JP2008059912A - Switching device with touch detection function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switching device with a touch detection function easy to be electrically connected with a printed wiring board of an electrode for touch detection of an operating member, excellent in operability, and with high reliability in electric connection. <P>SOLUTION: An operating button 3 is installed on a body 1 in free movement, a thin-film electrode 4 for touch detection is formed on the surface of the operating button 3, a connecting part 4a is formed with at least a part of it guided out to a face opposite to a face of the operating button 3 where fingers come to touch, a printed wiring board 6 with a wired part 10 in correspondence with the operating button 3 is arranged, a switch 9 operated by pressing operation of the operating button 3 is provided at the printed wiring board 6, and a contactor 11 is provided at the printed wiring board 6 for electrically connecting the electrode 4 for touch detection with the wired part 10 in contact with the connecting part 4a of the electrode 4 for touch detection. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a switch device with a touch detection function having a touch detection electrode for detecting when a finger touches an operation member.

For example, a switch device for selecting a display device that displays a plurality of selection units on a screen includes operation buttons as a plurality of operation members corresponding to the plurality of selection units, and an operation button selected by a user. A configuration is considered in which when a pressing operation is performed with a finger, a switch element disposed below the operation button operates to select and determine a corresponding selection unit in a display state.
In addition, a publicly known document corresponding to the problem to be solved by the present invention could not be found.

By the way, in the above-mentioned thing, the user needs to operate after seeing and selecting the operation button of the switch device. For this reason, the user needs to see both the operation button of the switch device and the screen of the display device, and there is a problem that the operability is not good.

  In order to deal with such a problem, the inventor considered the following. That is, when a finger touches the operation button of the switch device, this is detected, and the display state of the selection unit corresponding to the operation button is changed. According to such a configuration, since the position of the operation button in contact with the finger can be known by looking at the display screen, it is possible to operate by looking only at the display screen without looking at the operation button of the switch device. It becomes possible.

  As a switch device with a touch detection function for realizing this, the inventor considered, for example, a configuration (comparative example) shown in FIG. FIG. 3 is a longitudinal sectional view of the switch device with a touch detection function. An operation button 102 constituting an operation member is movably accommodated in the body 101. The operation button 102 is formed in a rectangular container shape whose lower surface side is opened by plastic, and a thin-film touch detection electrode 103 is provided on the surface thereof. In addition, an insulating coating 104 is provided on the surface of the touch detection electrode 103.

  A printed wiring board 105 is disposed below the operation button 102, and printed wiring is provided on the printed wiring board 105. Further, a wiring portion 106 is provided on the component mounting surface (upper surface) of the printed wiring board 105, and one end portion of the connection line 107 is connected to the wiring portion 106 by soldering (or caulking). Is connected to the lower part of the side surface of the touch detection electrode 103 by soldering (or caulking).

  In the printed wiring board 105, a switch 108 as a switch element is disposed at a position corresponding to the lower end of the operation button 102. In the illustrated configuration, only one operation button 102 is provided, but actually, a plurality of units including the operation buttons 102 are provided corresponding to a plurality of selection units of the display device. Each switch 108 is connected to a control device (not shown) composed of, for example, a microcomputer.

  In the above configuration, when the user's finger comes into contact with the upper surface (insulating coating 104) of the operation button 102, the finger becomes the ground side and a capacitor is formed by the finger and the touch detection electrode 103. And the signal level of the touch detection circuit of the printed wiring board 105 changes. The control device detects the contact of the finger with the operation button 102 based on the change in the signal level, and puts the selection unit corresponding to the operation button 102 in the display state on the screen of the display device (not shown). When the operation button 102 is pressed downward, and the switch 108 is pressed by the lower end of the operation button 102, the switch 108 operates to output a selection signal and give it to the control device. The selection unit corresponding to 108 is set in a fixed display state, and selection of the selection unit is determined.

  However, in the switch device with a touch detection function configured as described above, the operation of connecting the connection line 107 to the thin-film touch detection electrode 103 by soldering (or caulking) is difficult and the workability is poor. Connection failure is likely to occur, and the reliability of electrical connection is also poor.

  The present invention has been made in view of the above circumstances, and its purpose is to facilitate electrical connection of the touch detection electrode of the operation member to the printed wiring board, excellent workability, and reliability of electrical connection. Another object is to provide a switch device with a high touch detection function.

  In order to achieve the above-described object, the switch device with a touch detection function of the present invention includes an operation member movably provided on the body, a switch element that operates based on a pressing operation of the operation member, A thin film is formed on the surface of the operation member to detect that the finger is in contact, and at least a part of the operation member is led out to a surface opposite to the surface on which the finger contacts. The formed touch detection electrode, a printed wiring board disposed corresponding to the operation member and having a wiring portion, and the touch detection electrode provided on the printed wiring board and in contact with the connection portion of the touch detection electrode And a contact for electrically connecting the detection electrode to the wiring portion.

  According to the present invention, since the contactor automatically electrically connects the touch detection electrode of the operation member and the wiring portion of the printed wiring board simply by incorporating the operation member and the printed wiring board into the body, the workability is improved. Excellent, no poor connection, and high electrical connection reliability.

An embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a longitudinal sectional view of a switch device with a touch detection function. In FIG. 1, a plastic body 1 has a rectangular container shape with an open bottom surface, which is formed with a button storage hole 2. The button storage hole 2 has an upper portion. Is made smaller than the other parts, and a step 2a is formed between them. An operation button 3 as an operation member is accommodated in the button storage hole 2 of the body 1 so as to be movable in a predetermined direction (vertical direction in FIG. 1). The operation button 3 is made of a light-transmitting plastic and is formed in a rectangular container shape having an open bottom surface. The operation button 3 is made smaller than other parts, and a step portion 3c is formed between the small portion 3a and the large portion 3b. Is formed.

  On the entire surface except the lower surface of the operation button 3, a thin film-like touch detection electrode 4 is formed by sputtering or plating with a conductive material. In this case, at least a part of the touch detection electrode 4 is led out to the lower surface of the large-sized portion 3b of the operation button 3 (the surface on the opposite side of the surface of the operation button 3 that is in contact with the finger). Is formed. Further, a translucent hole 4b is formed in the center of the upper surface of the touch detection electrode 4 (the surface on the side where the finger of the operation button 3 contacts). An insulating film 5 is provided on the surface of the touch detection requirement electrode 4 by coating with an insulating material, and this corresponds to the through hole 4b of the touch detection electrode 4 and transmits light for light projection. A hole 5a is formed. The insulating coating 5 is not provided on the connection portion 4a portion of the touch detection electrode 4.

  As shown in FIG. 1, a printed wiring board 6 is disposed below the operation button 3 so as to correspond to the lower surface of the operation button 3, and is fitted into the opening 1 a on the lower surface of the body 1. Yes. The printed wiring board 6 has a predetermined printed wiring. Further, an LED 7 for illumination of the operation button 3 is mounted near the center of the component mounting surface (upper surface) of the printed wiring board 6. Further, a flexible body 8 having a hollow conical shape made of an insulating material such as rubber (a state in which the cup is turned down) is fixed to the printed wiring board 6, and a pressure receiving portion 8 a on the upper side is provided on the lower surface of the operation button 3. It abuts on the pressing portion 3d from below and urges it upward. Thereby, the operation button 3 is urged upward, the step portion 3 c abuts on the step portion 2 a of the body 1, and the upper portion of the small portion 3 a is held in a state of slightly protruding from the upper surface of the body 1. A movable contact 9a is provided on the lower surface of the pressure receiving portion 8a of the flexible body 8, and fixed contacts 9b and 9b are provided on the component mounting surface of the printed wiring board 6 so as to face the movable contact 9a. 9 is configured.

  As shown in FIG. 1, a conductive material, for example, a copper wiring portion 10 is provided on a component mounting surface of the printed wiring board 6, and a contact 11 is provided. The contact 11 is made of a conductive material such as a leaf spring and is formed in a substantially inverted V shape. In this contactor 11, one end is fixed to the printed wiring board 6, the other end is slidably contacted with the wiring part 10 at the free end, and the intermediate part is connected to the connecting part 4 a at the lower end of the operation button 3 from below. It comes to be elastically pressed. Accordingly, the contact 11 is configured to electrically connect the touch detection electrode 4 to the wiring portion 10.

  In the configuration described above, only one operation button 3 is provided, but actually, a plurality of units including the operation buttons 3 are provided corresponding to a plurality of selection units of a display device (not shown). Each switch 9 is connected to a control device (not shown) composed of, for example, a microcomputer. A cover 12 that closes the cover 1 is fitted into the opening 1 a on the lower surface of the body 1.

  Next, the touch detection circuit 13 of the switch device with a touch detection function will be described with reference to FIG. The touch detection circuit 13 is a general capacitance detection circuit, and an oscillation unit 14 (one terminal is connected to the ground) that outputs a high-frequency signal, a load resistor 15, a high-frequency signal detection and smoothing. The detector 16 and the operational amplifier 17 are configured to perform the above.

  The touch detection electrode 4 is connected to the output terminal (the other terminal) of the oscillation unit 14 via the load resistor 15, the wiring unit 10, and the contact 11. The detection unit 16 includes a diode and a capacitor, and a high frequency signal from the oscillation unit 14 is input via the load resistor 15. The output of the detection unit 16 is input to the control device as a signal Vout amplified and offset via the operational amplifier 17. The oscillation unit 14, the load resistor 15, the detection unit 16, and the operational amplifier 17 are configured as a packaged capacitance detection IC 18.

Next, the operation of this embodiment will be described.
When the user's finger approaches the upper surface of the small portion 3 a of the operation button 3, the user's finger is connected to the ground. Therefore, a variable capacitor can be used between the user's finger and the touch detection electrode 4. C is formed. In such a state, when the user's finger touches the upper surface of the operation button 3, that is, the insulating coating 5, the capacitance of the capacitor C hardly changes. Thereby, the wiring part 10 of the printed wiring board 6 is connected to the ground via the contactor 11, the capacitor C, and fingers. Therefore, the high-frequency signal output from the oscillating unit 14 is divided by the resistance value of the load resistor 15 and the impedance of the capacitor C and input to the detection unit 16.

  As a result, since the level of the high-frequency signal input to the detection unit 16 is smaller than in a state where the finger is not touching the touch detection electrode 4, the signal Vout output via the detection unit 16 and the operational amplifier 17 is reduced. The level is also reduced. The control device detects the touch of the finger on the operation button 3 based on the change in the level of the signal Vout, and puts the selection unit corresponding to the operation button 3 in a temporary display state on the screen of the display device (not shown).

  Thereafter, when the operation button 3 is pressed downward by the user and the switch 9 is pressed by the pressing portion 3d of the operation button 3, the switch 9 operates (turns on) and the on signal is selected as a selection signal to the control device. The control device changes the selection unit corresponding to the operation button 3 to a fixed display state, and determines the selection of the selection unit.

  As described above, according to the present embodiment, the touch-sensitive electrode 4 is formed on the surface of the operation button 3 and the connecting portion 4a is formed on the lower surface, and the contact 11 is provided on the printed wiring board 6. The contact detection electrode 4 of the operation button 3 is electrically connected to the wiring portion 10 of the printed wiring board 6 by pressing the contact 11 to the connection portion 4 a. Accordingly, the touch detection electrode 4 of the operation button 3 is automatically electrically connected to the wiring portion 10 of the printed wiring board 6 by the contactor 11 simply by incorporating the operation button 3 and the printed wiring board 6 into the body 1. Therefore, the electrical connection is easy, the workability is excellent, the connection failure does not occur, and the reliability of the electrical connection is high.

The present invention is not limited to the embodiments described above and shown in the drawings, and the following modifications and expansions are possible.
In the above-described embodiment, a display device having a plurality of selection units is provided, and the selection of the selection unit is determined by the operation of the switch 9. For example, the display unit simply has a plurality of display units corresponding to a plurality of operation buttons. A display device may be provided.

Although the leaf spring contact 11 is provided in the above embodiment, a coil spring contact may be provided instead.
Moreover, in the said Example, although LED7 was provided, this should just be provided as needed.
Furthermore, in the said Example, although the insulating film 5 was provided in the operation button 3, this should just be provided as needed.

The longitudinal cross-sectional view of the switch apparatus with a touch detection function which shows one Example of this invention The figure which shows the equivalent circuit of the touch detection circuit FIG. 1 equivalent diagram showing a comparative example

Explanation of symbols

  In the drawing, 3 is an operation button (operation member), 4 is a touch detection electrode, 5 is an insulating coating, 6 is a printed wiring board, 9 is a switch (switch element), 10 is a wiring portion, 11 is a contact, and 13 is a contact. 2 shows a touch detection circuit.

Claims (1)

An operation member movably provided on the body;
A switch element that operates based on a pressing operation of the operating member;
A thin film is formed on the surface of the operation member to detect that the finger is in contact, and at least a part of the operation member is led out to a surface opposite to the surface on which the finger contacts. A formed touch detection electrode;
A printed wiring board disposed corresponding to the operation member and having a wiring portion;
Provided with this printed wiring board, comprising a contact for contacting the touch detection electrode connecting portion and electrically connecting the touch detection electrode to the wiring portion. Switch device.

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