JP2021170751A - Touch detection device - Google Patents

Abstract

To suppress decrease in detection accuracy of a touch operation.SOLUTION: A controller of a touch detection device updates a base capacity value Cbase that is the basis of a threshold Cth to detect a touch operation from a capacitance value Cap, when a long press operation for a duration Ts or longer is performed on a touch operation part. In the update of the base capacity value Cbase, a capacitance value Cap before decrease is set to an initial value C0 and a capacitance value ΔC is set depending on whether the capacitance value Cap is equal to or greater than a specified capacity value Cref (steps 120-128); and then, a capacitance value Cap after the change of a capacitance value Cap from the initial value C0 has reached the capacitance value ΔC is set to the base capacity value Cbase (steps 132-140). Thus, the base capacity value Cbase with respect to the threshold Cth can be appropriately undated, so that decrease in detection accuracy of a touch operation can be suppressed.SELECTED DRAWING: Figure 4

Description

The present invention relates to a touch detection device.

The touch-type input device of Patent Document 1 is a touch panel in which a plurality of drive electrodes and a plurality of sensor electrodes are stacked in a grid pattern to form a sensor pattern, and the electrostatic capacitance at each intersection of the drive electrodes and the sensor electrodes. The controller detects the change in and detects the touch operation. In this touch-type input device, the reference value is updated when each of the capacitances at the intersections is within a certain range for a certain period of time.

JP-A-2017-111507

By the way, in the touch sensor, when the reference value is updated by keeping the state within a certain range of capacitance for a certain period of time, not only the update cycle of the reference value becomes longer but also the reference value is updated. Timing is limited. From this, a method of updating the reference value by using the capacitance after a lapse of a predetermined time after a long press operation of touching the touch sensor for a long time can be considered.

However, in this method, the time for updating the reference value can be shortened by shortening the elapsed time after the long press operation, but the reference value is set in a state where the capacitance is not sufficiently reduced. If set, it will cause false detection.

The present invention has been made in view of the above facts, and an object of the present invention is to provide a touch detection device capable of suppressing a decrease in detection accuracy.

The touch detection device of the first aspect for achieving the above object has a sensor unit in which the capacitance in the sensor electrode changes when the operator is brought close to the sensor electrode, and a capacitance value in the sensor electrode. Using the detection unit to be detected, the preset reference value, and the threshold value set for the reference value, the capacitance value detected by the detection unit has reached the threshold value. A determination unit that determines whether or not the operator is close to the sensor unit, and a predetermined elapsed time in a state where the capacitance value detected by the detection unit reaches the threshold value. When the elapsed capacitance value is equal to or higher than the preset specified value, the capacitance value is set as the initial value, and the initial value of the capacitance value detected by the detection unit is set. Includes an update unit that updates the capacitance value after reaching a preset change capacitance value as a new reference value.

In the first aspect of the touch detection device of the second aspect, when the capacitance value after the elapsed time has elapsed is less than the specified value, the updating unit has the capacitance value as specified. After the change capacitance value is set so as to be smaller than the case where the value is equal to or more than the value, and the change of the capacitance value detected by the detection unit with respect to the initial value reaches the change capacitance value. Includes updating the capacitance value of.

In the second aspect, the touch detection device of the third aspect has a first capacitance as the changed capacitance value when the capacitance value after the elapsed time elapses is equal to or more than the specified value. The value and the second capacitance value as the change capacitance value when the capacitance value after the elapsed time elapses is less than the specified value are set in advance.

In the touch detection device of the fourth aspect, in any one of the first to third aspects, the updating unit starts to decrease the capacitance value detected by the detecting unit from the time when the elapsed time elapses. The maximum value of the capacitance value until the above is used as the initial value.

In the touch detection device of the fifth aspect, in any one of the first to fourth aspects, the changed capacitance value is a capacitance larger than the difference between the reference value before the update and the threshold value. Let it be a value.

In the touch detection device of the first aspect, a sensor electrode whose capacitance changes when an operator is approached is provided in the sensor unit, and the detection unit detects the capacitance value in the sensor electrode. The determination unit uses a preset reference value and a threshold value set for the reference value, and operates based on whether or not the capacitance value detected by the detection unit has reached the threshold value. It is determined whether or not a person is close to the sensor unit. Therefore, the threshold value is changed by updating the reference value.

The update unit can update the reference value when a predetermined elapsed time elapses in a state where the capacitance value detected by the detection unit reaches the threshold value. In addition, when the capacitance value when a predetermined elapsed time elapses is equal to or higher than a preset specified value, the update unit sets the capacitance value as an initial value and detects it by the detection unit. The change with respect to the initial value of the capacitance value to be performed is updated as a new reference value after reaching the preset change capacitance value.

As a result, since the reference value can be set by securing the change capacitance value with respect to the specified value, it is possible to suppress an erroneous determination caused by the reference value becoming too high, and it is possible to suppress a decrease in detection accuracy.

In the touch detection device of the second aspect, when the capacitance value after the elapsed time elapses is less than the specified value, the static electricity changes so as to be smaller than when the capacitance value is equal to or more than the specified value. Set the capacitance value. Further, the updating unit updates the capacitance value after the change of the capacitance value detected by the detection unit with respect to the initial value reaches the changed capacitance value as a new reference value.

Therefore, it is possible to suppress the reference value from becoming too low, and it is possible to effectively suppress the deterioration of the detection accuracy.

In the touch detection device of the third aspect, the first capacitance value applied as the changing capacitance value when the capacitance value after the elapsed time elapses is equal to or more than the specified value, and the elapsed time have elapsed. The second capacitance value applied as the changing capacitance value when the later capacitance value is less than the specified value is set in advance. Therefore, the reference value for suppressing the decrease in detection accuracy can be appropriately updated.

In the touch detection device of the fourth aspect, the maximum value of the capacitance value from the time when the elapsed time has elapsed until the capacitance value detected by the detection unit starts to decrease is set as the initial value. As a result, even if the way the operator touches the sensor unit changes, the reference value can be updated to an appropriate value.

In the touch detection device of the fifth aspect, the changing capacitance value is set to a capacitance value larger than the difference between the reference value before updating and the threshold value. As a result, the reference value can be set so that the capacitance value exceeds the threshold value when the operator approaches the sensor unit, and it is possible to prevent an erroneous judgment from occurring when the operator approaches the sensor unit. Therefore, the decrease in detection accuracy can be suppressed more effectively.

It is a schematic block diagram which shows the touch detection apparatus which concerns on this embodiment. It is a perspective view which shows the main part of the vehicle in which a touch detection device is arranged. It is a flow chart which shows the outline of the touch detection process. It is a flow chart which shows the outline of the update process. (A) and (B) are diagrams showing a touch operation, a change in capacitance according to the touch operation, and a change in a determination signal, respectively. (A) and (B) are diagram showing the touch operation at the time of long press, the change of the capacitance according to the touch operation, and the change of the judgment signal, and (A) is more than (B). The case where the capacitance value is low is shown.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a schematic configuration diagram of the touch detection device 10 according to the present embodiment.
As shown in FIG. 1, the touch detection device 10 includes a touch operation unit 12 as a sensor unit and a controller 14. The touch operation unit 12 includes a sensor electrode 16, and the sensor electrode 16 is formed in a sheet shape by using a conductive material.

In the touch operation unit 12, the operator (for example, the fingertip of the operator) is brought close to the sensor electrode 16 (touch operation is performed by the touch operation unit 12), so that the capacitance between the sensor electrode 16 and the operator is large. Causes the change in capacitance (capacitance value) Cap at the sensor electrode 16. As such a touch operation unit 12, either a self-capacitance method or a mutual capacity method may be applied, and in the present embodiment, the capacitance between the sensor electrode 16 and a drive electrode (not shown) or the like by touch operation is applied. The mutual capacitance method that changes is applied. In the following description, in order to simplify the description, it is assumed that the capacitance value Cap of the sensor electrode 16 is increased (increased) by the touch operation.

The touch operation unit 12 is electrically connected to the controller 14. The controller 14 detects the capacitance (including parasitic capacitance) and the change in capacitance in the sensor electrode 16 of the touch operation unit 12. The controller 14 determines whether or not the operator's finger is brought close to the sensor electrode 16 due to the change in the capacitance value Cap, that is, whether or not the operator has performed a touch operation on the touch operation unit 12 (sensor electrode 16). judge. When the controller 14 determines that the touch operation has been performed on the sensor electrode 16, the controller 14 turns on the touch signal. Further, the controller 14 is in a non-touch state in which the operator's finger is separated from the sensor electrode 16, so that the non-touch determination is made and the touch signal is turned off.

The touch detection device 10 according to the present embodiment can be connected to various devices to be operated provided in the vehicle 18. FIG. 2 is a perspective view of the main part of the vehicle 18 provided with the touch detection device 10 as viewed from the outside in the vehicle width direction and diagonally from the front side.

As shown in FIG. 2, the vehicle 18 is provided with a door outer handle (hereinafter referred to as a door handle) 22 on the side door 20. The door handle 22 is formed of an insulating material, and any of a grip type, a flap type, and a pop-up type may be applied to the door handle 22 (in FIG. 2, the flap type is used).

The side door 20 is provided with a lock mechanism (not shown), and the lock mechanism is mechanically or electrically connected to the door handle 22. The lock mechanism restricts the opening and closing of the side door 20 when it is in the locked state, and enables the side door 20 to be opened and closed by operating the door handle 22 when it is in the unlocked state.

A touch operation unit 12 (sensor electrode 16) of the touch detection device 10 is arranged on the door handle 22 of the side door 20 on the front seat side. The touch operation unit 12 is arranged on the vehicle outer surface of the door handle 22 with the sensor electrode 16 covered with an insulating material. The touch operation unit 12 is not limited to the side door 20 on the front seat side, and may be arranged on the trunk lid or the steering wheel of the rear gate at the rear of the vehicle. Further, the touch operation unit 12 may be provided on the side door on the rear seat side, and the side door on the rear seat side on which the touch operation unit 12 is arranged may be a slide type as well as a hinge type.

Further, as shown in FIG. 1, a door lock device 24 as an operated device is arranged in the vehicle 18. The door lock device 24 is electrically connected to a door lock mechanism such as the side door 20 (not shown), and the door lock device 24 switches between a locked state and an unlocked state with respect to the lock mechanism.

A door lock device 24 is electrically connected to the controller 14 of the touch detection device 10. The controller 14 outputs a touch signal to the door lock device 24 when the occupant touch-operates the touch operation unit 12 of the door handle 22 of the side door 20. The door lock device 24 switches the lock mechanism between the locked state and the unlocked state each time the touch signal input from the controller 14 is turned on. In the door lock device 24, unlocking according to the touch signal of the controller 14 is restricted by the lock operation from the vehicle interior (control system of the vehicle 18 or the like).

Here, as shown in FIG. 1, the controller 14 of the touch detection device 10 is formed with a detection unit 26, a memory 28 as a storage means, a determination unit 30, and an update unit 32. The controller 14 includes a microcomputer (not shown) to which a CPU, a ROM, a RAM, a storage which is a non-volatile memory, and the like are connected by a bus. In the controller 14, each function of the detection unit 26, the determination unit 30, and the update unit 32 is realized by the CPU reading the program stored in the ROM and the storage and executing the program while expanding the program in the RAM. Further, in the controller 14, the memory 28 is realized by the storage.

The detection unit 26 detects the capacitance (capacitance value Cap) generated in the sensor electrode 16 of the touch operation unit 12 and also detects a change in the capacitance value Cap.

The memory 28 stores various data (capacitance value, time, etc.) preset for making a touch determination using the capacitance value Cap. The memory 28 has a reference capacitance value Cbase as a reference value (reference value capacitance value) and a threshold capacitance value (hereinafter, threshold value Cth) with respect to the reference value (reference capacitance value Cbase). ) Is stored in the difference capacitance value ΔCd for setting. The threshold value Cth with respect to the reference capacitance value Cbase is obtained as Cth = Cbase + ΔCd.

The determination unit 30 uses the data stored in the memory 28 to execute a touch determination as to whether or not the touch operation unit 12 has been touched from the capacitance value Cap, and a determination signal (touch signal) according to the determination result. Is output. When the capacitance value Cap becomes equal to or greater than the threshold value Cth (= reference capacitance value Cbase + capacitance value ΔCd) (Cap ≧ Cth), the determination unit 30 determines that the touch operation has been performed (touch signal is on). Further, the determination unit 30 determines that the non-touch state (touch signal is off) when the capacitance value Cap is lower than the threshold value Cth (Cap <Cth).

Further, in the touch detection device 10, the reference capacitance value Cbase is updated by performing a continuous touch operation (long press operation) on the touch operation unit 12 for a predetermined duration Ts or more. The update unit 32 operates when the touch operation unit 12 (sensor electrode 16) is continuously touched for a duration Ts or longer, and updates the reference capacitance value Cbase stored in the memory 28. In the touch detection device 10, when the reference capacity value Cbase is updated, the threshold value Cth set for the reference capacity value Cbase is updated.

Next, as the operation of the present embodiment, the touch detection process in the touch detection device 10 and the update process of the reference capacitance value Cbase applied to the touch detection process will be described. FIG. 3 shows a flow chart of the touch detection process executed by the controller 14 in the touch detection device 10, and FIG. 4 shows a flow chart of the update process of the reference capacitance value Cbase.

The flowchart of FIG. 3 is executed by the controller 14 by supplying electric power from a power source (battery) (not shown) of the vehicle 18, and the initial setting is performed in the first step 100.

In the touch detection device 10, the reference capacitance value Cbase and the capacitance value ΔCd, as well as the specified capacitance value Cref as the specified value, the changed capacitance value Cdif1 as the changed capacitance value and the second capacitance value, and the static electricity change. The capacitance value and the change capacitance value Cdif2 as the first capacitance value are preset and stored in the memory 28. The specified capacitance value Cref is a value (capacitance value) larger than the threshold value Cth (= reference capacitance value Cbase + capacitance value ΔCd), and the occupant's finger is in a state where noise or the like is not included. The maximum value of the capacitance value Cap generated when the touch operation unit 12 is touched is applied. When a parasitic capacitance or the like occurs in the sensor electrode 16, the capacitance value Cap may exceed the specified capacitance value Cref.

The reference capacitance value Cbase, the capacitance value ΔCd, the specified capacitance value Cref, and the variable capacitance values Cdif1 and Cdif2 are set when the touch detection device 10 is manufactured or when the touch detection device 10 is mounted on the vehicle 18. The changing capacitance values Cdif1 and Cdif2 are set based on each of the reference capacitance value Cbase, the capacitance value ΔCd, and the specified capacitance value Cref, and the difference between the respective capacitance values.

Further, the changing capacitance value Cdif1 and the changing capacitance value Cdif2 are each larger than the capacitance value ΔCd. Further, the change capacity value Cdif2 is set to be a value larger than the change capacity value Cdif1 (Cdif2> Cdif1> ΔCd).

Such changing capacitance values Cdif1 and Cdif2 are the capacitance values (magnitude) of each of the reference capacitance value Cbase, the threshold value Cth, and the specified capacitance value Cref, the ratio of the capacitance values (relative ratio), and the like. Can be set based on. Further, the changing capacitance value Cdif1 and the changing capacitance value Cdif2 can be set as a ratio of the capacitance value such as 1: 2.

As a result, as shown in FIG. 5A, the controller 14 sets the reference capacity value Cbase, the threshold value Cth, and the specified capacity value Cref by initial setting.

As the initial value of the specified capacitance value Cref, the value set at the time of manufacturing the touch detection device 10 or when it is mounted on the vehicle 18 is stored in the memory 28. Further, the specified capacity value Cref stored in the memory 28 is updated at a predetermined timing. In the initial setting of step 100, the value stored in the memory 28 is used as the specified capacity value Cref. Further, in FIGS. 5 (A), 5 (B), 6 (A), and 6 (B), the horizontal axis is the time axis, and FIGS. 5 (A), 5 (B), and 6 (B). A) and FIG. 6 (B) show the time change of the touch operation.

As shown in FIG. 3, the controller 14 starts the touch detection process (touch determination process) when the initial setting is performed. In the touch detection process, the controller 14 executes the steps 102 in order at predetermined time intervals, and in step 102, the capacitance value Cap of the sensor electrode 16 is detected. Further, the controller 14 determines in step 104 whether or not the detected capacitance value Cap is equal to or greater than the threshold value Cth.

When the finger of the occupant as the operator does not touch the touch operation unit 12 and the capacitance value Cap does not reach the threshold value Cth (Cth <Cap), the controller 14 makes a negative determination in step 104 ( Step 104: N), after the transition to step 106, the process returns to step 102. The controller 14 turns off the touch signal in step 106. As a result, as shown in FIG. 5A, while the occupant is not touching the touch operation unit 12, the non-touch state is determined and the off state of the touch signal is continued.

On the other hand, when the occupant performs a touch operation on the touch operation unit 12, the capacitance value Cap increases, and when the capacitance value Cap reaches the threshold value Cth (Cap ≧ Cth), the controller 14 Determines affirmatively in step 104 (step 104: Y), and proceeds to step 108. In step 108, the touch signal is turned ON.

After that, the controller 14 confirms whether or not the duration Ts has been reached for the time when the capacitance value Cap exceeds the threshold value Cth in step 110, that is, the time determined to be in the touch state. If the capacitance value Cap decreases away from the touch operation unit 12 before the occupant's finger reaches the duration Ts and the capacitance value Cap does not reach the threshold value Cth, the controller 14 negates in step 104. The determination is made, and the process proceeds to step 106. As a result, the touch signal output from the controller 14 is turned off.

In the touch detection device 10, a touch operation unit 12 is provided on the door handle 22, and the controller 14 outputs a touch signal to the door lock device 24 in response to a touch operation on the touch operation unit 12. At this time, if the touch operation unit 12 of the door handle 22 is not touched, the controller 14 turns off the touch signal output to the door lock device 24. As a result, when the touch signal is turned off, the door lock device 24 maintains the lock mechanism in the locked or unlocked state, restricts the opening and closing of the side door 20, or can open and close the side door 20. Keep in.

Further, when the touch operation unit 12 of the door handle 22 is touched, the controller 14 turns on the touch signal output to the door lock device 24. As a result, when the lock mechanism is in the locked state, the door lock device 24 switches the lock mechanism to the unlocked state so that the side door 20 can be opened and closed. Further, when the lock mechanism is in the unlocked state, the door lock device 24 switches the lock mechanism to the locked state to limit the opening and closing of the side door 20.

On the other hand, in the touch detection device 10, if the door handle 22 on which the touch operation unit 12 is arranged becomes dirty or the parasitic capacitance of the sensor electrode 16 of the touch operation unit 12 increases, the touch detection device 10 is in a non-touch state. Even if there is, the capacitance value Cap changes such as the capacitance value Cap increases. In this case, the touch detection device 10 is likely to cause an erroneous determination for the touch operation. In particular, as shown in FIG. 5 (B), when the reference capacitance value Cbase becomes too high and the threshold value Cth becomes too high, the controller 14 has a capacitance even though a touch operation is performed. The value Cap cannot exceed the threshold value Cth, and it is erroneously determined as a non-touch state.

The controller 14 of the touch detection device 10 turns on the touch signal when the touch operation unit 12 is touched. Further, the touch operation unit 12 is continuously pressed and held (see FIGS. 6A and 6B), and the time during which the touch operation is detected reaches the duration Ts. As a result, the controller 14 makes an affirmative determination (step 110: Y) in step 110 and updates the reference capacitance value Cbase (step 112).

Here, the update process of the reference capacitance value Cbase in the controller 14 of the touch detection device 10 will be described with reference to FIGS. 4, 6 (A) and 6 (B). Note that FIG. 6A shows a case where the capacitance value Cap after the elapse of the duration Ts is equal to or greater than the specified capacitance value Cref, and FIG. 6B shows the static electricity after the elapse of the duration Ts. The case where the capacitance value Cap is less than the specified capacitance value Cref is shown.

As shown in FIGS. 6A and 6B, when the occupant stops pressing and holding the touch operation unit 12 (door handle 22) after the long press operation and the occupant's finger separates from the sensor electrode 16. , The capacitance value Cap detected by the detection unit 26 decreases.

By executing the update process of the reference capacitance value Cbase of FIG. 4, the controller 14 detects the capacitance value Cap in the first step 120. Further, the controller 14 determines whether or not the reduction of the capacitance value Cap has started in step 122. When the occupant stops pressing and holding the touch operation unit 12 (door handle 22) and the capacitance value Cap detected by the detection unit 26 decreases, the controller 14 makes an affirmative determination in step 122 (step 122: Y). , Step 124.

In step 124, the controller 14 sets the capacitance value Cap immediately before the decrease to the initial value C0. That is, the controller 14 sets the capacitance value Cap immediately before the decrease to the initial value C0 of the capacitance value at the time of updating.

When the touch operation unit 12 is pressed and held for a long time, if the force (contact area) that touches the touch operation unit 12 changes, the capacitance value Cap also changes. From here, the controller 14 may apply the maximum value of the capacitance value Cap after the duration Ts has elapsed as the initial value C0.

Further, the controller 14 temporarily sets the capacitance value Cap (initial value C0) immediately before the decrease to the reference capacitance value Cbase. As a result, the threshold value Cth can be increased, and the controller 14 is restricted from turning on the touch signal when the reference capacitance value Cbase is updated.

In the next step 126, the controller 14 compares the initial value C0 with the specified capacity value Cref, and confirms whether or not the initial value C0 is equal to or greater than the specified capacity value Cref. If the initial value C0 does not reach the specified capacitance value Cref (Cth ≦ C0 <Cref, see FIG. 6B), the controller 14 makes a negative determination (step 126: N) in step 126 and proceeds to step 128. .. The controller 14 sets the capacitance value ΔC indicating the amount of change to the change capacitance value Cdif1 in step 128.

Further, when the initial value C0 is equal to or higher than the specified capacitance value Cref (C0 ≧ Cref> Cth, see FIG. 6A), the controller 14 makes an affirmative determination (step 126: Y) in step 126 and steps 130. Move to. The controller 14 sets the capacitance value ΔC to the changing capacitance value Cdif2 in step 130.

When the controller 14 sets the capacitance value ΔC to the changing capacitance value Cdif1 or the changing capacitance value Cdif2 based on the initial value C0 and the specified capacitance value Cref, the controller 14 proceeds to step 132 and detects the capacitance value Cap. Further, in the controller 14, whether or not the capacitance value Cap is reduced by the capacitance value ΔC from the initial value C0 in step 134, that is, the change in the decreasing capacitance value Cap reaches the capacitance value ΔC. Check if you did.

When the capacitance value Cap decreases by the capacitance value ΔC from the initial value C0 (Cap ≦ (C0−ΔC)), the controller 14 makes an affirmative determination in step 134 (step 134: Y), and proceeds to step 136. do. When the decrease in the capacitance value Cap from the initial value C0 does not reach the capacitance value ΔC (Cap> (C0−ΔC)), the controller 14 makes a negative determination in step 134 (step 134: N), the process proceeds to step 136, and the detection of the change in the capacitance value Cap is continued.

When the controller 14 proceeds to step 136, the controller 14 detects the capacitance value Cap, sets the detected capacitance value Cap to the reference capacitance value Cbase (step 138), and then sets the set reference capacitance value Cbase to the memory 28. By storing, the reference capacity value Cbase is updated (step 140). As the capacitance value Cap set in the reference capacitance value Cbase, the capacitance value Cap after a predetermined time after the change of the capacitance value Cap reaches the capacitance value ΔC may be applied. , The lowest value of the capacitance value Cap within a predetermined time may be applied.

When the controller 14 updates the reference capacitance value Cbase, the controller 14 applies the updated reference capacitance value Cbase and starts the touch detection process (see FIG. 3).

Here, as shown in FIG. 6A, when the capacitance value Cap immediately before the decrease is equal to or higher than the specified capacitance value Cref, the controller 14 sets the capacitance value ΔC as the change capacitance value Cdif1. A high change capacitance value Cdif2 is applied. As a result, in the controller 14, it is suppressed that the updated reference capacitance value Cbase becomes high, and it is suppressed that the controller 14 determines that it is in the non-touch state even though the touch operation is performed. ..

Further, as shown in FIG. 6B, when the capacitance value Cap immediately before the decrease does not reach the specified capacitance value Cref, the controller 14 sets the capacitance value ΔC to be lower than the change capacitance value Cdif2. Apply the value Cdif1. As a result, in the controller 14, it is suppressed that the updated reference capacitance value Cbase becomes lower than necessary, and it is suppressed that the controller 14 determines that it is in the touch state even though the touch operation is not performed. NS.

Further, as shown in FIGS. 6 (A) and 6 (B), by applying the updated reference capacitance value Cbase, it is possible to perform touch determination according to the touch operation. Therefore, the touch detection device 10 can accurately lock and unlock the door of the side door 20 in response to the touch operation of the door handle 22 to the touch operation unit 12.

As described above, in the touch detection device 10, the reference capacitance value Cbase and the threshold value Cth set for the reference capacitance value Cbase are used, and the capacitance value Cap at the sensor electrode 16 of the touch operation unit 12 is the touch operation unit. A touch operation on 12 is detected.

Further, in the touch detection device 10, when the touch operation unit 12 is pressed and held for a long time, the reference capacitance value Cbase is updated. As a result, the touch detection device 10 can update the reference capacitance value Cbase at an arbitrary timing.

At this time, in the touch detection device 10, if the capacitance value Cap when the duration Ts elapses is equal to or higher than the preset predetermined capacitance value Cref, only the preset capacitance value ΔC The capacitance value Cap after the change is set as the reference capacitance value Cbase. As a result, in the touch detection device 10, since the capacitance value ΔC can be secured with respect to the specified capacitance value Cref and the reference capacitance value Cbase can be set, it is possible to prevent the reference capacitance value Cbase from becoming too high and the detection accuracy. Is suppressed from decreasing. Moreover, in the touch detection device 10, it is possible to prevent the time required for updating the reference capacitance value Cbase from becoming long.

Further, in the touch detection device 10, when the capacitance value Cap when the duration Ts elapses is less than the specified capacitance value Cref, the capacitance value ΔC is obtained, and when the capacitance value Cap is equal to or more than the specified capacitance value Cref. Set to a value lower than the capacitance value ΔC of. Therefore, in the touch detection device 10, it is possible to suppress the reference capacitance value Cbase from becoming too low, and it is possible to suppress the occurrence of erroneous determination due to noise or the like.

Further, in the touch detection device 10, the changing capacitance value Cdif1 when the capacitance value Cap is less than the specified capacitance value Cref and the changing capacitance value Cdif2 when the capacitance value Cap is equal to or more than the specified capacitance value Cref are preset. Therefore, it is possible to easily update the appropriate reference capacity value Cbase.

Further, in the touch detection device 10, the maximum value of the capacitance value Cap after the duration Ts has elapsed is set to the initial value C0. As a result, in the touch detection device 10, the reference capacitance value Cbase can be appropriately set even if the way of touching the touch operation unit 12 changes.

Further, in the touch detection device 10, since the capacitance value ΔC is set to a value larger than the difference between the reference capacitance value Cbase and the threshold value Cth, the occupant's touch operation on the touch operation unit 12 can be detected accurately. This makes it possible to more effectively suppress a decrease in the detection accuracy of the touch operation.

In the touch detection device 10, when the capacitance value Cap after the duration Ts of the long press operation on the touch operation unit 12 is less than the specified capacitance value Cref, the change capacitance value Cdif1 is applied as the capacitance value ΔC. Then, the reference capacity value Cbase was updated. However, if the capacitance value Cap after the duration Ts of the long press operation for the touch operation unit 12 is less than the specified capacitance value Cref, the reference capacitance value Cbase is not updated and the length for the touch operation unit 12 is long. The reference capacitance value Cbase may be updated only when the capacitance value Cap after the duration Ts of the pressing operation is equal to or greater than the specified capacitance value Cref.

In the present embodiment described above, the mutual capacitance type touch operation unit 12 has been described as an example. However, the sensor unit may be of a capacitance type, and various configurations can be applied to the sensor unit and the sensor electrodes applied to the sensor unit.

Further, in the present embodiment, the door lock device 24 is connected to the touch detection device 10 to lock / unlock the side door 20 in response to the touch operation of the touch operation unit 12. However, the touch detection device can be used by being connected to various devices to be operated provided with a switch or the like to be operated, and the touch detection device detects a touch operation on the sensor unit to perform the detected operation. The device to be operated can be operated accordingly.

The touch detection device may be provided in the air conditioner of the vehicle, and the air conditioner may be turned on / off, the set temperature may be raised / lowered, the air volume may be increased / decreased, the wind direction may be switched, or the like by touching the sensor unit. When the air conditioner is turned on / off, the switch of the air conditioner is provided with a sensor unit, and the sensor unit is touch-operated to switch between on and off alternately. When used to raise / lower the set temperature of the air conditioner, a sensor unit is provided for each of the up switch and the down switch, the set temperature is raised in a predetermined step each time the up switch is touch-operated, and the down switch is touch-operated. Each time, the set temperature is lowered in a predetermined step.

Further, the touch detection device is provided in the audio device of the vehicle, and the audio device can be turned on / off, the volume can be turned up / down, the radio can be selected, the audio source can be switched, etc. by touching the sensor unit. good. When switching the audio source in the audio device, a sensor unit may be provided in the input changeover switch so that the audio source can be switched in order each time the touch operation of the sensor unit is performed.

It should be noted that various processors other than the CPU may execute the determination process and the update process, which are executed by the CPU reading the software (program) in the above embodiment. In this case, the processor is a PLD (Programmable Logic Device) whose circuit configuration can be changed after manufacturing an FPGA (Field-Programmable Gate Array) or the like, and an ASIC (Application Specific Integrated Circuit) or the like in order to execute a specific process. An example is a dedicated electric circuit or the like, which is a processor having a circuit configuration designed exclusively for the purpose. Further, it may be executed by one of these various processors, or may be executed by a combination of two or more processors of the same type or different types (for example, a plurality of FPGAs and a combination of a CPU and an FPGA). You may. Further, the hardware structure of these various processors is, more specifically, an electric circuit in which circuit elements such as semiconductor elements are combined.

Further, in the present embodiment, the mode in which the programs of the detection process, the determination process, and the update process are stored (installed) in the storage medium (storage) in advance has been described, but the present invention is not limited to this. The program may be provided in a form recorded on a recording medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), and a USB (Universal Serial Bus) memory. Further, the program may be downloaded from an external device via a network.

10 ... Touch detection device, 12 ... Touch operation unit (sensor unit), 14 ... Controller, 16 ... Sensor electrode, 26 ... Detection unit (detection means), 30 ... Judgment unit (Determination means), 32 ... Update unit (update means).

Claims (5)

The sensor unit, which changes the capacitance of the sensor electrode when the operator is close to the sensor electrode,
A detection unit that detects the capacitance value of the sensor electrode and
Using a preset reference value and a threshold value set for the reference value, the operation is performed based on whether or not the capacitance value detected by the detection unit has reached the threshold value. A determination unit that determines whether or not a person is close to the sensor unit,
When the capacitance value detected by the detection unit reaches the threshold value and the capacitance value after a predetermined elapsed time elapses is equal to or higher than a preset specified value, the said. The capacitance value is set to the initial value, and the change in the capacitance value detected by the detection unit with respect to the initial value reaches a preset change capacitance value, and then the capacitance value is newly added. The update part that updates as a standard value, and
Touch detector including. When the capacitance value after the elapsed time elapses is less than the specified value, the renewal unit performs the changing static electricity so that the capacitance value becomes smaller than when the capacitance value is equal to or more than the specified value. This includes setting a capacitance value and updating the capacitance value after the change of the capacitance value detected by the detection unit with respect to the initial value reaches the changed capacitance value as a new reference value. The touch detection device according to claim 1. The first capacitance value as the changed capacitance value when the capacitance value after the elapsed time has elapsed is equal to or greater than the specified value, and the capacitance value after the elapsed time has elapsed. The touch detection device according to claim 2, wherein a second capacitance value as the changed capacitance value when is less than the specified value is preset. The updating unit is claimed from claim 1 in which the maximum value of the capacitance value from the time when the elapsed time has elapsed until the capacitance value detected by the detection unit starts to decrease is set as the initial value. Item 3. The touch detection device according to any one of items 3. The touch detection device according to any one of claims 1 to 4, wherein the changed capacitance value is a capacitance value larger than the difference between the reference value before updating and the threshold value.

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