JP2007122891A - Touch key and electric apparatus using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a touch key capable of miniaturizing an operating part. <P>SOLUTION: In a panel part 1 equipped with surface electrode parts 2, 3 and a back electrode part 4, a portion where one of the surface electrode parts 2, 3 is provided and another portion where the other of the surface electrode parts 2, 3 is provided are formed by electrical insulating materials 1a, 1b each having different dielectric constants. Thereby, since capacitance which the adjoining surface electrode parts 2, 3 and the back electrode part 4 form respectively can be changed, when identifying which one of the surface electrode parts 2, 3 a person has touched, identifying sensitivity can be increased by widening a difference in the capacitance and the operating part can be miniaturized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a touch key that increases identification sensitivity during a touch operation and can be downsized, and an electric device using the touch key.

  Conventionally, as this type of touch key, an electrode portion is provided on both front and back surfaces of a panel portion made of an electrical insulator such as glass, and a capacitor is formed by the electrode portion and the panel portion on both the front and back surfaces ( For example, see Patent Document 1).

This is to apply the high frequency voltage generated from the oscillation part to the electrode part on the back of the panel part, and when the electrode part on the panel part surface is touched with a finger, the high frequency voltage is bypassed through each electrode part, the panel part, the finger, The detection unit detects that the voltage appearing on the electrode part on the back surface of the panel part is lowered, and knows the touch of the electrode part.
Japanese Utility Model Publication No. 57-106152

  However, in the conventional configuration, in order to identify which electrode unit a person has touched, a certain amount of space is required between the electrode units, and it is difficult to reduce the size of the operation unit.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a touch key that can increase identification sensitivity during a touch operation and can realize downsizing of an operation unit, and an electric device using the touch key. And

  In order to solve the above-described conventional problems, the touch key of the present invention and the electric device using the same are provided in the panel portion where one of the surface electrode portions and the other surface electrode portion are provided. Are made of electrical insulators having different dielectric constants.

  This makes it possible to change the capacitance formed by the adjacent front surface electrode portion and back surface electrode portion, thereby increasing the difference in capacitance when identifying which surface electrode portion a person touches. The identification sensitivity can be increased, and the operation unit can be downsized.

  The touch key of the present invention and the electric device using the touch key can increase the identification sensitivity at the time of a touch operation and can realize downsizing of the operation unit.

  According to a first aspect of the present invention, there is provided a panel portion formed of an electrical insulator, at least two surface electrode portions formed of a conductor provided adjacent to the surface of the panel portion, and the surface on the back surface of the panel portion. A back electrode portion formed of a conductor provided facing the electrode portion; an oscillating portion having an output end connected to the back electrode portion and outputting an output voltage of a predetermined frequency to the output end; and the back electrode portion A detection unit that recognizes that a person has touched the surface electrode unit due to a decrease in the detected voltage detected by the output voltage applied to the panel, and the panel unit is provided with one of the surface electrode units. Capacitance formed by the adjacent front surface electrode portion and back surface electrode portion by using a touch key composed of an electrical insulator having a different dielectric constant as a part where the other surface electrode portion is provided. Can change By increasing the difference between the capacitance in identifying whether a person touches any surface electrode parts, reduction in size of the operation portion can be enhanced identification sensitivity can be realized.

  According to a second invention, in particular, in the first invention, the back electrode portion is provided on the back surface of the panel portion so as to face the plurality of surface electrode portions, so that the number of the surface electrode portions touched with a finger is increased. Even if the number increases, the number of the back electrode portions is one, and it is not necessary to increase the number of oscillation portions and detection portions, so that the circuit configuration can be simplified, and the cost can be reduced and the reliability can be improved.

  According to a third aspect of the present invention, in particular, in the first or second aspect of the invention, the adjacent front surface electrode portions have different opposing areas formed between the back surface electrode portions, and thus the dielectric constant of the panel portion. In addition to the difference between the surface electrode part and the back electrode part, the difference in the opposing area formed between the two electrode parts provides a larger difference in the capacitance formed between the two electrode parts. Therefore, the operation unit can have a simple configuration, and can be inexpensive and highly reliable.

  In a fourth aspect of the invention, in particular, in any one of the first to third aspects of the invention, the adjacent front surface electrode portions have the same area as each other, and have different positional relationships with the opposite back surface electrode portions. Thus, since it is a configuration for identifying the operated surface electrode portion by providing a difference in the capacitance formed between the two electrode portions, the operation portion can be made simple, inexpensive and It can be highly reliable.

  In the fifth invention, in particular, in any one of the first to fourth inventions, when a person does not touch by providing a hole in which a conductor serving as a touch mark is removed at a predetermined position of the surface electrode portion. The area of the surface electrode portion can be reduced to reduce the operation sensitivity. When a person touches, the area of the surface electrode portion can be substantially increased to increase the operation sensitivity by touching the hole portion. For this reason, it is possible to prevent erroneous operation by increasing the difference in detection voltage between when the person touches and when the person does not touch.

  In the sixth aspect of the invention, in particular, in the fifth aspect of the invention, since the size of the hole is set smaller than the size that can be touched by a finger, all the holes are closed when the person touches the surface electrode portion. Thus, the operation sensitivity can be stabilized by setting the substantial size of the surface electrode portion to a predetermined electrode area, and erroneous operation can be prevented.

  In the seventh invention, in particular, in the fifth or sixth invention, the surface electrode portions adjacent to each other when the person touches the touch mark by changing the position of the hole to be the touch mark for each surface electrode portion. Can be made different from each other. Thereby, even if the surface electrode portion has the same area and the same capacitance, the capacitance when touched by a person is different, and the touched surface electrode portion can be identified.

  In the eighth aspect of the invention, in particular, an electric device such as an electromagnetic cooker that is safe and easy to use is provided by using the touch key in any one of the first to seventh aspects of the invention as an electric device formed on the panel operation unit of the device. Can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 and 2 show a touch key according to Embodiment 1 of the present invention.

  As shown in the figure, the touch key in the present embodiment includes a panel unit 1 formed of an electrical insulator such as glass or plastic, and at least a conductor formed adjacent to the surface of the panel unit 1. The output terminal is connected to the two surface electrode portions 2 and 3, the back surface electrode portion 4 formed of a conductor provided on the back surface of the panel portion 1 so as to face the surface electrode portions 2 and 3, and the back surface electrode portion 4. A person touches the surface electrode portions 2 and 3 because the voltage detected by detecting the output voltage applied to the back surface electrode portion 4 and the oscillation portion 6 that outputs an output voltage of a predetermined frequency to the output end has decreased. And a detection unit 7 that recognizes the above.

  And the panel part 1 comprised the part in which one of the surface electrode parts 2 and 3 was provided, and the part in which the other surface electrode parts 2 and 3 were provided with the electrical insulators 1a and 1b of a different dielectric constant. Is.

  Moreover, the area of the surface electrode part 2 and the surface electrode part 3 is the same, the surface electrode part 2, the back surface electrode part 4, and the electrical insulator 1a comprise a capacitor | condenser. Similarly, the surface electrode part 3, the back surface electrode part 4 The insulating material 1b also constitutes a capacitor. In addition, the back electrode portion 4 is provided on the back surface of the panel portion 1 so as to face the surface electrode portions 2 and 3.

  The operation and action of the touch key configured as described above will be described below.

  When the front surface electrode portions 2 and 3 are touched with the finger 5, the surface electrode portions 2 and 3 are grounded through a person, and the capacitance of the capacitor formed by the front surface electrode portions 2 and 3 and the back surface electrode portion 4 The output voltage of the oscillating unit 6 applied to the back electrode unit 4 changes according to the capacitance component. That is, when the capacitance is large, the amount of decrease in output voltage is larger than when the capacitance is small. The detecting unit 7 detects the high frequency voltage output from the oscillating unit 6 in the back electrode unit 4, thereby recognizing which of the front electrode units 2 and 3 has been touched from the difference in the detected voltage.

  As described above, the back electrode part 4 is common, and the surface electrode part 2 and the surface electrode part 3 have the same area, but the electrical insulator 1a existing between the front electrode part 2 and the back electrode part 4, Since the dielectric constants of the electrical insulator 1b existing between the front electrode part 3 and the back electrode part 4 are different, the capacitance Ca of the capacitor formed by the front electrode part 2 and the back electrode part 4, and the front electrode part 3 And the capacitance Cb of the capacitor formed by the back electrode portion 4 is different. Therefore, the detection voltage of the detection unit 7 when the surface electrode unit 2 is touched with the finger 5 and the detection voltage of the detection unit 7 when the surface electrode unit 3 is touched with the finger 5 are different. It is possible to recognize whether the surface electrode portion is touched by the finger 5.

  In the present embodiment, the back electrode part 4 is integrated so as to straddle the front electrode parts 2 and 3, but may be separated so as to face each other. In this case, although the circuit configuration is complicated, the identification sensitivity of the adjacent surface electrode portions 2 and 3 can be increased by utilizing the difference in capacitance caused by different dielectric constants existing between the electrode portions. Therefore, for example, even if the interval between the surface electrode portions 2 and 3 is narrowed, there is an effect that it is possible to make erroneous recognition difficult.

  As described above, in the touch key according to the present embodiment, the panel unit 1 includes an electrical insulator having a different dielectric constant between a portion where one of the surface electrode portions is provided and a portion where the other surface electrode portion is provided. Since the capacitances formed by the adjacent front surface electrode portions 2 and 3 and the back surface electrode portion 4 can be changed by configuring with 1a and 1b, it is possible to determine which front surface electrode portions 2 and 3 a person touches. It is possible to increase the identification sensitivity by increasing the difference in capacitance during identification. Therefore, even if the separation distance between the adjacent surface electrode portions 2 and 3 is reduced, it is possible to make it difficult to influence each other and to make it difficult to detect erroneous operations. Miniaturization can be realized by reducing the distance between two and three. In other words, if the surface electrode portions 2 and 3 are provided in the same region, the surface electrode portions 2 and 3 can be increased in size and a user-friendly touch key can be provided.

  Moreover, even if the number of front surface electrode parts touched with the finger 5 increases by providing the back surface electrode part 4 on the back surface of the panel part 1 so as to face the plurality of front surface electrode parts 2 and 3, the back surface electrode The number of the units 4 is one, and it is not necessary to increase the number of the oscillation units 6 and the detection units 7. The circuit configuration can be simplified, and the cost can be reduced and the reliability can be increased.

(Embodiment 2)
3 and 4 show a touch key according to Embodiment 2 of the present invention. The configuration is basically the same as that of the first embodiment, and the same elements are denoted by the same reference numerals and the description thereof is omitted.

  In the example shown in FIG. 3, the area of the surface electrode part 3 is made smaller than the area of the surface electrode part 2, and the areas facing the back electrode part 4 (partially indicated by broken lines) are mutually changed. Since the electrostatic capacity is determined by the area of the opposing electrode part, the surface electrode part 3 has a smaller area of the surface facing the back electrode part 4 than the front electrode part 2, and thus the electrostatic capacity becomes smaller. The difference in electrostatic capacitance due to the difference in the facing area enables the surface electrode portion 3 and the surface electrode portion 2 to be more accurately identified.

  In the case shown in FIG. 4, even if the surface electrode portions 2 and 3 have the same area, the area of the back electrode portion 4 (partially indicated by broken lines) facing the surface electrode portion 3 is By making the area smaller than the area of the portion facing the electrode portion 2, the capacitance of the capacitor formed by the front surface electrode portion 3 and the back surface electrode portion 4 is formed by the front surface electrode portion 2 and the back surface electrode portion 4. It becomes smaller than the capacitance of the capacitor. Therefore, even if the surface electrode portions 2 and 3 have the same area, it is possible to identify which electrode portion the finger 5 has touched.

  Also in the present embodiment, as in the first embodiment, the back electrode portion 4 is provided on the back surface of the panel portion 1 so as to face the plurality of front surface electrode portions 2 and 3, thereby providing a finger 5. Even if the number of front surface electrode portions to be touched increases, the number of the back surface electrode portions 4 is one and it is not necessary to increase the number of the oscillation portions 6 and the detection portions 7, simplifying the circuit configuration, low cost and reliability. Can be high.

(Embodiment 3)
5 and 6 show a touch key according to Embodiment 3 of the present invention. The configuration is basically the same as that of the first embodiment, and the same elements are denoted by the same reference numerals and the description thereof is omitted.

  In the case shown in FIG. 5, a hole 2a from which a conductor to be a touch mark is removed is provided at a predetermined position (in the center in the present embodiment) of the surface electrode portion 2, and a portion of the hole 2a when a person operates. (For example, the user prints and displays in a specific color so that the user can naturally touch the part). In the surface electrode part 2, when a person does not touch, the area of the surface electrode part 2 is reduced by the area of the hole 2a to reduce the operation sensitivity. When the person touches, the top of the hole 2a is touched, and the hole 2a By touching this portion, the substantial area of the surface electrode portion 2 is increased to increase the operation sensitivity. As a result, the difference in detection voltage between when the person touches and when the person does not touch is increased to prevent erroneous operation. Although the surface electrode portion 3 is omitted without being shown, it may have either a configuration provided with holes similar to the surface electrode portion 2 or a configuration without holes.

  Further, in the case shown in FIG. 6, the surface electrode 2 is provided with a hole 2b and the surface electrode 3 is provided with a hole 3b. (In this embodiment, the positions of the holes 2b and 3b are shifted in different directions with respect to the centers of the surface electrode portions 2 and 3). Thereby, when a person touches a touch mark, the electrostatic capacity formed with the back surface electrode part 4 which the adjacent surface electrode parts 2 and 3 each oppose can mutually differ. Therefore, even when the surface electrode portions 2 and 3 have the same area and the same capacitance, the capacitance when touched by a person is different and the touched surface electrode portions 2 and 3 can be identified. . When the person does not touch, the surface electrode portions 2 and 3 have holes 2b and 3b, so the surface electrode portions 2 and 3 cannot obtain a predetermined area. It is safe for small animals to touch.

  Also, if the size of the holes 2a, 2b, and 3b shown in FIGS. 5 and 6 is set smaller than the size that can be touched by a finger, when the person touches the surface electrode portions 2 and 3, All the holes can be closed, and the operational sensitivity can be stabilized by setting the substantial size of the surface electrode portions 2 and 3 to a predetermined electrode area, and erroneous operation can be prevented.

(Embodiment 4)
FIG. 7 shows an electrical apparatus according to Embodiment 2 of the present invention.

  As an electric device in the present embodiment, an electromagnetic cooker 13 is shown as an example, and this is provided with a panel portion 9 constituting a ceramic top plate on the upper portion of the body, and on the upper surface of the panel portion 9. Touch keys 10, 11, and 12 adopting the configuration shown in any of the first to third embodiments are provided together with the heating coil display portions 8 and 14 indicating the position of the heating coil (not shown). The touch key 10 is a set temperature decrease key, the touch key 11 is a power on / off key, and the touch key 12 is a set temperature increase key.

  By adopting the above-described configuration, a person can operate the touch keys 10, 11, and 12 from the upper surface, and the operation becomes extremely simple. Moreover, since the heating coil display parts 8 and 14 occupy a wide range and the touch keys cannot be close to them, the arrangement space of the touch keys is limited, but the touch keys shown in the first to third embodiments are limited. Since it can be downsized and can prevent malfunction, it can be an easy-to-use electromagnetic cooker without malfunction.

  As described above, the touch key and the electric device using the touch key according to the present invention can increase the identification sensitivity at the time of the touch operation and can reduce the size of the operation unit. In particular, the present invention can be applied not only to homes such as appliances having a flat panel such as an electromagnetic cooker but also to various industrial fields.

Cross-sectional side view of the main part of the touch key according to Embodiment 1 of the present invention. Plan view of electrode part of the touch key The top view of the electrode part of the touch key in Embodiment 2 of this invention (A) Top view which shows the other structure of the electrode part in the same touch key (b) Same side sectional drawing The top view of the electrode part of the touch key in Embodiment 3 of this invention The top view which shows the other structure of the electrode part in the same touch key Plan view of electric equipment using touch key according to Embodiment 4 of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Panel part 1a, 1b Electrical insulator 2, 3 Front surface electrode part 2a, 2b, 3b Hole 4 Back surface electrode part 6 Oscillation part 7 Detection part

Claims (8)

A panel portion formed of an electrical insulator, at least two surface electrode portions formed of a conductor provided adjacent to the surface of the panel portion, and a back surface of the panel portion facing the surface electrode portion A back electrode portion formed of a provided conductor; an oscillating portion having an output terminal connected to the back electrode portion and outputting an output voltage of a predetermined frequency to the output end; and an output voltage applied to the back electrode portion And a detection unit that recognizes that a person has touched the surface electrode unit due to a decrease in the detected voltage, and the panel unit includes a portion provided with one of the surface electrode units, A touch key composed of an electrical insulator having a different dielectric constant from the portion provided with the surface electrode portion. The touch key according to claim 1, wherein the back electrode portion is provided on the back surface of the panel portion so as to face the plurality of front surface electrode portions. The touch key according to claim 1 or 2, wherein adjacent surface electrode portions have different sizes of opposing areas formed between the back surface electrode portion and each other. The touch key according to any one of claims 1 to 3, wherein adjacent front surface electrode portions have the same area and have different positional relationships with the opposite back surface electrode portions. The touch key according to any one of claims 1 to 4, wherein a hole from which a conductor to be a touch mark is removed is provided at a predetermined position of the surface electrode portion. The touch key according to claim 5, wherein the size of the hole is set to be smaller than a size that a person can touch with a finger. The touch key according to claim 5 or 6, wherein a position of a hole to be a touch mark is different for each surface electrode portion. An electrical device in which the touch key according to any one of claims 1 to 7 is formed on a panel operation unit of the device.

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