WO2002093351A1

WO2002093351A1 - Writing instrument for writing discriminating system

Info

Publication number: WO2002093351A1
Application number: PCT/JP2002/004751
Authority: WO
Inventors: Tetsuo Yoshida; Takuji Sasada
Original assignee: Axiom Co., Ltd.
Priority date: 2001-05-16
Filing date: 2002-05-16
Publication date: 2002-11-21
Also published as: JPWO2002093351A1

Abstract

In a writing instrument having a vibrator in the core, variations in the state of the vibrator mounted on the core among individual are suppressed. A writing instrument (10) comprises a core (12) supported by an outer sleeve (16), and a pair of vibrators (20) disposed on the outer peripheral surface of the core (12) in opposed relation to each other with the center line (C) of the core (12) located therebetween. With such arrangement, since the plane of contact of the vibrators (20) with the core (12) is exposed outward, a more uniform adhesive agent layer can be formed when these are adhesively fixed, and variations in the mounted state of the vibrators (20) among individuals can be suppressed.

Description

Description Writing instrument for writing discrimination system Technical field

The present invention relates to a writing instrument for a writing discrimination system applicable to signature authentication and the like, and in particular, utilizes a vibrator provided in the writing core and utilizing the fact that the vibration of the writing core during writing is unique to the writer. Writing implement for performing writing discrimination. Background art

The applicant paid attention to the fact that the vibration of the writing lead differs for each writer when the writing implement was operated while the writing lead was vibrated by the vibrator, and conducted research and development on a writing discrimination system using this property. I have. So far, the applicant has filed a Japanese patent application, Japanese Patent Application No. 2000-42893, and Japanese Patent Application No. 2000-59526 with respect to this writing discrimination system. Here, with reference to the drawings, the configuration and operation of a writing instrument for this writing discrimination system will be described.

FIG. 9 shows an example in which the writing implement 70 is configured as a ballpoint pen. A cylindrical piezoelectric vibrator 74 is mounted on the rod-shaped brush lead 72 such that the brush lead 72 is inserted into a through hole of the piezoelectric vibrator 74. The piezoelectric vibrator 74 is fixed to the brush lead 72 by an adhesive uniformly and thinly applied to the inner surface of the through hole. The brush lead 72 is fixed to the outer cylinder 78 via an annular support fixture 76. With such a configuration, the piezoelectric vibrator 74 vibrates the brush lead 72 in the longitudinal direction by a voltage applied from the outside. The piezoelectric vibrator 74 is vibrated by a self-excited oscillation circuit (not shown), and the vibration of the piezoelectric vibrator 74 can be detected based on a signal of the self-excited oscillation circuit.

According to previous research, when writing with such a writing implement 70 and the writing lead 72 is vibrated, the pattern of vibration change of the writing lead 72 during writing depends on the writer. It turns out to be different. This is because the contact state (for example, pressing force, contact angle, etc.) between the writing core 72 and the writing medium (not shown) during writing and its change (for example, pen speed) have characteristics unique to the writer. It is thought to be. Therefore, Writing detection can be performed by detecting the vibration of the brush core 72 during excitation and comparing this with a unique vibration pattern registered in advance.

In the above-mentioned writing implement, the piezoelectric vibrator was fixed to the pen core with an adhesive applied to the inner surface of the through hole. However, in such a configuration, it is difficult to obtain a uniform adhesive layer due to bubbles contained in the adhesive layer, and the mounting state of the piezoelectric vibrator for each writing instrument (that is, the longitudinal direction of the brush core or Individual differences in the mounting position in the radial direction, or the mounting posture relative to the brush core, occurred, and this was the cause of the variation in the vibration characteristics (ie, resonance frequency, vibration mode, etc.) of each writing instrument. Disclosure of the invention

In a writing instrument for a writing discrimination system according to the present invention, a pair of a pen tip supported by a writing instrument main body and a vibrator provided on an outer peripheral surface of the pen tip so as to face each other with a center axis of the pen tip being interposed therebetween. , Are provided. According to such a configuration, the bonding surface of the vibrator with the brush core is exposed to the outside. For example, when these are bonded and fixed, a more uniform adhesive layer can be formed. Variations in the state of attachment of the vibrator to the brush lead can be suppressed as compared with the related art. Further, in the present invention, by providing a pair of vibrators so as to face each other with the center axis of the brush core interposed therebetween, bending vibration or abnormal oscillation due to asymmetric deformation of the brush core is suppressed. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view (partially sectional view) of a writing instrument for a writing discrimination system according to an embodiment of the present invention;

FIG. 2 is a perspective view showing a piezoelectric vibrator of a writing instrument for a writing discrimination system according to the first embodiment of the present invention,

FIG. 3 is an equivalent circuit diagram of a piezoelectric vibrator of a writing instrument for a writing discrimination system according to the first embodiment of the present invention,

FIG. 4 is a circuit diagram of a self-excited oscillation circuit incorporating a piezoelectric vibrator of a writing instrument for a writing discrimination system according to the first embodiment of the present invention,

FIG. 5 shows a piezoelectric vibrator of a writing instrument for a writing discrimination system according to the second embodiment of the present invention. Perspective view showing a moving element,

FIG. 6 is a perspective view showing a piezoelectric vibrator of a writing instrument for a writing discrimination system according to a third embodiment of the present invention,

FIG. 7 is an equivalent circuit diagram of a piezoelectric vibrator of a writing instrument for a writing discrimination system according to the third embodiment of the present invention,

FIG. 8 is a circuit diagram of a self-excited oscillation circuit incorporating a piezoelectric vibrator of a writing instrument for a writing discrimination system according to a third embodiment of the present invention,

FIG. 9 is a perspective view (partially sectional view) of a conventional writing instrument for a writing discrimination system. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a writing implement 10 according to the present embodiment, FIG. 2 is a perspective view of a piezoelectric vibrator 20 used in the writing implement 10, FIG. 3 is an equivalent circuit diagram of the piezoelectric vibrator 20, FIG. 4 is a circuit diagram of a self-excited oscillation circuit 30 that performs excitation and vibration detection of a brush lead.

In the present embodiment, the writing implement 10 is configured as a ballpoint pen. As shown in FIG. 1, a rod-shaped brush lead 12 (that is, an ink shaft) is fixed to a cylindrical outer cylinder 16 via an annular support fixture 14. The brush core 12 has one or more (one in the present embodiment) pairs of flat portions 12 at positions facing the center axis C of the brush core 12 on the outer peripheral surface thereof. A p-shaped piezoelectric vibrator 20 (20a, 20b) is fixed to the flat portion 12p by, for example, an adhesive. This piezoelectric vibrator 20 is incorporated in a self-excited oscillation circuit 30 (FIG. 4; described later), and vibrates the brush lead 12.

The piezoelectric vibrator 20 is provided so that the center thereof is located at a distance of 1/4 of the length of the brush lead 12 in the longitudinal direction from the end 12 a on the non-contact side of the brush lead 12. Further, the support fixture 14 is provided at a position spaced apart by 1/4 of the length of the brush lead 12 in the longitudinal direction from the end 12b on the contact side of the brush lead 12. When the piezoelectric vibrator 20 vibrates, the brush lead 12 vibrates most strongly in a standing wave vibration mode in which the length of the brush lead 12 is one wavelength. These installation positions (that is, positions separated from the longitudinal ends (12a, 12b) of the brush core 12 in the longitudinal direction by 1/4 of the length of the brush core 12, respectively) are In the section is there. In other words, since the brush core 12 is supported at the position of the node by the outer cylinder 16 as the writing implement body, it is necessary to suppress a change in vibration of the brush core 12 due to a stress change or deformation of the outer cylinder 16. Can be. Incidentally, in the above standing wave, both ends (12a, 12b) in the longitudinal direction and the center position in the longitudinal direction of the brush lead 12 are antinodes of vibration.

As shown in FIG. 2, the piezoelectric vibrator 20 includes a ceramic substrate 22 configured as a strip-shaped thin plate (a rectangular parallelepiped), and a pair of ceramic substrates 22 formed on the entire front and back surfaces of the ceramic substrate 22, respectively. (Positive electrode 24a, negative electrode 24b). A lead wire 26 is connected to the electrode (positive electrode) 24 a on the front side. In the present embodiment, the piezoelectric vibrator 20 can be manufactured more easily and with higher precision by making the piezoelectric vibrator 20 a flat plate. A DC voltage is applied to a pair of electrodes (24a, 24b) of the piezoelectric vibrator 20 under predetermined conditions, and the piezoelectric vibrator 20 is polarized. That is, the piezoelectric vibrator 20 is polarized in a direction perpendicular to the front surface and the back surface, and the polarization direction is from the front surface to the back surface or from the back surface to the front surface. As shown in FIG. 3, the piezoelectric vibrator 20 having been subjected to the above polarization treatment has an inductance component L, a capacitance component C, and a resistance component between the positive electrode 24a and the negative electrode 24b. This is equivalent to a circuit having R in series and further having a braking capacity component C d in parallel with them.

The paired piezoelectric vibrators 20 are desirably provided on the outer peripheral wall of the brush lead 12 so as to vibrate while deforming in a shape symmetrical with respect to the central axis C. In this way, the brush lead 12 itself vibrates while deforming into a shape symmetrical with respect to the central axis C. If only one piezoelectric vibrator is provided on the outer peripheral wall of the brush core, the brush core expands and contracts (vibrates) around the position where the piezoelectric vibrator is provided, so that bending vibration or abnormal oscillation is likely to occur. On the other hand, by providing the outer peripheral wall of the brush lead 12 so as to vibrate while deforming in a shape symmetrical with respect to the center axis C, bending vibration and abnormal Oscillation and the like can be suppressed, and loss of driving energy of the piezoelectric vibrator 20 can be reduced. In order to obtain such vibrations, in the present embodiment, as shown in FIG. 1, each of the plane portions 12 p formed in parallel and forming a pair has a piezoelectric vibrator (20 a, 2 O b). Negative electrode (electrode to which negative voltage was applied during polarization) 24 b is joined. As a result, the polarization directions of the paired piezoelectric vibrators 20 are all directed from the radially inner side to the outer side of the brush lead 12, and they are symmetric with respect to each other with the center axis C of the brush lead 12 interposed therebetween. Become. Further, these pairs of piezoelectric vibrators 20 are provided electrically in parallel. Specifically, as shown in FIG. 4, the electrodes (that is, the negative electrodes) 24 b on the plane portion 12 p side are connected to each other, and the positive electrodes 24 a on the opposite side are connected. Here, the piezoelectric vibrator 20 expands and contracts in the polarization direction according to the applied voltage. Piezoelectric vibrators thus provided and connected in parallel

The pair 20 vibrates while being deformed into a shape symmetrical about the central axis C of the brush lead 12. Although the piezoelectric vibrator 20 expands and contracts in the longitudinal direction according to the Poisson's ratio, the piezoelectric vibrator 20 is long in the longitudinal direction of the brush core 12, so that the brush core 12 mainly has the longitudinal direction. Longitudinal vibration occurs.

In this embodiment, at least a part of the surface of the outer wall 12 w (at least the plane portion 12 p) of the brush core 12 as an ink axis is configured as a conductor (for example, an aluminum alloy or the like), and a pair of piezoelectric vibrations It is in communication with the electrode (here, the negative electrode) 24 b on the brush core 12 of the child 20. With such a configuration, it is possible to more easily apply a voltage to the electrode 24 b on the side of the brush core 12 that is not exposed in contact with the brush core 12 via the conductor of the brush core 12.

As shown in FIG. 4, the self-excited oscillation circuit 30 according to the present embodiment includes an amplification circuit 32, a pair of piezoelectric vibrators 20 (20a, 2Ob), and a filter circuit 34. Are connected in series in this order. Among them, the filter circuit 34 has an action of suppressing the influence of unnecessary vibration (spurious) of the piezoelectric vibrator 20. The center frequency is substantially equal to the center frequency of the piezoelectric vibrator 20. The positive electrode 24 a of the piezoelectric vibrator 20 is connected to the input terminal of the filter circuit 34, and the negative electrode 24 b of the piezoelectric vibrator 20 is an amplifier circuit

32 Each output terminal is connected. The output terminal of the filter circuit 34 is connected to the conductor (outer wall 12 w) of the brush core 12 described above. This conductor is connected to the output terminal of the amplifier circuit 32 and the piezoelectric vibrator 2. It will be interposed between the negative electrode 24 b of 0. In such a configuration, a change over time in the frequency of the writing lead 12 during writing is detected as a change over time in the frequency of the signal of the self-excited oscillation circuit 30, and the detected data is registered in advance. By comparing with the registered data of the change over time of the frequency for each writer and each written (for example, signature), the written judgment can be performed.

Next, a second embodiment of the present invention will be described with reference to the drawings. The writing instrument according to the present embodiment is different from the writing instrument according to the first embodiment in that a piezoelectric vibrator 40 is provided instead of the piezoelectric vibrator 20. It has the same configuration as the first embodiment. For this reason, here, the piezoelectric vibrator 40 according to the present embodiment will be described, and detailed description of the other components will be omitted. FIG. 5 is a perspective view of the piezoelectric vibrator 40.

As shown in FIG. 5, the piezoelectric vibrator 40 includes a ceramic substrate 42 configured as a strip-shaped thin plate (a rectangular parallelepiped), and a pair of electrodes 4 respectively formed on the front and back surfaces of the ceramic substrate 42. 4 (positive electrode 44a, negative electrode 44b). In the present embodiment, a conductor film 44 c communicating with the electrode 44 b on the back surface is formed on the side surface and the front surface of the ceramic substrate 42. The piezoelectric vibrator 40 is closely fixed to the brush lead 12 such that the back surface and the outer peripheral surface of the brush lead 12 are in contact with each other. A voltage can be more easily applied to the electrode (here, the negative electrode 44 b) on the side of the brush core 12 that is not exposed in contact with the brush core 12. For this reason, it is not necessary to provide a conductor portion on the brush lead 12. On the front surface side, the positive electrode 44a and the conductor film 44c are insulated by the separation band 44d in which the thin film of the metal conductor is not formed on the surface. At this time, it is desirable that the area of the positive electrode 44a be larger than the area of the conductive film 44c. As the area of the positive electrode 44a is larger, the piezoelectric vibrator 40 is deformed in a wider area, so that bending vibration and abnormal oscillation are suppressed. A lead wire 46a is connected to the positive electrode 44a, and a lead wire 46b is connected to the conductor film 44c. The negative electrode 44b is formed on the entire back surface. This piezoelectric vibrator 40 is also subjected to polarization processing in the same manner as in the above embodiment.

Next, a third embodiment of the present invention will be described with reference to the drawings. In the present embodiment, the piezoelectric vibrator 50 is a three-terminal type, and accordingly, the self-excited oscillation circuit 60 has a different configuration from the self-excited oscillation circuit 30 according to the first and second embodiments. However, other configurations are the same as those in the first and second embodiments. For this reason, here, the piezoelectric vibrator 50 and the self-excited oscillation circuit 60 according to the present embodiment will be described, and detailed description of other configurations will be omitted. 6 is a perspective view of the piezoelectric vibrator 50, FIG. 7 is an equivalent circuit diagram of the piezoelectric vibrator 50, and FIG. 8 is a circuit diagram of the self-excited oscillation circuit 60.

As shown in FIG. 6, the piezoelectric vibrator 50 includes a ceramic substrate 52 configured as a strip-shaped thin plate (a rectangular parallelepiped). The surface of the ceramic substrate 52 has two electrodes ( A first electrode [drive electrode] 54a and a third electrode [return electrode] 54c) are formed, and one electrode (second electrode [ground electrode] 54b) is formed on the back surface. Further, on the side and front surfaces of the ceramic substrate 52, a conductive film 54d that is electrically connected to the back electrode (second electrode 54b) is formed. On the front side, the first electrode 54a, the third electrode 54c, and the conductor film 54d are arranged in this order, and the gap between them is insulated by the separators 54e, 54f, respectively. ing. At this time, the area of the first electrode 54a is preferably larger than the total area of the third electrode 54c and the conductor film 54d for the same reason as in the second embodiment. Lead wires (56a, 56b, 56c) are connected to the first, third and conductor films (54a, 54c, 54d), respectively. A second electrode 54b is formed on the entire back surface. The piezoelectric vibrator 50 having such a configuration is fixed to the brush lead 12 so that the back surface and the outer peripheral surface of the brush lead 12 are in contact with each other, instead of the piezoelectric vibrator 20 of FIG. As shown in FIG. 7, the piezoelectric vibrator 50 that has been subjected to the above-described polarization treatment has an inductance component L and a capacitance component C between the first electrode 54a and the third electrode 54c. And a resistance component R in series, a braking capacitance component C d 1 between the first electrode 54 a and the second electrode 54 b, and a second electrode 54 b and a third electrode 54 This is equivalent to a circuit having a braking capacity component C d 2 between the circuit and the circuit c.

As shown in FIG. 8, the self-excited oscillation circuit 60 according to the present embodiment is configured by connecting an amplifier circuit 32, a pair of piezoelectric vibrators 50, and a filter circuit 34 in series in this order. Is done. In this case, the first electrode 54a is connected to the input terminal of the filter circuit 34, the third electrode 54c is connected to the output terminal of the amplifier circuit 32, and the second electrode 54b is connected to the ground. It is connected it. Industrial applicability

As described above, the writing implement according to the present invention can suppress variations in the mounting state of the vibrator with respect to the brush lead, and can suppress bending vibration or abnormal oscillation due to unbalanced deformation of the brush lead. can do. Therefore, it is suitable for use in a handwriting discrimination system for performing signature authentication.

Claims

The scope of the claims

1. A brush core supported by the writing instrument body,

A writing instrument for a writing discrimination system, comprising: a pair of vibrators provided on the outer peripheral surface of the brush core so as to face each other across the central axis of the brush core.

2. A pair of planes is formed on the outer peripheral surface of the brush lead so as to face each other with the central axis of

2. The writing instrument for a writing discrimination system according to claim 1, wherein the vibrator is formed in a flat plate shape and is fixed on the flat surface.

3. The vibrator pair includes a plate-shaped substrate, and is polarized by electrode pairs formed on both front and back surfaces of the substrate.

2. The writing implement for a writing discrimination system according to claim 1, wherein the pair of transducers are provided such that each polarization direction is symmetric with respect to a central axis of the writing core.

4. The vibrator includes a plate-shaped substrate, is polarized by electrode pairs formed on both front and back surfaces of the substrate, and is attached to the brush lead so that the back surface of the substrate comes into contact with the brush lead outer peripheral surface. Fixed,

On the side and / or the surface of the substrate, writing determination system for a writing instrument according to claim 1, wherein a conductive film electrically connected to the back electrode are made form ₍