JPH07160402A - Analog touch switch - Google Patents

Abstract

PURPOSE:To output an alarm, etc., by applying a 2nd specific voltage between adjacent electrodes and detecting a current value between the adjacent electrodes, and comparing it with respective estimated current values found from respective coordinate data and deciding multiple depression when there is a difference exceeding a permissible value. CONSTITUTION:When the touch switch is pressed, coordinate data between opposite electrodes 12 and 13 are found for the depression point. If multiple depression is done, coordinate data on the center of gravity are outputted. The contact surface between resistance films 10, however, increases, so the current value increases and when the current value between the adjacent electrodes which are actually measured exceeds an range of an error based upon an estimated value of a current which is estimated from the original coordinate data and flows between the adjacent electrodes, multiple depression is decided as to the coordinate data. For the detection of the current value, current detection resistances R1 and R2 are used in series with a drive circuit 200 which applies the voltage to the electrodes, and the current value is detected in the form of a voltage value and compared with data on a voltage value corresponding to the estimated current value to generate a signal in case of the multiple depression.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analog touch switch using a panel switch plate made of a resistance film or the like, which is used as an input interface on a display or the like.

[0002]

2. Description of the Related Art Conventionally, in an analog touch panel switch which is formed by forming a uniform resistive film on the surface of a rectangular flat plate and arranging the two resistors to face each other in a non-contact state, the contact point when the touch panel is pressed is , The applied voltage in two orthogonal directions is alternately applied, the potential at that point is read and obtained as coordinate data, and the position is detected. Since the position can be detected, this touch panel can configure an input interface as an input device on a display, and is often used as a simple input means of a computer.

[0003]

However, this touch panel plate is composed of a continuous resistance film, and since the coordinate value takes an analog value, the pressing operation is operated by a human hand, so one place is required. Even if you intend to press the button, you may have to press several points at the same time. In the case of multiple pressing, as shown in the equivalent circuit diagram of FIG. 3, the potential of the center of gravity that is pressed multiple times is detected, and the data becomes as if it were the coordinates pressed by one point. There is a possibility that the coordinate data may be different from the intended point.

Therefore, an object of the present invention is to provide an analog touch switch having a multiple push detection function so that a warning can be issued when multiple pushes are made.

[0005]

In order to solve the above-mentioned problems, the structure of the present invention has two flexible members having a rectangular homogeneous resistance film on the surface and arranged so that the resistance films face each other in a non-contact manner. Touch panels A and B, and electrodes a and b on the two opposite sides of A.
However, the B is provided with electrodes c and d on two opposite sides at positions different from the A, and between the electrodes a and b, and cd.
A drive control unit that alternately applies a predetermined voltage between the touch panel A and B is measured by a voltage measuring unit connected to the touch panel A or B to measure the potential of the touched point when any one of the touch panels A and B is touched. An analog touch switch including a touch detection unit that obtains coordinate data of the pressed point and a data processing unit that processes the obtained coordinate data is provided between the adjacent electrodes ac, or b-d. A second predetermined voltage is applied in between to detect the current value between each time when the button is pressed, and compared with each estimated current value obtained from each coordinate data, and if there is a difference exceeding the allowable value, multiple This is to have a multiple push detection means for determining a push. The configuration of the related invention is characterized in that the coordinate data obtained from between the electrodes a and b and between the electrodes cd is coordinate data of xy rectangular coordinates. Another configuration of the present invention is also characterized in that the touch panels A and B are made of a flexible transparent material having a transparent resistance film.

[0006]

When the operator presses the touch switch, coordinate data is obtained between the electrodes facing each other at the pressed point. If pressed multiple times, the coordinate data of the center of gravity is output. However, the current value increases between the adjacent electrodes because the contact area between the resistive films increases, so the estimated current value between the adjacent electrodes is estimated from the original coordinate data. Current value,
If it exceeds the error range, it is determined that the coordinate data is pressed multiple times. To detect the current value, specifically, use an electric current detection resistor that is sufficiently smaller than the resistance value of the panel switch plate in series with the circuit applied to the electrode, detect the voltage value, and obtain the estimated current value from the coordinate data. When the comparison is made using the data of the voltage value corresponding to the above, and it is determined that multiple pressing is performed, a multiple pressing signal is generated.

[0007]

Since multiple pressing of the analog touch switch can be detected, an erroneous position detection is prevented, a malfunction is prevented, and a highly reliable analog touch switch is provided.

[0008]

EXAMPLES The present invention will be described below based on specific examples. FIG. 1 shows a system 1000 of an analog touch switch having a set 100 of transparent touch panels formed of a transparent resistive film 10 having a uniform surface.
Are arranged so that the upper panel A and the lower panel B face each other so that their resistance films 10 do not come into contact with each other. Electrodes 12 and 1 are provided on the two sides of the upper panel A and the other two sides of the lower panel B, respectively.
3, 14, 15 are arranged and formed so that adjacent electrodes do not contact each other. The touch switch has a structure in which, when a point on the panel is pressed from the outside, only that part is deformed and the transparent resistance films 10 come into contact with each other.

In this system, the opposing electrodes 12-1
When a predetermined voltage is alternately applied between 3 and 14-15, the contact point has a potential distribution proportional to the distance between the electrodes and the distance between the electrodes is physically determined in advance as shown in FIG. The position (coordinates) of the contact point is determined by examining the voltage value. The voltage value can be measured by a voltage detecting means (voltmeter or the like) connected to the transparent electrode plate 10 in contact, and here, the voltage value is digitalized by the A / D converter provided in the data processing unit shown in FIG. It is configured so that it is processed and judged by a microcomputer. Since the electrodes are arranged so as to be orthogonal to each other as shown in FIG. 1, coordinate data of xy orthogonal coordinates can be obtained by applying a voltage to each of the two sets of electrodes. Note that pressing is performed with the fingertip, so the contact point is not the true point,
Since it has a certain spread area, voltage detection and current detection are set appropriately according to the panel used.

Consider a case where the touch panel is pressed twice. As shown in Fig. 3 (b), when double pressed and touched, the detected potential becomes the potential at the center of gravity between two points, and the coordinate data equivalent to Fig. 3 (a) is obtained. It will be. Therefore, it is impossible to guarantee reliable coordinate data of one point simply from the result of this potential measurement. This is also the case if the direction of the electrodes to be measured is changed and this double push must be detected by another means.

Therefore, considering the current flowing between the electrodes located adjacent to each other, as shown in FIG. 4, only the pressing point P is the point where the panel A and the panel B of FIG. 1 come into contact with each other. Therefore, the equal current lines used in FIG. 1 in which the currents flowing through the adjacent electrodes 13 and 15 are equal to each other are the broken line between the electrodes indicated by I ₀ in FIG. 4, which is determined by the resistance value of each panel. Therefore, if the coordinates of the depression point P as shown in FIG. 4 are obtained, the value of the current flowing between the adjacent electrodes can be obtained in advance. So in the case of double pressing, it is actually equivalent to connecting a resistor in parallel,
As for the current value, a current larger than that at a single point will flow. If the pressed point indicated by the obtained coordinate data is a true single pressed point, the current value on the isocurrent line shown in FIG. 4 should flow within the error range between the electrodes at the adjacent positions. The current flowing by applying a voltage between the adjacent electrodes is measured by the galvanic resistors R ₁ and R _{2 shown} in FIG. R ₁ and R ₂ are sufficiently smaller than the resistance value that constitutes the touch panel, and are values that keep the influence on the coordinate measurement within the error range.

FIG. 5 shows an example of a time chart for switching the voltage actually applied to the electrodes by the drive circuit of FIG. In this mode, the electrode 15 is grounded between the electrodes 14-15
As a result, the voltage V _H is applied. During this period, the X coordinate is detected as the electric potential. This potential is implemented by software in the microcomputer unit 300 which is the drive control unit and the data processing unit shown in FIG. The state of each data input shown in FIG. 1 at that time is shown in the time chart of FIG.
In the section, the potential X ₁ corresponding to the coordinates of the depression point P is input to the input terminal ADYS, and the potential X ₂ is input to the input terminal ADYD. Since no current flows, X ₁ = X ₂ . Therefore, in order to reduce the measurement error, the X-coordinate value corresponding to this potential is selected by taking the average of these two values.

Next, a voltage V _H is applied to the electrodes 13 and 15 which are adjacent to each other with the electrode 15 as the GND, and a voltage generated by flowing a current flowing between the electrodes to the galvanic resistance R _2. When the voltage drops, the voltage value at the input terminal ADT is detected. The voltage drop Z ₁ generated at this time is measured as shown in FIG.

In the next mode, the voltage V _H is applied between the electrodes 12 and 13 with the electrode 12 as the GND, and the potentials at this time are the potential Y _{1 at} the input terminal ADXS and the potential Y _{2 at the} input terminal ADYD (again Y ₁ = Y ₂ ) is detected. Therefore, the Y coordinate value is obtained from these values.

In the mode, the adjacent electrode 13 is again provided.
A voltage is applied between −15 and the voltage drop Z ₂ corresponding to the current flowing between the electrodes is measured at the same voltage value at the input terminal ADT. By performing the process of measuring twice, the error due to the measurement of the minute resistance is eliminated as much as possible.

The above measurement is carried out by the flow chart shown in FIG. Note that the flowchart in FIG. 7 is a basic configuration and is merely an example. Step 602
Is a part for checking whether or not a signal is generated by pressing the touch switch, and routinely constantly monitors the touch state. If there is an input, step 604
Then, first, the voltage of the mode in the section of FIG. 5 is applied to read the data of the X coordinate. Next, the mode for the section in step 606 is set, and the data for multiple press check is obtained. Then, in step 608, the voltage of the mode of the section is applied to measure the Y coordinate data. After that, in the mode of the section of step 610, the check data for multiple pressing is read again. Then, in step 612, from the results of each measurement, it is first checked whether there is a contradiction in the relationship between the coordinates X and Y, that is, whether it is within the measurement target range, etc. , Adjacent electrodes (electrode 13 and electrode 1 in this embodiment) estimated from the obtained coordinate data.
5) Compare with the data of the voltage drop showing the current value flowing during 5), and check whether it is within the error range or not in step 61.
Determined by 4. If the obtained difference is equal to or larger than the allowable current value shown in FIG. 4, the coordinate data is invalidated, the data is canceled, and the signal is output to call the touch operator's attention.
As the processing, the touch monitoring routine is continued again.
If the comparison result of the current values is a valid value, it is determined that the double pressing is not performed, so the coordinate data obtained in step 616 is output, and the process returns to the touch monitoring.

The multi-push detection means in this embodiment is the same as the potential detection line of the ADT shown in FIG.
In the form of a program in the microcomputer 300 of step 606, step 610, step 612 shown in the flowchart,
And the steps 614 and 618, which are carried out by the time charts shown in FIGS.

In addition, in this embodiment, the double pressing check is performed on the electrodes 13 and 15, but the electrodes 12, 1
The same effect can be obtained by implementing the combination of four. In this case, however, the ADT terminals, keep the circuit configuration for inputting the potential of R ₁ not from R _2. In addition, if the circuit configuration is such that both potentials from R ₂ and R ₁ are input in parallel at the same time, and two types of measurements are made with the electrodes of both combinations, it is possible to achieve more reliable double-press data. . Further, if the circuit configuration is such that the voltage applied to the electrodes can be reversed, the method of reversing the relationship of voltage application shown in FIG. I do not care. In that case, the flow chart and the voltage application time chart are of course changed, but the method is basically the same as the method of the present invention.

As described above, with the configuration and the multiple push detection method of this embodiment, the coordinate data for the touch point of the touch switch can be detected by removing the multiple push and output, and a reliable analog touch can be obtained. A switch can be provided.

[Brief description of drawings]

FIG. 1 is a system diagram of an analog touch switch.

FIG. 2 is an explanatory diagram of the principle of a touch switch.

FIG. 3 is an equivalent circuit diagram when one point is pressed and when multiple points are pressed.

FIG. 4 is a principle diagram of multiple push detection.

FIG. 5 is a time chart diagram of applied voltages when the touch panel is pressed.

FIG. 6 is an explanatory diagram of signal input in the case of FIG.

7 is a flowchart of an example of realizing the operation of the system of FIG.

[Explanation of symbols]

10 Transparent Homogeneous Resistive Film 12, 13, 14, 15 Electrode 100 Touch Panel 200 Drive Circuit 300 Drive Control Section and Data Processing Section (Microcomputer) 1000 Analog Touch Switch System

Claims (3)

[Claims] 1. A pair of flexible touch panels A and B each having a rectangular homogeneous resistance film on the surface thereof and arranged so that the resistance films face each other in a non-contact manner, and electrodes a on two opposite sides of the A. b, and B is provided with electrodes c and d on two opposite sides at positions different from A, and a drive control unit for alternately applying a predetermined voltage between the electrodes ab and cd. And a touch detection unit that obtains coordinate data of the touched point by measuring the potential of the touched point where one of the touch panels A and B is touched and touched by a voltage measuring unit connected to the touch panel A or B. A second predetermined voltage is applied between the adjacent electrodes a-c or b-d to the analog touch switch including a data processing unit that processes the obtained coordinate data. Detects the current value between each pressing,
An analog-characterized image pickup device having a multi-push detection unit for comparing each estimated current value obtained from each coordinate data and determining a multi-push when there is a difference exceeding an allowable value.
Touch switch. 2. The analog touch switch according to claim 1, wherein the coordinate data obtained from between the electrodes a and b and between the electrodes cd is coordinate data of xy rectangular coordinates. 3. The analog touch switch according to claim 1, wherein the touch panels A and B are made of a flexible transparent material having a transparent resistance film.