JP2001142624A - Device for inputting coordinates - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinates input device which is very light, also small and foldable. SOLUTION: An electronic blackboard 1 is provided with an oscillation coil generating an alternating field of a prescribed frequency, a pen 60 provided with marker ink, a nonconductive cloth made writing part 21, and a receiving part 10 which is constructed on the part 21 and has the pen 60 and a loop coil 23 composed of a plurality of magnetically connectable SUS lines arranged vertically and horizontally, and can read the coordinates of the track of the pen 60 drawn on a flip chart, etc., on the part 21 with the part 10 to electronically record the coordinates. When the blackboard is not used, the blackboard can be housed and carried by removing the upper and lower supporting poles 45 and 46 and folding the cloth made writing surface 21 into a small size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a coordinate input device provided with a foldable cloth receiver.

[0002]

2. Description of the Related Art For example, a pen-shaped transmitting section provided with an oscillation coil for generating an alternating magnetic field of a predetermined frequency, and a writing surface such as a whiteboard or a flip chart are provided. And a receiving unit on which a plurality of loop coils are laid.The coordinates of the trajectory of the pen drawn on the writing surface are read based on an induced voltage induced in the loop coil of the receiving unit, and this is electronically read. Coordinate input devices such as electronic blackboards for recording are proposed. With such an electronic blackboard, characters and figures drawn on a whiteboard or a flip chart can be read electronically without having to copy and copy each time with a copying device.

[0003]

However, the conventional electronic blackboard is provided with a white board or a hard panel as an underlay of the flip chart, and is large and heavy, and cannot be folded. For this reason, a dedicated floor stand was used to support the electronic blackboard, or the electronic blackboard was fixed to a wall with metal fittings. It is possible to move such an electronic blackboard by using a caster or the like attached to the floor stand, but there is a problem that it is not easy to move to an outside place. On the other hand, because it has a large writing surface, there is a problem that a large space is required to store the electronic blackboard when not in use, and the writing surface occupying a large area lacks decorativeness, Leaving it in that position not only occupies a large space, but also detracts from the aesthetics of the room. Also, JP-A-10-3
There has been proposed an electronic blackboard device sheet described in Japanese Patent No. 29491, an electronic blackboard having a rollable writing surface, such as an electronic blackboard described in Japanese Patent Application Laid-Open No. 11-8724. However, even if the sheet itself can be wound up, the device that reads characters and graphics from this sheet is larger and heavier than the sheet width,
These also have a problem that they cannot be easily moved or stored.

An object of the present invention is to provide a coordinate input device which is extremely light and can be folded small.

[0005]

In order to achieve this object, a coordinate input device according to the first aspect of the present invention comprises a transmitting unit having an oscillation coil for generating an alternating magnetic field of a predetermined frequency, and an insulator. A writing unit having a cloth base material, a loop coil formed of a plurality of conductive thread members capable of being magnetically coupled to the alternating magnetic field laid on the base material, and a transmission unit drawn on the writing unit And a receiving unit that reads and outputs the coordinates of the trajectory.

In the coordinate input device according to this configuration, when used as a coordinate input device, an alternating magnetic field of a predetermined frequency is generated by a transmission unit having an oscillation coil, and a plurality of magnetic fields are laid on a cloth base material as an insulator. A writing unit having a loop coil made of a conductive thread-shaped member is magnetically coupled to the alternating magnetic field, and reads and outputs the coordinates of the trajectory of the transmission unit drawn on the writing unit from the voltage induced in the loop coil. When not in use, the substrate is made of cloth, and the loop coil is also made of a conductive thread-like member, so it is extremely light,
In addition, it is small and can be folded, so that storage, transportation and the like become extremely easy.

In the coordinate input device according to the second aspect of the present invention,
In addition to the configuration of the coordinate input device according to the first aspect, the loop coil is formed of an uncoated conductive yarn.

[0008] In the coordinate input device according to this configuration, since the loop coil is formed of an uncoated conductive yarn, flexibility can be increased as compared with a device using a coated loop coil.

According to a third aspect of the present invention, there is provided a coordinate input device.
In addition to the configuration of the coordinate input device according to the second aspect, the loop coil is a stainless steel thread formed in a fibrous shape having flexibility.

[0010] In the coordinate input device according to this configuration, since the loop coil is made of stainless steel, electric resistance can be reduced, and reception with a good S / N ratio can be performed. In addition, since it is formed into a fibrous shape and has flexibility, even if it is laid on the substrate, the flexibility of the substrate is not impaired.

[0011] In the coordinate input device of the invention according to claim 4,
In addition to the configuration of the coordinate input device according to any one of claims 1 to 3, the loop coil is sewn and laid on the base material by a lockstitch sewing machine.

In the coordinate input device according to this configuration, since the loop coil is sewn to the cloth base material by the lockstitch sewing machine, the loop coil can be laid easily and efficiently.
Further, the laid loop coil can be firmly fixed to the base material.

[0013] In the coordinate input device according to the fifth aspect of the present invention,
In addition to the configuration of the coordinate input device according to claim 4, wherein the loop coil is a lower thread, an insulator thread is an upper thread, and the thread tension is adjusted by the lockstitch sewing machine to serve as a lower thread. Are sewn and fixed so as to be exposed only on one surface of the base material.

In the coordinate input device according to this configuration, since the sewing is performed so as to be exposed only on one surface side of the base material only by adjusting the thread tension with the lockstitch sewing machine, the loop coil can be easily insulated.

[0015] In the coordinate input device of the invention according to claim 6,
In addition to the configuration of the coordinate input device according to claim 5, on the one surface side of the base material, a plurality of loop coils are arranged in parallel so as to overlap adjacent loop coils by a fixed width. When the loop coil is laid, after laying a part of the loop coil,
At the longitudinal end of the loop coil, the base material is folded back by a predetermined width so as to cover the end of the already laid loop coil, and the longitudinal end of the next laid loop coil is The base material is laid so as to come to an end portion of the base material folded back by a predetermined width.

In the coordinate input device according to this configuration, a plurality of loop coils are arranged in parallel so as to overlap with adjacent loop coils by a fixed width while maintaining insulation between the loop coils with one cloth base material. can do. Further, it is possible to lay another set of loop coils with a phase of 90 ° on the back surface of the base material on which one set of loop coils is laid.

According to a seventh aspect of the present invention, there is provided a coordinate input device.
In addition to the configuration of the coordinate input device according to any one of claims 1 to 3, the loop coil is penetrated through the base material at predetermined intervals, and is exposed and fixed alternately on the front and back sides. And

In the coordinate input device according to this configuration, a loop coil can be laid even in a place where a lockstitch sewing machine or the like cannot be used or a material of the loop coil that is not suitable for the sewing machine, even by hand sewing.

In the coordinate input device of the invention according to claim 8,
In addition to the configuration of the coordinate input device according to any one of the first to third aspects, the loop coil is fixed to a loop coil fixing means fixedly penetrating the base material.

In the coordinate input device according to this configuration, even if the material of the loop coil is difficult to be sewn to the base material, the wire can be securely laid in a so-called wire bonding manner.

According to a ninth aspect of the present invention, there is provided a coordinate input device.
In addition to the configuration of the coordinate input device according to claim 8, the loop coil fixing means is made of a conductor, and simultaneously fixes the loop coils on both surfaces of the base material, and short-circuits the fixed loop coils. It is characterized by the following.

In the coordinate input device according to this configuration, the loop coils can be reliably short-circuited at a concentrating portion where the short-circuit between the loop coils is required. Further, the loop coil can be securely fixed.

According to a tenth aspect of the present invention, in addition to the configuration of the coordinate input device according to any one of the first to third aspects, the loop coil includes one of the base members.
On the surface side, it is fixed so as to be pressed down by a thread made of an insulator sewn with a zigzag sewing machine.

In the coordinate input device according to this configuration, even when sewing with a lockstitch sewing machine or the like is difficult, the coordinate input device can be firmly fixed to one surface side of the base material.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A graphic input device according to the present invention will be described below with reference to the accompanying drawings, taking an electronic blackboard 1 as a preferred embodiment as an example. FIG. 2 is an external view illustrating a main configuration of the electronic blackboard 1. As shown in the drawing, the electronic blackboard 1 of the present embodiment includes a pen 60 as a transmitting unit, a writing unit 21, and a receiving unit 10 including an operation unit 30 attached to a lower part of the writing unit 21. , A personal computer (hereinafter abbreviated as PC) 10 connected to the operation unit 30.
0, a printer 200.

First, the main configuration of the pen 60, which is a transmitting unit, will be described with reference to FIG. FIG. 3 is an explanatory diagram showing the internal structure of the pen 60, and FIG.
FIG. 4 is an explanatory diagram illustrating an electrical configuration of a zero.

As shown in FIG. 3, the pen 60 is provided with a cylindrical body 61a and a lid 61c detachably attached to the rear end of the body 61a. Body part 6
1a, a coil L1, an ink cartridge 63 that can be taken out in a direction indicated by an arrow F2, a pen tip 62 inserted into the ink cartridge 63, and a coil L
A circuit board 69 on which an oscillation circuit or the like for generating an alternating magnetic field is mounted from 1, and a battery 70 as a power supply for supplying electricity to the circuit board 69 are provided. This coil L1 has an inner diameter of about 15 mm and a length of about 15 mm.
It is wound 00 times to form a ring. In addition, the writing surface 21
a (see FIG. 1) is arranged at a distance of about 20 mm from the tip of the pen tip 62 that contacts the pen tip 62.

Between the ink cartridge 63 and the circuit board 69, there is provided a push-button switch 67 for supplying and shutting off electricity to the circuit board 69 and the like. The switch 67 connects the pen tip 62 to the writing surface 21.
a (see FIG. 1), the ink cartridge 63 is turned on when the ink cartridge 63 moves in the direction indicated by the arrow F1, and when writing is stopped, the ink cartridge 63 returns to the direction indicated by the arrow F2 by a spring in the switch 67 and turns off. That is, the writing surface 2 is
An alternating magnetic field is generated from the coil L1 only when writing on 1a.

As shown in FIG. 8, the circuit mounted on the circuit board 69 (see FIG. 3) is used for the pen 60 (see FIG. 3) such as the color of the ink and the thickness of the pen tip 62 (see FIG. 3). A CR oscillation circuit 69e in which a different modulation frequency fm is set for each attribute (hereinafter referred to as a pen attribute);
An LC oscillation circuit 69c that oscillates a carrier wave that carries a signal oscillated from the oscillating circuit.
(Frequency Shift Keying) and an FSK circuit 69d for performing modulation. The oscillation frequency of the carrier is determined by the coil which is the inductance L1 and the capacitors C2 and C3 which are the capacitances of the LC oscillation circuit 69c.
It is determined by the capacitor C5, the resistor R2, and the variable resistor R3, which constitute the CR oscillation circuit 69e. The frequency shift of the carrier oscillation frequency is F
Capacitor C4, which is the capacitance of SK circuit 69d
Is determined by the capacity of

The relationship between the pen attribute and the modulation frequency fm is set as shown in FIG. 10A for explaining the relationship. In FIG. 10A, “thin” means the pen tip 62
(See FIG. 3) indicates that the pen is thin, and “thick” indicates that the pen tip 62 is thick. For example, “black thick” indicates a pen whose pen tip 62 is thick and uses black ink.

In FIG. 8, when the switch 67 is turned on, electricity of the battery 70 is supplied to each circuit, and the output of the integrated circuit IC3 of the CR oscillation circuit 69e is output to the MSK of the FSK circuit 69d.
The gate of the OSFET is switched, and the LC oscillation circuit 6
The carrier wave oscillated from 9c is frequency-modulated by the signal oscillated from the CR oscillation circuit 69e. In the present embodiment, the center frequency of the carrier is 410 kHz, and the frequency shift is ± 15 kHz. In the present embodiment, the integrated circuit IC1 is a TC7SLU04F manufactured by Toshiba, and the integrated circuits IC2 and IC3 are both TC7SLU manufactured by Toshiba.
LU04. The MOS FET is 2SK215
8 The resistors R1 and R2 are both 1 MΩ, and the variable range of the variable resistor R3 is 0Ω to 1MΩ. Capacitors C2, C3, C4 and C5 are 2700 pF and 1 respectively.
000 pF, 270 pF, and 100 pF. further,
Battery 70 is LR44, and its voltage is about 1.5V.

Next, the configuration of the receiving unit 10 of the electronic whiteboard 1 according to the present embodiment will be described with reference to FIGS. FIG. 1 is a diagram illustrating a configuration of the receiving unit 10 of the electronic whiteboard 1. The receiving unit 10 includes a writing unit 21 and an operation unit 30.

As shown in FIG. 1, the writing section 21 is formed by laminating a flexible cloth or the like having a rectangular shape that is slightly longer in the vertical direction, and is provided with a loop coil 23 laid inside. The writing surface 21a on the front surface (the front side in FIG. 1) of the writing unit 21 is a portion to be an underlay when writing with the pen 60 on the flip chart FC (see FIG. 2). Here, the flip chart FC is obtained by temporarily fixing the upper ends of a plurality of writing papers as shown in FIG. 2 and bundling them in a tear-off manner. Here, the top page FC1 and the second page FC2 are used. The third page FC3 is hooked on hooks 48 in a stacked state. Then, when the pen 60 presses the pen tip 62 (see FIG. 3) with the pen 60 on the top page FC1, ink is supplied from the ink cartridge 63, and characters and figures are written on the flip chart FC. Here, the content written by the pen 60 is recognized by the receiving unit 10, and its coordinates and pen attributes are input. When there is no more space to write to the first page FC1, the first page FC1 is manually removed, the second page FC2 is exposed, and the page feed button is pressed down, and the next page is displayed on the control unit 3. The next writing is started after notifying that it has shifted to the record of. If the user wants to correct the previous page, the removed first page FC1 is hooked on the hooks 48, 48 and returned, and the page return button 33 is pressed, so that the control unit is informed that the previous page has been returned. After the notification, the removed first page FC1 is corrected.

The periphery of the writing portion 21 is folded back and its ends are sewn to form a bag. The bag portion 41 at the upper end, the bag portion 42 at the lower end, the bag portion 43 at the left end, and the bag portion 43 at the right end. A bag portion 44 is formed. Then, the upper support bar 45 is horizontally penetrated and disposed inside the bag portion 41 at the upper end.
Here, FIG. 24A is a perspective view showing a state where the upper support bar 45 is extended. FIG. 24B is a perspective view showing a state where the upper support bar 45 is stored.

As shown in FIG. 24A, the upper support rod 45 is entirely divided into three parts, a first slide part 45d, a base part 45e, and a second slide part 45f, each of which is made of a hard non-magnetic metal. Alternatively, it is an elongated rod-shaped member made of resin and having a U-shaped cross section opened downward in a cross section perpendicular to the longitudinal direction. The base portion 45e is the thickest, the first slide portion 45d is the second, and the thinnest is the second slide portion 45f. Therefore, the first sliding portion 45d
Can be housed inside the base 45e, and the second slide part 45f can be housed inside the first slide part 45d.

At both ends of the base 45e, a writing surface fixing hole 45g for inserting a writing surface fixing screw 45h in the front-rear direction is provided.
45g are drilled. The writing surface fixing screw 45h on the left side of the base 45e passes through the following portions in the following order and is screwed into the hook 48. That is, the washer 45i and the bag 41
The rear screw hole 41a, the writing surface fixing hole 45g on the rear side of the base 45e, the rear hole (not shown) of the first slide portion 45d, the front hole (not shown) of the first slide portion 45d, and the front side of the base 45e. The portion shown here is pierced in the order of the writing surface fixing hole 45g and the front screw hole 41a of the bag portion 41. Accordingly, the first slide portion 45d is fixed to the base 45e, and the upper support bar 45 itself is fixed to the bag portion 41.
Similarly, the writing surface fixing screw 45h on the right side of the base 45e is also
Similarly, the second slide portion 45f is fixed to the base portion 45e, and the upper support bar 45 itself is fixed to the bag portion 41. Since the upper support bar 45 is attached in this manner, the writing section 2 is used to evenly support the entire writing section 21 in the bag section 41.
1 can be supported while maintaining high flatness without causing unnecessary wrinkles or the like. Also, flip chart FC
Can also support the flip chart FC in a stable posture.

Both ends of the upper support bar 45 are exposed from the bag 41, and fixing holes 45a, 45a are respectively formed. As shown on the left side of FIG. 1, a hanging bracket 47 can be attached to the fixing holes 45a, 45a by a fixing screw 45b, and the hanging bracket 47 is horizontally disposed as shown by a two-dot chain line, for example. To the horizontal bar HB or the like. Also, as shown on the right side of FIG.
The fixing hole may be directly screwed to a wall surface or the like without mounting the hanging bracket 47.

A lower support bar 46 having the same configuration as the upper support bar 45 is provided at the lower end of the bag 42 below the writing unit 21. However, a writing surface fixing screw (not shown) penetrates a portion similar to the upper support rod 45, but penetrates the bag portion 42 instead of the bag portion 41, and also passes through the fixing hole 49a of the connector 49 instead of the hook 48. It is screwed.

The lower supporting rod 46 is, together with the upper supporting rod 45, a cloth writing section 2 suspended horizontally by the upper supporting rod 45.
1 is applied with a tension in the vertical direction to prevent wrinkles from occurring and to enhance the flatness. Although the lower support bar 46 itself has a weight and applies a certain amount of tension to the writing unit 21, when the operation unit 30 is connected to the lower support bar 46 as shown in FIG. Tension is applied to the writing unit 21 via the support bar 46 to improve the flatness of the writing unit 21. Further, if a screw is inserted into fixing holes 46a, 46a formed at both ends of the lower support rod 46 and screwed to a wall or the like, an extremely large tension is applied to the writing portion 21 and the writing portion 21 is tightly fixed to the wall. Can be done. The bag 43 at the left end and the bag 44 at the right end between the upper support bar 45 and the lower support bar 46 are made of a rigid member, a member provided with a biasing means such as a spring, or an elastic body. Arrange members etc.,
If the writing unit 21 is tensioned by being fixed or urged in a direction in which the upper support bar 45 and the lower support bar 46 are separated from each other, the writing unit 21
It can be used on its own. Since the writing section 21 itself is configured to be extremely lightweight, the writing section 21 may be attached to a wall surface or the like by attaching a planar fastener to the back surface. Writing section 2 especially for easel for flip chart
If a clip or a sheet fastener for fixing the fastener 1 is provided, the easel can be used like an electronic blackboard.

The upper support bar 45 and the lower support bar 46 are configured to be detachable.
By pulling out 6, the writing unit 21 can be folded extremely compactly. In particular, as shown in FIG.
By removing the writing surface fixing screw 45h from the upper support bar 45 in the state shown in FIG. 24 (A), it is possible to pull out the writing portion 21 from the bag portion 41, and further, inside the bag portion 41, the base portion 45e. When the first slide portion 45d is inserted into the first slide portion 45d and the second slide portion is further inserted into the first slide portion 45d, the overall length of the upper support rod 45 is shortened, and
The writing unit 21 can be folded while the writing unit 21 is kept in the storage unit 1.
Similarly, since the lower support bar 46 can be shortened while being stored in the bag portion 42, the writing portion 21 can be folded small.

The structure of the upper support bar 45 and the lower support bar 46 is not limited to the example shown here, but may be a structure like a rod antenna, or may be folded and folded, or joined. In short, any structure may be used as long as the writing portion 21 can be supported during use and can be folded compactly when not in use.

The electronic blackboard 1 can be used in a horizontal position. That is, the upper support bar 45 inserted into the upper bag portion 41 is inserted into the left bag portion 43. At this time, the interval D1 between the hooks 48, 48 shown in FIG. 1 and the interval D1 between the screw holes 43a, 43a are provided so as to have the same width, so that the screw holes 43a, 4 provided here are provided.
Using hooks 48, 48 in the same manner as described above using 3a
And so on. Similarly, the lower support bar 46 inserted in the bag portion 42 is inserted and fixed in the bag portion 44 at the right end. In this case, the bag portion 43 can be used as the upper side. In this case, the operation unit 30 is connected to the connector 49.
If it is fixed to, the balance will be lost due to its weight,
If the operation unit 30 is moved to the bag unit 44 side and fixed, and once connected to the connector 49 via an extension cable, the operation unit 30 can be used as a weight and can be used stably.

A connector 49 is provided at the center of the lower support rod 46.
Is arranged. The connector 49 is a connector for connecting the operation unit 30 as shown in FIG. The loop coil 23 laid inside has a connector 4
9 is connected at its end by concentrating.

As shown in FIG. 2, the operating section 30 is attached to the connector 49 below the writing section 21. Operation unit 30
Is substantially box-shaped, and has a structure in which operation parts are provided in a concentrated manner on the front surface thereof and can be connected to the connector 49 above. Each circuit of the control unit 3 shown in FIG. 9 is mounted inside the operation unit 30. The operation unit 30 has a speaker 31 for reproducing sounds such as an operation sound and a warning sound, and a seven-segment page number in which data indicating the content written on the writing surface 21a (hereinafter abbreviated as writing data) is stored. A page number display LED 32 displayed by an LED, a page return button 33 for returning one page each time the button is pressed, a page forward button 34 for forwarding one page each time the button is pressed, and one page each time the stored writing data is pressed. Delete button 3
5, a printer output button 36 pressed to output the stored writing data to the printer 200 (FIG. 2);
A PC output button 37 pressed to output the stored writing data to the PC 100 (FIG. 2), an input warning LED 39a for warning of an input failure, a battery warning LED 39b for warning of battery exhaustion, and the electronic whiteboard 1 A power button 38 is provided for pressing to activate.

The electronic blackboard 1 is located at the lower front of the operation unit 30.
A battery case 14 is provided for accommodating four C-size batteries as a power source, and a lid that can be opened and closed is attached. On the right side of the battery case 14, the speaker 3
One volume control knob 13c is provided, and connectors 13b and 13a are provided on the right side thereof. The plug 13 of the connection cable 204 connected to the printer 200 is connected to the connector 13b, and the connection cable 1 connected to the PC 100 is connected to the connector 13a.
04 plug 102 is connected. In other words, electronic blackboard 1
The writing data indicating the contents written on the writing surface 21a of P
Monitor 10 output to C100 and provided in PC 100
3, the content written on the electronic whiteboard 1 can be viewed. Further, it is also possible to output handwriting data to the printer 200 and print the contents handwritten on the electronic blackboard 1 on the printing paper 203. Of course, the printer 200
May be connected. It is desirable to use a USB cable for these cables because power can be supplied at the same time and the connector plug itself can be reduced in size.

Further, the PC 100 itself may be configured to be suspended and supported below the writing unit 21 together with the operation unit 30. In this case, the PC 100 itself is used as a weight and contributes to maintaining the flatness of the writing unit 21.

In the present embodiment, the height H of the writing surface 21a
1 is 900 mm, and the width W1 is 600 mm. In addition, the writing portion 21 is made of a woven or non-woven fabric made of synthetic fibers such as polyester and polyamide fibers, as described below.
The writing unit 21 itself is formed of a thin metal sheet or the like and is lightweight and flexible, and the weight of the writing unit 21 itself is approximately 500 g or less.

Next, the structure of the writing unit 21 will be described with reference to FIG. FIG. 4 is an explanatory diagram showing each component of the writing unit 21. The writing unit 21 includes a protective sheet 27 constituting the writing surface 21a, a base material 22 on which the loop coil 23 is laid, a magnetic shield sheet 24, an electric shield sheet 25, and a decorative thin cloth 26 laminated in this order. Structure. In this embodiment, the protective sheet 27 is formed to a thickness of about 0.1 mm by a polyester film, and the substrate sheet 22 is formed to a thickness of about 0.4 mm by a nonwoven fabric such as polyester. Is formed.
Further, the magnetic shield sheet 24 is formed to a thickness of 50 μm together with a polymer film by Finemet (registered trademark) manufactured by Hitachi Metals, Ltd., and the electric shield sheet 25 is formed of aluminum.
4 is formed to a thickness of 25 μm on the back surface and is electrically grounded. The thickness of the entire writing section is approximately 1 mm.

The magnetic shield sheet 24, the electric shield sheet 25, the decorative thin cloth 26 and the protective sheet 2
Reference numeral 7 is not an essential configuration, and the writing surface 21 can be configured without these components only with the base material 22 and the loop coil 23. However, if the magnetic shield sheet 24 and the electric shield sheet 25 are provided, the magnetic shield sheet 24 and the electric shield sheet 25 can be used in close contact with a metal surface, and can be used regardless of the use place. When the decorative thin cloth 26 is not used, the back side on which the decorative thin cloth 26 is arranged can be used as an interior decoration like a tapestry if the back surface on which the decorative thin cloth 26 is arranged is turned upside down, and a place for storage is secured. Easy to do. The protection sheet 27 can not only ensure insulation of the loop coil 23 but also can be used like a white board if the surface is made of a water-repellent white sheet.

Next, the configuration of the loop coil 23 will be described with reference to FIG. FIG. 5A is an explanatory view showing a part of the configuration of the loop coil 23 shown in FIG. 4, and FIG. 5B is a diagram showing the loop coil 23 shown in FIG.
It is explanatory drawing which shows the width | variety and overlap pitch. In the following description, of the loop coils 23, a loop coil arranged in the X-axis direction is called an X coil, and a loop coil arranged in the Y-axis direction is called a Y coil. As shown in FIG. 5A, the X-axis of the (X, Y) coordinate of the pen 60 is set in the X-axis direction.
There are m X coils X1 to Xm for detecting coordinates, and Y coils for detecting Y coordinates are arranged in the Y-axis direction.
N coils 1 to Yn are arranged orthogonally to the X coil. The X coil and the Y coil are each formed in a substantially rectangular shape, and the length of the long side of the rectangular portion is P
2Y and P2X.

As shown in FIG. 5B, the length of the short side of the rectangular portion of the X coil is formed to have a width P1, and the adjacent X coil has a width slightly less than half of the width P1. They are superimposed on the pitch. Each Y coil has width P1
, And the adjacent Y coils are overlapped at a pitch slightly less than half the width P1. Also, X1, X2,... Xm of one of the terminals of the X coil
And an X ground electrode GX in which terminals on the ground side of each coil are combined.
X connector CNX. And connector 4
9 is connected to the X coil switching circuit 50a of the control unit 3. Also, the Y terminal of each terminal of one of the Y coils
1, Y2,... Yn and a Y ground electrode GY in which terminals on the ground side of each coil are grouped.
3b is concentrated to the Y connector CNY of the connector 49. The connector 49 is connected to the Y coil switching circuit 50b of the control unit 3. Hereafter, collectively X and Y
This is called a coil switching circuit 50. (See FIG. 9). As an example, in this embodiment, P1 = 50 mm, and P2
X = 680 mm and P2Y = 980 mm. Also, m = 22 and n = 34.

Here, a method of laying the loop coil 23 on the base material 22 will be described in detail. The base material 22 is generally used cloth, and preferably has high insulating properties. In addition, synthetic fibers such as polyester fibers and polyamide fibers are preferable to natural materials that easily absorb moisture because the fibers themselves have some strength and do not expand or contract due to moisture absorption. To ensure insulation between the loop coils 23 laid on both sides of the fabric, a certain thickness is also required. In the present embodiment, as described above, a woven fabric made of polyester fibers is used. As a method of folding a woven fabric, a method of folding with little expansion and contraction such as plain weave is preferable.

In the case of the conventional copper wire covered with an enamel layer, the loop coil 23 lacks flexibility and causes inconvenience during storage and disconnection due to metal fatigue. Naslon (registered trademark) manufactured by Co., Ltd.
Use This NASULON is an extremely thin fibrous SU
S (stainless steel) is a yarn obtained by twisting 100% fibers (hereinafter abbreviated as SUS yarn), and has extremely high flexibility and electrical resistance of several hundred Ω / m or less. It is possible to sew with a sewing machine at the same time.

Next, a method of laying such a SUS yarn on the substrate 22 will be described. The loop coil 23 is composed of the X coil and the Y coil having a phase of 90 ° as described above, and each coil has an elongated and substantially rectangular shape, and is arranged so as to overlap with an adjacent coil every half width. First, SUS yarn
If it is a lockstitch sewing machine, it can be handled. In this case, a case in which the SUS yarn is used as the upper yarn, a case in which the SUS yarn is used as the lower yarn, and a case in which both are used. However, SUS yarn is fairly flexible as a metal, but is inferior in flexibility to other natural fibers or synthetic fibers generally used for sewing. If the SUS thread is used as the upper thread in a lockstitch sewing machine, it will be violently rubbed with the sewing machine balance and the thread, so pretreatment such as impregnating the thread itself with silicone oil is required. There is a possibility that the contact portion with the yarn may be deteriorated. In comparison, when the SUS thread is used as the bobbin thread, the degree of rubbing or bending is relatively small, so that the thread is sufficiently resistant to sewing by the sewing machine. Especially SUS
When the thread is used as the bobbin thread and the lower thread tension is higher than the upper thread tension, the SUS thread is sewn on only the lower surface of the base material 22 in a substantially straight line.

FIG. 19A shows a weft made of SUS (hereinafter referred to as SUS weft 82) as a lower thread and a weft made of spun yarn used for ordinary sewing (hereinafter referred to as a spun weft 81) as an upper thread. And shows a state in which the base material 22 is sewn with the lower thread tension. As shown in FIG. 19A, the SUS weft 8
2 is sewn substantially linearly on the lower surface of the base material 22. Therefore, the SUS weft 82, which is a conductor, is completely insulated from the top of the base 22 without being exposed above the base 22, which is an insulator. Here, FIG.
9 (A), the substrate 22 is turned upside down, and the SUS woof 82 and the spun woof 81 sewn first are subjected to SU.
FIG. 3 is a diagram showing a state in which a warp made of S yarn (hereinafter referred to as SUS warp) and a warp made of spun yarn (hereinafter referred to as spun warp) are sewn at a phase angle of 90 °, and the front and back are returned again. As shown in FIG. 19B, the conductor SU
The S weft 82 is sewn on the lower side of the base 22 and the SUS warp 83, which is also a conductor, is sewn on the upper side of the base 22, so that both are separated by the base 22 which is an insulator. And the continuity is completely cut off. That is, in the above method,
There is no continuity between the warp and the weft at the intersections, and complete insulation can be achieved.

It should be noted that the loop coil 23 is formed of the above-described SU.
Not limited to the S thread, other materials can be used as long as the condition that the resistance is low and that there is sufficient conduction as a coil, and that the material is somewhat flexible and can withstand sewing by sewing is satisfied. For example, a so-called copper wire twisted yarn in which a thin copper foil tape is spirally wound around the surface of a nylon wire is exemplified. Further, it is desirable that the conductive wire having a coating has a sufficient flexibility and abrasion resistance enough to withstand sewing by a sewing machine, and has a coating.

The method of laying the loop coil 23 on the base material 22 is not limited to these, and the following method may be used. If the conductor has a coating capable of providing sufficient insulation, it may simply be laid at a predetermined position.

FIG. 20 is a view for explaining a method of fixing the loop coil 23 with a zigzag sewing machine.
In the case where an uncovered conductive wire is used as in the present embodiment, the loop coil 23 is temporarily placed in a predetermined position in addition to the sewing by the lockstitch sewing machine, and is fixed with a zigzag sewing machine from above. There is a way. According to this method,
It is not suitable for use as a lower thread of a lockstitch sewing machine, but is effective for a material having sufficient flexibility to be folded. As shown in FIG. 20, the SUS warp 83 placed on the base material 22 at a predetermined position is fixed by pressing it with a non-conductive zigzag thread 86.

FIG. 21 shows the SUS warp 83 and the SUS warp.
At the intersection with the weft yarn 82, both the SUS warp yarn 83 and the SUS weft yarn 82 are
FIG. 4 is a diagram showing a state in which both are electrically connected while being fixed to 2. FIG. 22A is a perspective view showing the configuration of the short-circuit crimping member 85, and FIG. 22B is a diagram illustrating the SUS warp 83 and the SUS weft 8 formed on the base material 22 using the short-circuit crimping member 85.
FIG. 3 is a diagram for explaining a process of fixing 2 orthogonally;
FIG. 22 (C) shows the substrate 22 using the short-circuit crimping fitting 85.
FIG. 7 is a view for explaining a state in which a SUS warp 83 and a SUS weft 82 are fixed to be orthogonal to each other.

As shown in FIG.
SUS warp 83, SU, which is the loop coil 23,
The S weft 82 can also be fixed. As shown in FIG. 22A, the short-circuit crimping fitting 85 penetrates into a donut-shaped disk-shaped aluminum alloy washer 85a and a central hole of the washer 85a and is deformed. Thus, a cylindrical base deforming portion 85c to be locked by this and a base 85b provided in the lower part in a flange shape are provided.

To fix the SUS warp 83 and the SUS weft 82 by using the short-circuit crimping fitting 85, FIG.
As shown in the figure, the base deforming portion 85c is inserted into a hole previously formed in a predetermined position of the base material 22, and the SUS weft 8 to be fixed is inserted.
2 is clamped by the base 85b. At this time, the base 85b
There are several protrusions on the upper surface of the
The S weft 82 passes through at least the center of at least one of the protrusions, preferably at a position closest to the center. Then, the other SUS warp 83 to be fixed is temporarily placed so as to come into contact with the base deformed portion 85c exposed from the base material 22, and the washer 85a is raised so that the base deformed portion 85c is inserted into the hole of the washer 85a. Cover from. Then, the SUS warp 83 is arranged on the center side from the plurality of projections projecting below the washer 85a.
Then, from the state shown in FIG.
While pressing the base 5a downward, the base deforming portion 85c is crushed with a special tool, a hammer, or the like, thereby fixing the base deforming portion 85c in a state as shown in FIG.

The SUS warp 83 fixed in this way and the S
The US weft 82 has a washer 85a and a base 85, respectively.
Since it is pressed by b, it is firmly fixed.
Not only that, since the projections provided on the washer 85a and the base 85b are fixed by cutting into the base material 22, they do not come off easily, and the SUS warp 83 and the SUS weft 82 are crushed. Since the contact is made in a wide area, the contact resistance can be reduced, and the surface is hardly oxidized by the close contact.

In place of the short-circuit crimping fitting 85 shown in FIG. 21, a similar fixing pin is made of a highly insulating plastic or the like. If the warp yarn 83 and the SUS weft yarn 82 are fixed, the conduction between them can be prohibited. It is needless to say that the loop coil 23 can be laid by a so-called bonding method in which a pin is inserted into the base member 22 and the loop coil 23 is fixed to the pin tip, not limited to the intersection.

As described with reference to FIG. 5, the X coil has a portion where the X coil intersects at each end. In this embodiment, this portion is processed as follows. . Hereinafter, the X coils 1 to 7 will be described as examples. Here, FIG. 25A shows X coils X1, X3, X
FIG. 5 is a diagram showing a state of an upper end portion of a base material 22 on which X5 and X7 are laid. FIG. 25B shows the base material 22 obtained by folding the base material 22.
FIG. 6 is a view showing a state of an upper end portion of FIG. FIG. 25 (C)
Are the X coils X2, X4,
It is a figure which shows the state of the upper end part of the base material 22 which laid X6. First, as shown in FIG. 25 (A), odd-numbered X coils, here, X coils X1, X3, X5, X7, are laid with a lockstitch sewing machine. At this time, the wire is laid so that the SUS yarn is on the surface. Next, as shown in FIG.
The X coil X1, X3, in which the upper end of the portion where the X coil of No. 2 is not laid is turned back to the surface side and a part thereof is laid.
Cover X5 and X7. Then, as shown in FIG. 25C, the laid X coils X1, X3, X5, X
7, the X coils X2, X4, and X6 are offset downward and laid with the lockstitch sewing machine in the same manner so that the SUS thread is on the surface. At this time, the wires are laid so that the upper ends of the X coils X2, X4, and X6 come on the folded substrate 22. By laying in this way, the X coils X1, X3, X3
X5, X7 and X coils X2, X4, X6 are insulated from each other. Therefore, each X coil can independently detect the induced voltage without being affected by other X coils.

In order to secure continuity at the ground wire consolidation as shown by the short-circuit point S in FIG. 5, a SUS thread is used for both the upper thread and the lower thread, and zigzag stitching is performed. It is possible not only to short-circuit the conductors on the same surface, but also to short-circuit the front and back surfaces.

The Y coil can be insulated by laying it on the surface of the substrate 22 opposite to the surface on which the X coil is laid. Also, the end portion can be configured to be equivalent to the X coil by folding the left end.

As for the line concentrating method, as shown in FIG.
Concentrate the coil terminal 23 to the X coil connector CNX,
The coil terminals 23b are once gathered to the Y coil connector CNY, and these are further combined in the connector 49 shown in FIG. Since the connector 49 is configured to be connectable to the operation unit 30, it can be connected with one touch, can be electrically connected, and can be structurally joined, and the operation unit 30 can be used as a weight as it is.

Here, FIG. 23 shows the S
It is a figure which shows the crimping connector which connects with US weft 82. The crimp connector includes a crimp connector base 71 and a crimp connector retainer 72. On the crimping connector base 71, contact terminals 71a for holding the SUS weft 82 crimped by the crimping connector base 71 and the crimping connector retainer 72 to conduct electricity are provided at positions corresponding to the SUS weft 82. The contact terminal 71a is a SUS weft 82
A pair of metal springs are provided to face each other,
The leading end is widened so that the SUS weft 82 can be easily introduced. In addition, the tip of the contact terminal 71 a is formed in a pointed shape to ensure conduction with the SUS weft 82 sunk into the base material 22 and easily penetrates the base material 22.

The crimp connector retainer 72 is made of SUS weft 8
Reference numeral 2 is for pressing the laid base member 22 against the contact terminal 71b. The crimp connector retainer 72 includes a pair of lock levers 72a protruding toward the crimp connector base 71,
72 a are inserted into lock holes 71 b, 71 b provided in the crimp connector base 71, and
While accurately guiding the position of, was provided inside,
The spun weft 81 is pressed by the yarn presser 72b in accordance with the position of the spun weft 81 so as not to shift the position toward the crimp connector base 71 side. Then, the SUS weft 82 on the opposing surface of the substrate 22 of the spun weft 81 is accurately introduced into the contact terminal 72. Further, when the crimp connector retainer 72 is pressed against the crimp connector base 71, the SUS wefts 82 corresponding to the respective contact terminals 71a are pushed in,
The contact terminal 71a penetrates through the base material 22, and the contact terminal 71a enters the contact terminal groove 72c which is a relief provided in the crimp connector retainer 72, so that the crimp connector retainer 72 presses the span weft 81. The spun weft 81 pushes the SUS weft 82 into the contact terminal 71a sufficiently deep through the base material 22, and the SUS weft 82 is pushed into a portion with a strong clamping force near the base of the contact terminal 71a to ensure reliable conduction. It is planned. The current conducted from the contact terminal 71a is transmitted from the connector 49 (see FIG. 1) to the operation unit 3
0, the position of the pen 60 is detected and the pen attribute is determined.

Next, a position coordinate table for detecting the position coordinates of the pen 60 on the writing surface 21a will be described with reference to FIGS. FIG. 6A shows the X coil X1.
FIG. 6B is an explanatory diagram showing a part of X3.
FIG. 6C is a graph showing the relationship between the voltage generated in the X coils X1 to X3 shown in FIG. 6A and the distance in the width direction, and FIG. 6C is adjacent to the X coils X1 to X3 shown in FIG. 5 is a graph showing a voltage difference between loop coils. FIG. 7 (A)
Is an explanatory diagram showing the position coordinate table as a graph,
FIG. 7B is an explanatory diagram of the position coordinate table.
(C) is an explanatory view showing a storage state of a detection value detected from each X coil.

In FIG. 6, the center lines of the X coils X1, X2, and X3 are C1, C2, and C3, respectively.
1, X2, and X3 are represented by ex1, ex, respectively.
2, ex3. As shown in FIG.
1 to ex3 are the center C1 to C3 of the loop coil, respectively.
, And has a monomodal property that becomes smaller as the end in the longitudinal direction approaches. In addition, each coil is overlapped with a half width of P such that its own null point, that is, the point where the voltage becomes 0 is outside the center of the adjacent coil.
In FIGS. 5A, 5B, and 6A, the width is slightly reduced to make it easy to see how the loop coils 23 overlap. As shown in FIG. 6C, the voltage difference between the mutually adjacent loop coils of the X coils X1 to X3 has the maximum value on the centers C1 to C3 of the loop coils, respectively. The graph becomes zero at the midpoint of the long side portion of the graph, that is, at the midpoint of the portion where the adjacent loop coils overlap.

For example, in FIG. 6C, (ex1-e
x2), the right half of the graph (the part shown by the solid line) is X
Distance between the center C1 of the coil X1 and the intermediate point Q2 of the portion where the X coil X2 is overlapped (1/2 of the overlap pitch,
That is, the relationship between (1/4 of P) and (ex1-ex2) is shown. Now, if the pen 60 exists at the point Q2,
If (ex1-ex2) is detected, the distance ΔX1 from the center C1 to the point Q2 can be detected, so that the X coordinate of the point Q2 can be obtained. In this embodiment, the coil width P1
Is 50 mm, so that P1 / 4 = 12.5 mm. For example, in FIG. 6 (C), when a portion exhibiting the characteristic of (ex1-ex2) (portion drawn by a solid line) is converted into 8-bit digital data, a graph shown in FIG. 7 (A) is obtained. When this graph is converted into a table format, FIG.
The position coordinate table 58a shown in FIG. The position coordinate table 58a is stored in the ROM 58 (see FIG. 9) or the like, and is used for calculating the position coordinates of the pen 60.

Next, the main electrical configuration and control contents of the electronic blackboard 1 will be described with reference to FIGS. 9, 10B and 11. FIG. FIG. 9 is an explanatory diagram showing the electrical configuration of the electronic whiteboard 1 by blocks, and FIG. 10B is an explanatory diagram showing signals at points A, B, and C in FIG. FIG.
10 is a flowchart showing main control contents executed by the CPU 56 shown in FIG. When detecting that the power button 38 (see FIG. 1) is pressed and the power is turned on (step (hereinafter abbreviated as S) 100: Yes), the CPU 56 provided in the control unit 2 shown in FIG. The stored control program and the position coordinate table 58a (FIG. 7)
(B) is loaded into the work area of the RAM 59 (S200), and a coordinate reading / pen information detection process is executed (S300).

Here, the coordinate reading process will be described with reference to FIG. 9 along the flowchart of FIG. 12 showing the flow. The CPU 56 outputs a coil selection signal A (FIG. 10 (B)) for sequentially selecting the X coils X1 to Xm to the X coil switching circuit 50a via the input / output circuit (I / O) 53, so that the X coil X1 To Xm (S302). Subsequently, the signal generated by the magnetic coupling between the alternating magnetic field generated from the coil L1 of the pen 60 and one of the X coils is amplified by the amplifier 50c.
An unnecessary band of the amplified signal (see FIG. 10B) is filtered by a band-pass filter (BPF) 50d.
The amplitude detection is performed by the amplitude detection circuit 51. Subsequently, the amplitude-detected signal (FIG. 10B) is converted into a digital signal corresponding to the amplitude, that is, the voltage value by the A / D conversion circuit 52 and input to the CPU 56 via the input / output circuit 53. .

Subsequently, the CPU 56 determines that the pen 60 has been detected (S304: Yes), scans the X coils X1 to Xm, and obtains the voltage values e1 to em indicated by the input digital signals in FIG. 7C. As shown in (5), it is sequentially stored in the voltage value storage area 59a of the RAM 59 in association with the coil number of the X coil (S306). Then CP
U56 calculates the X coordinate of pen 60 based on each voltage value stored in voltage value storage area 59a by the following procedure (S308). First, the maximum voltage value e among the voltage values e1 to em stored in the voltage value storage area 59a.
After selecting max, the coil number (hereinafter referred to as max) of the X coil that generated the voltage value emax is stored in the RAM.
59. For example, as shown in FIG.
Exists at a position Q3, and as shown in FIG. 6B, voltage values e1, e2,
If e3 occurs, the maximum voltage value e2 is selected,
The coil number 2 of the X coil that generated the voltage value e2 is stored in the RAM 59 as max. And CPU5
The RAM 6 determines the larger of the voltage values emax ± 1 on both sides of emax, and stores the coil number (hereinafter, referred to as max2) of the X coil that generated the determined voltage value in the RAM.
59.

In the example shown in FIG. 6, the voltage value e on both sides of e2
3, e1 is determined to be the larger e3, and its voltage value e
The coil number 3 of the X coil generating 3 is stored in the RAM 59 as max2. Subsequently, the CPU 56
By comparing the coil numbers max and max2 stored in 59, it is determined whether the coil number max2 exists in the + direction or the − direction of the X axis from the coil number max.
If max2 ≧ max, the variable SIDE
Is set to 1 and if max2 <max, the variable S
Set IDE to -1. In the example shown in FIG.
Is in Q3, since max = 2 and max2 = 3, max2> max, and the variable SIDE is set to 1. Subsequently, the CPU 56

DIFF = e (max) −e (max2)

Is calculated, and the position coordinates closest to the calculated DIFF are read from the position coordinate table 58a stored in the ROM 58 and set as OFFSET. Subsequently, the CPU 56

X1 = (P1 / 2) × max + OFFSET × SIDE

Is calculated to obtain an X coordinate X1. here,
(P1 / 2) × max is the X of the center of the coil number max.
Indicates coordinates. In the example shown in FIG. 6, the expression (2) is expressed as X = (P
１ ／) × 2 + (e2−e3) × 1, and the X coordinate of the position Q3 is separated from the center line C2 of the X coil X2 by a distance corresponding to (e2−e3) in the + direction of the X axis, for example, ΔX2. Coordinates. Then, the CPU 56 scans each Y coil (S310), and stores the voltage value detected from each Y coil in the voltage value recording area for the Y coil of the RAM 59 (S312). Subsequently, the CPU 56 proceeds to step S3.
08, using the same method as that for calculating the X coordinate.
Is calculated (S314).

Next, an electrical configuration and control for determining the pen attribute by the CPU 56 will be described with reference to FIGS. FIG. 13 is an explanatory diagram showing an electrical configuration of the FSK demodulation circuit 55 (FIG. 9), and FIG.
FIG. 5 is an explanatory diagram showing signal waveforms appearing at various parts of the FSK demodulation circuit 55 shown in FIG.

FIG. 15A shows an output signal (hereinafter, referred to as a CR signal) of a CR oscillation circuit 69e (see FIG. 8).
The output signal of the LC oscillation circuit 69c (refer to FIG. 8) (hereinafter referred to as a carrier signal) and the output signal of the limiter circuit 54 (refer to FIG. 9) (hereinafter referred to as a limiter output signal).
FIG. 14 is an explanatory diagram showing a relationship between the count value and a count value K by a count circuit 55a (see FIG. 13). FIG. 15B is an explanatory diagram showing how the count value K stored in the shift register 55b (see FIG. 13) shifts.

FIG. 16A shows an absolute value comparator 55.
f (see FIG. 13) and the CPU 5
FIG. 16 is an explanatory diagram showing the relationship with the determination cycle of FIG.
(B) is an explanatory diagram showing how the count value K by the counter 55g moves. FIG. 17 is a flowchart showing the flow of processing (pen attribute detection processing 1) from the count circuit 55a constituting the FSK demodulation circuit 55 to the absolute value comparator 55f in S318.
FIG. 18A is a flowchart showing the flow of the process of the counter 55g in S318, and FIG.
18 is a flowchart showing the flow of the processing of an adder 55i in 18. The carrier signal shown in FIG. 15A has, for example, a center frequency of 410 kHz and a frequency shift of ± 15 kHz as described above. However, in FIG. Exaggerate the shift.

First, FSK for detecting pen attributes
The features of the demodulation circuit 55 will be described with reference to FIG. In the example shown in FIG. 15A, the carrier signal has a high frequency (for example, 425 kHz) during the low level of the CR signal.
z), and is modulated to a low frequency (for example, 395 kHz) during the high level. For this reason,
Assuming that the period of the limiter output signal during the low level of the CR signal is TB, the period of the limiter output signal during the high level of the CR signal is TC longer than TB. Therefore, the count value K for one cycle of the limiter output signal by the count circuit 55a increases when the CR signal changes from a low level to a high level, and decreases when the CR signal changes from a high level to a low level.

That is, by detecting the timing at which the count value K by the count circuit 55a changes, C
The rising or falling timing of the R signal can be detected. Since the time from the change of the count value K to the next change corresponds to a half cycle of the CR signal, if one cycle of the change time of the count value K is measured, Since the period can be obtained, the pen attribute can be detected. Where FSK
An outline of the operation of each component of the demodulation circuit 55 will be described.
The count circuit 55a measures the count value K, and outputs a shift register 55b, a first weighted average circuit 55c, a second weighted average circuit 55d, a subtractor 55e, and an absolute value comparator 5
5f detects the change timing of the count value K, and the counter 55g, the register 55h, and the adder 55i measure the cycle in which the count value K changes. And the CPU 56
Determines the pen attribute based on the added value output from the adder 55i (FIG. 12: S318).

Next, the operation of the FSK demodulation circuit 55 will be described in detail. The signal output from the bandpass filter 50d is converted by the limiter circuit 54 into a square wave limiter output signal shown in FIG.
5 is output. Then, the FSK demodulation circuit 55 detects the rise of the limiter output signal (S1 in FIG. 17).
0: Yes), and starts counting the cycle of the limiter output signal using the system clock (CLK) (S12).
When the next rise of the limiter output signal is detected (S1
4: Yes), the count value K is output to the shift register 55b (S16), and the count value K is reset (S1).
8). That is, the count circuit 55a measures the length TB or TC of one cycle of the limiter output signal.

In this embodiment, the shift register 55
15B, as shown in FIG. 15B, the count value K for one cycle of the limiter output signal is stored for eight cycles of K1 to K8, and every time the newest count value K is taken in, the oldest count value K is stored. Discarding and shifting each counter value K one by one. The first weighted average circuit 55c calculates a weighted average value from the latest count value K stored in the shift register 55b to the third newest count value K, and calculates the weighted average value (hereinafter, referred to as the first weighted average value). ) Is output to the subtractor 55e. The second weighted average circuit 55d calculates a weighted average value from the oldest count value K stored in the shift register 55b to the third oldest count value K, and calculates the weighted average value (hereinafter, referred to as a second average value).
It is called the weighted average. ) Is output to the subtractor 55e.

The subtractor 55e calculates a difference Δm between the first weighted average and the second weighted average, and outputs the difference Δm to the absolute value comparator 55f (S20 in FIG. 17). For example, in FIG. 15A, when the first weighted average circuit 55c calculates the weighted average of the count values K1 to K3, and the second weighted average circuit 55d calculates the weighted average value of the count values K6 to K8, Among the values K6 to K8, since the count values K7 and K8 are obtained by counting the period TC longer than the period TB of the limiter output signal, the second weighted average value is larger than the first weighted average value. Therefore, by detecting that the second weighted average value has become larger than the first weighted average value, it is possible to detect a change point of the period of the CR signal. That is, if the period of the change point of the period of the CR signal is detected, the period of the CR signal can be detected, so that the attribute information of the pen 60 can be recognized.

As described above, the weighted averaging circuit performs the weighted averaging on the count values K counted at a time interval, so that even if a certain count value K is affected by noise, the influence is reduced.

Next, the processing from the absolute value comparator 55f to the adder 55i will be described with reference to FIG. In FIG. 16, 〜 indicates the count value K by the counter 55g. The absolute value comparator 55f calculates the difference Δ
m is compared with a preset threshold value m1, and it is determined whether or not the difference Δm is equal to or greater than the threshold value m1 (FIG. 17).
(S22), when it is determined that the difference Δm is equal to or larger than the threshold value m1 (S22: Yes), the threshold determination output is changed from a low level to a high level (S24). That is, it is determined that the cycle of the limiter output signal has changed (the rising edge of the CR signal has been detected). For example, FIG.
The count value K by the count circuit 55a of the shorter cycle TB of the limiter output signal shown in FIG.
If the count value K is 16 and the threshold value m1 is 2, since the count values K1 to K6 are all 10, the first weighted average value = (K1 + K2 + K3) / 3 = 10. Since the count values K7 and K8 are both 16, the second weighted average value = (K6 + K7 + K8) / 3 = 42/3 =
14 and the difference Δm = 10−14 = −4.

The first weighted averaging circuit 55c and the second weighted averaging circuit 55d are determined based on the ratio between the carrier frequency (the oscillation frequency of the LC oscillation circuit 69c) and the modulation frequency fm, and the circuit complexity. Further, the count value K held by the shift register 55b, that is, the number of periods of the limiter output signal is determined by the ratio of the system clock frequency to the frequency of the carrier, and the frequency of the system clock is large enough to discriminate the change in the frequency. Set to

Therefore, since (absolute value of difference Δm = 4)> (threshold value m1 = 2), the threshold value judgment output changes from low level to high level (FIG. 17: S24). This high level state indicates that the absolute value of the difference Δm is equal to the threshold value m1
The above is maintained until the absolute value comparator 55f determines. When the calculation range of the first weighted averaging circuit 55c and the second weighted averaging circuit 55d reaches a portion passing through the edge of the CR signal, the period of the limiter output signal becomes constant. Calculate the weighted average value of the count value K in the same cycle, the subtraction value by the subtractor 55e becomes 0, and the threshold value determination output remains in the high level state.

On the other hand, when the counter 55g detects that the threshold value judgment output has changed from the low level to the high level (S30 in FIG. 18A: Yes), the time during which the judgment output is at the high level, that is, The half cycle of the judgment output is counted using the system clock (CLK) (S3).
2). Let the count value be K ((B1) in FIG. 16B). When the absolute value comparator 55f determines that the difference Δm is equal to or larger than the threshold value m1 (S22: Yes in FIG. 17), the threshold determination output is changed from a high level to a low level (S24). That is, it is determined that the cycle of the limiter output signal has changed (the falling edge of the CR signal has been detected). Thus, the counter 55g detects that the threshold value determination output has changed from the high level to the low level (FIG. 18A: S34:
Yes), and outputs the count value to the register 55h as shown in (B2) of FIG. 16B (S36). Subsequently, the counter 55g resets the count value (S3
8) Count the time when the threshold value judgment output is at the low level, that is, the half cycle of the threshold value judgment output (circled B, S32). The count value is used.

Subsequently, the adder 55i determines that the timing at which the count value K is held in both the counter 55g and the register 55h, that is, the addition timing (S
50: Yes), the count value held by the counter 55g and the count value held by the register 55h are added (S52), and the added value is output to the CPU 56 (S56). At this time, the counter 55g is
The count value is output to the register 55h as shown in (B3) of (B) (S36 of FIG. 18A). And
The CPU 56 reads the value of the FKS demodulation circuit 55 via the input / output circuit 53, that is, the added value (FIG. 12: S
316, FIG. 13), and determines the pen attribute based on the read addition value (S318). For example, when the added value is 245, it is determined that the pen attribute is black and thick as shown in FIG. Also, the CPU 56
The pen attributes and the XY coordinates are stored in the RAM 59 in association with each other. The writing data stored in this manner is output to, for example, the printer 200 (see FIG. 2) and printed in black. The data is output to the PC 100 (see FIG. 2) and displayed on the monitor 103 (see FIG. 2) in black. That is, the writing data can be reproduced according to the attribute of the pen 60.

Subsequently, the adder 55i adds the count value of the register 55h and the count value of the counter 55g and outputs the result to the CPU 56 ((B) in FIG. 16B).
3)). Thereafter, each time the threshold determination output changes, the count value K of the counter 55g is output to the register 55h, and the adder 55i adds the count value K of the counter 55g and the count value K held in the register 55h. Then, the cycle of outputting the added value to the CPU 56 is repeated. That is, as shown in FIG. 16B, the adder 55i includes the latest count value K counted by the counter 55g and 1 held in the register 55h.
In order to add the previous count value K and output it to the CPU 56, as shown in FIG.
Determines the pen attribute based on the sum of the latest count value K and the previous count value K every half cycle of the threshold value determination output. Therefore, even if the scan of the loop coil 23 is performed in the middle of the threshold determination output, for example, between times t0 and t1 in FIG. Even if the added value of (t2 to t4) is not taken in, one of the times t2 to t4 half a cycle after the time t1 is obtained.
Since it is sufficient to take in the added value of the period, the pen attribute can be determined at high speed. Then, the pen attributes and the XY coordinates are stored in association with each other (S320), and the process is repeated again from the procedure of the X coil scan (S302).

X, Y coil scan (S302, S31)
0) is repeated to start writing with the pen 60 shown in FIG. 1 on the writing surface 21a, and after the pen 60 is detected for the first time (FIG. 1).
2: S304: Yes), the pen 60 is separated from the writing surface 21a until the pen 60 is no longer detected (S304: N).
The pen attributes of the series of pens 60 and the XY coordinates are stored in the locus storage area (not shown) of the RAM 59 (S320). The position of the pen 60 is sequentially stored in the trajectory storage area as the X coordinate and the Y coordinate in the dot matrix arranged in the X-axis and Y-axis directions together with the attributes of the pen. In this manner, when the procedure of the coordinate reading / pen information detecting process (S300) shown in FIG.
Next, page processing (S400) is performed.

Here, returning to the flowchart of FIG. 11, the description will be continued. Coordinate reading / pen information detection processing (S300)
Is completed, the CPU 56 sets the page return button 33,
When the page feed button 34 and the delete button 35 are pressed, page processing (S400) such as returning, sending, or deleting stored writing data in page units is performed. In the page processing, the CPU 56 fetches a switching signal generated by operating various buttons (see FIG. 1) provided on the operation unit 30 via the I / F circuit 57 (see FIG. 9) and stores the switching signal in the RAM 59. A page process such as returning or sending the page storing the position coordinate data in page units, or deleting the position coordinate data in page units is executed. In addition, the CPU 56
9 is converted into an appropriate format from the position data of the target page out of the position data stored in PC1.
00 and a data output process (S500) for outputting to the printer 200 (see FIG. 2).

Further, the CPU 56 (see FIG. 9) operates the audio circuit 31a (see FIG. 9) based on a switching signal generated when various buttons are pressed, and operates the speaker (SP) 31 (see FIG. 9). Then, a voice output process for generating operation sounds such as “P” and “B” is executed (S600).
When one round of processing is completed, the processing from S100 to S600 is repeated (return, S100 to S600).

The electronic blackboard 1 according to the embodiment of the present invention comprises:
With the above configuration and operation, the following effects can be obtained. That is, when used as the electronic blackboard 1, an alternating magnetic field of a predetermined frequency is generated by the pen 60 provided with the oscillation coil L1, and is formed of a plurality of conductive thread members laid on the cloth base material 22 which is an insulator. Loop coil 2
3 is magnetically coupled to the alternating magnetic field,
There is an effect that the coordinates of the locus of the pen 60 drawn on the writing portion can be read from the voltage induced in the loop coil 23 and recorded electronically. When not used, the base material 22 is made of cloth and the loop is not used. Since the coil 23 is also made of a conductive thread-like member, it is extremely light and can be folded small, and has an effect that storage, transportation and the like become extremely easy.

Further, since the loop coil 23 is made of stainless steel (SUS) having no coating, there is an effect that the electric resistance can be reduced. Therefore, reception with a good S / N ratio can be performed.

The SUS thread is formed in a fibrous form and has flexibility, so that it can be used for a sewing machine. Since the loop coil 23 is sewn to the base material 22 made of cloth with a lockstitch sewing machine, the SUS thread is easy and easy to use. There is an effect that the loop coil 23 can be efficiently laid. Further, there is an effect that the laid loop coil 23 can be firmly fixed to the base material 22.

In particular, in the present embodiment, the sewing is performed so that only the one side of the base material is exposed by adjusting the thread tension with the lockstitch sewing machine, so that the loop coil can be easily insulated. Then, the loop coil 2 is formed by one cloth base material 22.
There is an effect that a plurality of loop coils 23 can be arranged in parallel so as to overlap the adjacent loop coils 23 by a fixed width while maintaining insulation between the three loop coils. For this reason, since the front and back sides can be insulated, in the present embodiment, the Y coil is laid with a phase of 90 ° on the back surface of the base material on which the X coil is laid on one surface.

Then, there is an effect that the loop coils 23 can be reliably short-circuited by the short-circuit crimping fitting 85 at a concentrating portion where a short-circuit between the loop coils 23 is required. Also, there is an effect that the loop coil can be securely fixed.

Although the present invention has been described based on one embodiment, the present invention is not limited to the above-described embodiment, and may be modified as follows. For example, the method of laying the loop coil may be performed by using the lock stitch sewing machine or the zigzag sewing machine described above, or by using the short-circuit crimping fitting 85, or the loop coil 23.
May be attached to a sewing needle and penetrated by a predetermined distance through the base material 22 by hand, and alternately exposed and sewn on the front and back sides, and then fixed. By doing so, it is possible to securely place the wire in a place where the sewing machine is difficult to use or when it is desired to prevent an inadvertent short circuit.

The base member 22 constituting the writing portion 21 is formed of one sheet, and the X coil and the Y coil are laid on the front and back of the base member 22, respectively. It is also possible to configure with four sheets. Although this configuration increases the thickness, it has the effect of simplifying the configuration at the intersection or loop overlap.

When only the upper thread is made of SUS thread and sewn from above with a patch cloth applied at the intersection, a crossing pattern on only one side can be realized. In this case, if there is a needle drop at the intersection, there is a possibility of a short circuit. Therefore, the sewing machine is temporarily stopped just before the intersection, and the pitch can be increased only at the intersection to avoid this danger.

Further, the connection method with the loop coil 23 laid on the writing portion 21 is not limited to the crimping connector base 71 and the crimping connector retainer 72, but can be conducted by being sandwiched by a spring-type contact and made conductive. It may be a simple connector, and if this connector is removed, a more compact configuration can be achieved. Then, using a SUS thread sewing pattern such as a round hole type or a button hole, and a button-shaped conduction metal fitting hooked here, an electrical connection or cloth to the loop coil 23 laid on the writing portion 21 is made. May be configured to be used for short-circuiting on both sides of.

Further, if a small writing section 21 is manufactured, snap buttons are attached to its four corners, and it is wound around the wrist, the writing section 21 can be wound at the position wound around the wrist.
It becomes possible to input coordinates to some extent.

It should be noted that the present invention is not limited to the above-described embodiment at all, and it can be easily inferred that various improvements and modifications can be made without departing from the spirit of the present invention.

[0110]

As is apparent from the above description, according to the coordinate input device of the first aspect of the present invention, when used as a coordinate input device, an alternating magnetic field of a predetermined frequency is generated by a transmission unit having an oscillation coil. A writing section having a loop coil formed of a plurality of conductive thread-like members laid on a cloth substrate which is an insulator is magnetically coupled to the alternating magnetic field, and writing is performed from a voltage induced in the loop coil. There is an effect that the coordinates of the trajectory of the transmission unit drawn on the unit can be read and output. When not used, the base material is made of cloth, and the loop coil is also made of a conductive thread-like member, so that it is extremely light. And can be folded small,
There is an effect that storage, transportation, and the like become extremely easy.

In the coordinate input device according to the second aspect of the present invention,
In addition to the effect of the coordinate input device according to the first aspect of the present invention, since the loop coil is formed of an uncoated conductive yarn, flexibility can be increased as compared with the case where the coated loop coil is used. This has the effect.

In the coordinate input device according to the third aspect of the present invention,
In addition to the effect of the coordinate input device of the invention according to claim 2, there is an effect that the electric resistance can be reduced because the loop coil is made of stainless steel. Therefore S /
Reception with good N ratio can be performed. Further, there is an effect that it is formed in a fibrous shape and has flexibility. Therefore, there is an effect that the flexibility of the base material is not impaired even if the wiring is laid on the base material.

In the coordinate input device of the invention according to claim 4,
In addition to the effects of the coordinate input device according to the invention according to any one of claims 1 to 3, the loop coil is sewn to a cloth substrate by a lockstitch sewing machine, so that the loop coil can be easily and efficiently formed. There is an effect that it can be laid. Also, there is an effect that the laid loop coil can be firmly fixed to the base material.

In the coordinate input device of the invention according to claim 5,
In addition to the effect of the coordinate input device according to the fourth aspect of the present invention, since the sewing is performed so that only the one side of the base material is exposed by adjusting the thread tension with the lockstitch sewing machine, the loop coil can be easily insulated. .

In the coordinate input device of the invention according to claim 6,
In addition to the effect of the coordinate input device of the invention according to claim 5, while maintaining insulation between loop coils with one cloth base,
There is an effect that a plurality of loop coils can be arranged in parallel so as to overlap with adjacent loop coils by a fixed width. Further, it is possible to lay another set of loop coils with a phase of 90 ° on the back surface of the base material on which one set of loop coils is laid.

In the coordinate input device of the invention according to claim 7,
In addition to the effects of the coordinate input device according to any one of the first to third aspects of the present invention, the loop coil can be manually sewn to a place where a lockstitch sewing machine or the like cannot be used or a loop coil material that is not suitable for the sewing machine. There is an effect that it can be laid.

In the coordinate input device of the invention according to claim 8,
In addition to the effects of the coordinate input device according to any one of the first to third aspects of the present invention, even if the material of the loop coil is difficult to be sewn to the base material, the wire is securely laid in a so-called wire bonding manner. There is an effect that can be.

In the ninth aspect of the present invention, the coordinate input device
In addition to the effect of the coordinate input device of the invention according to claim 8, there is an effect that the loop coils can be reliably short-circuited at a concentrating portion where a short-circuit between the loop coils is required. Also, there is an effect that the loop coil can be securely fixed.

In the coordinate input device according to the tenth aspect of the present invention, in addition to the effects of the coordinate input device according to any one of the first to third aspects, even when sewing with a lockstitch sewing machine or the like is difficult, There is an effect that it can be firmly fixed to one side of the base material.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a receiving unit 10 of an electronic whiteboard 1;

FIG. 2 is an external view showing a main configuration of the electronic blackboard 1;

FIG. 3 is an explanatory diagram showing an internal structure of a pen 60.

FIG. 4 is an explanatory diagram showing each component of the writing unit 21;

FIG. 5A is an explanatory view showing a configuration of the loop coil 23 shown in FIG. 4 with a part thereof omitted; (B) It is explanatory drawing which shows the width | variety and overlap pitch of the loop coil 23 shown in FIG. 5 (A).

FIG. 6A is an explanatory view showing a part of X coils X1 to X3. FIG. 7B is a graph showing the relationship between the voltage generated in the X coils X1 to X3 shown in FIG. 6A and the distance in the width direction. 7C is a graph showing a voltage difference between mutually adjacent loop coils of the X coils X1 to X3 shown in FIG.

FIG. 7A is an explanatory diagram showing a position coordinate table as a graph. (B) It is explanatory drawing of a position coordinate table. (C) It is explanatory drawing which shows the storage state of the detection value detected from each X coil.

FIG. 8 is an explanatory diagram showing an electrical configuration of the pen 60 shown in FIG.

FIG. 9 is an explanatory diagram showing the electrical configuration of the electronic blackboard 1 by blocks.

FIG. 10A is a diagram illustrating a relationship between an attribute of a pen 60 and a modulation frequency fm. (B) It is explanatory drawing which shows the signal in point A, B, and C in FIG.

11 is a flowchart showing main control contents executed by a CPU 56 shown in FIG.

FIG. 12 is a flowchart illustrating a flow of a coordinate reading process.

13 is an explanatory diagram illustrating an electrical configuration of an FSK demodulation circuit 55. FIG.

14 is an explanatory diagram showing signal waveforms appearing at various parts of the FSK demodulation circuit 55 shown in FIG.

FIG. 15A shows an output signal of a CR oscillation circuit 69e;
FIG. 9 is an explanatory diagram showing a relationship among an output signal of an LC oscillation circuit 69c, an output signal of a limiter circuit 54, and a count value K by a count circuit 55a. (B) is an explanatory diagram showing how the count value K stored in the shift register 55b shifts.

16A is an explanatory diagram showing a relationship between a threshold determination output by an absolute value comparator 55f and a determination cycle of a CPU 56. FIG. (B) It is explanatory drawing which shows a mode that the count value K by the counter 55g moves.

FIG. 17 is a flowchart showing the flow of processing (pen attribute detection processing 1) from the count circuit 55a to the absolute value comparator 55f that constitutes the FSK demodulation circuit 55.

FIG. 18A is a flowchart showing the flow of processing of a counter 55g in S318. (B) S3
18 is a flowchart showing the flow of the processing of an adder 55i in 18.

FIG. 19 (A) A weft thread (hereinafter referred to as S
US Weft 82. ) Shows a state where the base 22 is sewn at the lower thread tension using a weft thread (hereinafter referred to as a spun weft thread 81) of a spun thread used for ordinary sewing as the upper thread. (B) The substrate 22 is turned upside down from the state shown in FIG. 19A, and the SUS weft 82 and the span weft 81 sewn first and the warp of SUS yarn (hereinafter referred to as SUS warp) and span It is a figure which shows the state which sewed the warp by a thread (henceforth a span warp) with a 90 degree phase angle, and turned back and front again.

FIG. 20 is a diagram illustrating a method of fixing the loop coil with a zigzag sewing machine.

FIG. 21 shows a SUS warp 8 using a short-circuit crimping fitting 85 at an intersection between a SUS warp 83 yarn and a SUS weft 82.
FIG. 4 is a view showing a state in which both the SUS weft 3 and the SUS weft 82 are fixed to the base material 22 and the two are electrically connected.

FIG. 22 (A) is a perspective view showing a configuration of a short-circuit crimp fitting 85. (B) SUS is applied to the base material 22 using the short-circuit crimping fitting 85
It is a figure explaining the process which fixes warp 83 and SUS weft 82 so that it may intersect perpendicularly. (C) SUS is applied to the base material 22 using the short-circuit crimping fitting 85.
It is a figure explaining the state where warp 83 and SUS weft 82 were fixed so that it might intersect perpendicularly.

FIG. 23 is a view showing a crimping connector for connecting to a SUS weft 82 laid on a base member 22.

FIG. 24 (A) is a perspective view showing a state where an upper support bar 45 is extended. (B) It is a perspective view showing the state where upper support bar 45 was stored.

FIG. 25 (A) is a diagram showing a state of an upper end portion of a base material 22 on which X coils X1, X3, X5, and X7 are laid. (B) It is a figure which shows the state of the upper end part of the base material 22 which folded back the base material 22. (C) X coil X2, X
It is a figure which shows the state of the upper end part of the base material 22 which laid 4 and X6.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electronic blackboard 10 Receiving part 21 Writing part 21a Writing surface 22 Base material 23 Loop coil 30 Operation part 45 Upper support bar 46 Lower support bar 60 Pen (writing means)

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitsugu Tomomatsu 15-1 Naeshiro-cho, Mizuho-ku, Nagoya F-term (reference) in Brother Industries, Ltd. 5B068 AA05 AA15 AA33 BB14 BC03 BC08 BC13 BE08 BE12

Claims (10)

[Claims] A transmitting unit having an oscillation coil for generating an alternating magnetic field of a predetermined frequency; a cloth base material serving as an insulator; and a plurality of magnetic fields capable of being magnetically coupled with the alternating magnetic field laid on the base material. A coordinate input device, comprising: a writing unit having a loop coil formed of a conductive thread-like member; and a receiving unit that reads and outputs coordinates of a locus of a transmission unit drawn on the writing unit. 2. The coordinate input device according to claim 1, wherein the loop coil is formed of an uncoated conductive yarn. 3. The coordinate input device according to claim 2, wherein the loop coil is a stainless steel thread formed into a flexible fibrous shape. 4. The coordinate input device according to claim 1, wherein the loop coil is sewn and laid on the base material by a lockstitch sewing machine. 5. The loop coil as a lower thread, an insulator thread as an upper thread, a thread tension is adjusted by the lockstitch sewing machine, and the loop coil as a lower thread is exposed only on one surface of the base material. The coordinate input device according to claim 4, wherein the coordinate input device is sewn and fixed. 6. A plurality of loop coils are arranged in parallel on one surface side of the base material so as to overlap with adjacent loop coils by a predetermined width, and the loop coil has a laying wire. At the time, after laying a part of the loop coil, at the longitudinal end of the loop coil, the base material is folded back by a predetermined width so as to cover the end of the already laid loop coil, The coordinate input according to claim 5, wherein an end in the longitudinal direction of the loop coil to be laid is laid so as to come to an end portion of the base material folded back by a predetermined width. apparatus. 7. The coordinate according to claim 1, wherein the loop coil is penetrated through the base material at a predetermined interval, and is exposed and fixed alternately on the front and back sides. Input device. 8. The coordinate input device according to claim 1, wherein said loop coil is fixed to a loop coil fixing means fixed through said base material. 9. The method according to claim 8, wherein the loop coil fixing means is made of a conductor, and simultaneously fixes the loop coils on both surfaces of the base material, and short-circuits the fixed loop coils. Coordinate input device as described. 10. The apparatus according to claim 1, wherein the loop coil is fixed on one surface side of the base material so as to be pressed down by a thread made of an insulator sewn with a zigzag sewing machine. The coordinate input device according to any one of the above.