above can be accommodated in the housing 2 by fitting the cylindrical body portion 33 to the fitting portion 43 a of the rotor 43 of the knock cam mechanism portion 4. . In the electronic pen 1 according to this embodiment, the user presses the end 42a of the knock bar 42 when using the position detection device. Then, in the electronic pen 1, as shown in FIGS. 1B and 3B, a part of the tip end portion 34a of the core body 34 and the first coil non-winding portion 32b of the ferrite core 32 is enclosed. It will be in the state which protrudes from the opening part 2b of the body 2. FIG. In this state, the user of the electronic pen 1 performs an input operation of the indicated position on the sensor of the position detection device.

  When the use of the electronic pen 1 is completed, the end portion 42a of the knock bar 42 is pressed again, so that the entire electronic pen main body 3 is placed in the hollow portion 2a of the housing 2 as shown in FIG. It can be made into the state to accommodate. At this time, the entire electronic pen main body 3 is accommodated in the hollow portion 2 a of the housing 2, and the tip 34 a of the core 34 of the electronic pen main body 3 is protected by the housing 2.

[Effect of the first embodiment]
In the electronic pen 1 of this embodiment, when using the electronic pen 1 in which the tip 34a of the core 34 protrudes to the outside, not only the core 34 but also the first coil non-winding portion 32b of the ferrite core 32 is used. Also protrudes from the opening 2b of the housing 2, and the distance from the tip of the tapered portion 32e of the ferrite core 32 to the input surface of the sensor is shortened. Therefore, according to the electronic pen 1 of this embodiment, the electromagnetic coupling with the sensor is stronger than the conventional electronic pen in which the ferrite core 32 remains in the hollow portion 2a of the housing 2. Furthermore, in this embodiment, since the tip end 34a side of the core body 34 of the ferrite core 32 is a tapered portion 32e, the sectional area of the tip of the ferrite core 32 is reduced, and the magnetic flux density is further increased. It becomes strongly electromagnetically coupled with the sensor.

  Therefore, the electronic pen 1 of this embodiment can be strongly electromagnetically coupled to the sensor even when the electronic pen 1 is thinned, and the position detection device can detect the detection of the indicated position with the electronic pen with high sensitivity. Will be able to.

  As the electronic pen 1 is made thinner, the core body 34 becomes very thin and the strength becomes a problem. According to the above-described embodiment, the core body 34 includes the pipe portion 341 and the middle core portion 342. Combined with the fact that the pipe part 341 has a higher resistance to bending stress than a solid rod-like body, and that the pipe part 341 is made of a material having rigidity higher than that of the core part 342, The strength of the core body 34 can be increased.

  Further, the core body 34 protruding from the end portion of the through hole 32d of the ferrite core 32 as the pen tip side is not only the tip portion 342a on one end side of the center core portion 342 but also one end portion of the pipe portion 341. Is also included. Therefore, one end portion 342a of the core portion 342 of the core body 34 protruding from the end portion of the through hole 32d of the ferrite core 32 is protected by the pipe portion 341. Even if the end portion 342a is very thin, the damage can be prevented more effectively.

  That is, when the tip end portion 342a protruding from the pipe portion 341 of the core portion 342 of the core body 34 is configured to face the wall portion of the opening 2b of the housing 2, the core portion 342 is Since it is a resin and has low rigidity, when the front end portion 342a of the center core portion 342 and the wall portion of the opening 2b abut each other, the front end portion 342a of the center core portion 342 may be broken.

  On the other hand, in the electronic pen 1 of this embodiment, the pipe portion 341 of the core body 34 is opposed to the wall portion of the opening portion 2b of the housing 2, and therefore the wall of the opening portion 2b. When the core body 34 abuts the portion, the abutting portion of the core body 34 with the wall portion becomes a metal pipe portion 341.

  As described above, the pipe-shaped member has higher rigidity than the solid rod-shaped body even if the same material is used. Moreover, in this embodiment, the pipe portion 341 uses a metal having a higher rigidity than the center core portion 342 made of resin. Therefore, in the electronic pen 1 of this embodiment, even if the core body 34 abuts against the wall portion of the opening 2b of the housing 2, the abutting portion of the core body 34 is more rigid than the middle core portion 342. A large metal pipe portion 341 is formed, and the tip end portion 342a of the core portion 342 of the core body 34 can be configured to be difficult to break. With this configuration, according to the electronic pen 1 of this embodiment, even if the tip portion 342a of the center core portion 342 is the same metal as the pipe portion 341, the structure is less likely to break than the core of the metal rod.

  Further, since the outer peripheral surface of the metal pipe portion 341 has a smaller friction coefficient than that of the resin, even if the wall portion of the opening 2b and the pipe portion 341 of the core body 34 abut against each other, the metal pipe portion 341 slips compared to the resin. In this respect, the tip end portion 342a of the core body 34 can be made difficult to break.

  Furthermore, in this embodiment, when the tip end 34 a of the core body 34 protrudes from the opening 2 b of the housing 2, a part of the coil non-winding portion 32 b of the ferrite core 32 is also the opening 2 b of the housing 2. The length of the tip 34a side of the core 34 protruding from the end of the through hole 32d of the ferrite core 32 may be the minimum length as a pen tip. In other words, in the electronic pen main body portion 3 of this embodiment, the core body 34 is inserted into the through hole 32d of the ferrite core 32 except for the necessary minimum tip portion 34a protruding outside, and is protected. ing. Therefore, according to the electronic pen 1 and the electronic pen main body 3 of this embodiment, even if the core 34 is thinned, the tip of the core 34 is protected by the ferrite core 32 in addition to the pipe 341. Therefore, the effect that the damage can be prevented more is produced.

  And according to the above-mentioned embodiment, since electronic pen main-body part 3 can be reduced in size, electronic pen main-body part 3 can be set as the structure which can take compatibility with the replacement core of a commercially available ball-point pen. .

  When the electronic pen main body 3 is configured to be compatible with a replacement core of a commercially available ballpoint pen, there is an advantage that the casing 2 of the electronic pen 1 can be diverted to the casing of a commercially available ballpoint pen. . That is, the electronic pen 1 can be configured by housing the electronic pen main body 3 of this embodiment in the ballpoint pen housing instead of the ballpoint pen replacement core.

  In the example of FIG. 2, the coil 31 is wound around a substantially ½ length portion of the ferrite core 32, but the length of the portion of the ferrite core 32 around which the coil 31 is wound is limited to this. It is not a matter of choice. And the total length of the length of the front-end | tip part 34a of the core 34 and the length of the coil unwinding part 32b of the ferrite core 32 is the above-mentioned in ensuring compatibility with the replacement core of a commercially available ball-point pen. It is not necessarily limited to the length L1, but it may be longer than the length L1.

[Circuit Configuration for Position Detection and Pen Pressure Detection in a Position Detection Device Used with Electronic Pen 1]
Next, a circuit configuration example and operation of the position detection device 400 that detects the indicated position by the electronic pen 1 and the writing pressure applied to the electronic pen 1 according to the above-described embodiment will be described with reference to FIG. To do.

  As shown in FIG. 5, the electronic pen 1 includes a coil 31 as an inductance element, a variable capacitor 35 </ b> C configured by a writing pressure detection unit 35, and a resonance capacitor 37 housed in a cylindrical body unit 33. Are provided with a resonant circuit connected in parallel.

  On the other hand, in the position detection device 400, an X-axis direction loop coil group 411 and a Y-axis direction loop coil group 412 are laminated to form a position detection coil 410. Each of the loop coil groups 411 and 412 includes, for example, n and m rectangular loop coils. Each loop coil which comprises each loop coil group 411,412 is arrange | positioned so that it may overlap in order along with equal intervals.

  Further, the position detection device 400 is provided with a selection circuit 413 to which the X-axis direction loop coil group 411 and the Y-axis direction loop coil group 412 are connected. The selection circuit 413 sequentially selects one of the two loop coil groups 411 and 412.

  Further, the position detection device 400 includes an oscillator 421, a current driver 422, a switching connection circuit 423, a reception amplifier 424, a detector 425, a low-pass filter 426, a sample hold circuit 427, and an A / D conversion. A circuit 428, a synchronous detector 429, a low-pass filter 430, a sample and hold circuit 431, an A / D conversion circuit 432, and a processing control unit 433 are provided. The processing control unit 433 is configured by a microprocessor.

  The oscillator 421 generates an AC signal having a frequency f0. Then, the oscillator 421 supplies the generated AC signal to the current driver 422 and the synchronous detector 429. The current driver 422 converts the AC signal supplied from the oscillator 421 into a current and sends it to the switching connection circuit 423. The switching connection circuit 423 switches the connection destination (transmission side terminal T, reception side terminal R) to which the loop coil selected by the selection circuit 413 is connected under the control of the processing control unit 433. Among the connection destinations, a current driver 422 is connected to the transmission side terminal T, and a reception amplifier 424 is connected to the reception side terminal R.

  The induced voltage generated in the loop coil selected by the selection circuit 413 is sent to the reception amplifier 424 via the selection circuit 413 and the switching connection circuit 423. The reception amplifier 424 amplifies the induced voltage supplied from the loop coil and sends it to the detector 425 and the synchronous detector 429.

  The detector 425 detects the induced voltage generated in the loop coil, that is, the received signal, and sends it to the low-pass filter 426. The low-pass filter 426 has a cutoff frequency sufficiently lower than the above-described frequency f0, converts the output signal of the detector 425 into a DC signal, and sends it to the sample hold circuit 427. The sample hold circuit 427 holds a voltage value at a predetermined timing of the output signal of the low-pass filter 426, specifically, a predetermined timing during the reception period, and sends it to an A / D (Analog to Digital) conversion circuit 428. . The A / D conversion circuit 428 converts the analog output of the sample hold circuit 427 into a digital signal and outputs it to the processing control unit 433.

  On the other hand, the synchronous detector 429 synchronously detects the output signal of the reception amplifier 424 with the AC signal from the oscillator 421, and sends a signal having a level corresponding to the phase difference therebetween to the low-pass filter 430. The low-pass filter 430 has a cutoff frequency sufficiently lower than the frequency f 0, converts the output signal of the synchronous detector 429 into a DC signal, and sends it to the sample hold circuit 431. The sample hold circuit 431 holds a voltage value at a predetermined timing of the output signal of the low-pass filter 430 and sends it to an A / D (Analog to Digital) conversion circuit 432. The A / D conversion circuit 432 converts the analog output of the sample hold circuit 431 into a digital signal and outputs the digital signal to the processing control unit 433.

  The process control unit 433 controls each unit of the position detection device 400. That is, the processing control unit 433 controls the selection of the loop coil in the selection circuit 413, the switching of the switching connection circuit 423, and the timing of the sample hold circuits 427 and 431. Based on the input signals from the A / D conversion circuits 428 and 432, the processing control unit 433 transmits radio waves from the X-axis direction loop coil group 411 and the Y-axis direction loop coil group 412 with a certain transmission duration (continuous transmission period). Send it.

  An induced voltage is generated in each loop coil of the X-axis direction loop coil group 411 and the Y-axis direction loop coil group 412 by radio waves transmitted (returned) from the electronic pen 1. The processing control unit 433 calculates the coordinate values of the indicated positions of the electronic pen 1 in the X-axis direction and the Y-axis direction based on the level of the voltage value of the induced voltage generated in each loop coil. Further, the processing control unit 433 detects the writing pressure based on the level of the signal corresponding to the phase difference between the transmitted radio wave and the received radio wave.

  In this manner, in the position detection device 400, the position of the approaching electronic pen 1 is detected by the processing control unit 433. And the information of the pen pressure value of the electronic pen 1 is obtained by detecting the phase of the received signal.

  Since the electronic pen body 3 can be made thinner, the electronic pen body 3 can be configured to be compatible with a commercially available ballpoint pen replacement core.

  When the electronic pen main body 3 is configured to be compatible with a replacement core of a commercially available ballpoint pen, there is an advantage that the casing 2 of the electronic pen 1 can be diverted to the casing of a commercially available ballpoint pen. . That is, the electronic pen 1 can be configured by housing the electronic pen main body 3 of this embodiment in the ballpoint pen housing instead of the ballpoint pen replacement core.

[Modification of First Embodiment]
In the example of the first embodiment described above, the core body 34 is inserted into the pipe portion 341 and the hollow portion 341a of the pipe portion 341, and the tip end portion 342a on one end side forms the pen tip. The other end portion 342b is composed of a central core portion 342 that constitutes a writing pressure transmission unit that transmits the writing pressure to the writing pressure detection unit 35. However, the configuration of the core is not limited to such a configuration.

<First other example of core>
FIG. 6 is a diagram for explaining a configuration example of a core body 34A of a first other example that can be used in the electronic pen 1 of the first embodiment.

  In the core body 34A of this example, as shown in FIG. 6A, the pipe portion 341A having the same configuration as the pipe portion 341 of the example of the first embodiment described above is used. The configuration of the part is different from the example of the first embodiment described above. That is, in the core body 34A of this example, as shown in FIG. 6A, the center core portion 342A includes a pen tip side portion 3421 that constitutes a tip portion on one end side of the center core portion 342A, It is separated into a writing pressure transmission unit 3422 that transmits the writing pressure to the writing pressure detection unit 35. In this example, the pen tip side portion 3421 and the writing pressure transmission portion 3422 are both made of resin, for example, POM. Note that different materials may be used for the pen tip side portion 3421 and the writing pressure transmission portion 3422. For example, the pen tip side portion 3421 may be made of POM, and the writing pressure transmission portion 3422 may be made of elastic resin or elastic hard rubber.

  The pen tip side portion 3421 includes a tip end portion 3421a serving as a pen tip and an insertion portion 3421b inserted into the pipe portion 341A. In this example, the tip portion 3421a of the pen tip side portion 3421 is configured such that the outer diameter thereof is selected to be substantially equal to the outer diameter of the pipe portion 341A, and the tip has a bullet-shaped curved surface. Further, the insertion portion 3421b of the pen tip side portion 3421 is configured to have an outer diameter slightly smaller than the inner diameter of the hollow portion 341Aa of the pipe portion 341A, and the insertion portion 3421b includes a hollow portion of the pipe portion 341A. A bulging portion 3421c having a diameter equal to or slightly larger than the inner diameter of 341Aa is formed.

  Then, as shown in FIG. 6B, the insertion portion 3421b of the pen tip side portion 3421 is press-fitted and inserted into the hollow portion 341Aa of the pipe portion 341A at the bulging portion 3421c portion, so that the pen tip side portion 3421 is inserted. Are coupled and locked to the pipe portion 341A. In addition, by pulling out the pen tip side portion 3421 from the pipe portion 341A, the coupling between the two can be released.

  In this example, the writing pressure transmission part 3422 of the core 34A includes a fitting part 3422a that fits the writing pressure detection part 35 and an insertion part 3422b that is inserted into the pipe part 341A. In this example, the fitting portion 3422a of the writing pressure transmission portion 3422 is selected so that the outer diameter thereof is substantially equal to the outer diameter of the pipe portion 341A, and the tip is fitted to the writing pressure detection portion 35. Configured as follows. Further, the insertion portion 3422b of the writing pressure transmission portion 3422 is configured to have an outer diameter slightly smaller than the inner diameter of the hollow portion 341Aa of the pipe portion 341A, and the insertion portion 3422b includes a hollow portion of the pipe portion 341A. A bulging portion 3422c having a diameter equal to or slightly larger than the inner diameter of 341Aa is formed.

  Then, as shown in FIG. 6B, the pen pressure transmitting portion 3422 is inserted by inserting the insertion portion 3422b of the pen pressure transmitting portion 3422 into the hollow portion 341Aa of the pipe portion 341A at the bulging portion 3422c. Are coupled and locked to the pipe portion 341A. Note that the writing pressure transmission part 3422 can be released from the pipe part 341A by releasing the coupling between them.

  As described above, the core body 34A of this example is configured by inserting the pen tip side portion 3421 and the writing pressure transmission portion 3422 into the pipe portion 341A and locking them as shown in FIG. 6B. Configured. Therefore, as shown in FIG. 6B, in the core body 34A of this example, the center core portion 342A is composed of the pen tip side portion 3421, the writing pressure transmission portion 3422, and the air 3423 therebetween. It can have the composition which becomes.

  Then, the core body 34A of this example is inserted through the through hole 32d of the ferrite core 32 in the same manner as the core body 34 described above, and the fitting portion 3422a of the writing pressure transmission portion 3422 becomes the writing pressure detection portion 35. The tip part 3421a of the pen tip side part 3421 and a part of the pipe part 341A protrude from the ferrite core 32 and are attached to the electronic pen 1. Therefore, even when the core 34A is used, the electronic pen 1 instructs the position detection sensor to position using the electromagnetic induction method in the same manner as described above.

<Second other example of core>
FIG. 7 is a diagram illustrating a configuration example of a second other example of the core body that can be used in the electronic pen 1 of the first embodiment. The second other example of the core has a configuration of a felt pen as a writing instrument.

  FIG. 7 is a cross-sectional view for explaining a configuration example of the core body 34B of the second other example. Also in the core body 34B of this example, the pipe portion 341B having the same configuration as the pipe portion 341 of the example of the first embodiment described above is used. In the core body 34B of this example, the middle core portion 342B is separated into a pen tip side portion 3424 and a writing pressure transmission portion 3425 as shown in FIG.

  In this example, the pen tip side portion 3424 is formed of a felt having a diameter substantially equal to the diameter of the hollow portion 341Ba of the pipe portion 341B. Then, as shown in FIG. 7, a part of the pen tip side portion 3424 is inserted into the hollow portion 341Ba of the pipe portion 341B, and the pen tip side portion 3424 is locked to the pipe portion 341B. Also in this case, although not shown in FIG. 7, a bulging portion is formed in a portion to be inserted into the hollow portion 341B of the pipe portion 341B of the pen tip side portion 3424, and the pen tip side portion 3424 is attached to the pen tip side portion 3424. The pipe portion 341B can be inserted by being press-fitted into the hollow portion 341B.

  Moreover, the writing pressure transmission part 3425 is comprised with resin, is comprised similarly to the above-mentioned writing pressure transmission part 3422 of 34 A of core bodies, and is provided with the fitting part 3425a and the insertion part 3425b. In FIG. 7, although not shown, the insertion portion 3425 b of the writing pressure transmission portion 3425 is provided with a bulging portion similar to the bulging portion 3422 c of the writing pressure transmission portion 3422. Then, in the same manner as the writing pressure transmission portion 3422 of the core 34A shown in FIG. 6 described above, the insertion portion 3425b of the writing pressure transmission portion 3425 is inserted into the hollow portion 341Ba of the pipe portion 341B, and the pipe portion 341B. On the other hand, the writing pressure transmission part 3425 is locked.

  In the core body 34B of this example, a gel-like ink material 3426 for a felt pen is loaded between the pen tip side portion 3424 and the writing pressure transmission portion 3425 of the pipe portion 341B. Therefore, as shown in FIG. 7, the core part 342B of the core body 34B in this example has a configuration including a pen tip side part 3424, a writing pressure transmission part 3425, and a gel-like ink member 3426 therebetween. It will have.

  Then, the core body 34B of this example is inserted through the through hole 32d of the ferrite core 32 in the same manner as the above-described core body 34A, and the fitting portion 3425a of the writing pressure transmission portion 3425 becomes the writing pressure detection portion 35. The tip part 3424a of the pen tip side part 3424 and a part of the pipe part 341B protrude from the ferrite core 32 and are attached to the electronic pen 1. Accordingly, even when the core 34B is used, the electronic pen 1 instructs the position detection sensor to position using the electromagnetic induction method in the same manner as described above.

  Furthermore, in the core body 34B of the second other example, the gel-like ink member 3426 penetrates to the tip portion 3424a of the pen tip side portion 3424 made of felt. Therefore, when using the electronic pen 1 equipped with the core 34B, the tip 3424a of the pen tip side 3424 is brought into contact with the paper to draw a trajectory, thereby drawing characters and pictures in the same way as a so-called felt pen. can do. Therefore, when a paper is placed on the position detection sensor and a character or picture is drawn by the electronic pen 1, the drawn character or picture remains on the paper and the drawn character or picture trajectory is detected by the position detection sensor. The coordinate data is obtained by the position detection device.

  In the example of FIG. 7, the pen pressure transmission unit 3425 is attached to the core body 34B, but the side opposite to the pen tip side part 3424 of the pipe portion 341B of the core body 34B is connected to the pen pressure transmission unit. The writing pressure transmission unit 3425 can also be omitted by using both.

<Third other example of core>
FIG. 8 is a diagram illustrating a configuration example of a third other example of the core body that can be used in the electronic pen 1 of the first embodiment. A third other example of the core has a configuration of a ballpoint pen as a writing instrument.

  FIG. 8 is a cross-sectional view for explaining a configuration example of the core body 34C of the third other example. Also in the core body 34C of this example, the pipe portion 341C having the same configuration as the pipe portion 341 of the above-described example of the first embodiment is used as the pipe portion. In the core body 34B of this example, the pen tip side portion 3427 has the same configuration as the pen tip of the ballpoint pen, and includes a tip portion 3427a and an insertion portion 3427b, and a ball 3427c is provided at the tip of the tip portion 3427a. Embedded.

  The insertion portion 3427b of the pen tip side portion 3427 has a diameter that is substantially the same as or slightly smaller than the diameter of the hollow portion 341Ca of the pipe portion 341C, and has a bulging portion (not shown in FIG. 8). The insertion portion 3427b is inserted into the hollow portion 341Ca of the pipe portion 341C, and the pen tip side portion 3427 is locked to the pipe portion 341C.

  The hollow portion 341Ca of the pipe portion 341C is filled with ink liquid 3428 for ballpoint pen. In the core body 34 </ b> C of this example, the side opposite to the pen tip side part 3427 of the pipe part 341 </ b> C is configured to also serve as the writing pressure transmission part 3429. It should be noted that, of course, a configuration in which a pen pressure transmission unit similar to the pen pressure transmission unit 3425 of the core body 34B illustrated in FIG. 7 is fitted and provided on the opposite side of the pipe portion 341C from the pen tip side portion 3427 may be used.

  As shown in FIG. 8, the core part 342C of the core body 34C in this example has a configuration including a pen tip side part 3427, a writing pressure transmission part 3429, and a ballpoint pen ink liquid 3428 therebetween. It becomes.

  The core body 34C of this example is inserted through the through hole 32d of the ferrite core 32 in the same manner as the above-described core body 34A, and the writing pressure transmission unit 3429 is fitted to the writing pressure detection unit 35. The distal end portion 3427 a of the front side portion 3427 and a part of the pipe portion 341 C are in a state of protruding from the ferrite core 32 and attached to the electronic pen 1. Therefore, even when the core 34C is used, the electronic pen 1 instructs the position detection sensor to position using the electromagnetic induction method in the same manner as described above.

  Further, in the core body 34 </ b> C of the third other example, the ball-point pen ink liquid 3428 penetrates to the ball 3427 c of the tip end portion 3427 a of the pen tip side portion 3427. Therefore, when using the electronic pen 1 equipped with the core 34C, the tip 3427a of the pen tip side 3427 is brought into contact with the paper to draw a locus, thereby drawing characters and pictures in the same manner as the ballpoint pen. Can do. Therefore, when a paper is placed on the position detection sensor and a character or picture is drawn by the electronic pen 1, the drawn character or picture remains on the paper and the drawn character or picture trajectory is detected by the position detection sensor. The coordinate data is obtained by the position detection device.

  In the cores 34A to 34C of the first to third other examples described above, the pen pressure transmission units 3422, 3425, and 3429 on the side opposite to the pen tip side of the center cores 342A to 342C are pen pressure detections. Although the fitting part fitted to the part 35 is comprised, the pressing member of another member fitted to the writing pressure detection part 35 is provided, and the writing pressure transmission parts 3422, 3425, and 3429 of the center core parts 342A-342C are provided. May be configured to be fitted to the pressing member and transmit the writing pressure applied to the tip of the core body 34 to the writing pressure detection unit 35 via the pressing member.

[Second Embodiment]
The above is a case where the present invention is applied to an electromagnetic induction type electronic pen. However, the present invention can also be applied to an active electrostatic pen that is an example of a capacitive electronic pen. In the electronic pen according to the second embodiment described below, the coil wound around the ferrite core is part of a charging circuit that charges the power source of the signal transmission circuit.

  FIG. 9 is a diagram illustrating an internal structure of a position indicating unit of an electrostatic stylus pen 1D that is an example of the electronic pen according to the second embodiment. FIG. 10 is a circuit configuration diagram of an electrostatic stylus pen 1D which is an example of the electronic pen according to the second embodiment. In FIG. 9 and FIG. 10, the same components are indicated by the same reference numerals.

  In the electrostatic stylus pen 1D of the second embodiment, the structure of the core body 34D and the structure of the pen tip side including the ferrite core 32D are the first embodiment described with reference to FIGS. It is the same as the form. However, the electrostatic stylus pen 1D of the second embodiment is configured not to use the electronic pen main body.

  That is, the ferrite core 32D is provided with a through hole 32Da in the axial direction, and a coil 31D is partially wound around the ferrite core 32D. Similarly to the first embodiment, the ferrite core 32D has a coil winding portion 32Da around which the coil 31D is wound in the axial direction, and the first coil non-coil is formed on the pen tip side. A winding portion 32Db is formed, and a second coil non-winding portion 32Dc is formed on the side opposite to the pen tip side.

  In the second embodiment, the core body 34D has the same configuration as the core body 34 shown in FIGS. 3 and 4, but has a conductive configuration. That is, although detailed illustration is omitted, the core body 34 </ b> D has the same configuration as the pipe section 341 of the core body 34, and is similar to the pipe section made of conductive metal and the core section 342 of the core body 34. And a conductor, for example, a core part made of a hard resin mixed with a conductive metal or conductive powder. Therefore, in the second embodiment, the core body 34D has conductivity, and therefore, in the following description, the core body 34D is referred to as an electrode core 34D.

  The electrode core 34D is inserted into the penetrating hole 32Dd of the ferrite core 32D and fitted to the writing pressure detection unit 35D in the same manner as in the first embodiment. The writing pressure detection unit 35D is provided in a cylindrical body portion that is connected to the ferrite core 32D in the casing of the electrostatic stylus pen 1D, and is configured as a variable capacitor. The electrode core 34D is configured integrally with a signal sending electrode and a pressing body fitted to the writing pressure detection unit 35D which is a configuration of a variable capacitor.

  Although not shown in FIG. 9, a printed circuit board on which a signal transmission circuit that sends out to the outside through the electrode core 34 </ b> D is disposed in the casing of the electrostatic stylus pen 1 </ b> D. When the electrode core 34D is fitted to the writing pressure detection unit 35D, the electrode core 34D is connected to the signal transmission circuit of the printed circuit board by the connection line 39. Next, the circuit configuration of the electrostatic stylus pen 1D will be described.

  In FIG. 10, 51 is an electric double layer capacitor, 52 is a rectifying diode, 53 is a voltage conversion circuit, and 54 is an oscillation circuit constituting the signal transmission circuit of this example. As shown in FIG. 10, in this example, one end of the coil 31D is connected to the anode of the diode 52, and the other end is grounded (GND). One end of the electric double layer capacitor 51 is connected to the cathode of the diode 52, and the other end is grounded.

  The electrode core 34D passes through the through hole 32Dd of the ferrite core 32D around which the coil 31D is wound, and is physically coupled (engaged) with the writing pressure detection unit 35D constituting the variable capacitor, and the electrode core 34D. And the writing pressure detector 35D constituting the variable capacitor are electrically connected to the connection line 39 at the joint. The connection line 39 electrically connects the electrode core 34D and the oscillation circuit 54. Therefore, the pressure (writing pressure) applied to the electrode core 34D by the physical coupling between the electrode core 34D and the writing pressure detection unit 35D constituting the variable capacitor is transmitted to the writing pressure detection unit 35D and connected. A transmission signal from the oscillation circuit 54 is transmitted from the electrode core 34D via the line 39.

  The oscillation circuit 54 generates a signal whose frequency changes according to the capacitance of the variable capacitor of the writing pressure detection unit 35D, and supplies the generated signal to the electrode core 34D. A signal from the oscillation circuit 54 is radiated as an electric field based on the signal from the electrode core 34D. The oscillation circuit 54 is configured by an LC oscillation circuit that uses resonance by a coil and a capacitor, for example. In the tablet that detects the coordinate position of the electrostatic stylus pen 1D as an example of the electronic pen of this embodiment, the writing pressure applied to the electrode core 34D can be obtained from the frequency of this signal.

  The voltage conversion circuit 53 converts the voltage stored in the electric double layer capacitor 51 into a constant voltage and supplies it as a power source for the oscillation circuit 54. The voltage conversion circuit 53 may be a step-down type that is lower than the voltage at both ends of the electric double layer capacitor 51, or may be a step-up type that is higher than the voltage at both ends of the electric double layer capacitor 51. good. Further, it may be a step-up / step-down type that operates as a step-down circuit when the voltage across the electric double layer capacitor 51 is higher than the constant voltage and operates as a step-up circuit when the voltage is lower than the constant voltage.

  When the electrostatic stylus pen 1D of this embodiment is attached to a charger (not shown), an induced electromotive force is generated in the coil 31D by an alternating magnetic field generated by the charger, and the electric double layer capacitor is connected via the diode 52. 51 is charged.

  When the electrostatic stylus pen 1D of this embodiment normally operates (when the charging operation is not performed), the coil 31D is at a fixed potential (in this example, the ground potential (GND)), and therefore around the electrode core 34D. Acts as a shield electrode provided. Note that the fixed potential of the coil 31D when the electrostatic stylus pen 1D normally operates is not limited to the ground potential, but may be a positive potential of the power source, or an intermediate between the positive potential of the power source and the ground potential. It may be a potential of.

According to the electrostatic stylus pen 1D that is an example of the electronic pen of the second embodiment, the electrode core 34D is disposed so as to penetrate the charging coil 31D.
The pen pressure applied to the electrode core 34D is transmitted to the pen pressure detection unit 35D without being obstructed.
The cross-sectional area of the charging coil 31D can be increased, so that charging can be performed quickly and efficiently.
The charging coil 31D and the electrode core 34D can be arranged in a narrow space, and the electrostatic stylus pen can be made thin.
There is an effect.

  Further, according to the electrostatic stylus pen 1D which is an example of the electronic pen of the above-described second embodiment, the charging coil 31D acts as a shield electrode during normal operation, not during charging operation. Holding the housing 2 of the stylus pen 1D by hand does not affect the signal output from the electrode core 34D.

  Further, according to the electrostatic stylus pen 1D which is an example of the electronic pen of the second embodiment described above, the coil 31D for non-contact charging is provided around the electrode core 34D. An electrostatic stylus pen with good operability can be realized.

  FIG. 11 shows a position detection device 700 that receives a signal from an electrostatic stylus pen 1D that is an example of the electronic pen according to the second embodiment, detects a position on the sensor, and detects writing pressure. It is a block diagram for demonstrating.

As shown in FIG. 11, the position detection device 700 of this embodiment includes a sensor 710 and a pen detection circuit 720 connected to the sensor 710. The sensor 710 is formed by laminating a first conductor group 711, an insulating layer (not shown), and a second conductor group 712 in order from the lower layer side, although a cross-sectional view is omitted in this example. is there. The first conductor group 711, for example, separates a plurality of first conductors 711Y ₁ , 711Y ₂ ,..., 711Y _m (m is an integer of 1 or more) extending in the lateral direction (X-axis direction) from each other by a predetermined distance. Are arranged in parallel in the Y-axis direction.

The second conductor group 712 extends in a direction intersecting with the extending direction of the first conductors 711Y ₁ , 711Y ₂ ,..., 711Y _m , in this example, the orthogonal vertical direction (Y-axis direction). The plurality of second conductors 712X ₁ , 712X ₂ ,..., 712X _n (n is an integer of 1 or more) are spaced apart from each other by a predetermined distance and arranged in parallel in the X-axis direction.

  As described above, the sensor 710 of the position detection device 700 detects the position indicated by the electrostatic stylus pen 1D using the sensor pattern formed by intersecting the first conductor group 711 and the second conductor group 712. It has a configuration to do.

In the following description, when there is no need to distinguish between the first conductors 711Y ₁ , 711Y ₂ ,..., 711Y _m , the conductors are referred to as first conductors 711Y. Similarly, when there is no need to distinguish between the second conductors 712X ₁ , 712X ₂ ,..., 712X _n , the conductors are referred to as second conductors 712X.

  The pen instruction detection circuit 720 includes a selection circuit 721 serving as an input / output interface with the sensor 710, an amplification circuit 722, a bandpass filter 723, a detection circuit 724, a sample hold circuit 725, and an AD (Analog to Digital). A conversion circuit 726 and a control circuit 727 are included.

  The selection circuit 721 selects one conductor 711 </ b> Y or 712 </ b> X from the first conductor group 711 and the second conductor group 712 based on the control signal from the control circuit 727. The conductor selected by the selection circuit 721 is connected to the amplification circuit 722, and the signal from the electrostatic stylus pen 1D is detected by the selected conductor and amplified by the amplification circuit 722. The output of the amplifier circuit 722 is supplied to a band pass filter 723, and only the frequency component of the signal transmitted from the electrostatic stylus pen 1D is extracted.

  The output signal of the bandpass filter 723 is detected by the detection circuit 724. The output signal of the detection circuit 724 is supplied to the sample hold circuit 725, sampled and held at a predetermined timing by the sampling signal from the control circuit 727, and then converted into a digital value by the AD conversion circuit 726. Digital data from the AD conversion circuit 726 is read and processed by the control circuit 727.

  The control circuit 727 operates to send control signals to the sample hold circuit 725, the AD conversion circuit 726, and the selection circuit 721, respectively, according to a program stored in the internal ROM. The control circuit 727 calculates the position coordinates on the sensor 710 indicated by the electrostatic stylus pen 1D from the digital data from the AD conversion circuit 726, and calculates the writing pressure detected by the writing pressure detection unit 35D. Try to detect.

That is, for example, the control circuit 727 _first supplies a selection signal for sequentially selecting the second conductors 712X _{1 to} 712X _n to the selection circuit 721, and AD conversion is performed when each of the second conductors 712X _{1 to} 712X _n is selected. Data output from the circuit 726 is read as a signal level. If all the signal levels of the second conductors 712X _{1 to} 712X _n have not reached the predetermined value, the control circuit 727 determines that the electrostatic stylus pen 1D is not on the sensor 710, and the second The control of sequentially selecting the conductors 712X _{1 to} 712X _n is repeated.

When a signal having a level equal to or higher than a predetermined value is detected from any _{one of} the second conductors 712X _{1 to} 712X _n , the control circuit 720 determines the number of the second conductor 712X in which the highest signal level is detected and the number of the second conductor 712X. A plurality of peripheral second conductors 712X are stored. Then, the control circuit 727 controls the selection circuit 721 to sequentially select the first conductors 711Y _{1 to} 711Y _m and read the signal level from the AD conversion circuit 726. At this time, the control circuit 727 stores the numbers of the first conductor 711Y in which the highest signal level is detected and the plurality of first conductors 711Y around it.

  Then, the control circuit 727 stores the number of the second conductor 712X and the number of the first conductor 711Y in which the largest signal level is detected and a plurality of second numbers around it, which are stored as described above. The position on the sensor 710 indicated by the electrostatic stylus pen 1D is detected from the conductor 712X and the first conductor 711Y.

  The control circuit 727 also detects the frequency of the signal from the AD conversion circuit 726, and detects the writing pressure value detected by the writing pressure detection unit 35D from the detected frequency. That is, as described above, the oscillation frequency of the oscillation circuit 54 of the electrostatic stylus pen 1D is a frequency corresponding to the capacitance of the variable capacitor configured by the writing pressure detection unit 35D. The control circuit 727 includes, for example, information on a correspondence table between the oscillation frequency of the oscillation circuit 54 of the electrostatic stylus pen 1D and the pen pressure value, and detects the pen pressure value from the information on the correspondence table.

  In the second embodiment described above, the electrostatic stylus pen 1D converts the writing pressure detected by the writing pressure detector 35D into a frequency and supplies it to the electrode core 34D. The signal attribute to be generated is not limited to the frequency, and the writing pressure may be made to correspond to the phase of the signal, the number of signal interruptions, and the like.

[Modification of Second Embodiment]
The core 34D of the electrostatic stylus pen 1D according to the above-described embodiment is configured in the same manner as the core 34 shown in FIGS. 3 and 4, but is shown in FIGS. 6, 7, and 8. It can also be set as the structure similar to core body 34A, 34B, 34C of another example.

  When the core body 34D has a configuration similar to that of the core bodies 34A and 34B, the pen tip side portion and the writing pressure transmission portion are configured separately, but the pen tip side portion and the writing pressure The transmission portion is made of a conductive member such as a hard resin mixed with conductive metal or conductive powder, for example, and is inserted and fitted into a pipe portion made of conductive metal. If the core body 34D has the same configuration as the core body 34C, the writing pressure transmission part is also used as a pipe part made of a conductive metal. Needless to say, you don't have to.

  In the second embodiment described above, a rechargeable electric double layer capacitor is used as a power source of the signal transmission circuit, and a coil wound around a ferrite core is used as an element for receiving charging energy. However, a charging electrode is formed on the casing of the electrostatic stylus pen 1D, and a charging element such as an electric double layer capacitor is charged through the electrode, or a replaceable secondary battery is used as a power source for the signal transmission circuit. You may make it do. In that case, the electrostatic stylus pen 1D does not need to use a coil wound around the ferrite core, and the core body 34D does not have to be configured to insert the through hole of the ferrite core.

  In the description of the second embodiment, the signal transmission circuit is configured as an oscillation circuit. However, the signal transmission circuit is a circuit that modulates an oscillation signal by ASK (Amplitude Shift Keying) or generates a spreading code. Also good.

[Other Embodiments or Modifications]
In the above-described embodiment, the writing pressure detection unit uses a variable capacitor that varies the capacitance according to the writing pressure. However, if the changing element changes the resonance frequency of the resonance circuit, the writing pressure detection unit Needless to say, the resistance value may be variable.

  In the above-described embodiment, the electronic pen main body is provided with the writing pressure detection unit. However, instead of the writing pressure detection unit, the electronic pen main body is turned on according to the pressure applied to the core of the electronic pen main body. The switch may be configured such that when the switch is turned on, the resonance circuit operates, or the oscillation circuit starts to oscillate. In addition, a threshold is set for the pressure detected by the pen pressure detection unit, and the resonance circuit operates when the pressure detected by the pen pressure detection unit exceeds the threshold, or the oscillation circuit oscillates. Or may be configured to start.

  Further, in the above-described embodiment, the electronic pen main body has the same dimensions as the replacement core of a commercially available ballpoint pen, and compatibility between the casing of the electronic pens 1 and 1M and the casing of the commercially available ballpoint pen can be achieved. However, it is a matter of course that a thin electronic pen main body can be configured without considering compatibility with a commercially available ballpoint pen replacement core.

  Further, in the first embodiment described above, the electronic pen main body is configured to be inserted into and removed from the housing in a knock manner using the knock cam mechanism, but is not limited to such a knock type, Simply, an electronic pen having a configuration in which the main body of the electronic pen is housed in a housing may be used.

  In the electronic pens of the first to second embodiments described above, the pen pressure detectors 35 and 35A detect the change in the resonance frequency and the change in the frequency of the oscillation signal in the resonance circuit including the coil 31 and the capacitor. Although the writing pressure information is transmitted to the position detection device, the information transmitted to the position detection device as a change in the resonance frequency or the frequency of the oscillation signal is not limited to the writing pressure information. For example, the inclination detected by the inclination detection sensor that detects the inclination of the electronic pen main body with respect to the sensor surface (instruction input surface) may be transmitted as a change in the resonance frequency or a change in the frequency of the oscillation signal.

  In the above description, in the second embodiment, the cartridge type configuration using the electronic pen main body is not used. However, in the second embodiment, the cartridge type using the electronic pen main body is also used. It is good also as a structure. Conversely, in the first embodiment, the cartridge type configuration using the electronic pen main body is used. However, the electronic pen main body is also used in the electromagnetic induction type electronic pen of the first embodiment. A configuration that is not a cartridge type configuration may be used.

DESCRIPTION OF SYMBOLS 1,1D ... Electronic pen, 2 ... Housing | casing, 3 ... Electronic pen main-body part, 4 ... Knock cam mechanism, 6 ... Replacement core of commercially available ball-point pen, 31 ... Coil, 32, 32D ... Ferrite core, 33 ... Cylindrical body part , 34, 34A, 34B, 34C, 34D ... core body, 35, 35D ... writing pressure detection unit, 341 ... pipe portion, 342 ... middle core portion, 342a ... one end portion (pen nib) of the middle core portion 342, 342b... The other end of the core portion 342 (writing pressure transmission portion)

Claims (15)

A cylindrical housing having an opening on one side;
A core body housed in the housing and having a tip protruding from the opening;
A pen pressure detection unit for detecting a pen pressure applied to the core;
Have
The core is
It has a core part and a pipe part,
The middle core portion is inserted into the hollow portion of the pipe portion, and at least a tip portion is locked to the pipe portion in a state of protruding from one end portion in the axial direction of the pipe portion,
When the tip of the core is the tip of the core, and when the tip of the core protrudes from the opening of the housing, a part of the pipe also protrudes from the opening. ,
A writing pressure applied to the tip of the central core portion is determined according to the applied writing pressure, and the core body has an axial core of the cylindrical casing with the side surface of the pipe portion facing the opening. An electronic pen that is slidable in a direction so as to be transmitted to the writing pressure detection unit through the pipe unit. The other end portion of the pipe portion of the core body in the axial direction protrudes from the end portion of the pipe portion in the axial direction, and transmits the writing pressure to the writing pressure detector. 2. The electronic pen according to claim 1, wherein a pen pressure transmission portion made of a material different from the pipe portion is provided, and the center portion includes the tip portion and the pen pressure transmission portion. The electronic pen according to claim 2, wherein the central core portion is a member that integrally includes the tip portion and the writing pressure transmission portion. 3. The electronic pen according to claim 2, wherein the center portion includes air, gel, or liquid between the tip portion and the writing pressure transmission portion. The electronic pen according to claim 1, wherein the pipe portion is made of a member having a rigidity higher than that of the core portion.   The pipe part is made of metal. 2. The electronic pen according to claim 1, wherein the core portion is insertable and removable with respect to the pipe portion. The electronic pen according to claim 4, wherein the tip portion and / or the writing pressure transmission portion is insertable / removable with respect to the pipe portion. The electronic pen according to any one of claims 2 to 4, wherein the distal end portion and / or the writing pressure transmission portion of the central core portion is made of a resin material. In the casing, a magnetic core around which a coil is wound is provided in the vicinity of the opening, the through hole is formed in the magnetic core, and the core is formed of the magnetic core. The pen pressure is applied to the tip of the core through the through hole, the tip protruding from the opening, and the side opposite to the tip of the core protruding through the magnetic core. The electronic pen according to claim 1, wherein the electronic pen is transmitted to the writing pressure detection unit via the pipe unit. The electronic pen according to claim 10, wherein when the tip of the core body protrudes from the opening, a part of the magnetic core also protrudes from the opening. The electronic pen according to claim 11, wherein the magnetic core protruding from the opening is a portion where the coil is not wound. 13. The tip of the core that protrudes from the through hole of the magnetic core is composed of the tip of the middle core and a part of the pipe. 13. Electronic pen. A resonance circuit in which a capacitor is connected in parallel to the coil wound around the magnetic core, and the position is indicated by being coupled to a position detection sensor by an electromagnetic induction method by the resonance circuit. The electronic pen according to any one of claims 10 to 13. Equipped with a signal transmission circuit,
The pipe part is made of a conductive metal, and the tip part of the core part that constitutes the tip of the core body is made of a conductive material.
The electronic pen according to claim 1, wherein a signal from the signal transmission circuit is transmitted through a tip portion of the pipe portion and the core portion.

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