OPERATION DEVICE

An operation device includes an operation member including a plurality of symbols on a front surface side thereof, plural detection electrodes that are aligned on a back surface side of the operation member and constitute a self-capacitance touch sensor, plural detection electrode groups each including at least one detection electrode predetermined from the plurality of detection electrodes so as to correspond to the shape of the symbol, and a determination unit that is electrically connected to the plurality of detection electrodes and determines, when a sum of capacitances detected by the detection electrodes constituting one of the detection electrode groups is not less than a predetermined first threshold value, that a touch operation is performed on the symbol corresponding to the one detection electrode group.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present patent application claims the priority of Japanese patent application No. 2020/005096 filed on Jan. 16, 2020, and the entire contents of Japanese patent application No. 2020/005096 are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to an operation device.

BACKGROUND ART

A switch device is known which is provided with electrodes having shapes corresponding to icons such as characters/letters or pictograms indicating functions, etc., of the switch (see, e.g., Patent Literature 1).

The electrodes are arranged on a back surface of a decorative panel provided on a right front passenger side door on the inner side of a vehicle and constitute a capacitive sensor.

CITATION LIST

Patent Literature

Patent Literature 1: JP 2006/321336 A

SUMMARY OF INVENTION

In the known switch device, the electrodes have shapes corresponding to the icons. Therefore, when arranged on, e.g., a left front passenger side, not on a right front passenger side, the order of the icons is changed, which means that a common design cannot be used for the right front passenger side and the left front passenger side and it is not efficient in terms of designing.

It is an object of the invention to provide an operation device which can streamline the designing in the switch device.

According to an aspect of the invention, an operation device comprises:an operation member comprising a plurality of symbols on a front surface side thereof;a plurality of detection electrodes that are aligned on a back surface side of the operation member and constitute a self-capacitance touch sensor;a plurality of detection electrode groups each comprising at least one detection electrode predetermined from the plurality of detection electrodes so as to correspond to the shape of the symbol; anda determination unit that is electrically connected to the plurality of detection electrodes and determines, when a sum of capacitances detected by the detection electrodes constituting one of the detection electrode groups is not less than a predetermined first threshold value, that a touch operation is performed on the symbol corresponding to the one detection electrode group.

Advantageous Effects of Invention

According to an embodiment of the invention, it is possible to streamline the designing in the switch device.

DESCRIPTION OF EMBODIMENTS

Short Summary of the Embodiments

An operation device in the embodiments is generally provided with an operation member having plural symbols formed on a front surface side, plural detection electrodes that are aligned on a back surface side of the operation member and constitute a self-capacitance touch sensor, plural detection electrode groups each composed of at least one detection electrode pre-selected from the plural detection electrodes so as to correspond to the shape of the formed symbol, and a determination unit that is electrically connected to the plural detection electrodes and determines, when a sum of capacitances detected by the detection electrodes constituting a given detection electrode group is not less than a predetermined first threshold value, that an operation is performed on a symbol corresponding to the detection electrode group.

In this operation device, the detection electrode groups consisting of at least one detection electrode are pre-assigned to symbols so as to correspond to the shapes of the symbols. Therefore, even if the shapes of the symbols are changed, it is adaptable without changing the shapes of the detection electrode unlike when providing detection electrodes each corresponding to the shape of one symbol. The operation device thereby can streamline the designing.

First Embodiment

(General Configuration of an Operation Device1)

An example of the operation device in the first embodiment will be described below in reference to each drawing. In each drawing of the embodiment described below, a scale ratio may be different from an actual ratio. In addition, inFIG. 1B, flows of main signals and information are indicated by arrows.

FIG. 1Ais a diagram illustrating the inside of a vehicle in which an example of the operation device is mounted andFIG. 1Bis an example block diagram illustrating the operation device. As shown inFIG. 1A, an operation device1is arranged on a center console80of a vehicle8. The operation device1is to operate an electronic device mounted on the vehicle8. As an example, the electronic device is an air conditioner, a navigation device, a music and image reproduction device, or a vehicle control device for making the settings of the vehicle8or controlling the vehicle8. The operation device1in the first embodiment controls an air conditioner82in response to an operation performed by a user, as an example.

FIG. 2Ais a side view showing an example of an operating portion of the operation device. As shown inFIGS. 1B and 2A, the operation device1is generally provided with an operation member11having plural symbols formed on a front surface110side, plural detection electrodes that are aligned on a back surface111side of the operation member11and constitute a self-capacitance touch sensor, plural detection electrode groups each composed of at least one detection electrode pre-selected from the plural detection electrodes so as to correspond to the shape of the formed symbol, and a control unit20as a determination unit that is electrically connected to the plural detection electrodes and determines, when a sum of capacitances detected by the detection electrodes constituting a given detection electrode group is not less than a predetermined first threshold value Th1, that an operation is performed on a symbol corresponding to the detection electrode group.

FIG. 2Bis a diagram illustrating an example of plural symbols formed on the operation member, andFIG. 2Cis an explanatory diagram illustrating an example of a relation between the detection electrodes and the symbols in a right-hand drive vehicle.

As shown inFIG. 2B, the plural symbols are symbols12a-12f, as an example. Meanwhile, as shown inFIG. 2A, the plural detection electrodes are detection electrodes14a-14t, as an example. Then, as shown inFIG. 2C, the plural detection electrode groups are detection electrode groups15a-15f, as an example.

The symbols12a-12fare surrounded by frames13a-13fso that boundaries of regions for accepting a touch operation on the symbol are recognizable. In addition, the symbols12a-12fare fixed to the operation member11. That is, the symbols12a-12fand the frames13a-13fare provided by printing, etc., on the front surface110of the operation member11, as an example.

As shown inFIG. 1B, the operation device1is further provided with a storage portion16and a display portion18. The storage portion16is a semiconductor memory provided on a substrate on which the control unit20is arranged, as an example. The storage portion16stores the first threshold value Th1and detection electrode group information160. The display portion18is a liquid crystal monitor for displaying setting temperature, etc., of the air conditioner82.

In the operation device1, the operation member11and the detection electrodes14a-14tconstitute an operating portion10, as shown inFIG. 2A. The operating portion10and the display portion18are arranged on the center console80, as shown inFIG. 1A. The vehicle8in the first embodiment is a right-hand drive vehicle which has a steering wheel81on the right side. Therefore, the symbols12a-12fare arranged so that it is easy to use for the user sitting in a driver's seat located on the right side.

(Configuration of the Operating Portion10)

The operation member11is formed of a resin material such as polycarbonate and is formed in a plate shape. The front surface110of the operation member11may alternatively be a curved surface.

The detection electrodes14a-14tare formed of a highly conductive metal such as silver. In addition, the detection electrodes14a-14thave the same shape and are arranged side by side at equal intervals, as shown inFIG. 2C.

The width and intervals of the detection electrodes14a-14tare set so that an operating finger is detected by plural detection electrodes. The width of the operating finger is different with each person but is roughly the same. Therefore, the detection electrodes are configured that the width of one individual detection electrode is smaller than the width of the operating finger and the operating finger when touching a portion between at least two detection electrodes is detected by both detection electrodes.

The detection electrodes14a-14tare electrically connected to the control unit20. The detection electrodes14a-14toutput capacitance signals Sa-Stcorresponding to capacitances, to the control unit20. That is, each of the detection electrodes14a-14tacts as a touch sensor which detects a touch operation.

The detection electrodes constitute the detection electrode groups which correspond to the shapes of the symbols. In the first embodiment, the detection electrode groups15a-15fare pre-assigned to the symbols12a-12fThe information of the detection electrodes constituting the detection electrode groups15a-15fis stored as the detection electrode group information160in the storage portion16.

The symbol12arepresents that it is a touch switch with function of adjusting air volume of the air conditioner82. The user can adjust the air volume by firstly performing a touch operation on the symbol12awhile using the frame13aas a guide and then performing another touch operation on the symbol12e(“−”, to reduce the air volume) or the symbol12f(“+”, to increase the air volume). The touch operation on the symbol12ais detected by the detection electrode group15awhich includes the detection electrodes14a-14c.

The symbol12brepresents that it is a touch switch with function of turning on and off the AUTO mode of the air conditioner82. By performing a touch operation on the symbol12bwhile using the frame13bas a guide, the user can activate the air conditioner82in the AUTO mode for automatically adjusting temperature or air volume, or can terminate the AUTO mode. The touch operation on the symbol12bis detected by the detection electrode group15bwhich includes the detection electrodes14d-14g.

The symbol12crepresents that it is a touch switch with function of circulating the air in the vehicle8. By performing a touch operation on the symbol12cwhile using the frame13cas a guide, the user can make the air in the vehicle8circulate or can draw in the external air without circulating. The touch operation on the symbol12cis detected by the detection electrode group15cwhich includes the detection electrodes14h-14k.

The symbol12drepresents that it is a touch switch with function of adjusting the temperature setting of the air conditioner82. The user can adjust the temperature setting by firstly performing a touch operation on the symbol12dwhile using the frame13das a guide and then performing another touch operation on the symbol12e(“−”, to lower the temperature) or the symbol12f(“+”, to increase the temperature). The touch operation on the symbol12dis detected by the detection electrode group15dwhich includes the detection electrodes14l-14o.

The symbol12erepresents that it is a touch switch with function of adjustment to turn down the air volume or temperature setting of the air conditioner82. The touch operation on the symbol12eis detected by the detection electrode group15ewhich includes the detection electrodes14pand14q.

The symbol12frepresents that it is a touch switch with function of adjustment to turn up the air volume or temperature setting of the air conditioner82. The touch operation on the symbol12fis detected by the detection electrode group15fwhich includes the detection electrodes14sand14t.

In the first embodiment, a detection electrode which is not used to constitute the detection electrode groups is included in the detection electrodes14a-14t. As shown inFIGS. 2B and 2C, the symbol12eand the symbol12fare separated in such a manner that the detection electrode14ris sandwiched therebetween. Thus, the detection electrode14ris not used to detect a touch operation.

FIG. 2Dis an explanatory diagram illustrating an example of a relation between the detection electrodes and the symbols in a left-hand drive vehicle. The driver's seat is located on the left side in the left-hand drive vehicle. Therefore, the order of the symbols12a-12fis preferably reversed from that in the right-hand drive vehicle so that it is easy to use for the user sifting in the driver's seat on the left-hand side. Thus, the symbols12a-12fare aligned from left to right on the plane of the paper ofFIG. 2Cin the right-hand drive vehicle but are aligned from right to left on the plane of the paper ofFIG. 2Din the left-hand drive vehicle.

The operation device1detects a touch operation using detection electrode groups, not by detection electrodes each corresponding to the shape of one symbol. Therefore, even when the order of the symbols is changed as shown inFIGS. 2C and 2D, the operation device1can be flexibly adapted by changing the configuration of the detection electrode groups.

(Configuration of the Control Unit20)

The control unit20is, e.g., a microcomputer composed of a CPU (Central Processing Unit) performing calculation and processing, etc., of the acquired data according to a stored program, and a RAM (Random Access Memory) and a ROM (Read Only Memory) as semiconductor memories, etc. The ROM stores, e.g., a program for operation of the control unit20. The RAM is used as, e.g., a storage area for temporarily storing calculation results, etc. The control unit20also has, inside thereof, a means for generating a clock signal, and operates based on the clock signal. The storage portion16may be RAM or ROM of the control unit20.

The control unit20selects detection electrodes from the detection electrodes14a-14tbased on the detection electrode group information160and configures the detection electrode groups15a-15fThe control unit20adds up capacitances detected by the detection electrodes constituting the detection electrode groups, compares the results to the first threshold value Th1, and determines whether or not a touch operation is performed.

FIG. 3Ais a diagram illustrating an example of the operating portion on which a touch operation is performed by the user,FIG. 3Bis a diagram illustrating an example of capacitance of each detection electrode, andFIG. 3Cis a diagram illustrating an example of total capacitance of each detection electrode group. InFIG. 3B, the horizontal axis shows detection electrodes and the vertical axis shows capacitance C. InFIG. 3C, the horizontal axis shows detection electrode groups and the vertical axis shows total capacitance CA. The total capacitance CAhere is a sum of all capacitances detected by detection electrodes constituting a detection electrode group.

As shown inFIG. 3A, when the user performs a touch operation on the “TEMP” symbol12dand the detection electrode group15ddetects an operating finger9indicated by a dashed line, capacitances detected mainly by the detection electrodes14mand14nincrease as shown inFIG. 3B, as an example.FIG. 3Bdepicts that detection electrodes other than those constituting the detection electrode group15ddetect slight capacitance due to exogenous noise, etc.

The control unit20periodically acquires the capacitance signals Sa-Stfrom the detection electrodes14a-14t. Based on the detection electrode group information160, the control unit20adds up capacitances indicated by the capacitance signals Sa-Stfor each of the detection electrode groups15a-15f.

Since the total capacitance CAof the detection electrode group15dwhich detected the operating finger9is more than the first threshold value Th1as shown inFIG. 3C, the control unit20determines that a touch operation is performed on the detection electrode group15d. Then, based on the determination result, the control unit20outputs operation information S1, which indicates that a touch operation is performed on the detection electrode group15d, to the connected air conditioner82.

Next, an operation of the operation device1in the first embodiment will be described along with the flowchart inFIG. 4.

The control unit20of the operation device1acquires the capacitance signals Sa-Stfrom the detection electrodes14a-14tand reads the capacitances C (Step1). Based on the detection electrode group information160acquired from the storage portion16, the control unit20calculates the total capacitance CAof each detection electrode group (Step2).

The control unit20compares the calculated total capacitances CAto the first threshold value Th1acquired from the storage portion16. Then, when there is total capacitance CAwhich is not less than the first threshold value Th1(=Th1≤CA) (Step3: Yes), the control unit20determines that a touch operation is performed.

The control unit20generates the operation information S1including information of the detection electrode group detected the touch operation and outputs the operation information S1to the air conditioner82(Step4), and then proceeds the process to Step1to read capacitances in the next cycle. This operation is continuously performed until the operation device1is turned off.

Meanwhile, when there is no detection electrode group which detected a touch operation in Step3(Step3: No), the control unit20proceeds the process to Step1to read capacitances in the next cycle.

Effects of the First Embodiment

The operation device1in the first embodiment can streamline the designing. In particular, in the operation device1, the detection electrode groups15a-15fare pre-assigned to the symbols12a-12fso as to correspond to the shapes of the symbols12a-12f. Therefore, even if the shapes of the symbols are changed, it is adaptable without changing the shapes of the detection electrodes unlike when providing detection electrodes each corresponding to the shape of one symbol. The operation device1thereby can streamline the designing.

Vehicles, even of the same model, are sometimes manufactured as right-hand drive and left-hand drive depending on which countries the vehicles are marketed. The operation device1can be adapted to the change of the order of the symbols or to a different symbol arrangement, etc., by changing the configuration of the detection electrode groups, no matter which side the steering wheel is on. Therefore, unlike when such a configuration is not adopted, it is not necessary to redesign the arrangement, etc., of the detection electrodes and it is possible to design efficiently.

In case that the front surface110of the operation member11is a flat surface, users often recognize the touch switch area based on symbols such as characters/letters or shapes indicating functions of the touch switch. Then, if each detection electrode is provided so as to correspond to one symbol, every touch switch needs to be designed differently, and in addition to this, it is necessary to newly design when the size or number of the characters/letters of the symbol is changed or the shapes are changed, hence, it is inefficient. In contrast, the operation device1only requires changing the configuration of the detection electrodes so as to correspond to the symbols as described above and thus can streamline the designing.

Second Embodiment

The second embodiment is different from other embodiments in that two threshold values are provided.

FIG. 5Ais an example block diagram illustrating the operation device,FIG. 5Bis a diagram illustrating an example of capacitance of each detection electrode, andFIG. 5Cis a diagram illustrating an example of total capacitance of each detection electrode group. InFIG. 5B, the horizontal axis shows the detection electrodes and the vertical axis shows the capacitance C. InFIG. 5C, the horizontal axis shows the detection electrode groups and the vertical axis shows the total capacitance CA. In addition, the capacitances C and the total capacitances CAshown inFIGS. 5B and 5Care obtained when a touch operation is performed on the detection electrode group15din the same manner as shown inFIG. 3Aof the first embodiment. For the purpose of comparison, the first threshold value Th1is indicated by a dashed line inFIG. 5B.

In the embodiments described below, portions having the same functions and configurations as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment and the explanation therefor will be omitted.

As shown inFIGS. 5A to 5C, the control unit20has a second threshold value Th2smaller than the first threshold value Th1and calculates the sum of the capacitances C of not less than the second threshold value Th2(=the total capacitance CA) for each of the plural detection electrode groups. The second threshold value Th2is stored in the storage portion16but it is not limited thereto. The second threshold value Th2may be stored in the RAM or ROM of the control unit20.

The second threshold value Th2is a threshold for capacitance detected due to exogenous noise, etc. Since the control unit20calculates the total capacitance CAof the detection electrode group including the detection electrodes which detected the capacitances of not less than the second threshold value Th2, processing is faster than when the total capacitances CAof all detection electrode groups are calculated. Therefore, as shown inFIG. 5C, the control unit20calculates the total capacitance CAof only the detection electrode group15dwhere the capacitances C of not less than the second threshold value Th2are detected.

Next, an example of an operation of the operation device1in the second embodiment will be described along with the flowchart inFIG. 6.

The control unit20of the operation device1acquires the capacitance signals Sa-Stfrom the detection electrodes14a-14tand reads the capacitances C (Step10). The control unit20compares the read capacitances C to the second threshold value Th2acquired from the storage portion16.

When the capacitances C of not less than the second threshold value Th2are detected (Step11: Yes), the control unit20calculates the total capacitance CAfor each of the detection electrode groups including the detection electrodes which detected the capacitances C of not less than the second threshold value Th2(Step12).

The control unit20compares the calculated total capacitance CAto the first threshold value Th1acquired from the storage portion16. When there is the total capacitance CAwhich is not less than the first threshold value Th1(=Th1≤CA) (Step13: Yes), the control unit20determines that a touch operation is performed.

The control unit20generates the operation information S1including information of the detection electrode group detected the touch operation and outputs the operation information S1to the air conditioner82(Step14), and then proceeds the process to Step1to read capacitances in the next cycle. This operation is continuously performed until the operation device1is turned off.

Meanwhile, when capacitances C of not less than the second threshold value Th2are not detected in Step11(Step11: No), the control unit20proceeds the process to Step10. Then, when there is no detection electrode group with the total capacitance CAof not less than the first threshold value Th1in Step13(Step13: No), the control unit20proceeds the process to Step10to read capacitances in the next cycle.

Effects of the Second Embodiment

The operation device1in the second embodiment calculates the total capacitance CAfor not all the detection electrode groups but for the detection electrode group including the detection electrodes which detected the capacitances C of not less than the second threshold value Th2. Therefore, the operation device1can efficiently determine a touch operation and can perform the processing faster.

Third Embodiment

The third embodiment is different from the other embodiments in that detection electrodes are arranged two-dimensionally.

FIG. 7Ais a diagram illustrating an example of the plural symbols two-dimensionally arranged on the operation member, andFIG. 7Bis an explanatory diagram illustrating an example of a relation between the detection electrodes and the symbols in a right-hand drive vehicle. InFIG. 7BandFIG. 7C(described later), symbols120a-120kshown inFIG. 7Aare denoted next to detection electrode groups150a-150k. In addition, inFIGS. 7B and 7C, frames130a-130kare indicated by dashed lines.

As shown inFIG. 7A, the symbols120a-120khaving various sizes and shapes are provided on the operation device1in the third embodiment. The symbols120a-120kare surrounded by the frames130a-130kso that boundaries of regions for accepting a touch operation on the symbol are recognizable.

In the operation device1, the detection electrodes14a-14tare arranged in a lower row as viewed inFIGS. 7B and 7Cand detection electrodes140a-140tare arranged in an upper row. The detection electrodes14a-14tand the detection electrodes140a-140thave the same shape and are arranged at equal intervals as an example, but it is not limited thereto.

The symbols120aand120bhave shapes extending across the upper and lower rows. A touch operation on the symbol120ais detected by the detection electrode group150awhich includes the detection electrodes14a-14cand the detection electrodes140a-140c. Meanwhile, a touch operation on the symbol120bis detected by the detection electrode group150bwhich includes the detection electrodes14l-14oand the detection electrodes140l-140o.

The symbols120c-120ghave shapes extending across some of the detection electrodes in the upper row. A touch operation on the symbol120cis detected by the detection electrode group150cwhich includes the detection electrodes140d-140f. A touch operation on the symbol120dis detected by the detection electrode group150dwhich includes the detection electrodes140gand140h. A touch operation on the symbol120eis detected by the detection electrode group150ewhich includes the detection electrode140j. A touch operation on the symbol120fis detected by the detection electrode group150fwhich includes the detection electrodes140pand140q. A touch operation on the symbol120gis detected by the detection electrode group150gwhich includes the detection electrodes140sand140t.

The symbols120h-120khave shapes extending across some of the detection electrodes in the lower row. A touch operation on the symbol120his detected by the detection electrode group150hwhich includes the detection electrodes14d-14g. A touch operation on the symbol120iis detected by the detection electrode group150iwhich includes the detection electrodes14h-140k. A touch operation on the symbol120jis detected by the detection electrode group150jwhich includes the detection electrodes14pand14q. A touch operation on the symbol120kis detected by the detection electrode group150kwhich includes the detection electrodes14sand14t.

The detection electrodes14r,140i,140kand140rare detection electrodes which are not used to constitute any detection electrode group.

Meanwhile, the symbol120dis a symbol which includes a portion of the detection electrode140gand a portion of the detection electrode140h, as shown inFIG. 7B. Since the shape of the operating finger does not change, the operation device1can determine whether or not a touch operation is performed based on the total capacitance CAobtained by adding up the capacitances C detected by the detection electrode140gand the detection electrode140hof the detection electrode group150d.

Furthermore, with the symbol120e, the detection electrode group150econsists of one detection electrode (=the detection electrode140j). The operation device1uses the capacitance C detected by the detection electrode140jas the total capacitance CAand determines whether or not a touch operation is performed.

FIG. 7Cis an explanatory diagram illustrating an example of a relation between the detection electrodes and the symbols in a left-hand drive vehicle. The driver's seat is located on the left side in the left-hand drive vehicle. Therefore, the symbols120a-120kare aligned from left to right on the plane of the paper ofFIG. 7Bin the right-hand drive vehicle but are aligned from right to left on the plane of the paper ofFIG. 7Cin the left-hand drive vehicle.

Thus, the configuration of the detection electrode groups150a-150kis different betweenFIG. 7BandFIG. 7C. The detection electrode group150acorresponding to the symbol120ain the right-hand drive vehicle is composed of the detection electrodes14a-14cand the detection electrodes140a-140c. On the other hand, the detection electrode group150acorresponding to the symbol120ain the left-hand drive vehicle is composed of the detection electrodes14r-14tand the detection electrodes140r-140t. Since the control unit20changes the configuration of the detection electrode groups150a-150kbased on the detection electrode group information160, it is possible to flexibly adapt to the change in design.

The operation device1detects a touch operation using detection electrode groups, not by detection electrodes each corresponding to the shape of one symbol. Therefore, even when the order of the symbols is changed as shown inFIGS. 7B and 7C, the operation device1can be flexibly adapted by changing the configuration of the detection electrode groups.

Effects of the Third Embodiment

The operation device1in the third embodiment does not require changing the size or arrangement of the detection electrodes even when the symbols are arranged two-dimensionally. Therefore, it is possible to flexibly adapt to change in design.

The operation device1in at least one of the above-described embodiments streamline the designing.

Some portions of the operation device1in the embodiments and modifications may be realized by, e.g., a computer executable program, ASIC (Application Specific Integrated Circuit) and FPGA (Field-Programmable Gate Array), etc., according to the intended use.

Although some embodiments of the invention have been described, these embodiments are merely examples and the invention according to claims is not to be limited thereto. These new embodiments may be implemented in various other forms, and various omissions, substitutions and changes, etc., can be made without departing from the gist of the invention. In addition, all combinations of the features described in these embodiments are not necessary to solve the problem of the invention. Further, these embodiments are included within the scope and gist of the invention and also within the invention described in the claims and the range of equivalency.

REFERENCE SIGNS LIST