JP7190632B2 - Cooking device and method of controlling the cooking device - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a cooking device that heats food and a control method for the cooking device.

An example of a cooking device is a microwave oven. In this microwave oven, the user presses a button for starting heating after inputting the heating time and the like. Thereby, heat cooking is performed. In particular, stores such as convenience stores and supermarkets sometimes provide a service of selling packed lunches and side dishes in containers, and cooking the purchased food using a microwave oven.

However, such a microwave oven has a problem that it is troublesome for the user to input the heating time and the like each time. Therefore, when the store becomes crowded, the user may press the operation start button even if the object to be heated is not properly placed in the heating chamber. In this case, heating control is performed while the inside of the refrigerator is empty.

In response to this, techniques for preventing dry heating and the like have been proposed.

For example, in Patent Document 1, a camera is mounted on a heat cooker, and before cooking, the inside of the refrigerator is photographed with this camera, and the degree of similarity between the photographed image and a pre-registered image of the inside of the refrigerator is is calculated, and if it is a predetermined similarity, it is determined that the inside of the refrigerator is empty.

However, in the technique described in Patent Document 1, the state of the interior of the refrigerator can be accurately determined based on only the similarity of the difference images in the interior of the refrigerator, where the state of the interior changes depending on usage conditions, such as dirt on the bottom of the interior due to broth, sauce, and the like. difficult to do

JP 2015-137812 A

The present disclosure solves the conventional problems described above, and accurately detects the state of the inside of the refrigerator without being affected by whether the inside is empty or whether the surface of the refrigerator is dirty or not, and whether the surface is dirty or not. To provide a heating cooker and a method for controlling the heating cooker capable of

The heating cooker includes a heating chamber for storing an object to be heated, first lighting and second lighting for illuminating the inside of the heating chamber, a photographing unit provided in the heating chamber, and an image of the inside of the heating chamber using the photographing unit. and an image capturing control unit for generating an image, and a heating control unit for heating the inside of the heating chamber. The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and controls the photographing unit and the first and the second illumination are operated to capture a second image under a second illumination condition different from the first illumination condition. The heating controller heats the interior of the heating chamber based on the relationship between the first image and the second image.

A control method of a heating cooker comprises: a heating chamber for storing an object to be heated; a first illumination and a second illumination for illuminating the interior of the heating chamber; A control method for a heating cooker including an imaging control section and a heating control section for heating the inside of a heating chamber. Then, the imaging control unit uses at least one of the first lighting and the second lighting to capture the first image in the heating chamber under the first lighting condition. The imaging control unit uses at least one of the first illumination and the second illumination to capture a second image of the inside of the heating chamber under a second illumination condition different from the first illumination condition. . The heating controller heats the interior of the heating chamber based on the relationship between the first image and the second image.

According to the present disclosure, a heating cooker that can accurately detect the state of the inside of the refrigerator not only when the inside is empty but also without being affected by the presence or absence and the size of stains on the surface of the refrigerator. and a method for controlling a heating cooker.

FIG. 1 is a perspective view showing the appearance of the heating cooker according to the first embodiment of the present disclosure. FIG. 2 is a diagram showing a schematic configuration of the heating cooker according to the first embodiment of the present disclosure. FIG. 3 is a cross-sectional view seen from above inside the heating chamber, showing an example of the arrangement of the lighting of the heating cooker according to the first embodiment of the present disclosure. FIG. 4 is a diagram showing an in-fridge image (in-fridge empty image) registered in the storage unit of the cooker according to the first embodiment of the present disclosure. FIG. 5 is a diagram illustrating an example of an interior image of a heating cooker in a state in which an object to be heated (dirt, etc.) is present in the interior of the heating cooker according to the first embodiment of the present disclosure. FIG. 6 is a diagram illustrating an example of an interior image of a state in which an object to be heated (such as food) is placed in the interior of the heating cooker according to the first embodiment of the present disclosure. FIG. 7 is a diagram showing an example of a photographed image when an object is present in the cooking chamber of the heating cooker and an example of a difference image in the process according to the first embodiment of the present disclosure. FIG. 8 is a diagram showing an example of a photographed image and a difference image in the process when dirt exists in the cooking chamber of the heating cooker according to the first embodiment of the present disclosure. FIG. 9 is a diagram illustrating an example of a table of determination criteria based on image difference comparison values according to the first embodiment of the present disclosure. FIG. 10 is a flow chart showing the operation of detecting the state of the heating chamber of the heating cooker in the first embodiment of the present disclosure. FIG. 11 is a diagram illustrating an example of a photographed image and a difference image in the process when an object is present in the heating chamber according to the second embodiment of the present disclosure. FIG. 12 is a flowchart showing the operation of detecting the state of the heating chamber of the heating cooker in the second embodiment of the present disclosure.

A heating cooker according to a first aspect of the present disclosure includes a heating chamber that stores an object to be heated, first lighting and second lighting that illuminate the inside of the heating chamber, an imaging unit provided in the heating chamber, A photographing control unit that photographs the inside of the heating chamber using the photographing unit to generate an image, and a heating control unit that heats the inside of the heating chamber are provided. Then, the photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph the first image under the first illumination condition, the photographing unit, At least one of the first illumination and the second illumination is operated to capture a second image under a second illumination condition different from the first illumination condition, and the heating control unit performs the first The inside of the heating chamber is heated based on the relationship between the first image and the second image.

According to this configuration, in a heating chamber in which the internal conditions constantly change due to aging and usage conditions, the photographing by the photographing unit mounted in the heating chamber is synchronized with the switching of a plurality of lighting conditions by lighting control. and analyze shadow differences due to changes in lighting conditions. As a result, the state of the inside of the refrigerator can be detected more accurately and the heating can be appropriately controlled without being affected not only by the fact that the inside of the refrigerator is empty, but also by the presence or absence and size of stains on the surface of the refrigerator.

A second aspect is that in the first aspect, based on the relationship between the shadow areas appearing in the first image and the second image, it is determined whether or not there is an object to be heated in the heating chamber, A comparison determination unit may be provided that notifies the heating control unit of the heating conditions according to the determination result.

As a result, it is possible to accurately detect the empty state without being affected by the presence or size of dirt on the surface of the heating chamber, which is constantly changing due to aging and usage conditions. can.

A third aspect is the second aspect, wherein the comparison and determination unit compares a difference comparison value between the first image and a sky image captured using the first illumination, and compares the first image and the second image. It may be determined that there is an object to be heated in the heating chamber based on the relationship between and the difference comparison value.

As a result, the user can be further notified to clean the inside of the heating chamber, and the inside of the heating chamber can be kept clean.

According to a fourth aspect, in the second aspect, the comparison determination section may estimate the volume of the object to be heated based on the size of the shadow area.

As a result, when it is determined that the heating chamber is empty, the safety can be further improved by not only prohibiting heating but also restricting heating according to the volume of the object.

According to a fifth aspect, in the second aspect, the comparison determination section may estimate the height of the object to be heated based on the length of the shadow region.

As a result, safety and usability can be further enhanced by a method such as changing the heating method according to the height of the object.

According to a sixth aspect, in the fourth aspect, the comparison/determination unit may compare the set heating time with a predetermined criterion based on the estimated volume.

As a result, even if the volume of the object to be heated is erroneously set for a heating time that causes overheating, this can be prevented.

A seventh aspect is the first aspect, wherein the heating control unit calculates the result of calculation of the first image and the image of the sky state captured using the first illumination condition, the second image, and the second image. The inside of the heating chamber may be heated based on the relationship between the image of the empty state photographed using the lighting conditions of , and the calculation result.

As a result, the state of the inside of the refrigerator can be detected more accurately and the heating can be appropriately controlled without being affected by the presence or absence and size of stains on the surface of the refrigerator.

An eighth aspect is a heating chamber for storing an object to be heated, a first illumination and a second illumination for illuminating the inside of the heating chamber, and an imaging unit for photographing the inside of the heating chamber to generate an image. A control method for a heating cooker including a control unit and a heating control unit for heating the inside of a heating chamber. Then, the shooting control unit shoots the first image under the first illumination condition using at least one of the first illumination and the second illumination. The imaging control unit uses at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition. The heating controller heats the interior of the heating chamber based on the relationship between the first image and the second image.

As a result, in the heating chamber, where the interior condition constantly changes due to aging and usage conditions, the interior condition can be detected more accurately without being affected by the presence or size of dirt on the surface of the chamber. The inside of the heating chamber can be properly heated and controlled.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid unnecessary verbosity in the following description and to facilitate understanding by those skilled in the art.

It should be noted that the accompanying drawings and the following description are provided for a thorough understanding of the present disclosure by those skilled in the art and are not intended to limit the claimed subject matter.

(First embodiment)
A heating cooker according to a first embodiment of the present disclosure will be described below with reference to the drawings.

In the embodiments, a microwave oven 100 is used as an example of a cooking device.

FIG. 1 is a diagram showing the appearance of microwave oven 100 according to the first embodiment of the present disclosure.

A microwave oven 100 shown in FIG. 1 includes a housing 101 and a door 102 pivotally supported on the housing 101 so as to be openable and closable. Inside the housing 101, there is a heating chamber 201 for storing foods to be heated, such as lunch boxes and side dishes.

Door 102 has a transparent glass window 103 so that the user can see the inside of housing 101 . Further, the door 102 has a handle 104 so that the door 102 can be easily grasped by the user.

In the present embodiment, the side of housing 101 on which door 102 is located is defined as the front, the right side as viewed from the front is defined as right, and the left side is defined as left.

An operation display unit 105 is arranged next to the door 102 . The operation display unit 105 has a liquid crystal display 106 , a time setting button group 107 , a heating start button 108 , a cancel button 109 and a temporary stop button 110 . The user can set the heating time by using the numeric buttons and the minute and second buttons. Also, the liquid crystal display 106 displays the set heating time and the like.

The heating start button 108 is a button for starting heating after the user confirms the heating time, wattage, etc. on the liquid crystal display 106 .

The cancel button 109 is a button for stopping the heating after the user presses the heating start button 108 to start heating. Also, the cancel button 109 may be a button for canceling the setting of the heating time displayed on the liquid crystal display 106 .

The pause button 110 is a button for the user to temporarily stop heating during heating. When the user presses the heating start button 108 again after the heating is temporarily stopped, the rest of the heating can be performed from the middle.

The microwave oven 100 includes two magnetrons 202a and 202b for outputting microwaves in a heating chamber 201 as heating units (heaters).

The magnetron 202a is arranged on the ceiling side of the heating chamber 201 and outputs microwaves into the heating chamber 201 from above. On the other hand, the magnetron 202b is arranged on the bottom side of the heating chamber 201 and outputs microwaves into the heating chamber 201 from below. Food such as boxed lunches and side dishes, that is, objects to be heated 203 (see FIG. 2) stored in the heating chamber 201 are heated by the radiated microwaves.

In addition, in the present disclosure, a magnetron-based microwave is exemplified as a heating unit, but heating may be performed by at least one of a heater, hot air, and steam.

A camera 204 (an example of an imaging unit) is arranged on the ceiling side of the heating chamber 201 . The camera 204 includes an imaging element such as a CCD (Charge Coupled Device) and an optical element such as a lens, and photographs the interior of the heating chamber 201 to generate an image. In the generated image, for example, the brightness of each pixel is represented by a value ranging from 0 (dark) to 255 (bright).

Note that each pixel may be generated as an image represented by a value from 0 to 255 for each color of red, blue, and green. Also, the value corresponding to each pixel may be represented by a range other than 0 to 255 and by a representation method.

Note that, in this embodiment, the camera 204 is provided on the ceiling side surface of the heating chamber 201 . However, camera 204 may be provided on other surfaces such as the side of heating chamber 201 .

It should be noted that, in the present disclosure, as will be described later, by devising lighting conditions, even if the photographing unit 204 is composed of one camera member, the image recognition accuracy can be improved. Therefore, it is possible to reduce manufacturing costs and reduce the size of the housing 101 . However, the imaging unit 204 may be composed of a plurality of camera members.

On the side surface of the heating chamber 201, illumination 205a (first illumination) and illumination 205b (second illumination) using LEDs as light sources are arranged. Illumination 205 a (first illumination) and illumination 205 b (second illumination) illuminate the interior of heating chamber 201 .

In the present embodiment, the lighting 205a is arranged so as to face the inside of the heating chamber 201 from the left side of the heating chamber 201, and the lighting 205b is arranged so as to face the inside of the heating chamber 201 from the right side of the heating chamber 201. . However, the lights 205a and 205b may be arranged on any of the four sides, the ceiling, the bottom, or the like.

Further, each of the lighting 205a and the lighting 205b may have a configuration in which the lighting conditions for illuminating the interior of the heating chamber 201 can be switched between two or more types. For example, one physical light source may be used, and the optical path may be branched into two paths by at least one of an optical fiber and a mirror to illuminate the heating chamber 201 from different directions. Alternatively, one light-emitting element may be used to switch lighting conditions by at least one of ON/OFF of lighting and control of intensity of luminance. Also, the position and angle of the illumination may be changed by motor control or the like. Also, the illumination conditions may be switched depending on at least one of the color tone of the illumination and the irradiation focus. Also, a plurality of lighting conditions may be switched by using three or more light sources.

In the present embodiment, the configuration using LEDs is disclosed as the light source of illumination 205a and illumination 205b. Light sources that generate infrared rays may be used for the illuminations 205a and 205b. By using infrared rays as a light source, it is possible to cope with a case where the bottom surface absorbs visible light, for example, a black surface.

The control unit 300 is arranged below the operation display unit 105 . Control unit 300 controls each component of microwave oven 100 .

FIG. 2 is a schematic configuration diagram of microwave oven 100 in the first embodiment.

The control unit 300 has a heating control unit 301 , a comparison determination unit 302 , an imaging control unit 303 and a storage unit 304 .

Note that, in the present embodiment, the control unit 300 includes the heating control unit 301, the comparison determination unit 302, the imaging control unit 303, and the storage unit 304 in an integrated configuration. However, these configurations may be realized by separate semiconductor elements or the like. Also, the control unit 300 may be configured by a microcomputer such as a CPU (Central Processing Unit).

The heating controller 301 controls the magnetrons 202a and 202b. An object to be heated 203 housed in the heating chamber 201 is heated by the microwaves radiated by the magnetrons 202a and 202b.

The photographing control unit 303 performs ON/OFF control and intensity control of the lighting 205a and the lighting 205b, and photographing control of the camera 204 in synchronization with the lighting control.

A storage unit 304 stores an image in the heating chamber 201 captured by the imaging control unit 303 using the camera 204 .

A comparison determination unit 302 uses the camera 204 to photograph the inside of the heating chamber 201 by the photographing control unit 303 and compares and analyzes the images stored in the storage unit 304 . Thereby, the comparison/determination unit 302 recognizes the state inside the heating chamber 201, detects the state of objects such as food, the presence or absence of the objects, and the presence or absence of stains, and estimates the volume and height.

FIG. 3 is an example showing a configuration of lighting 205a and lighting 205b and the interior of heating chamber 201 in plan view.

FIG. 3 is a view of the bottom side of the heating chamber 201 viewed from the ceiling side. The bottom side in FIG. 3 is the front side with the door 102 . In FIG. 3, as an example, the object 203 to be heated is stored in the bottom surface of the heating chamber 201 .

In this embodiment, the lighting 205a is arranged outside the left side wall of the heating chamber 201, and the optical axis La of the lighting chamber 205a passes through a hole provided in the side wall of the heating chamber 201. facing the direction A light 205b is arranged on the outside of the right side wall of the heating chamber 201, and its optical axis Lb faces substantially the center (including the center) of the heating chamber 201 through a hole provided in the side wall.

By illuminating the interior of the heating chamber 201 with the illumination 205a or the illumination 205b, a shadow area S for the object 203 to be heated can be generated.

A shadow area Sa appears on the bottom right side of the object 203 to be heated by illuminating the heating chamber 201 from the left side with the illumination 205a. In addition, the lighting 205b illuminates the heating chamber 201 from the right side, so that the shadow area Sb appears on the left bottom surface of the object 203 to be heated.

By arranging the illumination 205a and the illumination 205b so that the angle (θ in FIG. 3) formed by the optical axis La and the optical axis Lb becomes large, shadow area Sa and shadow area Overlapping of Sb can be reduced. As a result, it is possible to improve the recognition accuracy based on the image difference, which will be described later. Therefore, it is preferable that the angle formed by the optical axis La and the optical axis Lb is 90 degrees or more.

In the present embodiment, lighting 205a and lighting 205b illuminate heating chamber 201 from the rear to the front. As a result, it is possible to reduce the influence of unnecessary shadow components on the shadow region S due to illumination of the environment in which the microwave oven 100 is installed entering through the door 102 .

That is, a clearer shadow area S can be produced in the front side of the heating chamber 201 than in the case where a shadow area is produced in the rear side. However, the arrangement configuration of the lighting 205a and the lighting 205b does not have to be limited to this optical axis direction.

In the present disclosure, a first lighting condition in which illumination 205a is mainly used is lighting condition C1. A second lighting condition in which the lighting 205b is mainly used is set to lighting condition C2. That is, the illumination condition C1 is an illumination condition for preferentially lighting the illumination 205a, and the illumination condition C2 is an illumination condition for preferentially lighting the illumination 205b.

Here, lighting preferentially means, for example, lighting the lighting 205a with a higher luminance than the lighting 205b and lighting the lighting 205b with a lower luminance than the lighting 205a under the lighting condition C1. may

In this way, each of the illumination conditions C1 and C2 may be any illumination condition that makes it easy to distinguish between the shadow area Sa and the shadow area Sb.

FIG. 4 is a diagram showing an example of an image of the inside of the heating chamber 201 captured in the storage unit 304. As shown in FIG.

In this example, an example of an image is shown in which the inside of the heating chamber 201 is in an “empty state”, that is, the heating target object 203 such as food is not stored in the heating chamber 201 . It should be noted that a reference image in the “empty state” (hereinafter referred to as “empty image”) as shown in the example of FIG. Further, the sky image described above may be generated and stored in the storage unit 304 in a usage environment after shipment from the factory. By generating a sky image under the usage environment, the lighting conditions in the environment in which the microwave oven 100 is installed and the effects of deterioration over time in the heating chamber 201 are reflected more appropriately, thereby improving the image recognition accuracy. can be improved.

5 and 6 are diagrams showing examples of other images captured inside the heating chamber 201. FIG.

In this example, FIG. 5 shows a non-heating object (planar dirt, foreign matter, etc.) in the heating chamber 201, and FIG. ) are present, and an example of an image of the inside of the heating chamber 201 in each case is shown.

FIG. 7 is a diagram showing an example of a photographed image when an object (heating object 203) is present in the heating chamber 201 and a difference image in the process of the processing.

In FIG. 7, (a) is a diagram showing a photographed image under illumination condition C1. In FIG. 7A, the interior of the heating chamber 201 is illuminated from the rear left side by the illumination 205a, so that a shadow area Sa appears on the front right side of the object 203 to be heated.

(b) of FIG. 7 shows a photographed image under illumination condition C2. In FIG. 7B, the inside of the heating chamber 201 is illuminated from the rear right side by the lighting 205b, so that a shadow region Sb appears on the front left side of the object 203 to be heated.

(c) of FIG. 7 shows an image obtained by binarizing the difference between the sky image stored in the storage unit 304 and the image of (a) of FIG. That is, a difference calculation is performed for each pixel between the sky image and the image of (a) in FIG. The difference binarized image shown in FIG. 7(c) is represented by "0" or "1".

As an example, let 20 be the predetermined threshold value for binarization when each pixel of an image is represented by a value ranging from 0 to 255. FIG. In this case, pixels with a difference value of 20 or more gradations between the sky image and the image in FIG. It is represented by a value of 0. Note that the representation method of each pixel and the predetermined threshold value for binarization may be determined as appropriate. Thus, by comparing the image of (a) of FIG. 7 with the sky image, an image from which the influence of the heating chamber 201 is excluded can be generated.

(d) of FIG. 7 shows a binarized difference image between the sky image and the image of (b) of FIG. The difference calculation and binarization methods are the same as in the case of FIG. 7(c).

FIG. 7(e) shows a difference image between the images of FIG. 7(c) and FIG. 7(d). 7C and 7D, the absolute value of the difference is calculated and displayed for each pixel.

In FIG. 7E, only the shadow area Sa and the shadow area Sb by the object to be heated 203 are extracted. Thus, by using the difference between the two images using the two illumination conditions, the heating chamber 201 and the object to be heated 203 can be excluded, and the portion of the shadow region S can be extracted more accurately.

In the image in FIG. 7A taken inside the heating chamber 201 under the illumination condition C1 and in the image in FIG. 7B taken inside the heating chamber 201 under the illumination condition C2, the illumination 205a and lighting 205b. For example, in (a) of FIG. 7, the area near the lighting 205a is brighter, in (b) of FIG. Shading and the like may occur. If a difference is calculated between these images, unnecessary differences other than the object to be heated 203 and the shadow region S appear, which may adversely affect the extraction of the object to be heated 203 and the shadow region S.

On the other hand, in the present disclosure, in generating the images of (c) and (d) of FIG. 7 , by comparing with the sky image, the inside of the heating chamber 201 due to the difference in the two lighting conditions The effect of image difference can be reduced.

FIG. 8 shows an example of a photographed image when dirt D is present in the heating chamber 201 and an example of a difference image in the process.

In FIG. 8, (a) of FIG. 8 shows a photographed image under illumination condition C1. In FIG. 8, illumination is applied from the back left side, but the shadow area S does not appear because the dirt D is planar.

(b) of FIG. 8 shows a photographed image under illumination condition C2. In FIG. 8, illumination is applied from the far right side, but the shadow area S does not appear because the dirt D is planar.

(c) of FIG. 8 shows a binarized difference image between the sky image and the image of (a) of FIG. (d) of FIG. 8 shows a binarized difference image between the sky image and the image of (b) of FIG.

FIG. 8(e) shows a difference image between the images of FIG. 8(c) and FIG. 8(d). Here, since the dirt D is planar, the shadow region S is not extracted.

FIG. 9 is a diagram showing an example of a table that defines the criteria for determining the internal state of the refrigerator and for determining whether or not heating is possible.

Here, a feature amount representing the degree of difference between two images is defined as a difference comparison value. In the present embodiment, a difference is calculated for each pixel between two images, each difference value is compared with a predetermined threshold value for binarization, and in the binarized image, the value is Let the total number of pixels that are 1 be the difference comparison value.

Also, a binarized difference image between the sky image and the image to be determined under illumination condition C1 is defined as a difference image P1, and a difference comparison value is defined as a difference comparison value A1. Similarly, a binarized difference image between the sky image and the determination target image under illumination condition C2 is defined as a difference image P2, and a difference comparison value is defined as a difference comparison value A2. Further, a difference comparison value B is defined as a difference comparison value between the difference image P1 and the difference image P2.

The comparison determination unit 302 compares each difference comparison value with a predetermined image difference threshold to determine the state of the heating chamber 201 and whether or not heating is possible.

The table in FIG. 9 is used to determine whether the inside of the heating chamber 201 is empty, an object (an object to be heated), or dirty, based on the relationship between the difference comparison value A1 and the difference comparison value B. shows a standard example of

In the example of FIG. 9, the comparison determination unit 302 determines whether the inside of the heating chamber 201 is empty by comparing the difference comparison value A1 with the first image difference threshold value (here, the value is 200). When the difference comparison value A1 is smaller than the first image difference threshold value, the comparison determination unit 302 determines that the difference value is due to the noise component of the image and the like, and that the heating chamber 201 is empty. In this case, the comparison determination unit 302 determines that the heating chamber 201 cannot be heated.

In addition, the comparison determination unit 302 further compares the difference comparison value B with a second image difference threshold value (here, 500) to determine whether or not an object exists in the heating chamber 201 . When the difference comparison value B is larger than the second image difference threshold, the comparison determination unit 302 determines that there is a shadow component of the object, that is, the object 203 to be heated is present in the heating chamber 201 . In this case, the comparison determination unit 302 determines that the heating chamber 201 can be heated. On the other hand, when the difference comparison value B is small, the comparison/determination unit 302 determines that there is a component that is not the object to be heated, that is, there is dirt D or the like. In this case, the comparison determination unit 302 determines that the heating chamber 201 cannot be heated. Furthermore, if necessary, control unit 300 notifies the user of the presence of non-heatable objects such as dirt and foreign matter.

In this embodiment, the first image difference threshold is set to 200, and the second image difference threshold is set to 500. However, each value may be selected as appropriate.

In the present embodiment, when the images are compared to generate a binarized image, the luminance difference in each pixel is counted when it exceeds a predetermined value. However, the image difference can be extracted. If so, any method may be used, and the image similarity, the difference due to the color of each pixel, and the like may be used.

Further, in the present embodiment, the difference comparison value under the illumination condition C1 is defined as the difference comparison value A1, but the difference comparison value A1 may be the difference comparison value under the illumination condition C2, It may be a difference comparison value under a third illumination condition different from C2.

FIG. 10 is a flow chart showing the state detection operation of the heating chamber 201 of the microwave oven 100 in the first embodiment.

A detailed description will be given below with reference to the flow chart of FIG.

In step S1, the imaging control unit 303 controls the lighting 205a and lighting 205b to switch to the lighting condition C1 (for example, only the left lighting 205a is ON), and the process proceeds to step S2.

In step S2, the photographing control unit 303 controls the camera 204 to photograph the interior of the heating chamber 201, the photographed image is stored in the storage unit 304, and the process proceeds to step S3. When there is an object (heating object 203) in the refrigerator, the photographed image becomes an image in which the object has a shadow area S as shown in FIG. 7(a). If there is no object in the refrigerator and there is dirt D, the photographed image will be an image without the shadow area S, as shown in FIG. 8(a).

In step S3, the comparison/determination unit 302 calculates the difference between the sky image under illumination condition C1 stored in advance in the storage unit 304 and the image captured in step S2, and the process proceeds to step S4.

(c) of FIG. 7 and (c) of FIG. 8 are examples of the binarized image after calculating the difference in step S3. Note that the difference value calculated in step S3 corresponds to the difference comparison value A1 in FIG.

In step S4, the comparison/determination unit 302 determines whether or not the inside of the heating chamber 201 is empty from the difference value calculated in step S3 according to the determination criteria of the table of FIG. If the determination criteria in FIG. 9 are applied, when the difference value is 200 or less (S4, YES), the comparison/determination unit 302 determines that the inside of the refrigerator is empty. Based on this determination, the process ends without heating. If the difference value is 201 or more (S4, NO), it is determined that there is an object or dirt in the refrigerator, and the process proceeds to step S5.

In step S5, the imaging control unit 303 controls the lighting 205a and lighting 205b to switch to lighting condition C2 (for example, only the right lighting 205b is ON), and the process proceeds to step S6.

In step S6, the photographing control unit 303 controls the camera 204 to photograph the inside of the heating chamber 201, the photographed image is stored in the storage unit 304, and the process proceeds to step S7. If there is an object in the refrigerator, the photographed image will be an image in which the object is shaded, as shown in FIG. 6(b). If there is no object in the refrigerator and the refrigerator is dirty, the photographed image will be an image without the shadow area S, as shown in FIG. 8(b).

In step S7, the comparison determination unit 302 calculates the difference between the sky image under illumination condition C2 stored in advance in the storage unit 304 and the image captured in step S6, and the process proceeds to step S8. (d) of FIG. 7 and (d) of FIG. 8 are examples of the binarized image after calculating the difference in step S7.

In step S8, the comparison determination unit 302 performs difference calculation between the difference image calculated in step S3 and the difference image calculated in step S7, and the process proceeds to step S9. (e) of FIG. 6 and (e) of FIG. 8 are examples of the difference image calculated in step S8.

When there is an object, that is, a three-dimensional object, in the heating chamber 201, the difference in the shadow area S due to the lighting conditions C1 and C2 appears as a difference, as shown in FIG. 7(e). On the other hand, if the inside of the refrigerator is dirty, that is, if there is a non-three-dimensional object, there is no difference in shadows due to the illumination conditions C1 and C2, so the difference is almost non-existent as shown in FIG. 8(e). Even when the inside of the refrigerator is completely empty without dirt, the result of the difference is as shown in FIG.

In step S9, the comparison/determination unit 302 determines the state inside the heating chamber 201 from the difference value calculated in step S3 and the difference value calculated in step S8 according to the determination criteria of the table in FIG. For example, when the difference comparison value A1 is 201 or more and the difference comparison value B is 501 or more, it is determined that "an object is detected". Then, the process proceeds to step S10, and heating is performed. On the other hand, when the difference comparison value A1 is 201 or more and the difference comparison value B is 500 or less, it is determined that "inside dirt (empty) is detected", and the process proceeds to step S11.

In step S11, the user is notified of the state of dirt inside the refrigerator, and the process ends without performing heating.

In the present embodiment, the criteria and thresholds shown in FIG. 9 are merely examples, and the values are not limited, and may be freely set at the time of manufacture or at the time of use. The number of divisions of the table may also be increased from that in FIG. 9 to determine the size of objects and stains. Similarly, the criteria for determining whether or not heating is possible for each determination result of the state in the heating chamber 201 are not limited to the criteria in FIG. good.

In the present embodiment, an example was given in which the illumination condition C1 is set to "only the left illumination is ON" and the illumination condition C2 is set to "only the right illumination is ON". Any other combination may be used as long as it can produce a difference in . For example, the lighting condition C1 may be set to "both left and right lighting OFF (only outside light incident from the glass window 103)", and the lighting condition C2 may be set to "only the right lighting ON". Alternatively, the illumination condition C1 may be set to "the left illumination is ON and the illumination direction is the first angle", and the illumination condition C2 is "the left illumination is ON and the illumination direction is the second angle".

As described above, according to the present embodiment, in the heating cooker in which the state in the heating chamber 201 constantly changes due to aging, usage conditions, etc., the presence or absence and size of stains on the chamber surface can be , it is possible to detect the empty state exactly. In addition, since it is not necessary to update the reference sky image when performing difference comparison, simple operation is possible and stable interior state determination can be realized.

(Second embodiment)
11A and 11B are diagrams showing an example of a photographed image and a difference image in the process when an object exists in the heating chamber 201 according to the second embodiment of the present disclosure. (a) to (e) of FIG. 11 are the same as those of FIGS. 7 (a) to (e) in the first embodiment.

FIG. 12 is a flowchart showing the operation of detecting the state of the heating chamber of the heating cooker in the second embodiment of the present disclosure.

The second embodiment will be described below with reference to the flowchart of FIG.

The main difference between the first embodiment and the second embodiment is that in the second embodiment, when it is determined that there is an object in the heating chamber 201 in step S9, the object to be heated 203 is The point is that the volume is estimated, and the validity of the set heating time is determined for the estimated volume.

In the following, differences from the first embodiment will be mainly described, and detailed descriptions of the points in which the same control is performed will be omitted.

The lighting conditions C1 and C2 in the present embodiment are a combination that allows only the shadow region S to be extracted when the difference between the captured images is calculated. For example, the illumination condition C1 turns on both the lights 205a and 205b attached to the left and right side surfaces of the heating chamber 201, and the illumination condition C2 turns on only the left light 205a. Under illumination condition C1, the left and right illuminations 205a and 205b cancel each other's shadows formed on the objects in the heating chamber 201, so that the shadows do not appear on the captured image or become faint as shown in FIG. 11(a). . On the other hand, under illumination condition C2, the shadow of the object appears clearly in the captured image, as shown in FIG. 11(b). Therefore, by calculating the difference between the captured images under these illumination conditions C1 and C2, only the shadow area S is extracted, and the size of the shadow can be measured. Note that other combinations of the illumination conditions C1 and C2 may be used as long as the shadow region S can be extracted.

In step S9, when the comparison determination unit 302 determines that there is an object, the process proceeds to step S12.

In step S12, the comparison/determination unit 302 calculates the difference between the difference image in step S3 ((c) in FIG. 11) and the difference image in step S7 ((d) in FIG. 11). Extract the shadow region S as in e). Next, the length of the shadow region S is appropriately multiplied by a correction coefficient corresponding to the position in the heating chamber 201 to obtain the height of the target object. The difference area ((c) in FIG. 11) calculated in step S3 corresponds to the area of the object in plan view, which is multiplied by the height to calculate the volume, and the process proceeds to step S13.

In step S13, the comparison determination unit 302 compares the volume estimated in step S12 and the heating time set by the user to determine validity. For example, if a relatively long heating time is set with respect to the criteria described later, such as 1500 W and 10 minutes for a volume of a normal rice ball sold at a convenience store, it is reasonable. It is determined that the heating time is not set.

This criterion may be defined as a function that represents the upper and lower limits of a reasonable range of heating setting time for volume, or the volume is divided into several ranges and the corresponding reasonable heating time range may be defined in a table. When the comparison determination unit 302 determines that the set heating time is appropriate, the process proceeds to step S10 and heating is started. If the comparison determination unit 302 determines that the set heating time is inappropriate, the process proceeds to step S14.

In step S14, it is notified that the set heating time is not appropriate for the volume of the object to be heated 203, and the process ends without heating.

In the present embodiment, when the comparison and determination unit 302 determines that the heating time is not appropriate, the heating is prohibited. It is not limited to this. For example, the heating itself may be performed only by notifying that it is inappropriate, or the heating may be stopped at the upper limit heating time according to the volume of the object 203 to be heated.

In this manner, according to the present embodiment, it is possible to estimate the volume of the object to be heated 203 from the size of the shadow region S extracted by combining images captured under a plurality of illumination conditions. . In addition, even if the heating time is erroneously set so as to overheat the volume of the object 203 to be heated, the safety can be improved by prohibiting or limiting the heating. can.

Also, in the present embodiment, the volume is estimated from the shadow area S. FIG. However, the height of the object to be heated 203 may be estimated from the length of the shadow region S. Specifically, for example, for the shadow region S, the length of the shadow region S from the center of the object to be heated 203 in the axial direction of the illumination is calculated. Then, the height of the object to be heated 203 can be estimated from this length and the angle between the axial direction of the lights 205 a and 205 b and the bottom surface of the heating chamber 201 . By performing imaging control and heating control based on the estimated height of the object 203 to be heated, the state recognition and heating in the heating chamber 201 can be performed more appropriately.

As described above, according to the heating cooker and the control method of the heating cooker of the present disclosure, by more accurately detecting the state of the inside of the refrigerator, heating is performed under appropriate heating conditions, and the can prevent the danger of overheating. In addition, even if there is dirt, the user can be prompted to remove it easily, and the user can heat and cook the food cleanly and safely.

(Other embodiments)
Another embodiment of the embodiment described above will be described.

It is also possible to configure a heating cooker such as a microwave oven to be connectable to a network, and implement it as a heating cooking system in which a server on the network controls the heating cooker. In such a cooking system, both or one of the processes performed by the comparison/determination unit 302 and the storage unit 304 in the microwave oven 100 of the first embodiment is performed on the server side. This makes it possible to reduce the processing load due to recognition processing and the like in the heating cooker.

It should be noted that the above-described embodiments are intended to illustrate the technology in the present disclosure, and therefore various modifications, replacements, additions, omissions, etc. may be made within the scope of the claims or equivalents thereof. can.

According to the present disclosure, it is possible to accurately detect the state of the inside of the refrigerator without being affected by whether the inside is empty or whether the surface of the refrigerator is dirty or not, and whether the surface is dirty or not. As a result, the present invention is widely applicable and useful not only to microwave ovens used in shops, but also to household microwave ovens, rice cookers, IH cooking heaters, and the like.

100 microwave oven (cooking device)
101 Case 102 Door 103 Glass Window 104 Handle 105 Operation Display Unit 106 Liquid Crystal Display 107 Time Setting Button Group 108 Heating Start Button 109 Cancel Button 110 Pause Button 201 Heating Chamber 202a, 202b Magnetron 203 Object to be Heated 204 Camera (Photographing Unit )
205a, 205b lighting 300 control unit 301 heating control unit 302 comparison determination unit 303 imaging control unit 304 storage unit A1, A2, B difference comparison value D dirt La, Lb optical axis S, Sa, Sb shadow area

Claims (8)

a housing;
a heating chamber for storing an object to be heated in the housing;
a door having a window through which the inside of the heating chamber can be seen, the door being pivotally supported in the housing so as to be openable and closable;
a first lighting and a second lighting that illuminate the interior of the heating chamber from the rear to the front;
an imaging unit provided in the heating chamber;
a photographing control unit that photographs the interior of the heating chamber using the photographing unit and generates an image;
A heating control unit that heats the inside of the heating chamber,
The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and operating the unit and at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition;
The heating control unit heats the interior of the heating chamber based on the relationship between shadow areas appearing in the first image and the second image. Determining whether or not the object to be heated exists in the heating chamber based on the relationship between shadow areas appearing in the first image and the second image, and depending on the result of the determination, A comparison determination unit that notifies the heating control unit of a heating condition,
The heating cooker according to claim 1. a heating chamber for storing an object to be heated;
a first lighting and a second lighting that illuminate the interior of the heating chamber;
an imaging unit provided in the heating chamber;
a photographing control unit that photographs the interior of the heating chamber using the photographing unit and generates an image;
A heating control unit that heats the inside of the heating chamber,
The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and operating the unit and at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition;
In the heating cooker, the heating control unit heats the inside of the heating chamber based on the relationship between the first image and the second image,
Determining whether or not the object to be heated exists in the heating chamber based on the relationship between shadow areas appearing in the first image and the second image, and depending on the result of the determination, A comparison determination unit that notifies the heating control unit of a heating condition,
The comparison determination unit determines a difference comparison value between the first image and a sky image captured using the first illumination and a difference comparison value between the first image and the second image. Based on the relationship, determine that there is an unheated object in the heating chamber;
heating cooker. a heating chamber for storing an object to be heated;
a first lighting and a second lighting that illuminate the interior of the heating chamber;
an imaging unit provided in the heating chamber;
a photographing control unit that photographs the interior of the heating chamber using the photographing unit and generates an image;
A heating control unit that heats the inside of the heating chamber,
The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and operating the unit and at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition;
In the heating cooker, the heating control unit heats the inside of the heating chamber based on the relationship between the first image and the second image,
Determining whether or not the object to be heated exists in the heating chamber based on the relationship between shadow areas appearing in the first image and the second image, and depending on the result of the determination, A comparison determination unit that notifies the heating control unit of a heating condition,
The comparison determination unit estimates the volume of the object to be heated based on the size of the shadow area.
heating cooker. a heating chamber for storing an object to be heated;
a first lighting and a second lighting that illuminate the interior of the heating chamber;
an imaging unit provided in the heating chamber;
a photographing control unit that photographs the interior of the heating chamber using the photographing unit and generates an image;
A heating control unit that heats the inside of the heating chamber,
The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and operating the unit and at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition;
In the heating cooker, the heating control unit heats the inside of the heating chamber based on the relationship between the first image and the second image,
Determining whether or not the object to be heated exists in the heating chamber based on the relationship between shadow areas appearing in the first image and the second image, and depending on the result of the determination, A comparison determination unit that notifies the heating control unit of a heating condition,
The comparison determination unit estimates the height of the object to be heated based on the length of the shadow region.
heating cooker. The comparison determination unit compares the heating setting time with a predetermined determination criterion based on the estimated volume.
The heating cooker according to claim 4. a housing;
a heating chamber for storing an object to be heated in the housing;
a door having a window through which the inside of the heating chamber can be seen, the door being pivotally supported in the housing so as to be openable and closable;
a first lighting and a second lighting that illuminate the interior of the heating chamber from the rear to the front;
an imaging unit provided in the heating chamber;
a photographing control unit that photographs the interior of the heating chamber using the photographing unit and generates an image;
A heating control unit that heats the inside of the heating chamber,
The photographing control unit operates the photographing unit and at least one of the first illumination and the second illumination to photograph a first image under a first illumination condition, and operating the unit and at least one of the first illumination and the second illumination to capture a second image under a second illumination condition different from the first illumination condition;
In the heating cooker, the heating control unit heats the inside of the heating chamber based on the relationship between the first image and the second image,
The heating control unit captures a result of calculation of the first image and an image of an empty state captured using the first illumination condition, and the second image using the second illumination condition. Heating the inside of the heating chamber based on the relationship between the calculation result and the image of the empty state obtained ,
heating cooker. A housing, a heating chamber for storing an object to be heated in the housing, a door pivotally supported in the housing and having a window through which the inside of the heating chamber can be seen, and the inside of the heating chamber to the rear. a first lighting unit and a second lighting unit that illuminate the interior of the heating chamber toward the front; a photographing control unit that photographs the interior of the heating chamber using an imaging unit to generate an image; and a heating control unit that heats the interior of the heating chamber. A control method for a heating cooker comprising
The imaging control unit captures a first image of the inside of the heating chamber under a first lighting condition using at least one of the first lighting and the second lighting,
The imaging control unit uses at least one of the first illumination and the second illumination to set the second illumination in the heating chamber under a second illumination condition different from the first illumination condition. take an image of
The heating control unit heats the interior of the heating chamber based on the relationship between shadow areas appearing in the first image and the second image.
A control method for a heating cooker.

Images