JPH0798631A - Stylus pen - Google Patents

Abstract

PURPOSE:To make the shift distance of a pen lead short and to improve operability by providing the airtight room of fluid, which is constituted so that a part of a wall can be moved, and the detection means of the capacitance change of a capacitance element and connecting the pen lead with the movable wall. CONSTITUTION:The capacitance element 8 is constituted so that a dielectric is sandwiched by two electrodes. When an interval between the two electrodes becomes small by added pressure, capacitance changes in proportion to added pressure. One end of the pen lead 2 is fixed to a piston 3 energized by a spring 4, and pure water 6 is airtightly held in a space 7 surrounded by a case 1 and the piston 3. Pressure added to the tip of the pen lead 2 is transmitted to the piston 3 and it pressurizes pure water 6. The capacitance of the capacitance element 8 arranged in pure water 6 changes by the pressure. The change is converted into an electric signal corresponding to added pressure by a detection circuit 13, and it is inputted to a coordinate input device. Since pure water 6 is not compressible, the tip of the pen lead hardly moves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stylus pen used in a coordinate input device.

[0002]

2. Description of the Related Art Japanese Utility Model Publication No. 62-7515 discloses a stylus pen in which a pen core and a pressure-sensitive switch are connected and the pressure-sensitive switch is operated by moving the pen core.

[0003]

However, in order to operate the pressure sensitive switch, it is necessary to move the pen core by about 1.5 mm. Therefore, the operability was not good. ◆
An object of the present invention is to solve the above problems and to provide a stylus pen having a small pen core movement distance and good operability.

[0004]

Means for Solving the Problems The above-mentioned problems include an airtight chamber of a fluid in which a part of a wall is movable, an electrostatic capacitance element, and a detection means for detecting a capacitance change of the electrostatic capacitance element. This is solved by providing a capacitive element in an airtight chamber and connecting the pen core and the movable wall.

[0005]

When the fluid stored in the airtight chamber is a non-compressible liquid, the pressure applied to the pen core is transmitted to the airtight chamber, but the pen core hardly moves.

[0006]

1 is a sectional view of a stylus pen showing a first embodiment of the present invention. ◆ In the figure, 1 is a case.
Reference numeral 2 denotes a pen core, one end of which is fixed to the piston 3. Four
Is a spring that biases the piston 3. 5 is an O-ring. 6 is pure water, which is a liquid with a low electrical conductivity. The pure water 6 is hermetically held in a space 7 surrounded by the case 1 and the piston 3. 8 is a capacitance element. Here, as shown in FIG. 2, the capacitance element 8 has a structure in which a dielectric 9 is sandwiched by two electrodes 10 and has a function of a capacitor.
That is, when the distance between the two electrodes 10 is reduced by the pressing force F, the electrostatic capacitance changes substantially in proportion to the pressing force F. 1
Lead wires 1 and 12 connect the capacitance element 8 and the detection circuit 13. A cable 14 is connected to a coordinate input device (not shown). The operation will be described below. The pressure applied to the tip of the pen core 2 is transmitted to the piston 3 and pressurizes the pure water 6. This pressure changes the capacitance of the capacitance element 8 arranged in the pure water 6. And
The above change is converted into an electric signal according to the pressing force by the detection circuit 13 and connected to a coordinate input device (not shown). At this time, since the pure water 6 is incompressible, the tip of the pen core 2 hardly moves. The spring 4 may not be provided.

FIG. 2 is a sectional view of a stylus pen showing a second embodiment of the present invention. In the figure, 21 is an airtight container, and inside thereof is the piston 3, the spring 4, the O-ring 5, the pure water 6 and the capacitance element 8 in the first embodiment.
Is stored. The second embodiment is easier to assemble than the first embodiment. In addition, the operation is the above first
Since it is substantially the same as the embodiment described above, the description thereof will be omitted. ◆
In the above two embodiments, only the pressure applied to the tip of the pen core 2 is detected. However, a plurality of airtight containers are provided and another operation button is provided on the side surface of the case 1 to transmit additional information. It can also be configured to. It can also be applied to a so-called cordless stylus pen that does not have a cable connected to the coordinate input device.

[0008]

As described above, according to the present invention, the moving distance of the pen core is small and the operability is improved. Further, the capacitance element 8 may be arranged anywhere inside the airtight container, that is, the degree of freedom of arrangement is great, and the assembly is easy.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a diagram for explaining a capacitance element.

[Explanation of symbols]

 1 Case 2 Pen core 3 Piston 6 Pure water 8 Capacitive element 21 Airtight container

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Seiichi Nakano 2100 Kamiimazumi, Ebina City, Kanagawa Prefecture, Hitachi Seiko Co., Ltd. (72) Inventor, Kinji Sugimoto 2100, Kamiimazumi, Ebina City, Kanagawa Prefecture

Claims (1)

[Claims] 1. An airtight chamber for a fluid, comprising: a fluid-tight chamber in which a part of a wall is movable; an electrostatic capacitance element; and detection means for detecting a capacitance change of the electrostatic capacitance element. And a pen core and the movable wall are connected to each other.