Patent Description:
As an electronic pen of a capacitive system, an electronic pen of what is called an active capacitive system that carries out transfer of signals (interaction) through electric field coupling with a position detecting sensor of a position detecting device to allow detection of a position indicated by the electronic pen by the position detecting sensor has been favorably used.

In this kind of electronic pen of the active capacitive system, a power supply circuit and a signal transmitting circuit using a primary cell or secondary cell are incorporated. In addition, a core body is composed of a conductor, and the electronic pen transmits a signal from the signal transmitting circuit from the core body of the conductor to the position detecting sensor by capacitive coupling (for example, <CIT>).

<CIT>, which constitutes prior art pursuant to Art. <NUM>(<NUM>) EPC, discloses an electronic pen cartridge including a pen tip part that protrudes to the external through an opening of an electronic pen casing or is made capable of protruding to the external through the opening.

<CIT> discloses another example of an electronic pen comprising a cartridge including a pen tip.

Incidentally, due to preference for size reduction in recent years, requests for size reduction have become stronger also regarding portable electronic equipment. Furthermore, the electronic pen has come to be used with a position detecting sensor mounted in this kind of small-size electronic equipment, and ones with a thinner shape have been required.

Moreover, recently, the electronic pen has been regarded as an extension of a writing material, and there has also been a demand for the internal configuration thereof to be modularized and be allowed to be treated similarly to a replacement core (refill or cartridge) of a ballpoint pen. Hereinafter, in this specification, what is configured to be replaceable like a replacement core of a ballpoint pen through modularization and integration of internal constituent parts of an electronic pen will be referred to as an electronic pen main unit.

In a case of attempting to configure the electronic pen of the active capacitive system with such an electronic pen main unit housed in the casing of the electronic pen, supply means of power to the signal transmitting circuit housed in the electronic pen main unit becomes a problem. That is, the electronic pen main unit in this case will have a very thin shape, and it is difficult to dispose a large-size primary cell in the electronic pen main unit. Even if it is possible to mount a primary cell in the electronic pen main unit, its battery capacity is small, requiring frequent replacement and causing unbearable troublesomeness. Thus, a rechargeable small-size power storage element or secondary cell needs to be disposed in the electronic pen main unit and be charged from the external. However, how to carry out the charging is a problem.

Furthermore, in the electronic pen, there is also an electronic circuit component that needs to be disposed on the casing of the electronic pen in a state of being operable by a user, such as a side switch, and how to implement an electrical connection between the electronic circuit component and an electronic circuit of the electronic pen main unit is also a problem.

Moreover, in a case of configuring an electronic pen with use of such an electronic pen main unit, it is also essential to protrude the tip part of the electronic pen main unit from an opening of the casing of the electronic pen to the external only when the electronic pen is used similarly to, for example, a knock-type ballpoint pen, in order to protect the thin tip part. However, in a case in which the electronic pen main unit moves in the axial center direction in the casing of the electronic pen in that way, how to make an electrical connection between the electronic pen main unit like the above-described one and the electronic circuit component disposed on the casing of the electronic pen is a large problem.

This invention intends to provide an electronic pen and an electronic pen main unit that are enabled to solve the above problems.

In order to solve the above-described problems, provided is an electronic pen main unit that is fitted to a fitting part disposed in a casing of an electronic pen in which a pen tip side that is one end side in an axial center direction is made to be an opening and is housed in a state of being movable in a hollow part of the casing by a movement mechanism that moves the fitting part in the axial center direction of the casing. The electronic pen main unit is characterized by including a pen tip part including an electrically-conductive core body allowed to protrude to external through the opening by being moved by the movement mechanism, a main body tubular part to which the pen tip part is joined on the pen tip side in the axial center direction and that houses an electronic circuit including a signal generating circuit that generates a signal to be sent out to the external through the core body, and a rear-end-part connector that is disposed at a rear end part of the main body tubular part on a side opposite to the pen tip part in the axial center direction, includes a terminal connected to the electronic circuit, and is joined to a connector for joining disposed at the fitting part of the casing.

Furthermore, provided is an electronic pen that has a tubular casing in which an opening is made on one end side in the axial center direction that is the pen tip side and in which at least one electronic pen main unit is housed in the tubular casing. The electronic pen is characterized by including a fitting part to which a rear end part side of the electronic pen main unit on the side opposite to the pen tip side is fitted, and a movement mechanism that moves the fitting part in the axial center direction of the casing, in which the fitting part includes a connector for joining including a terminal electrically connected to an electronic circuit component disposed on the casing, and the electronic pen main unit includes a pen tip part including an electrically-conductive core body allowed to protrude to the external through the opening through movement of the fitting part by the movement mechanism, a main body tubular part to which the pen tip part is joined on the pen tip side in the axial center direction and that houses an electronic circuit including a signal generating circuit that generates a signal to be sent out to the external through the core body, and a rear-end-part connector that is disposed at a rear end part of the main body tubular part on the side opposite to the pen tip part in the axial center direction, includes a terminal connected to the electronic circuit, and is joined to the connector for joining at the fitting part of the casing.

The electronic pen main unit with the above-described configuration is fitted to the fitting part that moves by the movement mechanism of the electronic pen and moves in the axial center direction in the hollow part of the casing of the electronic pen, and the pen tip part thereof is configured to be capable of protruding to the external from the opening of the casing.

Furthermore, the rear-end-part connector connected to the electronic circuit disposed inside the electronic pen main unit is disposed at the rear end part of the electronic pen main unit on the side opposite to the pen tip side. Moreover, at the fitting part of the casing of the electronic pen, the connector for joining to which electronic circuit components such as an electrode for charging and a side switch disposed on the casing of the electronic pen are connected is disposed.

Therefore, the rear-end-part connector and the connector for joining are joined when the rear end part of the electronic pen main unit is fitted to the fitting part of the casing of the electronic pen. Due to this, for example, a charging current supplied from the external to the electrode for charging is supplied to a power storage element included in the electronic circuit disposed inside the electronic pen main unit through the connector for joining and the rear-end-part connector, and the power storage element is charged. Furthermore, for example, a terminal of the side switch is connected to the electronic circuit disposed inside the electronic pen main unit through the connector for joining and the rear-end-part connector. This allows the electronic circuit to recognize a state of the side switch.

In the above-described configuration, the connector for joining is disposed at the fitting part moved by the movement mechanism, and the rear-end-part connector is disposed at the rear end part of the electronic pen main unit fitted to this fitting part. Therefore, the electronic pen main unit has a characteristic that the electrical connection is always secured even when the electronic pen main unit moves in the axial center direction in the casing of the electronic pen.

Embodiments of the electronic pen and the electronic pen main unit according to this invention will be described below with reference to the drawings.

An electronic pen of a first embodiment has a configuration in which an electronic pen main unit made to have a configuration of a cartridge type is housed in a tubular casing of the electronic pen attachably and detachably.

Incidentally, in electronic pens of the active capacitive system of recent years, an electronic pen of a bidirectional communication type that receives a signal from the side of a position detecting sensor that detects a position indicated by the electronic pen and transmits a signal of a format based on a request of the received signal has also been developed.

In this kind of electronic pen of the bidirectional communication type, the position of a receiving part for receiving the signal from the position detecting sensor is important. In a case of an electronic pen of the capacitive system, the signal transmitted from the position detecting sensor is what is based on an electric field that can be received by capacitive coupling, and the reaching distance of the signal is very short. Thus, the receiving part of the electronic pen of the bidirectional communication type should be disposed at a position close to the pen tip so that the signal from the position detecting sensor can be received with high intensity.

Thus, in the electronic pen of this embodiment, the configuration of the electronic pen main unit is considered to become the optimum configuration as one for the above-described electronic pen of the bidirectional communication type. Specifically, in the embodiment to be described below, a receiving part of a signal from a position detecting sensor is disposed in the electronic pen main unit. This receiving part includes a peripheral electrode composed of a tubular conductor disposed to surround a center electrode in such a manner as to cover the center electrode to the vicinity of the tip part of the center electrode while electrical insulation from the center electrode composed of an electrically-conductive material is taken into consideration.

Furthermore, recently, a technique has been proposed in which the tilt angle with respect to the position detecting sensor surface regarding the electronic pen (angle formed by the axial center direction of the electronic pen and the position detecting sensor surface; hereinafter abbreviated as a tilt angle of the electronic pen) is detected by a position detecting device and the detected tilt angle is reflected in the thickness of an indication locus (writing trace) of the electronic pen, and so forth. In the electronic pen main unit of the electronic pen of this embodiment, the above-described peripheral electrode is configured to be usable also for detection of a tilt angle of this electronic pen.

Furthermore, in this first embodiment, the peripheral electrode is configured to also play a role as a shield electrode for the center electrode that sends out a signal for position detection.

<FIG> depicts diagrams illustrating configuration examples of the first embodiment of the electronic pen according to this invention. An electronic pen <NUM> of this first embodiment has a configuration of a knock system in which an electronic pen main unit <NUM> is housed in a hollow part 2a of a tubular casing <NUM> (hereinafter, referred to as a pen casing <NUM>) and the pen tip side of the electronic pen main unit <NUM> is caused to protrude and retract from the side of an opening 2b with a diameter R0 on one end side of the pen casing <NUM> in the longitudinal direction by a knock cam mechanism unit <NUM> as an example of the movement mechanism.

<FIG> illustrates the state in which the whole of the electronic pen main unit <NUM> is housed in the hollow part 2a of the pen casing <NUM>, and <FIG> illustrates the state in which the pen tip side of the electronic pen main unit <NUM> protrudes from the opening 2b of the pen casing <NUM> due to the knock cam mechanism unit <NUM>. In the example of <FIG>, the pen casing <NUM> of the electronic pen <NUM> is composed of a transparent synthetic resin and is illustrated to be in the state in which the inside thereof is visible in a see-through manner.

In this embodiment, the pen casing <NUM> and the knock cam mechanism unit <NUM> disposed in the pen casing <NUM> are configured similarly to a well-known, commercially-available knock-type ballpoint pen.

As illustrated in <FIG>, the knock cam mechanism unit <NUM> is given a well-known configuration in which a cam main body <NUM>, a knock bar <NUM>, and a rotor <NUM> are combined. The cam main body <NUM> is formed on the inner wall surface of the tubular pen casing <NUM>. In the knock bar <NUM>, an end part 42a is allowed to protrude from an opening 2c of the pen casing <NUM> on the side opposite to the pen tip side so that knock operation by the user can be accepted. The rotor <NUM> has a fitting part 43a to which the rear end part of the electronic pen main unit <NUM> on the side opposite to the pen tip side is fitted.

However, the fitting part 43a is different from the fitting part of the casing of the knock-type ballpoint pen of a normal writing material in that a configuration of an electrical connection with the electronic pen main unit <NUM> is added to the fitting part 43a. Specifically, as described later, the electronic pen main unit <NUM> internally includes a signal transmitting circuit that generates a signal to be sent out to the position detecting sensor through the center electrode or the peripheral electrode, and a supply voltage needs to be provided to the signal transmitting circuit.

In this embodiment, as described later, the signal transmitting circuit and a power storage element that supplies power to the signal transmitting circuit are disposed inside the electronic pen main unit <NUM>. Furthermore, the power storage element needs to be charged from the external of the electronic pen main unit <NUM>. Thus, a terminal conductor (electrode) connected to the power storage element is disposed at the end part fitted to the fitting part 43a in the electronic pen main unit <NUM> of this embodiment, and a conductor connected to the terminal conductor connected to the power storage element is formed at the fitting part 43a. Only the electrical configuration is added to the configuration of the joined part to the electronic pen main unit <NUM>, and the configuration of this joined part still remains a configuration to which a replacement core of a ballpoint pen is joined and mounted. A configuration example of the end part fitted to the fitting part 43a in the electronic pen main unit <NUM> will be described later together with a configuration example of the fitting part 43a.

Furthermore, at a part of the outer circumferential side surface on the side opposite to the pen tip side, in this example, in the pen casing <NUM>, electrodes 2d and 2e for charging connected to a conductor disposed at the fitting part 43a are formed as illustrated in <FIG>.

Moreover, a side switch <NUM> is disposed at a position on the outer circumferential side surface at which operation is allowed when the user uses the electronic pen <NUM> in the pen casing <NUM>. The side switch <NUM> has a configuration of a push button switch or slide switch and is a well-known one in the electronic pen. Therefore, an example of the detailed structure thereof is omitted here.

In the electronic pen <NUM> of this first embodiment, operation information of the side switch <NUM> is transmitted to the electronic pen main unit <NUM> through the fitting part 43a. The electronic pen main unit <NUM> of this first embodiment sends out this operation information of the side switch <NUM> to the position detecting device in addition to the signal for position detection and writing pressure information. Functions corresponding to this operation information of the side switch <NUM> are set in the position detecting device, and the position detecting device executes processing according to the set functions in accordance with the operation information of the side switch <NUM> received from the electronic pen main unit <NUM>.

Furthermore, in this embodiment, a conductor band 2f is disposed at a position on the outer circumferential side surface grasped by the user at the time of use in the pen casing <NUM>. This conductor band 2f is what is formed of a tubular body composed of an electrically-conductive material such as electrically-conductive rubber, for example, and is disposed to cover a partial outer circumference of the pen casing <NUM> in the axial center direction. In this first embodiment, the conductor band 2f is configured to be connected to an earth electrode of the electronic pen main unit <NUM> through the fitting part 43a. The user grasps the part of this conductor band 2f at the time of use. Due to this, the conductor band 2f and the earth electrode of the electronic pen main unit <NUM> connected thereto (metal pipe part 31a of a main body tubular part <NUM> to be described later is also connected) are connected to the ground (grounded) through the human body of the user.

In the electronic pen <NUM> with the above configuration, when the end part 42a of the knock bar <NUM> is pressed down in the state of <FIG>, the electronic pen main unit <NUM> is locked to the state of <FIG> in the pen casing <NUM> by the knock cam mechanism unit <NUM>, which makes the state in which the pen tip side of the electronic pen main unit <NUM> protrudes from the opening 2b of the pen casing <NUM>. Then, when the end part 42a of the knock bar <NUM> is pressed down again from this state of <FIG>, the locked state is released by the knock cam mechanism unit <NUM>, and the position of the electronic pen main unit <NUM> in the pen casing <NUM> returns to the state of <FIG> by a spring <NUM> for return. The detailed configuration of the knock cam mechanism unit <NUM> and operation thereof are well known, and therefore description thereof is omitted here.

<FIG> is a diagram illustrating an appearance configuration example of the electronic pen main unit <NUM> of this embodiment. Furthermore, <FIG> illustrates an electrical connection example at the joining part between the electronic pen main unit <NUM> of this embodiment and the fitting part 43a of the casing <NUM> of the electronic pen <NUM>. Furthermore, <FIG> is a diagram schematically illustrating the state in which the electronic circuit inside the electronic pen main unit <NUM> and electronic circuit components disposed on the pen casing <NUM> of the electronic pen <NUM> are electrically connected when the electronic pen main unit <NUM> is fitted to the fitting part 43a.

The electronic pen main unit <NUM> of the electronic pen <NUM> of the first embodiment is made to have a configuration that can establish compatibility with a replacement core of a ballpoint pen except the configuration of the rear end side fitted to the fitting part 43a of the pen casing <NUM>. <FIG> depicts diagrams illustrating a configuration example of the pen tip side of the electronic pen main unit <NUM> of this embodiment, <FIG> is a diagram illustrating the appearance thereof, and <FIG> is a longitudinal sectional view thereof. Furthermore, <FIG> depicts an exploded perspective view for explaining a configuration example of the pen tip side of the electronic pen main unit <NUM> of this embodiment, illustrated in <FIG>.

In the electronic pen main unit <NUM> of this embodiment, as illustrated in <FIG>, <FIG>, a peripheral electrode <NUM> composed of an electrically-conductive component, for example, an electrically-conductive metal, is joined to the pen tip side of the main body tubular part <NUM> with the interposition of a tubular joining component <NUM>, so that a casing <NUM> (hereinafter, referred to as a main unit casing <NUM>) of the electronic pen main unit <NUM> is configured.

In this example, as illustrated in <FIG>, the main body tubular part <NUM> is configured through joining of a resin pipe part 31b to the rear end side of the metal pipe part 31a on the side opposite to the pen tip side. Furthermore, in this example, for the main body tubular part <NUM>, the peripheral electrode <NUM> is joined to the pen tip side of the metal pipe part 31a with the interposition of the tubular joining component <NUM>. The tubular joining component <NUM> also plays a role in insulation between the metal pipe part 31a and the peripheral electrode <NUM>. Moreover, at the rear end part of the resin pipe part 31b, a rear-end-part connector fitted to the fitting part 43a disposed in the pen casing <NUM> of the electronic pen <NUM>, a connector plug <NUM> in this example, is disposed. Meanwhile, at the fitting part 43a of the pen casing <NUM>, a joining connector joined to the rear-end-part connector of the electronic pen main unit <NUM>, a connector jack <NUM> in this example, is disposed.

In a hollow part 30a of the main unit casing <NUM>, as illustrated by dotted lines in <FIG> and <FIG>, a core body holding component <NUM>, a writing pressure detecting unit <NUM>, a printed board <NUM> on which the signal transmitting circuit is mounted, and a rechargeable capacitor <NUM> as an example of the power storage element for supply voltage provision are disposed in such a manner as to be lined up in the axial center direction and be housed sequentially from the pen tip side.

This connector plug <NUM> includes multiple terminal parts, in this example, five terminal parts 51a, 52a, 53a, 54a, and 55a, that are electrically connected to the capacitor <NUM> housed in the electronic pen main unit <NUM> and the electronic circuit formed on the printed board <NUM> and are insulated from each other.

In the electronic pen main unit <NUM> of this embodiment, the five terminal parts 51a, 52a, 53a, 54a, and 55a of the connector plug <NUM> are configured as follows. Specifically, in this example, the terminal part 51a is composed of a conductor metal that configures a core bar at the center. Furthermore, in the example of <FIG>, the connector plug <NUM> is configured through combining of the terminal parts 52a, 53a, 54a, and 55a that each have an inner wall surface on which an insulating layer is formed and have a cylindrical shape with the bar-shaped conductor metal of this terminal part 51a in a concentric manner.

In this case, the terminal part 51a of the conductor metal that configures the core bar at the center is set as the tip part in the axial center direction and its annular circumferential surface and tip are made to be exposed for a predetermined length in the axial center direction. In addition, in each of the cylindrical terminal parts 52a, 53a, 54a, and 55a, its annular circumferential surface is made to be exposed for a predetermined length in the axial center direction. That is, the five terminal parts 51a, 52a, 53a, 54a, and 55a of the connector plug <NUM> are in the state in which circular annular conductor contact parts are exposed at different positions in the axial center direction. The terminal part 51a has a circular column shape and its annular circumferential side surface and tip part configure the conductor contact part.

When this connector plug <NUM> is inserted into a fitting recess of the connector jack <NUM> that configures the connector for joining formed at the fitting part 43a made on the rotor <NUM> disposed in the hollow part of the pen casing <NUM> of the electronic pen <NUM>, as illustrated in <FIG>, the connector plug <NUM> enters the state of being elastically connected to each of five contact terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> disposed in the connector jack <NUM>. Each of the five contact terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> is composed of an electrically-conductive elastic metal and is electrically connected to a respective one of the electrodes 2d and 2e for charging, the side switch <NUM>, and the conductor band 2f that are disposed on the pen casing <NUM> (see <FIG>).

Therefore, through the insertion and joining of the connector plug <NUM> into the connector jack <NUM>, electronic circuit components inside the electronic pen main unit <NUM> and electronic circuit components disposed on the pen casing <NUM> of the electronic pen <NUM> are electrically connected.

As illustrated in <FIG>, in this embodiment, the terminal parts 51a, 52a, 53a, 54a, and 55a of the connector plug <NUM> are each electrically connected to a respective one of the electrodes 2e and 2d for charging, both ends 2Sa and 2Sb of the side switch <NUM>, and the conductor band 2f through the five contact terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> disposed in the connector jack <NUM> (diagrammatic representation of the contact terminals of the connector jack <NUM> is omitted in <FIG>).

At this time, the circular annular conductor contact parts of the terminal parts 51a, 52a, 53a, 54a, and 55a of the connector plug <NUM> are connected to the contact terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, respectively, of the connector jack <NUM>. Therefore, even when the electronic pen main unit <NUM> rotates around the center line in the axial center direction, the electrical connection is always kept, and electrical non-contact can be avoided.

Due to the above configuration, when the electronic pen main unit <NUM> is fitted to the fitting part 43a of the rotor <NUM> of the knock cam mechanism unit <NUM> of the pen casing <NUM> of the electronic pen <NUM>, both ends of the capacitor <NUM> housed in the electronic pen main unit <NUM> are connected to the electrodes 2d and 2e for charging on the pen casing <NUM> of the electronic pen <NUM>. Due to this, when a supply voltage is not stored in the capacitor <NUM>, the capacitor <NUM> is charged through the electrodes 2d and 2e for charging, and a sufficient supply voltage is stored.

Furthermore, the electronic circuit of the electronic pen main unit <NUM> becomes capable of detecting the state of the side switch <NUM> and can transmit information regarding the detected state of the side switch <NUM> with the information included in a signal sent out by a core body <NUM>. Moreover, the earth electrode of the electronic pen main unit <NUM> and the conductor band 2f of the pen casing <NUM> are electrically connected. Therefore, through grasping of the part of the conductor band 2f by the user, the earth electrode of the electronic pen main unit <NUM> can be grounded through the human body, and transmission and reception of signals from the electronic pen main unit <NUM> can be stably carried out.

Next, a configuration example of the pen tip side of the electronic pen main unit <NUM> of this embodiment will be further described with reference to <FIG> and <FIG>.

In this example, as illustrated in <FIG> and <FIG>, the peripheral electrode <NUM> disposed on the pen tip side of the main body tubular part <NUM> is made into a shape having a cylindrical shape part 33a in which the outer diameter is constant and a tapered part 33b formed into a tapered shape in such a manner as to be gradually tapered toward the pen tip side. The metal pipe part 31a of the main body tubular part <NUM> has a cylindrical shape with an outer diameter equal to an outer diameter R2 (> R1) of the cylindrical shape part 33a of the peripheral electrode <NUM>. For example, R2 = <NUM> millimeters is set.

The tubular joining component <NUM> is composed of an insulating material, resin in this example, and is a tubular body like one illustrated in <FIG>. At a middle position on its outer circumferential surface in the axial center direction, a ring-shaped flange part 32F that protrudes from this outer circumferential side surface in the direction orthogonal to the axial center direction is formed. This ring-shaped flange part 32F has a predetermined width W (see <FIG>) in the axial center direction, and its end surface is flush with the main body tubular part <NUM> and the peripheral electrode <NUM> without having any step being generated and configures part of the main unit casing <NUM> as illustrated in <FIG>. That is, the diameter of the outer circumferential part of the ring-shaped flange part 32F is selected to be equal to the outer diameter of the peripheral electrode <NUM> and the metal pipe part 31a of the main body tubular part <NUM>.

Furthermore, the pen tip side, which is one side in the axial center direction, relative to the ring-shaped flange part 32F in this tubular joining component <NUM> is made into a first fitting tubular part 32a fitted to the cylindrical shape part 33a of the peripheral electrode <NUM>, and the configuration is made in such a manner that the cylindrical shape part 33a of the peripheral electrode <NUM> is joined to the first fitting tubular part 32a through being press-fitted thereto until reaching the place of the ring-shaped flange part 32F.

Moreover, the rear end side in the axial center direction relative to the ring-shaped flange part 32F in the tubular joining component <NUM> is made into a second fitting tubular part 32b fitted to the metal pipe part 31a of the main body tubular part <NUM>, and the configuration is made in such a manner that the metal pipe part 31a of the main body tubular part <NUM> is joined to the second fitting tubular part 32b through being press-fitted thereto until reaching the place of the ring-shaped flange part 32F.

In the state in which the metal pipe part 31a of the main body tubular part <NUM> and the peripheral electrode <NUM> are joined to the tubular joining component <NUM>, the main unit casing <NUM> of one tubular body is formed as illustrated in <FIG> and <FIG> and 1B. Furthermore, the metal pipe part 31a of the main body tubular part <NUM> composed of an electrically-conductive material and the peripheral electrode <NUM> are not in contact and are in a state of being electrically isolated (insulated) from each other due to the existence of the ring-shaped flange part 32F of the tubular joining component <NUM>.

As illustrated in <FIG>, the hollow part 30a exists inside the main unit casing <NUM>. Furthermore, a front cap <NUM> composed of an insulating material is mounted on the pen tip side of the peripheral electrode <NUM> of the main unit casing <NUM> as illustrated in <FIG> and <FIG>. The front cap <NUM> has, on its tip side, an opening 34a (see <FIG>) with a diameter larger than that of the center electrode <NUM> and the opening 34a communicates with the hollow part 30a of the main unit casing <NUM>.

The center electrode <NUM> is what configures a core body of the electronic pen main unit <NUM> of this embodiment and is composed of an electrically-conductive component, in this example, an electrically-conductive metal. Furthermore, as illustrated in <FIG>, this center electrode <NUM> is inserted into the main unit casing <NUM> from the opening 34a of the front cap <NUM>, and the end part on the side opposite to the pen tip side is mounted to the core body holding component <NUM> attachably and detachably.

The core body <NUM> and the peripheral electrode <NUM> that are composed of the electrically-conductive material are electrically isolated (insulated) by the front cap <NUM> that is the insulating material as illustrated in <FIG>. In the electronic pen main unit <NUM> of this embodiment, when the center electrode <NUM> is mounted, the peripheral electrode <NUM> is disposed to surround the rear end side relative to a tip part 35a that becomes the pen tip in the center electrode <NUM> as illustrated in <FIG>. In the following description, the center electrode <NUM> will be referred to as the core body <NUM>.

The tapered part 33b on the pen tip side in the peripheral electrode <NUM> of the main unit casing <NUM> has a diameter that gradually becomes smaller as the position gets closer to the pen tip side. In this embodiment, as illustrated in <FIG>, the pen tip side relative to a middle position in the axial center direction in the tapered part 33b is configured to be equal to or smaller than the diameter R0 of the opening 2b on the pen tip side in the pen casing <NUM>.

The electronic pen main unit <NUM> with the above configuration can be housed in the pen casing <NUM> by fitting its main body tubular part <NUM> to the fitting part 43a of the rotor <NUM> of the knock cam mechanism unit <NUM>. Furthermore, in the electronic pen <NUM> of this embodiment, the user presses down the end part 42a of the knock bar <NUM> when using the electronic pen <NUM> with a position detecting device. Thereupon, in the electronic pen <NUM>, the state is made in which, as illustrated in <FIG>, the tip part 35a of the core body <NUM>, the front cap <NUM>, and a part of the pen tip side of the tapered part 33b of the peripheral electrode <NUM> protrude to the external from the opening 2b of the pen casing <NUM>.

After the use of the electronic pen <NUM> ends, by pressing down the end part 42a of the knock bar <NUM> again, the state can be made in which the whole of the electronic pen main unit <NUM> is housed in the hollow part 2a of the pen casing <NUM> as illustrated in <FIG>. At this time, the whole of the electronic pen main unit <NUM> is housed in the hollow part 2a of the pen casing <NUM>, and the tip part 35a of the core body <NUM> of the electronic pen main unit <NUM> enters the state of being protected by the pen casing <NUM>.

Moreover, in this embodiment, as illustrated in <FIG>, a board holder <NUM> in which the printed board <NUM> is placed on a board placement pedestal <NUM> is housed in the hollow part 30a of the main unit casing <NUM>.

The board holder <NUM> is composed of an insulating resin and has a writing pressure detecting unit holding part <NUM> for housing and holding the writing pressure detecting unit <NUM> on the side opposite to the side of the board placement pedestal <NUM> in the longitudinal direction that is the axial center direction of the electronic pen main unit <NUM>. As illustrated in <FIG>, the board holder <NUM> is made to have a configuration in which the writing pressure detecting unit holding part <NUM> and the board placement pedestal <NUM> are continuous in the longitudinal direction that is the axial center direction of the electronic pen main unit <NUM> when the board holder <NUM> is housed in the hollow part of the main unit casing <NUM>. The writing pressure detecting unit holding part <NUM> is made into a cylindrical shape having a hollow part inside which multiple parts of the writing pressure detecting unit <NUM> are housed. The board placement pedestal <NUM> is made into a shape that is a boat shape on which the printed board <NUM> is placed to be held, and is like one obtained by cutting a tubular body by substantially half along the axial center direction.

The board holder <NUM> is housed in the main unit casing <NUM> in such a manner that the writing pressure detecting unit holding part <NUM> is set on the pen tip side. Furthermore, the configuration is made in such a manner that the core body holding component <NUM> that is fitted to the core body <NUM> and holds the core body <NUM> is joined to the writing pressure detecting unit <NUM> held by this writing pressure detecting unit holding part <NUM>, and the pressure (writing pressure) applied to the core body <NUM> is transmitted to the writing pressure detecting unit <NUM>.

The board holder <NUM> is subjected to position restriction in such a manner as not to move in the axial center direction in the main unit casing <NUM> through fitting and joining of the writing pressure detecting unit holding part <NUM> to the second fitting tubular part 32b of the tubular joining component <NUM> in the axial center direction as illustrated in <FIG>.

Furthermore, although diagrammatic representation is omitted, both ends of the capacitor <NUM> disposed on the side opposite to the writing pressure detecting unit holding part <NUM> and copper foil patterns of a power supply line and an earth line of the printed board <NUM>, on the board placement pedestal <NUM> of the board holder <NUM>, are electrically connected. Due to this, the voltage of the capacitor <NUM> is supplied to the circuit formed on the printed board <NUM> as a supply voltage.

In this embodiment, the metal pipe part 31a of the main body tubular part <NUM> composed of the electrically-conductive material is electrically connected to the copper foil pattern of the earth line of the printed board <NUM>.

In this embodiment, on the printed board <NUM>, disposed is a circuit part that is composed of the signal transmitting circuit that generates signals to be sent out from the core body <NUM> and the peripheral electrode <NUM>, an IC (Integrated Circuit) <NUM> (see <FIG>) that configures a control circuit that controls transmission of the signals from the signal transmitting circuit to the core body <NUM> and the peripheral electrode <NUM>, and peripheral circuit part thereof. A charging circuit of the capacitor <NUM> is included in the peripheral circuit part although diagrammatic representation is omitted. The charging circuit of the capacitor <NUM> may be disposed outside the electronic pen <NUM>.

As illustrated in <FIG> and an exploded perspective view of <FIG>, the core body holding component <NUM> that holds the core body <NUM> through fitting is composed of an electrically-conductive elastic component <NUM>, a core body holder <NUM>, a coil spring <NUM>, and a conductor terminal component <NUM>. The core body holding component <NUM> also plays a role as a transmitting component of the writing pressure applied to the core body <NUM> for the writing pressure detecting unit <NUM>.

In this embodiment, as illustrated in <FIG> and <FIG>, the core body <NUM> is fitted into the core body holder <NUM> composed of an electrically-conductive material through the electrically-conductive elastic component <NUM> and is thereby joined to the core body holder <NUM> to be held. The electrically-conductive elastic component <NUM> is composed of, for example, electrically-conductive rubber and is formed into a cylindrical shape having a through-hole 71a into which the end part of the core body <NUM> on the side opposite to the tip part 35a is fitted.

The core body holder <NUM> is composed of an electrically-conductive material, for example, SUS (Steel Special Use Stainless), and is an object in which a housing fitting part <NUM> having a recessed hole 721a in which the electrically-conductive elastic component <NUM> is housed and fitted and a bar-shaped part <NUM> fitted into a holding component <NUM> to be described later in the writing pressure detecting unit <NUM> are monolithically formed.

Furthermore, the configuration is made in such a manner that the pressure (writing pressure) applied to the core body <NUM> is transmitted to the writing pressure detecting unit <NUM> through fitting of a tip part 722a of the bar-shaped part <NUM> of the core body holder <NUM> into the holding component <NUM> of the writing pressure detecting unit <NUM> held by the writing pressure detecting unit holding part <NUM>. In this case, the configuration is made in such a manner that the core body holder <NUM> is always biased toward the side of the core body <NUM> against the board holder <NUM> by the coil spring <NUM> as an example of an elastic component composed of an electrically-conductive material such as an electrically-conductive metal.

The coil spring <NUM> configures, with the conductor terminal component <NUM>, a component for electrical connection for transmitting a signal from the IC <NUM> disposed on the printed board <NUM> to the core body <NUM>. In the electronic pen main unit <NUM> of this embodiment, a transmission signal generated by the signal transmitting circuit configured on the printed board <NUM> is supplied to the core body <NUM> through the component for electrical connection including this coil spring <NUM> and the conductor terminal component <NUM>.

Specifically, in this embodiment, on the writing pressure detecting unit holding part <NUM> of the board holder <NUM>, the conductor terminal component <NUM> composed of a material having electrical conductivity, for example, SUS, is mounted in such a manner as to cover the side of an opening 302a into which the bar-shaped part <NUM> of the core body holder <NUM> is inserted as illustrated in <FIG>.

As illustrated in <FIG>, this conductor terminal component <NUM> has an abutting plate part <NUM> that covers the side of the opening 302a of the writing pressure detecting unit holding part <NUM> of the board holder <NUM> and has a through-hole 741a in which the bar-shaped part <NUM> of the core body holder <NUM> is inserted.

Furthermore, an extending part <NUM> that extends to the part of the board placement pedestal <NUM> is disposed across the part of the writing pressure detecting unit holding part <NUM> of the board holder <NUM>. Moreover, in the state in which the conductor terminal component <NUM> is mounted on the writing pressure detecting unit holding part <NUM> of the board holder <NUM>, as illustrated in <FIG>, a terminal part 742a at the tip of the extending part <NUM> that extends from the conductor terminal component <NUM> abuts against a conductor on the back surface side of the printed board <NUM> placed on the board placement pedestal <NUM> of the board holder <NUM> and is soldered thereto, for example. Due to this, the conductor terminal component <NUM> and the signal transmitting circuit disposed on the printed board <NUM> are electrically connected.

The bar-shaped part <NUM> of the core body holder <NUM> into which the electrically-conductive elastic component <NUM> is fitted is inserted into the hollow part of the writing pressure detecting unit holding part <NUM> of the board holder <NUM> through the through-hole 741a of the abutting plate part <NUM> of the conductor terminal component <NUM> and is fitted into the writing pressure detecting unit holding part <NUM> in the state in which the coil spring <NUM> is interposed. The inner diameter of the coil spring <NUM> is set larger than the outer shape of the bar-shaped part <NUM> of the core body holder <NUM>.

The coil spring <NUM> elastically gets contact with the core body holder <NUM> and abuts against and elastically gets contact with the abutting plate part <NUM> of the conductor terminal component <NUM>. The coil spring <NUM> is composed of an electrically-conductive material, and the electrically-conductive elastic component <NUM> and the core body holder <NUM> have electrical conductivity. Thus, the signal transmitting circuit disposed on the printed board <NUM> and the electrically-conductive elastic component <NUM> fitted into the core body holder <NUM> are electrically connected through the conductor terminal component <NUM>. Therefore, fitting of the core body <NUM> into the electrically-conductive elastic component <NUM> makes the state in which a signal from the signal transmitting circuit disposed on the printed board <NUM> is supplied to the core body <NUM>.

Next, description will be made about the configuration of the writing pressure detecting unit holding part <NUM> of the board holder <NUM> and the writing pressure detecting unit <NUM> and fitting of the holding component <NUM> of the writing pressure detecting unit <NUM> and the core body holder <NUM>.

The writing pressure detecting unit <NUM> is housed in the writing pressure detecting unit holding part <NUM>, and the configuration is made as illustrated in <FIG>, thereby configuring a module for writing pressure detection. Furthermore, the core body <NUM> is joined to this module for writing pressure detection through the core body holder <NUM>. Due to this, the writing pressure applied to the tip part 35a of the core body <NUM> is detected by the writing pressure detecting unit <NUM> of the module for writing pressure detection. In this case, the module for writing pressure detection detects the writing pressure through movement of a portion of the parts of the writing pressure detecting unit <NUM> that configures the module in the axial center direction together with the core body <NUM> and the core body holder <NUM> according to the writing pressure applied to the tip part 35a of the core body <NUM>.

The writing pressure detecting unit <NUM> of this example is a case in which a capacitance-variable capacitor whose capacitance changes according to the writing pressure applied to the core body <NUM> is used, and is composed of multiple parts, a dielectric <NUM>, a terminal component <NUM>, the holding component <NUM>, an electrically-conductive component <NUM>, and an elastic component <NUM>, as illustrated in <FIG>.

In the state in which the core body holder <NUM> is fitted into the writing pressure detecting unit holding part <NUM> of the board holder <NUM> as above, the core body <NUM> is press-fitted into the through-hole 71a of the electrically-conductive elastic component <NUM> fitted into the core body holder <NUM>. Due to this, the core body <NUM> is firmly held with respect to the core body holder <NUM> by the electrically-conductive elastic component <NUM> as described above. The core body <NUM> can be pulled out in the direction toward the side of the tip part 35a from the state of being fitted into the core body holder <NUM> and being held and can be replaced as described above.

In this electronic pen main unit <NUM>, when a pressure is applied to the tip part 35a of the core body <NUM>, the core body <NUM> is displaced toward the rear end side in the axial center direction according to the pressure. Due to this displacement, the holding component <NUM> in the writing pressure detecting unit holding part <NUM> is displaced toward the side of the dielectric <NUM> against an elastic biasing force of the elastic component <NUM>. As a result, the electrically-conductive component <NUM> fitted into the holding component <NUM> is displaced toward the side of the dielectric <NUM>, so that the distance between the electrically-conductive component <NUM> and the dielectric <NUM> and the contact area between the electrically-conductive component <NUM> and the dielectric <NUM> change according to the pressure applied to the core body <NUM>.

Due to this, the capacitance of a capacitance-variable capacitor formed between the terminal component <NUM> that configures a first electrode and the electrically-conductive component <NUM> that configures a second electrode changes according to the pressure applied to the core body <NUM>. This change in the capacitance of the capacitance-variable capacitor is detected by the IC <NUM> disposed on the printed board <NUM>, and the writing pressure is detected.

The writing pressure detecting unit <NUM> is not limited to one with the above-described configuration. For example, one in which a capacitance-variable capacitor includes a semiconductor chip formed of a MEMS (Micro Electro Mechanical Systems) element (refer to patent document (<CIT>), for example) may be used.

Next, description will be made about the peripheral electrode <NUM> and an electrical connection with the circuit part of the printed board <NUM>. In the outer circumferential surface of the tubular joining component <NUM>, a recessed groove (diagrammatic representation is omitted) is formed from the first fitting tubular part 32a to the second fitting tubular part 32b by passing through the lower part of the ring-shaped flange part 32F in the direction along the axial center direction of the tubular joining component <NUM>.

Furthermore, a recessed groove (diagrammatic representation is omitted) continuous with the recessed groove of the second fitting tubular part 32b is formed also in the circumferential side surface of the writing pressure detecting unit holding part <NUM> of the board holder <NUM>. In this continuous recessed groove, as illustrated in <FIG>, a connection terminal conductor <NUM> composed of an electrically-conductive material, in this example, an electrically-conductive metal, is disposed. Furthermore, as illustrated in <FIG>, an end part 11a of the connection terminal conductor <NUM> disposed in the recessed groove on the side of the first fitting tubular part 32a of the tubular joining component <NUM> is disposed in such a manner that at least part of the end part 11a slightly bulges out relative to the outer circumferential surface of the first fitting tubular part 32a. However, the depth of the recessed groove of the part of the end part 11a is set to a depth that allows the end part 11a to be elastically pressed downward when the end part 11a is pressed down from above.

Due to this, the configuration is made in such a manner that the end part 11a of the connection terminal conductor <NUM> surely gets contact with the inner wall of the peripheral electrode <NUM> and the state in which the peripheral electrode <NUM> and the connection terminal conductor <NUM> are electrically connected is made when the peripheral electrode <NUM> is fitted to the first fitting tubular part 32a of the tubular joining component <NUM>. Furthermore, an end part 11b that extends to the side of the printed board <NUM> of the connection terminal conductor <NUM> is electrically connected to the side of a back surface 9b of the printed board <NUM> as illustrated in <FIG>. Although diagrammatic representation is omitted, the end part 11b of the connection terminal conductor <NUM> is electrically connected to the circuit part on the front surface side of the printed board <NUM> via a through-hole.

The depth of the recessed groove in which the connection terminal conductor <NUM> is disposed is set to a depth with which the connection terminal conductor <NUM> does not get contact with the metal pipe part 31a when the metal pipe part 31a of the main body tubular part <NUM> is fitted to the second fitting tubular part 32b. Alternatively, an insulator may be interposed between the connection terminal conductor <NUM> and the metal pipe part 31a.

Next, an electrical configuration example of the electronic pen main unit <NUM> of this embodiment is illustrated in <FIG>. In this example, as illustrated in <FIG>, a control circuit <NUM> includes the IC <NUM> disposed on the printed board <NUM>. Furthermore, to this control circuit <NUM>, a signal transmitting circuit <NUM> and a signal receiving circuit <NUM> are connected and a variable-capacitance capacitor 8C including the writing pressure detecting unit <NUM> is connected. A resistor 8R is connected in parallel to the variable-capacitance capacitor 8C.

Moreover, a signal output end of the signal transmitting circuit <NUM> is connected to the core body <NUM> through a switch circuit <NUM>. In this case, the interposition of the conductor terminal component <NUM>, the core body holder <NUM>, and the electrically-conductive elastic component <NUM> between the core body <NUM> and the switch circuit <NUM> is as described above.

Furthermore, in this example, the signal output end of the signal transmitting circuit <NUM> is connected to a terminal S of a changeover switch circuit <NUM>. A movable terminal M of this changeover switch circuit <NUM> is connected to the peripheral electrode <NUM>. In this case, the connection terminal conductor <NUM> is interposed between the peripheral electrode <NUM> and the changeover switch circuit <NUM>.

A terminal R of the changeover switch circuit <NUM> is connected to an input end of the signal receiving circuit <NUM>. Furthermore, a terminal G of the changeover switch circuit <NUM> is connected to an earth electrode (ground electrode).

Moreover, the control circuit <NUM> supplies the switch circuit <NUM> with a control signal SW1 that carries out on/off-control of the switch circuit <NUM>. Furthermore, the control circuit <NUM> supplies the changeover switch circuit <NUM> with a changeover control signal SW2 to switch which of the terminal S, the terminal R, and the terminal G the movable terminal M is to be connected to.

Although diagrammatic representation is omitted, the voltage of the capacitor <NUM> is supplied to each of the control circuit <NUM>, the signal transmitting circuit <NUM>, the signal receiving circuit <NUM>, the switch circuit <NUM>, and the changeover switch circuit <NUM> as a supply voltage.

The signal receiving circuit <NUM> receives a signal received by the peripheral electrode <NUM> through capacitive coupling (electric field coupling) with a position detecting sensor of a position detecting device and executes processing of demodulation and so forth according to the received signal to send a signal of the processing result to the control circuit <NUM>.

The control circuit <NUM> analyzes the signal from the signal receiving circuit <NUM> and determines the specifications of the position detecting device of the counterpart. In addition, the control circuit <NUM> settles the timing at which interaction of a signal is carried out with the position detecting sensor of the position detecting device of the counterpart. Furthermore, the control circuit <NUM> controls the format of a signal to be output from the signal transmitting circuit <NUM> in such a manner that the format becomes what matches the specifications of the position detecting device of the counterpart and carries out interaction with the position detecting sensor at the settled timing.

Basically, the signal transmitting circuit <NUM> outputs, under control of the control circuit <NUM>, a signal including a signal for position detection (burst signal) with a predetermined frequency for position detection in the position detecting device and writing pressure information according to the writing pressure detected by the writing pressure detecting unit <NUM>. Furthermore, the signal transmitting circuit <NUM> outputs also a signal for detection of a tilt angle of the electronic pen <NUM>. That is, the signal transmitting circuit <NUM> sends out the burst signal for position detection and the burst signal for detection of the tilt angle of the electronic pen <NUM> under control by the control circuit <NUM>.

Moreover, in the period in which the burst signal for position detection is being sent out from the signal transmitting circuit <NUM>, the control circuit <NUM> carries out operation of detecting the writing pressure on the basis of the capacitance of the variable-capacitance capacitor 8C including the writing pressure detecting unit <NUM>.

In this example, the control circuit <NUM> first charges the variable-capacitance capacitor 8C to the fully-charged state and thereafter stops the charging to thereby set the variable-capacitance capacitor 8C to the state of being discharged through the resistor 8R. Then, the control circuit <NUM> measures the time from the discharging start timing to the timing when the voltage across the variable-capacitance capacitor 8C becomes a predetermined voltage set in advance and detects the capacitance of the variable-capacitance capacitor 8C at the time from the time. The capacitance of the variable-capacitance capacitor 8C corresponds to the writing pressure applied to the core body <NUM> at the time and detects the writing pressure on the basis of the detected capacitance.

The control circuit <NUM> converts the detected writing pressure to a digital signal of multiple bits in this example and controls the signal transmitting circuit <NUM> to output writing pressure information according to this digital signal from this signal transmitting circuit <NUM>.

Furthermore, a supply voltage Vcc stored in the capacitor <NUM> is supplied to each of the control circuit <NUM>, the signal transmitting circuit <NUM>, the signal receiving circuit <NUM>, the switch circuit <NUM>, and the changeover switch circuit <NUM>. In this embodiment, a charging circuit <NUM> of the capacitor <NUM> is disposed on the printed board <NUM> and is connected to the terminals 52a and 51a of the connector plug <NUM> to which the electrodes 2d and 2e for charging are connected. Therefore, although diagrammatic representation is omitted, when the electrodes 2d and 2e for charging are connected to an AC power supply through an adapter for charging, the capacitor <NUM> is charged by the charging circuit <NUM>.

Moreover, the side switch <NUM> disposed on the pen casing <NUM> is connected to the control circuit <NUM> through the terminals 53a and 54a of the connector plug <NUM>. The control circuit <NUM> determines the on- and off-states of the side switch <NUM> and generates information regarding the determined state of the side switch <NUM> to transmit the generated information regarding the state of the side switch <NUM> to the position detecting device through the signal transmitting circuit <NUM>.

The earth electrode (ground conductor) of the electronic pen main unit <NUM> is connected to the conductor band 2f through the terminal 55a of the connector plug <NUM>.

Next, a circuit configuration example of the position detecting device and the position detecting sensor will be described. <FIG> is a block diagram for explaining a configuration example of a reception processing circuit of a signal from the electronic pen <NUM> in a position detecting device <NUM> of a capacitive system.

As illustrated in <FIG>, the position detecting device <NUM> of this example is composed of a position detecting sensor <NUM> and a pen detecting circuit <NUM> connected to this position detecting sensor <NUM>. In this example, the position detecting sensor <NUM> is composed of a first conductor group in which multiple first conductors 211Y<NUM>, 211Y<NUM>, ···, 211Ym (m is an integer equal to or larger than <NUM>) that extend along the horizontal direction (X-axis direction) are disposed in a Y-axis direction in parallel separately from each other by a predetermined interval and a second conductor group in which multiple second conductors 212X<NUM>, 212X<NUM>, ···, 212Xn (n is an integer equal to or larger than <NUM>) that extend along the vertical direction (Y-axis direction) are disposed in the X-axis direction in parallel separately from each other by a predetermined interval.

In the following description, when there is no need to distinguish the multiple first conductors of the first conductor group and the multiple second conductors of the second conductor group from one another, the conductors will be referred to as the first conductor 211Y and the second conductor 212X.

The pen detecting circuit <NUM> is composed of a selection circuit <NUM> used as an input-output interface with the position detecting sensor <NUM>, an amplification circuit <NUM>, a band-pass filter <NUM>, a detection circuit <NUM>, a sample-hold circuit <NUM>, an AD (Analog to Digital) conversion circuit <NUM>, and a control circuit <NUM>.

The selection circuit <NUM> selects one conductor 211Y or 212X from the first conductor group and the second conductor group on the basis of a control signal from the control circuit <NUM>. The conductor selected by the selection circuit <NUM> is connected to the amplification circuit <NUM>, and a signal from the electronic pen <NUM> (electronic pen main unit <NUM> thereof) is detected by the selected conductor and is amplified by the amplification circuit <NUM>. The output of this amplification circuit <NUM> is supplied to the band-pass filter <NUM>, and only the component of the frequency of the signal transmitted from the electronic pen <NUM> is extracted.

An output signal of the band-pass filter <NUM> is detected by the detection circuit <NUM> and an output signal thereof is supplied to the sample-hold circuit <NUM> and is sampled and held by a sampling signal from the control circuit <NUM>. Thereafter, the signal is converted to a digital value by the AD conversion circuit <NUM>. Digital data from the AD conversion circuit <NUM> is read by the control circuit <NUM> and is processed.

The control circuit <NUM> sends out a control signal to each of the sample-hold circuit <NUM>, the AD conversion circuit <NUM>, and the selection circuit <NUM>. In addition, the control circuit <NUM> calculates position coordinates on the position detecting sensor <NUM> indicated by the electronic pen <NUM> from the digital data from the AD conversion circuit <NUM> and detects writing pressure information.

Furthermore, the control circuit <NUM> detects a tilt angle of the electronic pen <NUM> in a manner described below. A method of the detection of the tilt angle of the electronic pen <NUM> in this position detecting device <NUM> will be described with reference to <FIG>.

When the core body <NUM> of the electronic pen main unit <NUM> of the electronic pen <NUM> is in the perpendicular state with respect to the input surface of the position detecting sensor <NUM> as illustrated in a schematic diagram of <FIG>, in a position detection period Ta, capacitive coupling is made between the tip part 35a of the core body <NUM> and the position detecting sensor <NUM> and a region OBa in which the capacitive coupling is made is a region of a true circle as illustrated in <FIG>. On the other hand, in a tilt detection period Tb, capacitive coupling is made between the peripheral electrode <NUM> and the position detecting sensor <NUM> and a region OBa in which the capacitive coupling is made is a ring-shaped region as illustrated in <FIG>.

Furthermore, when the core body <NUM> of the electronic pen main unit <NUM> of the electronic pen <NUM> is in a tilt state with respect to the input surface of the position detecting sensor <NUM> as illustrated in a schematic diagram of <FIG>, the region OBa in which capacitive coupling is made between the tip part 35a of the core body <NUM> and the position detecting sensor <NUM> in the position detection period Ta substantially remains the region of the true circle as illustrated in <FIG>. On the other hand, the region OBb in which capacitive coupling is made between the peripheral electrode <NUM> and the position detecting sensor <NUM> in the tilt detection period Tb becomes a region of an elliptical shape that is according to the tilt angle and extends long in the direction of the tilt as illustrated in <FIG>.

Therefore, in the control circuit <NUM> of the position detecting device <NUM>, the magnitude of the tilt angle of the electronic pen <NUM> can be detected from the length in the major axis direction regarding the elliptical shape of the region OBb illustrated in <FIG>. Furthermore, the direction of the tilt of the electronic pen <NUM> can be detected by detecting the major axis direction of the elliptical shape of the region OBb with the indicated position of the electronic pen <NUM> illustrated in <FIG> being deemed as the point of origin.

In the above-described example, a signal with the same frequency as the signal supplied to the core body <NUM> is used for the peripheral electrode <NUM> used for detecting the tilt angle. However, the frequency of the signal supplied to the core body <NUM> and the frequency of the signal supplied to the peripheral electrode <NUM> may be made different. In this case, the signal from the core body <NUM> and the signal from the peripheral electrode <NUM> can be distinguished in the position detecting device <NUM>. Thus, in the electronic pen main unit <NUM> of the electronic pen <NUM>, the configuration may be made in such a manner that the signal from the core body <NUM> and the signal from the peripheral electrode <NUM> are simultaneously sent out to the position detecting sensor <NUM> instead of carrying out the position detection period Ta and the tilt detection period Tb in a time-sharing manner as described above.

According to the electronic pen main unit <NUM> of the above-described first embodiment, when the rear end part of the electronic pen main unit <NUM> is fitted to the fitting part 43a of the pen casing <NUM>, the connector plug <NUM> of the electronic pen main unit <NUM> and the connector jack <NUM> of the fitting part 43a are joined. Due to this, the electronic circuit inside the electronic pen main unit <NUM> connected to the connector plug <NUM> of the electronic pen main unit <NUM> and electronic circuit components such as the electrodes 2d and 2e for charging, the side switch <NUM>, and the conductor band 2f on the pen casing <NUM> connected to the connector jack <NUM> of the pen casing <NUM> are electrically connected.

Furthermore, the connector jack <NUM> is disposed at the fitting part 43a moved by the knock cam mechanism unit <NUM> as the movement mechanism disposed in the pen casing <NUM>, and the connector plug <NUM> is disposed at the rear end part of the electronic pen main unit <NUM> fitted to this fitting part. Therefore, the electrical connection is always secured even when the electronic pen main unit <NUM> moves in the axial center direction in the pen casing <NUM>.

Moreover, in the above-described embodiment, the circular annular conductor contact parts of the terminal parts 51a, 52a, 53a, 54a, and 55a of the connector plug <NUM> are connected to the contact terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, respectively, of the connector jack <NUM>. Therefore, even when the electronic pen main unit <NUM> rotates around the center line in the axial center direction, the electrical connection is always kept, and electrical non-contact can be avoided.

Furthermore, in the electronic pen <NUM> of this first embodiment, in use of the electronic pen <NUM> in which the pen tip side of the electronic pen main unit <NUM> protrudes to the external from the opening 2b of the pen casing <NUM> of the electronic pen <NUM>, not only the tip part 35a of the core body <NUM> but also part of the tapered part 33b on the pen tip side in the peripheral electrode <NUM> protrudes from the opening 2b of the pen casing <NUM>.

Therefore, according to the electronic pen <NUM> of this first embodiment, the distance between not only the tip part 35a of the core body <NUM> and the input surface of the position detecting sensor <NUM> but also the tapered part 33b on the pen tip side in the peripheral electrode <NUM> becomes short, and capacitive coupling (electric field coupling) between both the two becomes strong. Moreover, in this embodiment, because the pen tip side of the peripheral electrode <NUM> is made into the tapered part 33b, the cross-sectional area of the tip part thereof on the pen tip side is small, and the electric field coupling is made more strongly with the position detecting sensor <NUM>.

Therefore, the electronic pen <NUM> of this first embodiment can strongly make electric field coupling with the position detecting sensor <NUM> even when being made thinner. In the position detecting device <NUM>, it becomes possible to detect sensing of the position indicated by the electronic pen <NUM> with high sensitivity. In addition, in the electronic pen main unit <NUM> of the electronic pen <NUM> of this first embodiment, a signal from the position detecting device <NUM> is received by the peripheral electrode <NUM>, and the electronic pen main unit <NUM> starts transmission of a signal at a timing ordered by the received signal. This allows the position detecting device to wait for reception of the signal from the electronic pen main unit <NUM> while predicting transmission of the signal from the electronic pen main unit <NUM> of the electronic pen <NUM>, and favorable operation can be implemented even with the electric field coupling with smaller coupling strength compared with the electromagnetic induction system.

The connector plug <NUM> as an example of the rear-end-part connector of the electronic pen main unit <NUM> and the connector jack <NUM> as an example of the connector for joining at the fitting part 43a of the pen casing <NUM> are one example of the rear-end-part connector of the electronic pen main unit and the connector for joining at the fitting part of the pen casing, and the fitting configuration is not limited thereto.

<FIG> illustrates another example of the rear-end-part connector of the electronic pen main unit and the connector for joining at the fitting part of the pen casing. In an electronic pen main unit 3B of this example, only the configuration of the rear-end-part connector is different from the example of <FIG>, and the others are similar to the electronic pen main unit <NUM> of the above-described first embodiment. Thus, in the following description, in the electronic pen main unit 3B, a constituent part similar to that of the electronic pen main unit <NUM> is given the same reference numeral, and detailed description thereof is omitted.

In the electronic pen main unit 3B of this example, a connector plug 50B as an example of the rear-end-part connector is disposed at the rear end part of the resin pipe part 31b of the main body tubular part <NUM>. This connector plug 50B is what has a configuration similar to that of a pin plug for audio (for example, <NUM>-pole pin plug with a noise cancelling function). In this example, five terminal parts 51b, 52b, 53b, 54b, and 55b are in the state in which circular annular conductor contact parts with the same diameter are exposed at positions different in the axial center direction.

Specifically, the terminal part 51b at the tip of the five terminal parts 51b, 52b, 53b, 54b, and 55b is made into a tip terminal. The middle three terminal parts 52b, 53b, and 54b are each made into a ring terminal insulated from other terminal parts by insulating rings 56a, 56b, 56c, and 56d. The terminal part 55b on the root side of the electronic pen main unit 3B is made into a sleeve terminal.

A connector jack as an example of the connector for joining that is joined to the connector plug 50B of the electronic pen main unit 3B of this example and is disposed at the fitting part 43a of the pen casing <NUM> includes five contact terminals that get contact with each of the circular annular conductor contact parts of the five terminal parts 51b, 52b, 53b, 54b, and 55b and form an electrical connection similarly to <FIG> although diagrammatic representation is omitted here. Also in this example, the terminal parts 51b, 52b, 53b, 54b, and 55b of the connector plug 50B are each electrically connected to a respective one of the electrodes 2e and 2d for charging, both ends 2Sa and 2Sb of the side switch <NUM>, and the conductor band 2f on the pen casing <NUM> through the five contact terminals disposed in the connector jack.

Also in this example, the circular annular conductor contact parts of the terminal parts 51b, 52b, 53b, 54b, and 55b of the connector plug 50B are connected to a respective one of the five contact terminals of the connector jack of the fitting part 43a. Therefore, even when the electronic pen main unit 3B rotates around the center line in the axial center direction, the electrical connection is always kept, and electrical non-contact can be avoided.

In the above-described example, the rear-end-part connector of the rear end part on the side opposite to the pen tip side in the main body tubular part <NUM> of the electronic pen main unit <NUM> or the electronic pen main unit 3B is made to have a configuration of a connector plug, and the connector for joining at the fitting part 43a of the pen casing <NUM> is made to have a configuration of a connector jack. However, conversely, the rear-end-part connector of the electronic pen main unit <NUM> or the electronic pen main unit 3B may be made to have a configuration of a connector jack, and the connector for joining at the fitting part 43a of the pen casing <NUM> may be made to have a configuration of a connector plug.

An electronic pen of this second embodiment is a modification example of the first embodiment. In the above-described first embodiment, only one electronic pen main unit <NUM> or electronic pen main unit 3B is housed in the pen casing <NUM> of the electronic pen <NUM>. In this second embodiment, multiple electronic pen main units are housed in a pen casing of an electronic pen. Furthermore, by a knock mechanism as an example of the movement mechanism, one of the multiple electronic pen main units is selected, and the tip of the pen tip part of the selected electronic pen main unit is protruded from an opening of the casing on the pen tip side and is used.

The electronic pen main unit <NUM> or the electronic pen main unit 3B of the electronic pen <NUM> of the first embodiment is made to have a configuration that can establish compatibility with a replacement core of a ballpoint pen except the configuration of the rear end side fitted to the fitting part 43a of the pen casing <NUM>. As a commercially-available ballpoint pen, a multi-color ballpoint pen in which replacement cores different in the ink color are mounted exists. This second embodiment provides an electronic pen including housing the electronic pen main unit <NUM> in a casing with a configuration similar to that of the casing of this multi-color ballpoint pen.

<FIG> is a configuration diagram illustrating the appearance of an electronic pen <NUM> of this second embodiment. Also in this example of <FIG>, a pen casing <NUM> of the electronic pen <NUM> is composed of a transparent synthetic resin and is illustrated to be in the state in which the inside thereof is visible in a see-through manner.

The pen casing <NUM> of the electronic pen <NUM> has almost the same configuration as a casing and a knock mechanism of a commercially-available knock-type multi-color ballpoint pen. However, similarly to the pen casing <NUM> and the knock cam mechanism unit <NUM> of the electronic pen <NUM> of the first embodiment, a configuration in which electrodes 2Md and 2Me for charging, a side switch <NUM>, and a conductor band 2Mf are disposed on the pen casing <NUM> and a configuration of a fitting part to which an electronic pen main unit 3AES is fitted in the knock mechanism are different from the casing and the knock mechanism of the commercially-available knock-type multi-color ballpoint pen.

In this example of <FIG>, in the pen casing <NUM>, one electronic pen main unit 3AES is housed and replacement cores of ballpoint pens of two colors, for example, a replacement core 6R of a red ballpoint pen and a replacement core 6B of a black ballpoint pen, are housed. The electronic pen main unit 3AES is configured similarly to the electronic pen main unit <NUM> or the electronic pen main unit 3B of the first embodiment except that the electronic pen main unit 3AES is configured with the same dimensions as the replacement core of the multi-color ballpoint pen, and includes a rear-end-part connector with a configuration similar to that of the connector plug <NUM> or 50B, for example, on the rear end side of the main body tubular part <NUM>.

Furthermore, the knock mechanism of the electronic pen <NUM> is equipped with knock bars 42AES, 42R, and 42B to which the electronic pen main unit 3AES and the replacement cores 6R and 6B of the red and black ballpoint pens, respectively, are fitted. A fitting part 43AES disposed on the knock bar 42AES is made to have a configuration including a joining connector joined to the rear-end-part connector configured at the rear end part of the electronic pen main unit 3AES similarly to the fitting part 43a of the knock cam mechanism unit <NUM> in the first embodiment. Therefore, the electrodes 2Md and 2Me for charging, the side switch <NUM>, and the conductor band 2Mf are electrically connected to five terminals of the connector for joining.

The fitting parts 43R and 43B of the knock bars 42R and 42B are made into fitting parts of a multi-color ballpoint pen.

Any of the knock bars 42AES, 42R, and 42B is moved by sliding toward the pen tip side, and thereby the pen tip side of the electronic pen main unit 3AES or either the replacement core 6R or 6B of the red or black ballpoint pen protrudes from an opening 2Ma of the pen casing <NUM>. Furthermore, by the slide movement of the knock bar 42AES toward the pen tip side, the tip part 35a of the core body <NUM> and a part of the peripheral electrode <NUM> of the electronic pen main unit 3AES protrude to be caused to make electric field coupling with a position detecting sensor of a position detecting device.

In a case of the electronic pen <NUM> of the second embodiment, the electronic pen main unit 3AES and the replacement cores 6R and 6B of ballpoint pens are housed in the pen casing <NUM>, and therefore the axial center direction of the electronic pen main unit 3AES deviates from the opening 2Ma of the pen casing <NUM>. Thus, when the pen tip part of the electronic pen main unit 3AES is let out and protruded from the opening 2Ma of the pen casing <NUM> by using the knock mechanism, the electronic pen main unit 3AES pushed out slightly bends with respect to the fitting part 43AES of the pen casing <NUM>.

However, the main body tubular part <NUM> of the electronic pen main unit 3AES of this embodiment includes the resin pipe part 31b. Therefore, due to the elasticity of this resin pipe part 31b, it is possible to deal with the bending of the electronic pen main unit <NUM> at the time of letting-out of the tip part of the electronic pen main unit <NUM>. In a case of dealing with a mechanism of the casing of a multi-color ballpoint pen like this second embodiment, it is preferable that the length of the resin pipe part 31b in the axial center direction be adjusted to a length with which the bending at the time of letting-out of the tip part of the electronic pen main unit 3AES can be favorably absorbed by the resin pipe part 31b.

In the above-described second embodiment, only the fitting part 43AES of the knock bar 42AES in the three knock bars 42AES, 42R, and 42B is made to have a configuration including a conductor to which the electronic pen main unit <NUM> or the electronic pen main unit 3B can be fitted. However, two or all of the fitting parts of the three knock bars 42AES, 42R, and 42B may be made into ones for the electronic pen main unit <NUM> or the electronic pen main unit 3B, and the fitting parts may be made into ones with a configuration including a conductor. However, in the electronic pen main unit <NUM> or the electronic pen main unit 3B in this case, it is preferable that an IC and a peripheral circuit thereof for implementing a function of transmitting its own identification information to a position detecting device be disposed in the main unit casing <NUM> in which electronic circuit components are disposed.

In this case, the position detecting device used with the electronic pen main unit <NUM> or the electronic pen main unit 3B has a function of receiving and determining the identification information transmitted from each of the electronic pen main units <NUM> or the electronic pen main units 3B. Furthermore, the position detecting device determines the difference among the electronic pen main units 3AES fitted to the fitting parts 43AES, 43R, and 43B and implements functions assigned to the respective ones. For example, in a case in which all of the fitting parts of the three knock bars 42AES, 42R, and 42B are made into ones for the electronic pen main unit <NUM> or the electronic pen main unit 3B, to the electronic pen main unit fitted to the fitting part 43R, a function of representing a writing locus (character or figure) displayed according to the indicated position thereof by red can be assigned. Furthermore, to the electronic pen main unit fitted to the fitting part 43B, a function of representing a writing locus displayed according to the indicated position thereof by black can be assigned. Moreover, to the electronic pen main unit fitted to the fitting part 43AES, a function of erasing a writing locus input through indication previously according to the indicated position thereof can be assigned.

The functions assigned to the electronic pen main units are not only the display color of the locus according to the indicated position as in this example and may be the kinds of displayed line, such as the thickness of a locus, a solid line, a dotted line, and a one-dot chain line.

When multiple electronic pen main units <NUM> or 3B are housed in the pen casing <NUM>, the electrodes 2Ed and 2Ee for charging and the conductor band 2Mf can be made common to these multiple electronic pen main units <NUM> or 3B. Furthermore, the side switch <NUM> may be made common to the multiple electronic pen main units <NUM> or 3B housed in the pen casing <NUM>, or multiple side switches may be disposed on the pen casing <NUM> corresponding to a respective one of the multiple electronic pen main units <NUM> or 3B housed in the pen casing <NUM>.

Furthermore, although the second embodiment is the example including the three knock bars, the number of knock bars may be two or may be four or more.

In <FIG>, other embodiments of the electronic pen main unit are illustrated. <FIG> illustrates a modification example of another example of the electronic pen main unit 3B illustrated in <FIG> in the above-described first embodiment. This example is an example configured in consideration of common use with a replacement core of a ballpoint pen similarly to the second embodiment. In description of an electronic pen main unit 3C of this embodiment, a constituent part similar to that of the above-described electronic pen main unit 3B is given the same reference numeral, and detailed description thereof is omitted.

In the electronic pen main unit 3C of this embodiment, a peripheral electrode 33C with a different shape from the peripheral electrode <NUM> of the electronic pen main unit 3B of the first embodiment is used. Specifically, as illustrated in <FIG>, the peripheral electrode 33C of the electronic pen main unit 3C of this embodiment is made into a tubular shape whose outer diameter is constant in the axial center direction, and the outer diameter is set to a diameter R1 smaller than the diameter of the opening 2b (see <FIG>) of the pen casing <NUM> of the electronic pen.

Thus, in the electronic pen main unit 3C of this embodiment, because the configuration of the peripheral electrode 33C is different from that of the electronic pen main unit <NUM> in the first embodiment, a tubular joining component 32C that joins the peripheral electrode 33C to the main body tubular part <NUM> is configured in conformity to the configuration of the peripheral electrode 33C in such a manner that the peripheral electrode 33C can be joined to the main body tubular part <NUM> with the interposition of a ring-shaped flange part 32CF. Furthermore, a front cap 34C is also configured with change in conformity to the configuration of the peripheral electrode 33C. The others are made to have a configuration similar to that of the electronic pen main unit <NUM> of the first embodiment.

On the rear end side of the electronic pen main unit 3C in this example of <FIG>, the connector plug 50B as an example of the rear-end-part connector is disposed in this example similarly to the electronic pen main unit 3B. Furthermore, the electronic pen main unit 3C is fitted to the fitting part 43a of the pen casing <NUM> of the electronic pen <NUM> and the connector plug 50B as an example of the rear-end-part connector is electrically connected to a connector jack as an example of the connector for joining at the fitting part 43a.

Therefore, also in the electronic pen using the electronic pen main unit 3C of this example of <FIG>, the same operation and effects as the electronic pen <NUM> of the first embodiment can be obtained. At the time of use, the core body <NUM>, the front cap 34C, and a part of the peripheral electrode 33C on the pen tip side protrude to the external from an opening of a casing 2C of the electronic pen illustrated by dotted lines in <FIG>. In this case, the cylindrical part with the constant outer diameter in the peripheral electrode 33C is located at the part of opening of the casing 2C. Therefore, by adjusting the outer diameter of the cylindrical part of this peripheral electrode 33C, the pen tip side of the electronic pen main unit 3C can be easily kept from involving a backlash in the opening of the casing 2C.

Next, an example of <FIG> also illustrates a modification example of another example of the electronic pen main unit 3B illustrated in <FIG> in the above-described first embodiment. Parts of a main body tubular part 31D and a tubular joining component 32D of an electronic pen main unit 3D of this embodiment are different from the above-described electronic pen main unit 3B, and the other part is made into a similar configuration. Thus, also in the electronic pen main unit 3D of this embodiment, a constituent part similar to that of the electronic pen main unit 3B is given the same reference numeral and detailed description thereof is omitted.

The main body tubular part 31D of the electronic pen main unit 3D of this embodiment has an outer diameter R3 larger than the outer diameter R2 of the main body tubular part <NUM> of the above-described electronic pen main unit 3B. Furthermore, the inner diameter of the main body tubular part 31D of the electronic pen main unit 3D of this embodiment is set to a diameter larger than the inner diameter of the main body tubular part <NUM> of the electronic pen main unit <NUM> of the first embodiment.

Thus, in the electronic pen main unit 3D of this embodiment, because the configuration of the main body tubular part 31D is different from that of the electronic pen main unit 3B, the tubular joining component 32D that joins the peripheral electrode <NUM> to the main body tubular part 31D is configured in conformity to the configuration of the main body tubular part 31D in such a manner that the peripheral electrode <NUM> can be joined to the main body tubular part 31D with the interposition of a ring-shaped flange part 32DF.

The main body tubular part 31D of the electronic pen main unit 3D of this embodiment includes a hollow part with a large space. Furthermore, in the electronic pen main unit 3D of this embodiment, by use of the space of the large hollow part of this main body tubular part 31D, the configuration is made in such a manner that a primary cell (battery) 10BT is housed in the hollow part as illustrated in <FIG> instead of the capacitor <NUM> as the power storage element used in the above-described electronic pen main unit 3B. The other electronic circuit components in the main body tubular part 31D are housed in the main body tubular part 31D similarly to the first embodiment, and the necessary supply voltage to the respective parts is supplied from the primary cell 10BT incorporated in the main body tubular part 31D. Therefore, the electrodes 2d and 2e for charging do not need to be disposed on the pen casing 2D of the electronic pen <NUM> using the electronic pen main unit 3D of this embodiment.

In this example, the main body tubular part 31D of the electronic pen main unit 3D of this embodiment is formed of a metal pipe. In addition, on the rear end part thereof on the side opposite to the pen tip side, a component 31DE in which a connector plug 50B' as an example of the rear-end-part connector is formed on a resin base 31Da is mounted attachably and detachably. In the electronic pen main unit 3D of this embodiment, the configuration is made in such a manner that the primary cell 10BT housed in the main body tubular part 31D can be replaced through removal of the component 31DE.

The casing of the electronic pen that houses the electronic pen main unit 3D of this embodiment is set to a diameter larger than that of the casing <NUM> of the electronic pen of the above-described first embodiment. The other configuration of the casing of the electronic pen is made similar to the above-described embodiment and includes a movement mechanism such as a knock cam mechanism or knock mechanism. At a fitting part moved by the movement mechanism, a connector jack to which the connector plug 50B' of the rear end part of the electronic pen main unit 3D is joined and that is electrically connected to a side switch and the conductor band 2f is disposed.

Also in a case in which the main body tubular part 31D is configured into a thick shape as in the electronic pen main unit 3D of this embodiment, a secondary cell or a power storage element such as a capacitor may be disposed instead of disposing the primary cell 10BT in the hollow part of the main body tubular part 31D. In this case, the configuration of the rear-end-part connector of the main body tubular part 31D of the electronic pen main unit 3D is configured similarly to the electronic pen main unit or the electronic pen main unit 3B of the first embodiment, and the electrodes 2d and 2e for charging are disposed on the casing <NUM> of the electronic pen.

Also in the electronic pen using the electronic pen main unit 3D of this example of <FIG>, the operation and effects similar to the electronic pen <NUM> of the first embodiment can be obtained. At the time of use, the core body <NUM>, the front cap <NUM>, and a part of the tapered part of the peripheral electrode <NUM> on the pen tip side protrude to the external from an opening of a casing 2D of the electronic pen illustrated by dotted lines in <FIG>.

<FIG> is a modification example of the electronic pen main unit 3C of <FIG>. A peripheral electrode 33C' of an electronic pen main unit 3C' of this example of <FIG> is different from the peripheral electrode 33C of the electronic pen main unit <NUM> of the example of <FIG> in that the pen tip side is made into a tapered part 33C'b. Specifically, the peripheral electrode 33C' of the electronic pen main unit 3C' of this example is made into a shape in which the tapered part 33C'b is formed on the pen tip side of a cylindrical shape part 33C'a whose outer diameter is set to the diameter R1 smaller than the diameter R0 of the opening 2b (see <FIG>) of the pen casing <NUM> of the electronic pen. In this example, a front cap 34C' is disposed on the tip part of the tapered part 33C'b of the peripheral electrode 33C'. The others are configured similarly to the electronic pen main unit 3C of the example of <FIG>.

Also in a case of the electronic pen main unit 3C' of this example of <FIG>, at the time of use, the core body <NUM>, the front cap 34C', and a part of the peripheral electrode 33C' on the pen tip side protrude to the external from the opening of the casing 2C of the electronic pen. In this case, the part of the peripheral electrode 33C' that protrudes to the external includes not only the tapered part 33C'b but also a part of the cylindrical shape part 33C'a, and the part located at the opening of the casing 2C is the cylindrical shape part 33C'a. Therefore, the operation and effects similar to the example of <FIG> are provided.

Several of other configuration examples of the electronic pen including fitting the rear-end-part connector included in the electronic pen main unit to the fitting part that is movable in the casing by the movement mechanism and includes the connector for joining as described above will be described with reference to schematic configuration examples illustrated in <FIG>.

An electronic pen main unit 3E housed in an electronic pen 1E illustrated in <FIG> is different from the electronic pen main units of the above-described embodiments in that a supply voltage is obtained from a secondary cell (rechargeable battery) 12BT disposed in a casing 2E, and the others are made into a similar configuration.

In the electronic pen casing 2E of this example, a connector 90E for joining is disposed at a fitting part 43E moved by a knock bar 42E. In this connector 90E for joining, a terminal for supplying the supply voltage from the secondary cell 12BT to an electronic circuit inside the electronic pen main unit 3E and, in this example, a terminal to which a side switch 2ES is connected, are disposed. The conductor band 2f may be disposed on the pen casing 2E, and a terminal for connecting the conductor band 2f and an earth electrode of the electronic pen main unit 3E may be disposed.

When a rear-end-part connector 50E of the electronic pen main unit 3E is fitted to the fitting part 43E as illustrated in <FIG>, the rear-end-part connector 50E is joined to the connector 90E for joining disposed at the fitting part 43E, and the supply voltage from the secondary cell 12BT is supplied to the electronic circuit of the electronic pen main unit 3E. In addition, the side switch 2ES is connected to the electronic circuit, and the state thereof is allowed to be detected.

In this example, the secondary cell 12BT is configured to be charged from the external through electrodes 2Ed and 2Ee for charging.

According to this example, a power supply does not need to be disposed in the main body tubular part of the electronic pen main unit 3E, and therefore the configuration of the electronic pen main unit 3E can be simplified.

Because the secondary cell 12BT is used in the example of <FIG>, the electrodes 2Ed and 2Ee for charging are disposed on the pen casing 2E. However, a primary cell may be used instead of the secondary cell 12BT. In this case, the electrodes 2Ed and 2Ee for charging become unnecessary.

Next, <FIG> is a modification example of the electronic pen 1E of the example of <FIG>. In an electronic pen 1F of this example of <FIG>, only the charging method of the secondary cell 12BT disposed in a pen casing 2F is different from the electronic pen 1E, and the other configuration is similar to the electronic pen 1E.

In the electronic pen 1F of this example, as illustrated in <FIG>, a core <NUM> is fitted and attached to the outer circumferential side surface of the pen casing 2F, and a coil <NUM> for charging is wound and disposed around this core <NUM>. Furthermore, in the electronic pen 1F of this example, a configuration in which electromagnetic energy supplied from the external is received by the coil <NUM> for charging and the secondary cell 12BT is charged is made.

In the electronic pen 1F of this example, a movement mechanism has a configuration using a knock bar 42F of a slide system. A connector 90F for joining is formed at a fitting part 43F moved in response to slide movement of this knock bar 42F and is configured to be joined to a rear-end-part connector 50F of an electronic pen main unit 3F. Also in the electronic pen 1F of this example, a movement mechanism based on a knock bar pushed from the rear end side of the pen casing 2F like that illustrated in <FIG> may be used. Furthermore, also in the electronic pen 1E of the example of <FIG>, it is also possible to make the configuration in such a manner that a movement mechanism using a knock bar of a slide system like that in <FIG> is used. In addition, in the example of <FIG>, the secondary cell 12BT is disposed in the casing 2F of the electronic pen 1F. However, the configuration may be made in such a manner that a secondary cell is disposed in the electronic pen main unit 3F and is charged by a charging current from the charging coil <NUM>.

Moreover, an electronic pen <NUM> of an example of <FIG> is different from the electronic pen 1F of the example of <FIG> in that an electronic circuit <NUM> is disposed in a pen casing <NUM> and the side switch <NUM> is connected to the electronic circuit <NUM> through not a connector for joining but, for example, a flexible cable, and the others are made into a similar configuration. Furthermore, in the electronic pen <NUM> of this example, a connector <NUM> for joining and a rear-end-part connector <NUM> of an electronic pen main unit <NUM> are joined, and the electronic pen main unit <NUM> and electronic circuit components disposed on the pen casing <NUM> are electrically connected through a flexible cable or the like.

In the electronic pen <NUM> of this example, a voltage from the secondary cell 12BT disposed in the pen casing <NUM> is supplied to an electronic circuit of the electronic pen main unit <NUM> as a supply voltage similarly to the electronic pens 1E and 1F of the above-described examples. In addition, in the electronic pen <NUM> of this example, the voltage from the secondary cell 12BT is supplied to the electronic circuit <NUM> as a supply voltage.

In this electronic circuit <NUM>, a control part formed of an IC is disposed and a wireless communication part that carries out wireless communication of, for example, the Bluetooth (registered trademark) standard is disposed to be connected to the control part. This wireless communication part is what is for carrying out wireless communication between the electronic pen <NUM> and a position detecting device of a capacitive coupling system similarly to the above-described embodiments. Furthermore, the control part of the electronic circuit <NUM> is connected to a terminal part including a circular annular conductor contact part of the connector <NUM> for joining.

In addition, in the electronic pen <NUM> of this example, the side switch <NUM> is connected to the control part, and the configuration is made in such a manner that operation information of this side switch <NUM> is wirelessly transmitted to the position detecting device of the capacitive coupling system.

Moreover, in the electronic pen <NUM> of the example of <FIG>, the electronic circuit <NUM> disposed in the pen casing <NUM> is configured to acquire writing pressure information detected by the electronic circuit of the electronic pen main unit <NUM> through the rear-end-part connector <NUM> and the connector <NUM> for joining and wirelessly transmit the writing pressure information to the position detecting device of the capacitive coupling system. Therefore, the writing pressure information does not need to be included in a signal for position detection sent out from the core body <NUM> of the electronic pen main unit <NUM> of this example. Also in the electronic pen <NUM> of this example, the writing pressure information may be included in the signal for position detection sent out from the core body <NUM> of the electronic pen main unit <NUM> and be sent out.

Also in the electronic pen <NUM> of this example, a movement mechanism based on a knock bar pushed from the rear end side of the pen casing 2F like that illustrated in <FIG> may be used.

Furthermore, in the configuration of the electronic pen <NUM> of this example of <FIG>, it is also possible to make the configuration as follows by using the electronic circuit <NUM>.

Specifically, a memory that stores identification information (pen ID) of the electronic pen <NUM> may be disposed to be connected to the control part of the electronic circuit <NUM>, and a position detecting device may be notified of the pen ID through the wireless communication part.

Furthermore, a memory that stores identification information (pen main unit ID) of the electronic pen main unit <NUM> is disposed in the electronic circuit of the electronic pen main unit <NUM>, and the pen main unit ID in this memory is supplied to the electronic circuit <NUM> disposed in the pen casing <NUM> through the rear-end-part connector <NUM> and the connector <NUM> for joining. Then, this electronic circuit <NUM> may notify the pen main unit ID to the position detecting device through the wireless communication part.

Moreover, in the electronic circuit of the electronic pen main unit <NUM>, a signal sent out from a position detecting sensor of the position detecting device is received by the peripheral electrode <NUM>, and the signal level of the signal received by a receiving part thereof is detected. Then, it is detected whether the electronic pen <NUM> is in an in-range state in which the electronic pen <NUM> makes capacitive coupling with the position detecting sensor or an out-range state in which the electronic pen <NUM> is not coupled with the position detecting sensor, and a detection signal thereof is supplied to the electronic circuit <NUM> disposed in the pen casing <NUM> through the rear-end-part connector <NUM> and the connector <NUM> for joining. Then, this electronic circuit <NUM> may notify whether the electronic pen <NUM> is in the in-range state or the out-range state to the position detecting device through the wireless communication part.

In the above-described embodiments, the peripheral electrode is composed of a tubular conductor. However, the peripheral electrode may be what is configured into a tubular shape by a conductor divided into multiple pieces in the circumferential direction.

Furthermore, the core body <NUM> is composed of an electrically-conductive metal. However, it is sufficient for the core body <NUM> to be what has electrical conductivity. Therefore, the core body <NUM> may include a hard resin into which conductor powders are mixed, for example.

Claim 1:
An electronic pen main unit (<NUM>) that is to be fitted to a fitting part disposed in a casing (<NUM>) of an electronic pen (<NUM>) in which a pen tip side that is one end side in an axial center direction is made to be an opening, and is to be housed in a state of being movable in a hollow part of the casing (<NUM>) by a movement mechanism that moves the fitting part in the axial center direction of the casing (<NUM>), the electronic pen main unit (<NUM>) comprising:
a center electrode (<NUM>) being a core body and being composed of an electrically-conductive component,
a pen tip part including the electrically-conductive core body (<NUM>) allowed to protrude to external through the opening by being moved by the movement mechanism, wherein the opening is for inserting the core body (<NUM>) into a main unit casing (<NUM>);
the main unit casing (<NUM>) including a main body tubular part (<NUM>) to which the pen tip part is joined on the pen tip side in the axial center direction and that houses an electronic circuit including a signal generating circuit that generates a signal to be sent out to the external through the core body (<NUM>);
a rear-end-part connector that is disposed at a rear end part of the main body tubular part (<NUM>) on a side opposite to the pen tip part in the axial center direction, includes a terminal connected to the electronic circuit, and is joined to a connector for joining disposed at the fitting part of the casing (<NUM>); and
a core body holding component (<NUM>) being disposed in the main unit casing (<NUM>),
wherein an end part of the core body (<NUM>) is mounted to the core body holding component (<NUM>) attachably and detachably.