JP7793440B2 - Input device and cooking appliance - Google Patents

Description

The present invention relates to an input device that accepts information input and a cooking appliance equipped with the input device.

Capacitive touch panels are known in the art. Capacitive touch panels have multiple electrode patterns. Each electrode pattern has an electrode portion and a wiring portion extending from the electrode portion. When a user presses an electrode portion, the capacitance of the electrode pattern including that electrode portion changes. By detecting this change in capacitance, information input is detected.

Conventional capacitive touch panels are described, for example, in Patent Documents 1 and 2.

Japanese Patent Application Laid-Open No. 2012-243513 Japanese Patent Application Laid-Open No. 2014-216075

However, with capacitive touch panels, the capacitance of the electrode pattern changes not only when the electrode section is pressed, but also when the wiring section is pressed. As a result, a change in capacitance is detected even when the wiring section is pressed at a position away from the electrode section. This can result in information not intended by the user being input.

To prevent such erroneous input, it is possible to accept information input only when the change in capacitance exceeds a specified reference value. However, the change in capacitance depends on the area of the electrode pattern that is pressed. Therefore, when a person with thin fingers presses the electrode portion, the change in capacitance may be similar to when a person with thick fingers presses the wiring portion. In such cases, it becomes difficult to appropriately set the reference value.

The present invention was developed in consideration of these circumstances, and aims to provide technology that can prevent unintended information from being input when a user accidentally presses the wiring portion of a capacitive touch panel.

The present invention provides an input device for receiving information input, comprising a capacitive touch panel and a control unit electrically connected to the touch panel. The touch panel has a plurality of electrode patterns, each having an electrode portion and a wiring portion extending from the electrode portion, with at least two of the plurality of wiring portions arranged in close proximity. The control unit detects information input based on changes in the capacitance of the electrode patterns, and invalidates the input if the difference in the amount of change in capacitance between two electrode patterns including the two wiring portions is smaller than a preset threshold.

According to the present invention, when two closely spaced wiring sections are pressed, the input is invalidated. This prevents unintended information from being entered when the user accidentally presses a wiring section.

The distance between the two wiring sections is preferably 0.5 mm or more and 5 mm or less. This makes it difficult for a person's finger to press only one of the two wiring sections. Therefore, when an area near the two wiring sections is pressed, there is a high probability that the difference in the amount of change in capacitance will be below the threshold. This further reduces the risk of erroneous information being entered.

At least one of the two wiring sections may extend between the two electrode sections. In this case, when a user attempts to press an electrode section, there is a possibility that the user may also press the wiring section at the same time. However, in this case, the amount of change in capacitance of the electrode pattern including the electrode section will be significantly greater than the amount of change in capacitance of the electrode pattern including the wiring section. Therefore, by appropriately setting the threshold value, it is possible to validate the input of information by pressing the electrode section, as intended by the user.

In particular, when multiple electrode units are arranged in a matrix of three or more rows, the wiring unit extending from the inner electrode unit of the two wiring units extends outward, passing between the other electrode units. In this case, when a user attempts to press an electrode unit, there is a possibility that the user may press the wiring unit at the same time. However, by setting the threshold appropriately, it is possible to validate the input of information by pressing the electrode unit, as intended by the user.

The touch panel also preferably has a display panel disposed in front of the electrode unit, and the display panel preferably displays multiple buttons, and the display panel preferably does not display a common button on the front of one of the two electrode units connected to the two wiring units and the other electrode unit. In other words, the buttons on the liquid crystal display panel preferably are displayed in such a way that it is not necessary to simultaneously press both electrode units connected to the two wiring units. This prevents input from being invalidated when a single button is pressed.

It is also desirable that the cooking appliance be equipped with the above-mentioned input device.

According to the present invention, when two closely spaced wiring sections are pressed, the input is invalidated. This prevents unintended information from being entered when the user accidentally presses a wiring section.

FIG. 1 is a perspective view of a rice cooker equipped with an input device. FIG. FIG. 2 is a plan view of an electrode sheet. FIG. 2 is a plan view of a display panel. 10 is a flowchart showing a procedure of an input process.

Embodiments of the present invention will be described below with reference to the drawings.

<1. Rice cooker configuration>
Fig. 1 is a perspective view of a rice cooker 1 equipped with an input device 2 according to one embodiment of the present invention. The rice cooker 1 is an apparatus for cooking rice, an ingredient, together with water. In other words, the rice cooker 1 is an example of a cooking appliance for cooking ingredients. As shown in Fig. 1, the rice cooker 1 includes a main body 10, a lid 20, a heating unit 30, a touch panel 40, and a control unit 50.

The main body 10 is a container that can accommodate an inner pot (not shown). The inner pot is made of a metal that can be induction heated. When using the rice cooker 1, the inner pot is placed in a recess provided inside the main body 10.

The lid 20 is rotatably connected to the main body 10 by a hinge located at the rear of the main body 10. The lid 20 rotates about the hinge between a closed position (the position shown in Figure 1) in which it covers the top of the main body 10, and an upright position in which it stands approximately perpendicular to the main body 10. When the inner pot is placed on the main body 10 and the lid 20 is in the closed position, the opening at the top of the inner pot is closed by the lid 20. This seals the interior space of the inner pot.

The heating unit 30 is a means for heating the inner pot. The heating unit 30 is provided inside the main body 10. For example, an induction heating coil is used for the heating unit 30. When the rice cooker 1 is in use, a high-frequency current is supplied to the induction heating coil, which generates magnetic field lines. This causes the inner pot to heat up due to electromagnetic induction, heating the rice and water contained inside the inner pot.

The rice cooker 1 may further include a pressure adjustment unit that adjusts the pressure in the internal space of the inner pot when the inner pot is heated by the heating unit 30.

The touch panel 40 is a panel that the user of the rice cooker 1 operates to input information. In the example of FIG. 1, the touch panel 40 is provided on the top surface of the lid body 20. However, the touch panel 40 may also be provided on the outer surface of the main body 10. The touch panel 40 displays images of various buttons related to the operation of the rice cooker 1. The user of the rice cooker 1 inputs information by pressing the button images displayed on the touch panel 40.

The detailed structure of the touch panel 40 will be described later.

The control unit 50 is a means for controlling the operation of the rice cooker 1. In the example of FIG. 1, the control unit 50 is provided inside the lid body 20. However, the control unit 50 may also be provided inside the main body 10. The control unit 50 is configured, for example, by a circuit board equipped with a microcomputer. The control unit 50 is electrically connected to the heating unit 30 and the touch panel 40. The control unit 50 controls the display on the touch panel 40, the input of information from the touch panel 40, and the operation of the heating unit 30 according to a preset program.

2. Configuration of input device
The touch panel 40 and the control unit 50 described above constitute an input device 2 that accepts information input from a user. The input device 2 will be described in more detail below.

Figure 2 is an exploded perspective view of the touch panel 40. This touch panel 40 is a so-called capacitive touch panel that detects information input based on changes in capacitance detected when a user's finger presses the touch panel 40. As shown in Figure 2, the touch panel 40 has an electrode sheet 41 equipped with multiple electrode patterns 60, and a display panel 42. The display panel 42 is disposed on the front surface of the electrode sheet 41 (the top surface in this embodiment).

Figure 3 is a plan view of the electrode sheet 41. As shown in Figures 2 and 3, the electrode sheet 41 has multiple electrode patterns 60 formed by continuous conductors. Each electrode pattern 60 has one rectangular electrode portion 61 and a wiring portion 62 extending from the electrode portion 61. The multiple electrode patterns 60 are insulated from each other.

The multiple electrode units 61 are arranged in a multi-row, multi-column matrix with spaces between them. In this embodiment, a case where 18 electrode units 61 are arranged in a 3-row, 6-column matrix is described. In Figure 3, the display area A, which is the portion of the display panel 42 that is exposed to the outside, is indicated by a two-dot chain line. The multiple electrode units 61 are arranged in positions that overlap this display area A.

The wiring portion 62 is a thin wire-like portion extending from the electrode portion 61. The line width of the wiring portion 62 is sufficiently smaller than the length of one side of the electrode portion 61. One end of the wiring portion 62 is connected to the electrode portion 61. The other end of the wiring portion 62 extends to the outside of the display area A. The other end of the wiring portion 62 is electrically connected to the control unit 50 directly or via another electrical wiring. In other words, the control unit 50 and the electrode portion 61 are electrically connected via the wiring portion 62.

In the following, the six electrode portions 61 in the first row from the top in FIG. 3 will be referred to as "first electrode portions 61a," the six wiring portions 62 extending from the first electrode portions 61a will be referred to as "first wiring portions 62a," the six electrode portions 61 in the second row from the top in FIG. 3 will be referred to as "second electrode portions 61b," the six wiring portions 62 extending from the second electrode portions 61b will be referred to as "second wiring portions 62b," the six electrode portions 61 in the third row from the top in FIG. 3 will be referred to as "third electrode portions 61c," and the six wiring portions 62 extending from the third electrode portions 61c will be referred to as "third wiring portions 62c."

Furthermore, hereinafter, the electrode pattern 60 composed of the first electrode portion 61a and the first wiring portion 62a will be referred to as the "first electrode pattern 60a," the electrode pattern 60 composed of the second electrode portion 61b and the second wiring portion 62b will be referred to as the "second electrode pattern 60b," and the electrode pattern 60 composed of the third electrode portion 61c and the third wiring portion 62c will be referred to as the "third electrode pattern 60c."

Furthermore, below, the direction in which three electrode units 61 in the same column are arranged will be referred to as the "column direction."

In the example of FIG. 3, the six first wiring portions 62a each extend from the first electrode portion 61a toward one side in the column direction (the side opposite the second electrode portion 61b and the third electrode portion 61c). The six second wiring portions 62b each extend from the second electrode portion 61b toward the other side in the column direction (the side opposite the first electrode portion 61a). The six third wiring portions 62c each extend from the third electrode portion 61c toward the other side in the column direction (the side opposite the first electrode portion 61a and the second electrode portion 61b).

Furthermore, the second wiring portion 62b extending from the second electrode portion 61b and the third wiring portion 62c extending from the third electrode portion 61c in the same column as the second electrode portion 61b extend parallel to and in close proximity to each other within the display area A. Specifically, the second wiring portion 62b and the third wiring portion 62c are arranged with a distance d between them that is sufficiently smaller than the thickness of the average human fingertip.

The line width of the first wiring portion 62a, the second wiring portion 62b, and the third wiring portion 62c within the display area A is, for example, 0.5 mm or more and 5 mm or less. Furthermore, the distance d between the closely arranged second wiring portion 62b and the third wiring portion 62c is, for example, 0.5 mm or more and 5 mm or less.

Figure 4 is a plan view of the display panel 42. The display panel 42 may be, for example, a liquid crystal display panel. As shown in Figure 4, the control unit 50 displays images of multiple buttons 70 on the display panel 42. The multiple buttons 70 are displayed in positions that overlap with the multiple electrode units 61. Each button 70 represents a different command that the user can input when operating the rice cooker 1.

Some of the multiple buttons 70 (buttons (1) to (5) in the example of Figure 4) 70 have a size equivalent to two or more electrode units 61 and are displayed in front of two or more electrode units 61. Furthermore, another button (button (6) in the example of Figure 4) 70 has a size equivalent to one electrode unit 61 and is displayed in front of one electrode unit 61. The control unit 50 can also switch the type of button 70 displayed on the display panel 42.

<3. Input processing>
Next, a description will be given of the procedure for inputting information in the input device 2. Fig. 5 is a flowchart showing the procedure for the input process.

When the power is on in this rice cooker 1, the control unit 50 constantly monitors whether the capacitance of the electrode patterns 60 on the electrode sheet 41 has changed. Specifically, the control unit 50 monitors whether the amount of change in capacitance for at least one electrode pattern 60 has become greater than a predetermined reference value (step S1). This reference value is pre-stored in the control unit 50. If the amount of change in capacitance is equal to or less than the reference value (step S1: No), the control unit 50 continues monitoring in step S1.

When a user of the rice cooker 1 presses a button 70 on the display panel 42, the capacitance of the electrode pattern 60, including the electrode portion 61 on the back side of the button 70, changes. Depending on where the user presses, only one electrode pattern 60 may be pressed, or two or more electrode patterns 60 may be pressed. If the change in capacitance of at least one electrode pattern 60 is greater than the reference value (Step S1: Yes), the control unit 50 then performs the determination process of Step S2.

In step S2, the control unit 50 determines whether the capacitance of both the second electrode pattern 60b and the third electrode pattern 60c has changed (step S2). If the capacitance of both the second electrode pattern 60b and the third electrode pattern 60c has not changed (step S2: No), the control unit 50 validates the information input by the operation (step S3).

For example, if the capacitance of only one electrode pattern 60 has changed in step S2, the control unit 50 validates the information input by that electrode pattern 60. In other words, the control unit 50 executes the command indicated by the button 70 pressed by the user.

Furthermore, even if the number of electrode patterns 60 whose capacitance has changed is two or more, if the combination of electrode patterns 60 is not the combination of the second electrode pattern 60b and the third electrode pattern 60c, the input of information from the electrode pattern 60 with the largest change in capacitance is validated. In other words, the control unit 50 executes the command indicated by the button 70 corresponding to the electrode part 61 of the electrode pattern 60 with the largest change in capacitance.

If, in step S2, both the capacitance of the second electrode pattern 60b and the capacitance of the third electrode pattern 60c have changed (step S2: Yes), the control unit 50 then performs the determination process of step S4.

In step S4, the control unit 50 determines whether the difference between the amount of change in capacitance of the second electrode pattern 60b and the amount of change in capacitance of the third electrode pattern 60c is smaller than a predetermined threshold value (step S4). This threshold value is stored in advance in the control unit 50.

If the difference between the amount of change in capacitance of the second electrode pattern 60b and the amount of change in capacitance of the third electrode pattern 60c is equal to or greater than the threshold value (step S4: No), the control unit 50 validates the input of information from the electrode pattern 60 with the larger amount of change in capacitance out of the second electrode pattern 60b and the third electrode pattern 60c (step S3). That is, the control unit 50 executes the command indicated by the button 70 corresponding to the electrode part 61 of the electrode pattern 60 with the larger amount of change in capacitance out of the second electrode pattern 60b and the third electrode pattern 60c.

On the other hand, if the difference between the amount of change in capacitance of the second electrode pattern 60b and the amount of change in capacitance of the third electrode pattern 60c is smaller than the threshold value (step S4: Yes), the control unit 50 invalidates the information input by that operation (step S5). In other words, the control unit 50 does not execute the command indicated by any of the buttons 70.

<4. Examples of preventing incorrect input>
By executing the above input process, the input device 2 can prevent erroneous input of information. An example of preventing erroneous input achieved by the above input process will be described below.

<4-1. First example>
When the user presses a position where the second wiring portion 62b and the third wiring portion 62c are closely arranged, as in position P1 in Figure 4, the capacitance of both the second electrode pattern 60b and the third electrode pattern 60c changes. However, because the second wiring portion 62b and the third wiring portion 62c are closely arranged, the amount of change in capacitance of the second electrode pattern 60b and the amount of change in capacitance of the third electrode pattern 60c are close to each other. Therefore, in step S4 described above, the difference in the amount of change in capacitance is smaller than the threshold value, and the information input by this operation is invalid.

In this way, if a user accidentally presses position P1 while trying to press button 70 (4) in Figure 4, a change in the capacitance of the second electrode pattern 60b will prevent erroneous input, such as the command for button 70 (1) being validated.

In particular, the distance d between the second wiring portion 62b and the third wiring portion 62c is 0.5 mm or more and 5 mm or less, as described above. This makes it difficult for a person's finger to press only one of the second wiring portion 62b and the third wiring portion 62c. Therefore, when a press is made near position P1, there is a high probability that the difference between the amount of change in capacitance of the second electrode pattern 60b and the amount of change in capacitance of the third electrode pattern 60c will be below the threshold. This further reduces the risk of erroneous information being entered.

<4-2. Second example>
When the user presses position P2 at the boundary between two third electrode portions 61c within the area of button 70 (4), the user also simultaneously presses the second wiring portion 62b that passes through this position. In this case, the capacitance of both the second electrode pattern 60b and the third electrode pattern 60c changes. However, in this case, the pressed area of the third electrode portion 61c is sufficiently larger than the pressed area of the second wiring portion 62b. Therefore, the amount of change in capacitance of the third electrode pattern 60c is sufficiently larger than the amount of change in capacitance of the second electrode pattern 60b. Therefore, in step S4 described above, the difference in the amount of change in capacitance is larger than the threshold, and the information input by this operation is deemed valid.

This prevents the command from being invalidated even when the user presses within the area of button 70 (4).

When multiple electrode units 61 are arranged in a matrix of three or more rows, as in this embodiment, the wiring units 62 extending from the inner electrode units 61 must pass between the other electrode units 61. As a result, when a user attempts to press an electrode unit 61, there is a possibility that the user may also press the wiring unit 62 at the same time. However, by appropriately setting the threshold value, as described above, it is possible to enable the input of information by pressing the electrode units 61 as intended by the user.

<4-3. Third example>
When the user presses position P3 on the boundary between button (2) 70 and button (5) 70, the capacitance of both the second electrode pattern 60b and the third electrode pattern 60c changes. However, if the difference between the pressed area of the second electrode portion 61b and the pressed area of the third electrode portion 61c is small, the difference in the amount of change in capacitance in step S4 described above becomes smaller than the threshold. Therefore, the information input by this operation is invalid.

In this way, if a user accidentally presses position P3 while trying to press button 70 (2) in Figure 4, a change in capacitance of the third electrode pattern 60c can be prevented, thereby preventing an erroneous input in which the command for button 70 (5) is validated. Alternatively, if a user accidentally presses position P2 while trying to press button 70 (5) in Figure 4, a change in capacitance of the second electrode pattern 60b can be prevented, thereby preventing an erroneous input in which the command for button 70 (2) is validated.

<4-4. Fourth example>
If the user presses position P4 at the boundary between the first electrode portion 61a and the second electrode portion 61b within the area of button 70 (2), the capacitance of both the first electrode pattern 60a and the second electrode pattern 60b will change. However, in this case, it is determined in step S2 above that the capacitance of the third electrode pattern 60c has not changed. Therefore, the information input by this operation is considered valid.

This prevents the command from being invalidated even when the user presses within the area of button 70 (2).

As such, in this embodiment, a common button 70 is not displayed in front of the second electrode portion 61b and the third electrode portion 61c, which are connected to the closely arranged second wiring portion 62b and third wiring portion 62c. In other words, the display of the buttons 70 on the display panel 42 is designed so that it is not necessary to press the second electrode portion 61b and the third electrode portion 61c simultaneously. This prevents input from being invalidated when pressing within the area of a single button 70.

5. Modified Examples
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

<5-1. First Modified Example>
In the above embodiment, the second wiring portion 62b extends to the other side in the column direction, and the second wiring portion 62b and the third wiring portion 62c are disposed adjacent to each other. However, the second wiring portion 62b may extend to one side in the column direction, and the first wiring portion 62a and the second wiring portion 62b may be disposed adjacent to each other. In this case, the control unit 50 may invalidate the input when the difference between the amount of change in capacitance of the first electrode pattern 60a and the amount of change in capacitance of the second electrode pattern 60b is smaller than a threshold value.

<5-2. Second Modified Example>
Alternatively, the first wiring portion 62 a, the second wiring portion 62 b, and the third wiring portion 62 c may all extend in the same direction. The three wiring portions 62, i.e., the first wiring portion 62 a, the second wiring portion 62 b, and the third wiring portion 62 c, may be disposed close to each other. In this case, the control unit 50 focuses on two electrode patterns 60 with large capacitance changes among the first electrode pattern 60 a, the second electrode pattern 60 b, and the third electrode pattern 60 c, and invalidates the input when the difference in capacitance change between them is smaller than a threshold value.

<5-3. Third Modified Example>
In the above embodiment, 18 electrode units 61 are arranged in a matrix of 3 rows and 6 columns on the electrode sheet 41. However, the number of electrode units 61 arranged on the electrode sheet 41 and the arrangement are not limited to those in the above embodiment. For example, the arrangement of the electrode units 61 may be 4 rows and 5 columns, or 3 rows and 7 columns, etc. Furthermore, the arrangement of the multiple electrode units 61 does not necessarily have to be in a matrix. For example, no electrode unit 61 may be arranged in some of the multiple positions arranged in multiple rows and columns, and multiple electrode units 61 may be arranged in the remaining positions.

<5-4. Other Modifications>
In the above embodiment, the rice cooker 1 has been described as an example of a cooking appliance. However, the cooking appliance of the present invention may be one that heats and cooks ingredients other than rice. Cooking appliances such as the rice cooker 1 often have a large number of cooking menus set up. For this reason, it is necessary to display a large number of buttons 70 in a matrix on the touch panel 40. By adopting the configuration of the above embodiment, it is possible to realize an input device 2 that displays a large number of buttons 70 in a matrix on the touch panel 40 and reduces input errors.

However, the input device 2 of the present invention may also be installed in other home appliances such as air purifiers, hot plates, toaster ovens, coffee makers, rice cake makers, dish dryers, electric kettles, humidifiers, and air purifiers.

Furthermore, the elements appearing in the above embodiments and variations may be combined as appropriate to the extent that no contradictions arise.

1. Rice cooker (cooking appliance)
2 Input device 10 Main body 20 Cover 30 Heating unit 40 Touch panel 41 Electrode sheet 42 Display panel 50 Control unit 60 Electrode pattern 60a First electrode pattern 60b Second electrode pattern 60c Third electrode pattern 61 Electrode unit 61a First electrode unit 61b Second electrode unit 61c Third electrode unit 62 Wiring unit 62a First wiring unit 62b Second wiring unit 62c Third wiring unit 70 Button A Display area

Claims (5)

An input device that accepts input of information,
A capacitive touch panel,
a control unit electrically connected to the touch panel;
Equipped with
The touch panel is
An electrode portion;
a wiring portion extending from the electrode portion;
a plurality of electrode patterns each having
At least two of the plurality of wiring portions are arranged close to each other,
The control unit
Detecting input of information based on a change in capacitance of the electrode pattern;
When the capacitances of the two electrode patterns including the two wiring portions have both changed and the difference between the amounts of change in capacitance of the two electrode patterns including the two wiring portions is smaller than a preset threshold value, performing an invalidation process to invalidate the input;
When the capacitances of two or more electrode patterns in a combination different from the two electrode patterns including the two wiring portions have both changed, the invalidation process is not performed,
The touch panel is
a display panel disposed at a position overlapping the electrode portion;
and
the display panel displays a plurality of buttons;
An input device in which a common button is not displayed at a position overlapping one of the two electrode portions connected to the two wiring portions and at a position overlapping the other electrode portion . 2. The input device according to claim 1,
An input device, wherein the distance between the two wiring portions is 0.5 mm or more and 5 mm or less. 3. The input device according to claim 1,
An input device, wherein at least one of the two wiring portions extends between the two electrode portions. 4. The input device according to claim 3,
The plurality of electrode portions are arranged in a matrix of three or more rows,
An input device, wherein at least one of the two wiring portions extends from an inner electrode portion to an outer portion, passing between the other electrode portion. A cooking appliance comprising the input device according to any one of claims 1 to 4 .