JPS59125479A - Coordinate input device - Google Patents

Abstract

PURPOSE:To improve the reliability of a coordinate input device by detecting the pressure of a pen with two planar electrodes and a flexible insulator held between these electrodes, and inputting only the position information obtained when the pen has sufficiently large pressure. CONSTITUTION:A resistance film 24 is attached to the lower side of a flexible insulated plate 23, and electrodes 25 and 26 are provided at the two counter sides of the plate 23. Thus the 1st detecting plate 21 is formed. Furthermore the 2nd detecting plate 31 is set to hold a pressure-sensitive and conductive rubber sheet 32 with the plate 21. The plate 31 is formed by attaching a resistance film 28 to the upper side of a flexible insulated plate 27 together with electrodes 29 and 30 provided at two sides of the plate 27. A planar electrode 33 having flexibility, a pressure-sensitive and conductive rubber sheet 34 having flexibility and a planar electrode 35 are set under the plate 31. The pressure of a pen 22 is detected by the electrodes 33 and 35 and the sheet 35. Then the position information is decided correct only when the pressure of the pen 22 is sufficiently large.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a coordinate system for inputting hand-black characters S.

Conventional Structures and Problems Generally, coordinate input devices detect the coordinate position of a pen in order to input handwritten characters. The detected character information is sent to a computer or the like and displayed on a display device such as a CRT.

In order to know the position of a pen for handwriting input, conventionally known coordinate input devices are equipped with detection plates that detect the coordinate position of 1° in the X-axis direction and the Y-axis direction, and these are overlapped. A system in which the pen's position coordinates are determined by inductively or capacitively coupling between the sensing plate and the pen, so that the pen receives the position tZ-f signal from the sensing plate, or vice versa, by receiving the signal from the pen on the sensing plate. There is.

In addition, there is another conventionally known coordinate system using a resistive plate with uniformly distributed resistance values. A conventional configuration using this resistance plate will be described below with reference to the drawings.

FIG. 1 is a block diagram of a conventional coordinate input device using this resistance plate. 1, a resistive film 4 with a uniform resistance value is attached to the bottom surface of an insulating plate 3 which is flexible so that the input point is deformed downward, and electrodes 5 are attached on the two opposite sides. , 6 is provided. Below the first sensing plate 1, a resistive film 8 with a uniformly distributed resistance value is attached to the upper surface of the insulating plate 7, and electrodes 9 are placed on two opposing sides at different positions from the first sensing plate 1. A second detection plate 11 provided with a pressure-sensitive conductive rubber band 12 is disposed facing each other with a pressure-sensitive conductive rubber band 12 in between. The pressure-sensitive conductive rubber band 12 is a well-known material and is usually considered to be an insulator, but when a pressure of more than a predetermined value is applied in the thickness direction, the resistance value near the point of application of the pressure changes to the pressure shown in Figure 2. - As shown in the resistance characteristic diagram, it is a type of 7 in which the resistance value decreases rapidly and then returns to its original value when the pressure is removed.
・Possesses inochi-like properties. Now, if a predetermined pressure or more is applied to any point on the first detection plate 1 by Ben 2, the above pressure will be applied to the pressure-sensitive conductive rubber notebook because the first detection plate 1 has flexibility. 12, the first sensing plate 1 and the second sensing plate 11 at the pen 20 input point are electrically energized.

At this time, for example, if a constant voltage is applied between electrodes 5 and 6, a divided voltage corresponding to the position of Ben 2 in the X-axis direction is derived at electrode 9, and conversely, a constant voltage is applied between electrodes 9 and 10. If this is done, a divided voltage corresponding to the position of the pen 2 in the Y-axis direction is derived from the electrode 5, so that the coordinates of the input position of the pen 20 can be known.

A constant voltage is applied between these series of electrodes, and a divided voltage is derived from the other electrodes.
The operation of alternately switching in the axial direction is performed by the position detection circuit 13. The trench position detection circuit 13 converts the input divided voltage into analog-to-digital data and outputs it as position information. By inputting this digitalized (S)' and @ information into the arithmetic unit and performing simple calculations, it is possible to know the coordinates of the pen 20 input position, and furthermore, the characters input by Ben 2 can be converted to CFf. It can be displayed on any display device.

In the conventional example described above, a pressure-sensitive conductive rubber sheet is used as the nullifier for the two detection plates, and there is a transition region C between the region A and the conductor region I. Unfortunately, in the conventional coordinate input device shown in Fig. 1, when pressure is applied with a bend, the divided voltage indicating the position information is not stable in this transient region C, and the position is detected when this pressure is not applied sufficiently. Once the circuit has obtained position information, it has the disadvantage of giving incorrect coordinate values.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a coordinate input device that eliminates errors in IA information, which solves the above-mentioned conventional problems.

Structure of the Invention The coordinate system (7) of the present invention consists of a part that detects the coordinate position of a structure in which two flexible detection plates face each other with a pressure-sensitive conductive rubber sheet in between, and a part below the part that detects the coordinate position. It consists of a part that detects Ben input with a structure in which two opposing planar electrodes sandwich a flexible insulator between them, and a position detection circuit detects the conduction of the two planar electrodes. This is to control the inflow J from the detection plate.

DESCRIPTION OF EMBODIMENTS Hereinafter, one embodiment of the present invention will be explained in detail using drawings.
-Explain.

FIG. 3 is a schematic diagram of a coordinate input device showing an embodiment of the present invention. 21 attaches a resistive film 24 uniformly distributed so that the resistance value changes regularly on the lower surface of the insulating plate 23, which has flexibility so that the input point is deformed downward with the bend 22, and then This is a first sensing plate provided with electrodes 25 and 26 on its sides. Below the first detection plate 21,
A uniformly distributed resistive film 28 is attached to the upper surface of the flexible insulating plate 27 so that the resistance value changes regularly, and furthermore, electrodes 2 are attached on two opposing sides at a different position from the first sensing plate 21. ．． The second detection plate 31 provided with q, 30 is connected to the first
The pressure-sensitive conductive rubber sheets 32 are placed facing each other. The above configuration constitutes a part that detects the coordinate position, and up to this point it is the same j4! as the conventional example shown in FIG.
>It is made of

Below the second sensing plate 31 is a first flexible flat electrode 33, and further below that is a flexible second pressure-sensitive conductive rubber sheet 34, which is an insulator. Further below, second plane electrodes 3S are provided facing each other.

In the above configuration, the pen 22 is
For example, when the input is made at a pressure higher than a predetermined value, the electrode 25.2
If a constant voltage is applied between electrodes 29 and 30 by the position detecting device 36, a divided voltage corresponding to the position of the pen 22 in the X-axis direction is derived to the electrode 29, and conversely, a constant voltage is applied to the electrode 29 by the position detecting device 36 between the electrodes 29 and 30. If voltage is applied, the pen 2 will be connected to the electrode 25.
A divided voltage corresponding to the position in the Y-axis direction of 2 is derived.

At this time, when the pen 220 is in the input position, the pressure of the pen 22- is also applied to the second pressure-sensitive conductive rubber sheet 34 via the first plane electrode 33, and the plane electrodes 33 and 35 are electrically connected. Here, in order to eliminate errors in positional information due to transient areas of the pressure-sensitive conductive rubber sheet, the pressure applied by the pen 22 must be large enough to ensure that the pressure point of the tenth pressure-sensitive conductive rubber sheet 32 is in the conductor area in FIG. must be present. Therefore, in the coordinate input device of the present invention, the pressure of the pen 22 is also applied to the second pressure-sensitive conductive rubber sheet 34, and the state of conduction between the planar electrodes 33.degree. 35 is monitored by the position detection device 36.

Then, by applying pressure with the pen 22, the planar electrode 33.
Valid only the position information input from the electric i2S or two electrodes when the resistance value between 35 and 35 is below a predetermined value,
Analog to digital conversion and output to arithmetic device. By doing this, when the point of the first pressure-sensitive conductive rubber sheet 32- to which the pen 22 receives pressure is in the insulating region & or the transition region C shown in FIG. 2, no position information is input and the pen pressure is Errors in position information caused by insufficient position information are eliminated, and information on the correct coordinate position of the pen can be sent to the computing device.

In addition, if the second pressure-sensitive conductive rubber sheet 3+ is made of a material whose resistance change is less sensitive to pressure than the first pressure-sensitive conductive rubber sheet 3λ, when pressure is applied by the pen 22, First pressure-sensitive conductor 1! J-Gomshi 1-32
The second pressure-sensitive conductive rubber sheet 34 can transmit the correct coordinate position to the calculation device by the position detection device 3B only after the conduction i☆#(i′ information becomes the correct value. Conversely, when removing the pressure from the pen 22, the second pressure-sensitive conductive rubber sheet 34 becomes non-conductive and input is inhibited by the position detection device 3B while the position information shows the correct value. Since the first pressure-sensitive conductive rubber sheet 32 becomes non-conductive for the first time, the risk of inputting erroneous positional information to the arithmetic device can be further reduced.

In addition, in the embodiment, the first and second detection plates 2 detect the partial pressure due to the resistance at the input position separately in the X-axis direction and the Y-axis direction.
1 and 31, the present invention is configured to transmit the pressure of two flexible sensing plates to the flat electrode 33, so other sensing plates may be used as long as they are flexible. Furthermore, the flexible insulator does not need to be solid, and may be air, oil, or the like.

Effects of the Invention As described above, the coordinate human-powered device of the present invention detects pen pressure using two planar electrodes and a flexible insulator sandwiched between them, and detects only the position information of the sticker where the pen pressure is sufficiently large. By determining the position 1 pin 1' as correct information by the position 1 pin 1' detection device, it is possible to eliminate errors in position information due to insufficient pressure on the pressure-sensitive conductive rubber sheet, and provide a highly reliable coordinate human-powered device at l, +yt. can do.

[Brief explanation of the drawing]

Figure 1 shows a conventional coordinate system.
The figure is a pressure-resistance characteristic diagram of the pressure-sensitive conductive rubber sheet, and FIG. 3 is a 1° 17j diagram of the coordinate input device showing the one-length flow side of the present invention. 21.31...detection plate, 32...first pressure-sensitive conductive rubber sheet, 33.35...plane electrode,
34... Flexible insulator (second pressure-sensitive conductive rubber sheet), 36... Position detection device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure Vise Figure 3

Claims (3)

[Claims] (1) The first sandwiched between two flexible sensing plates
a pressure-sensitive conductive rubber sheet, two flat electrodes arranged on the sensing plate, at least one of which is flexible on the sensing plate side, and two flat electrodes arranged between the two flat electrodes. A coordinate input device comprising a flexible insulator and a position detection device that monitors conduction between the two planar electrodes and controls input from the detection plate. (2) The coordinate input device according to claim 1, wherein the flexible insulator is a second pressure-sensitive conductive rubber sheet. (3) The coordinate input device according to claim 2, wherein the second pressure-sensitive conductive rubber sheet has a pressure 18 degrees lower than that of the first pressure-sensitive conductive rubber sheet.