JP2019074425A - Detector and input device - Google Patents

Abstract

To provide a detector and an input device that can have a simplified wiring structure.SOLUTION: The present invention includes: a substrate 5; a first detection electrode 10 formed on a bottom surface 5a of the substrate 5; a ground electrode 30 on the same surface of the surface where the first detection electrode 10 is formed, the ground electrode surrounding the first detection electrode 10 and being grounded; an elastic body 40 on the bottom surface 5a of the substrate 5; and a conductor 50 formed on the lower surface 40b of an elastic body 40, which is opposite to the substrate 5, the ground electrode 30 and the conductor 50 being capacitive-coupled and a virtual ground state being generated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a detection device and an input device.

  Conventionally, there is a detection device that detects a pressure (load) by detecting a change in volume (see, for example, Patent Document 1).

  The detection device includes a detection unit provided on one surface side of the insulating substrate, a circuit element provided on the other surface side of the substrate for processing a signal detected by the detection unit, and a substrate penetrating in the thickness direction. A detection unit configured to be a pressure (load) sensor on the detection electrode layer of the substrate, and the pressure sensor detects the chip mounting surface on the back surface of the substrate It comprises the circuit element which processes the electric signal which was carried out. A metal plate (counter electrode) is attached by adhesion on the detection electrode layer, and is connected to a terminal through a through hole electrode penetrating from the detection electrode layer to the chip mounting surface. In addition, a thin plate is used for this metal plate, and it is elastically deformed in the direction approaching / separating to the detection electrode by fluid pressure, and the capacitance of the signal detection capacitor consisting of the metal plate and the detection electrode increases or decreases. The pressure (load) is detected by

Unexamined-Japanese-Patent No. 2003-329443

  In the prior art, it is necessary to connect the ground electrode to the takeout terminal with a through hole electrode, resulting in a problem that the wiring becomes complicated.

  Therefore, an object of the present invention is to provide a detection device and an input device capable of simplifying the wiring configuration.

[1] In order to achieve the above object, the substrate, the first detection electrode formed on the bottom side of the substrate, and the same surface as the first detection electrode surround at least the periphery of the first detection electrode. And an elastic body provided on the bottom surface side of the substrate, and a conductor formed on the surface of the elastic body opposite to the substrate, the ground electrode and the ground electrode Capacitive coupling with a conductor provides a sensing device in which a virtual ground condition is generated.
[2] A second detection electrode is formed on the same surface as the first detection electrode without being in contact with the first detection electrode, and the ground electrode includes the first detection electrode, and the second detection electrode. The detection device according to the above [1] may be formed so as to surround the periphery of the detection electrode.
[3] Moreover, a detection unit that detects an electrostatic capacitance between the first detection electrode and the second detection electrode is provided, and the detection unit is configured to connect the bottom surface side sandwiching the elastic body and the conductor. The detection device according to the above [1] or [2] may be a load that is detected based on a change in capacitance due to a change in distance therebetween.
[4] The detection device according to the above [2] or [3], wherein the first detection electrode and the second detection electrode are each formed in a comb shape and disposed so as to mesh with each other. It may be
[5] A detection unit for detecting an electrostatic capacitance based on the self-capacitance of the first detection electrode is provided, and the detection unit is based on a change in distance between the bottom side sandwiching the elastic body and the conductor. It may be the detection device according to the above [1], which detects a load based on a change in capacitance.
[6] Further, the input device may be a detection device according to any one of the above [1] to [5] and a touch panel that detects an electrostatic capacitance to perform touch detection.

  According to the detection device or the input device of the present invention, it is possible to provide the detection device and the input device capable of simplifying the wiring configuration.

FIG. 1 is an entire configuration diagram of a detection device and an input device according to an embodiment of the present invention. FIG. 2 is a partial cross-sectional view of a load sensor portion in a state where the detection device and the input device shown in FIG. 1 are assembled. FIG. 3 is an A arrow view showing an example of an electrode pattern when each electrode on the substrate is viewed from the A direction in FIG. FIG. 4 is a schematic block diagram of a detection device and an input device according to an embodiment of the present invention.

First Embodiment of the Present Invention
The load sensor 1 as a detection device according to the first embodiment of the present invention includes the substrate 5, the first detection electrode 10 formed on the bottom surface 5 a side of the substrate 5, and the same surface as the first detection electrode 10. A ground electrode 30 formed to surround at least the periphery of the first detection electrode 10, an elastic body 40 provided on the bottom surface 5a side of the substrate 5, and an elastic body 40 on the opposite side of the substrate 5 And a conductor 50 formed on the lower surface 40b, and is configured such that a virtual ground state is generated by capacitive coupling between the ground electrode 30 and the conductor 50.

  In the first embodiment, the second detection electrode 20 formed on the same surface as the first detection electrode 10 without contacting the first detection electrode 10 is provided, and the ground electrode 30 is a first detection electrode. A description will be given as a mutual capacitance type electrode configuration which is formed to surround the periphery of the second detection electrode 20 and the second detection electrode 20.

  The detection unit 60 further includes a detection unit 60 that detects an electrostatic capacitance between the first detection electrode 10 and the second detection electrode 20. The detection unit 60 is disposed between the conductor 5 and the bottom surface 5a side sandwiching the elastic body 40. The load is detected based on a change in capacitance due to a change in distance.

  The embodiment of the present invention will be described as an input device 7 provided with the above-described load sensor 1 and a touch panel 70 for detecting a capacitance and performing touch detection.

  For example, as shown in FIG. 1, the input device 7 detects a load sensor 1 for detecting a pressing operation on the operation surface 100a and a touch operation on the operation surface 100a, a tracing operation, a tap operation, a pinch operation and the like. The touch panel 70 is roughly configured. This input device 7 is, for example, disposed on the floor console between the driver's seat and the front passenger's seat of the vehicle.

(Configuration of load sensor 1)
As shown in FIG. 1, one or more load sensors 1 are disposed in accordance with the shape of the operation surface 100 a. The arrangement according to the shape of the operation surface 100a is, for example, a well-balanced arrangement according to the shape of the operation surface 100a, and more specifically, the center of gravity determined by the plurality of load sensors 1 is of the operation surface 100a. It is arranged to coincide with the center of gravity. As an example, as shown in FIGS. 1 and 2, the plurality of load sensors 1 of the present embodiment are located below the four corner sides of the operation surface 100a having a rectangular shape as a well-balanced arrangement adapted to the shape of the operation surface 100a. In other words, they are disposed on the back and back sides of the operation surface 100a. That is, the input device 7 includes four load sensors 1. The outer shape of the operation surface 100a is not limited to a rectangular shape, and may be a circular shape, a triangular shape, a trapezoidal shape, or a combination of these. In addition, the operation surface 100a may have a flat surface, a concave surface, a convex surface, or a shape combining these.

  As shown in FIG. 1, the substrate 5 has, for example, a shape corresponding to the operation surface 100a of the panel 100, and wirings such as the load sensor 1, the touch panel 70, and other circuit parts, electronic components, etc. are formed and mounted. There is. The substrate 5 is, for example, a glass epoxy substrate, and in the present embodiment, as shown in FIG. 2, the substrate 5 includes the first detection electrode 10, the second detection electrode 20, and the ground electrode 30 of the load sensor 1. Wiring part 31 grade | etc., Is formed and sensor IC which is the control part 6 is mounted, and a part of board | substrate 5 functions as a component of the load sensor 1. FIG.

  As shown in FIG. 2, the bottom surface 5a of the substrate 5 is a circuit pattern surface and a component mounting surface, and the first detection electrode 10, the second detection electrode 20, and the same surface which is the bottom surface 5a. A ground electrode 30 is formed. The first detection electrode 10, the second detection electrode 20, and the ground electrode 30 are pattern-formed on the substrate 5 by copper foil or the like in a predetermined shape.

  As shown in FIG. 3, the first detection electrode 10 and the second detection electrode 20 are formed in, for example, a comb shape, and are arranged to be engaged with each other. The first detection electrode 10 and the second detection electrode 20 are formed in a non-contact state. As a result, the first detection electrode 10 and the second detection electrode 20 are in a state of being capacitively coupled with a predetermined capacitance. As shown in FIG. 2, the first detection electrode 10 and the second detection electrode 20 are connected to the control unit 6 by the wiring unit 31 on the substrate 5.

  Further, as shown in FIG. 3, the ground electrode 30 is formed to surround the first detection electrode 10 and the second detection electrode 20. The ground electrode 30 is connected to the control unit 6 by the wiring unit 31 on the substrate 5 as shown in FIG. The ground electrode 30 is grounded to the ground (or common) in the control unit 6.

  As shown in FIG. 2, the elastic body 40 is provided on the bottom surface 5 a side of the substrate 5. The elastic body 40 is formed of, for example, silicon or the like with a predetermined elastic modulus (Young's modulus) and a predetermined thickness t. The elastic body 40 is formed, for example, in substantially the same size as the area of the first detection electrode 10, the second detection electrode 20, and the ground electrode 30.

  The elastic body 40 is disposed such that the top surface 40 a is in contact with the bottom surface 5 a of the substrate 5 as shown in FIG. 2. In the present embodiment, the upper surface 40 a of the elastic body 40 is fixed to the bottom surface 5 a of the substrate 5 by adhesion or the like.

  A conductor 50 is formed on the lower surface 40 b of the elastic body 40 opposite to the substrate 5. The conductor 50 can be formed, for example, by conducting printing of conductive carbon. In addition, for example, a copper foil, a conductor plate, a conductor seal or the like may be fixed to the lower surface 40 b of the elastic body 40 by adhesion, adhesion or the like.

  The conductor 50 is formed, for example, on the entire surface of the lower surface 40 b of the elastic body 40. Therefore, capacitive coupling is provided between the first detection electrode 10 and the conductor 50. Similarly, the second detection electrode 20 and the conductor 50 are also capacitively coupled.

  The ground electrode 30 and the conductor 50 are also capacitively coupled. As described above, the ground electrode 30 is connected to the control unit 6 by the wiring unit 31 and is grounded to the ground (or common). Therefore, the conductor 50 is pseudo connected to the ground by capacitive coupling.

  As shown in FIG. 2, the lower surface 40 b of the elastic body 40 and the conductor 50 are disposed in contact with the base 80. Also, the base 80 is disposed on the housing 90 via the cushion 85. Therefore, as shown in FIGS. 1 and 2, when the operation on the operation surface 100 a of the panel 100 is pressed, the operation unit 75 is moved downward by the elasticity of the cushion 85.

  Further, since the elastic body 40 is sandwiched between the substrate 5 and the base 80, the thickness t of the elastic body 40 is changed by the pressing operation on the operation surface 100a of the panel 100. Specifically, the thickness t is reduced by the elastic body 40 being compressed. That is, the distance between the bottom surface 5a side sandwiching the elastic body 40 and the conductor 50 changes, and the capacitance of the capacitor formed of the first detection electrode 10, the second detection electrode 20 and the conductor 50, and the ground electrode 30 The capacitance of the capacitor formed by the conductor 50 will change. The detection unit 60 can detect a change in electrostatic capacitance due to a pressing operation on the operation surface 100a, and calculate the applied load.

  The detection unit 60 detects the capacitance between the first detection electrode and the second detection electrode. In addition, the detection unit 60 can detect the load based on the change in capacitance due to the change in distance between the conductor 50 and the bottom surface 5 a side sandwiching the elastic body 40.

  The detection unit 60 is configured using the microcomputer function of the control unit 6. The control unit 6 includes, for example, a central processing unit (CPU) that performs computation, processing, and the like on acquired data according to a stored program, a random access memory (RAM) that is a semiconductor memory, and a read only memory (ROM). Is a microcomputer that In the ROM, for example, a program for operating the control unit 6 and a load value corresponding to the detected capacitance value are stored in a table format. In addition, a touch threshold and the like used for touch detection by the touch panel 70 described later are stored. The RAM is used, for example, as a storage area for temporarily storing operation results and the like.

(Operation of load sensor 1)
When the operation surface 100a of the panel 100 is pressed downward, the thickness t of the elastic body 40 changes. This converts the load into a distance.

  When the thickness t of the elastic body 40 changes, the capacitance value of the capacitor formed by the first detection electrode 10 and the conductor 50, the capacitance value of the capacitor formed by the second detection electrode 20 and the conductor 50, the ground electrode 30 and the conductor 50 The capacitance value of the capacitor formed by

  The detection unit 60 detects this change in capacitance value. Specifically, for example, the detection unit 60 applies a voltage to the first detection electrode 10 for a predetermined time with a pulse signal of a predetermined voltage and a predetermined frequency to perform charge charging. The detection unit 60 detects the charge amount charged from the second detection electrode 20. The detection unit 60 quantizes the detected charge amount with a counter to detect a capacitance value as a digital amount.

  The detection unit 60 or the control unit 6 calculates the load value by referring to the table (load value corresponding to the capacitance value) stored in the ROM based on the detected capacitance. Thereby, it is possible to detect the load (operation load) when the operation surface 100a is pressed downward.

Second Embodiment of the Present Invention
The second embodiment of the present invention has a self-capacitance electrode configuration without the second detection electrode 20. The detection device according to the second embodiment includes a detection unit that detects an electrostatic capacitance based on the self-capacitance of the first detection electrode, and the detection unit is a distance between the bottom side sandwiching the elastic body and the conductor. The load is detected based on the change in capacitance due to the change.

  The difference from the first embodiment is that the detection unit 60 detects the self-capacitance of the first detection electrode. That is, the electrostatic capacitance between the operation surface 100a and a finger or the like touched on the operation surface 100a is detected. The electrostatic capacitance detection operation of the detection unit 60 applies a charge to the first detection electrode 10 by applying a predetermined voltage and a pulse signal of a predetermined frequency for a predetermined time. The detection unit 60 detects the amount of charge charged from the first detection electrode 10. The detection unit 60 quantizes the detected charge amount with a counter to detect a capacitance value as a digital amount. The other configuration and operation are similar to those of the first embodiment.

(Input device 7)
As shown in FIG. 4, the control unit 6 (detection unit 60) is provided with a load sensor 1 and a touch panel 70, and detects a load and various touches by detecting the capacitance value of the load sensor 1 or the touch panel 70. The input device 7 can be configured. The control unit 6 (detection unit 60) has a detection method of detecting the capacitance value, and is common to the load sensor 1 and the touch panel 70. Therefore, the control unit 6 (detection unit 60) can be commonly used to detect the capacitance value of the load sensor 1 and the touch panel 70, or a microcomputer having the same specification can be used.

(Touch panel 70)
The touch panel 70 is, for example, a capacitive touch sensor, and is configured to detect multi-touch. Specifically, in the touch panel 70, a plurality of drive electrodes and detection electrodes cross each other while maintaining insulation, and are provided on the substrate. The capacitances of all combinations of the plurality of drive electrodes and the plurality of detection electrodes are read out and output to the control unit 6.

  The control unit 6 detects a touch position at which the capacitance value detected by the touch panel 70 exceeds the touch threshold as one or a plurality of touch operations. Based on these touch operations, touch operations, trace operations, tap operations, pinch operations and the like can be detected.

(Effect of the embodiment)
According to the embodiment of the present invention, the following effects are obtained.
(1) The load sensor 1 as a detection device according to the embodiment of the present invention has the substrate 5, the first detection electrode 10 formed on the bottom surface 5 a side of the substrate 5, and the same surface as the first detection electrode 10 The first detection electrode 10 and the second detection electrode 20 are surrounded on the same surface as the second detection electrode 20 formed in a non-contact state with the first detection electrode 10 and the first detection electrode 10. And an elastic body 40 provided on the side of the bottom surface 5a of the substrate 5, and a conductor 50 formed on the lower surface 40b of the elastic body 40 on the opposite side of the substrate 5 The capacitive coupling between the ground electrode 30 and the conductor 50 is configured to generate a virtual ground state. That is, the ground electrode 30 and the conductor 50 are virtually connected to the ground by capacitive coupling. As a result, it is not necessary to prepare special wiring from the conductor 50 side to the substrate 5, and the mechanical configuration of the load sensor 1 can be simplified.
(2) All the wiring related to the load sensor 1 can be performed on the substrate 5 and the jumper wiring from the conductor 50 to the substrate 5 side is not required. The load sensor 1 converts the load into a distance by pressing the operation surface 100 a of the panel 100 downward and changing the thickness t of the elastic body 40, and detects a change in capacitance due to the change in distance. Is the detection principle. Therefore, as shown in the prior art, when the ground connection is made from the conductor 50 to the substrate 5 side by the jumper wiring, the thickness t of the elastic body 40 is changed by the pressing operation of the operation surface 100a. And other problems are likely to occur. In the load sensor 1 according to the present embodiment, since there is no need to prepare a special wiring from the conductor 50 to the substrate 5 side, problems such as disconnection do not occur.
(3) Since both the load sensor 1 and the touch panel 70 have the commonality of detecting the capacitance value, the control unit 6 (detection unit 60) can be used in common, or a microcomputer of the same specification Has the advantage of being able to use

  Although some embodiments of the present invention have been described above, these embodiments are merely examples and do not limit the invention according to the claims. Moreover, these novel embodiments can be implemented in other various forms, and various omissions, replacements, changes, and the like can be made without departing from the scope of the present invention. Further, not all combinations of the features described in the embodiments are essential to the means for solving the problems of the invention. Furthermore, these embodiments are included in the scope and subject matter of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

DESCRIPTION OF SYMBOLS 1 ... load sensor, 5 ... board | substrate, 5 a ... bottom face, 6 ... control part, 7 ... input device, 10 ... 1st detection electrode, 20 ... 2nd detection electrode, 30 ... ground electrode, 31 ... wiring part, 40 ... elasticity Body, 40a: upper surface, 40b: lower surface, 50: conductor, 60: detection unit, 70: touch panel, 75: operation unit, 80: base, 85: cushion, 90: housing, 100: panel, 100a: operation surface

Claims (6)

A substrate,
A first detection electrode formed on the bottom side of the substrate;
A ground electrode formed on the same surface as the first detection electrode so as to surround at least the periphery of the first detection electrode, and grounded;
An elastic body provided on the bottom side of the substrate;
A conductor formed on the surface of the elastic body opposite to the substrate;
Equipped with
A detection device in which a virtual ground state is generated by capacitive coupling between the ground electrode and the conductor. The second detection electrode is formed on the same surface as the first detection electrode without being in contact with the first detection electrode,
The detection device according to claim 1, wherein the ground electrode is formed to surround the first detection electrode and the second detection electrode. A detection unit that detects a capacitance between the first detection electrode and the second detection electrode;
The detection device according to claim 1, wherein the detection unit detects a load based on a change in capacitance due to a change in distance between the conductor and the bottom side sandwiching the elastic body.   The detection device according to claim 2 or 3, wherein each of the first detection electrode and the second detection electrode is formed in a comb shape and disposed so as to mesh with each other. A detection unit that detects a capacitance based on the self-capacitance of the first detection electrode;
The detection device according to claim 1, wherein the detection unit detects a load based on a change in capacitance due to a change in distance between the conductor and the bottom side sandwiching the elastic body. A detection device according to any one of claims 1 to 5;
An input device comprising a touch panel that detects capacitance and performs touch detection.

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