Dishwasher and customized washing method thereof

Abstract

The present specification relates to a dishwasher and a customized washing method for a dishwasher. A customized washing method for a dishwasher according to one embodiment of the present specification includes the steps of performing a first stroke, calculating a first temperature value of a dishware contained in a rack when the first stroke is completed, performing a second stroke, calculating a second temperature value of a dishware contained in a rack when the second stroke is completed, calculating the emissivity of a dishware contained in a rack based on the first temperature value and the second temperature value, and determining a third stroke based on the emissivity.

Description

Technology Field

[0001] This specification relates to a dishwasher and a customized cleaning method for a dishwasher. Background Technology

[0003] A dishwasher is a device that cleans dishes by removing food residue and grease stains left on dishes after a meal through the spraying of dishwashing water in which detergent is dissolved. Specifically, dishwashing water is sprayed at high pressure inside a tub, and the sprayed water comes into contact with the dishes, thereby cleaning away foreign substances such as food residue stuck to the surface of the dishes.

[0004] The process of a dishwasher washing dishes does not simply end with the spraying of detergent-dissolved water, but is accomplished through several stages.

[0005] The internal structure of the dishwasher and the step-by-step process of the dishwasher are explained below.

[0006] FIG. 1 is a perspective view of a dishwasher, and FIG. 2 shows a perspective view of a conventional dishwasher with the door open.

[0007] Referring to FIG. 1, the exterior of the dishwasher consists of a case (1) that is open at the front and a door (2) that seals the open front of the case. The case (1) and the door (2) at the front of the dishwasher seal the internal space so that washing water or detergent does not leak out while washing dishes.

[0008] Referring to FIG. 2, when the door (2) is opened, the door (2) can be opened at a 90-degree right angle with the case (1). The interior of the dishwasher is configured to include a tub (18) for receiving washing water, a sump (16) at the bottom of the tub for collecting washing water and filtering out foreign matter before spraying, a nozzle (14) connected to the sump that rotates and sprays washing water into the tub, and a rack (11, 12) formed inside the tub and divided into upper and lower sections for storing a plurality of dishes.

[0009] Figure 3 is a flowchart showing the step-by-step operation sequence of a conventional dishwasher.

[0010] The dishwasher can operate in the steps of pre-wash (100), main wash (110), rinse (120), heated rinse (130), and drying (140).

[0011] When a user loads used dishes onto the racks (11, 12) of a dishwasher, food residue may remain on the dishes. Therefore, the dishwasher can perform a pre-wash (100) as the first step. During the pre-wash (100) step, the detergent is not guided toward the lower side of the tub, so large food particles among the food stuck to the dishes are removed first using only wash water without detergent.

[0012] When the dishwasher finishes the pre-wash (100), it performs the main wash (110) process. If the dishwasher performs the main wash (110) of the dishes using only wash water without detergent, the grease stains on the dishes are not washed well, so the dishes are washed by removing grease stains through the main wash using detergent.

[0013] When the main wash (110) is finished, the dishwasher discharges the used wash water to the outside through the sump (16) and supplies new wash water to perform a rinsing (120) cycle. Afterwards, the dishwasher performs a heated rinse (130) cycle using high-temperature heated wash water to rinse the dishes once again and simultaneously raise the temperature of the dish surface so that moisture on the dish surface can easily evaporate in a short time. Finally, the dishwasher performs a drying (140) cycle to dry the dishes and completes all steps necessary for dishwashing.

[0014] Meanwhile, the level of drying and cleaning of tableware varies depending on the material. For example, if the tableware is made of plastic, the thermal conductivity and heat capacity are low, so moisture does not dry well and the drying time must be long; and if the tableware is made of glass, water stains are easily left behind, so an additional rinsing step is required.

[0015] Therefore, in the case of conventional dishwashers, since the same washing routine is performed uniformly without considering these materials, there is a problem in that proper drying and washing suitable for the type of dishes are not performed. The problem to be solved

[0017] The purpose of this specification is to distinguish the material of tableware using an optical sensor and to perform different operations according to the distinguished material of the tableware.

[0018] In addition, the purpose of this specification is to improve the drying and washing performance of tableware by performing customized procedures according to the material of the tableware.

[0019] The purposes of this specification are not limited to those mentioned above, and other purposes and advantages of this specification not mentioned may be understood from the following description and will be more clearly understood by the embodiments of this specification. Furthermore, it will be readily apparent that the purposes and advantages of this specification can be realized by the means and combinations thereof set forth in the claims. means of solving the problem

[0021] A dishwasher according to one embodiment of the present specification comprises: a case forming an exterior and having an open front; a door sealing the open front of the case; a tub containing washing water inside; a rack located inside the tub and containing dishes; an optical sensor positioned on at least one of the inner surface of the door and the inner surface of the tub to photograph the upper surface of the rack; and a control unit that controls the operation of the dishwasher by sequentially performing a process consisting of a plurality of steps. The control unit performs a first process, and when the first process is completed, calculates a first temperature value of the dishes contained in the rack, performs a second process, and when the second process is completed, calculates a second temperature value of the dishes contained in the rack, calculates the emissivity of the dishes contained in the rack based on the first temperature value and the second temperature value, and determines a third process based on the emissivity.

[0022] In one embodiment of the present specification, a first temperature value is calculated from a first thermal image obtained through an optical sensor after the first step is completed, and a second temperature value is calculated from a second thermal image obtained through an optical sensor after the second step is completed.

[0023] In one embodiment of the present specification, the control unit terminates the second stroke and calculates the second temperature value when the temperature inside the tub is greater than or equal to a preset second stroke termination temperature.

[0024] In one embodiment of the present specification, the control unit determines that if the emissivity is less than a first reference value, the third stroke performs a basic stroke.

[0025] In one embodiment of the present specification, the control unit determines that if the emissivity is greater than or equal to a first reference value and less than a second reference value, the third step performs an additional drying step.

[0026] In one embodiment of the present specification, the control unit determines that if the emissivity exceeds a second reference value, the third step performs an additional rinsing step.

[0027] In one embodiment of the present specification, the control unit calculates a first temperature value from a plurality of first thermal images and calculates a second temperature value from a plurality of second thermal images to calculate the emissivity.

[0028] In one embodiment of the present specification, the emissivity is calculated based on the following [Equation 1].

[0029] [Mathematical Formula 1]

[0030]

[0031] Here, ε is the emissivity, P is the total radiated power inside the tub, A is the radiated area, F is the shape factor, σ is the Stefan constant, Ts is the first temperature value, and Tr is the second temperature value.

[0032] A customized washing method for a dishwasher according to one embodiment of the present specification includes the steps of performing a first stroke, calculating a first temperature value of a dishware contained in a rack when the first stroke is completed, performing a second stroke, calculating a second temperature value of a dishware contained in a rack when the second stroke is completed, calculating the emissivity of a dishware contained in a rack based on the first temperature value and the second temperature value, and determining a third stroke based on the emissivity.

[0033] In one embodiment of the present specification, a first temperature value is calculated from a first thermal image obtained through an optical sensor after the first step is completed, and a second temperature value is calculated from a second thermal image obtained through an optical sensor after the second step is completed.

[0034] In one embodiment of the present specification, the step of calculating a second temperature value of a tableware contained in the rack when the second stroke is terminated includes the step of terminating the second stroke and calculating the second temperature value when the temperature inside the tub is greater than or equal to a preset second stroke termination temperature.

[0035] In one embodiment of the present specification, the step of determining a third administration based on emissivity is determined such that if the emissivity is less than a first reference value, the third administration performs a basic administration.

[0036] In one embodiment of the present specification, the step of determining a third process based on emissivity is determined such that if the emissivity is greater than or equal to a first reference value and less than a second reference value, the third process is to perform an additional drying process.

[0037] In one embodiment of the present specification, the step of determining a third step based on emissivity is determined such that if the emissivity exceeds a second reference value, the third step performs an additional rinsing step.

[0038] In one embodiment of the present specification, the step of calculating the emissivity of tableware contained in the rack based on a first temperature value and the second temperature value involves calculating the first temperature value from a plurality of first thermal images and calculating the second temperature value from a plurality of second thermal images to calculate the emissivity.

[0039] In one embodiment of the present specification, the emissivity is calculated based on the following [Equation 1].

[0040] [Mathematical Formula 1]

[0041]

[0042] Here, ε is the emissivity, P is the total radiated power inside the tub, A is the radiated area, F is the shape factor, σ is the Stefan constant, Ts is the first temperature value, and Tr is the second temperature value. Effects of the invention

[0044] A dishwasher according to one embodiment of the present specification can distinguish the material of the tableware using an optical sensor and perform different operations depending on the distinguished material of the tableware.

[0045] In addition, a dishwasher according to one embodiment of the present specification can improve the drying and washing performance of dishes by performing customized processes according to the material of the dishes. Brief explanation of the drawing

[0047] Figure 1 is a perspective view of a dishwasher. FIG. 2 is a perspective view of a conventional dishwasher with the door open. Figure 3 is a flowchart showing the step-by-step sequence of a conventional dishwasher. FIG. 4 is a side cross-sectional view of a dishwasher with an optical sensor attached inside in one embodiment of the present specification. FIG. 5 is a front cross-sectional view of a dishwasher with an optical sensor attached inside in one embodiment of the present specification. FIG. 6 is a configuration diagram of a dishwasher according to one embodiment of the present specification. FIG. 7 is a thermal image captured by an optical sensor in one embodiment of the present specification. FIG. 8 is a table showing the emissivity corresponding to the material of the tableware in one embodiment of the present specification. FIG. 9 is a schematic flowchart of a customized washing method for a dishwasher according to one embodiment of the present specification. FIG. 10 is a flowchart illustrating the sequence of a customized washing method for a dishwasher according to one embodiment of the present specification. Specific details for implementing the invention

[0048] The aforementioned objectives, features, and advantages are described in detail below with reference to the attached drawings, and accordingly, a person skilled in the art to which this specification pertains will be able to easily implement the technical concept of this specification. In describing this specification, detailed descriptions of known technologies related to this specification are omitted if it is determined that such descriptions would unnecessarily obscure the gist of this specification. Hereinafter, preferred embodiments according to this specification will be described in detail with reference to the attached drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

[0049] Hereinafter, a dishwasher according to one embodiment of the present specification will be described with reference to each drawing.

[0050] FIG. 4 is a side cross-sectional view of a dishwasher with an optical sensor attached inside in one embodiment of the present specification, and FIG. 5 is a front cross-sectional view of a dishwasher with an optical sensor attached inside in one embodiment of the present specification.

[0051] Referring to the drawing, the exterior of the dishwasher (3) is formed by a case (1) that is open at the front and a door (2) that seals the open front of the case (1).

[0052] Inside the dishwasher, a tub (18) is placed to receive washing water, and below the tub, a sump (16) is placed to collect washing water, filter out foreign matter, and spray it again.

[0053] Specifically, a plurality of racks (11, 12) separated vertically are formed inside the tub (18), and a nozzle (14) that sprays cleaning water toward each rack (11, 12) is formed. In addition, a cleaning water passage (19) that supplies cleaning water to an upper nozzle (14a) and a top nozzle (14c) is provided on one side inside the tub (18).

[0054] Additionally, in one embodiment of the present specification, an optical sensor may be provided inside the tub (18). The optical sensor may be a thermal imaging camera or a temperature measuring device, but is not limited thereto, and includes any device capable of detecting infrared radiation emitted from an object and measuring the temperature of the object without contact with the object. The following description is limited to the premise that the optical sensor is a thermal imaging camera.

[0055] Referring again to the drawings, a plurality of thermal imaging cameras (210) may be provided inside the tub (18). Specifically, as shown in FIGS. 4 and 5, a thermal imaging camera (210a, 210b, 210e, 210f) for photographing tableware contained in the upper rack (11) may be located at the top of the upper rack (11), and a thermal imaging camera (210c, 210d, 210g, 210h) for photographing tableware contained in the lower rack (12) may be located in the middle section between the lower rack (12) and the upper rack (11).

[0056] Additionally, a thermal imaging camera (210) may be provided on one side of the inside of the tub (18). Specifically, as shown in FIGS. 4 and 5, a groove may be formed on the inner side of the tub, and a thermal imaging camera (210b, 210d, 210e, 210f, 210g, 210h) may be placed inside the formed groove. The formed groove may be treated so that the inner side of the tub is not curved using a shield. The shield may be made of a transparent material, such as glass or plastic, so that the inside of the tub can be photographed from inside the groove.

[0057] As described above, by placing the thermal imaging camera (210) inside the home, the possibility of the camera being damaged or physically broken by the dishwashing operation of the dishwasher can be reduced. Additionally, by removing the curvature of the inner surface of the tub (18) through the cover, the camera can be protected and foreign matter can be prevented from getting stuck in the camera lens.

[0058] In one embodiment of the present specification, a thermal imaging camera (210) may be provided on the inner surface of the door (2). As shown in FIG. 4, a groove may be formed on the inner surface of the door (2) and a thermal imaging camera (210a, 210c) may be placed inside the formed groove. The formed groove may be treated so that the inner surface of the door (2) is not curved by using a cover.

[0059] Accordingly, the dishwasher of the present specification can photograph dishes from various angles by installing a plurality of thermal imaging cameras (210) on the inner surface of the door (2) and the tub (18). Accordingly, the dishwasher (3) can generate various thermal images and, furthermore, can calculate accurate temperature values ​​and emissivity to perform customized operations according to the type of dishes.

[0060] FIG. 6 is a configuration diagram of a dishwasher according to one embodiment of the present specification, FIG. 7 is a thermal image captured by an optical sensor in one embodiment of the present specification, and FIG. 8 is a table showing the emissivity corresponding to the material of the tableware in one embodiment of the present specification.

[0061] Below, the configuration of the dishwasher is described based on FIG. 6 and with reference to FIG. 7 and FIG. 8.

[0062] The control unit (200) controls the dishwasher by performing operations related to washing dishes sequentially according to a preset order. When the thermal imaging camera (210) captures a first thermal image and a second thermal image at different times, the control unit (200) stores the captured first thermal image and second thermal image in the image storage unit (220).

[0063] The control unit (200) can calculate a first temperature value and a second temperature value from the first thermal image and the second thermal image stored through the temperature calculation unit (222), respectively. The thermal image is a thermal image that detects heat by detecting infrared rays emitted from the tableware and visually displays the temperature distribution of the tableware by expressing it in different colors according to the temperature so that it can be visually confirmed.

[0064] Referring to the thermal image in Fig. 7, the tableware in the thermal image is represented in different colors according to temperature in a gradient from low temperature in blue to high temperature in red.

[0065] Meanwhile, the temperature inside the tub gradually rises during the washing process. Therefore, as time passes, the heat generated from the dishes also changes, so the first temperature value and the second temperature value have different values.

[0066] For example, the first thermal image (70) of FIG. 7 is a thermal image generated after 5 minutes have elapsed since the first process began, and the second thermal image (71) is a thermal image generated after the second process ended (after 15 minutes have elapsed since the first process began). As illustrated, since the second thermal image (71) contains more red pixels than the first thermal image (70), the second temperature value calculated from the second thermal image (71) is higher than the first temperature value calculated from the first thermal image (70), i.e., they have different values.

[0067] The control unit (200) can extract a temperature value from the color value of each pixel represented by a different color within the thermal image through the temperature calculation unit (222). The control unit (200) may use a predetermined color model to extract the temperature value from the color value. For example, the color model may be one of RGB, CMYK, HSV, HSL, or HEX. However, it is not limited thereto and includes all color models used as a method of representing color in digital.

[0068] The color value may be a pre-set value assigned to each color used in a predetermined color model. Specifically, the control unit (200) may pre-set a temperature value corresponding to each color value through the temperature calculation unit (222), and may calculate a temperature value for each pixel corresponding to the color value of each pixel for each pixel in the thermal image. Here, the first temperature value may be the average value of the temperature values ​​of each pixel in the tableware area in the first thermal image, and the second temperature value may be the average value of the temperature values ​​of each pixel in the tableware area in the second thermal image.

[0069] Meanwhile, the first thermal image and the second thermal image may be multiple. In one embodiment of the present specification, the control unit (200) extracts a first temperature value from each of the multiple first thermal images through the temperature calculation unit (222), and if all of the extracted first temperature values ​​do not match, the temperature value extracted most frequently as the first temperature value may be selected as the first temperature value. Similarly, the control unit (200) extracts a second temperature value from each of the multiple second thermal images through the temperature calculation unit (222), and if all of the extracted second temperature values ​​do not match, the temperature value extracted most frequently as the second temperature value may be selected as the second temperature value.

[0070] In another embodiment of the present specification, the control unit (200) extracts a first temperature value from each of a plurality of first thermal images through the temperature calculation unit (222), and if all of the extracted first temperature values ​​do not match, the average value of the extracted first temperature values ​​can be selected as the first temperature value. Similarly, the control unit (200) extracts a second temperature value from each of a plurality of second thermal images through the temperature calculation unit (222), and if all of the extracted second temperature values ​​do not match, the average value of the extracted second temperature values ​​can be selected as the second temperature value.

[0071] The control unit (200) can calculate an accurate temperature value by extracting a first temperature value and a second temperature value from a plurality of first thermal images and a plurality of second thermal images, and through this, can calculate an accurate emissivity and perform customized administration according to the type of tableware.

[0072] The control unit (200) can calculate the emissivity, which is the ratio of energy radiated from the surface of a material during thermal radiation, based on the first temperature value and the second temperature value calculated through the emissivity calculation unit (224). The control unit (200) can calculate the emissivity using the Stefan-Boltzmann law, which is [Equation 1] below.

[0073] [Mathematical Formula 1]

[0074]

[0075] Here, ε is the emissivity, P is the net radiated power inside the tub, A is the radiating area, F is the view factor, and σ is Stefan's constant; ), Ts is the first temperature value (absolute temperature K; Kelvin temperature), and Tr is the second temperature value (absolute temperature K; Kelvin temperature).

[0076] P, A, and σ are constants and fixed values, and the variables are Ts, Tr, and ε. Therefore, if only the variables Ts (first temperature value) and Tr (second temperature value) are obtained, ε (emissivity) can be calculated through the above [Equation 1].

[0077] Meanwhile, emissivity has a value between 0 and 1. Emissivity can have different values ​​depending on the type and material of the tableware, as determined by experiments. For example, the tableware materials listed in Fig. 8 have values ​​of 0.92 for glass, 0.90 for wood, 0.84 for plastic, 0.59 for stainless steel, and 0.34 for stainless steel plate.

[0078] However, the tableware contained in the rack (11, 12) may not be made of only one material, but may be made of a mixture of two or more materials. In this case, the total emissivity may vary depending on the emissivity of each material of the tableware contained and the amount of tableware contained.

[0079] However, according to the present specification, even when tableware of two or more materials is mixed and accommodated in a rack, if only the first temperature value and the second temperature value are obtained, the control unit (200) can calculate the emissivity of the tableware through the emissivity calculation unit (224) and determine what type of tableware is accommodated in the rack (11, 12) or what material of tableware is predominantly accommodated. Accordingly, the control unit (200) can perform a third action according to the determined type of tableware.

[0080] The control unit (200) can determine the third administration through the third administration determination unit (226). The third administration may include a basic administration (S66-a), an additional drying administration (S66-b), and an additional rinsing administration (S66-c), and the third administration determination unit (226) can select one of the administrations to determine the administration to be performed in the next step.

[0081] When the third stroke is determined to be an additional drying stroke (S66-b), the control unit (200) performs an additional drying stroke through the drying device (212), and when the third stroke is determined to be an additional rinsing stroke (S66-c), it controls the washing motor (17) located at the bottom of the tub (18) and performs an additional rinsing stroke by spraying washing water into the tub through the lower nozzle (14b) connected to the sump (16) and the upper nozzle (14a) and top nozzle (14c) connected to the washing water passage (19). Detailed determination criteria and operation details for the third stroke will be described later.

[0082] FIG. 9 is a schematic flowchart of a customized washing method for a dishwasher according to one embodiment of the present specification.

[0083] The control unit (200) can first perform the first operation, which is the first operation among the several stages of the dishwasher, when power is applied according to the user's operation and a washing operation input is received (S590). The first operation may be a pre-wash operation that washes large food items remaining on the dishes without detergent.

[0084] The first operation is performed for a predetermined period of time, and when the first operation is completed, the thermal imaging camera (210) captures the upper part of the rack (11, 12) containing the tableware to generate a first thermal image. The control unit (200) stores the generated first thermal image in the image storage unit (220), and the temperature calculation unit (222) calculates a first temperature value based on the first thermal image (S610).

[0085] Afterward, the control unit (200) performs the next step, the second step (S620). The second step may be a main washing step in which the dishes are washed using high-temperature washing water along with detergent.

[0086] When the second administration is completed, the thermal imaging camera (210) captures the upper part of the rack (11, 12) containing the tableware to generate a second thermal image. The control unit (200) stores the generated second thermal image in the image storage unit (220), and the control unit (200) calculates a second temperature value from the second thermal image through the temperature calculation unit (222) (S640).

[0087] The control unit (200) calculates the emissivity using the following [Equation 1] based on the first temperature value and the second temperature value calculated through the emissivity calculation unit (224) (S650).

[0088] [Mathematical Formula 1]

[0089]

[0090] Here, ε is the emissivity, P is the net radiated power inside the tub, A is the radiating area, F is the view factor, and σ is Stefan's constant; ), Ts is the first temperature value (absolute temperature K; Kelvin temperature), and Tr is the second temperature value (absolute temperature K; Kelvin temperature).

[0091] Subsequently, the control unit (200) can determine a third stroke based on the emissivity calculated through the third stroke determination unit (226) (S66). The dishwasher performs different strokes according to the determined third stroke. According to the present specification, since different customized strokes are performed according to the type of dishwasher through the calculation of the emissivity of the dishwasher, the drying and washing performance of the dishwasher is improved.

[0092] FIG. 10 is a flowchart illustrating the sequence of a customized washing method for a dishwasher according to one embodiment of the present specification.

[0093] As described above, when the first operation, which operates for a predetermined time, is completed (S60), the thermal imaging camera (210) captures the upper part of the rack (11, 12) containing the tableware to generate a first thermal image. The control unit (200) stores the generated first thermal image in the image storage unit (220), and the temperature calculation unit (222) calculates a first temperature value based on the first thermal image (S61).

[0094] Afterward, the control unit (200) performs the next step, the second step (S62). The second step may be a main washing step in which the dishes are washed using high-temperature washing water along with detergent. As high-temperature washing water is used, the temperature inside the tub may rise over time.

[0095] The control unit (200) can pre-set the second stroke end temperature in the second stroke. As the temperature inside the tub rises, if the temperature inside the tub becomes equal to the second stroke end temperature, the control unit (200) can terminate the second stroke operation (S63). For example, if the second stroke end temperature is 50*, and the temperature inside the tub is equal to or higher than 50*, the control unit (200) can terminate the second stroke.

[0096] When the second administration is completed, the thermal imaging camera (210) captures the upper part of the rack (11, 12) containing the tableware to generate a second thermal image. The control unit (200) stores the generated second thermal image in the image storage unit (220), and the control unit (200) calculates a second temperature value from the second thermal image through the temperature calculation unit (222) (S64).

[0097] The control unit (200) calculates the emissivity through the [Equation 1] based on the first temperature value and the second temperature value calculated through the emissivity calculation unit (224) (S65).

[0098] At this time, even when tableware of two or more materials is mixed and accommodated in the rack, if only the first temperature value and the second temperature value are obtained, the control unit (200) can calculate the emissivity of the tableware through the emissivity calculation unit (224) and determine what type of tableware is accommodated in the rack (11, 12) or what material of tableware is predominantly stored. Accordingly, the control unit (200) can perform a third action according to the determined type of tableware.

[0099] The control unit (200) can determine a third stroke based on the emissivity calculated through the third stroke determination unit (226) (S66). Specifically, the control unit (200) can pre-set a first reference value and a second reference value. The first reference value and the second reference value are values ​​set to determine different strokes according to the calculated emissivity, and can be set to values ​​between 0 and 1.

[0100] More specifically, the control unit (200) may determine that if the calculated emissivity is less than the first reference value, the third process performs a basic process (S66-a); if the calculated emissivity is greater than or equal to the first reference value and less than the second reference value, the third process performs an additional drying process (S66-b); and if the calculated emissivity exceeds the second reference value, the third process performs an additional rinsing process (S66-c).

[0101] For example, if the first reference value is set to 0.7 and the second reference value is set to 0.9, the control unit (200) may decide to perform a basic process when tableware made of stainless steel with an emissivity of 0.59 is received in the rack (11, 12), decide to perform an additional drying process when tableware made of plastic with an emissivity of 0.84 is received in the rack (11, 12), and decide to perform an additional rinsing process when tableware made of glass with an emissivity of 0.92 is received in the rack (11, 12).

[0102] Here, the basic process (S66-a) may be a rinsing process as the next step of the process that is sequentially performed by the control unit (200). When the basic process is determined, the control unit (200) controls the washing motor (17) located at the bottom of the tub (18) to perform a rinsing operation by spraying washing water into the tub through the nozzle (14) connected to the sump (16).

[0103] The additional drying step (S66-b) is a step for performing an additional drying step. When the additional drying step (S66-b) is determined, the control unit (200) extends the execution time of the drying step among the steps of the sequence that are pre-set. Thus, it can help dry dishes that are not completely dried.

[0104] The additional rinsing operation (S66-c) is an operation that performs an additional rinsing action. When the additional rinsing operation (S66-c) is determined, the control unit (200) performs an additional rinsing action immediately after the rinsing operation is completed. Thus, it can help rinse dishes that have not been completely rinsed.

[0105] As described above, the drying and washing levels of the dishes placed in the rack vary depending on the material of the dishes. For example, if the dish material is plastic, the thermal conductivity and heat capacity are low, so moisture does not dry well and the drying time must be long; and if the dish material is glass, water stains are easily left, so an additional rinsing action must be included.

[0106] According to the present specification, the drying and washing performance of a dishwasher is improved because different customized processes are performed according to the type of tableware through the calculation of the emissivity of the tableware.

[0107] Although the present invention has been described above with reference to the illustrated drawings, the present invention is not limited by the embodiments and drawings disclosed in this specification, and it is obvious that various modifications can be made by a person skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention were not explicitly described while explaining the embodiments of the present invention above, it is natural to acknowledge that the effects predictable by said configuration should also be recognized.

Claims

Claim 1 A dishwasher comprising: a case forming an exterior and having an open front; a door sealing the open front of the case; a tub containing washing water; a rack located inside the tub and containing dishes; an optical sensor positioned on at least one of the inner surface of the door and the inner surface of the tub to photograph the upper surface of the rack; and a control unit that controls the operation of the dishwasher by sequentially performing a process consisting of a plurality of steps, wherein the control unit performs a first process, calculates a first temperature value of the dishes contained in the rack when the first process is completed, performs a second process, calculates a second temperature value of the dishes contained in the rack when the second process is completed, calculates the emissivity of the dishes contained in the rack based on the first temperature value and the second temperature value, and determines a third process based on the emissivity. Claim 2 In claim 1, the first temperature value is calculated from a first thermal image obtained through an optical sensor after the first stroke is completed, and the second temperature value is calculated from a second thermal image obtained through an optical sensor after the second stroke is completed. Claim 3 A dishwasher according to claim 1, wherein the control unit terminates the second stroke and calculates the second temperature value when the temperature inside the tub is greater than or equal to a preset second stroke termination temperature. Claim 4 A dishwasher according to claim 1, wherein the control unit determines that if the emissivity is less than the first reference value, the third stroke performs the basic stroke. Claim 5 A dishwasher according to claim 1, wherein the control unit determines that if the emissivity is greater than or equal to a first reference value and less than a second reference value, the third step performs an additional drying step. Claim 6 A dishwasher according to claim 1, wherein the control unit determines that if the emissivity exceeds a second reference value, the third stroke performs an additional rinsing stroke. Claim 7 A dishwasher according to claim 1, wherein the control unit calculates a first temperature value from a plurality of first thermal images and calculates a second temperature value from a plurality of second thermal images to calculate the emissivity. Claim 8 In claim 1, the above-mentioned emissivity is a dishwasher calculated based on the following [Mathematical Formula 1]. [Mathematical Formula 1] Here, ε is the emissivity, P is the total radiated power inside the tub, A is the radiated area, F is the form factor, σ is the Stefan constant, Ts is the first temperature value, and Tr is the second temperature value Claim 9 A customized cleaning method for a dishwasher comprising: a step of performing a first operation; a step of calculating a first temperature value of a dishware contained in a rack when the first operation is completed; a step of performing a second operation; a step of calculating a second temperature value of a dishware contained in a rack when the second operation is completed; a step of calculating the emissivity of a dishware contained in a rack based on the first temperature value and the second temperature value; and a step of determining a third operation based on the emissivity. Claim 10 A customized cleaning method for a dishwasher according to claim 9, wherein the first temperature value is calculated from a first thermal image obtained through an optical sensor after the first stroke is completed, and the second temperature value is calculated from a second thermal image obtained through an optical sensor after the second stroke is completed. Claim 11 In claim 9, the step of calculating a second temperature value of a dishwasher contained in the rack when the second stroke is terminated comprises the step of terminating the second stroke and calculating the second temperature value when the temperature inside the tub is greater than or equal to a preset second stroke termination temperature. Claim 12 In claim 9, the step of determining the third stroke based on the above-mentioned emissivity determines that if the above-mentioned emissivity is less than the first reference value, the third stroke performs the basic stroke, in a customized cleaning method for a dishwasher. Claim 13 In claim 9, the step of determining the third step based on the above emissivity determines that if the above emissivity is greater than or equal to a first reference value and less than a second reference value, the third step performs an additional drying step, in a customized cleaning method for a dishwasher. Claim 14 In claim 9, the step of determining the third step based on the above emissivity determines that if the above emissivity exceeds a second reference value, the third step performs an additional rinsing step, in a customized washing method for a dishwasher. Claim 15 In claim 9, the step of calculating the emissivity of tableware contained in the rack based on the first temperature value and the second temperature value is a customized cleaning method for a dishwasher that calculates the emissivity by calculating the first temperature value from a plurality of first thermal images and calculating the second temperature value from a plurality of second thermal images. Claim 16 In claim 9, the above-mentioned emissivity is a customized cleaning method for a dishwasher calculated based on the following [Equation 1]. [Equation 1] Here, ε is the emissivity, P is the total radiated power inside the tub, A is the radiated area, F is the form factor, σ is the Stefan constant, Ts is the first temperature value, and Tr is the second temperature value

Images