JPH0519938A - Wireless digitizer - Google Patents

Abstract

PURPOSE:To easily charge a second-order battery by using the second-order battery for a power source for cursor and switching a normal measuring mode and the charging mode of the second-order battery by a time division system. CONSTITUTION:In the measuring mode, mode changeover switches (MS) 18 and 19 are connected to an upper contact, the voltage of a second-order battery 23 is supplied to loads 12-15, a signal frequency current amplified by an amplifier circuit 15 is supplied to a cursor coil (KC) 10, and a current to flow to the KC 10 is increased by tuning a capacitor 16. Then, by executing the signal processing of a voltage induced at the X winding coil or Y winding coil of a grid plate, a coordinate position is decided. In the charging mode, the MS 18 is connected to a lower contact, a power supply frequency AC voltage induced at the KC 10 is boosted by tuning a capacitor 17 and impressed to a rectifier circuit, and the second-order battery 23 is charged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate position detecting device for measuring the plane coordinate position of a cursor on a grid plate based on electromagnetic induction between the grid plate and a cursor placed on the grid plate. In the above, the present invention relates to a wireless digitizer which does not require a cable for connecting a cursor and a grid plate.

[0002]

2. Description of the Related Art As a prior art of the present invention, a patent application filed by the same applicant as the applicant of the present application, Japanese Patent Application No. 250241/1990.
No. “Coordinate position measuring device”, Japanese Patent Application No. 2-254339 “Coordinate position measuring device” and Japanese Patent Application No. 2-272185 “Coordinate position measuring device” (hereinafter collectively referred to as prior application)
There is. A plurality of X windings formed by a conductor whose longitudinal direction is parallel to the X axis are arranged parallel to each other on the XY plane defined with respect to the X axis and the Y axis which are orthogonal to each other at the same interval in the Y axis direction. X winding grid plate and a plurality of Y windings formed by a conductor whose longitudinal direction is parallel to the Y axis are arranged in parallel with each other at the same interval in the X axis direction.
Winding grid plates, a cursor that is placed on these grid plates and that generates an electromagnetic field that couples to the windings on the grid plates, and a voltage that is induced in the windings by the electromagnetic field from this cursor A coordinate position detecting device having a signal processing device that performs signal processing on the generated voltage and calculates a plane coordinate position of the cursor on the grid plate is well known in the related art.

The device according to the prior application is a device for determining the coordinate position by applying a signal current to the cursor and processing the voltage induced on the X winding or the Y winding of the grid plate. As a power source, a power source voltage induced in a power source coupling coil provided on the cursor is rectified by a power source alternating current flowing through a power source grid plate and used.

[0004]

The problem to be solved is that it is difficult for the conventional wireless digitizer to generate a magnetic field having a constant amplitude on the entire surface of the grid plate. Further, since it is necessary to pass an alternating current having a power source frequency through the conductors of the entire grid plate, there is a problem that power consumption increases and unnecessary radiation increases.

The present invention has been made to solve the above problems, and an object thereof is to solve the above problems in the conventional apparatus and to obtain a wireless digitizer which can easily supply power.

[0006]

A wireless digitizer according to the present invention is characterized by using a secondary battery as a power source for a cursor and switching between a normal measurement mode and a charging mode of the secondary battery in a time division system. There is. That is,
In the charging mode, a cursor coil that allows a current having a signal frequency to flow in the measurement mode is connected to induce an AC voltage, and the induced AC voltage is rectified to charge the secondary battery. In addition, since the position of the cursor coil is known from the measurement in the measurement mode in advance on the side of the signal processing device, it is necessary to connect so that the AC current for power supply may flow through the X winding and the Y winding closest to the position. And

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing each part of a cursor 1 in one embodiment of the present invention, and FIG. 2 is a block diagram showing each part other than the cursor 1. In these figures, 10 is a cursor coil and 11 is a cursor switch group. , 12 is a code generation circuit, 13 is a signal frequency voltage generation circuit, 14 is a modulation circuit, 15 is an amplification circuit, 16 and 17 are tuning capacitors, 18 and 19 are cursor mode changeover switches, 20 is a rectifier, and 21 is charge limitation. A resistor, 22 is a smoothing capacitor, and 23 is a secondary battery.

In FIG. 2, 3 is an X winding, 4 is a Y winding, 5 is an X winding scanner, 6 is a Y winding scanner, 7 is a signal processing device, 51 is an X winding mode changeover switch, 61 is a Y winding mode selector switch, 5
2, 53, 62 and 63 are amplifier circuits, respectively,
Shows a cursor coil as in FIG.

Next, the operation will be described. In FIG. 1, the state in which the mode changeover switches 18 and 19 are connected to the upper contacts as shown in the figure is the measurement mode, and the voltage from the secondary battery 23 is the load 12, 13, 14,
The signal frequency current supplied to the amplifier 15 and amplified by the amplifier circuit 15 is supplied to the cursor coil 10, but the current flowing through the cursor coil 10 increases in synchronization with the capacitor 16.

The mode switches 51 and 61 shown in FIG.
The X winding scanner 5 is connected to the amplifier circuit 52 by sequentially switching the voltage induced in each X winding in the order of arrangement of the X windings. The output is processed in the signal processing device 7, and the accurate coordinate position of the center position of the cursor coil 10 in the X-axis direction is calculated from the change in the amplitude corresponding to each X winding.

Similarly, the Y-winding scanner 6 sequentially switches the voltages induced in the respective Y-windings in the order of arrangement of the Y-windings and connects them to the amplifier circuit 62. In addition, the cursor switch group 11
The technique for operating the to notify the signal processing device 7 of the information regarding the attribute of the measurement target point is as described in detail in the previous application. Further, for convenience of explanation, the X winding scanner 5, the Y winding scanner 6, the mode changeover switches 51 and 61, and the amplifier circuits 52, 53, 62 and 63 are shown separately from the signal processing device 7, but all of them or Part of the signal processing device 7 may be part of the signal processing device 7.

When the measurement mode is terminated as described above and then the charging mode is entered, the highest voltage in the measurement mode is applied to the X winding 3 and Y which are induced in the cursor coil 10.
The winding 4 is an X winding scanner 5, and a Y winding scanner 6
The X winding scanner 5 and the Y winding scanner 6 are stopped at a position where they are connected to the output point of the. When the mode changeover switches 51 and 61 are connected to the right contacts respectively, the power supply frequency AC voltage from the signal processing device 7 is amplified by the amplifier circuits 53 and 63, respectively, and the cursor coil 1
Is supplied to the X winding 3 and the Y winding 4 immediately below 0,
A strong magnetic field is generated at the position of the cursor coil 10.

In the charging mode, the change-over switch 18 of FIG. 1 is connected to the lower contact, and the power supply frequency AC voltage induced in the cursor coil 10 is boosted in synchronization with the capacitor 17 and added to the rectifying circuit. Secondary battery 23
To charge.

As is clear from the above description, all the mode changeover switches 18, 51 and 61 must be operated in conjunction with each other. Since the cursor 1 is manually operated by a human, it is easy to configure the switches 18 and 19 into switches that interlock with the manual movement of the cursor 1, and the switches 18 and 19 are interlocked with the signal processing device 7. Radio wave,
It is also easy to send a signal via light, a sound wave, etc., and automatically switch the mode changeover switches 51, 61 by this signal. When the secondary battery 23 having an appropriate capacity is used, after the required measurement is completed, the cursor coil 10 is placed at a predetermined position for a charging cycle, and the X winding 3 and the Y winding at that position are set. It is also possible to charge the wire 4 by passing a current having a power supply frequency.

Further, when it is necessary to charge the battery for a short time, when the signal processing device 7 finishes the voltage measurement and enters the calculation mode for calculating the coordinate position using the measured value, The calculation mode period may be the charging mode period. However, in this case, it is necessary to operate the mode switch 18 of the cursor from the signal processing device 7, and some means is required to prevent the cursor 1 from being accidentally moved during the charging mode.

[0016]

As described above, the cordless digitizer of the present invention uses the secondary battery as the cursor power source,
A power supply system that can easily charge the secondary battery is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing each part of a cursor according to an embodiment of the present invention.

FIG. 2 is a block diagram showing each part other than a cursor according to an embodiment of the present invention.

[Explanation of symbols]

 1 Cursor 3 X Winding 4 Y Winding 5 X Winding Scanner 6 Y Winding Scanner 7 Signal Processor 10 Cursor Coil 18 Cursor Mode Changeover Switch 19 Cursor Mode Changeover Switch 23 Secondary Battery 51 X Winding Mode Changeover Switch 61 Y Winding mode selector switch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Konobu Sakurada 503-10 Shinanomachi, Totsuka-ku, Yokohama, Kanagawa Prefecture Graphtec Co., Ltd.

Claims (1)

Claim: What is claimed is: 1. A plurality of X windings formed by a conductor whose longitudinal direction is parallel to the X axis are parallel to each other on an XY plane defined with respect to the X axis and the Y axis which are orthogonal to each other. An X-winding grid plate arranged at equal intervals in the Y-axis direction,
A Y-winding grid plate in which a plurality of Y-windings formed of a conductor whose longitudinal direction is parallel to the Y-axis are arranged in parallel to each other at the same intervals in the X-axis direction, and mounted on these grid plates. A cursor for generating an electromagnetic field coupled to a winding on the grid plate, and a voltage induced on the winding by the electromagnetic field from the cursor is input, and signal processing is performed on the input voltage, and the grid plate of the cursor is input. In a wireless digitizer having a signal processing device for calculating a plane coordinate position on the above, the cursor is a code generation circuit, a cursor switch group for inputting a signal for determining a code generated from the code generation circuit, A signal voltage generation circuit that generates a voltage of a predetermined signal frequency, and a modulation circuit that modulates the output of the signal voltage generation circuit with the output of the code generation circuit, A code generator circuit, the signal voltage generator circuit, a secondary battery for supplying power to the modulator circuit, and the output of the modulator circuit in the measurement mode is connected to the cursor coil, and induced in the cursor coil in the charge mode. And a cursor mode changeover switch for connecting an AC voltage as a power source of a charging circuit for charging the secondary battery, wherein the signal processing device sequentially applies the signal voltage induced in each winding of the plurality of X windings. An X winding scanner that is switched to connect to the voltage measuring device, a Y winding scanner that sequentially switches the signal voltages induced in the plurality of Y windings to connect to the voltage measuring device, and the above in the measurement mode. An X winding connecting the output point of the X winding scanner to a voltage measuring device and connecting the output point of the X winding scanner to an AC voltage for power supply in the charging mode. Mode switch and the output point of the Y winding scanner is connected to the voltage measuring device in the measurement mode, and the output point of the Y winding scanner is connected to the AC voltage for the power supply in the charging mode. A Y winding mode changeover switch, and when the cursor is not used for coordinate position determination and is in a stationary state, the cursor mode changeover switch, the X winding mode changeover switch, the Y
The winding mode changeover switches are both connected in the charging mode, the X winding and the Y winding closest to the coordinate position of the cursor at that time are selected, and the alternating current for power supply is supplied to both the selected windings. A wireless digitizer featuring.