Electrostatic capacitance type input device and electrostatic capacitance type input method

Abstract

Provided is an electrostatic capacitance input device and an electrostatic capacitance input method capable of determining which of a plurality of touch switches has been subjected to a touch operation. The electrostatic capacitance input device includes: a plurality of touch switches; and a determination section that determines a touch operation to one of the plurality of touch switches based on outputs of the plurality of touch switches; the determination section performs a first comparison of comparing a first threshold value used in determining the presence or absence of the touch operation to the outputs of the plurality of touch switches; performs a second comparison of comparing outputs of the plurality of touch switches that are greater than the first threshold value to a plurality of comparison threshold values that are greater than the first threshold value and different from each other; and determines a touch operation to one of the plurality of touch switches based on comparison results obtained in the first comparison or the second comparison.

Description

Technical Field

[0001] This invention relates to an electrostatic capacitive input device and an electrostatic capacitive input method. Background Technology

[0002] Conventional capacitive touch switch devices include touch electrodes, a touch detection circuit, and a threshold setting circuit. The touch detection circuit outputs a touch detection signal indicating the presence or absence of a touch, and the threshold setting circuit supplies a threshold setting signal to the touch detection circuit to set a threshold value. The threshold is set lower during the touch operation phase and higher after the touch operation is received, thus accelerating the response to the touch operation (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-063802 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] Incidentally, if the threshold designation circuit of the conventional electrostatic capacitive touch switch device is applied to multiple touch switches arranged adjacently, the threshold during the touch operation acceptance phase is very low, so it will be judged that a touch operation has been performed on multiple touch switches at the same time, making it difficult to determine which of the multiple touch switches has been touched.

[0008] Therefore, the object of the present invention is to provide an electrostatic capacitive input device and an electrostatic capacitive input method capable of determining which of a plurality of touch switches has been touched.

[0009] Methods for solving technical problems

[0010] An electrostatic capacitive input device according to an embodiment of the present invention includes: a plurality of touch switches; and a determination unit that determines a touch operation on one of the plurality of touch switches based on the outputs of the plurality of touch switches; the determination unit performs a first comparison comparing a first threshold used in determining the presence or absence of the touch operation with the outputs of the plurality of touch switches respectively; performs a second comparison comparing an output of the plurality of touch switches that is larger than the first threshold with a plurality of comparison thresholds that are larger than the first threshold and are different from each other; and determines a touch operation on one of the plurality of touch switches based on the comparison result obtained in the first comparison or the second comparison.

[0011] Invention Effects

[0012] This invention provides an electrostatic capacitive input device and an electrostatic capacitive input method capable of determining which of a plurality of touch switches has been touched. Attached Figure Description

[0013] Figure 1 This is a diagram showing a steering wheel 10 with an operation section 110 of an electrostatic capacitive input device according to an embodiment.

[0014] Figure 2 This is a diagram illustrating the electrostatic capacitive input device 100 according to an embodiment.

[0015] Figure 3 This is a diagram showing the distribution of electrostatic capacitance of touch switches 111 to 119 when touch switches 114 and 115 are touched respectively.

[0016] Figure 4 It indicates that... Figure 3 (A) Figure 3 The bar graph of electrostatic capacitance from row 8 to row 10 in the region of (B) with 20 rows x 24 columns.

[0017] Figure 5 It indicates that... Figure 3 (A) Figure 3 The bar graph of electrostatic capacitance from row 11 to row 13 in the region of (B) with 20 rows x 24 columns.

[0018] Figure 6 This is a diagram illustrating the decision-making process used for comparison.

[0019] Figure 7 This is a diagram illustrating the threshold used in the determination process of the electrostatic capacitive input device 100 in the embodiment.

[0020] Figure 8 This diagram illustrates the determination process performed by the determination unit 123 in the embodiment.

[0021] Figure 9 This is a flowchart illustrating the decision process performed by the decision unit 123.

[0022] Figure 10 This is a flowchart showing the detailed processing of step S4.

[0023] Figure 11 This is a flowchart showing the detailed processing of step S5.

[0024] Figure 12 This is a graph showing the relationship between the distribution of electrostatic capacitance and the first threshold (1), the second threshold (2), and the third threshold (3). Detailed Implementation

[0025] The embodiments of the electrostatic capacitive input device and electrostatic capacitive input method of the present invention will be described below.

[0026] <Implementation Method>

[0027] Figure 1 This diagram shows a steering wheel 10 equipped with an operation section 110 of the electrostatic capacitive input device according to the embodiment. The steering wheel 10 is located in the driver's seat of a vehicle, and the operation section 110 is provided on the wheel spokes. Figure 1 In the example shown, the operation unit 110 is operated by the thumb of the user's right hand H.

[0028] A vehicle is a motor vehicle that can move on a road using an engine and / or motor as its power source. Vehicles may also be equipped with various levels of automated driving functions as defined by the Society of Automotive Engineers (SAE) International in the United States.

[0029] As shown in the enlarged view, the operation unit 110 has nine touch switches 111 to 119 as an example. In the enlarged view showing the touch switches 111 to 119, the cover that covers the touch switches 111 to 119 is omitted. The touch switches 111 to 119 are an example of multiple touch switches. Here, the areas where the touch switches 111 to 119 are arranged are described as (1) to (9).

[0030] Touch switches 111-119 are housed in housing 110A for mounting... Figure 1 The cover 110B covering the front operating surface is set on the spokes of the steering wheel 10.

[0031] Touch switches 111-119 are arranged in a roughly matrix-like configuration of 3 rows x 3 columns. Touch switches 111-119, as an example, are electrodes made of metal foil, metal plate, or conductive film, and are connected to a control device (not shown) via wiring or cables. Touch switches 111-119 and hand H (see reference) Figure 1 The electrostatic capacitance between the hands (H) and touch switches 111 to 119 varies depending on the proximity (distance) of the hand H to the touch switches 111 to 119.

[0032] Touch switches 111-119 are used, as an example, to operate various electronic devices in a vehicle. By touching a portion of the surface of a touch switch 111-119 within the (touch) cover 110B with a fingertip, desired electronic devices in the vehicle can be operated. Functions of electronic devices operable by touch switches 111-119 include, for example, selecting audio tracks or adjusting volume, selecting whether to hang up or end a hands-free call, or setting cruise control.

[0033] Figure 2 This is a diagram illustrating an electrostatic capacitive input device 100 according to an embodiment. The electrostatic capacitive input device 100 includes an operation unit 110 and a control unit 120. The operation unit 110 has touch switches 111-119 (see reference). Figure 1 ), but Figure 2 (The text is omitted.) As an example, the electrostatic capacitive input device 100 detects touch operations to touch switches 111-119 by means of self-capacitance.

[0034] The operating unit 110 and the control device 120 are connected via wiring or cables. The control device 120 is, for example, mounted on the steering wheel 10 and integrally formed with the operating unit 110. However, while the configuration where the control device 120 is mounted on and integrally formed with the operating unit 110 is described here, the control device 120 can also be separately formed from the operating unit 110 and located outside the steering wheel 10 within the vehicle's interior.

[0035] The control unit 120 is connected to the ECU (Electronic Control Unit) 50, which controls electronic devices, via an in-vehicle network such as CAN (Controller Area Network) or LIN (Local Interconnect Network). The ECU 50 is an electronic control unit that controls the vehicle's audio, hands-free phone, cruise control, and other electronic devices. Figure 2 One ECU 50 is shown, but multiple ECUs 50 can also be connected to the control unit 120.

[0036] The control device 120 is implemented by a computer including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), input / output interfaces, and internal bus.

[0037] The control device 120 includes a main control unit 121, an electrostatic capacitance detection unit 122, a determination unit 123, and a memory 124. The main control unit 121, the electrostatic capacitance detection unit 122, and the determination unit 123 represent the functions of the program executed by the control device 120 as function blocks. In addition, the memory 124 functionally represents the memory of the control device 120.

[0038] The main control unit 121 is a processing unit that comprehensively performs the control processing of the control device 120, and performs processing other than that performed by the electrostatic capacitance detection unit 122 and the determination unit 123.

[0039] Electrostatic capacitance detection unit 122 detects touch switches 111-119 (refer to) Figure 1 The electrostatic capacitance of touch switches 111-119 is recorded, and the count value of the electrostatic capacitance of each touch switch 111-119 is transmitted to the determination unit 123. The count value of the electrostatic capacitance is the change relative to a reference value when the touch switches 111-119 are not operated; it is the difference obtained by subtracting the reference value from the electrostatic capacitance during operation. Hereinafter, the electrostatic capacitance is the difference relative to the reference value. The electrostatic capacitance of touch switches 111-119 is an example of the output of touch switches 111-119. In each of touch switches 111-119, one count value representing the electrostatic capacitance of each touch switch 111-119 can be obtained.

[0040] The determination unit 123 determines, based on the electrostatic capacitance count values ​​of each of the touch switches 111-119 transmitted from the electrostatic capacitance detection unit 122, that a touch operation has been performed on one of the touch switches 111-119. The determination result of the determination unit 123 indicates which touch switch among touch switches 111-119 was touched. The determination result of the determination unit 123 is the detection result of which touch switch was touched, as detected by the electrostatic capacitance input device 100. The determination process performed by the determination unit 123 will be described later.

[0041] The memory 124 stores programs and data required for the control device 120 to perform decision processing. The memory 124 stores data that represents the count values ​​of the electrostatic capacitance of each of the touch switches 111 to 119, as well as data generated by the decision unit 123 during the decision processing.

[0042] Here, there are various requirements regarding the sensitivity of the capacitive input device 100 in detecting touch operations performed on touch switches 111-119. For example, when the capacitive input device 100 is installed in a vehicle designed for use in cold weather, there may be cases where gloves are worn when operating the steering wheel 10 and the control unit 110. In such cases, since the count value of the electrostatic capacitance of each of the touch switches 111-119 tends to decrease, the threshold value in the determination process of the determination unit 123 is lowered. This is to improve the sensitivity of detecting touch operations performed while wearing gloves. However, if the threshold value is lowered, in addition to the count value obtained from the touch switch that has been touched, the count value obtained from adjacent touch switches may also exceed the threshold value, so careful design is required.

[0043] As a result of this careful design, in the determination process of the determination unit 123 in the embodiment, in order to determine that the touch switch that has been touched is one of the touch switches 111 to 119, it is easy to use three or more (three stages or more) thresholds to compare the electrostatic capacitance of adjacent touch switches. Here, before explaining the determination process of the determination unit 123 in the embodiment, we will use Figures 3 to 6 The comparison determination process is explained. In the comparison determination process, two (two-stage) thresholds are used to determine that the touch switch that has been touched is one of touch switches 111 to 119.

[0044] Figure 3 This is a diagram showing the distribution of electrostatic capacitance of touch switches 111 to 119 when touch switches 114 and 115 are touched respectively. Figure 3 (A) indicates the distribution of electrostatic capacitance of touch switches 111-119 when a touch operation is performed on the central part of touch switch 114. Figure 3 (B) indicates the distribution of electrostatic capacitance of touch switches 111-119 when a touch operation is performed on the central part of touch switch 115. Electrostatic capacitance is represented by a count value.

[0045] exist Figure 3 (A) Figure 3 In (B), as an example, the rectangular area encompassing the entire surface of touch switches 111-119, viewed from above, is divided into 480 regions at 3mm intervals, arranged in 20 rows x 24 columns. The 480 electrostatic capacitances obtained from analyzing these 480 regions are described. While each of the actual touch switches 111-119 yields a single count representing the electrostatic capacitance, here, for a more detailed analysis of the capacitance distribution, the 480 electrostatic capacitances obtained from analyzing these 480 regions are described. More specifically, in... Figure 3 (A) represents the output of touch switch 114. Figure 3 The output of touch switch 114 in (A) is the output of touch switch 114 when touch operations are performed on 480 areas respectively. Similarly, in Figure 3 (B) indicates the output of touch switch 115. Figure 3 The output of touch switch 115 in (B) is the output of touch switch 115 when touch operation is performed on 480 areas respectively.

[0046] exist Figure 3 In (A), when touch operations were performed on 480 areas, the output capacitance of the touch switch 114 increased when the touch operation occurred in the central area of ​​the touch switch 114, and decreased when the touch operation occurred in areas away from the central area of ​​the touch switch 114. This is related to... Figure 3 The same applies to the touch switch 115 in (B).

[0047] In addition, Figure 3 (A) Figure 3 In (B), the area where the electrostatic capacitance exceeds the first threshold (1) is represented in gray. The first threshold (1) is a threshold for determining the presence or absence of touch operation based on the nine electrostatic capacitances actually obtained from touch switches 111 to 119. The first threshold (1) is a low value that allows for determining the presence or absence of touch operation even when the hand H is wearing gloves.

[0048] like Figure 3 As shown in (A), when touch operations are performed on 480 areas respectively, areas determined to have been touched based on the output of touch switch 114 and a first threshold (1) are outside the touch switch 114. That is, even if a touch operation is performed on an area located outside the touch switch 114 but near the touch switch 114, the output of touch switch 114 exceeds the first threshold. Similarly, as Figure 3 As shown in (B), when touch operations were performed on 480 areas respectively, the areas determined to have been touched based on the output of touch switch 115 and the first threshold (1) reached the outside of touch switch 115. That is, even if a touch operation was performed on an area located outside of touch switch 115 but near touch switch 115, the output of touch switch 115 exceeded the first threshold. The reason why the areas determined to have been touched based on the first threshold (1) reached the outside of touch switches 114 and 115 is that the first threshold (1) is a low value that can determine the presence or absence of touch operation even when the hand H is wearing gloves.

[0049] Therefore, if a touch operation is performed on the area of ​​touch switch 114, it may be determined that a touch operation was performed on touch switches 111, 112, 115, 117, and 118 adjacent to touch switch 114. The touch switches adjacent to touch switch 114 are those located horizontally, vertically, and diagonally beside touch switch 114. In other words, if a touch operation is performed on the area of ​​touch switches 111, 112, 115, 117, and 118 adjacent to touch switch 114, it may be determined that a touch operation was performed on touch switch 114 itself.

[0050] Similarly, when a touch operation is performed on touch switch 115, it may be determined that a touch operation was performed on touch switches 111, 112, 113, 114, 116, 117, and 118 adjacent to touch switch 115. The touch switches adjacent to touch switch 115 are those located horizontally, vertically, and diagonally adjacent to touch switch 115.

[0051] As mentioned above, it may be difficult to determine whether a touch operation was performed by one of the touch switches 111 to 119 based solely on the first threshold (1). Therefore, in the comparison determination process, a second threshold (2) with a value greater than the first threshold (1) is used.

[0052] Figure 4 It means to Figure 3 (A) Figure 3 The diagram (B) shows a bar chart representing the electrostatic capacitance from row 8 to row 10 within a 20x24 area. The electrostatic capacitance of touch switch 114 is represented by a white bar chart, and the electrostatic capacitance of touch switch 115 is represented by a black bar chart. Figure 4 In the middle, it represents horizontally. Figure 3 (A) Figure 3 The electrostatic capacitance from column 1 to column 24 in the 20-row x 24-column region of (B). Column 24 is the rightmost column in the 20-row x 24-column region.

[0053] In addition, Figure 4 In addition to the first threshold (1), the second threshold (2) is also represented. The second threshold (2) is higher than the first threshold (1). In the comparison determination process, when only one of the nine electrostatic capacitors actually obtained from the touch switches 111 to 119 exceeds the second threshold (2), it is determined that a touch operation was performed by the touch switch that obtained the electrostatic capacitor.

[0054] Thus, in the comparison determination process, in order to determine the touch switch that has been touched, a second threshold (2) larger than the first threshold (1) is used in addition to the first threshold (1). However, problems may occur if an electrostatic capacitance exceeding the second threshold (2) cannot be obtained. Regarding the method and problem of determining a touch switch that has been touched when no electrostatic capacitance exceeding the second threshold (2) exists in the comparison determination process, the following method is used... Figure 6 To be described later.

[0055] In row 8, the electrostatic capacitance cannot exceed the second threshold (2). In columns 10 to 12, which are surrounded by a square with dashed lines, touch switches 114 and 115 both exceed the first threshold (1).

[0056] In row 9, although the electrostatic capacitance exceeding the second threshold (2) can be obtained, in columns 10 and 11 surrounded by a square with dashed lines, touch switches 114 and 115 both exceed the first threshold (1), but neither exceeds the second threshold (2).

[0057] In row 10, although the electrostatic capacitance exceeding the second threshold (2) can be obtained, in columns 10 and 11 surrounded by a square with dashed lines, touch switches 114 and 115 both exceed the first threshold (1), but neither exceeds the second threshold (2).

[0058] Figure 5 It means to Figure 3 (A) Figure 3 The diagram is a bar graph representing the electrostatic capacitance from row 11 to row 13 in the region of (B) with 20 rows x 24 columns. Figure 5 The representation of electrostatic capacitance in [the context of the text] is different from [the representation of electrostatic capacitance in the context of the text]. Figure 4 The representation of electrostatic capacitance is the same as that in [the context of electrostatic capacitance].

[0059] In row 11, although the electrostatic capacitance exceeding the second threshold (2) can be obtained, in columns 10 to 12 surrounded by the dashed square, touch switches 114 and 115 both exceed the first threshold (1), but neither exceeds the second threshold (2).

[0060] In row 12, although the electrostatic capacitance exceeding the second threshold (2) can be obtained, in columns 9 to 12 surrounded by the dashed square, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).

[0061] In row 13, no electrostatic capacitance exceeding the second threshold (2) can be obtained. In columns 10 and 11, which are surrounded by a square with dashed lines, touch switches 114 and 115 both exceed the first threshold (1), but neither exceeds the second threshold (2).

[0062] like Figure 4 and Figure 5 As shown, even if the first threshold (1) and the second threshold (2) which is larger than the first threshold (1) are used, there are cases where the electrostatic capacitance of touch switches 114 and 115 cannot exceed the second threshold (2). Near the boundary of touch switches 114 and 115, a gray area becomes where it is impossible to determine which one has been touched.

[0063] Figure 6 This is a diagram illustrating the decision-making process used for comparison. Figure 6 (A) Figure 6 (C) shows simplified touch switches 114 and 115 and the electrostatic capacitance obtained by touch switches 114 and 115.

[0064] exist Figure 6 In (A), the electrostatic capacitance represents the state in which the fingertip FT touches an area of ​​touch switch 114 that is close to touch switch 115. Such a position of the fingertip FT may occur during the movement of the fingertip FT from touch switch 114 toward touch switch 115. The electrostatic capacitance of touch switch 114 exceeds a first threshold (1) but is less than a second threshold (2), and the electrostatic capacitance of touch switch 115 is lower than the electrostatic capacitance of touch switch 114, but exceeds the first threshold (1) and is less than the second threshold (2). In such a case, it is determined that the touch operation was performed on touch switch 114 whose electrostatic capacitance first exceeded the first threshold (1) in timing.

[0065] exist Figure 6 (B) represents the electrostatic capacitance of the fingertip FT touching touch switches 114 and 115. This situation may occur during the movement of fingertip FT from touch switch 114 towards touch switch 115, or during the movement of fingertip FT from the direction of touch switches 111 or 112, or from the direction of touch switches 117 or 118 towards touch switches 114 and 115. The electrostatic capacitance of both touch switches 114 and 115 exceeds the first threshold (1). In such cases, it cannot be determined which of touch switches 114 and 115 was touched.

[0066] exist Figure 6(C) represents the electrostatic capacitance when the fingertip FT touches touch switch 115 but does not touch touch switch 114. The electrostatic capacitance of touch switch 114 exceeds the first threshold (1) but is less than the second threshold (2), and the electrostatic capacitance of touch switch 115 exceeds the second threshold (2). In this case, it is determined that a touch operation has been performed on touch switch 115. However, this situation may vary depending on whether the electrostatic capacitance is different when wearing gloves or due to individual differences.

[0067] As described above, in the decision-making process using a two-stage threshold comparison based on two first thresholds (1) and second thresholds (2), such as Figure 6 As shown in (B), when the fingertip FT is located at the boundary between two touch switches, there is a problem that it is impossible to determine which of the two touch switches the touch operation was performed on. This problem occurs in... Figure 4 , Figure 5 The problem is more pronounced in the area enclosed by the square of the dashed line near the boundaries of touch switches 114 and 115, and it can occur at the boundaries of adjacent touch switches in all of touch switches 111 to 119.

[0068] Therefore, this problem is solved in the determination process of the determination unit 123 in the implementation method. Hereinafter, using... Figures 7 to 12 The determination process of the determination unit 123 in the embodiment will be described. In the determination process of the determination unit 123 in the embodiment, the touch switch that has been touched is determined by using at least three thresholds (a first threshold (1), a second threshold (2), and a third threshold (3)). The second threshold (2) and the third threshold (3) of the at least three thresholds are examples of multiple comparison thresholds, and are examples of multiple comparison thresholds that are larger than the first threshold and different from each other. In addition, the third threshold (3) is an example of the largest comparison threshold among the multiple comparison thresholds. In addition, the second threshold (2) is different from the second threshold (2) used for comparison described above. Details will be described later.

[0069] Figure 7 This is a diagram illustrating the threshold values ​​used in the determination process of the capacitive input device 100 in this embodiment. Figure 7 (A) and Figure 7 In (B), the area where the electrostatic capacitance exceeds the first threshold (1) when touch operation is performed on touch switches 114 and 115 is indicated in gray. That is, the gray area represents the area corresponding to the first threshold (1).

[0070] The first threshold (1) in the implementation method is the same as the first threshold (1) in the comparison determination process, and is a low value that allows the presence or absence of a touch operation to be determined even when the touch operation is performed by the fingertip FT of a gloved hand H. Such a first threshold (1) is when the hand H (refer to...) is an example of an operating body. Figure 1 When the outer edge or vicinity of the touch switch is operated, the count value of the electrostatic capacitance detected by the operated touch switch (an example of a sensor value) is used as a reference value.

[0071] The outer edge of the touch switch is the edge that surrounds each touch switch. Near the outer edge of the touch switch, there is a region with an electrostatic capacitance equal to (for example, with a difference of ±10%) that is located inside and outside the outer edge of each touch switch. Thus, a first threshold (1) can be determined to determine the presence or absence of touch operation even when the hand H is wearing gloves, so the region corresponding to the first threshold (1) reaches a position outside the outer edge of each touch switch.

[0072] The electrostatic capacitance detected by each touch switch when the touch switch is touched by the fingertip FT of a gloved hand H is smaller than that detected when the touch switch is touched by a bare hand. This is because the distance between the touch switch and the fingertip FT increases with the thickness of the glove. Therefore, the first threshold (1) is smaller than the threshold that can determine the presence or absence of a touch operation when the touch operation is performed by a bare hand, and the area corresponding to the first threshold (1) is larger than the area corresponding to the threshold that can determine the presence or absence of a touch operation when the touch operation is performed by a bare hand.

[0073] The second threshold (2) in the determination process of the determination unit 123 in the embodiment has a value larger than the first threshold (1) in the same way as the second threshold (2) used for comparison. However, regarding touch switches 114 and 115, the area represented by the dashed line inside the gray area is different from the second threshold (2) used for comparison. That is, in the determination process of the determination unit 123 in the embodiment, the value of the second threshold (2) is set so that an electrostatic capacitance exceeding the second threshold (2) can be obtained in the area represented by the dashed line. The area represented by the dashed line corresponding to the second threshold (2) is the central area of ​​the gray area corresponding to the first threshold (1), excluding the part closer to the outer edge. That is, the second threshold (2) is larger than the first threshold (1).

[0074] Furthermore, the third threshold (3) in the determination process of the determination unit 123 in the embodiment, with respect to touch switches 114 and 115, corresponds to the area indicated by a single-dot-dash line inside the gray area. That is, in the determination process of the determination unit 123 in the embodiment, the value of the third threshold (3) is set in such a way that an electrostatic capacitance exceeding the third threshold (3) can be obtained in the area indicated by the single-dot-dash line.

[0075] The region represented by the dashed line corresponding to the third threshold (3) is contained within the region represented by the dashed line corresponding to the second threshold (2), and is the region on the center side of the region represented by the dashed line. In order to determine that the touch operation was performed more centrally by using the third threshold (3) compared to the determination based on the second threshold (2), the region represented by the dashed line corresponding to the third threshold (3) is located on the center side of the region represented by the dashed line corresponding to the second threshold (2). That is, the third threshold (3) is larger than the second threshold (2).

[0076] The third threshold (3) is a value based on the sensor value detected by the operated touch switch when the hand H or fingertip FT operates the central area of ​​the touch switch. The area corresponding to the third threshold (3) is an example of the central area of ​​touch switches 114 and 115.

[0077] When using the above three thresholds (1), (2), and (3), the second threshold (2) can be set to a value between the first threshold (1) and the third threshold (3). For example, the second threshold (2) can also be set to the midpoint between the first threshold (1) and the third threshold (3), or to the value obtained by multiplying the third threshold (3) by a specified percentage.

[0078] Regarding the first threshold (1) and the third threshold (3), they can be set based on the detection sensitivity of the touch switch, the area of ​​the touch switch, or the distance between the touch switch and the adjacent touch switches. Furthermore, the detection sensitivity is represented by the electrostatic capacitance of the touch switch for a given touch operation; a larger electrostatic capacitance for a given touch operation results in higher detection sensitivity, and a smaller electrostatic capacitance for a given touch operation results in lower detection sensitivity.

[0079] In addition, Figure 7 (A) Figure 7 In (B), the three first thresholds (1), second thresholds (2) and the area corresponding to the third threshold (3) are shown for touch switches 114 and 115, but the same applies to touch switches 111-113 and 116-119.

[0080] In the determination process of the determination unit 123 in the embodiment, the touch switches that have been touched are determined by using at least three thresholds for each of the touch switches 111 to 119. Hereinafter, the determination process of determining the touch switches that have been touched by using three first thresholds (1), second thresholds (2) and third thresholds (3) will be described as an example.

[0081] Figure 8 This diagram illustrates the determination process performed by the determination unit 123 in the embodiment. Figure 8 (A) Figure 8 In (C), simplified touch switches 114 to 116 and electrostatic capacitors obtained from touch switches 114 to 116 are represented.

[0082] exist Figure 8 In (A), the electrostatic capacitance represents the state where the fingertip FT touches the touch switch 114 but is close to the touch switch 115. Such a position of the fingertip FT may occur during the movement of the fingertip FT from the touch switch 114 toward the touch switch 115. The electrostatic capacitance of the touch switch 114 exceeds the third threshold (3), the electrostatic capacitance of the touch switch 115 exceeds the first threshold (1) but is less than the second threshold (2), and the electrostatic capacitance of the touch switch 116 is less than the first threshold (1). In the case where there is only one touch switch with an electrostatic capacitance exceeding the third threshold (3), it is determined that a touch operation has been performed on the touch switch 114 with an electrostatic capacitance exceeding the third threshold (3). The touch switch 114 with an electrostatic capacitance exceeding the third threshold (3) is an example of a touch switch corresponding to an electrostatic capacitance (output) exceeding the third threshold (3), and the fact that there is only one touch switch with an electrostatic capacitance exceeding the third threshold (3) is an example of one output exceeding the third threshold (3). Furthermore, in this case, the electrostatic capacitance of the touch switch 114 is an example of one output, which is determined to be a touch operation performed on the touch switch 114, and is an example of extracting one output.

[0083] In addition, the third threshold (3) can be set to a value that the electrostatic capacitance of the multiple touch switches will not exceed when the fingertip FT touches multiple touch switches across multiple touch switches.

[0084] exist Figure 8In (B), the electrostatic capacitance represents the state of the fingertip FT touching touch switches 114 and 115. This situation may occur as the fingertip FT moves from touch switch 114 toward touch switch 115. The electrostatic capacitance of touch switches 114 and 115 is both below the third threshold (3) and exceeds the second threshold (2). In this case, the touch operation is determined to be performed on touch switch 114, which is determined to have an electrostatic capacitance that exceeds the first threshold (1) in time. In addition, the state where the electrostatic capacitance of touch switches 114 and 115 is both below the third threshold (3) and exceeds the second threshold (2) is an example of a state where there are two outputs below one of the multiple comparison thresholds, and the electrostatic capacitance of touch switches 114 and 115 is an example of two outputs.

[0085] In addition, if the electrostatic capacitance of touch switches 114 and 115 is below the second threshold (2) and exceeds the first threshold (1), it is sufficient to determine that the touch operation is performed on a touch switch whose electrostatic capacitance exceeds the first threshold (1) in time sequence.

[0086] exist Figure 8 (C) represents the electrostatic capacitance of a fingertip FT touching touch switch 115 but catching on touch switch 114. Such a position of fingertip FT may occur during the movement of fingertip FT from touch switch 114 toward touch switch 115. The electrostatic capacitance of touch switch 115 exceeds the third threshold (3), the electrostatic capacitance of touch switch 114 exceeds the second threshold (2) but is below the third threshold (3), and the electrostatic capacitance of touch switch 116 is below the first threshold (1). If there is only one touch switch with an electrostatic capacitance exceeding the third threshold (3), it is determined that a touch operation was performed on touch switch 115 with an electrostatic capacitance exceeding the third threshold (3).

[0087] use Figure 8 (A) Figure 8 The decision processing described in (C) is part of the decision processing of decision unit 123. Decision unit 123 performs the following decision processing.

[0088] If there is only one touch switch with an electrostatic capacitance exceeding the third threshold (3), the determination unit 123 determines that a touch operation has been performed on the touch switch with an electrostatic capacitance exceeding the third threshold (3).

[0089] If there is only one touch switch with an electrostatic capacitance exceeding the second threshold (2), the determination unit 123 determines that a touch operation has been performed on the touch switch with an electrostatic capacitance exceeding the second threshold (2).

[0090] If there is only one touch switch with an electrostatic capacitance exceeding the first threshold (1), the determination unit 123 determines that a touch operation has been performed on the touch switch with an electrostatic capacitance exceeding the first threshold (1).

[0091] In addition, in cases other than those described above, if there are multiple electrostatic capacitances exceeding the first threshold (1) of a touch switch, the determination unit 123 makes the determination as follows.

[0092] If the electrostatic capacitance of all touch switches is less than the third threshold (3) and there are multiple touch switches with electrostatic capacitance exceeding the second threshold (2), the determination unit 123 determines that a touch operation was performed on the touch switch whose electrostatic capacitance first exceeded the second threshold (2) in terms of timing.

[0093] Furthermore, if there are multiple touch switches with electrostatic capacitance less than the second threshold (2) and electrostatic capacitance exceeding the first threshold (1), it is determined that a touch operation was performed on the touch switch whose electrostatic capacitance first exceeded the first threshold (1) in terms of timing.

[0094] Furthermore, if there are multiple touch switches with electrostatic capacitance exceeding the third threshold (3), the determination unit 123 determines that a touch operation was performed on the touch switch whose electrostatic capacitance first exceeded the third threshold (3) in timing. The third threshold (3) is set to a value that the electrostatic capacitance of multiple touch switches will not exceed when the fingertip FT touches multiple touch switches. However, for example, there may be multiple touch switches that are touched by multiple fingers or palms, resulting in multiple touch switches with electrostatic capacitance exceeding the third threshold (3). Therefore, in the case of multiple touch switches with electrostatic capacitance exceeding the third threshold (3), the determination unit 123 only needs to determine that a touch operation was performed on the touch switch whose electrostatic capacitance first exceeded the third threshold (3) in timing.

[0095] Furthermore, if the determination unit 123 determines that no touch operation was performed on any touch switch if there is no touch switch whose electrostatic capacitance exceeds the first threshold (1). In addition, the form of determining that a touch operation was performed on the touch switch whose electrostatic capacitance exceeded a certain threshold first in time is described here, but it is also possible to determine that a touch operation was performed on the touch switch whose electrostatic capacitance exceeded a certain threshold last.

[0096] Figure 9 This is a flowchart illustrating the decision processing performed by the decision unit 123. Figure 9 The flowchart shown illustrates the processing performed by the capacitive input method of the embodiment. The determination unit 123 repeatedly executes the process at a predetermined control cycle during the period when the power supply to the capacitive input device 100 is turned on. Figure 9 The process shown is a series of steps from start to finish. The power supply to the electrostatic capacitive input device 100 is turned on, for example, when the ignition switch of a vehicle equipped with the electrostatic capacitive input device 100 is in acceleration mode or on.

[0097] The determination unit 123 obtains the electrostatic capacitance of all touch switches 111-119 and determines whether there are any touch switches whose electrostatic capacitance exceeds the first threshold (1) (step S1). The determination unit 123 performs step S1 by comparing the electrostatic capacitance of all touch switches 111-119 with the first threshold (1). The process of step S1 is an example of the first comparison, and the result of the process of step S1 is an example of the comparison result of the first comparison.

[0098] In step S1, the determination unit 123 obtains the electrostatic capacitance of all touch switches 111 to 119 from the electrostatic capacitance detection unit 122. The electrostatic capacitance detection unit 122 detects the electrostatic capacitance of touch switches 111 to 119 one by one in a timing sequence.

[0099] If the determination unit 123 determines that there is a touch switch whose electrostatic capacitance exceeds the first threshold (1) (S1: Yes), then it will process the determination of the determination unit 123 for all touch switches 111 to 119. Figure 9 The touch information, representing the final determination result of the previous step in the flowchart, is saved to a designated area in the memory 124 (step S2). Touch information is information that indicates... Figure 9 The flowchart ends by determining which touch switch was touched. In the initial process, since there is no final determination result from the previous process, there is no touch information. If it is determined that no touch operation was performed on any of the touch switches 111-119, the touch information indicates that no touch operation was performed on any of the touch switches 111-119.

[0100] The determination unit 123 saves the electrostatic capacitance of all touch switches 111 to 119 to the memory 124 (step S3).

[0101] For all touch switches 111 to 119, determination unit 123 determines whether the touch switch exceeds the first threshold (1) (on 1), exceeds the second threshold (2) (on 2), exceeds the third threshold (3) (on 3), or is below the first threshold (1) (off) (step S4). The process of determining whether the second threshold (2) is exceeded (on 2) and the process of determining whether the third threshold (3) is exceeded (on 3) are examples of the second comparison, and the result of these processes is an example of the comparison result of the second comparison. Determination unit 123 determines that the state of the touch switch whose electrostatic capacitance exceeds the first threshold (1) and exceeds the second threshold (2) is on 2. Determination unit 123 determines that the state of the touch switch whose electrostatic capacitance exceeds the second threshold (2) and exceeds the third threshold (3) is on 3. Thus, for touch switches whose electrostatic capacitance exceeds the first threshold (1), it is determined whether the touch switch is on 1, on 2, or on 3.

[0102] For the switches determined to be turned on 1, 2, or 3 in step S4, the determination unit 123 compares the information of turning on 1, 2, or 3 with the adjacent touch switches to determine all touch switches that can be determined to have been touched (step S5).

[0103] The determination unit 123 determines whether, among the touch switches that were determined to have been touched in step S5, there is a touch switch that was determined to have been touched based on the touch information and stored in step S2 as the final determination result of the previous step (step S6).

[0104] If the determination unit 123 determines that a touch switch has been touched (S6: Yes), it outputs the touch information stored in step S2 as the final determination result of the previous step as is (step S7). If the determination unit 123 ends the processing in step S7, it ends the series of processes (end).

[0105] Furthermore, if the determination unit 123 determines in step S6 that there is no touch switch that was determined to have been touched in step S2 (S6: No), it outputs touch information indicating that a touch operation was performed on the touch switch with the smallest number in regions (1) to (9) among the touch switches determined in step S5 (step S8). As an example, such as Figure 1 As shown, when the right thumb of the hand holding the spokes of the steering wheel 10 operates the touch switches 111-119, the touch switch 111 is the furthest from the thumb, and the touch switch 119 is the closest, with the touch switches 111-119 being the closest in that order. Therefore, it is assumed that when multiple operations are performed simultaneously, the touch operation of the more distant touch switch is preferentially determined. Furthermore, this determination order is just one example; for instance, it could also be as follows: Figure 8As explained in the text, it is determined that a touch operation was performed on a touch switch whose electrostatic capacitance first exceeded the first threshold (1), the second threshold (2), or the third threshold (3) in terms of timing.

[0106] In addition, if the determination unit 123 determines in step S1 that there is no touch switch whose electrostatic capacitance exceeds the first threshold (1) (S1: No), it outputs touch information indicating that the touch switch has not been touched (step S9).

[0107] Figure 10 This is a flowchart showing the detailed processing of step S4. Figure 10 The process shown includes steps S400 to S409.

[0108] The determination unit 123 sets the determination result of all touch switches 111 to 119 to be off (step S400).

[0109] The determination unit 123 selects one specific touch switch from all touch switches 111 to 119 (step S401). Here, it is sufficient to select only one of touch switches 111 to 119 as the specific touch switch. Since steps S401 to S409 are repeated nine times, selecting each touch switch 111 to 119 one by one as the specific touch switch, as an example, it is sufficient to select touch switches 111 to 119 sequentially. The output of the specific touch switch is an example of a specific output. The output of the touch switch other than the specific touch switch is an example of a non-specific output other than a specific output.

[0110] The determination unit 123 determines whether the electrostatic capacitance of a specific touch switch exceeds the first threshold (1) (step S402).

[0111] If the determination unit 123 determines that the electrostatic capacitance of a specific touch switch exceeds the first threshold (1) (S402: Yes), it determines whether the electrostatic capacitance of the specific touch switch exceeds the second threshold (2) (step S403).

[0112] If the determination unit 123 determines that the electrostatic capacitance of a specific touch switch exceeds the second threshold (2) (S403: Yes), it then determines whether the electrostatic capacitance of the specific touch switch exceeds the third threshold (3) (step S404). The determination unit 123 determines whether the electrostatic capacitance of the specific touch switch exceeds a certain comparison threshold by performing the processing steps S402 to S404.

[0113] If the determination unit 123 determines that the electrostatic capacitance of a specific touch switch exceeds the third threshold (3) (S404: Yes), it sets the determination result of the specific touch switch to be turned on 3 (step S405).

[0114] The determination unit 123 determines whether all touch switches 111 to 119 have been selected as a specific touch switch (step S406).

[0115] If the determination unit 123 determines that not all touch switches 111-119 have been selected as a specific touch switch (S406: No), the process returns to step S401. This is to repeatedly execute the process from step S401 to step S409 in order to select a new specific touch switch.

[0116] Furthermore, if the determination unit 123 determines in step S402 that the electrostatic capacitance of a specific touch switch does not exceed the first threshold (1) (S402: No), then the determination result of the specific touch switch is set to off (step S407).

[0117] Furthermore, if the determination unit 123 determines that the electrostatic capacitance of a specific touch switch does not exceed the second threshold (2) (S403: No), then the determination result of the specific touch switch is set to ON 1 (step S408).

[0118] Furthermore, if the determination unit 123 determines that the electrostatic capacitance of a specific touch switch does not exceed the third threshold (3) (S404: No), then the determination result of the specific touch switch is set to ON 2 (step S409).

[0119] Figure 11 This is a flowchart showing the detailed processing of step S5. Figure 11 The process shown includes steps S500 to S509.

[0120] For switches determined to be ON 1, ON 2, or ON 3 in step S4, the determination unit 123 initializes the output arrangement to OFF (step S500). The output arrangement is stored in a region of memory 124, which is different from the region storing the determination results of ON 1, ON 2, ON 3, and OFF in step S4, and is stored in a designated region that stores the determination results of step S5.

[0121] The determination unit 123 selects one of the touch switches that was not determined to be off in step S4 as a specific touch switch (step S501).

[0122] The determination unit 123 determines whether a specific touch switch is set to ON 1 (step S502).

[0123] If the determination unit 123 determines that a specific touch switch is set to ON 1 (S502: Yes), it determines whether the adjacent touch switch of the specific touch switch is set to ON 2 or ON 3 (step S503).

[0124] If the determination unit 123 determines that the touch switch adjacent to the specific touch switch is set to ON 2 or ON 3 (S503: Yes), then the state of the specific touch switch is set to OFF and added to the output arrangement (step S504).

[0125] The determination unit 123 determines whether all touch switches that were not set to off in step S4 have been selected (step S505). If the determination unit 123 determines that all have been selected (S505: Yes), the process proceeds to step S6.

[0126] Furthermore, if the determination unit 123 determines in step S502 that a specific touch switch is not set to ON 1 (S502: No), then it determines whether the specific touch switch is set to ON 2 (step S506).

[0127] If the determination unit 123 determines that a specific touch switch is set to ON 2 (S506: Yes), it determines whether the touch switch adjacent to the specific touch switch is set to ON 3 (step S507).

[0128] If the determination unit 123 determines that the touch switch adjacent to the specific touch switch is set to ON 3 (S507: Yes), then the state of the specific touch switch is set to OFF and added to the output arrangement (step S508).

[0129] Furthermore, if the determination unit 123 determines in step S506 that a specific touch switch is not set to ON 2 (S506: No), or if it determines in step S507 that a touch switch adjacent to the specific touch switch is not set to ON 3 (S507: No), the state of the specific touch switch is set to ON and added to the output arrangement (step S509).

[0130] Based on the above, the touch switches that have been touched are identified among touch switches 111 to 119.

[0131] Figure 12 This is a graph showing the relationship between the distribution of electrostatic capacitance and the first threshold (1), the second threshold (2), and the third threshold (3). Figure 12 In the middle, it indicates that the... Figure 3 The white bar diagram of the electrostatic capacitance of the touch switch 114 shown in (A) when a touch operation is performed indicates the presence of a capacitive electrode. Figure 3 The black bar graph of electrostatic capacitance of the touch switch 115 when a touch operation is performed, as shown in (B), and the first threshold (1), the second threshold (2) and the third threshold (3). Figure 12 The white bar chart and the black bar chart shown are... Figure 4The white bar chart shown in (B) is the same as the black bar chart.

[0132] like Figure 12 As shown, in the 5th to 9th columns of the central portion corresponding to the horizontal direction of touch switch 114, electrostatic capacitance exceeding the third threshold (3) is obtained, and in the 12th to 15th columns of the central portion corresponding to the horizontal direction of touch switch 115, electrostatic capacitance exceeding the third threshold (3) is obtained. Furthermore, regarding the 10th and 11th rows corresponding to the boundary between touch switch 114 and touch switch 115, in the 10th row, the electrostatic capacitance of touch switch 114 exceeds the second threshold (2), while the electrostatic capacitance of touch switch 115 is below the second threshold (2); in the 11th row, the electrostatic capacitance of touch switch 114 is below the second threshold (2), while the electrostatic capacitance of touch switch 115 exceeds the second threshold (2).

[0133] Therefore, an electrostatic capacitive input device 100 is provided that can determine which of a plurality of touch switches has been touched. By setting thresholds in multiple stages, the electrostatic capacitive input device 100 can compare the quality of detection sensitivity (electrostatic sensitivity) over a fine area, and as a result, can smoothly determine the presence of a finger swipe.

[0134] Furthermore, the above example of multiple comparison thresholds is the second threshold (2) and the third threshold (3). The determination unit 123 uses the thresholds of the first threshold (1), the second threshold (2), and the third threshold (3) to determine which of the touch switches 111 to 119 has been touched. However, the number of multiple comparison thresholds can also be three or more. That is, the determination unit 123 can also use four or more thresholds to determine which of the touch switches 111 to 119 has been touched.

[0135] Furthermore, the above description describes the configuration of the operation unit 110 having nine touch switches 111 to 119. However, the operation unit 110 only needs to have multiple touch switches, and the number of touch switches can be two or more.

[0136] Furthermore, the above description of the first threshold (1) as a low value that can be used to determine the presence or absence of a touch operation even when gloves are worn on the hand H is explained. However, the first threshold (1) is only required to be a value that can detect the presence or absence of a touch operation when the electrostatic capacitance of the touch switch is smaller than that of a touch operation performed with bare hands. It is not limited to a low value that can be used to determine the presence or absence of a touch operation even when gloves are worn on the hand H.

[0137] The above describes an exemplary embodiment of the electrostatic capacitive input device and electrostatic capacitive input method of the present invention. However, the present invention is not limited to the specific embodiments disclosed, and various modifications or alterations can be made without departing from the claims.

[0138] Label Explanation

[0139] 10. Steering wheel

[0140] 100 Electrostatic Capacitive Input Device

[0141] 110 Operations Department

[0142] 111-119 Touch switches

[0143] 120 control device

[0144] 121 Main Control Unit

[0145] 122 Electrostatic Capacitance Testing Department

[0146] 123 Judgment Department

[0147] 124 memory

Claims

1. An electrostatic capacitive input device, wherein, include: Multiple touch switches; as well as The determination unit, based on the outputs of the plurality of touch switches, determines a touch operation on one of the plurality of touch switches. The above-mentioned determination unit performs the following operations: The first comparison is performed by comparing the first threshold used in determining the presence or absence of the touch operation with the outputs of the plurality of touch switches respectively. A second comparison is performed, which compares the output of the plurality of touch switches that is greater than the first threshold with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. as well as Based on the comparison result obtained in the first comparison or the second comparison above, a touch operation on one of the plurality of touch switches is determined. If the result of the second comparison is one of the outputs exceeding one of the plurality of comparison thresholds, the determination unit determines that the touch operation was performed on the touch switch corresponding to that one output among the plurality of touch switches. In the second comparison described above, if multiple outputs from the aforementioned multiple touch switches are larger than the first threshold, then... The aforementioned determination unit extracts one output that exceeds a certain comparison threshold by performing the following operation on multiple outputs: Select one of the above outputs as a specific output, and Determine whether the selected specific output exceeds one of the multiple comparison thresholds, and whether the non-specific outputs other than the selected specific output among the multiple outputs do not exceed the multiple comparison thresholds.

2. The electrostatic capacitive input device as described in claim 1, wherein, If the result of the second comparison is that there are two outputs below one of the multiple comparison thresholds and both of these outputs are within the range between two adjacent comparison thresholds of the same multiple comparison thresholds, or within the range between the lowest comparison threshold and the first threshold, the determination unit determines that the touch operation was performed on the touch switch corresponding to the earlier output or the later output among the multiple touch switches.

3. The electrostatic capacitive input device as described in claim 2, wherein, In the second comparison described above, if multiple outputs from the aforementioned multiple touch switches are larger than the first threshold, then... The aforementioned determination unit extracts the two outputs below a certain comparison threshold by performing the following operation on multiple of the aforementioned outputs: Select one of the above outputs as a specific output, and Determine whether the selected specific output is below a certain comparison threshold, and whether any non-specific output other than the selected specific output among the multiple outputs is below the certain comparison threshold.

4. The electrostatic capacitive input device as described in claim 1, wherein, The aforementioned non-specific output is the output of the touch switch adjacent to the touch switch that has received the aforementioned specific output, which is one of the selected outputs other than the aforementioned specific output among the aforementioned multiple outputs.

5. The electrostatic capacitive input device as described in claim 1, wherein, The largest comparison threshold among the above multiple comparison thresholds and the first threshold are set based on the detection sensitivity of the touch switch, the area of ​​the touch switch, or the distance between the touch switch and the touch switch adjacent to it.

6. The electrostatic capacitive input device as described in claim 1, wherein, The largest of the aforementioned comparison thresholds is a value based on the sensor value detected by the touch switch when the operator operates the central area of ​​the touch switch.

7. The electrostatic capacitive input device as claimed in claim 1, wherein, The aforementioned first threshold is a value based on the sensor value detected by the touch switch when the operator operates on or near the outer edge of the touch switch.

8. The electrostatic capacitive input device according to any one of claims 1 to 7, wherein, The aforementioned multiple touch switches are switches located on the vehicle's steering mechanism.

9. A capacitive input device, wherein, include: Multiple touch switches; as well as The determination unit, based on the outputs of the plurality of touch switches, determines a touch operation on one of the plurality of touch switches. The above-mentioned determination unit performs the following operations: The first comparison is performed by comparing the first threshold used in determining the presence or absence of the touch operation with the outputs of the plurality of touch switches respectively. A second comparison is performed, which compares the output of the plurality of touch switches that is greater than the first threshold with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. as well as Based on the comparison result obtained in the first comparison or the second comparison above, a touch operation on one of the plurality of touch switches is determined. If the result of the second comparison is that there are two outputs below one of the multiple comparison thresholds and both of these outputs are within the range between two adjacent comparison thresholds of the same multiple comparison thresholds, or within the range between the lowest comparison threshold and the first threshold, the determination unit determines that the touch operation was performed on the touch switch corresponding to the earlier output or the later output among the multiple touch switches.

10. The electrostatic capacitive input device as claimed in claim 9, wherein, In the second comparison described above, if multiple outputs from the aforementioned multiple touch switches are larger than the first threshold, then... The aforementioned determination unit extracts the two outputs below a certain comparison threshold by performing the following operation on multiple of the aforementioned outputs: Select one of the above outputs as a specific output, and Determine whether the selected specific output is below a certain comparison threshold, and whether any non-specific output other than the selected specific output among the multiple outputs is below the certain comparison threshold.

11. The electrostatic capacitive input device as claimed in claim 9, wherein, The aforementioned first threshold is a value based on the sensor value detected by the touch switch when the operator operates on or near the outer edge of the touch switch.

12. The electrostatic capacitive input device according to any one of claims 9 to 11, wherein, The aforementioned multiple touch switches are switches located on the vehicle's steering mechanism.

13. A capacitive input method, in a capacitive input device including a plurality of touch switches and a determination unit that determines a touch operation to one of the plurality of touch switches based on the output of the plurality of touch switches, The above-mentioned determination unit performs the following operations: The first comparison is performed by comparing the first threshold used in determining the presence or absence of the touch operation with the outputs of the plurality of touch switches respectively. A second comparison is performed, which compares the outputs of the plurality of touch switches that are greater than the first threshold with a plurality of comparison thresholds that are greater than the first threshold and are different from each other; and Based on the comparison result obtained in the first comparison or the second comparison above, a touch operation on one of the plurality of touch switches is determined. If the result of the second comparison is one of the outputs exceeding one of the plurality of comparison thresholds, the determination unit determines that the touch operation was performed on the touch switch corresponding to that one output among the plurality of touch switches. In the second comparison described above, if multiple outputs from the aforementioned multiple touch switches are larger than the first threshold, then... The aforementioned determination unit extracts one output that exceeds a certain comparison threshold by performing the following operation on multiple outputs: Select one of the above outputs as a specific output, and Determine whether the selected specific output exceeds one of the multiple comparison thresholds, and whether the non-specific outputs other than the selected specific output among the multiple outputs do not exceed the multiple comparison thresholds.

14. A capacitive input method, in a capacitive input device including a plurality of touch switches and a determination unit that determines a touch operation to one of the plurality of touch switches based on the output of the plurality of touch switches, The above-mentioned determination unit performs the following operations: The first comparison is performed by comparing the first threshold used in determining the presence or absence of the touch operation with the outputs of the plurality of touch switches respectively. A second comparison is performed, which compares the outputs of the plurality of touch switches that are greater than the first threshold with a plurality of comparison thresholds that are greater than the first threshold and are different from each other; and Based on the comparison result obtained in the first comparison or the second comparison above, a touch operation on one of the plurality of touch switches is determined. If the result of the second comparison is that there are two outputs below one of the multiple comparison thresholds and both of these outputs are within the range between two adjacent comparison thresholds of the same multiple comparison thresholds, or within the range between the lowest comparison threshold and the first threshold, the determination unit determines that the touch operation was performed on the touch switch corresponding to the earlier output or the later output among the multiple touch switches.

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