JP2016193668A - Grip detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grip detection device which can detect whether gripped or not based on a capacitance value.SOLUTION: A grip detection device includes: a steering wheel; a capacitance sensor mounted on an annular part of the steering wheel; and a determination part which determines whether a driver grips the steering wheel or not based on proximity detection of a human body by the capacitance sensor. The capacitance sensor includes: a first detection electrode; a second detection electrode which extends in a direction along the first detection electrode, is arranged apart from the first detection electrode, and is structured of an opposite part opposite to the first detection electrode and a non-opposite part which is not opposite to it; an insulating material which displaceably supports the first detection electrode and changes an interval between the first and second detection electrodes depending on pressing force; and a capacitance detection circuit connected to one of the first and second detection electrodes.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a grip detection device that detects grip of a steering wheel of an automobile or the like.

2. Description of the Related Art A grip detection device is known that mounts a capacitive sensor on a steering wheel of an automobile and detects the grip of the steering wheel by a driver based on the proximity detection of the human body by the capacitive sensor (for example, patent document) 1).
In the grip detection device described in Patent Literature 1, a capacitive touch panel is mounted on the annular portion of the steering wheel, and the total area of the detection electrodes that detect the proximity of the human body among a large number of detection electrodes constituting the capacitive touch panel. By determining that the driver is gripping the steering wheel when the above is equal to or greater than a predetermined value, erroneous detection of gripping due to driver's inadvertent contact is avoided.

JP 2013-75653 A

However, in the grip detection device disclosed in Patent Document 1, since the presence or absence of grip is determined based on the total area of the electrodes that have detected the proximity of the human body, the driver's arm etc. inadvertently contacts the steering wheel, When proximity of a human body is detected, there is a problem that it is erroneously detected as gripping.
When detecting the proximity of a human body with a capacitance sensor, the capacitance value detected by the detection electrode is large because the distance between the human body (finger, etc.) and the detection electrode hardly changes before and after gripping the steering wheel. Since the capacitance value does not change, and the capacitance value is likely to fluctuate due to environmental changes such as ambient temperature and humidity, it is difficult to determine the presence or absence of gripping based on the capacitance value of the detection electrode.

  The present invention has been made in view of the above-described problems, and provides a grip detection device capable of detecting the presence or absence of grip (pressing contact) of a steering wheel based on a detected capacitance value. It is aimed.

  The grip detection device according to the present invention includes a steering wheel, a capacitance sensor mounted on an annular portion of the steering wheel, and a driver gripping the steering wheel based on proximity detection of a human body by the capacitance sensor. And a determination unit that determines whether or not the electrostatic capacitance sensor extends in a direction along the first detection electrode and the first detection electrode, and the first detection electrode A second sensing electrode, which is a second sensing electrode that is spaced apart from the second sensing electrode, the second sensing electrode comprising a facing part facing the first sensing electrode and a non-facing part not facing the first sensing electrode, and the first sensing electrode being displaceable An insulating material that supports and changes an interval between the first and second detection electrodes according to a pressing force, and a capacitance detection circuit connected to one of the first and second detection electrodes. And

According to the grip detection device of the present invention, when the driver does not grip the steering wheel (inadvertent contact, etc.), only one of the first and second detection electrodes is connected to the capacitance detection circuit. Has been. When the driver holds the steering hole (pressing contact), the first detection electrode comes into contact with the second detection electrode by an insulating material that supports the first detection electrode so as to be displaceable, and the first and second detection electrodes are Connected to the capacitance detection circuit. And since the 2nd sensing electrode has a non-opposing part which does not oppose the opposing part which opposes the 1st sensing electrode, if the connection state to the electrostatic capacitance detection circuit of each sensing electrode changes, a human body (finger etc.) The electrode area for detecting the capacitance between them changes.
For this reason, there is a large difference in the detection value (capacitance value) output from the capacitance detection circuit before and after the driver grips (presses contact) the steering wheel. It is possible to determine the presence or absence of contact), and prevent erroneous detection due to driver's careless contact.

In the gripping detection device, the capacitance sensor may be configured such that the capacitance detection circuit is connected to the first detection electrode, and the first detection electrode is brought into contact with the opposing portion, whereby the first detection electrode is The second detection electrode may be connected to the capacitance detection circuit.
In this case, when the driver does not grip the steering wheel (inadvertent contact or the like), only the first detection electrode is connected to the capacitance detection circuit, and the detection value (electrostatic capacitance) output from the capacitance detection circuit. (Capacitance value) depends only on detection by the first detection electrode. When the steering wheel is held (pressed contact), not only the first detection electrode but also the second detection electrode is connected to the capacitance detection circuit via the first detection electrode, and is output from the capacitance detection circuit. The detected value (capacitance value) depends on the detection by the first and second detection electrodes. For this reason, after gripping the steering wheel, the electrode area for detecting the capacitance with the human body (finger, etc.) increases, and the detection value (capacitance value) output from the capacitance detection circuit is large. A difference (increase) occurs, and it is possible to determine the presence or absence of contact based only on the capacitance value.

In the grip detection device, the insulating material of the capacitance sensor may be a flexible film that supports the first detection electrode. Accordingly, the flexible film can be bent by the pressing contact of the object, and the first detection electrode can be brought into contact with the opposing portion of the second detection electrode. And a spacer interposed between the second detection electrodes. Thereby, the spacer can be compressed and deformed by the pressing contact of the object, and the first detection electrode can be brought into contact with the opposing portion of the second detection electrode.

Further, in the above grip detection device, the first detection electrode of the capacitance sensor may be composed of a plurality of electrode pieces arranged in parallel at intervals. Accordingly, the second detection electrode can be configured such that the facing portion and the non-facing portion are mixedly arranged.
The plurality of electrode pieces may be configured to be commonly connected to one and connected to the capacitance detection circuit. As a result, the number of wires extending to the capacitance detection circuit can be reduced to one.
The capacitance detection electrode includes a first detection circuit and a second detection circuit, and the plurality of electrode pieces are connected to an electrode piece connected to the first detection circuit and the second detection circuit. The electrode pieces may be arranged alternately. Thereby, it is possible to determine whether or not the gripping (pressing contact) position moves, and it is possible to recognize a slide touch (slide gripping).

  In the gripping detection device, a plurality of recesses corresponding to the plurality of electrode pieces are formed on the surface of the second detection electrode of the capacitance sensor, and the plurality of electrode pieces are disposed inside the plurality of recesses. It may be configured to be arranged. Thus, each electrode piece is disposed so as to be surrounded by each recess, and the first detection electrode (electrode piece) is easily in contact with the second detection electrode when the steering wheel is gripped (pressed contact). Can do.

  ADVANTAGE OF THE INVENTION According to this invention, the holding | grip detection apparatus which can detect the presence or absence of the holding | grip (pressing contact) of a steering wheel based on the detected electrostatic capacitance value can be provided.

It is the schematic which shows the structure of the holding | grip detection apparatus which concerns on embodiment of this invention. It is the sectional view on the AA 'line of FIG. FIG. 3 is a schematic diagram of the grip detection device according to the first embodiment, and FIG. 3A is a schematic diagram illustrating a state in which a human body (finger or the like) is close to the steering wheel, and FIG. These are the schematic diagrams which show the state by which the steering wheel was hold | gripped. FIG. 4 is a plan view of components of the capacitance sensor used in the second gripping device, FIG. 4A is a plan view of the first electrode substrate, and FIG. FIG. 4C is a plan view of the second electrode substrate, and FIG. 4C is a plan view of the spacer. FIG. 5 is a graph for explaining the operation of the capacitance sensor used in the grip detection device. FIG. 6 is a schematic diagram illustrating a configuration of the grip detection device according to the second embodiment. FIG. 7 is a schematic diagram illustrating a configuration of the grip detection device according to the third embodiment. FIG. 8 is a schematic diagram illustrating a configuration of the grip detection device according to the fourth embodiment. FIG. 9 is a plan view of components of the capacitance sensor according to the fourth embodiment, FIG. 9A is a plan view of a first electrode substrate, and FIG. 9B is a second view. FIG. 9C is a plan view of the spacer, and FIG. 9C is a plan view of the spacer. FIG. 10 is a schematic diagram illustrating a configuration of the grip detection device according to the fifth embodiment.

[First Embodiment]
Hereinafter, the grip detection apparatus 100 according to the first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic view of a grip detection device 100 according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of an annular portion 110 viewed in the AA ′ direction of FIG.
FIG. 3 is a schematic diagram showing the configuration of the grip detection device 100 according to the first embodiment. The cross-sectional view of the capacitance sensor 1, the capacitance detection circuit 2 connected to the capacitance sensor 1, and FIG. 3 is a block diagram showing an arithmetic circuit 3. FIG. 3A is a diagram showing a state in which a human body (finger or the like) is in proximity to the steering hole 110, and FIG. 3B is a diagram in which the driver grips (presses contact) the steering wheel 110. FIG.
4 is a plan view of components of the capacitance sensor 1, FIG. 4 (a) is a plan view of the first electrode substrate 10, and FIG. 4 (b) is a diagram of the second electrode substrate 20. FIG. 4C is a plan view of the spacer 30 interposed between the first and second detection electrodes.
Further, FIG. 5 is a graph for explaining the operation of the capacitance sensor used in the grip detection device. The distance between the capacitance sensor 1 and a human body (such as a finger) and the output of the capacitance sensor 1. It is a graph which shows the relationship with a value (electrostatic capacitance value).

  As shown in FIG. 1, a grip detection device 100 according to an embodiment of the present invention includes a steering wheel 110, a capacitance sensor 1 mounted on an annular portion 101 of the steering wheel 110, and a human body using the capacitance sensor 1. And a determination unit 3 that determines whether the driver has gripped the steering wheel based on the proximity detection. The capacitance sensor 1 disposed in the annular portion 101 is connected to the capacitance detection circuit 2 and the determination unit 3 disposed in the central portion 102 inside the annular portion 101 via the wiring portion 23.

FIG. 2 is a cross-sectional view of the annular portion 101 viewed in the AA ′ direction in FIG. 1. A central portion of the annular portion 101 is a steering core 101a. The capacitance sensor 1 is arranged along the outer peripheral surface of the steering core 101a.
When the capacitance sensor 1 is wound around the steering core 101a, irregularities may be generated on the surface of the annular portion 101. Such irregularities can be reduced by covering with the cushioning material 101b, and the outer periphery of the cushioning material 101b. Covered with a steering skin 101c such as leather. In addition, it can be considered that each layer is bonded with, for example, a double-sided adhesive tape or an adhesive.

  Next, the grip detection device 100 and the capacitance sensor 1 according to the present embodiment will be described. FIG. 3 is a schematic diagram illustrating a configuration of the grip detection device 100 according to the first embodiment. The grip detection device 100 according to the present embodiment is detected from a capacitance sensor 1 that detects the proximity of a human body (such as a finger), a capacitance detection circuit 2 that detects capacitance, and detected capacitance. And a determination unit 3 that determines the proximity and contact of the target. The capacitance detection circuit 2 and the determination unit 3 can be realized by an analog circuit, or can be realized by a calculation unit such as a microcomputer or a CPU.

  As shown in FIGS. 3A and 3B, the grip detection device 100 according to this embodiment includes a capacitance sensor 1 and a wiring portion 23 having first and second detection electrodes 11, 21 arranged to face each other. The capacitance detection circuit 2 is connected to the capacitance sensor 1 via the capacitor and detects the capacitance between the human body and the capacitance sensor 1. The capacitance detection circuit 2 is connected to the capacitance detection circuit 2. And a determination unit 3 that determines whether or not the steering wheel 110 is gripped based on a detection value (capacitance value) output from the detection circuit 2.

  The capacitance sensor 1 includes a first electrode substrate 10 having a first detection electrode 11 and a flexible film 12, a second electrode substrate 20 having a second detection electrode 21 and a flexible film 22, and the first And a spacer 30 interposed between the second electrode substrates 10 and 20.

As shown in FIG. 3A, the spacer 30 supports the electrode substrates 10 and 20 with the first and second detection electrodes 11 and 21 being separated from each other. Note that only the first detection electrode 11 (electrode pieces 111 to 115) of the first electrode substrate 10 is connected to the capacitance circuit 23 via the wiring portion 23. Therefore, when a human body (finger or the like) comes close to the steering wheel (capacitance sensor 1), the capacitance detection circuit 2 is connected to the first detection electrode 11 (electrode pieces 111 to 115) and the human body (finger or the like). In between, the capacitance is detected.
That is, the capacitance sensor 1 detects the proximity of the driver's finger or the like only with the first detection electrode 11.

  As shown in FIG. 3B, when the driver grips (presses contact) the steering wheel, the spacer 30 is compressed and deformed by the pressing force by the grip, and the first detection electrode 11 (electrode pieces 111 to 115) is displaced. Thus, the first and second detection electrodes 11 and 21 are configured to come into contact (contact) with the second detection electrode 21 and to be electrically connected. As a result, the capacitance detection circuit 2 that is connected only to the first detection electrode 11 via the wiring portion 23 is also connected to the second detection electrode 21 via the first detection electrode 11. Therefore, when the driver grips (presses and contacts) the steering wheel 1, the capacitance sensor 1 detects the proximity of the human body (such as a finger) with the first and second detection electrodes 11 and 21.

That is, the capacitance sensor 1 according to the present embodiment has a human body before and after the driver grips (presses and contacts) the steering wheel by the compression deformation of the spacer 30 interposed between the first and second electrode substrates 10. The area of the detection electrode for detecting the capacitance between the finger and the like is changed.
The first detection electrode 11 is composed of a plurality of electrode pieces 111 to 115. The second sensing electrode 21 is composed of a plurality of facing portions 211 to 215 that face the electrode pieces 111 to 115 of the first sensing electrode 11, respectively, and a non-facing portion 220 that does not face each other. The facing portions 211 to 215 function as contact points with the first detection electrode 11. Further, the non-opposing portion 220 serves as a detection electrode for detecting the capacitance between the first detection electrode 11 and the human body (such as a finger) when the first and second detection electrodes 11 and 12 are connected. Function.

  Next, the first and second electrode substrates 10 and 20 and the spacer 30 constituting the capacitance sensor 1 will be described in detail with reference to FIG.

  As shown in FIG. 4A, the first electrode substrate 10 includes a flexible film 12, and a first detection electrode 11 including a plurality of electrode pieces 111 to 115 formed on the flexible film 12, Each of the electrode pieces 111 to 115 is connected in common and is composed of a wiring portion 23 extending to a capacitance detection circuit (not shown). In the present embodiment, five rectangular electrode pieces 111 to 115 are formed on the flexible film 12. The electrode pieces 111 to 115 are arranged in a row at intervals along the short direction of the electrode pieces.

As shown in FIG. 4B, the second electrode substrate 20 includes a flexible film 22 and a rectangular second detection electrode 21 formed on the flexible film 22.
When the first and second electrode substrates 10 and 20 are overlapped with the first and second detection electrodes 11 and 21 facing each other, the second detection electrode 21 has a size facing all the electrode pieces 111 to 115. Is formed.

  Further, on the surface of the second detection electrode 21, recesses 210 are respectively formed in facing portions 211 to 215 facing the electrode pieces 111 to 115 of the first detection electrode 11, and the electrode pieces 111 to 115 are placed in the recesses 210. It is configured so that it can be placed. By configuring each electrode piece 111-115 to be disposed in each recess 210, three sides of each electrode piece 111-115 are surrounded by the recess 210, and the driver's steering wheel grip (capacitance sensor 1) The electrode pieces 111 to 115 of the first detection electrode 11 and the opposing portions 211 to 215 of the second detection electrode 21 are likely to come into contact (contact) from multiple directions according to the pressure).

Further, the second detection electrode 21 is formed with non-opposing portions 220 that do not oppose the electrode pieces 111 to 115 of the first detection electrode 11 around the opposing portions 211 to 215 (recesses 210).
And at least 1 of each electrode piece 111-115 contacts (contact | abuts) the opposing parts 211-215, and in the 2nd detection electrode 21, the electrostatic capacitance between human bodies (finger etc.) in the non-opposing part 220. It is comprised so that it may detect. That is, according to the area of the non-facing portion 220, the electrode area for detecting the capacitance between the human body (eg, a finger) after the steering wheel is gripped increases.

  For the flexible films 12 and 22 of the first and second electrode substrates 10 and 20, an insulating resin film such as polyethylene phthalate can be used. Further, the first detection electrode 11 (electrode pieces 111 to 115), the second detection electrode 21 and the wiring portion 23 can be formed on the flexible films 12 and 22 by screen printing silver paste or the like. Further, the concave portion 210 can be formed on the surface of the second detection electrode 21 by repeating screen printing such as silver paste a plurality of times.

As shown in FIG. 4C, the spacer 30 interposed between the first and second electrode substrates 10 and 20 is opened at a position corresponding to the recesses (opposing portions 211 to 215) of the second detection electrode 21. 31-35 are formed.
The spacer 30 is made of, for example, an insulating resin material such as polyethylene terephthalate, is compressed and deformed by a pressing force, displaces the interval between the first and second detection electrodes, and the first detection electrode via the openings 31 to 35. The eleven electrode pieces 111 to 115 and the opposing portions 211 to 215 of the second detection electrode 2 can be brought into contact (contact).

Next, with reference to FIG. 5, the operation of the capacitance sensor 1 used in the grip detection device according to the present embodiment will be described. FIG. 5 is a graph showing the relationship between the distance between the human body (finger) and the capacitance sensor 1 and the capacitance value detected by the capacitance sensor 1.
As described above, when the human body (finger or the like) is in proximity to the capacitance sensor 1, only the first detection electrode 11 (electrode pieces 111 to 115) is connected to the capacitance detection circuit 2. Further, in a state where the driver grips (presses contact) the steering wheel and presses the capacitance sensor, the spacer 30 is compressed and deformed according to the pressing force, and the first detection electrode 11 (at least one of the electrode pieces 111 to 115). Are in contact (electrically connected) with the second detection electrode 21 (opposing portions 211 to 215). As a result, the first and second detection circuits are connected to the capacitance detection circuit 2, and not only the capacitance between the first detection electrode 11 and the human body (finger etc.) but also the human body (finger etc.) and the first The electrostatic capacitance between the two sensing electrodes 21 is also detected. That is, before and after the steering wheel is gripped, the electrode area for detecting the capacitance with the human body (such as a finger) changes.
Therefore, as shown in the graph of FIG. 5, the detection value (static value) output from the capacitance detection circuit before and after the driver holds the steering wheel (pressing contact) and the capacitance sensor 1 is pressed. A large difference occurs in the capacitance value), and it is possible to determine the presence or absence of gripping (pressing contact) only by the capacitance value.

[Second Embodiment]
Next, a grip detection device 100a according to a second embodiment of the present invention will be described with reference to FIG. Here, differences from the first embodiment will be described, and in FIG. 6, components having the same aspects as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.
The grip detection device 100a according to the present embodiment is that the concave portion is not formed on the surface of the second detection electrode 21 of the second electrode substrate 20a in the capacitance sensor 1a. Is different. Moreover, the thickness of the spacer 30 is thicker than in the first embodiment.

Also in this embodiment, as in the first embodiment, only the first detection electrode 11 (electrode pieces 111 to 115) is connected to the capacitance detection circuit 2 in a state where a human body (finger) or the like is close to the steering wheel. ing. Further, in a state where the steering wheel is gripped (pressed contact) and the capacitance sensor 1 is pressed, the spacer 30a is compressed and deformed, and at least one of the electrode pieces 111 to 115 of the first detection electrode 11 is subjected to the second detection. The first and second detection electrodes 11 and 21 are connected to the capacitance detection circuit 2 in contact with (contact with) the electrode 21 (opposing portions 211 to 215). Therefore, not only the capacitance between the first detection electrode 11 and the human body (finger etc.) but also the capacitance between the human body (finger etc.) and the second detection electrode 21 is detected. Thereby, the effect similar to the holding | grip detection apparatus 100 of 1st Embodiment can be acquired.
In the present embodiment, the second detection substrate 20a can be easily manufactured by not forming the concave portion on the surface of the second detection electrode 21.
[Third Embodiment]

Next, a grip detection device 100b according to a third embodiment of the present invention will be described with reference to FIG. Here, differences from the first embodiment will be described, and in FIG. 7, the same reference numerals are given to components having the same aspects as those of the above-described embodiment, and description thereof will be omitted.
The grip detection device 100b according to the present embodiment is different from the first embodiment in that no spacer is interposed between the first and second electrode substrates 10a and 20 of the capacitance sensor 1b. The flexible film 12 of the first electrode substrate 10a is formed with a plurality of curved portions 12a to 12e, and the electrode portions 111 to 115 are provided on the curved portions 12a to 12e.

Also in this embodiment, as in the first embodiment, only the first detection electrode 11 (electrode pieces 111 to 115) is connected to the capacitance detection circuit 2 in a state where a human body (finger or the like) is close to the steering wheel. ing. When the steering wheel is gripped (pressed contact) and the capacitance sensor 1b is pressed, at least one of the curved portions 12a to 12e of the flexible film 12 is bent and deformed. As a result, the electrode piece on the curved portion contacts (contacts) the second detection electrode 21 (opposing portions 211 to 215), and the first and second detection electrodes 11 and 21 are connected to the capacitance detection circuit 2. The For this reason, not only the electrostatic capacitance between the first detection electrode 11 and the human body (finger etc.) but also the electrostatic capacitance between the human body (finger etc.) and the second detection electrode 21 is detected. Thereby, the effect similar to the holding | grip detection apparatus 100 of 1st Embodiment can be acquired.
In this embodiment, since no spacer is used, the number of parts can be reduced.
[Fourth Embodiment]

Next, a grip detection device 100c according to a fourth embodiment of the present invention will be described with reference to FIGS. Here, differences from the first embodiment will be described, and in FIG. 8 and FIG. 9, constituent elements having the same aspects as those of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.
The grip detection device 100c according to the present embodiment is different from the grip detection device 100 according to the first embodiment in that the capacitance detection circuit 2 includes first and second detection circuits 2a and 2b. Of the electrode pieces 111 to 115 of the first electrode substrate 10b of the capacitance sensor 1c, three electrode pieces 111, 113, 115 are connected to the first detection circuit 2a via the wiring portion 23a, The point that the electrode pieces 112 and 114 are connected to the detection circuit 2b is different from the capacitance sensor 120 of the first embodiment.

  In the present embodiment, similarly to the first embodiment, only the first detection electrode 11 (electrode pieces 111 to 115) is electrostatic in a state where a human body (finger or the like) is close to the steering wheel (capacitance sensor 1c). The capacitance detection circuit 2 is connected to the first detection circuit 2a or the second detection circuit 2b. Further, in a state where the steering wheel is gripped (pressed contact) and the capacitance sensor 1c is pressed, the spacer 30 is compressed and deformed, and at least one of the electrode pieces 111 to 115 of the first detection electrode 11 is subjected to the second detection. The first and second detection electrodes 11 and 21 are connected to the capacitance detection circuit 2 in contact with (contact with) the electrode 21 (opposing portions 211 to 215). Therefore, after gripping the steering wheel, not only the capacitance between the first detection electrode 11 and the human body (finger etc.) but also the capacitance between the human body (finger etc.) and the second detection electrode 21. Is also detected. Thereby, the effect similar to the holding | grip detection apparatus 100 of 1st Embodiment can be acquired.

Further, in the present embodiment, among the five electrode pieces 111 to 115, the electrode pieces 111, 113, 115 connected to the first detection circuit 2a and the electrode pieces 112, 114 connected to the second detection circuit 2b are alternately arranged. Therefore, it is possible to determine whether or not the gripping position (pressing contact) moves, and it is possible to recognize a slide touch (slide gripping).
[Fifth Embodiment]

Next, a grip detection device 100d according to a fifth embodiment of the present invention will be described with reference to FIG. Here, differences from the first embodiment will be described, and in FIG. 10, constituent elements having the same aspects as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.
The grip detection device 100d according to the present embodiment is that the second detection electrode 21 is connected to the capacitance detection circuit 2 instead of the first detection electrode 11 of the capacitance sensor 1d. Different from the detection device 100.

In the present embodiment, only the second detection electrode 21 is connected to the capacitance detection circuit 2 in a state where a human body (finger or the like) is close to the steering wheel (capacitance sensor 1d). At this time, since the first detection electrode 11 (electrode pieces 111 to 115) is interposed between the facing portions 211 to 215 of the second detection electrode 21 and the human body (finger or the like), the non-facing portion 220 and the human body (finger Etc.) is detected.
Further, in a state where the steering wheel is gripped (pressed contact) and the capacitance sensor 1d is pressed, the spacer 30 is compressed and deformed, and at least one of the electrode pieces 111 to 115 of the first detection electrode 11 is detected by the second detection. The first and second detection electrodes 11 and 21 are connected to the capacitance detection circuit 2 in contact with (contact with) the electrode 21 (opposing portions 211 to 215). Thereby, not only the electrostatic capacitance between the non-opposing portion 220 of the second detection electrode and the human body (finger etc.) but also the electrostatic capacitance between the human body (finger etc.) and the first detection electrode 11 is detected. The For this reason, when the steering wheel is gripped (pressed contact), the electrode area for detecting a human body (such as a finger) increases, and the same effect as the grip detection device 100 of the first embodiment can be obtained. .

The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 1,1a-1d ... Capacitance sensor, 2 ... Capacitance detection circuit, 2a ... 1st detection circuit, 2b ... 2nd detection circuit, 3 ... Arithmetic circuit 10, 10a, 10b ... 1st electrode substrate, 11 ... 1st detection electrode, 111-115 ... Electrode piece, 12 ... Flexible film, 20, 20a ... 2nd electrode substrate, 21 ... 2nd detection electrode, 210 ... Recessed part, 211-215, 211a-215a ... Opposite part , 220, 220a ... non-opposing parts, 30, 30a ... spacers, 23, 23a to 23b ... wiring parts, 100, 100a to 100d ... grip detection devices

Claims (8)

A steering wheel,
A capacitance sensor mounted on the annular portion of the steering wheel;
A determination unit that determines whether or not the driver has gripped the steering wheel based on proximity detection of the human body by the capacitance sensor,
The capacitance sensor
A first sensing electrode;
A second sensing electrode that extends in a direction along the first sensing electrode and is spaced apart from the first sensing electrode, and a non-facing portion that does not face the facing portion facing the first sensing electrode; A second sensing electrode comprising:
An insulating material that supports the first detection electrode in a displaceable manner and changes an interval between the first and second detection electrodes according to a pressing force;
And a capacitance detection circuit connected to one of the first and second detection electrodes. In the capacitance sensor,
The capacitance detection circuit is connected to the first detection electrode,
The said 2nd sensing electrode is connected to the said electrostatic capacitance detection circuit via the said 1st sensing electrode when the said 1st sensing electrode contacts the said opposing part. Grasping detection device. In the capacitance sensor,
The grip detection device according to claim 1, wherein the insulating material is a flexible film that supports the first detection electrode. In the capacitance sensor,
The grip detection device according to claim 1, wherein the insulating material is a spacer interposed between the first and second detection electrodes. In the capacitance sensor,
The grip detection device according to any one of claims 1 to 4, wherein the first detection electrode includes a plurality of electrode pieces arranged in parallel at intervals. In the capacitance sensor,
The grip detection device according to claim 5, wherein the plurality of electrode pieces are connected in common to one another and connected to the capacitance detection circuit. The capacitance detection circuit includes first and second detection circuits,
The grip detection device according to claim 5, wherein the plurality of electrode pieces are alternately arranged with electrode pieces connected to the first detection circuit and electrode pieces connected to the second detection circuit. A plurality of concave portions corresponding to the plurality of electrode pieces are formed on the surface of the second detection electrode,
The plurality of electrode pieces are disposed inside the plurality of recesses. The grip detection device according to any one of claims 5 to 7.

Images