Electronic pen

Abstract

To improve the strength of a connection part between a cylindrical part made of a conductive material and a sleeve part made of a non-conductive material in an electronic pen provided with a housing in which the cylindrical part and the sleeve part are connected in an axial direction with the sleeve part being on a pen tip side.SOLUTION: A tip part includes a core body with conductivity to be disposed so as to be exposed through an opening provided on a pen tip side of a housing, and a peripheral electrode disposed so as to surround the core body around within a hollow part of the housing. The peripheral electrode is provided with an extension part extending from a hollow part of the sleeve part over to a hollow part of a cylindrical part across a connection part between the cylindrical part and the sleeve part. An insulating member for electrically separating the peripheral electrode from the cylindrical part is disposed in a space in which an outer peripheral surface of the extension part of the peripheral electrode faces an inner peripheral surface of the housing in a state in which an inner peripheral surface of the insulating member is brought into contact with the outer peripheral surface of the extension part of the peripheral electrode and an outer peripheral surface of the insulating member is brought into contact with the inner peripheral surface of the housing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an active capacitance type electronic pen having a conductive core body and a peripheral electrode. [Background technology]

[0002] In an active capacitance type electronic pen, a signal transmission circuit is provided on a circuit board provided inside the housing, and a signal from this signal transmission circuit is transmitted to a position detection sensor through a conductive core body. Also, an active capacitance type electronic pen is known that includes a peripheral electrode made of, for example, a conductive metal, surrounding the periphery of the portion of the core body that is present inside the housing (see, for example, Patent Document 1 (JP 2024-507791 A)).

[0003] Fig. 8 shows an example of the configuration of a conventional active capacitance type electronic pen 100 of this type. Fig. 8 is an enlarged cross-sectional view of the conventional electronic pen 100, from the core body 101 to the pen tip side portion of the circuit board 102.

[0004] The housing (hereinafter referred to as pen case) 103 of the electronic pen 100 in this example is configured by joining a cylindrical case part 1031 made of a conductive material with a fixed diameter, in this example made of a conductive metal, for example SUS, and a sleeve part 1032 configured in a tapered shape that tapers toward the pen tip side of the cylindrical case part 1031. The sleeve part 1032 is made of an insulating material, in this example made of resin.

[0005] The sleeve portion 1032 has a space that communicates with the hollow space of the cylindrical case portion 1031, and has an opening 1032a at its tapered tip end, which is an opening on the pen tip side of the pen case 103. The core body 101, which is configured to have conductivity, is attached to the electronic pen 100 with its tip end 101a protruding outward from the opening 1032a of the sleeve portion 1032.

[0006] A boat-shaped resin board holder 104, with its longitudinal direction aligned with the axis of the pen case 103, is disposed within the pen case 103 in a state where it cannot move in the axial direction. The board holder 104 has a board mounting portion, and a long, rectangular circuit board 102 is mounted on and held on the board mounting portion. Although not shown, the circuit board 102 is provided with a signal transmission circuit that transmits a signal to be sent to a position detection sensor of the position detection device through the core body 101. A cylindrical pressure detection unit holder portion 1041 is integrally formed on the pen tip side of the board holder 104.

[0007] In this example, the pressure detection unit holder 1041 houses the pressure detection unit 105. In this example, the pressure detection unit 105 is configured as a variable capacitance capacitor that detects the pressure (writing pressure) applied to the core body 101 as a change in capacitance (see, for example, Patent Document 2 (JP 2011-186803 A)). In this example, the pressure detection unit 105 is configured to include a dielectric 1051, a ring-shaped spacer 1052, and a conductive elastic member 1053.

[0008] That is, a variable capacitance capacitor is formed by a first electrode formed on one circular plane of dielectric 1051 and a second electrode made of conductive elastic member 1053 facing each other across a space in the center of dielectric 1051 and ring-shaped spacer 1052. The first electrode is electrically connected to circuit board 102 through electrode terminal 1054.

[0009] When conductive elastic member 1053 is pressed with a pressure corresponding to the pressure applied to core body 101, a central portion of the second electrode located in the central space of ring-shaped spacer 1052 elastically deforms toward dielectric 1051 and comes into contact with the pen tip side surface of dielectric 1051. The contact area of ​​the second electrode with dielectric 1051 at this time corresponds to the amount of pressure applied. In other words, the capacitance of a capacitor formed by dielectric 1051 and the first and second electrodes sandwiching dielectric 1051 changes as the contact area between the second electrode and dielectric 1051 changes depending on the pressure applied to conductive elastic member 1053. Therefore, the pressure (writing pressure) applied to core body 1051 can be detected by detecting the capacitance of this capacitor.

[0010] In this example, the conductive elastic member 1053 of the pressure detection unit 105 is configured to receive the pressure (writing pressure) applied to the tip of the core 101 via the core holder 106 and the pressure transmission member 107.

[0011] 8, the pressure transmitting member 107 in this example is made up of a pusher member 1071 and a pressing member 1072 that presses the pusher member 1071 in the axial direction, both of which are made of a non-conductive material, such as resin. The pusher member 1071 and pressing member 1072 are housed in a pressure transmitting member housing 108 in a state where they can move in the axial direction. The pressure transmitting member housing 108 is provided on the pen tip side of the pressure detecting unit holder portion 1041 of the board holder 104.

[0012] 8, the pressing member 1072 of the pressure transmission member 107 has a fitting recess 1072a on the pen tip side, and the rear end side of a holder main body 1061 (described later) of the core holder 106 is fitted into this fitting recess 1072a, thereby connecting the pressure transmission member 107 and the core holder 106 in the axial direction. The rear end of the core 101 is fitted into the pen tip side of the core holder 106, so that the pressure applied to the tip of the core 101 is transmitted to the pressure detection unit 105 via the core holder 106 and the pressure transmission member 107.

[0013] The core holder 106 has a conductive configuration, and in addition to transmitting the pressure applied to the tip 101a of the core 101 to the pressure transmission member, it also serves to electrically connect the conductive core 101 to the signal transmission circuit provided on the circuit board 102. As shown in FIG. 8, the core holder 106 is provided in a core holder storage section 109 provided on the pen tip side of the pressure transmission member storage section 108. The core holder storage section 109 is made of a non-conductive material, such as resin, and is configured to serve as a member for electrically separating (insulating) the conductive cylindrical case section 1031 from the conductive core holder 106.

[0014] In the example of Fig. 8, the core body 101 is configured such that most of the core body 101, except for the rear end side of the center electrode 1011 made of a conductive material, for example, a conductive metal, is covered with a protective member 1012 made of a non-conductive material. The rear end part of the core body 101 that is exposed and not covered by the protective member 1012 is configured to be fitted into a core body holder 106, as shown in Fig. 8. In this case, the core body 101 is detachable from the core body holder 106, and is replaceable.

[0015] The core holder 106 has a holder main body 1061 configured as a metal shaft made of a conductive material, in this example, a conductive metal, such as SUS, to electrically connect the core 101 and the signal transmission circuit of the circuit board 102. The holder main body 1061 has a fitting portion into which the rear end of the center electrode 1011 of the core 101 is fitted, and a conductive elastic holding member 1062 made of, for example, conductive rubber is disposed within the fitting portion. When the rear end of the center electrode 1011 of the core 101 is press-fitted into the fitting portion of the holder main body 1061, the rear end of the center electrode 1011 of the core 1011 is firmly held in the core holder 106 by the conductive elastic holding member 1062, ensuring electrical connection between the center electrode 1011 of the core 101 and the holder main body 1061.

[0016] The holder main body 1061 of the core holder 106 is configured as a metal shaft, and it is difficult to configure the pusher member 1071 of the pressure transmission member 107 to be directly pressed by the holder main body 1061. For this reason, in this example, as described above, the pressure transmission member 107 has a resin pressing member 1072 that presses the resin pressing member 1071, and the holder main body 1061, which is configured as a metal shaft, is fitted into this resin pressing member 1072.

[0017] 8, one end of a coil spring 1063 made of conductive metal is connected to a holder main body 1061 made of conductive metal, and the other end of the coil spring 1063 is connected to the circuit board 102 (not shown). Therefore, a signal from the signal transmission circuit of the circuit board 102 is sent through the coil spring 1063 to the core holder 106 and the central electrode 1011 of the core 101, and is configured to be sent to the position detection sensor side.

[0018] 8, in the electronic pen 100 of this example, a peripheral electrode 110 made of, for example, a conductive metal is provided in the hollow space of the sleeve portion 1032 on the pen tip side of the pen case 103 so as to surround the periphery of the rear end portion opposite the tip portion protruding to the outside of the core body 101. This peripheral electrode 110 is provided to receive signals from the position detection sensor and control the timing of signals exchanged with the position detection device, and to send signals to the position detection sensor so that the position detection device can detect the tilt of the electronic pen 1.

[0019] The peripheral electrode 110 is configured to have a hollow cylindrical shape with an outer circumferential side shape that fits along the inner wall surface of the sleeve portion 1032. The axial length of the peripheral electrode 110 is set to a length that allows it to be housed within the sleeve portion 1032, since it needs to be electrically separated and insulated from the conductive cylindrical case portion 1031.

[0020] 8, the peripheral electrode 110 is configured to be held relative to the core holder storage section 109 by having the pen tip side portion of the core holder storage section 109 press-fit into the hollow space of the peripheral electrode 110 from its rear end side. In this case, taking into consideration the slimming of the electronic pen 100, the portion of the peripheral electrode 110 into which the core holder storage section 109 is press-fitted is made thinner than the pen tip side of the peripheral electrode 110, and the pen tip side of the core holder storage section 109 is configured to fit into this thinner portion.

[0021] With this configuration, the core holder storage section 109 serves to ensure electrical insulation between the peripheral electrode 110 and the exposed rear end side of the center electrode 1011 of the core 101 and the conductive holder main body 1061 of the core holder 106. For this reason, the axial length of the thin-walled portion of the peripheral electrode 110 is set to a length that can ensure electrical insulation between the peripheral electrode 110 and the exposed rear end side of the center electrode 1011 of the core 101 and the conductive holder main body 1061 of the core holder 106.

[0022] The rear end of the core holder housing 109, which is not housed in the peripheral electrode 110, has an outer diameter that is approximately equal to the inner diameter of the cylindrical case 1031 and the inner diameter of the sleeve 1032, making it thick. Therefore, as shown in Fig. 8, this thick portion of the core holder housing 109 is in contact with the inner wall surfaces of the cylindrical case 1031 and the sleeve 1032. In this example, this thick portion of the core holder housing 109 is configured to straddle the joint between the cylindrical case 1031 and the sleeve 1032 in the axial direction, and thus the core holder housing 109 is configured to reinforce the strength of the joint between the cylindrical case 1031 and the sleeve 1032.

[0023] The peripheral electrode 110 is electrically connected to the circuit board 102 by a connection wire (not shown). One end of the electrical connection wire between the peripheral electrode 110 and the circuit board 102 is electrically connected to the rear end of the peripheral electrode 110. The other end of this connection wire needs to be extended to the circuit board 102, but needs to be arranged in a state where insulation is ensured between the peripheral electrode 110 and the cylindrical case part 1031. Therefore, for example, a recessed groove or a through hole is formed in the core holder storage part 109, and the core holder storage part 109 is penetrated and arranged between the peripheral electrode 110 and the circuit board 102. [Prior art documents] [Patent documents]

[0024] [Patent Document 1] Special Publication No. 2024-507791 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-186803 Summary of the Invention [Problem to be solved by the invention]

[0025] In the conventional electronic pen 100 described above, the peripheral electrode 110 is arranged to be housed within the hollow space of the sleeve portion 1032 so as to reliably ensure insulation from the conductive cylindrical case portion of the pen case 103. The pen tip side of the core holder storage portion 109, which is made of resin, is fitted over the rear end side of the peripheral electrode 110, thereby holding the peripheral electrode 110 in the core holder storage portion 109, and the core holder storage portion 109 is configured to abut against the inner wall surface of the pen case 103 while straddling the joint between the cylindrical case portion 21 and the sleeve portion 22, thereby reinforcing the strength of the joint between the cylindrical case portion 21 and the sleeve portion 22.

[0026] However, in the conventional electronic pen 100, as shown in Figure 8, the joint between the cylindrical case portion 21 and the sleeve portion 22 is reinforced only by the core holder storage portion 109 made of resin, so there was a risk that the strength would not be satisfactory.

[0027] SUMMARY OF THE INVENTION An object of the present invention is to provide an electronic pen that can solve the above problems. [Means for solving the problem]

[0028] To solve the above problems, a housing configured by joining a cylindrical portion made of a conductive material and a sleeve portion made of a non-conductive material, the sleeve portion having a hollow portion communicating with the hollow portion of the cylindrical portion, in an axial direction with the sleeve portion facing the pen tip; a conductive core body disposed so that a tip portion thereof is exposed to the outside through an opening provided on the pen tip side of the housing; a peripheral electrode disposed in the hollow portion of the housing so as to surround the periphery of the core body; Equipped with the peripheral electrode includes an extension portion that extends across a joint between the cylindrical portion and the sleeve portion, from the hollow portion of the sleeve portion to the hollow portion of the cylindrical portion, An insulating member that electrically separates the peripheral electrode from the cylindrical portion is disposed in a space where the outer peripheral surface of the extension portion of the peripheral electrode faces the inner peripheral surface of the housing, with the inner peripheral surface of the insulating member abutting against the outer peripheral surface of the extension portion of the peripheral electrode and the outer peripheral surface of the insulating member abutting against the inner peripheral surface of the housing. The present invention provides an electronic pen characterized by the above features.

[0029] In the electronic pen having the above-described configuration, the peripheral electrode has an extension that extends across the joint between the cylindrical portion and the sleeve portion that constitute the housing, from the hollow portion of the sleeve portion to the hollow portion of the cylindrical portion. An insulating member that electrically separates the peripheral electrode from the cylindrical portion is disposed in the space where the outer peripheral surface of the extension of the peripheral electrode faces the inner peripheral surface of the housing, with the inner peripheral surface of the insulating member abutting against the outer peripheral surface of the extension of the peripheral electrode and the outer peripheral surface of the insulating member abutting against the inner peripheral surface of the housing.

[0030] Therefore, in the electronic pen having the above-described configuration, not only the insulating member but also the extension of the peripheral electrode is present across the joint between the cylindrical portion and the sleeve portion that constitute the housing, and the insulating member and the extension of the peripheral electrode are configured to reinforce the joint between the cylindrical portion and the sleeve portion. Therefore, the electronic pen having the above-described configuration has improved strength at the joint between the cylindrical portion and the sleeve portion compared to the conventional electronic pen shown in FIG. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is a diagram illustrating an example of the configuration of an embodiment of an electronic pen according to the present invention; [Figure 2] 1 is a diagram illustrating an example of the configuration of an embodiment of an electronic pen according to the present invention; [Figure 3] 1 is a diagram illustrating an example of the configuration of a main part of an embodiment of an electronic pen according to the present invention; [Figure 4] 1 is a diagram illustrating an example of the configuration of a main part of an embodiment of an electronic pen according to the present invention; [Figure 5] 1 is a diagram illustrating an example of the configuration of a main part of an embodiment of an electronic pen according to the present invention; [Figure 6] 1 is a diagram illustrating an example of the configuration of a main part of an embodiment of an electronic pen according to the present invention; [Figure 7] 10A and 10B are diagrams illustrating an example of the configuration of another embodiment of an electronic pen according to the present invention. [Figure 8] FIG. 1 is a diagram illustrating an example of the configuration of a conventional electronic pen. DETAILED DESCRIPTION OF THE INVENTION

[0032] Hereinafter, an embodiment of an electronic pen according to the present invention will be described with reference to the drawings.

[0033] FIG. 1(A) is a side view of the external appearance of an example of an electronic pen 1 according to this embodiment. Also, FIGS. 1(B) and 2(A) are enlarged cross-sectional views of the pen tip side of the electronic pen 1 taken along line AA in FIG. 1(A). In this case, FIG. 1(B) is a view seen from a direction perpendicular to the thickness direction of a circuit board 34 (described later), and FIG. 2(A) is a view seen from above the board surface in the thickness direction of the circuit board 34. For convenience of illustration, the enlargement ratios are different between FIG. 1(B) and FIG. 2(A). FIG. 2(B) is an exploded perspective view illustrating the configuration of a pressure detection unit 9 and a pressure transmission member included in the electronic pen 1 according to this embodiment.

[0034] The electronic pen 1 of this embodiment is configured such that a main body unit 3 of an active capacitance type electronic pen and, in this example, a primary battery 4 are housed in the hollow space of a long, slender cylindrical housing (hereinafter referred to as a pen case) 2, as shown by the dotted line in Fig. 1(A). In this case, as shown by the dotted line in Fig. 1(A), in the electronic pen 1 of this embodiment, the main body unit 3 is disposed on the pen tip side in the axial direction of the hollow space of the pen case 2, and the primary battery 4 is disposed on the rear end side opposite the pen tip side.

[0035] The pen case 2 comprises a cylindrical portion of a constant diameter made of a conductive material, in this example a cylindrical case portion 21 made of a conductive metal such as SUS, a sleeve portion 22 connected to the pen tip side of the cylindrical case portion 21, and a rear end closing portion 23 connected to the rear end side of the cylindrical case portion 21 in the axial direction. The sleeve portion 22 and the rear end closing portion 23 are made of an insulating material, in this example a resin. In this embodiment, the cylindrical case portion 21 made of a conductive material is electrically connected to the earth conductor of the circuit board 34, which will be described later.

[0036] The sleeve portion 22 has a space that communicates with the hollow space of the cylindrical case portion 21, and is configured in a tapered shape that tapers toward the pen tip side, with the tip side of the tapered shape forming an opening 22a (see FIG. 1(B)). The opening 22a of the sleeve portion 22 is the opening on the pen tip side of the pen case 2. In the electronic pen 1 of this embodiment, the core body 5, which is configured to have conductivity, is attached to the pen tip side component 32 of the electronic pen 1, which will be described later, with its tip portion 5a protruding outward from the opening 22a of the sleeve portion 22.

[0037] The core body 5 in this embodiment has a configuration similar to that of the core body 101 of the electronic pen 100 shown in Fig. 8, and is configured such that most of the center electrode 51, made of a conductive material, except for the rear end side, is covered with a protective member 52 made of a non-conductive material. As shown in Figs. 1(B) and 2(A), the tip portion 5a of this core body 5 has a conical shape in which the egg-shaped portion of the center electrode 51 is covered with the protective member 52, having a tapered portion that tapers toward the tip side. As shown in Figs. 1(B) and 2(A), the rear end side of the tip portion 5a of the core body 5 has a diameter smaller than the diameter of the opening 22a of the sleeve portion 22, and the end portion of the center electrode 51 on the rear end side is not covered with the protective member 52 and is exposed.

[0038] In this example, as shown in FIGS. 1B and 2A, the core 5 has a structure in which a space (air layer) 53 is provided between the center electrode 51 and the protective member 52. The signal (electric field) radiated from the portion of the center electrode 51 of the core 5, which is located on the tip side of the wide portion of the egg-shaped pen tip, is radiated relatively efficiently only through the protective member 52. However, the radiation of the signal (electric field) from the narrow portion of the center electrode 51, which is located on the rear side of the egg-shaped pen tip, is suppressed by the action of the space 53 and the protective member 52. This is because the space 53 and the protective member 52 have different dielectric constants, and this portion functions like a double capacitor. As a result, even if the electronic pen 1 is tilted with respect to the input surface of the position detection sensor, the center electrode 51 can transmit a good signal without excessive broadening.

[0039] The rear end closing portion 23 is fitted and coupled to the cylindrical case portion 21 so as to close the opening on the rear end side of the cylindrical case portion 21. In this example, the rear end closing portion 23 includes a clip portion 23a as shown in FIG. 1(A), and is configured to be detachable from the cylindrical case portion 21.

[0040] In the electronic pen 1 of this embodiment, when the rear end closing portion 23 is removed from the cylindrical case portion 21, the primary battery 4 can be stored in and removed from the battery storage portion 4a inside the cylindrical case portion 21. Then, when the primary battery 4 is stored in the battery storage portion 4a inside the cylindrical case portion 21, the rear end closing portion 23 can be fitted into the cylindrical case portion 21, so that the primary battery 4 can be locked in the battery storage portion 4a inside the cylindrical case portion 21.

[0041] The main body unit 3 is arranged in a space on the pen tip side of the battery storage section 4a within the hollow section of the cylindrical case section 21, and is fixed in place within the hollow section of the pen case 2 so as not to move in the axial direction.

[0042] 1(A), the main body unit 3 in this example includes a boat-shaped resin unit holder 31 whose longitudinal direction coincides with the axial direction of the pen case 2, and a pen tip side component 32 is provided on the pen tip side of the unit holder 31. A board mounting portion 33 is provided between the pen tip side component 32 and the battery storage portion 4a of the unit holder 31, and a long, rectangular circuit board 34 is mounted on and held by the board mounting portion 33.

[0043] 1(A), the circuit board 34 is provided with a signal transmission circuit 340 that transmits a signal to be sent to the position detection sensor of the position detection device through the core body 5. The voltage from the primary battery 4 stored in the battery storage section 4a is supplied to the signal transmission circuit 340 as a power supply voltage.

[0044] Furthermore, in the electronic pen 1 of this embodiment, as will be described later, a peripheral electrode 6 (see FIGS. 1(B) and 2(A)) is provided in the hollow space on the pen tip side of the pen case 2 so as to surround the periphery of the rear end portion opposite the tip portion protruding to the outside of the core body 101. In this embodiment, this peripheral electrode 6 is configured to receive signals from the position detection sensor and control the timing of signals exchanged with the position detection device, and to send signals to the position detection sensor so that the position detection device can detect the tilt of the electronic pen 1.

[0045] [Example of internal configuration of the pen tip side of electronic pen 1] Next, an example of the internal configuration of the pen tip side of the electronic pen 1 of this embodiment will be described with reference to the enlarged cross-sectional views of the pen tip side in FIG. 1(B) and FIG. 2(A).

[0046] As shown in FIGS. 1(B) and 2(A), the sleeve portion 22 includes a tapered portion 22b that tapers toward the pen tip side and a constant diameter portion 22c whose outer and inner diameters are constant. The outer diameter of the constant diameter portion 22c of the sleeve portion 22 is configured to be equal to the outer diameter of the cylindrical case portion 21, and the inner diameter is equal to or slightly larger than the inner diameter of the cylindrical case portion 21. The sleeve portion 22 is coupled to the pen tip side of the cylindrical case portion 21 at the constant diameter portion 22c side to form the pen case 2. As shown in FIGS. 1(B) and 2(A), the hollow space of the sleeve portion 22 forms a space that communicates with the hollow space of the cylindrical case portion 21. Furthermore, as shown in FIGS. 1(B) and 2(A), the pen tip side component 32 of the main body unit 3 is provided in a space spanning the hollow space of the cylindrical case portion 21 and the hollow space of the sleeve portion 22.

[0047] In this embodiment, as shown in Figures 1(B) and 2(A), the pen tip side component 32 holds a peripheral electrode 6 on the pen tip side, and is configured to include a core holder 7, a pressure transmission member 8, a pressure detection unit (pen pressure detection unit) 9, and a core 5 that is detachably attached to the core holder 7.

[0048] The pressure detection unit 9 is housed in a cylindrical pressure detection unit holder part 311 provided on the pen tip side of the unit holder 31. In this embodiment, the pressure detection unit holder part 311 is configured integrally with the unit holder 31.

[0049] In this embodiment, the pressure detection unit 9 has the same configuration as the pressure detection unit 105 described above, and is configured as a variable capacitance capacitor that detects the pressure (writing pressure) applied to the core body 5 as a change in capacitance, and as shown in Figures 1(B), 2(A) and 2(B), is configured with a disk-shaped dielectric 91 of a predetermined diameter, a ring-shaped spacer 92, and a thin disk-shaped conductive elastic member 93.

[0050] The dielectric 91 is disposed so that its thickness direction is in the axial direction of the pen case 3, and a first electrode is provided on the circular plane opposite the pen tip side of the two circular planes that face each other across the thickness portion. This first electrode is electrically connected to the circuit board 34 via an electrode terminal 94.

[0051] Spacer 92 is made of a circular, ring-shaped non-conductive material, and the outer diameter of the ring is equal to the diameter of dielectric 91. Conductive elastic member 93 is made of a conductive material, such as conductive rubber, and in this example is shaped like a predetermined thin disk with a diameter equal to that of dielectric 91. This conductive elastic member 93 forms a second electrode, and is connected to circuit board 34 via coil spring 95 made of conductive metal.

[0052] Thus, in the pressure detection unit 9, similar to the pressure detection unit 105 described above, a variable capacitance capacitor is formed by a first electrode formed on one circular plane of the dielectric 91 and a second electrode made of a conductive elastic member 93 facing each other across a space in the center of the dielectric 91 and the ring-shaped spacer 92.

[0053] Then, similar to the pressure detection unit 105 described above, the conductive elastic member 93 of the pressure detection unit 9 receives the pressure (writing pressure) applied to the tip 5a of the core 5 via the core holder 7 and the pressure transmission member 8, and the central portion located in the central space of the ring-shaped spacer 92 elastically deforms toward the dielectric 91, coming into contact with the pen tip side surface of the dielectric 91. The capacitance of the variable capacitance capacitor, which is composed of the dielectric 91 and the first and second electrodes sandwiching the dielectric 91, changes depending on the contact area between the second electrode and the dielectric 91 in response to the pressure applied to the conductive elastic member 93, so that the pressure (writing pressure) applied to the core 5 can be detected by detecting the capacitance of this variable capacitance capacitor.

[0054] The pressure transmitting member 8 is made of a non-conductive material, such as resin, and in this embodiment, it is composed only of a pusher member that presses the conductive elastic member 93 of the pressure detecting unit 9. In this example, the pusher member that constitutes the pressure transmitting member 8 has a large diameter portion 8a whose tip bulges out like a dome toward the pressure detecting unit 9, and a small diameter portion 8b that is smaller in diameter than the large diameter portion 8a, as shown in Figures 1(B), 2(A), and 2(B). The small diameter portion 8b of the pressure transmitting member 8 also has a dome-shaped bulge on the pen tip side. In this embodiment, the core holder 7 is configured to engage with the pen tip side of the small diameter portion 10b of the pressure transmitting member 8 that is made of this pusher member, and to act as a pressing member that presses the pressure transmitting member 8.

[0055] 1(B), a pressure transmission member storage section 10 made of a non-conductive material, such as resin, is provided on the pen tip side of the unit holder 31. The pressure transmission member 8 is disposed in this pressure transmission member storage section 10 so as to be movable in the axial direction, and the engagement portion between the pressure transmission member 8 and the core holder 7 is also housed in the pressure transmission member storage section 10. In this case, a through-hole 10a is provided in the pressure transmission member storage section 10, the diameter of which is larger than the diameter of the small diameter portion 8b of the pressure transmission member 8 but smaller than the diameter of the large diameter portion 8a. The pressure transmission member 8 is disposed such that the small diameter portion 8b is inserted into the through-hole 10a of the pressure transmission member storage section 10, and the large diameter portion 8a protrudes toward the pressure detection unit 9 beyond the pressure transmission member storage section 10, so that the tip of the large diameter portion 8a abuts against the conductive elastic member 93 of the pressure detection unit 9.

[0056] In this embodiment, the electrical connection between the second electrode of the pressure detection unit 9 and the circuit board 34 is made through a ring-shaped electrode plate 96 arranged on the rear end side of the pressure transmission member storage unit 10, as shown in Figures 1(B), 2(A) and 2(B).

[0057] 1(B), 2(A), and 2(B), in this embodiment, a small diameter portion 10b having a smaller diameter than the other portions is provided on the end face portion of the pressure transmitting member housing 10 on the pressure detecting unit 9 side so as to protrude toward the pressure detecting unit 9. Therefore, a ring-shaped end face is formed around the small diameter portion 10b on the end face portion of the pressure transmitting member housing 10 on the pressure detecting unit 9 side. The outer diameter of this small diameter portion 10b is selected to be larger than the diameter of the large diameter portion 8a of the pressure transmitting member 8.

[0058] The inner diameter of the wound portion of the coil spring 95 is larger than the small diameter portion 10b of the pressure transmission member accommodating portion 10, and smaller than the outer diameter of the ring-shaped end surface around the small diameter portion 10b of the pressure transmission member accommodating portion 10. In this embodiment, a ring-shaped electrode plate 96 (see FIG. 2(B)) having a size corresponding to the ring-shaped end surface around the small diameter portion 10b of the pressure transmission member accommodating portion 10 is disposed on the ring-shaped end surface around the small diameter portion 10b of the pressure transmission member accommodating portion 10, as shown in FIGS. 1(B) and 2(A).

[0059] 2(A) and 2(B), the ring-shaped electrode plate 96 has a lead plate portion 96a extending in the axial direction, and the tip portion of this lead plate portion 96a is, for example, soldered to the circuit board 34 and electrically connected to the conductor pattern of the circuit board 34, as shown in FIG. 2(A). The coil spring 95 is disposed between the conductive elastic member 93 of the pressure detecting unit 9 and the ring-shaped electrode plate 96 so as to be wound around the large diameter portion 8a of the pressure transmitting member 8 and the small diameter portion 10b of the pressure transmitting member housing portion 10, and is configured to electrically connect the conductive elastic member 93 and the ring-shaped electrode plate 96.

[0060] In this embodiment, the core holder 7 has the role of holding the core 5 by ensuring electrical connection with the center electrode 51 of the core 5, and when pressure is applied to the tip 5a of the core 5, it displaces axially together with the core 5 to transmit the pressure to the pressure detection unit 9 via the pressure transmission member 8, and also has the role of providing electrical connection between the center electrode 51 of the core 5 and the signal transmission circuit 340 arranged on the circuit board 34.

[0061] The core holder 7 is made of a conductive shaft member 70 made of a conductive resin, in this example, a resin mixed with conductive metal powder. One end of a coil spring 71 made of a conductive metal is electrically connected to the conductive shaft member 70 that constitutes the core holder 7.

[0062] 1(B) and 2(A), the core holder 7 is provided with a fitting recess 70a on the pen tip side of the conductive shaft member 70 into which the rear end side of the center electrode 51 of the core 5 is fitted. The exposed portion of the center electrode 51 on the rear end side of the core 5 is press-fitted into the fitting recess 70a of the conductive shaft member 70, whereby the core 5 is elastically held and locked in the core holder 7.

[0063] In this embodiment, as shown in Fig. 3, two slits 70b, which are cut in the axial direction, are formed at positions spaced apart by an angular interval of 180 degrees in the fitting recess 70a of the conductive shaft member 70 constituting the core holder 7. The diameter of the rear end of the center electrode 51 of the core 5 is selected to be equal to the diameter of the fitting recess 70a.

[0064] Therefore, when the rear end of the center electrode 51 of the core 5 is inserted into and fitted into the fitting recess 70a of the conductive shaft member 70, the presence of the slit 70b causes the center electrode 51 to be press-fit, and in this press-fit state, the elasticity of the conductive shaft member 70 ensures that the center electrode 51 of the core 5 is firmly held in the core holder 7. Note that while the core 5 is held in the core holder 7, it can be removed from the core holder 7 by pinching and pulling out the pen tip portion, for example, by hooking it with a fingernail. In other words, the core 5 is replaceable.

[0065] In this embodiment, a ring-shaped recessed groove 70c is provided on the outer periphery of the conductive shaft member 70 of the core holder 7 in the axial center, as shown in Fig. 3. The coil spring 71 made of conductive metal has an inner diameter of the wound portion that is larger than the outer diameter of the conductive shaft member 70, but the wound diameter of one end 71a on the pen tip side is made approximately equal to the diameter of the recessed groove 70c.

[0066] 1(B), 2(B), and 4, the coil spring 71 is disposed around the conductive shaft member 70 at a portion closer to the pressure detection unit 9 than the recessed groove 70c, and one end 71a of the coil spring 71 on the pen tip side is inserted into the recessed groove 70c. In this state, the elastic ring-shaped member 72 is fitted into the recessed groove 70c of the conductive shaft member 70. As a result, the one end 71a of the coil spring 71 is locked in a state of maintaining electrical connection with the conductive shaft member 70. Note that FIG. 4 is a longitudinal cross-sectional view of the conductive shaft member 70, on which the insulating cap member 12 described below is attached on the pen tip side, cut along a cut surface along the axial direction.

[0067] The other end 71b of the coil spring 71 extends in the axial direction away from the pen tip side, as shown in Figures 3 and 4. This extended other end 71b of the coil spring 71 is electrically connected, for example, by soldering to the conductor pattern of the circuit board 34, as shown in Figures 1(B), 2(B) and 5.

[0068] In this embodiment, as shown in FIGS. 2A and 3, the outer periphery of the conductive shaft member 70 on the side where the conductive shaft member 70 is coupled to the pressure transmission member 8 is provided with two sliding guide protrusions 70d, 70d that protrude from the outer periphery in a direction perpendicular to the axial direction and are positioned 180 degrees apart from each other. Meanwhile, as shown in FIGS. 2A and 5, the pressure transmission member storage section 10 is formed with guide grooves 10c, 10c into which the protrusions 70d, 70d of the conductive shaft member 70 are slidably inserted and engaged. The conductive shaft member 70 is disposed within the pressure transmission member storage section 10 with its protrusions 70d, 70d inserted into the two guide grooves 10c, 10c of the pressure transmission member storage section 10 in a state where it can move axially. This allows the conductive shaft member 70 to move axially stably within the hollow space of the pressure transmission member storage section 10 and to press the pressure transmission member 8 stably.

[0069] 1(B), 2(A), and 4, the tip of the conductive shaft member 70 on the pressure transmission member 8 side has a recess that engages with the dome-shaped bulge of the small-diameter portion 8b of the pressure transmission member 8. The recess of the conductive shaft member 70 is conical, with its apex at the bottom of the recess. With this configuration, even if the direction of the pressure transmitted from the conductive shaft member 70 to the pressure transmission member 8 deviates slightly from the axial direction, the pressure transmission member 8 always presses the vicinity of the center position of the conductive elastic member 93, and the pressure applied to the tip portion 5a of the core body 5 is transmitted to the pressure detection unit 9 effectively.

[0070] On the pen tip side of the conductive shaft member 70 that constitutes the core holder 7, a fitting recess 70a is formed to fit the conductive center electrode 51 of the core 5, as shown in Figures 1(B), 2(A) and 4.

[0071] In this embodiment, the portion of the conductive shaft member 70 that constitutes the core holder 7 that is closer to the pen tip than the portion that engages with the pressure transmission member 8 is accommodated within the hollow space of the peripheral electrode 6. That is, in this embodiment, the core holder accommodating section 109 shown in Figure 8 and made of resin, which is an insulating material, is not provided, and the peripheral electrode 6 is configured to serve as the core holder accommodating section.

[0072] The peripheral electrode 6 is cylindrically formed from a conductive material, such as a conductive metal (e.g., SUS), and in this example serves as an electrode that receives signals from the position detection sensor and transmits signals to the position detection sensor.

[0073] The peripheral electrode 6 includes a tapered portion 6a having an outer circumferential shape that conforms to the inner wall surface of the tapered portion 22b of the sleeve portion 22, and a rear end portion 6b having an outer circumferential shape that conforms to the inner wall surface of the constant diameter portion 22c of the sleeve portion 22. In this embodiment, the peripheral electrode 6 includes an extension portion 6c that extends further axially from the rear end portion 6b and reaches into the hollow space of the cylindrical case portion 21. That is, the extension portion 6c of the peripheral electrode 6 is disposed across the joint between the cylindrical case portion 21 and the sleeve portion 22, as shown in FIGS. 1(B), 2(B), and 7.

[0074] As shown in Figures 1(B) and 2(A), the outer diameter of the extension 6c of the peripheral electrode 6 is selected to be smaller than the inner diameter of the sleeve portion 22 and the cylindrical case portion 21, so that a space of a predetermined thickness is formed between the inner wall surfaces of the sleeve portion 22 and the cylindrical case portion 21 and the extension 6c of the peripheral electrode 6.

[0075] In this embodiment, as shown in FIGS. 1(B) and 2(A), an insulating member 11 made of an insulating material, for example, resin, is disposed between the extension 6 c of the peripheral electrode 6 and the inner wall surface of the housing 2 (the inner wall surfaces of the sleeve portion 22 and the cylindrical case portion 21). The insulating member 11 is configured in a cylindrical shape with an inner diameter equal to or slightly larger than the diameter of the extension 6 c of the peripheral electrode 6 and an outer diameter equal to or slightly smaller than the inner diameters of the sleeve portion 22 and the cylindrical case portion 21. Therefore, the insulating member 11 is disposed such that its inner circumferential surface abuts on the outer circumferential surface of the extension 6 c of the peripheral electrode 6, and its outer circumferential surface abuts on the inner circumferential surface of the cylindrical case portion 21 and the inner wall surfaces of the constant diameter portion 22 c of the sleeve portion 22.

[0076] As described above, the insulating member 11 is arranged in the axial direction, spanning the sleeve portion 22 and the cylindrical case portion 21, and in this embodiment, the inner surfaces of the sleeve portion 22 and the cylindrical case portion 21 are joined to the outer surface of the insulating member 11 with an adhesive to form the pen case 2.

[0077] The insulating member 11 is configured to hold the peripheral electrode 6 by accommodating the extension 6c of the peripheral electrode 6 in the hollow space on the pen tip side. In other words, the insulating member 11 serves as a peripheral electrode holding member that holds the peripheral electrode 6.

[0078] In this embodiment, the peripheral electrode 6 is electrically connected to the circuit board 34 using a lead member 61, as shown in Fig. 6. In this embodiment, as shown in Figs. 1(B), 2(A), and 6(A) to (C), a ring-shaped recessed groove 6d is provided between the rear end side portion 6b and the extension portion 6c of the peripheral electrode 6. As shown in Figs. 6(A) to (C), the lead member 61 is made of a single metal conductor, and includes a loop portion 61a that fits into the ring-shaped recessed groove 6d, and an extension portion 61b that extends from the loop portion 61a in a direction perpendicular to the loop plane.

[0079] The inner diameter of the loop portion 61a of the lead member 61 is formed to be equal to or slightly larger than the diameter of the bottom of the groove 6d of the peripheral electrode 6, and the loop portion 61a of the lead member 61 is attached by inserting it from the extension portion 6c side of the peripheral electrode 6 using a jig 62 having a conical portion as shown in Figure 6(B).

[0080] 6(C), the insulating member 11 is attached so as to cover the extension 6c of the peripheral electrode 6. At this time, the extension 61b of the lead member 61 passes through the inside of the insulating member 11. In this attached state, the ring-shaped protrusion 11a on the inner peripheral edge on the pen tip side of the insulating member 11 fits into the ring-shaped recessed groove 6d of the peripheral electrode 6 and elastically presses down on the loop portion 61a of the lead member 61, thereby locking the loop portion 61a of the lead member 61 onto the peripheral electrode 6 and ensuring electrical connection therebetween.

[0081] As shown in Figures 1(B), 2(A), and 7, the insulating member 11 has a portion further rearward than the extension 6c of the peripheral electrode 6. As shown in Figure 6(D), the insulating member 11 is engaged with the pressure transmission component accommodating portion 10 in a state in which the pen tip side of the pressure transmission component accommodating portion 10 is accommodated in this rear portion. In this case, as shown in Figures 1(B), 6(D), and 7, an engaging protrusion 10d is formed on the outer circumferential surface of the pressure transmission component accommodating portion 10, and a window portion 11b of a through hole with which the engaging protrusion 10d engages is formed in the rear portion of the insulating member 11. When the pen tip side of the pressure transmission component accommodating portion 10 is inserted into the insulating member 11, the engaging protrusion 10d engages with the window portion 11b of the through hole, and the two are joined together.

[0082] In this case, the extension portion 61b of the lead member 61 is extended to the circuit board 34 through the pressure detection unit holder portion 311 and is soldered to be electrically connected. As a result, the peripheral electrode 6 and the circuit board 34 are electrically connected through the lead member 61.

[0083] As described above, the insulating member 11 ensures electrical insulation between the conductive cylindrical case portion 21 and the extension portion 6c of the peripheral electrode 6, and also serves to suppress capacitive coupling between the cylindrical case portion 21 and the peripheral electrode 6. The insulating member 11 also serves as a peripheral electrode holding member that holds the peripheral electrode 6. Furthermore, since the insulating member 11 is disposed across the joint between the cylindrical case portion 21 and the sleeve portion 22, it serves to reinforce the joint between the cylindrical case portion 21 and the sleeve portion 22, in combination with the rigidity of the extension portion 6c of the peripheral electrode 6, which is made of metal in this example.

[0084] In this embodiment, as shown in Figures 1(B) and 2(A), the hollow space of the peripheral electrode 6 contains the rear end side of the tip portion 5a of the core body 5 inserted through the opening 22a of the sleeve portion 22, the fitting portion between the rear end side of the core body 5 and the conductive shaft member 70 that constitutes the core body holder 7, and a portion excluding the vicinity of the engagement portion of the conductive shaft member 70 with the pressure transmission member 8.

[0085] 1(B), the rear end side of the tip end 5a of the core body 5 is inserted into the internal space of the peripheral electrode 6 inside the pen case 2 through the opening 22a of the sleeve portion 22. Then, the rear end of the center electrode 51, which is exposed and not covered by the protective member 52, is fitted into the fitting recess 70a of the conductive shaft member 70 that constitutes the core body holder 7. In this case, the non-conductive protective member 52 of the core body 5 serves as a member for insulating the center electrode 51 and the peripheral electrode 6.

[0086] In this embodiment, when the core 5 is inserted into the sleeve portion 22 of the pen case 2, as shown in FIG. 1(B), the pen tip-side tip 6e of the peripheral electrode 6 abuts against the side circumferential surface of the protective member 52 at the small-diameter portion behind the tip 5a of the core 5, restricting the core 5 from moving in a direction perpendicular to the axial direction at the abutting portion. Because of this configuration, the pen tip-side tip 6e of the peripheral electrode 6 protrudes inward as shown in FIG. 1(B), and the size of the pen tip-side opening of the peripheral electrode 6 is configured to be approximately equal to or slightly larger than the diameter of the abutting portion of the core 5. This prevents the core 5 from rattling in a direction perpendicular to the axial direction at the pen tip-side opening of the peripheral electrode 6.

[0087] In this embodiment, the core holder 7 is made up of a conductive shaft member 70 and is disposed in the hollow space of the peripheral electrode 6, so it is necessary to ensure insulation between the conductive shaft member 70 and the peripheral electrode 6. For this reason, in this embodiment, a predetermined length of the conductive shaft member 70 in the axial direction on the side where it is fitted with the rear end of the center electrode 51 of the core 5 is covered with an insulating cap member 12 made of a non-conductive member, for example, a resin, as shown in Figures 1(B), 2(A) and 4, to ensure insulation between the peripheral electrode 6 and the conductive shaft member 70.

[0088] 1(B), 2(A), and 4, the insulating cap member 12 is configured in a cap shape with a recess 12a having a depth that covers a portion of the conductive shaft member 70 on the pen tip side, the portion having a predetermined length in the axial direction. In this embodiment, the predetermined length on the pen tip side of the conductive shaft member 70 is the portion in the axial direction that extends from the tip of the conductive shaft member 70 on the pen tip side to just before the position of the ring-shaped recessed groove 70c. Alternatively, the predetermined length on the pen tip side of the conductive shaft member 70 may be configured to include the position of the ring-shaped recessed groove 70c, so that the side wall of the recess 12a of the insulating cap member 12 covers the recessed groove 70c, thereby engaging and fixing the coil spring 71 to the recessed groove 70c.

[0089] The diameter of the recess 12a of the insulating cap member 12 is selected to be equal to or slightly larger than the diameter of a predetermined length portion on the pen tip side of the conductive shaft member 70. A through hole 12b having a diameter equal to or slightly larger than the diameter of the fitting recess 70a of the conductive shaft member 70 is formed in the bottom of the recess 12a of this insulating cap member 12 (the surface on the pen tip side in a direction perpendicular to the axial direction of the insulating cap member 12).

[0090] In this embodiment, as shown in Figures 2(A), 4, and 5, the side wall of the recess 12a of the insulating cap member 12 is formed with window portions 12c consisting of through holes at positions spaced 180 degrees apart. Meanwhile, an engaging protrusion 70e is formed on the outer periphery of a predetermined length portion of the conductive shaft member 70 on the pen tip side so as to fit into the window portion 12c of the through hole of the insulating cap member 12 when the conductive shaft member 70 is inserted into the recess 12a of the insulating cap member 12. When the insulating cap member 12 is placed over the predetermined length portion of the conductive shaft member 70 on the pen tip side so as to accommodate it in the recess 12a, the engaging protrusion 70e of the conductive shaft member 70 fits into the window portion 12c of the insulating cap member 12, and the two are joined so as not to easily come apart.

[0091] 1(B) and 2(A), the core body 5 is attached to the electronic pen 1 by press-fitting the rear end of its center electrode 51 into the fitting recess 70a of the conductive shaft member 70 through the through-hole 12b of the insulating cap member 12. When pressure is applied to the tip end 5a of the core body 5, the conductive shaft member 70 is displaced axially together with the core body 5, thereby transmitting the pressure to the pressure detection unit 9 via the pressure transmission member 8. As described above, the conductive shaft member 70 serves to electrically connect the center electrode 51 of the core body 5 and the signal transmission circuit 340 disposed on the circuit board 34.

[0092] As described above, in the electronic pen 1 of this embodiment, the peripheral electrode 6 is disposed across the joint between the cylindrical case portion 21 and the sleeve portion 22 that constitute the pen case 2, from the hollow portion of the sleeve portion 22 to the hollow portion of the cylindrical portion 21. In the space where the outer peripheral surface of the extension portion 6c at the rear end of the peripheral electrode 6 opposite the pen tip side faces the inner peripheral surfaces of the cylindrical portion 21 and the sleeve portion 22 of the pen case 2, an insulating member 11 that electrically separates the peripheral electrode 6 from the cylindrical case portion 21 is disposed with its inner peripheral surface abutting the outer peripheral surface of the extension portion 6c of the peripheral electrode 6 and its outer peripheral surface abutting the inner peripheral surface of the cylindrical case portion.

[0093] Therefore, in the electronic pen 1 of the above-described embodiment, not only the insulating member 11 but also the extension 6c of the peripheral electrode 6 is present across the joint between the cylindrical case portion 21 and the sleeve portion 22 that constitute the pen case 2, and the insulating member 11 and the extension 6c of the peripheral electrode 6 are configured to reinforce the joint between the cylindrical case portion 21 and the sleeve portion 22. Therefore, according to the electronic pen 1 of this embodiment, the strength of the joint between the cylindrical case portion 21 and the sleeve portion 22 can be improved compared to the conventional electronic pen shown in FIG.

[0094] In the electronic pen 1 of the above-described embodiment, the peripheral electrode 6 is held by an insulating member 11 disposed in the space between the extension 6c of the peripheral electrode 6 and the inner circumferential surface of the sleeve portion 22 and cylindrical case portion 21 of the pen case 2, and the insulating member 11 also ensures insulation between the conductive cylindrical case portion 21 and the peripheral electrode 6. Therefore, in the hollow space of the peripheral electrode 6, there is no need to provide the core holder storage portion 109 in contact with the inner wall surface of the peripheral electrode 110 in the hollow space of the peripheral electrode 110 as in the conventional electronic pen 100 described in FIG. 8. This allows the diameter of the peripheral electrode to be reduced accordingly, and the thickness of the electronic pen 1 can be made thinner.

[0095] Furthermore, in the electronic pen 1 of this embodiment, the core holder 7 is configured with the conductive shaft member 70, which makes it possible to solve the following problems with the conventional electronic pen 100 shown in FIG.

[0096] That is, the conventional electronic pen 100 shown in FIG. 8 uses a holder body 1061 that is made up of a metal shaft, which makes it costly, but in the electronic pen 1 of this embodiment, the core holder 7 is made up of a conductive shaft member 70 that is made up of conductive resin, which reduces costs.

[0097] Furthermore, in the conventional electronic pen 100 shown in Figure 8, the holder body 1061, which is made up of a metal shaft, was difficult to process, but in the electronic pen 1 of this embodiment, the core body holder 7 is made up of a conductive shaft member 70 made of conductive resin, making it easy to process.

[0098] 8, it was difficult to stably fit the rear end of a core made of conductive metal into the holder main body 1061, which has a metal shaft configuration, and therefore it was necessary to store a conductive elastic holding member 1062 in the fitting portion of the holder main body 1061. In contrast, in the electronic pen 1 of this embodiment, the core holder 7 is formed of a conductive shaft member 70 made of conductive resin, and therefore the rear end of the center electrode 51 of the core 5 can be directly fitted into the fitting recess 70a of the conductive shaft member 70, thereby holding the core 5 in the core holder 7. Therefore, in the electronic pen 1 of this embodiment, it is not necessary to store the conductive elastic holding member 1062 in the fitting portion of the holder main body 1061, which is beneficial for making the electronic pen 1 thinner.

[0099] 8 uses holder main body 1061 having a metal shaft, and therefore the pressure transmission member requires a pressing member made of resin that presses the pusher member that applies pressure to the pressure detection unit. In contrast, in electronic pen 1 of this embodiment, core holder 7 is made of conductive shaft member 70 made of conductive resin, and therefore the conductive shaft member 70 can be configured to directly press the pusher member that transmits pressure to pressure detection unit 9. That is, in electronic pen 1 of this embodiment, pressure transmission member 8 can be configured only as a pusher member, which simplifies the configuration and reduces costs.

[0100] Furthermore, in the electronic pen 1 of the above-described embodiment, an insulating cap member 12 is placed on the mating side of the conductive shaft member 70 with the rear end of the center electrode 51 of the core 5 to ensure electrical insulation between the peripheral electrode 6, so that the core holder storage section 109 made of a non-conductive member provided between the peripheral electrode 110 and the conductive core holder 106 in the conventional electronic pen 100 shown in Fig. 8 is not necessary. This contributes to making the electronic pen 1 slimmer.

[0101] [Other embodiments] 1(B) and 2(A), in the above-described embodiment, the insulating cap member 12 is configured to cover the pen tip side portion where the fitting recess 70a of the conductive shaft member 70 constituting the core holder 7 is formed, and a part of the rear end portion of the center electrode 51 of the core 5 is exposed. Therefore, if water droplets get into the exposed portion of the peripheral electrode 6 and the center electrode 51 of the core 5, there is a problem that an electrical short circuit occurs between them.

[0102] FIG. 7 shows an example of an electronic pen 1′ that solves this problem. In the electronic pen 1′ shown in FIG. 7, an insulating cap member 12′ that covers the pen tip side of the conductive shaft member 70 that constitutes the core holder 7 is configured to also cover the exposed portion of the center electrode 51 of the core 5 that is not fitted into the core holder 7. That is, as shown in FIG. 7, the insulating cap member 12′ also has a cup-shaped portion 12d that has a recess on the pen tip side. The recess of this cup-shaped portion 12d is deep enough to cover the exposed portion of the center electrode 51 of the core 5 that is not fitted into the core holder 7, as shown in FIG. 7, when the rear end of the center electrode 51 of the core 5 is fitted into the fitting recess 70a of the conductive shaft member 70 of the core holder 7, as well as to cover a portion of the protective member 52 of the core 5. Note that the configuration of the other components in FIG. 7 is the same as that shown in FIG. 1(B).

[0103] With this configuration, in the electronic pen 1' of the example of Figure 7, the entire rear end of the central electrode 51 of the core body 5 that is not covered by the protective member 52 is in a state where an insulating member is interposed between it and the peripheral electrode 6, and even if water droplets get between the peripheral electrode 6 and the core body 5, there is no problem of an electrical short circuit between them.

[0104] [Other embodiments or modifications] In the above embodiment, the tapered portion 6a and the rear end side portion 6b of the peripheral electrode 6, excluding the extension portion 6c, are configured so that their outer circumferential surfaces contact the inner wall surface of the sleeve portion 22, but there may be a gap between them and the inner wall surface of the sleeve portion 22. However, if the tapered portion 6a and the rear end side portion 6b of the peripheral electrode 6, excluding the extension portion 6c, are configured so that they contact the inner wall surface of the sleeve portion 22, as in the above embodiment, the strength of the sleeve portion 22 of the pen case 2 is improved, and the pen case 2 can be made thinner since there is no gap.

[0105] In the above-described embodiment, the peripheral electrode 6 is configured such that the extension 6c is thinner than the rear end portion 6b to ensure a space for disposing the insulating member 11. However, the peripheral electrode 6 may be configured with a metal having the same thickness as the extension 6c. In this case, the peripheral electrode 6 may be configured such that the extension 6c is bent relative to the rear end portion 6b to provide a space for inserting the insulating member 11, so that the tapered portion 6a and the rear end portion 6b contact the inner wall surface of the sleeve portion 22. Alternatively, the rear end portion 6b may be extended straight to form the extension 6c, so that a gap is formed between the rear end portion 6b and the sleeve portion 22. In the latter case where a gap is formed between the rear end portion 6b of the peripheral electrode 6 and the sleeve portion 22, the tapered portion 6a of the peripheral electrode 6 may contact the inner wall surface of the sleeve member 22, or a gap may be formed between the rear end portion 6b and the sleeve portion 22.

[0106] In the above-described embodiment, the pressure detection unit 9 has a configuration in which a conductive elastic member 93 is disposed on a disk-shaped dielectric 91 via a spacer 92, and the pressure applied is detected by detecting the capacitance corresponding to the contact area between the conductive elastic member 93 and the dielectric 91. However, the present invention is not limited to this configuration. For example, the pressure detection unit may be configured as a semiconductor device in which the distance between two electrodes facing each other via an air layer, which is a dielectric, changes according to the applied pressure (see, for example, Japanese Patent Application Laid-Open No. 2013-161307).

[0107] In addition, a pressure detection unit that detects the axial displacement of the core body in response to applied pressure as a change in inductance value (see, for example, JP 2017-216002 A) or a pressure detection unit that detects the axial displacement of the core body in response to applied pressure as a change in resistance value (see, for example, JP 2019-016038 A) may be used.

[0108] Furthermore, in the above-described embodiment, the pressure applied to the tip portion 5 a of the core 5 is transmitted to the pressure detection unit 9 via the core holder 7 and the pressure transmission member 8. However, since the core holder 7 is formed of a conductive shaft member 70, the pressure may be transmitted to the pressure detection unit 9 directly via the conductive shaft member 70 without passing through the pressure transmission member 8. In this case, an insulating member is interposed between the contact portion between the conductive elastic member 93 of the pressure detection unit 9 and the conductive shaft member 70. Note that if the conductive elastic member 93 is configured to have an electrode film on the surface facing the dielectric 91 of the non-conductive elastic member, it is not necessary to interpose an insulating member between the contact portion between the conductive elastic member 93 and the conductive shaft member 70. Furthermore, even if the pressure detection unit is made of a semiconductor device, or detects pressure as a change in inductance value or a change in resistance value, it is not necessary to provide an insulating member between the conductive shaft member 70 and the pressure detection unit.

[0109] In the above embodiment, the core holder is configured with a conductive shaft member 70, but the present invention is not limited to this embodiment, and the core holder 106 may be configured with a holder main body 1061 having a metal shaft configuration and a conductive elastic holding member 1062 as shown in Fig. 8. In this case, the insulating cap members 12, 12' may be disposed so as to cover the pen tip side of the core holder 106 so as to cover the conductive member 1062 of the core holder 106 in the example shown in Fig. 8.

[0110] Furthermore, the core body is not limited to the one configured to cover the center electrode with a protective member made of an insulating material, as in the core body 5 of the above embodiment. For example, the core body may consist of only the center electrode.

[0111] Furthermore, in the above-described embodiment, the cylindrical case portion 21 and the peripheral electrode 6 are made of conductive metal, but they may also be made of conductive resin. [Explanation of symbols]

[0112] 1...electronic pen, 2...casing (pen case), 3...main body unit, 4...battery, 5...core body, 6...peripheral electrode, 7...core body holder, 8...pressure transmission member, 9...pressure detection unit, 10...pressure transmission member storage unit, 11...insulating member, 12...insulating cap member, 21...cylindrical case portion, 22...sleeve portion, 31...unit holder, 34...circuit board, 51...center electrode, 52...protective member, 61...lead member, 70...conductive shaft member, 71...coil spring, 340...signal transmission circuit,

Claims

1. a housing configured by joining a cylindrical portion made of a conductive material and a sleeve portion made of a non-conductive material, the sleeve portion having a hollow portion communicating with the hollow portion of the cylindrical portion, in an axial direction with the sleeve portion facing the pen tip; a conductive core body disposed so that a tip portion thereof is exposed to the outside through an opening provided on the pen tip side of the housing; a peripheral electrode disposed in the hollow portion of the housing so as to surround the periphery of the core body; Equipped with the peripheral electrode includes an extension portion that extends across a joint between the cylindrical portion and the sleeve portion, from the hollow portion of the sleeve portion to the hollow portion of the cylindrical portion, An insulating member that electrically separates the peripheral electrode from the cylindrical portion is disposed in a space where the outer peripheral surface of the extension portion of the peripheral electrode faces the inner peripheral surface of the housing, with the inner peripheral surface of the insulating member abutting against the outer peripheral surface of the extension portion of the peripheral electrode and the outer peripheral surface of the insulating member abutting against the inner peripheral surface of the housing. An electronic pen characterized by:

2. The insulating member is disposed across the joint between the cylindrical portion and the sleeve portion in the axial direction, and has a portion located further rearward than the extension portion of the peripheral electrode.

2. The electronic pen according to claim 1 .

3. The insulating member is configured to hold the peripheral electrode.

2. The electronic pen according to claim 1 .

4. The peripheral electrode is disposed in a state where the outer peripheral surface of the portion excluding the extending portion in the axial direction is in contact with the inner wall surface of the sleeve portion.

2. The electronic pen according to claim 1 .

5. The extension portion of the peripheral electrode is thinner than the portion other than the extension portion.

5. The electronic pen according to claim 4.

6. a core holder having a fitting recess into which a rear end portion of the core body opposite to the front end portion is fitted, the core holder being electrically connected to the core body; The portion where the rear end of the core is fitted into the fitting recess of the core holder is disposed within the hollow space of the peripheral electrode, and is covered with a member for ensuring electrical insulation between the core holder and the peripheral electrode.

2. The electronic pen according to claim 1 .

7. The member for ensuring electrical insulation between the core holder and the peripheral electrode is configured as an insulating cap member configured to cover a predetermined length in the axial direction on the side of the core holder where the fitting recess is formed.

7. The electronic pen according to claim 6.

8. The core body comprises a center electrode made of a conductive material and a non-conductive member covering the center electrode in a state where the rear end side of the center electrode is exposed as the rear end portion of the core body.

7. The electronic pen according to claim 6.

9. the core body includes a center electrode made of a conductive material and a non-conductive member covering the center electrode in a state where the rear end side of the center electrode is exposed as the rear end portion of the core body, The member for ensuring electrical insulation between the core holder and the peripheral electrode is configured to cover the exposed rear end side of the center electrode of the core fitted in the fitting recess of the core holder.

7. The electronic pen according to claim 6.

10. a pressure detection unit that detects pressure applied to the tip of the core body is provided within the housing, The core holder is configured to transmit the pressure applied to the tip of the core directly or indirectly to the pressure detection unit.

2. The electronic pen according to claim 1 .

11. a pressure detection unit that detects pressure applied to the tip of the core body is provided within the housing, the core holder is configured to transmit a pressure applied to the tip of the core to the pressure detection unit via a pressure transmission member, The insulating member is configured to hold the peripheral electrode, and is attached to a member that houses the pressure transmitting member, which is axially connected to a pressure detecting unit holder that holds the pressure detecting unit.

11. The electronic pen according to claim 10.

12. The peripheral electrode is made of metal.

2. The electronic pen according to claim 1 .

13. a conductive wire for electrically connecting the peripheral electrode and a circuit board provided inside the housing; One end of the conductive wire is engaged between the rear end of the peripheral electrode and the insulating member, and the other end of the conductive wire is extended to the circuit board through the hollow space of the insulating member.

2. The electronic pen according to claim 1 .

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