JPH0546575B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for determining coordinate positions on a plane.

[Conventional technology]

As a prior art in this field, there is an invention (hereinafter referred to as "prior art") disclosed as an automatic coordinate positioning device in Japanese Patent Publication No. 49-44540. FIG. 5 is a block diagram showing the configuration of the prior art. In the figure, 1 is a sine wave voltage generating circuit, which generates a sine wave with a frequency of, for example, 3 kHz. A cursor coil 2 generates, for example, an alternating magnetic field of 3 kHz centered on the central axis of the cursor coil 2 by the current from the sine wave voltage generating circuit 1. A reference phase signal line 3 transmits a voltage indicating the reference phase of the 3kHz sine wave voltage generated by the sine wave generating circuit 1. 4 and 5 are amplifiers, 6 is a 90° phase shifter, 7 is an analog adder, 8 is a phase measurement circuit, and 9 is a y-axis signal processing/phase measurement circuit. , 8 includes one set of circuits with the same configuration as . Reference numeral 11 denotes a lattice device, which is made up of four laminated insulating substrates each having a plane in which a conductor is formed in a lattice shape, in which a voltage is induced by the electromagnetic induction of the alternating magnetic field generated by the cursor coil 2. It is formed. Although the thickness of these insulating substrates is extremely thin, the thickness of the insulating substrate constituting the grating device 11 is shown enlarged in FIG. 5 for convenience of explanation. In each figure other than FIG. 5, the thickness of the insulating substrate is shown enlarged.

FIG. 6 is a plan view showing the lattice shape of the conductor on the two insulating substrates in the lattice device 11 of FIG. A meandering conductor grid 11b indicated by dotted lines is formed on the second insulating substrate. 2 is a circular cursor coil like 2 in FIG. The longer direction of the conductor grid shown in FIG. 6 is the y-axis, and the direction perpendicular thereto is the x-axis. In the example shown in FIG.
1a is parallel conductors that are arranged parallel to the y-axis direction and spaced apart by D/2 in the x-axis direction, and the ends of adjacent parallel conductors are connected alternately at both ends to connect all the conductor grids that belong to one conductor grid. It consists of end turns for connecting conductors in series, and its pitch is D. The conductor grid 11b is also configured similarly to the conductor grid 11a, but with respect to the conductor grid 11a, +x
The conductors are arranged shifted by D/4 in the direction of .

Consider the voltage induced in the conductor grid 11a when an alternating current of frequency f is passed through the cursor coil 2. The center point of the cursor coil 2 is the conductor grid 11a
directly above a conductor parallel to the y-axis, the voltage induced in that conductor from the right half of coil 2 is the same as the voltage induced in that conductor from the left half of coil 2, and their directions are mutual. Since they are in opposite directions, they cancel each other out and become zero. When the center point of the cursor coil 2 is placed at the center of two adjacent conductors of the conductor grid 11a, the voltage induced from the right half of the coil 2 to the right conductor and the voltage induced from the left half of the coil 2 to the left conductor The induced voltages are in opposite directions, but since the two voltages are connected through the end turn so that they are added together, the conductor grid 11
The induced voltage at a becomes maximum.

Therefore, as shown in FIG.
If the position of one conductor of 1a is x=0, the composite voltage V _A induced in the conductor grid 11a is V _A =V _M sin2πx/Dsin2πft (1). Similarly, the composite voltage V _B induced in the conductor grid 11b is V _B =V _M sin2π(x-D/4)/Dsin2πft = -V _M sin2πx/Dsin2πft (2). However, V _M represents the maximum amplitude of the induced voltage.

The voltage V _BQ obtained by shifting the phase of the voltage V _B by 90° is V _BQ = V _M sin2πx/D cos2πft ...(3), and V _R = V _A + V _BQ = V _M cos (2πft−2πx/D)...(4) becomes.

That is, the outputs of amplifiers 4 and 5 in FIG. 5 are expressed by formulas (1) and (2), and the output of 90° phase shifter 6 is expressed by formula
In (3), the output of the analog adder 7 can be expressed by equation (4). The voltage on the reference phase signal line 3 is V _Rcps
If 2πft, the phase difference 2πx/D is measured by the phase measuring circuit 8, and since D is known, x can be calculated.

Similarly, in the y-axis signal processing/phase measurement circuit 9, the coordinate position of the center point of the cursor coil 3 in the y direction can be calculated.

[Problem that the invention seeks to solve]

Since the conventional device is constructed as described above, it has been difficult to eliminate the so-called edge effect.

In other words, as the position of the cursor coil 2 approaches the end turn, the voltage induced at the end turn increases and is added as an error voltage to the voltages expressed by equations (1) and (2), resulting in the difference in equation (4). An error occurs in the phase difference. Conventional devices are provided with a compensating conductor to eliminate the edge effect, but providing this compensating conductor complicates the shape of the conductor element on the insulating substrate, and it is difficult to fully eliminate the edge effect. The problem was that it could not be erased immediately.

This invention was made to solve the above problems, and aims to provide a coordinate positioning device that does not require a compensation conductor to eliminate the edge effect and does not generate the edge effect. The purpose is

[Means for solving problems]

In this invention, the ends of the parallel conductors are alternately connected at both ends by end turns to avoid connecting all the conductors belonging to one conductor grid in series to form a meandering conductor grid, and each parallel conductor We decided to extract the voltages induced in the conductors separately and add them together using an operational amplifier, thereby omitting the end turns. In addition, in order to prevent the voltage induced in the current collecting conductor that collects the voltage for addition and connects it to the input point of the operational amplifier from being input as an error,
The connection was made in such a way that the induced voltages of the current collecting conductors where the same voltage is induced cancel each other out.

[Effect]

Since there are no end turns, no edge effect occurs and the voltages induced in the current collecting conductors cancel each other out.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention, in which the same symbols as in FIG. 5 indicate the same or corresponding parts, 41 and 51 are operational amplifiers, 1
00 is the grating device of this invention.

In the lattice device 100, one insulating substrate in the conventional lattice device 11 is divided into two insulating substrates, so that the lattice device 11 in FIG. 5 is constructed by laminating four insulating substrates. If formed, the grating device 100 of the present invention is formed by laminating eight insulating substrates.

FIG. 2 is an exploded perspective view showing the lamination of insulating substrates in the grating device 100 of FIG. 1, and FIGS.
The figure is a plan view of each insulating substrate shown in FIG. 2 developed and showing its conductor lattice. Figure 1, Figure 2, Figure 3
Figure, 10, 20, 30, 40, 5 through Figure 4
0, 60, 70, 80 are each insulating substrate, 116,
216, 316, 416, 516, 616, 71
6,816,117,217,317,417,
517, 617, 717, 817 are connection terminals, 101, 102, 103, 104, 10, respectively.
5,201,202,...301,302,...40
1,402,...501,502,...601,60
2,...701,702,...801,802,... are conductors, respectively, 106,107,206,20
7,306,307,406,407,506,
507,606,607,706,707,80
6,807 are current collecting conductors, 108,10 respectively
9,110,111,112,208,...,30
8,...,408,...,508,...,608,...,
708, . . . , 808, . . . are input resistors inserted in series with the respective conductors and used to add the voltages induced in the conductors by the operational amplifier. Therefore, it is necessary that all these resistors have the same resistance value.

The x and y orthogonal coordinate axes fixed on the plane of the insulating substrate are determined as shown in FIGS. 3 and 4. By the way, FIG. 3 and FIG. 4 are the same if the x-axis and y-axis are exchanged, so we will explain FIG. Description of the circuit shown in FIG. 4 will be omitted.

For convenience of explanation, substrates 10, 20, 30, 40
are called first, second, third, and _fourth substrates, and these substrates are respectively connected to a current collecting conductor (referred to as a first conductor, for example, a conductor 10
6), a current collecting conductor (referred to as a second conductor, for example, conductor 107) parallel to the x-axis at the position y= _ys ,
They are parallel to the y-axis and arranged with a pitch interval D in the x-axis direction, with the first conductor 106 and the second conductor 1 at both ends.
Multiple parallel conductors (for example, 1
01 to 105) and a resistor inserted into each conductor (for example, 108 to 11
2).

Furthermore, when the position of the conductor grid on the first substrate 10 is used as a reference, the positions of the second, third, and fourth substrates 20, 3
The positions of the conductor grids on 0 and 40 are shifted in the +x direction by D/2, D/4, and 3D/4, respectively.

As shown in FIG. 1, the first conductor 106 of the first substrate 10 and the second conductor 207 of the second substrate 20
The connection point (the short-circuit point between the connection terminals 116 and 217) is connected to the inverting input terminal of the operational amplifier 4, and the second conductor 107 of the first substrate 10 and the first conductor 206 of the second substrate 20 are connected. points (connection terminals 117 and 21
6) to the non-inverting input terminal of the operational amplifier 4, conductors 101, 102, 103, 10
From the sum of the voltages induced on the conductor 20
The voltage obtained by subtracting the sum of the voltages induced in 1, 202, . . . becomes the output of the operational amplifier 41. That is,
From the conductor grid in which the substrates 10 and 20 are stacked, the sixth
A voltage corresponding to the conductor grid 11a in the figure can be obtained, and when the substrates 10 and 20 are stacked, no end turns are required, so no edge effect occurs. Also, the conductor 1 is controlled by the cursor coil 2.
The voltages induced in conductors 107 and 207 are equal and applied in opposite directions, and the voltages induced in conductors 107 and 207 are equal and applied in opposite directions, so no error occurs due to the current collecting conductor. .

Similarly, the voltage shown in equation (2) can be obtained from the conductor grids on the substrates 30 and 40 by the operational amplifier 51.

Since the circuits after the operational amplifiers 41 and 51 operate in the same manner as the circuits indicated by the same reference numerals in FIG. 5, their explanation will be omitted. Furthermore, the substrates 50, 60, 70, 80
The operation of determining the position of the cursor coil 2 in the y direction by the y-axis signal processing/phase measuring circuit 9 having the same circuit configuration as the conductor grids 41, 51, 6, 7, and 8 from the upper conductor grid is performed by the substrates 10 to 40. This operation is similar to the operation of determining the x-direction position of the cursor coil 2 from the conductor grid above, so its explanation will be omitted.

By the way, in many cases, the device of this invention
As shown in the figure, it is equipped with 8 insulating substrates, but when using it for the purpose of determining position on a straight line, for example, it is necessary to have only the parts necessary for determining the position in the x-axis direction. Therefore, a configuration in which the substrates 50, 60, 70, 80 and the y-axis signal processing/phase measurement circuit 9 are omitted in the first embodiment is also included as an apparatus of the present invention.

In addition, in FIGS. 3 and 4, the resistors 108, 1
09, . . . are shown separately from the conductors 101, 102, . . . However, if the conductors 101, 102, .

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain a coordinate position determining device in which edge effects can be completely eliminated using a simple circuit.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is an exploded perspective view showing the stacking of insulating substrates in the grating device of FIG. 1, and FIGS. 3 and 4 are each of the components shown in FIG. FIG. 5 is a block diagram showing the configuration of the prior art; FIG. 6 is a plan view showing the conductor lattice on the two insulating substrates in the lattice device of FIG. 5. A plan view showing the shape of. 1... Sine wave voltage generation circuit, 2... Cursor coil, 3... Reference phase signal line, 41, 51... Operational amplifier, respectively, 6... 90° phase shifter, 7... Adder, 10, 20 , 30, 40...first, second,
Third and fourth insulating substrates, 106, 206, 30
6,406...first conductor, 107,2 respectively
07, 307, 407...each second conductor,
100...Grid device. The same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A lattice device formed by laminating a plurality of insulating substrates each having a plane in which a conductor in which a voltage is induced by electromagnetic induction is formed in a lattice shape, and a cursor coil placed on the cursor coil, the coordinates for determining the coordinate position of the cursor coil on the plane of the lattice device by passing an alternating current through the cursor coil and processing the voltage induced in the conductor of the lattice device; In the positioning device, when the axes of rectangular coordinates fixed on the plane of the grating device are the x-axis and y-axis, a substrate related to coordinate position determination in the x-axis direction among the plurality of insulating substrates of the grating device; is composed of four substrates, first, second, third, and fourth, and each of these four substrates has a first conductor parallel to the x-axis at a position of y=y _e , and a conductor parallel to the x-axis at a position of y=y _s. and a second conductor parallel to the x-axis at the position of The first substrate includes a conductor grid made up of a plurality of parallel conductors, and a resistor inserted into each conductor as an input resistance when adding voltages induced in each conductor of the conductor grid by an operational amplifier. With the upper conductor grid as a reference, the positions of the conductor grids on the second, third, and fourth substrates are +
A first connection that connects the first conductor of the first substrate and the second conductor of the second substrate, which are arranged to be shifted by D/2, D/4, and 3D/4 in the x direction, respectively. From the voltage at the point, the voltage at a second connection point connecting the second conductor of the first substrate and the first conductor of the second substrate is subtracted by the first operational amplifier; From the voltage at the third connection point connecting the first conductor of the substrate and the second conductor of the fourth substrate, the voltage of the second conductor of the third substrate and the first conductor of the fourth substrate is calculated. A second operational amplifier subtracts the voltage at a fourth connection point that connects the conductor of A coordinate position determination device characterized in that the position of the cursor coil on the x-axis is calculated by measuring the phase of the combined voltage added in the coordinate position determination device.