JPS6247730A - Position detecting device - Google Patents

Abstract

PURPOSE:To improve the detecting accuracy together with improvement of the operability with a position detector by using the magnetic matters and the 1st and 2nd coils orthogonal to these magnetic matters to form a position detecting part and combining partially both coils in the phases adverse to each other. CONSTITUTION:A position detector consists of a position detecting part 10, an input pen 20, a signal selecting circuit 30 and a position detecting circuit 40. The part 10 is formed with plural long magnetic matters 11 set in parallel with each other, the 1st coils 12 and the 2nd coils 13 wound round the coils 12. While two coils 12 are combined with the coils 13 in the phases adverse to each other. At the same time, the alternating current is always is applied to the coils 13 in a prescribed cycle. Then the voltage induced at said two selected coils 12 or the coils 13 are extracted successively. Thus a position designated by the pen 20 can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a method for specifying a position by using a C1 position specifying magnetic generator based on a change in magnetic permeability of a magnetic body to which a magnetic field is applied by the position specifying magnetic generator. The present invention relates to a position detection device for detecting a position.

(Prior Art) As a conventional position detection device, a pulse current is applied to a drive coil provided at one end of a magnetostrictive transmission medium or the tip of a position indicating pen to generate magnetostrictive vibration waves in the magnetostrictive transmission medium. , the tip of the position indicating pen or Is is installed at one end of the magnetostrictive transmission medium to cause the detection coil to receive an induction signal based on the magnetostrictive vibration waves.
There is a method in which the time taken to detect the g voltage is measured with a processor or the like, and the indicated position of the position indicating pen is calculated from this. In addition, another conventional position detection device C arranges a plurality of drive lines and detection lines perpendicular to each other, and detects induced voltage by sequentially selecting the detection lines while passing current to the drive lines. There was a device in which a position specified by a position indicating pen made of a magnetic material such as ferrite was detected from the position of a detection line where a large induced voltage was induced.

(Problem that the invention is trying to solve) The former device has relatively good position detection accuracy, but because timing signals, etc. are sent and received between the pen and the processor, there is a problem between the pen and the device. It requires a cord, which severely limits its handling, and it also has the potential to malfunction due to being guided by other devices, or even become a source of noise. It had to be held vertically and pointed fairly close together.

In addition, in the latter device, the positioning pen can be cordless, but the resolution of the coordinate position is determined by the spacing between the lines, and if the spacing between the lines is made small to increase the resolution, the S/N ratio and stability will deteriorate. It is difficult to increase the resolution, it is difficult to detect the position directly above the intersection of the drive line and the detection line, and the position indicator pen must be placed extremely close to the line, which makes it difficult to detect the position directly above the intersection of the drive line and the detection line. I couldn't put things down and use it. Furthermore, conventionally, when trying to associate the timing of position input with pen operation, it was necessary to attach a switch or some kind of signal generation circuit to the pen itself, which led to problems such as a complicated configuration and easy failure. there were.

The present invention overcomes these conventional drawbacks by several times,
To provide a highly accurate position detecting device which has good operability since a magnetic generator for specifying a position is not connected anywhere, is strong against external guidance, and does not emit noise.

(Means for Solving the Problems) As shown in FIG. A plurality of first coils 12a to 1 are arranged at predetermined intervals in a direction perpendicular to the longitudinal force plane.
2j, and a second coil wound almost entirely around the plurality of magnetic bodies 11 and the plurality of first coils 12a to 12j.
- a position detecting unit 10 having a coil 13; a position specifying magnetic generator that generates a steady magnetic field, for example, an input pen 20; and two of the plurality of first coils 12a to 12j. A signal selection circuit 30 that connects the second coil 13 so that they are in opposite phases to each other and sequentially switches and connects the second coil 13; Coils 12a-1
The induced voltage induced in each of two of the first coils 12j is sequentially extracted from the signal selection circuit 30, or an alternating current of a predetermined period is applied to each of two of the first coils 12a to 12j via the signal selection circuit 30. and a position detection circuit 40 which successively extracts induced voltages induced in the second coil 13 when the voltages are switched and applied one after another, and determines the specified position on the position detection unit 10 by the input pen 20 from these. .

(Function) When an alternating current (for example, a sine wave) is passed through the second coil 13, a magnetic flux (magnetic field) is generated around it, and an induced voltage is generated in each of the first coils 12a to 12j due to electromagnetic induction due to this magnetic flux. occurs. This electromagnetic induction is caused by the magnetic material 11
Therefore, the larger the magnetic permeability μ of the magnetic body 11, the larger the voltage value of the induced voltage. Expressing this in a formula, the induced voltage V is: V = L (di/dt) - μ・sN2/J (di/dt
) ...(1) (where, S is the cross-sectional area of the first coils 12a to 12j, N is the number of turns of the first coils 12a to 12j, and p
is the length of the first coils 12a to 12j. ).

By the way, the magnetic permeability μ of the magnetic body 11 changes greatly depending on a steady magnetic field (hereinafter referred to as magnetic bias) applied from the outside. The shape of the change varies depending on the composition of the magnetic material, the frequency of the AC signal, or whether the magnetic material is subjected to heat treatment or magnetic field treatment, but here, as shown in Figure 2, a slight magnetic bias was applied. It is assumed that it reaches a maximum at some times, and decreases as more magnetic bias is applied. Note that the direction in which the magnetic bias is applied is the longitudinal direction of the magnetic body 11, and hereinafter this will be referred to as the X direction.

When one end of the input pen 20 containing the bar magnet 21 is positioned above the magnetic body 11, as shown in FIG. 3!
If! The magnetic flux output from the bar magnet 21 crosses the i-body 11. At this time, the magnetic flux is almost perpendicular to the magnetic body 11 immediately below the bar magnet 21, and gradually follows the magnetic body 11 on both sides thereof. The magnetic bias applied in the longitudinal direction of the magnetic body 11 increases as the angle at which the magnetic flux intersects the magnetic body 11 becomes smaller. Therefore, it is smallest immediately below the bar magnet 21 of the input pen 20, and gradually increases as the distance from there increases. grow bigger,
As you move further away, it gradually becomes smaller.

At this time, the relationship between the position (displacement) X in the X direction on the magnetic body 11 (where O is the position directly below the bar magnet 21) and the magnetic bias 11Hx is expressed as +((h+d)
+x ))...(2) ((u, where m is the strength of the magnetic pole of the bar magnet 21, h is the strength of the magnetic pole of the bar magnet 21
The distance between one end of and the magnetic body 11, d is the length of the bar magnet 21,
μ0 is the magnetic permeability of vacuum. ). This situation is shown in Figure 4.

From FIGS. 2 and 4, the relationship between the magnetic permeability μ of the magnetic body 11 and the position X in the X direction at this time is as shown in FIG.

On the other hand, the first coils 12a to 12j are connected to the signal selection circuit 30.
As a result, two of the coils (hereinafter referred to as coil Kl and 2) are connected to the second coil as shown in FIG.
The coils 13 are combined so as to have opposite phases to each other. Here, add 1 to the coil. The inductance of 2 is Ll,
When L2 is the inductance of the second coil 13 and L3 is the inductance of the second coil 13, the mutual inductance M1 between the coil 1 and the coil 13 and the mutual inductance M2 between the coil 2 and the coil 13 are as follows.

M1=13-11 (
3) M2=L3-L2...
・(4) At this time, 1. For example, (K1.
2>= (12a, 12c), (12b, 12e),
(12d, 120), (12f', 12i), (12h
, 12j) and the coil Kl.

When the positions of K2 and the bar magnet 21 are changed, the mutual inductance M1. M2 also changes as shown in FIG. Here, the first coils 12a to 12j
If the interval between each coil is a, then the switching interval is 2
a, and the distance between the paired coils is 3a (however,
The interval when only both ends are switched is 81, and the interval between the coils is 2a. ).

As mentioned above, coils 1 and 2 are connected in opposite phase to coil 13, so in the circuit shown in FIG. 6, there are two mutual inductances in the vicinity between terminals B and B. M1. A voltage proportional to the difference in M2 is obtained.

Therefore, as mentioned above, 1. 2, a voltage value obtained by sampling a signal corresponding to the difference between the signals of a pair of coils with an interval 3a at an interval 2a as shown in FIG. 8 is obtained. Here, the point P where the voltage value is "0" is the mutual inductance M1. M2 is equal, i.e. bar magnet 21 to 2
1 in one coil. This shows a case where the distances from 2 to 2 are exactly equal, and from this the position of the bar magnet 21 can be detected.

The curve shown in FIG. 8 approximates several voltage values when the first coils 12a to 12j are switched as described above, and in reality, such continuous values cannot be obtained. . However, the upper limit of the frequency component of this approximate signal is approximately proportional to 6a, and its sampling frequency is proportional to 2a as described above, so according to the well-known sampling theorem, it is possible to reproduce the approximate signal from the voltage value. become.

In the present invention, the aforementioned discrete voltage value signal is detected and converted into a DC voltage detection signal, which is roughly passed through a predetermined low-pass filter to form a continuous signal as shown in FIG. P is detected, and the position of the bar magnet 21 is detected.

The first method of detecting point P is to level shift the detection signal shown in FIG. 8 by a predetermined value Vt, then finely sample it and convert it into analog/digital data, which corresponds to the level shift value as shown in FIG. 9. By finding the ratio (b:c) at the coil switching timing of the point P' that crosses the level Vt,
At the same time, from the inclination at point P, the height direction of the bar magnet 21, that is, the input ben 20, and below, Z
It is called direction. ) can be calculated.

In addition, as a second detection method for point P, the count value of a counter that counts a predetermined clock pulse is decoded to generate a switching timing signal for the signal selection circuit 30, and the detection signal shown in FIG. It is also possible to detect the timing of the point P with a predetermined comparator and calculate the position of the point P in the X direction from the count value of the counter at this time.

(Example) FIG. 10 is an exploded perspective view showing a specific configuration of the position detection section 10. In the figure, 110a.

110b is a shield plate; 120a to 120c are magnetic plates; 130a and 130b are conductor plates; The plates 110b are stacked in this order.

The shield plates 110a and 110b are printed circuit boards in which a non-magnetic metal plate, for example a copper plate 112, is attached to one side of an insulating substrate 111 made of glass epoxy or the like.

As shown in FIG. 11, each of the magnetic plates 120a to 120C has a plurality of long magnetic bodies 11 (eight in the illustrated example) arranged almost parallel to each other, and is bonded to two insulating substrates 121 made of glass epoxy or the like. , 122, and are integrated by heat compression bonding or the like. Here, as the magnetic body 11, a material that is difficult to be magnetized even when a magnet is avoided, that is, has a small coercive force and has a high magnetic permeability, for example, an amorphous wire having a circular cross section and a diameter of about 0.1 M is used. As an amorphous wire, for example (F e 1-x COx)
75Si1oB15 (atomic %) (x indicates the ratio of Fe and CO and takes a value of 0 to 1) is suitable.

As shown in FIG. 12, the conductor plates 130a and 130b are made by etching a printed circuit board 131, which is an insulating substrate made of glass epoxy or the like with a copper plate attached to one side, and has a plurality of (21 in the illustrated example) lands at both ends. It is formed by forming a linear conductor 132 having holes.

The respective substrates are bonded and fixed using an adhesive sheet. At this time, the magnetic bodies 11 of the magnetic plates 120a to 120C are arranged along the X direction, and the conductive plate 130a.

The conductor 130b is arranged in a direction perpendicular to the X direction.

In addition, as another manufacturing method, a printed circuit board is bonded and fixed to both sides of the magnetic plate, and then a conductor is formed by etching treatment, or the conductor is not formed, and the shield plate 11 is
0a, magnetic plate 120a, fat plate? 30a, conductor plate 130b, lti conductor plate 120c.

It is also possible to create a set of shield plates 110b, sandwich the magnetic plate 120b between them, and roughly adhere and fix them. The overall thickness of the position detection unit 10 is actually 2 to 3 mm.
However, in FIGS. 10 to 12, only the thickness direction is shown enlarged.

Each of the conductors of the conductor plates 130a and 130b is connected to the conductors that overlap below -F by through-hole processing at a land hole at one end, and a first coil is wound around the magnetic body 11 in the magnetic body plate 120b. 12a to 12j and the second coil 13 are formed alternately. Both ends of the first coils 12a to 12j are connected to the signal selection circuit 30, and the other end of the second coil 13 on the conductor plate 130a side is connected to the adjacent second coil 13.
is connected to the other end of the second coil 13 on the conductor plate 130b side, that is, connected in series, and both ends of the second coil 13 are connected to the position detection circuit 40.

In addition, J5 is located in the position detecting section 10, and the magnetic plate 120
a, 120c constitutes a path for the magnetic flux generated around the coil by the magnetic material 11 therein as shown in FIG. .

Further, the shield plates 110a and 110b are used to prevent the ingress of noise from the outside and the emission of induced noise to the outside, and do not need to be provided.

FIG. 14 shows another example of the magnetic plate, in which a large number of insulating fibers 9 [1123] are arranged almost parallel to each other, and the insulating fibers 1
A warp group (or weft group) 124 in which a plurality of elongated magnetic bodies 11 are arranged at predetermined intervals between 23 and a weft group (or warp group) 126 consisting of a large number of insulating fibers 125 are plain woven, It is made into a woven fabric and then hardened with an insulating resin such as epoxy resin to form a plate. According to this magnetic plate, the thickness can be made smaller, and the position detection section 10 can be constructed even thinner. Note that the insulating fiber 123
For example, glass fiber is used as the 125°.

In addition, although each 1fiifi and the magnetic body are shown separated from each other in the drawing, they are actually configured without any gaps, and two pieces of &1Iff are arranged between the magnetic bodies. In reality, the number of fibers required to maintain the spacing between the magnetic bodies is arranged.

FIG. 15 is a sectional view showing a specific example of the input pen 20, and FIG.
The figure is its electrical circuit diagram. In the figure, 22 is a pen-shaped container made of synthetic resin or the like, and the above-mentioned bar magnet 21 is housed in one end of the pen-shaped container so as to be movable in the axial direction.

In addition, an infrared transmitting window 23 made of transparent plastic or the like is provided along the circumferential direction on the other end side of the container 22, and inside the window 23 is a reflector 24 having a conical circumferential surface coated with chrome plating or the like. An infrared light emitting diode 25 is housed therein. 26a and 26b are operation switches, and the operation switch 26
a is attached to one side of the tip side of the container 22, and an operation switch 26b is attached opposite to the other end of the bar magnet 21. Further, 27 is a signal generation circuit, 28 is a battery, and the container 2
It is stored in the appropriate place within 2. The signal generation circuit 27 performs a plurality of (
It converts each of three commands into a plurality of code signals by combining several pulse signals, and includes a decoder 27a, a code signal generator 27b, and a diode driving transistor 27c, and an operation switch 26a.
, 26b, a code signal is generated to drive the light emitting diode 25. When the operation switch 26a is turned on, an infrared signal indicating a code to start measurement is transmitted from the diode 25 through the reflector 24 and the transmission window 23, and the tip of the bar magnet 21 with the cover 29 attached thereto. When pressed against the surface manually, the bar magnet 21 slides (switch 26b is turned on and an infrared signal indicating a position input code signal is emitted).

FIG. 17 shows a specific example of the signal selection circuit 3o, in which 31 is a multiplexer and 32 is an amplifier. The multiplexer 31 is a well-known device having one common terminal and a plurality of selection terminals (5g in the illustrated example). are switched and connected to sequentially configure the circuit shown in FIG. A common terminal of the multi-brevener 31, ie, a detection terminal B-13 of the circuit, is connected to a position detection circuit 40 via an amplifier 32.

FIG. 18 is a circuit block diagram showing a specific configuration of the position detection circuit 40, and FIG. 19 is a diagram showing signals of each part. When an infrared signal indicating a measurement start code is emitted from the light emitting diode 25 of the input vent 20 mentioned above, the infrared signal is received by the infrared receiving diode 401r, further amplified and waveform-shaped by the receiver 402, and converted to the original signal. It is converted into a code signal, and further converted back into a measurement start command signal, and sent to the arithmetic processing circuit (CPU) 403. When the arithmetic processing circuit 403 reads the command signal and recognizes the start of measurement, it sends a switching signal S1 to the signal selection circuit 30 via the decoder 404, and also sends the clock pulse to the frequency divider 40.
5 to a drive current source 406, the drive current source 40
6 inputs a drive current to the coil 13.

At this time, the output voltage of each coil circuit constituted by the first coils 12a to 12j is sent to the detector 407 via the multiplexer 31 and the amplifier 32, where it is rectified and converted into a DC voltage detection signal S2, Even lower range ([
corpus) filter 408 and converted into a detection signal S3. The detection signal S3 is level-shifted by a level shifter 409 to become a positive voltage signal, further sampled and digitized by an analog-to-digital (A/D) converter 410, and sent to an arithmetic processing circuit 403. The arithmetic processing circuit 403 detects a point P that matches the level shift value described above from the digital value, calculates the coordinate xp of the bar magnet 21, that is, the input ben 20 in the X direction from that timing, and The height h of the input bench 20 is calculated accordingly.

The X coordinate value xp of the digital value obtained in this way
(or the coordinate value xp and the height h) are temporarily stored in the memory in the arithmetic processing circuit 403, but while the signal is being issued without indicating the start of the measurement, the above-mentioned measurement and calculation are carried out in a predetermined manner. It is repeated every hour and its value is updated. next,
When an infrared signal indicating a position input code is transmitted from the input ben 20 and recognized by the arithmetic processing circuit 403 via the light receiving diode 401 and the receiving m402, the X coordinate value of the digital value at that time is inputted as the input value. The data is sent to a digital display (not shown) or the like for display, or sent to another computer device 50 for processing.

FIG. 20 shows a specific example of the drive current source 406, in which 61 is an integrating circuit, 62 is a band pass filter, and 63 is a specific example of the drive current source 406.
is a power driver. The integrating circuit 61 receives at its input terminal 64 a clock pulse (or a pulse obtained by frequency-dividing the clock pulse) from the arithmetic processing circuit of the position detecting circuit 40, integrates it, and converts it into a triangular wave signal. The bandpass filter 62 converts the triangular wave signal into a sine wave signal. The power driver 63 is connected to the A amplifier and the current amplifier, current-amplifies the sine wave signal, and sends it to the signal selection circuit 30 from its output terminal 65. Note that the reason why a clock pulse is used as the reference (input) signal is to synchronize with the position detection circuit 40.

In the embodiments described above, signals indicating measurement start, position input, etc. were transmitted from the input vent 20 to the position detection circuit/10 using infrared signals, but ultrasonic signals may also be used.

Furthermore, since these signals are simply used to make the arithmetic processing circuit 403 recognize the timing of the start of operation of the position detection circuit 40 and the input of coordinate values, they do not particularly need to be sent from the input vent 20; The signal may be sent from a keyboard or other switch circuit provided in the circuit 40 itself.

It is also possible to use the height of the input ben 20 as a parameter for position input. In other words, the measurement start signal is sent from the keyboard or other switch circuit, and in this state, one end of the input ben 20 is connected to the position detection unit 10. When the height h becomes a predetermined value, for example, 0.5 feet or less on the input surface, the arithmetic processing circuit 403 detects this and recognizes it as a position input signal.

Figure 21 shows the input vent 70 used at this time.
A bar magnet 73 with a tapered tip is housed in one end 72 of a pen shaft-shaped container 71 made of synthetic resin with the N pole facing toward the tip, and a cover 74 made of plastic or the like is attached to the tip of the bar magnet 73. It's on. Therefore, it is not necessary to provide the input pen 70 itself with an electric circuit or battery as described above, and it is possible to input a position in connection with the operation of the input pen 70, so that operability does not deteriorate.

In addition, the number of magnetic bodies and coils in the examples is an example,
Needless to say, it is not limited to this. Furthermore, it has been experimentally confirmed that position detection can be performed with relatively high accuracy if the distance between the coils is approximately 2 to 6 mm. Further, the position specifying magnetic generator is not limited to a permanent magnet, but may be an electromagnet.

FIG. 22 shows another example of the configuration of the position detection circuit, in which a circuit for carrying out the second method of detecting point P is shown.

Initially, the cleared counter 801 is the AND gate 80
The clock pulses generated by the clock pulse oscillator 803 via the clock pulse oscillator 803 are counted. The count value is decoded by a decoder 804, and the multiplexer 31 is switched and controlled. The clock pulse is also sent to a drive signal M 806 via a frequency divider 805. The detected voltage of each coil circuit is passed through the amplifier 32 to the detector 807 and the low-pass filter 8.
08, where it is converted into a continuous signal shown in FIG. 8, and sent to a comparator 809. The comparator 809 compares the signal with the "0" level and outputs a one-shot pulse to the flip-flop 810 when they match.

The flip-flop 810 is reset at the same time as the counter 801 is cleared, and is set upon receiving the one-shot pulse. The output of the flip 70 knob 810 closes the AND gate 802, stops the count of 31 in the counter 801, and is sent to the host computer 812 via the output buffer 7811 to notify the detection of point P. The host computer 812 reads the count value of the counter 801 at that time, and uses the input value from the input bench 20.
Calculate the X coordinate value of Note that a reset signal for the counter 801 and the flip-flop 810 is supplied from the host computer 812 via an input buffer 813.

FIG. 23 shows another embodiment of the present invention. In the figure, 91 and 92 are position detection units in the X direction and Y direction, and 93 and 94 are signal selection circuits for the X and Y directions, which have the same configuration as the position detection unit 10 and the signal selection circuit 30, respectively. (However, the details are omitted in the drawing for simplicity.), and the position detection unit 91.9
2, the respective magnetic bodies are superimposed on each other so as to be orthogonal to the X direction and the Y direction, respectively.

Further, reference numeral 95 designates a position detecting circuit, which is the same as the position detecting circuit 7 except that the position detecting circuit 95 alternately performs position detection in the X direction and the Y direction. It is similar to IO. Therefore, according to this embodiment, the position (coordinates) can be easily detected in two directions, the X direction and the Y direction, and further in the Z direction if necessary. In this case, position detection in the Z direction is performed by the position detection section 91 in the X direction or the Y direction.
It may be determined from any signal from the position detection section 92 in the direction. Note that the configuration of the position specifying magnetic generator may be the same as that of the previous embodiment.

In the embodiments described so far, similar results can be obtained by applying an alternating current to the second coil and detecting the induced voltage generated in the tth coil by detecting the induced voltage from the tth coil. It will be done.

Further, since the position detection device of the present invention only needs to apply a slight steady magnetic field to the position detection section, it can also be used in combination with a flat display panel such as a liquid crystal or a touch panel on the top thereof.

(Effects of the Invention) As explained above, according to the present invention, the mutual inductance between the plurality of coils, which changes based on the specified position of the position specifying magnetic generator, can be adjusted based on the balance of the circuit including the coil. Since it is designed to detect, it is not affected by external induction, level fluctuations, noise, etc., and a large signal can be obtained even if the magnetic force of the magnetic generator is weak. Therefore, the position detection circuit can be improved. It becomes possible to increase the position detection range. In addition, it is possible to detect the position in the height direction, and the height of the magnetic generator for position designation relative to the position detection part can be used as a parameter for timing detection when specifying the position, and the magnetic generator for position designation itself has an electric circuit. It becomes possible to specify a position without providing a battery or a battery, and in conjunction with the operation of the position specifying magnetic generator. In addition, since there is no need to exchange signals between the position specifying magnetic generator and other devices for position detection, it can be cordless. Since the claw is only a few oersteds (Oe), the position specifying magnetic generator is slightly smaller than the position detecting part! ! ! IL
However, the position can be specified even from the back side of the position detection section, and metals other than ferromagnetic materials can also be placed on the input surface. In addition, according to 6, in which the position detection unit is provided in the X direction and the Y direction, it is possible to detect the position in two directions, the X direction and the Y direction, or in addition to these, in the three directions (Z) direction. There are advantages such as:

[Brief explanation of drawings]

The drawings serve to explain the present invention. Fig. 1 is an explanatory diagram showing the main structure of the present invention, Fig. 2 is a characteristic diagram of magnetic bias versus magnetic permeability, and Fig. 3 is a diagram from a magnetic generator for position specification. Figure J shows the magnetic flux applied to the magnetic material, and Figure 4 is a graph showing the amount of magnetic bias applied to the magnetic material by the bar magnet.
Fig. 5 is a graph showing the magnetic permeability of a magnetic material given a magnetic bias by a bar magnet, Fig. 6 is a diagram showing an example of the configuration of a coil circuit in the present invention, and Fig. 7 is a coil of the circuit shown in Fig. 6. Figure 8 is a graph showing changes in the output voltage of the circuit shown in Figure 6, Figure 9 is a diagram showing how to detect the position of zero cross point P, Figure 10 11 is an exploded perspective view showing the specific configuration of the position detection unit 10, and FIG. 11 is a diagram showing how the magnetic plate is manufactured.
Fig. 12 is a perspective view of the conductor plate, Fig. 13 is a view showing the state of magnetic flux around the two coils, Fig. 14 is a perspective view of the main part showing another example of the magnetic plate, and Fig. 15 is the input FIG. 16 is a cross-sectional view showing the specific configuration of the pen, FIG. 16 is its electric circuit diagram, FIG. 17 is a circuit diagram showing the specific configuration of the signal selection circuit, and FIG. 18 is the specific configuration of the position detection circuit. 19 is a polygon diagram showing the signal waveforms at each part in FIG. 18, FIG. 20 is a specific circuit diagram of the drive current source, and FIG. 21 is a cross section showing another example of the actual flow of the input pen. 22 is a circuit block diagram showing another specific configuration of the position detection circuit, and FIG. 23 is a polygon explanatory diagram of another embodiment of the present invention. 10... Position detection unit, 20... Input pen, 30...
- Signal selection circuit, 40... Position detection circuit, 11...
Magnetic material, 12a to 12j...first coil, 13...
・Second coil, 91...X direction position detection section, 92・
...Y direction position detection section. Patent applicant Wacom Co., Ltd. Patent attorney Yoshi 1) Takashi Sei Figure 2 0.5 1. o i, 5 2.0 Magnetic noise (Oe) Fig. 4 Fig. 5 μ X direction marker 1 Fig. 7 x Direction box area Fig. 9 x Direction box Fig. 11 Fig. 12 Fig. 13 Fig. 2C 14 Figure 15 Figure 17 Figure 21 Figure 23 Procedural amendment book form) % formula % 1 Display of the case 1985 Patent Application No. 187899 2 Name of the invention Position detection device 3 Person who makes the correction Relationship with the case Patent Applicant Address: 5-23-4, Washinomiya-cho, Kitakatsushika-gun, Saitama Prefecture Name: Wacom Co., Ltd. Representative: Furu 1) Former Male Agent: 4 Address: 105 Telephone (03) 508-9866
Address: Mr. Hayashi Building, 1-15-11 Toranomon, Minato-ku, Tokyo
Name (6998) Patent Attorney Yoshi 1) Seiko 5 Date of notification of amendment order - November 6, 1985 November 26, 1985 (shipment date) 6. Target of amendment ``Drawings'' 7. Contents of amendment Drawings engraving (no changes in content)

Claims (2)

[Claims] (1) A plurality of elongated magnetic bodies arranged substantially parallel to each other, and a plurality of first coils arranged around the plurality of magnetic bodies at predetermined intervals in a direction perpendicular to the longitudinal direction of the magnetic bodies. ,
a position detection unit including a second coil wound around the plurality of magnetic bodies and the plurality of first coils, and a position specifying magnetism generator that generates a steady magnetic field; a signal selection circuit that combines two of the plurality of first coils so that they are in opposite phases to a second coil and sequentially switches and connects them; The induced voltages induced in each of two of the first coils when an alternating current of a predetermined period is constantly applied to the signal selection circuit are sequentially extracted from the signal selection circuit, or
When an alternating current of a predetermined period is applied to each of two of the coils by switching one after another via a signal selection circuit, induced voltages induced in the second coil are extracted one after another, and from these, the position specifying magnetic field is A position detection device comprising a position detection circuit that determines a specified position on a position detection section using a generator. (2) A plurality of long X-direction magnetic bodies arranged substantially parallel to each other, and a plurality of elongated X-direction magnetic bodies arranged at predetermined intervals in a direction orthogonal to the longitudinal direction of the X-direction magnetic bodies. a first coil in the X direction, and a second coil in the X direction, which is wound almost entirely around the plurality of X direction magnetic bodies and the plurality of an X-direction position detection section provided with the X-direction position detection section, a Y-direction position detection section that has the same configuration as the X-direction position detection section and is overlapped therewith, and a position designation magnetic generator that generates a steady magnetic field; Two of the plurality of first coils in the X direction and Y direction are combined so as to have opposite phases to each other with respect to the second coils in the X direction and Y direction, and these are sequentially switched and connected. direction and Y direction signal selection circuits;
When an alternating current with a predetermined period is constantly applied to the second coil in the X direction and the first coil in the Y direction, the induced voltage is induced in each of the two first coils in the X direction and the Y direction. Take out more sequentially, or the X direction and Y direction
When an alternating current of a predetermined period is applied to two of the first coils in the X and Y directions by switching one after another through the signal selection circuits in the X and Y directions, the second coils in the X and Y directions are applied.
A position detecting device comprising a position detecting circuit which sequentially extracts induced voltages induced in the coil and determines the specified position on the position detecting section in the X direction and Y direction by the position specifying magnetic generator.