JPS6055427A - Coordinate input device - Google Patents

Abstract

PURPOSE:To improve the sliding of an input pen add to improve the durability by mixing a lubricant into one of two detection plates, i.e. the 1st detection plate which is rubbed with the input pen. CONSTITUTION:The coordinate input device consists of the 1st detection plate 1 formed by sticking a resistance film 12 to the reverse surface of an insulating plate 13 with plasticity and providing electrodes 3 and 4 to two facing sides and the 2nd detection plate 8 which is similar to said detection plate and provided thereunder across a spacer 7. Both detection plates of this device conduct to each other electrically when specific pressure is applied with the pen 2, so arithmetic is performed by an arithmetic device through a position detecting circuit 9 to detect the position coordinates of the pen 2. In this case, a lubricant having good external lubricity, e.g. higher fatty acid or its metallic salt, wax, etc., are mixed into the insulating plate 13.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a coordinate input device for handwritten characters.

The configuration of the conventional example and its problems A coordinate input device detects 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 CUT.

In order to know the position of a pen for handwriting input, conventionally known coordinate input devices are equipped with detection plates that detect coordinate positions in the X-axis direction and Y-axis direction. There is a method in which the pen receives the position signal from the detection plate through inductive or capacitive coupling between the plate and the pen, and conversely, the position coordinates of the pen are determined by receiving the signal from the pen on the detection plate. .

Another conventionally known coordinate input device uses a resistor plate with uniformly distributed resistance values.

A conventional method using this resistor plate will be explained below with reference to the drawings.

In Figure 1, 1 is the first detection plate, which has a resistive film with a uniformly distributed resistance value attached to the bottom surface of a flexible insulating plate so that the point input with the pen 2 is deformed downward. , and further has electrodes 3° and 4 on its two opposing sides. A resistive film with a uniformly distributed resistance value is attached to the upper surface of the insulating plate below the first sensing plate 1, and electrodes 6, 6 are placed on two opposing sides at different positions from the first sensing plate 1. A second detection plate 8 is opposed to the first detection plate 1 and has insulators 7 attached at predetermined intervals on the resistive film as spacers for insulation by providing gaps between the second detection plate 8 and the first detection plate 1 . When there is no input by the pen 2, the first detection plate 1 and the second detection plate 8 are not electrically connected due to the insulator 7,
If a pressure above a predetermined value is inputted to any point on the detection plate 1, the first detection plate 1 has removability and is electrically connected to the second detection plate 8 at the input point. At this time, for example, if a constant voltage is applied between electrodes 3 and 4, a divided voltage opposite to the position of the pen 2 in the X-axis direction will be derived at electrode 6, and conversely, if a constant voltage is applied between electrodes 6 and 6, a divided voltage will be derived at electrode 6. 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 3, so that the coordinates of the input position of the pen 2 can be known. The position detection circuit 9 applies a constant voltage between these series of electrodes, derives a divided voltage from the other electrodes, and alternately switches between these two operations in the X-axis direction and Y-axis direction.
This is done by The position detection circuit 9 also performs analog-to-digital conversion on the input divided voltage and outputs it to the arithmetic unit as position information. The arithmetic device can determine the coordinates of the input position of the pen 2 by performing simple calculations, and can also display characters input with the pen 2 on a display device such as a CRT.

FIG. 2 is a front sectional view of the conventional coordinate input device shown in FIG. As mentioned above, the first. The second detection plates 1 and 8 are composed of insulating plates 1o and 130 with resistive films 11 and 12 having uniformly distributed resistance attached to one side,
An insulator 7 is placed on the second detection plate 8.

In the above device, characters, figures, etc. are input by moving the pen 2 in an arbitrary direction. When placing the pen 2 on the surface of the insulating plate 130 of the first detection plate, the tip of the pen 2 may scratch the surface of the insulating plate 130, causing cracks in the resistive film 12 attached to the insulating plate 13. Therefore, the uniformity of the resistive film 121C of the tenth sensing plate 1 is lost, resulting in an error in reading coordinates different from the input.

OBJECT OF THE INVENTION The present invention aims to solve such conventional problems and provide a durable coordinate input device. The insulating plate of the first detecting plate that comes into contact with the pen is coated with a lubricant with high external lubricity. It is mixed with. The lubricants with high external lubricity are higher fatty acids and fatty acid amide compounds.

These include metal salts of higher fatty acids and waxes.

DESCRIPTION OF THE EMBODIMENTS The basic configuration of the coordinate input device of the present invention is the same as that shown in FIGS. There is a difference between The types of lubricants, durability test methods, and durability test results will be described in detail below.

(2) Types of lubricants Table 1 shows the lubricants studied. Note that a polyester film was used as the insulating plate 13 of the first detection plate 1.

(Left below) ■Durability test method In a coordinate input device like the one shown in Figure 2, I B
A straight line of 10 m was input with a force of og.

This line was monitored with a CRT, and the life was determined when distortion occurred. The insulating plate 10 was a glass plate, and the removable insulating plate 13 was a lubricant type polyester film. The resistive films 11 and 12 were ITO films. The insulator 7 was made of silicone rubber.

(2) Durability test results When the lifespan of the polyester film as shown in Figure 2 was examined without adding any lubricant, it withstood about 3000 degrees of writing input. However, there are variations in the kana depending on the method of handwritten input, and there are variations over +600 times 1-1000 times. On the other hand, if a lubricant-type polyester film is used for the insulating plate 13, the
It was about 600 times, and the variation in life was about ±300 times.

Among the lubricants studied, &2.應71A3+應4 etc. are particularly preferred as they move smoothly. Furthermore, for A1-A4, results were obtained that were more preferable when the amount added was larger.

Table 2 shows the durability test results.

Table 2 All of these lubricants have high external lubricity and reduce the boundary friction between the insulating plate 13 and the pen 2. Such slipperiness is thought to be due to the lubricant added to the insulating plate 13 having poor compatibility with the insulating plate paste and bleeding onto the insulating plate surface. therefore,
It is believed that lubricants other than those listed in Table 2 will be sufficiently effective as long as they have a polar group that maintains appropriate compatibility with the insulating plate paste and a nonpolar group that has a lubricating effect. In addition, the type and effect of the lubricant will differ depending on the insulating board base.In order to maintain the transparency of the insulating board base, we considered using a low additive amount as shown in Table 2, but transparency is not necessary. In such cases, it is preferable to increase the amount added.

Effects of the Invention As described above, in the coordinate input device of the present invention, a lubricant having high external lubricity is mixed into the flexible first detection plate which is rubbed by an input pen among the two detection plates. By improving the lubricity of the input pen without using a separate film, the pen tip has less scratchiness and is more durable than conventional coordinate input devices using this method. Good things are obtained, and the effects are extremely high.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing the coordinate input device, and FIG. 2 is a front sectional view thereof. 1...First detection plate, 2...Pen, 7
...Insulator (spacer), 8...2nd
Detection plate, 10°13... Insulation plate, 11...
. . . Resistive film of the second detection plate, 12 . . . Resistive film of the first detection plate.

Claims (1)

[Claims] a first sensing plate having a resistive film attached to the lower surface of a flexible insulating plate and having electrodes on two opposing sides; a second sensing plate having a resistive film attached thereto and having electrodes on two opposing sides; and an insulator providing a gap between the first sensing plate and the second sensing plate; A coordinate input device whose insulating plate has a lubricant that has excellent external slipperiness.