Washing apparatus with induction heater

Abstract

This invention relates to a washing apparatus that uses an induction heater to heat a drum and its control method. The washing apparatus includes: an outer tub; a drum rotatably disposed within the outer tub to hold an object; an induction heater disposed in the outer tub to heat the outer peripheral surface of the drum opposite to the induction heater; a motor to rotate the drum; a power supply device to supply power to the washing apparatus from an external power source; a relay to open and close the current applied to the induction heater via a wire from the power supply device, the relay being normally open; a processor connected to the relay via a control line to control the relay's drive, and to control the drive of the induction heater and the motor; and a first safety device disposed on the control line to open and close the control signal applied from the processor to the relay, operating according to temperature changes.

Description

[0001] This application is a divisional application of patent application No. CN 202010024757.X, filed on January 10, 2020, with the title of "Washing Device with Induction Heater". TECHNICAL FIELD

[0002] The present application relates to a washing device, and more particularly, to a washing device heating a drum using an induction heater and a control method thereof. BACKGROUND

[0003] The washing device includes an outer tub (outer drum) storing washing water and a drum (inner drum) rotatably disposed inside the outer tub. The drum is loaded with washing objects (laundry), and the laundry is washed using a detergent and washing water as the drum rotates.

[0004] In order to increase washing efficiency by promoting activation of the detergent and decomposition of contaminants, washing water at a high temperature is supplied to the inside of the outer tub or heated therein. To this end, a heater installation portion is formed by being recessed downward at a lower portion inside the outer tub, and a heater is disposed in the heater installation portion. Such a heater is typically a sheath heater.

[0005] The washing device can include a washer-dryer capable of performing washing and drying and a dryer capable of only performing drying.

[0006] Generally, drying can be performed by supplying hot air at a high temperature to the inside of the drum to heat the objects to evaporate moisture. Exhaust-type dryers that exhaust moist air to the outside of the washing device and circulation-type dryers that condense moisture in the moist air to supply it to the drum again can be included.

[0007] Drying is a process of heating objects to remove moisture, and thus, it is very important to accurately determine an end time point of drying. That is, it is very important to stop heating the objects and end drying when the moisture content of the objects reaches a preset moisture content. Thereby, under-drying or over-drying can be prevented.

[0008] In many cases, a humidity sensor is used to detect the degree of drying or humidity. That is, the moisture content or humidity of the objects is detected by a sensor such as an electrode rod exposed to the inside of the drum. Thus, when the appropriate humidity is detected by the humidity sensor, drying is ended.

[0009] However, such a humidity sensor is suitable for a dryer that performs drying by supplying hot air. This is because, in a washer-dryer capable of performing washing, the humidity sensor is likely to be contaminated by a detergent, washing water, or lint, etc. Such contamination causes difficulty in sensing accurate humidity. Thus, generally, such a humidity sensor is applied to a dryer that performs only drying.

[0010] Also, a prior art has been disclosed in which, in a washer-dryer having a condensing duct and a drying duct as a part of a circulation duct of circulating hot air, temperature sensors are installed near an inlet end (an inlet through which air flows from the outer tub to the condensing duct) of the condensing duct and near an outlet end (an outlet through which air is discharged from the condensing duct to the drying duct) of the condensing duct, respectively, to determine a drying end time point. As an example, in Korean Patent Publication No. KR10-2015-0134069, a drying degree is determined by a difference between a temperature of condensed water and a temperature of air after condensation. Since moisture condensation occurring in a late drying stage is very small, a drying degree can be indirectly determined using a temperature decrease of the condensed water to a temperature close to that of cooling water (water at room temperature).

[0011] However, the drying degree detection of this method is premised on the circulation of air, and requires a separate circulation duct (including a condensing duct performing condensation and a drying duct performing heating of air). In addition, two temperature sensors need to be installed at the front end and the rear end of the condensing duct, and thus it is not easy to manufacture. In particular, a temperature sensor for detecting a temperature of washing water is additionally required, and thus there is a problem in that more than three temperature sensors are required to detect the temperature of the washing water and the drying degree.

[0012] The present applicant has disclosed a washing device using an induction heater through a Korean Patent Application No. 10-2017-0101333 (hereinafter referred to as "prior application").

[0013] In the prior application, a washing device that heats and dries an object by directly heating a drum with an induction heater is disclosed. In addition, a washing device that supplies cooling water to an inner circumferential surface of an outer tub to condense moisture from humid air inside the outer tub is disclosed.

[0014] The washing device disclosed in the prior application can not be provided with a circulation duct, and can be configured to perform washing and drying. Thus, it is necessary to find a solution that can grasp an end time point of drying by effectively detecting a drying degree or humidity in a washing device of this form.

[0015] In addition, in the prior application, specific details for controlling driving of a heating source, i.e., an induction heater, are not disclosed. In particular, a problem that the washing device can be protected when unexpected overheating occurs is not disclosed.

[0016] The induction heater can heat the drum to a very high temperature, and thus, a scheme capable of not only controlling (actively controlling) the driving of the induction heater in a normal state but also forcibly stopping the induction heater in an abnormal state can be required. In particular, a scheme capable of preventing a safety accident caused by the induction heater in advance even in a case where an unexpected malfunction or error of a structure such as a sensor or a relay occurs is required. SUMMARY

[0017] An object of the present application is to provide a washing device and a control method thereof, which can effectively grasp an end time point of drying in a washing device in which a circulation duct is not provided.

[0018] An object of the present application is to provide a washing device and a control method thereof, which can significantly reduce an error operation or error detection of a sensor for detecting a drying degree due to a detergent, washing water, condensed water, cooling water, or lint, by an embodiment of the present application.

[0019] An object of the present application is to provide a washing device and a control method thereof, which can detect a drying degree using a washing water temperature sensor provided in an existing washing device, by an embodiment of the present application. That is, an object is to provide a washing device and a control method thereof, which can use one temperature sensor for other purposes according to a program performed by the washing device.

[0020] An object of the present application is to provide a washing device and a control method thereof, which can minimize a temperature deviation due to cooling water by preventing the cooling water and condensed water from being in contact with a washing water temperature sensor during drying, thereby being able to accurately judge a drying degree, by an embodiment of the present application.

[0021] An object of the present application is to provide a washing device and a control method thereof, which can detect a drying degree using a drying temperature sensor provided to prevent overheating of an induction heater, by an embodiment of the present application. That is, an object is to provide a washing device and a control method thereof, which can use one temperature sensor for multiple purposes.

[0022] An object of the present application is to provide a washing device and a control method thereof, which can effectively judge an end time point of drying without directly contacting a drying object with a sensor, by an embodiment of the present application.

[0023] An object of the present application is to provide a washing device and a control method thereof capable of effectively determining a drying load and a drying end time point by one or two temperature sensors. In particular, an object of the present application is to provide a washing device and a control method thereof capable of effectively determining a drying load and a drying end time point based on a temperature change around condensate water condensed by natural convection of moisture during drying.

[0024] An object of the present application is to provide a washing device in which a processor can actively control driving of an induction heater through a temperature sensor in a normal state, and can forcibly stop driving of the induction heater to secure safety even in an abnormal state.

[0025] An object of the present application is to provide a washing device in which a processor can actively control driving of an induction heater through a temperature sensor in a normal state, and can forcibly stop driving of the induction heater to secure safety even in an abnormal state.

[0026] An object of the present application is to provide a washing device in which a processor can actively control driving of an induction heater through a temperature sensor in a normal state, and can forcibly stop driving of the induction heater to secure safety even in an abnormal state.

[0027] An object of the present application is to provide a washing device in which a processor can actively control driving of an induction heater through a temperature sensor in a normal state, and can forcibly stop driving of the induction heater to secure safety even in an abnormal state.

[0028] An object of the present application is to provide a washing device in which a processor can actively control driving of an induction heater through a temperature sensor in a normal state, and can forcibly stop driving of the induction heater to secure safety even in an abnormal state.

[0029] To achieve the foregoing object, according to an embodiment of the present application, there can be provided a washing apparatus, characterized by comprising: an outer tub; a drum rotatably disposed in the outer tub to accommodate an object; an induction heater disposed in the outer tub to heat an outer circumferential surface of the drum opposite to the induction heater; a motor to rotate the drum; a power supply device to supply power from an external power source to an inside of the washing apparatus; a relay to open and close a current applied to the induction heater from the power supply device through a wire, the relay being of a normal open type; a processor connected to the relay through a control line to control driving of the relay, and to control driving of the induction heater and driving of the motor; and a first safety device disposed in the control line to open and close a control signal applied to the relay from the processor, to operate according to a temperature change.

[0030] The first safety device is connected to the control line through which a low current flows, rather than the wire through which a relatively high current flows, whereby the reliability of the first safety device can be improved, and the manufacturing cost can be significantly reduced.

[0031] Also, the relay is of a normal open type, whereby the reliability of driving of the relay can be further improved.

[0032] The first safety device can include a thermistor that operates to be disconnected at a preset temperature or higher.

[0033] The first safety device is disposed in the vicinity of a coil of the induction heater, and can operate to be disconnected when the induction heater is overheated. That is, when the induction heater itself is abnormally overheated, driving of the induction heater can be forcibly stopped by the first safety device.

[0034] The first safety device is mounted to the outer tub, and can operate to be disconnected when the drum is overheated. That is, when the outer tub of the drum is abnormally overheated due to driving of the induction heater, driving of the induction heater can be forcibly stopped by the first safety device.

[0035] Of course, here, the temperature preset for the first safety device to operate is preferably higher than a normal driving condition of the washing apparatus and lower than a condition in which a safety accident can occur.

[0036] The first safety device can include a plurality of opening and closing elements connected in series to each other. Thus, when only one of the plurality of opening and closing elements normally operates and is overheated, driving of the induction heater can be forcibly stopped. Thereby, the reliability of the safety system can be further improved.

[0037] The installation positions of the plurality of opening and closing elements are preferably different. Thus, even if one of the opening and closing elements is affected by an unexpected change in the surrounding environment, the other opening and closing elements can operate normally.

[0038] The preset temperatures of the operations of the plurality of opening and closing elements can be set to be different.

[0039] Any one of the plurality of opening and closing elements can be a thermitat, and the other can be a thermal fuse. Reliability can be further improved by using different kinds of opening and closing elements.

[0040] The processor can include a second processor that controls the output of the induction heater, and a first processor that controls the driving of the relay, the motor, and the second processor, the first processor being provided independently of the second processor.

[0041] The first processor can control the relay according to the control logic of the washing device to control a prerequisite for driving the induction heater by zone or time variable. The first processor allows such a prerequisite, and can directly control (start / stop and / or change the output control) the driving of the induction heater through the second processor.

[0042] The washing device according to an embodiment of the present application can include a motor driving device to which the first processor is mounted, the motor driving device being connected in series to the power supply device and supplying current to the motor, and a heater driving device to which the second processor is mounted, the heater driving device being connected to the power supply device in parallel to the motor driving device and supplying current to the induction heater. Such a motor driving device or circuit and the heater driving device or circuit can be provided on different PCBs, or can be provided on one PCB in a manner separated from each other.

[0043] The motor driving device and the heater driving device are connected using a control line between the first processor and the second processor, and preferably exclude a wire connecting the motor driving device and the heater driving device.

[0044] The washing device according to an embodiment of the present application can include a heater power supply device that connects the power supply device and the heater driving device through a wire between the power supply device and the heater driving device.

[0045] The motor driving device and the heater power supply device are connected using a control line between the first processor and the relay, and preferably exclude an electric wire connecting between the motor driving device and the heater power supply device.

[0046] A second safety device is preferably provided in an electric wire connecting the power supply device and the heater driving device, and the second safety device operates according to temperature change to cut off the transmitted current. That is, the second safety device can be provided in a different electric wire or control line from the first safety device, whereby the driving of the induction heater can be forcibly stopped when overheating occurs, regardless of whether a malfunction or misoperation of the first safety device or a malfunction or misoperation of the relay occurs. In particular, when a malfunction or misoperation of any one of the structures such as misoperation of the relay structure occurs, misoperation of the induction heater can be prevented in advance.

[0047] The electric wire connecting the power supply device and the heater driving device can include a first electric wire transmitting an AC power supplied from the power supply device to the heater driving device, and a second electric wire converting an AC power supplied from the power supply device into a low-voltage DC power and transmitting to the second processor. Here, the second safety device is preferably provided in the first electric wire. Accordingly, the driving of the induction heater can be directly and immediately forcibly stopped.

[0048] The second safety device is preferably a thermal fuse. Such a thermal fuse is preferably provided independently of the power supply device and the heater driving device. That is, the thermal fuse is preferably installed at a position other than each PCB.

[0049] In the present embodiment, a thermistor sensing an air temperature inside the outer tub is included, and the processor preferably actively controls the driving of the induction heater based on the temperature detected by the thermistor. That is, in a normal state, the processor preferably performs active control based on the temperature detected by the thermistor. In addition, when an abnormality such as a malfunction or misoperation of the thermistor occurs, the driving of the induction heater is preferably forcibly stopped by the aforementioned safety device.

[0050] The thermistor can include an upper temperature sensor provided at an upper portion of the outer tub and in the vicinity of the induction heater, detecting a temperature of air of a space between the outer tub and the drum, and a lower temperature sensor provided at a lower portion of the outer tub, detecting a temperature of washing water stored in the outer tub or a temperature in the vicinity of the condensate water.

[0051] The processor can control so that a control signal is not actively transmitted to the relay to stop the driving of the induction heater when the thermistor detects a temperature above a preset temperature.

[0052] According to an embodiment of the present invention, the washing device preferably includes a second safety device disposed independently of the first safety device, which is a wire between the power supply device and the induction heater that operates to disconnect the current according to temperature changes.

[0053] To achieve the aforementioned objectives, according to an embodiment of the present invention, a washing apparatus and a control method thereof can be provided. The washing apparatus includes: an outer tub; a drum rotatably disposed within the outer tub to accommodate an object; an induction heater disposed within the outer tub to heat the outer peripheral surface of the drum opposite to the induction heater; a motor driving the motor to rotate the drum; an upper temperature sensor (drying temperature sensor) detecting the temperature around the space between the outer tub and the drum at the upper part of the outer tub; a lower temperature sensor (washing water / condensate water temperature sensor) detecting the temperature around the condensate water flowing into the lower part of the outer tub from which wet vapor evaporated through heat exchange between the heated drum and the object condenses inside the outer tub; and a processor controlling the rotation drive of the drum and the drive of the induction heater to heat the object by heating the drum, thereby performing drying.

[0054] The processor can determine the drying end time by measuring the temperatures detected by the upper and lower temperature sensors. Specifically, the processor can determine the drying end time based on the difference (ΔT) between the temperatures detected by the upper and lower temperature sensors.

[0055] This temperature difference can be achieved by utilizing the following characteristics: inside the outer barrel, heat exchange occurs between the wet steam and the cooling water due to natural convection, and the condensate flows downwards and accumulates.

[0056] The induction heater is preferably located on the outer side of the upper outer circumference of the outer barrel, and the upper temperature sensor is preferably located near the induction heater.

[0057] The upper temperature sensor is preferably located at a position away from the projection surface of the induction heater toward the drum. The upper temperature sensor is preferably installed in a location that senses temperature as close as possible to the heating source while avoiding the influence of the magnetic field generated by the induction heater.

[0058] When viewed from the front, the upper temperature sensor can be located on the upper right side of the outer tub. When viewed from the front, a communication port for air exchange between the outer tub's interior and exterior can be provided on the upper left side of the outer tub. Therefore, the influence of the communication port can be minimized.

[0059] A washing apparatus according to an embodiment of the present invention may include a cooling water port that supplies cooling water to the inner wall of the outer tub from behind the outer tub.

[0060] When viewed from the front, the cooling water port can be configured to supply cooling water from the right side of the outer tub, causing the cooling water to flow along the right inner circumferential surface of the outer tub, and / or to supply cooling water from the left side of the outer tub, causing the cooling water to flow along the left inner circumferential surface of the outer tub. Therefore, the cooling water can be distributed thinly and evenly along the inner circumferential surface of the outer tub, maximizing the heat exchange area between the cooling water and the humid air.

[0061] When a preset temperature is detected by the upper temperature sensor, the processor can control the drive of the induction heater to stop or reduce its output. That is, the upper temperature sensor can be configured to essentially cause the induction heater to perform heating until the target heating temperature is reached, and to repeat the heating process to maintain the target heating temperature.

[0062] Compared to the lower temperature sensor, the upper temperature sensor is preferably located further forward of the outer tub. That is, the upper temperature sensor can be located closer to the heating source. Therefore, the upper temperature sensor can be located further forward of the outer tub than the lower temperature sensor.

[0063] A condensate reservoir can be formed inside the lower part of the outer barrel, which is recessed downwards to collect condensate.

[0064] The lower temperature sensor is preferably disposed on the condensate reservoir, spaced upwards from the bottom of the condensate reservoir. This allows the lower temperature sensor to sense the air temperature surrounding the condensate, rather than directly sensing the temperature of the condensate. That is, the lower temperature sensor can be configured to sense the air temperature (not the water temperature) during drying and the water temperature during washing.

[0065] The lower temperature sensor is preferably installed through the rear wall of the outer barrel.

[0066] For this reason, the condensate reservoir can be formed at the rear of the outer tub, and the outer tub can be configured to slope from front to rear, i.e., a sloping outer tub.

[0067] The lower temperature sensor can be positioned 10mm to 15mm away from the bottom surface of the condensate container, preferably 12mm away. This is to ensure that the lower temperature sensor is installed close to the condensate but does not come into contact with it during drying.

[0068] During the washing process, when the washing device heats the washing water by driving the induction heater, the processor can control the driving of the induction heater to stop or reduce the output when the temperature of the washing water is detected by the lower temperature sensor to reach a preset temperature.

[0069] In other words, the lower temperature sensor can be used to control the target heating temperature of the wash water during washing. The induction heater is driven until the wash water is heated to the target heating temperature, and then the start / stop control of the induction heater can be repeated to maintain the target heating temperature.

[0070] Therefore, in this embodiment, in addition to their respective main functions, the upper temperature sensor and the lower temperature sensor may also have the additional function of determining the drying end time.

[0071] The larger the drying load, the greater the temperature difference used to determine the drying end time point. Therefore, when determining the drying load, the temperature or ΔT at the drying end time point is preset accordingly. The drying load is determined during the drying process, and a drying end factor is determined based on the determined drying load. If the drying end factor is met during the drying process, the drying process ends.

[0072] The processor can determine the drying load by detecting the point in the initial stage of drying where the difference (ΔT) between the temperatures detected by the upper temperature sensor and the lower temperature sensor is at its minimum. This may be based on the fact that the larger the drying load, the later the point at which ΔT is detected to be at its minimum.

[0073] The processor can determine the drying load by detecting the minimum value of the temperature difference (ΔT) between the temperature detected by the upper temperature sensor and the temperature detected by the lower temperature sensor during the initial stage of drying. This may be based on the fact that the minimum value of ΔT relatively increases as the drying load increases.

[0074] The initial drying phase can be defined as the time from the start of drying until ΔT reaches its maximum or the time when the upper temperature sensor initially senses the target heating temperature.

[0075] Therefore, the time point for determining the drying load is preferably after the time point when the upper temperature sensor detects the target heating temperature of the drum.

[0076] The upper and lower temperature sensors are preferably configured as thermistors that perform active control of the processor.

[0077] To achieve the aforementioned objectives, according to an embodiment of the present invention, a washing apparatus and a control method thereof can be provided. The washing apparatus is characterized by comprising: an outer tub; a drum rotatably disposed within the outer tub to accommodate an object; an induction heater disposed within the outer tub to heat the outer peripheral surface of the drum opposite to the induction heater; a motor to rotate the drum; an upper temperature sensor (drying temperature sensor) detecting the temperature around the space between the outer tub and the drum at the upper part of the outer tub; a lower temperature sensor (washing water / condensate water temperature sensor) detecting the temperature around the condensate water flowing into the lower part of the outer tub from the condensation of wet vapor evaporated by heat exchange between the heated drum and the object within the outer tub; and a processor controlling the rotation drive of the drum and the drive of the induction heater to perform drying by heating the object through the drum. After the upper temperature sensor detects a target heating temperature of the drum, the processor determines the drying end time based on the difference (ΔT) between the highest temperature detected by the lower temperature sensor and the temperature subsequently detected by the lower temperature sensor.

[0078] To achieve the aforementioned objective, according to an embodiment of the present invention, a control method for a washing apparatus can be provided, the washing apparatus comprising: an outer tub; a drum rotatably disposed within the outer tub to accommodate an object; and an induction heater disposed within the outer tub to heat the outer peripheral surface of the drum opposite to the induction heater to perform drying. The control method for the washing apparatus is characterized by comprising: a heating step, wherein the induction heater is driven by detecting the temperature around the space between the outer tub and the drum at the upper part of the outer tub using an upper temperature sensor; a condensation step, wherein the temperature of condensate flowing into the lower part of the outer tub due to natural convection in the lower part of the outer tub using a lower temperature sensor; and an ending step, wherein the drying time point is determined by the difference between the temperature detected by the upper temperature sensor and the temperature detected by the lower temperature sensor, or the difference between the highest temperature detected by the lower temperature sensor and the subsequent temperature detected by the lower temperature sensor, to end the drying process.

[0079] During the drying process, the heating step and the condensation step can be performed in parallel.

[0080] To achieve the aforementioned objective, according to an embodiment of the present invention, a washing apparatus can be provided, characterized in that it comprises: an outer tub; a drum rotatably disposed within the outer tub to accommodate an object; an induction heater disposed in the outer tub to heat the outer peripheral surface of the drum opposite to the induction heater; a first temperature sensor for detecting the temperature of air in the space between the outer tub and the drum; a second temperature sensor for detecting the temperature of washing water in the outer tub or the temperature near condensate in the outer tub; and a processor for controlling the drive of the induction heater to heat the drum to heat and dry the object based on the temperature detected by at least one temperature sensor, wherein when the temperature detected by the first temperature sensor is greater than or equal to a first temperature, the processor controls the drive of the induction heater to stop or reduce the output of the induction heater; or the processor repeatedly executes starting and stopping the drive of the induction heater to maintain the temperature detected by the first temperature sensor at the first temperature.

[0081] 18. The washing apparatus according to claim 1, characterized in that it comprises:

[0082] Outer drum;

[0083] A roller, rotatably disposed inside the outer barrel, holds the object;

[0084] An induction heater is installed on the outer barrel to heat the circumferential surface of the roller;

[0085] A temperature sensor detects the temperature of the air in the space between the outer barrel and the roller;

[0086] A power supply device that supplies power to the washing device from an external power source;

[0087] A relay, electrically connected to the power supply device, applies or disconnects the current flow from the power supply device to the induction heater. The relay is normally open, thereby disconnecting the current flow from the power supply device to the induction heater.

[0088] The processor controls the relay to drive the induction heater by applying a control signal to the relay;

[0089] The relay is electrically connected to the processor via a control line. The control signal causes the relay to switch from an off state to an on state, thereby applying current flow from the power supply device to the induction heater, or causes the relay to switch from an on state to an off state, thereby cutting off current flow from the power supply device to the induction heater.

[0090] Each feature of the foregoing embodiments may be combined in other embodiments, as long as they do not contradict or mutually exclusive. Attached Figure Description

[0091] Figure 1 A cross-section of a washing apparatus according to an embodiment of the present invention is shown.

[0092] Figure 2 This is a block diagram illustrating the control structure of a washing device according to an embodiment of the present invention.

[0093] Figure 3 This is a diagram illustrating the principle of changing the output of the induction heater in a washing apparatus according to an embodiment of the present invention.

[0094] Figure 4 An example is shown where an induction heater and an upper temperature sensor are mounted on the outer tub in a washing apparatus according to an embodiment of the present invention.

[0095] Figure 5 The image shows the upper and lower temperature sensors protruding into the interior of the outer barrel and installed in this state.

[0096] Figure 6 The status of the lower temperature sensor installed inside the outer tank and the location of the cooling water port are shown.

[0097] Figure 7 and Figure 8 The temperature changes during the drying process under different drying loads are shown.

[0098] Figure 9 This is a block diagram of the safety control structure of a washing device according to an embodiment of the present invention. Detailed Implementation

[0099] Below, refer to Figure 1 A washing apparatus according to an embodiment of the present invention will be described.

[0100] In the following embodiments, for ease of explanation, specific components may be shown or described in an enlarged or reduced manner. This also helps in understanding the present invention.

[0101] Therefore, the present invention is not limited to the following embodiments. Those skilled in the art can make various modifications and variations based on this description, and such modifications and variations are all within the scope of the present invention.

[0102] A washing apparatus according to an embodiment of the present invention may include: a body 1 forming the exterior; an outer tub 2 disposed inside the body; and a drum 3 rotatably disposed inside the outer tub 2 and accommodating an object (for example, an object to be washed, an object to be dried, or an object to be cared for). For example, when washing clothes with wash water, the object can be referred to as the object to be washed; when drying wet clothes with hot air, the object can be referred to as the object to be dried; and when caring for dry clothes with hot air, cold air, or steam, the object can be referred to as the object to be cared for. Therefore, the drum 3 of the washing apparatus can be used to perform washing, drying, or caring for clothes.

[0103] The body 1 may include a body opening located at the front of the body 1 to allow objects to be placed in or removed. The body 1 may include a door 12 rotatably mounted on the body to open the body opening.

[0104] The door 12 may consist of a ring-shaped door frame 121 and a viewing window 122 located in the center of the door frame.

[0105] To aid in understanding the detailed structure of the washing device described below, the direction is defined as follows: with the center of the body 1 as a reference, the direction toward the door 12 is defined as front.

[0106] Furthermore, the opposite direction to the direction facing the door 12 can be defined as rear, and the right and left directions can be naturally defined according to the front and back directions defined above.

[0107] The outer barrel 2 is configured as a cylindrical shape with its length axis parallel to or at an angle of 0 to 30° to the bottom surface of the machine body, forming a space capable of storing water. Furthermore, an outer barrel opening 21 is provided in front of the outer barrel 2 to communicate with the opening of the machine body.

[0108] The outer tub 2 can be fixed to the bottom surface (bottom surface) of the machine body 1 by means of a lower support part 13 including a support rod 13a and a shock absorber 13b connected to the support rod 13a, thereby reducing the vibration of the outer tub 2 caused by the rotation of the roller 3.

[0109] Furthermore, an elastic support part 14 fixed to the top surface of the body 1 can be connected to the top surface of the outer barrel 2, which can also reduce the vibration that occurs in the outer barrel 2 and is transmitted to the body 1.

[0110] The roller 3 is configured as a cylinder whose length axis can be parallel to or maintain an angle of 0 to 30° with the bottom surface of the machine body to accommodate objects. Furthermore, a roller opening 31 communicating with the outer barrel opening 21 can be provided in front of the roller 3. The angles formed by the central axes of the outer barrel 2 and the roller 3 with respect to the bottom surface can be the same.

[0111] Furthermore, the drum 3 may include multiple through holes 33, which are configured to penetrate the outer circumferential surface. Air and washing water between the inside of the drum 3 and the inside of the outer tub 2 can enter and exit through the through holes 33.

[0112] Lifting ribs 35 can also be provided on the inner circumferential surface of the drum 3. When the drum rotates, the lifting ribs 35 are used to stir the object. The drum 3 can be rotated by the drive unit 6 located behind the outer barrel 2.

[0113] The drive unit 6 may include: a stator 61, which is fixed to the back of the outer barrel 2; a rotor 63, which rotates by electromagnetic interaction with the stator; and a rotating shaft 65, which passes through the back of the outer barrel 2 and connects the roller 3 and the rotor 63.

[0114] The stator 61 can be fixed to the rear surface of the bearing housing 66 located on the back of the outer barrel 2. The rotor 63 can include a rotor magnet 632 located on the radially outer side of the stator and a rotor housing 631 connecting the rotor magnet 632 and the rotating shaft 65.

[0115] Multiple bearings 68 supporting the rotating shaft 65 can be provided inside the bearing housing 66.

[0116] Furthermore, a star wheel 67 can be provided on the back of the roller 3. The star wheel 67 makes it easy to transmit the rotational force of the rotor 63 to the roller 3. The rotating shaft 65 that transmits the rotational power of the rotor 63 can be fixed to the star wheel 67.

[0117] In addition, the washing device of one embodiment of the present invention may also include a water supply pipe 51 for receiving water from the outside, the water supply pipe 51 forming a flow path for supplying water to the outer tub 2.

[0118] Furthermore, a gasket 4 can be provided between the opening of the body 1 and the opening 21 of the outer tub. The gasket 4 is used to prevent water inside the outer tub 2 from leaking into the body 1 and to prevent vibration of the outer tub 2 from being transmitted to the body 1.

[0119] In addition, the washing device of one embodiment of the present invention may also include a drain section 52, which drains the water inside the outer tub 2 to the outside of the machine body 1.

[0120] The drainage section 52 may include: a drain pipe 522 that forms a drainage path for water to move inside the outer tub 2; and a drain pump 521 that generates a pressure difference inside the drain pipe 522 to drain water through the drain pipe 522.

[0121] More specifically, the drain pipe 522 may include: a first drain pipe 522a, which connects the bottom surface of the outer tub 2 and the drain pump 521; and a second drain pipe 522b, one end of which is connected to the drain pump 521 to form a flow path through which water moves to the outside of the body 1.

[0122] Furthermore, the washing apparatus of one embodiment of the present invention may also include a heating unit 8 for induction heating of the drum 3.

[0123] The heating element 8 is mounted on the circumferential surface of the outer drum 2. It inductively heats the circumferential surface of the drum 3 by applying an electric current to a coil wound with wires, thereby generating a magnetic field. Therefore, the heating element can be called an induction heater. When the induction heater is activated, the outer circumferential surface of the drum opposite to the induction heater 8 can be heated to a very high temperature in a very short time.

[0124] The heating element 8 can be controlled by a control unit 9 fixed to the body 1. The control unit 9 controls the drive of the heating element 8, thereby controlling the temperature inside the outer tub. The control unit 9 may include a processor that controls the drive of the washing device, and may also include an inverter processor that controls the heating element. That is, a single processor can be used to control both the drive of the washing device and the drive of the heating element 8.

[0125] However, considering control efficiency and processor overload, the processor that controls the drive of the washing device and the processor that controls the heating element are usually set up independently, and can be interconnected in a communicative manner.

[0126] A temperature sensor 95 can be installed inside the outer tub 2. The temperature sensor 95 can be connected to the control unit 9 to transmit the temperature information inside the outer tub 2 to the control unit 9. In particular, the temperature sensor 95 can be configured to sense the temperature of the washing water or humid air. Therefore, this temperature sensor 95 can be referred to as a washing water temperature sensor.

[0127] The temperature sensor 95 can be located near the bottom inside the outer drum. Therefore, the temperature sensor 95 can be located at a position lower than the bottom of the drum. Figure 1The temperature sensor 95 is shown positioned in contact with the bottom surface of the outer tub. However, it is preferable to position it at a predetermined distance from the bottom surface. This is to allow the washing water or air to surround the temperature sensor, thereby enabling accurate measurement of the temperature of the washing water or air. Furthermore, the temperature sensor 95 can be installed from the bottom to the top of the outer tub, but it can also be installed from the front to the rear of the outer tub. That is, it can be installed through the front surface (the surface forming the opening of the outer tub) rather than through the circumferential surface of the outer tub.

[0128] Therefore, when the washing device heats the washing water using the induction heater 8, a temperature sensor can detect whether the washing water has been heated to the target temperature. The operation of the induction heater can be controlled based on the detection result of this temperature sensor.

[0129] Furthermore, when all the washing water has been drained, the temperature sensor 95 can detect the temperature of the air. Since there is residual washing water or cooling water at the bottom of the outer tub, the temperature sensor 95 senses the temperature of the humid air.

[0130] Additionally, a washing apparatus according to one embodiment of the present invention may include a drying temperature sensor 96. The installation location and temperature measurement object of the drying temperature sensor 96 may differ from those of the aforementioned temperature sensor 95. The drying temperature sensor 96 can detect the temperature of the heated air, i.e., the drying temperature, via the induction heater 8. Therefore, it is possible to detect whether the air has been heated to the target temperature using the temperature sensor. The drive of the induction heater can be controlled based on the detection result of this drying temperature sensor.

[0131] The drying temperature sensor 96 is located on the upper part of the outer drum 2 and can be positioned near the induction heater 8. That is, the drying temperature sensor 96 can be positioned outside the projection surface of the induction heater 8 and on the inner side of the outer drum 2 to detect the temperature of the outer circumferential surface of the drum 3 opposite to the drying temperature sensor 96. The aforementioned temperature sensor 95 can be configured to detect the temperature of the surrounding water or air, and the drying temperature sensor 96 can be configured to detect the temperature of the drum or the drying air temperature around the drum.

[0132] The roller 3 is a rotating structure, therefore, the temperature of the outer peripheral surface of the roller can be indirectly detected by detecting the temperature of the air near the outer peripheral surface of the roller 3.

[0133] The temperature sensor 95 can be configured to determine whether to continuously drive the induction heater to the target temperature or to change the output of the induction heater. The drying temperature sensor 96 can be configured to determine whether the drum is overheating. When the drum is determined to be overheating, the driving of the induction heater can be forcibly stopped.

[0134] Furthermore, the washing apparatus of one embodiment of the present invention can also have a drying function. In this case, the washing apparatus of one embodiment of the present invention can be referred to as a washer-dryer combo. For this purpose, a fan 72 for supplying air into the outer tub 2 and a duct 71 provided with the fan 72 may also be included. Of course, the drying function can be performed even without such a structure. That is, the air can be cooled on the inner circumference of the outer tub, and the moisture can be condensed and discharged. In other words, drying can be performed by condensing moisture itself even without air circulation. In order to perform moisture condensation more effectively and improve drying efficiency, cooling water can be supplied to the inside of the outer tub. The larger the surface area of ​​the cooling water in contact with the outer tub, that is, the larger the surface area of ​​the cooling water in contact with the air, the better. For this purpose, the cooling water can be widely distributed and supplied to the back, one or both sides of the outer tub. With this cooling water supply, the cooling water flows along the inner surface of the outer tub, thereby preventing the cooling water from flowing into the drum. Therefore, the duct or fan structure for drying can be omitted, and it can be easily manufactured.

[0135] At this time, there is no need to set up a separate heater for drying. That is, drying can be performed using the induction heater 8. In other words, the washing water heating during washing, the heating of the object during spin-drying, and the heating of the object during drying can all be performed using a single induction heater.

[0136] When the drum 3 and induction heater 8 are driven, the entire outer circumference of the drum can be heated. The heated drum exchanges heat with the wet laundry, thereby heating the laundry. Of course, the air inside the drum can also be heated. Therefore, when air is supplied to the inside of the drum 3, the air that has undergone heat exchange and evaporated moisture can be discharged to the outside of the drum 3. That is, the air can circulate between the pipe 71 and the drum 3. Of course, the fan 72 can be driven to circulate the air.

[0137] The air supply and exhaust positions can be determined to ensure that heated air is evenly supplied to the object being dried and that humid air is smoothly discharged. For this purpose, air can be supplied from the upper front of the drum 3 and discharged from the lower rear of the drum 3, i.e., the lower rear of the outer drum.

[0138] Air discharged from the lower rear of the outer drum flows along pipe 71. Within pipe 71, cooling water supplied to the inside of pipe 71 via condensate flow path 51 can condense the moisture in the humid air. As the moisture in the humid air is condensed, it transforms into low-temperature dry air, which can then flow along pipe 71 and be resupplyed to the inside of drum 3.

[0139] Therefore, since the air itself is not directly heated, the temperature of the heated air may be lower than the temperature of the air heated by a conventional heater in a dryer. Thus, it is expected that this will prevent damage or deformation of clothing caused by high temperatures. Of course, the clothes may overheat between the heated drum and the clothes.

[0140] However, as mentioned above, the induction heater is driven together with the roller. As the roller is driven, the clothes repeatedly rise and fall. Furthermore, the heating position of the roller is at the top rather than the bottom, thus effectively preventing the clothes from overheating.

[0141] A control panel 92 may be provided on the front or top surface of the washing device. The control panel can provide a user interface, allowing for various user inputs and the display of various information. That is, an operation unit for user operation and a display unit for displaying information to the user can be provided on the control panel 92.

[0142] Figure 2 A system block diagram of a washing apparatus according to an embodiment of the present invention is shown.

[0143] The control unit 9 can control the driving of the heating unit, i.e., the induction heater 8, through the temperature sensor 95 and the drying temperature sensor 96. The control unit 9 can control the driving of the drive unit 6 that drives the roller, as well as the driving of various sensors and hardware, through the motor. The control unit 9 can perform the control of various valves or pumps, as well as the control of fans, for purposes such as water supply, drainage, and supply of cooling water.

[0144] In particular, according to this embodiment, a cooling water valve 97 may be included, which is used to convert high-temperature, high-humidity air / environment into low-temperature, dry air / environment. The cooling water valve 97 supplies cold water to the inside of the outer tank or the inside of the pipe to cool the air, thereby condensing the moisture inside the air.

[0145] The drain pump 521 may be driven periodically or intermittently during dehydration and / or during cooling water supply.

[0146] According to this embodiment, a door lock device 98 may be included. A device used to prevent the door from being opened during the operation of the washing device can be referred to as a door lock device. According to this embodiment, the door is restricted from being opened not only during the operation of the washing device, but also after the washing device has finished operating, when the internal temperature is above a set temperature.

[0147] Furthermore, the control unit 9 can control various display units 922 provided on the control panel 92. It can also receive signals from various operation units 921 provided on the control panel 92 and control the overall operation of the washing device based on these signals.

[0148] Additionally, the control unit 9 may include a main processor that controls the normal drive of the washing device and an auxiliary processor that controls the drive of the induction heater. The main processor and the auxiliary processor may be set up independently and interconnected in a communicative manner.

[0149] According to one embodiment of the present invention, the output of the induction heater can be varied. Within permissible conditions or ranges, the heating time can be reduced by maximizing the output of the induction heater, thereby achieving optimal results. For this purpose, an instantaneous power output unit 99 may be included in this embodiment.

[0150] Below, refer to Figure 3 The principle of changing the output of the induction heater, which can be applied in one embodiment of the present invention, will be explained in detail. To change the output of the induction heater, an instantaneous power output unit 99 can be used. The washing device can be preset with a maximum allowable power. That is, the washing device can be manufactured to operate with an instantaneous maximum power less than the preset power value. Figure 3 In this context, the preset power value is represented as the system's allowable power.

[0151] In this embodiment, the most powerful hardware used in the washing apparatus can be the motor that drives the induction heater 8 and the drum, i.e., the drive unit 6.

[0152] like Figure 3 As shown, the power used in the drive unit, i.e., the instantaneous power, tends to increase with increasing RPM. Furthermore, the instantaneous power used in the drive unit tends to increase with increasing laundry eccentricity. Moreover, it can be seen that if the power used in the drive unit increases, the instantaneous power of the overall system also tends to increase. That is, it can be seen that a large portion of the instantaneous power of the overall system is the power used in the drive unit.

[0153] During heating, dehydration, or drying, not only the induction heater 8 and drive unit 6 consume power, but also the control panel 92, various valves 97, drain pump 521, and various sensors 95 and 96 consume power. Therefore, as Figure 3 As shown, when determining the allowable power value in a washing device system, a margin can be considered to preset the maximum total power that can be used in the washing device.

[0154] In existing washing machines, the output of the jacketed heater during heating and spin-drying is preset. That is, the output of the jacketed heater is preset to be less than the maximum power value during heating and spin-drying, excluding the jacketed heater, minus the maximum power value during heating and spin-drying.

[0155] A simplified explanation is as follows: When the allowable power of the washing system is 100 and the margin is 10, the maximum total power can be 90. When the maximum power value (excluding the jacketed heater) during heating and spin-drying is 70, the output of the jacketed heater must be less than 20. Here, the maximum power value (excluding the jacketed heater) can be the sum of the power values ​​of all hardware (excluding the jacketed heater) under the maximum RPM and the maximum laundry eccentricity environment (extreme environment).

[0156] Not only is the output variation of the sheathed heater itself very limited, but when using this type of sheathed heater, it cannot be used to its maximum extent in general environments that are not extreme environments.

[0157] To address this problem, this embodiment may include an instantaneous power output unit 99. That is, it may include an output unit that calculates instantaneous power or calculates and outputs instantaneous power. This instantaneous power output unit 99 may be provided independently of the control unit 9, or a portion of the instantaneous power output unit 99 may be provided independently of the control unit or included within the control unit.

[0158] As described above, during heating and dehydration, and drying, the hardware using maximum power, other than the induction heater 8, can be a motor, i.e., the drive unit 6. Furthermore, the maximum power values ​​of the other hardware, besides the induction heater and the drive unit, can be preset during heating and dehydration. The maximum output of the other hardware is relatively small.

[0159] Therefore, the instantaneous power output unit 99 can be configured to estimate or calculate the instantaneous power of the motor driving the roller.

[0160] As an example, the instantaneous power of the motor can be calculated by detecting the input current and DC link voltage to the motor.

[0161] As an example, the instantaneous power of the motor can be calculated using the input current and input voltage input to the motor.

[0162] As an example, the instantaneous power of the motor can be calculated using the input current to the motor and the AC input voltage applied to the washing device.

[0163] Therefore, the instantaneous power output unit 99 includes a device, element, or circuit for detecting current and voltage, and may be a unit that outputs the calculated instantaneous power of the motor.

[0164] When the instantaneous power of the motor is calculated, the possible output of the induction heater 8 can be calculated. That is, the possible output of the induction heater can be defined as the value obtained by subtracting the calculated instantaneous power of the motor and other hardware calculations from the total power upper limit.

[0165] Here, the instantaneous power of the motor can vary by a relatively large margin. This is because the RPM variation and the eccentricity of the laundry load can be large. Therefore, it is preferable to calculate the motor power as the instantaneous power, i.e., the current power. On the other hand, the maximum output value of other hardware is relatively small and varies little, so it can be preset to a maximum value and used as a fixed value. Of course, the maximum output value of other hardware can also be calculated as instantaneous power. However, since the output value of other hardware is relatively small, it is preferable to use it as a fixed value and exclude the need for additional devices or circuits for detecting and calculating power.

[0166] Furthermore, the instantaneous power output unit 99 can be configured to estimate or calculate the overall instantaneous power of the washing apparatus. For example, the overall instantaneous power of the washing apparatus can be calculated using the AC input current and AC input voltage applied to the washing apparatus. The overall instantaneous power during heating and spin-drying can be the sum of the outputs of the induction heater, motor, and other hardware. Therefore, the difference between the overall instantaneous power and the upper limit of the total power indicates the additional power that can be increased by increasing the output of the induction heater. For example, if the current overall instantaneous power is 50 and the upper limit of the total power is 90, it means that the output of the induction heater can be increased by 40.

[0167] Therefore, according to this embodiment, the output of the induction heater is maximized under the current possible power conditions of the system. That is, when the motor uses a large power, the output of the heater can be reduced, and when the motor uses a small current, the output of the heater can be further increased.

[0168] When the output of the induction heater is controlled using this instantaneous power output unit 99, the heating time can be reduced, and the induction heater can be safely controlled. Given the same total heat required for drying and dehydration, shortening the heating time reduces heat loss to the outside. Therefore, energy consumption is reduced. Furthermore, drying and dehydration times can be reduced. This increases user convenience.

[0169] As described above, in the washing apparatus of this embodiment, both the heating for washing and the heating for drying can be performed by the induction heater 8. That is, a washing apparatus that can perform both washing and drying can be provided.

[0170] When the drum containing a wet object is heated and rotated, heat transfer occurs through contact between the drum and the object. As a result, the object is heated and the moisture evaporates.

[0171] In this embodiment, a separate circulation pipe for generating forced airflow for drying may not be necessary. In other words, moisture evaporation and condensation can occur within the space inside the outer drum.

[0172] The drum is directly heated by an induction heater, therefore its temperature is relatively the highest. Furthermore, heat is transferred from the drum to the object, so the temperature inside the drum is higher than the temperature outside the drum, i.e., the temperature of the space between the drum and the outer drum. Therefore, when observing the overall space inside the outer drum and the heat transfer path, the temperature of the inner wall or inner surface of the outer drum is the lowest.

[0173] Due to the essentially enclosed internal space of the outer drum, natural convection occurs within it. Moist air that has evaporated rises or moves laterally and comes into contact with the inner surface of the outer drum, causing condensation. The condensate produced by this condensation moves along the inner surface of the outer drum to the lower part of the drum. Furthermore, the air that has removed moisture descends and flows back into the drum, where it encounters the evaporated water vapor and can be reheated. This natural convection effectively removes moisture from the object, thus enabling drying.

[0174] Furthermore, the drying of objects has always been problematic, with issues of under-drying and over-drying. Therefore, it is crucial to perform drying to achieve the desired moisture content. For this reason, it is essential to determine the drying end point when to stop heating the object.

[0175] In the aforementioned existing dryers or washer-dryer combos, there is an air circulation structure. Therefore, it is difficult for the present invention to utilize the same type of drying end time determination logic or sensors as the prior art.

[0176] For this reason, the purpose of this embodiment is to provide a drying end time point determination logic and sensor structure that are different from those of existing dryers or washer-dryer combos.

[0177] For reference Figure 2 As described, the washing apparatus of this embodiment may include two temperature sensors 95 and 96. One temperature sensor 95 serves as a temperature sensor for sensing the temperature of the washing water, and it may be installed inside the lower part of the outer tub.

[0178] The control unit or processor 9 controls the heating of the washing water and the driving of the induction heater based on the temperature detected by the temperature sensor 95 during washing. As an example, when the target temperature for heating the washing water is 60 degrees Celsius, the processor 9 can heat the washing water by driving the induction heater until the temperature of the washing water is detected by the temperature sensor 95 as 60 degrees Celsius.

[0179] Washing water is water, so it is difficult to heat it to over 100 degrees Celsius under normal conditions or environments. However, the drum is made of metal and is directly heated by an induction heater, so it can be easily heated to 160 degrees Celsius even in a very short time.

[0180] Therefore, a temperature sensor 96, independent of the washing water temperature sensor 95, can be added to prevent the drum from overheating and / or control the temperature of the air inside the outer tub.

[0181] The temperature sensor 96 is configured not to come into contact with the washing water; therefore, it can be referred to as the drying temperature sensor 96. The installation location of this drying temperature sensor 96 is crucial. This is because it is essential to optimally sense the air temperature inside the outer tub and to effectively predict the temperature of the rotating drum.

[0182] Below, refer to Figures 4 to 5 The installation location of the drying temperature sensor 96 is described in detail.

[0183] like Figures 4 to 5 As shown, the induction heater 8 can be installed on the upper part of the outer drum. That is, the induction heater 8 can be installed on the upper outer circumferential surface of the outer drum. Due to this installation position of the induction heater 8, the upper outer circumferential surface of the drum can be heated by the induction heater 8.

[0184] When the drum is stopped, the object inside the drum does not contact the upper part of the drum. Therefore, the position of the induction heater 8 is used to effectively prevent the object from overheating. Thus, the induction heater 8 can be controlled to be driven as the drum rotates, which means that the object can be heated evenly.

[0185] The installation location of the drying temperature sensor 96 is particularly important here. This is because it is essential to optimally detect both the temperature of the heated drum and the air temperature inside the outer drum.

[0186] Preferably, the drying temperature sensor 96 can be mounted directly below the induction heater 8 to sense the air temperature of the outer circumferential surface of the drum, where the temperature is highest. However, a very large magnetic field change is generated directly below the induction heater 8 to inductively heat the drum. This magnetic field change may affect the drying temperature sensor 96, which has a low current intensity.

[0187] Therefore, the preferred installation position of the drying temperature sensor 96 is on one side of the induction heater 8, and at a position away from the projection surface of the induction heater 8.

[0188] When viewed from the front, the drying temperature sensor 96 can be installed on the left or right side of the induction heater 8.

[0189] Here, the interior space of the outer barrel does not have to be a completely sealed space. That is, an air vent or connection 28 that allows the interior space of the outer barrel to communicate with the outside can be formed in the outer barrel. This is to prevent safety accidents that may occur if animals or children enter the interior of the outer barrel and the door is closed, even if the interior space of the outer barrel is completely sealed.

[0190] When viewing the outer tub from the front, if the connection port 28 is installed on the left side of the outer tub, the drying temperature sensor 96 is preferably installed on the right side of the outer tub. If the connection port 28 is installed on the right side of the outer tub, the drying temperature sensor 96 is preferably installed on the left side of the outer tub. This is because the area near the connection port 28 is easily affected by the cooler external air around the outer tub.

[0191] The drying temperature sensor 96 can be installed so that it extends from the outside of the outer tub to the inside of the outer tub. Therefore, the signal line or wire of the drying temperature sensor 96 is located on the outside of the outer tub, and the sensing part for sensing can be installed so that it protrudes radially inward from the inner circumference of the outer tub.

[0192] Therefore, the drying temperature sensor 96 directly senses the air temperature in the space between the outer circumferential surface of the drum and the inner circumferential surface of the outer drum. The temperature of the outer circumferential surface of the drum can be indirectly and experimentally sensed or predicted through this temperature sensing method.

[0193] The drive of the induction heater 8 can be controlled based on the temperature detected by the drying temperature sensor 96. That is, the drying temperature sensor 96 can be used to prevent the drum from overheating and the temperature inside the outer drum from overheating.

[0194] The induction heater 8 can be driven until the target heating temperature is reached. For example, the target heating temperature can be set approximately between 95 and 99 degrees Celsius. That is, the induction heater is driven until the target heating temperature is detected by the drying temperature sensor 96, at which point the drive can be stopped. Furthermore, if a temperature drop occurs, the induction heater can be driven again to perform start / stop control of the induction heater near the target heating temperature.

[0195] Here, the target heating temperature is preferably not set above 100 degrees Celsius. This is because when the detected air temperature is above 100 degrees Celsius, it indicates a superheated steam state rather than a wet steam state. That is, the heat consumed to convert wet steam into superheated steam is greater than the heat required to evaporate water, thus meaning a waste of energy. Furthermore, the generation of superheated steam indicates that the drum temperature is heated to approximately 160 degrees Celsius or higher, which may indicate drum overheating. This could also lead to thermal deformation or damage to the outer plastic drum. This is also why the washing water in the washing device is only heated to a temperature below 100 degrees Celsius.

[0196] During drying, the drum heating should supply maximum heat in the shortest time within a safe range. Therefore, as drying is performed, the temperature detected by the drying temperature sensor 96 converges to the target heating temperature. That is, it gradually increases from room temperature and converges to the target heating temperature. Of course, after initially reaching the target heating temperature, the temperature can be varied between the target heating temperature and the induction heater re-drive temperature by repeatedly starting / stopping the induction heater. The induction heater re-drive temperature can be set to approximately 2 to 3 degrees Celsius lower than the target heating temperature. Of course, it is not limited to this.

[0197] As a result, the temperature detected by the drying temperature sensor did not exceed the target heating temperature. This is because heating was stopped before this occurred.

[0198] As described below, the basic functions and characteristics of this drying temperature sensor can be used to perform drying degree or humidity detection. This can further determine the drying end time.

[0199] Below, refer to Figures 5 to 6 The installation location of the washing water temperature sensor 95 is described in detail.

[0200] The washing water temperature sensor 95 is configured to detect the temperature of the washing water, and therefore can be installed at the bottom of the outer tub. Thus, the installation position of the washing water temperature sensor 95 can be the same as that of a general washing machine. That is, it can be installed inside the lower part of the outer tub, immersed in the washing water to detect its temperature. Furthermore, the washing water temperature sensor 95 can be installed with a gap between the bottom and top surfaces inside the outer tub. Of course, it is preferable to install it at the bottom compared to the bottom surface of the drum.

[0201] As can be seen here, the drying temperature sensor 96 is located inside the upper part of the outer tub, and the washing water temperature sensor 95 is located inside the lower part of the outer tub. Therefore, the drying temperature sensor 96 can be referred to as the upper temperature sensor, and the washing water temperature sensor 95 can be referred to as the lower temperature sensor.

[0202] Furthermore, the drying temperature sensor 96 and the washing water temperature sensor 95 detect the temperatures of the air and washing water, respectively, and the processor can control the drive of the induction heater based on their temperatures. Therefore, the drying temperature sensor and the washing water temperature sensor are preferably thermistors capable of detecting temperature linearly or in stages.

[0203] Existing sheathed heaters are installed at the bottom of the outer tub, penetrating the rear or front wall. This mounting and sealing structure can be used to install the wash water temperature sensor 95. While not preferred, in this embodiment, both the induction heater and the sheathed heater can be driven for drying and heating of the wash water. However, as mentioned above, the sheathed heater can be omitted, and the washing water temperature sensor can be installed using the mounting and sealing structure of the sheathed heater. This minimizes deformation of the existing outer tub shape or surrounding components. This means that the increase in initial equipment or mold investment can be minimized, as only minor modifications are needed based on existing equipment or molds.

[0204] like Figures 5 to 6 As shown, a downwardly recessed condensate reservoir 29 is preferably formed in the lower part of the inner interior of the outer barrel. When high-temperature wet steam comes into contact with and is cooled by the inner surface of the outer barrel, condensate is generated. This condensate flows along the inner surface of the outer barrel and collects in the condensate reservoir 29, which forms the lowest part of the inner interior of the outer barrel.

[0205] This condensate reservoir 29 can be formed at the rear of the outer tub, making it easy for condensate to drain. Of course, during washing, the wash water can be stored in the condensate reservoir 29, and the lower part of the condensate reservoir 29 is connected to the drain pump, so that when draining, practically all the wash water in the outer tub can be drained.

[0206] Here, the washing water temperature sensor 95 is preferably located at the upper part of the condensate reservoir 29. Specifically, it can extend from the rear wall of the outer tub to the front and be located at a position spaced upwards from the bottom of the condensate reservoir.

[0207] Unlike the washing water, the amount of condensate stored inside the outer tub is small. Furthermore, during drying, the condensate is not continuously stored inside the outer tub but is drained intermittently or periodically. Therefore, the maximum condensate level during drying is relatively low. This means that during drying, the washing water temperature sensor 95 senses the air temperature surrounding the condensate, rather than directly sensing the temperature of the condensate itself.

[0208] In other words, during drying, the drying temperature sensor senses the temperature of the humid or dry air that is located at the highest relative position and has the highest temperature, while the washing water temperature sensor senses the temperature of the humid or dry air that is located at the lowest relative position and has the lowest temperature.

[0209] During the drying process, the temperature of the condensate can vary. That is, the sensed temperature may differ depending on where the condensate flows into the outer drum. This can reduce the reliability of the condensate temperature itself during drying. However, the temperature of the air near the condensate is likely reliable. This is because natural convection occurs, and therefore, the rate of temperature change of the air at the very bottom of the outer drum is extremely small.

[0210] Therefore, as Figures 5 to 6 As shown, in this embodiment, the washing water temperature sensor 95 is preferably installed with a distance from the bottom surface of the outer tub upwards. Considering the amount of condensate, the washing water temperature sensor 95 is preferably located approximately 10mm to 15mm above the bottom surface of the condensate mounting section.

[0211] The applicant has disclosed a washing apparatus using an induction heater in Korean Patent Application No. 10-2017-0101333 (hereinafter referred to as the "prior application"). Therefore, the disclosures in the prior application can be applied in the same way to an embodiment of the present invention, provided they do not contradict or exclude this specification. In particular, the induction heater structure or mounting structure and the cooling water supply structure can be applied in the same way to an embodiment of the present invention.

[0212] As an example, Figure 4 The housing 8A of the induction heater 8 shown, the fan housing 8C formed in the housing, and the fan mounting portion 8B or fan formed in the fan housing 8C can be the same as in the prior application. Of course, a coil is provided inside the induction heater housing 8A.

[0213] In particular, such as Figure 6 As shown, a cooling water port 28 can be provided on the rear wall of the outer tub 2. This allows room temperature water to flow through the cooling water port 28 along the inner circumference of the outer tub to the front and bottom.

[0214] A rib 28a extending forward can be formed at the outlet portion of the cooling water port 28. Water discharged through the cooling water port 28 flows along the rib 28a and descends. Therefore, the cooling water flows downward like a curtain. This increases the contact area between the cooling water and the inner circumferential surface of the outer tank.

[0215] Cooling water can be discharged through the cooling water port 28 to lower the air temperature inside the outer tub after heating, dehydration, or drying. This is because if the air temperature inside the outer tub is too high when the user opens the door, it may cause a safety accident or discomfort to the user.

[0216] Additionally, the cooling water can be discharged during the drying process. This is because as the cooling water flows along the inner circumference of the outer drum, it further promotes the condensation of moisture in the wet steam. The cooling water, along with the condensate generated from the condensation of moisture in the humid air, flows to the lower part of the outer drum.

[0217] As described above, the cooling water flows in a thin, dispersed manner on the inner circumferential surface of the outer barrel, thus significantly increasing the heat transfer area. That is, effective water condensation can occur using a small amount of cooling water.

[0218] As described above, this embodiment includes an upper temperature sensor 96 for sensing the temperature of the drum or the air temperature around the drum, and a lower temperature sensor 95 for sensing the temperature of the washing water. The detection values ​​from these temperature sensors can be used to control the operation of the induction heater. Furthermore, as described above, the lower temperature sensor 95 can sense the temperature near the condensate during drying.

[0219] In this embodiment, these temperature sensors 95 and 96 can be used to determine the degree of drying or humidity, and can also be used to determine the drying end time. In other words, in addition to their respective main functions, the temperature sensors 95 and 96 can also have the auxiliary function of determining the drying end time.

[0220] Below, refer to Figure 7 and Figure 8 The characteristics of using the upper temperature sensor 96 and the lower temperature sensor 95 to determine the drying end time are described in detail.

[0221] Figure 7 and Figure 8 The diagram illustrates the temperature changes over time during the drying process, detected by the upper and lower temperature sensors, and the changes in the temperature difference (ΔT). As an example, in... Figure 7 The diagram shows a drying load of 7 kg, and... Figure 8 The figure shows the case where the drying load is 3 kg.

[0222] In a drying process that uses heated drums to dry wet objects, temperature changes and temperature differences vary depending on the drying zone.

[0223] In the initial stage of drying, sensible heat exchange occurs by heating the object through a heated drum. That is, most of the heat provided is used for sensible heat exchange, meaning that very little moisture evaporates at this stage.

[0224] Therefore, from the start of drying until near the end of the initial drying period, the temperature of the upper air inside the outer drum gradually increases, reaching the target heating temperature. At this time, the temperature of the lower air inside the outer drum also gradually increases, however, at a relatively small rate. Furthermore, ΔT increases rapidly. This is because the upper temperature sensor senses the temperature near the heating source, while the lower temperature sensor senses the temperature furthest from the heating source. Moreover, as heating continues, the change in ΔT decreases.

[0225] As drying continues, moisture evaporates, and the heating heat of the wet steam is the same as or similar to the cooling heat of the cooling water. Therefore, the temperature change detected near the condensate storage area at the bottom of the outer drum is very small, or the temperature may remain constant. At this time, ΔT decreases. This is because the temperature detected by the upper temperature sensor converges to the heating target temperature, and the temperature detected by the lower temperature sensor converges to the highest temperature of the condensate.

[0226] As drying continues, moisture evaporation reaches saturation. That is, maximum moisture evaporation occurs. Up to this point, ΔT can be maintained. That is, the temperature changes detected by the upper temperature sensor and the lower temperature sensor may be very small.

[0227] After the water reaches saturation point, the amount of water evaporated gradually decreases. Therefore, at this point, the cooling heat from the cooling water exceeds the heating heat from the drying air. Since the cooling water itself is supplied from the outside at room temperature, its temperature, detected by the lower temperature sensor, gradually decreases. In other words, the amount of condensate produced by the cooling water decreases because its temperature drops.

[0228] As a result, it can be seen that when the temperature detected by the lower temperature sensor reaches a certain level, almost no moisture evaporation occurs. In particular, when the temperature detected by the upper temperature sensor is taken as the constant target heating temperature, if ΔT decreases and reaches a predetermined value, it can be concluded that almost no moisture evaporation occurs.

[0229] Therefore, the degree of drying or humidity can be indirectly estimated very accurately by detecting temperature changes or temperature values ​​and / or changes in ΔT and ΔT values ​​detected by the lower temperature sensor. This means that this principle can be used to determine the end time of heating.

[0230] Drying load can be defined as the weight of the load used for drying. It can be assumed that the amount of moisture to be evaporated is proportional to the weight of the load. When the drying load is large, sensible heat exchange, i.e., the heat used for preheating, increases, and the time also increases. Under the premise of supplying the same amount of heat per hour, the rate of temperature increase caused by heating decreases as the drying load increases.

[0231] Figure 7The temperature change rate shown in the figure for a drying load of 7 kg can be considered to be less than Figure 8 The figure shows the rate of temperature change when the drying load is 3 kg. However, it can be seen that the Y-axis (temperature) scale is the same for both, while the X-axis (time) scale is different. Therefore, it can be seen that the rate of temperature change is large when the drying load is substantially small.

[0232] The temperature change and degree of drying based on this drying load can be obtained experimentally. Experimental results show that, under the same degree of drying, a larger drying load results in a larger ΔT. For example, the drying end time can be determined when the ΔT is 18 degrees Celsius with a drying load of 7 kg and when the ΔT is 15 degrees Celsius with a drying load of 3 kg. That is, even with different ΔT values, drying may end at the same degree of drying due to differences in the drying load.

[0233] Furthermore, the amount of water that clothing can absorb varies depending on its material. For example, cotton absorbs more water than synthetic fibers. Therefore, the total weight of an item is not necessarily proportional to the amount of water that needs to be removed. Also, when drying the same garment, drying it completely wet is different from drying it partially wet. In other words, the amount of water that needs to be removed differs.

[0234] Therefore, the drying load is not determined at the initial loading of the material, but rather preferably during the drying process. That is, the amount of moisture to be removed is determined during the drying process, and the drying end time can be determined based on this.

[0235] Specifically, such as Figure 7 and Figure 8 As shown, the difference in temperature change based on the difference in drying load can be used to determine the drying load.

[0236] That is, it can be seen that the smaller the drying load, the shorter the time for ΔT to reach its maximum value. Furthermore, it can be seen that the smaller the drying load, the smaller the maximum value of ΔT. And, it can be seen that the smaller the drying load, the smaller the minimum value of ΔT.

[0237] Furthermore, it can be seen that, regardless of the drying load, ΔT increases to its maximum value, then decreases to its minimum value, and subsequently gradually increases. This indicates that drying is performed on the premise that the drum is heated to the target heating temperature.

[0238] Here, it can be seen that the maximum value of ΔT is detected before the time point when the upper temperature sensor initially senses the target heating temperature. Furthermore, it can be seen that the minimum value of ΔT is detected after the time point when the upper temperature sensor initially senses the target heating temperature. Therefore, drying can be essentially carried out from the initial sensing of the target heating temperature by the upper temperature sensor, and then the drying load can be determined. That is, the drying load can be determined by the maximum value of ΔT sensed before the time point when the upper temperature sensor initially senses the target heating temperature, or the minimum value of ΔT sensed after the time point, or the time required to reach the maximum value of ΔT or the time required to reach the minimum value of ΔT.

[0239] Once the drying load is determined, the temperature condition for stopping drying can be determined based on the determined load. That is, the temperature or ΔT value detected by the lower temperature sensor can be determined. As an example, when the drying load is determined to be 7 kg, ΔT can be determined to be 18 degrees Celsius. As an example, when the target heating temperature is 98 degrees Celsius and ΔT is 18 degrees Celsius, the temperature detected by the lower temperature sensor can be 80 degrees Celsius. Since the temperature detected by the upper temperature sensor converges to the target heating temperature after the initial detection of the target heating temperature, this target heating value can be a fixed value. Therefore, the drying end time can be determined solely based on the temperature value detected by the lower temperature sensor, without calculating ΔT, which is the difference between the two.

[0240] In addition, according to Figure 7 and Figure 8 The initial drying phase can be defined as the time point from the start of drying until the target heating temperature is detected by the upper temperature sensor, at which point ΔT is at its maximum. Furthermore, the middle drying phase can be defined as the time point from the initial drying phase until ΔT is at its minimum. Finally, the later drying phase can be defined as the time point from the middle drying phase until heating ends based on ΔT or the temperature detected by the lower temperature sensor.

[0241] Drying can be stopped immediately after the later stages of drying. If necessary, cooling can be performed by supplying cooling water and driving the drum without heating, thus ending the drying process.

[0242] To determine the accurate drying load, data from either the time point before or after initially reaching the target heating temperature can be used. Therefore, the preferred time point for determining the drying load is after initially reaching the target heating temperature.

[0243] In addition, the aforementioned drying process is described below from the perspective of control methods.

[0244] A heating step is performed for drying. The heating step refers to simultaneously driving the induction heater while driving the drum. The induction heater can be driven based on the temperature detected by the upper temperature sensor. The induction heater is driven essentially until the target heating temperature is reached, and then the start / stop cycle is repeated to perform the heating step to maintain the target heating temperature. The heating step can be performed continuously from the start to the end of the drying program. That is, the temperature detected by the upper temperature sensor is monitored, and the heating step is performed accordingly.

[0245] A condensation step is performed to remove evaporated moisture. The temperature of the condensate, formed by the natural convection of moisture within the outer drum, is sensed. Specifically, the temperature is detected by a lower temperature sensor, and the condensation step is executed accordingly. The condensation step can be performed continuously from the start to the end of the drying program. Alternatively, cooling water can be added intermittently or periodically.

[0246] Here, the heating and condensation steps can be performed in parallel during the drying process.

[0247] The heating and condensation steps can be terminated when ΔT meets a preset specific value or is sensed by the lower temperature sensor during the drying process, i.e., the heating and condensation can be stopped. Here, the preset specific value can be set according to the drying load. The preset specific value can change as the drying load increases. This has been described above.

[0248] Furthermore, the step of determining the drying load can be performed. When determining the drying load solely based on the total weight, it is not possible to accurately determine the load based on the weight of the clothing and the initial moisture content of the object. Therefore, in this embodiment, the drying load can be effectively determined using temperature data after the initial target heating temperature is reached. That is, regardless of the weight of the clothing and the initial moisture content of the object, the actual amount of moisture that needs to be removed by drying can be accurately determined.

[0249] In particular, in this embodiment, the drying end time can be determined using an upper temperature sensor for controlling the drive of the induction heater and a lower temperature sensor for adjusting the temperature of the washing water, or using only the lower temperature sensor. However, as mentioned above, to determine the accurate load, data from both the lower and upper temperature sensors are required. ΔT data can be derived from these data.

[0250] Therefore, according to this embodiment, the function of determining the drying end time can be additionally added to the two temperature sensors that essentially have the main functions. This can result in significantly reduced manufacturing costs, ease of manufacture, and ease of control.

[0251] The following features have been described above: the processor, i.e. the control unit 9, actively controls the drive of the induction heater 8 through two temperature sensors 95 and 96. In particular, the drying load can be determined by the two temperature sensors, and the drying end time can be determined by the two temperature sensors or one temperature sensor 95.

[0252] The temperature sensors 95 and 96 are configured as thermistors and can substantially continuously output the detected temperature values. Furthermore, the output of these temperature sensors is analyzed or judged to actively determine whether to drive the induction heater 8 and execute drive control.

[0253] However, even in very small circumstances, the temperature sensor may malfunction or fail. That is, the induction heater 8 cannot be actively controlled. In such cases, it is necessary to prevent accidents and protect the washing device. Therefore, it is necessary to provide a highly reliable and safe washing device while minimizing its manufacturing costs.

[0254] Below, refer to Figure 9 The safety system of a washing apparatus according to an embodiment of the present invention will be described in detail below. For convenience, Figure 9 The word "through" is omitted in the text. Figure 2 The description covers the structure of hardware components such as the operating unit 921, sensors 95 and 96, and valve 97. Therefore, only the safety system and main control structure will be described.

[0255] Figure 9 The solid line shows wire W1 carrying a relatively high voltage and high current, while the dashed line represents control or communication line W2 carrying a relatively low current. Wire W1 can carry either AC or DC current. The AC current can be applied to motor 6 or induction heater 8, and can be converted from AC to DC current for application to processors 9a, 9b, etc. The magnitude of the current or voltage flowing through wire W1 is relatively greater than the magnitude of the current or voltage flowing through control or communication line W2.

[0256] In this embodiment, the control unit or processor 9 controls the operation of various hardware components, especially, such as Figure 9 As shown, the motor 6, which controls the drive unit, and the induction heater 8, which includes a coil, are driven.

[0257] In this embodiment, both the drive of the induction heater and the drive of the motor can be controlled by a single processor 9. However, two processors 9a and 9b can be provided to prevent overload of the processor 9 and to provide higher reliability. That is, the first processor 9a that controls the drive of the motor and the second processor 9b that controls the drive of the induction heater can be set up independently of each other.

[0258] In this embodiment, power applied to the washing device from an external power source via power supply device 200 can be transmitted to the induction heater 8 via relay 410. That is, relay 410 can be configured to switch the current flowing through the wires. When relay 410 is turned on, current flows, and when relay 410 is turned off, the current flow is cut off.

[0259] Here, the processor 9 can execute the operation of the relay 410. That is, the processor 9 can actively control the operation of the relay 410 to control the drive of the induction heater 8.

[0260] Specifically, the control unit 9 may include a first processor 9a and a second processor 9b. The first processor 9a controls the drive unit 6 and the overall operation of the washing device, while the second processor 9b controls the induction heater 8. The first processor 9a and the second processor 9b can be electrically connected and communicate with each other. In particular, the second processor 9b can control the heating of the induction heater 8 according to instructions issued from the first processor 9a. That is, the second processor 9b can not only directly control the start / stop of the induction heater but also control the output. This control can be performed by the second processor 9b by controlling the operation of a switching element 520, such as an IGBT. The first processor 9a can control the operation of the relay 410 to control whether current is applied to the switching element 520.

[0261] As a result, the driving of the induction heater can be performed in essentially three steps. First, the user presses the power button of the washing machine, thereby applying external power to the washing machine. Second, the first processor 9a controls the relay 410 to apply current to the switching element 520 that directly controls the driving of the induction heater. Third, the switching element 520 is switched on and off to control the start / stop or output amount of the induction heater.

[0262] Therefore, the relay 410 is preferably configured as normally open. That is, when the first processor does not send a control signal, the relay 410 is open, cutting off the current flow in the wire. Since no power is applied to the washing device, no control signal is generated by the first processor, and therefore the normally open relay 410 is disconnected.

[0263] The relay 410 operates for a relatively short time in the washing device. That is, the time that current flows through the relay is much shorter than the time that the current is cut off. Therefore, by setting the relay 410 to be normally open, safety accidents mainly caused by the induction heater can be prevented.

[0264] In this embodiment, a first safety device 150 can be provided to open and close the control signal applied from the processor 9, particularly from the first processor 9a, to the relay 410. The first safety device 150 is provided on the control line W2. The first safety device 150 can be configured to operate according to temperature changes.

[0265] Under normal control or active control conditions, based on the detection values ​​of the aforementioned temperature sensors 95 and 96, the first processor 9a can normally control the drive of the relay 410, or can send normal start / stop commands or output change commands to the second processor 9b for the induction heater 8.

[0266] As an example, when the upper temperature sensor 96 detects the target heating temperature, the first processor 9a can send a control signal to disconnect the relay 410. Conversely, when the upper temperature sensor 96 detects the target heating temperature, the first processor 9a can send a command to the second processor 9b to stop the operation of the induction heater 8 or reduce its output, instead of sending a control signal to the relay 410. The second processor 9b can then control the operation of the induction heater 8 or reduce its output.

[0267] Therefore, under normal conditions, the induction heater is actively driven so that heating does not occur when the temperature exceeds the target heating temperature.

[0268] However, in the event of malfunction or failure of temperature sensors 95 and 96, especially the upper temperature sensor 96, normal and active control of the induction heater 8 cannot be performed. That is, a safety accident may occur when the upper temperature sensor 96 cannot detect overheating of the roller. Furthermore, a safety accident may occur when both the roller and the induction heater 8 itself overheat.

[0269] To address these issues, according to one embodiment of the present invention, the first safety device 150 is preferably disposed on the control line between a normally open relay and a first processor. That is, when a malfunction or misoperation of the temperature sensor or similar device occurs, resulting in abnormal overheating, the device can automatically operate based on temperature changes to cut off the control signal from the first processor.

[0270] In abnormal conditions such as overheating, the first processor 9a may be unable to determine whether overheating has occurred when the temperature sensor or other components malfunction, and may therefore continue to operate the induction heater. That is, it may continuously send operating signals to the relay. In this situation, even if an operating signal is generated, the first safety device can cut off the transmission of the operating signal to the relay 410.

[0271] The interruption of the operation signal indicates that the normally open relay is disconnected. Therefore, even if the first processor commands the induction heater to be driven, the first safety device can forcibly stop the induction heater's operation.

[0272] Here, by placing the first safety device on the control line W2 instead of the wire W1, the following effects can be expected. As mentioned above, a relatively higher current flows in the wire W1 compared to the control line W2. Therefore, the specifications of the first safety device for applying or cutting off high current inevitably become higher. That is, the price of the first safety device inevitably becomes higher. Furthermore, by configuring the first safety device to apply low current instead of high current, the reliability of the first safety device itself can be further improved.

[0273] The first safety device may include multiple switching elements. These multiple switching elements are connected in series, such that cutting off any one of them will interrupt the control signal in the overall control line. Here, the switching elements may include a thermostat. Furthermore, the switching elements may include a thermal fuse. A thermostat is a switching element that operates above a set temperature and then disconnects; it can then reconnect when the temperature drops after disconnection. A thermal fuse may be a switching element that permanently operates above a set temperature and then disconnects, and will not reconnect automatically thereafter.

[0274] The installation locations and set temperatures of multiple switching elements can be different. This is to further improve reliability. As an example, one switching element can be set to detect overheating of the drum, while another switching element can be set to detect overheating of the induction heater itself.

[0275] In extremely rare cases, in addition to the inability to actively control the operation, malfunctions or errors may occur in the switching elements themselves. Therefore, by setting multiple switching elements, abnormal overheating can be prevented in advance as long as any one of them operates normally.

[0276] Below, refer to Figure 9 The embodiments are described in further detail.

[0277] A washing machine according to an embodiment of the present invention may include a power supply device or power supply circuit (PSC) 200, a heater power supply device or heater power supply circuit (HPSC) 400, a heater drive device or heater drive circuit (HDC) 500, and a drum drive device or drum drive circuit (DDC) 300.

[0278] The power supply circuit (PSC) 200 may include an input power supply 210 connected to an external power source and a noise filter 220. The external power source may be AC ​​power. The AC power applied from the input power supply 210 is applied to the heater power supply circuit (HPSC) 400 as a drive source for the induction heater 8, or to the drum drive circuit (DDC) 300 as a drive source for the motor 6. Therefore, the heater power supply circuit 400 and the drum drive circuit 300 are preferably connected in parallel with the input power supply 210. This is to ensure normal motor operation even when the induction heater 8 malfunctions. That is, to allow normal washing to be performed even when the induction heater 8 is not functioning properly.

[0279] Relay 410 is configured to switch the current applied from input power supply 210 to induction heater 8. The heater power supply circuit (HPSC) may include relay 410, noise filter 420, and SMPS (switching mode power supply).

[0280] Relay 410 is electrically connected to the first processor 9a via control line W2. Under the control of the first processor 9a, relay 410 electrically connects (or circuits) the input power supply 210 to the heater power supply circuit (HPSC) or disconnects it.

[0281] Relay 410 can be configured in various forms. As an example, it can be configured as an electromagnetic relay that uses an electromagnet to physically move contacts to open and close them. As an example, it can be configured as a leaded relay, formed by enclosing a metal lead made of ferromagnetic material within a container with an inert gas and winding a coil around it; when current flows through the coil, the lead opens and closes the contacts according to the generated magnetic field. As an example, it can be configured as a semiconductor relay (e.g., a solid-state relay (SSR)) that uses semiconductor elements such as thyristors or optocouplers to open and close a large output voltage with a small input power. However, it is not limited to the relay forms described in the examples, and other known relay forms can be implemented.

[0282] Relay 410 operates according to control commands (instructions) applied from the first processor 9a. That is, when electrically connected to the first processor 9a, relay 410 applies current output from input power supply 210 to heater power supply circuit (HPSC) according to the control commands received via control line W2.

[0283] Safety device 150 is connected to control line W2, which connects the first processor 9a and relay 410. Therefore, when safety device 150 operates and disconnects control line W2, the electrical connection between relay 410 and the first processor 9a is severed, preventing the transmission of control commands. Consequently, normally open relay 410 remains open, thus ceasing power supply from input power 210 to the heater power supply circuit (HPSC).

[0284] The roller drive circuit (DDC) may include: a rectifier 310 that converts AC through a noise filter 220 into DC; a smoothing circuit 320 that reduces pulse current included in the output voltage of the rectifier 310; an SMPS 330 that converts the current output from the smoothing circuit 320 to drive the first processor 9a; and an Intelligent Power Module (IPM) 340 that switches the current output from the smoothing circuit 320 to drive the motor 6.

[0285] The heater drive circuit (HDC) may include: a rectifier 510 that rectifies the alternating current passing through the noise filter 420; a switching element 520 that switches the current output from the rectifier 510 to be applied to the induction heater 8; and a driver 530 that drives the switching element 520 according to the control of the second processor 9b. In an embodiment, the switching element 520 is composed of an IGBT (Insulated Gate Bipolar Transistor), but is not limited thereto.

[0286] Even if the safety device 150 activates and cuts off the power to the induction heater 8, power will continue to be supplied to the drum drive circuit (DDC), so the drum 3 can still be driven normally. In particular, even if the safety device 150 includes a thermal fuse and the thermal fuse is irreversibly disconnected, the drum 3 can still be driven normally. Therefore, simple washing (or rinsing) or spin-drying can be performed until the thermal fuse is replaced.

[0287] Additionally, according to this embodiment, a safety device 160 may be included that is independently configured with the aforementioned safety device 150. For convenience, the former may be referred to as the first safety device, and the latter as the second safety device.

[0288] The aforementioned first safety device 150 can be installed on the control line W2 connecting the first processor 9a and the relay 410, and can be installed independently of the heater power supply circuit and the motor drive circuit. That is, it can be installed inside the outer barrel or the housing of the induction heater instead of on the PCB that constitutes the heater power supply circuit and the motor drive circuit.

[0289] The first safety device 150 may be a device for preventing overheating in the event that the induction heater cannot be actively controlled due to errors in the temperature sensor or control program.

[0290] However, for some reason, even under very low probability, relay 410 may fail to disconnect after being switched on. After relay 410 is switched on by an instruction from the first processor 9a, it may remain switched on even after the instruction from the first processor 9a is deactivated. That is, relay 410 itself may malfunction.

[0291] This means that even when all other structures are functioning normally, a single error—specifically, a malfunction in the relay 410 itself—could cause a failure to properly control the induction heater. While the probability of a normally open relay failing is extremely low, it is preferable to consider the likelihood of such a failure to improve reliability.

[0292] Therefore, a second safety device 160 can be provided in this embodiment. The second safety device 160 can be configured to operate according to temperature changes, so as to cut off the application of current when the temperature rises abnormally. That is, it can be set as a last resort safety device, and can be set as an irreversible thermal fuse.

[0293] The second safety device 160 is preferably located in a position that is easy to repair or replace. Furthermore, it is preferably installed on the wire W1 connecting circuits that are not among the aforementioned multiple circuits. That is, it is installed on the wire W1 connecting the input power supply 210 to the induction heater 8, preferably in a location other than the PCB constituting the power supply device, the PCB constituting the heater power supply device, and the PCB constituting the heater drive device.

[0294] As an example, the second safety device 160 can be installed on the wire W1 connecting the power supply device and the heater drive device. Of course, the second safety device 160 can be installed on the wire W1 connecting the power supply device and the heater power supply device. However, the second safety device 160 is configured to operate in the event of a malfunction or misoperation of the first safety device 150 and / or the relay 410, rather than for other reasons. Therefore, the second safety device 160 is more preferably installed on the wire connecting the power supply device and the heater drive device. Thus, when the operation of the induction heater is forcibly stopped and the second safety device is activated, the structure suspected of malfunction can be easily identified.

[0295] like Figure 9As shown, at least two wires are provided between the heater power supply device and the heater drive device. Here, the second safety device 160 is preferably located on the wire that directly applies AC power to the induction heater. When the second safety device is located on the wire supplying current to the second processor, the operation of the second processor 9b, driver 530, and IGBT 520 stops sequentially, thereby cutting off the current flow through the IGBT. However, this has the problem of requiring relatively more time and not guaranteeing the cutting off of current through the IGBT. Therefore, as an example of the second safety device 160, a thermal fuse is preferably provided on the wire connecting the noise filter 420 and the rectifier 510. Of course, the thermal fuse is more preferably installed in a location independent of each PCB, rather than on each PCB where the noise filter and rectifier are installed.

[0296] Therefore, according to this embodiment, the first safety device and the second safety device are respectively connected to other devices, wires, or control lines to provide a more reliable washing device. In particular, a washing device capable of preventing safety accidents caused by a malfunction or misoperation, such as a relay failure, can be provided.

[0297] According to one embodiment of the present invention, a washing device and a control method for the washing device are provided, which can significantly reduce the malfunction or false detection of the sensor used to detect the degree of drying due to detergent, washing water, condensate, cooling water or lint.

[0298] According to one embodiment of the present invention, a washing apparatus and a control method thereof are provided, which can detect the degree of drying using a washing water temperature sensor installed in an existing washing apparatus. That is, a washing apparatus and a control method thereof are provided, which can use a temperature sensor for other purposes according to the program executed by the washing apparatus.

[0299] According to one embodiment of the present invention, a washing device and a control method for the washing device are provided, which prevents cooling water and condensate from contacting the washing water temperature sensor during drying, so as to minimize the temperature deviation caused by cooling water, thereby enabling accurate determination of the degree of drying.

[0300] According to one embodiment of the present invention, a washing apparatus and a control method thereof are provided, which can detect the degree of drying using a drying temperature sensor provided to prevent overheating of the induction heater. That is, a washing apparatus and a control method thereof are provided that can use a single temperature sensor for multiple purposes simultaneously.

[0301] According to one embodiment of the present invention, a washing device and a control method for the washing device are provided, which can effectively determine the drying end time without having the object to be dried directly contact the sensor.

[0302] According to one embodiment of the present invention, a washing apparatus and a control method thereof are provided, which can effectively determine the drying load and the drying end time using one or two temperature sensors. In particular, a washing apparatus and a control method thereof are provided, which can effectively determine the drying load and the drying end time based on the temperature change around the condensate formed by natural convection during drying.

[0303] According to one embodiment of the present invention, a washing device is provided, wherein, under normal conditions, the processor can actively control the driving of the induction heater through a temperature sensor, and even under abnormal conditions, the driving of the induction heater can be forcibly stopped to ensure safety.

[0304] According to one embodiment of the present invention, a washing apparatus is provided in which safety is ensured by a safety device that disconnects the control connection between the relay and the processor in an abnormal state when the processor actively controls the power supply to the induction heater by controlling a relay. In particular, a washing apparatus is provided in which a first safety device, such as a thermostat or thermal fuse, is connected to a control line carrying a small current instead of a wire carrying a high current or AC current, thereby ensuring the reliability of the safety device and reducing manufacturing costs.

[0305] According to one embodiment of the present invention, a washing apparatus is provided in which a second safety device is provided independently of the first safety device, thereby preventing power from being applied to the induction heater under abnormal conditions even in the event of a malfunction or failure of the relay or the safety device. In particular, a washing apparatus is provided that further improves reliability by having a second safety device that autonomously operates based on temperature changes to directly cut off the power supply to the induction heater.

[0306] According to one embodiment of the present invention, a washing device is provided, which has multiple safety devices and the installation positions of the multiple safety devices are different, so that the safety devices can be used to more reliably execute the forced stop of the induction heater in abnormal conditions.

[0307] According to one embodiment of the present invention, a washing device is provided that can prevent safety accidents in advance in the event of a structural malfunction or failure.

[0308] Even if the effects are not described in this specification, each of the above structures of the present invention can additionally have other effects, and new effects that cannot be obtained from the prior art can be derived based on the organic combination relationship between each of the above structures.

[0309] Furthermore, the embodiments shown in the accompanying drawings may be modified and implemented in other forms, and when implemented in accordance with the structures claimed in the claims of this invention or in the equivalent scope, they shall be considered to fall within the scope of the claims of this invention.

Claims

1. A washing apparatus characterized by comprising: Comprise: an outer tub; a drum rotatably disposed in the outer tub to accommodate an object; an induction heater disposed in the outer tub to heat an outer circumferential surface of the drum opposite the induction heater; a first temperature sensor to detect a temperature of air in a space between the outer tub and the drum; a second temperature sensor to detect a temperature of washing water in the outer tub or a temperature in the vicinity of condensed water in the outer tub; and a processor to control driving of the induction heater to heat the drum to heat and dry the object based on a temperature detected by at least one temperature sensor, when the temperature detected by the first temperature sensor is greater than or equal to a first temperature, the processor controls driving of the induction heater to stop or reduce an output of the induction heater; and the processor repeatedly performs starting and stopping of the driving of the induction heater to maintain the temperature detected by the first temperature sensor at the first temperature. 2.The washing device of claim 1, wherein, during the induction heater heats washing water to perform a washing program, when the second temperature sensor detects a second temperature, the processor controls driving of the induction heater to stop or reduce an output of the induction heater. 3.The washing device of claim 2, wherein, the processor further determines a drying end time based on temperatures detected by the first temperature sensor and the second temperature sensor. 4.The washing device of claim 3, wherein, the processor further determines the drying end time based on a difference ΔT between a temperature detected by the first temperature sensor and a temperature detected by the second temperature sensor. 5.The washing device of claim 4, wherein, the processor further defines a first threshold, and stops a drying program when the difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor is greater than or equal to the first threshold; or the processor further defines a second threshold obtained by subtracting the first threshold from the first temperature, and stops the drying program when the temperature detected by the second temperature sensor is less than or equal to the second threshold. 6.The washing device of claim 5, wherein, the processor further defines the first threshold based on a drying load amount defined as a weight of a load for drying. 7.The washing device of claim 6, wherein, the processor further defines the drying load amount during the drying program after a point in time at which the first temperature sensor initially detects the first temperature in the drying program. 8.The washing device of claim 7, wherein, the processor further defines the drying load amount based on a maximum value of ΔT detected before the point in time at which the first temperature sensor initially detects the first temperature in the drying program. 9.The washing device of claim 7, wherein, ​ The processor further defines the drying load amount based on a minimum value of the ΔT detected after a point in time at which the first temperature is initially detected by the first temperature sensor in the drying course. 10.The washing device of claim 7, wherein The processor further defines the drying load amount based on a time required to reach a maximum value of the ΔT detected before a point in time at which the first temperature is initially detected by the first temperature sensor in the drying course. 11.The washing device of claim 7, wherein The processor further defines the drying load amount based on a time required to reach a minimum value of the ΔT detected after a point in time at which the first temperature is initially detected by the first temperature sensor in the drying course. 12.The washing device of claim 7, wherein The first temperature sensor is disposed at an upper portion of the outer tub and in the vicinity of the induction heater. 13.The washing device of claim 1, wherein The first temperature sensor is positioned at a location of a projection plane of the induction heater vertically protruding toward the drum. 14.The washing device of claim 1, wherein The outer tub has a condensate water containing portion having a downward recess defined at a bottom portion of the outer tub, and the condensate water is contained in the condensate water containing portion, The second temperature sensor is disposed in the vicinity of the condensate water without being in contact with the condensate water. 15.The washing device of claim 14, wherein The second temperature sensor is disposed spaced apart from a bottom surface of the condensate water containing portion by 10 mm to 15 mm. 16.The washing device of claim 1, further comprising: a power supply device supplying power from an external power source to the washing device; a relay applying or interrupting a current flow from the power supply device to the induction heater, the relay being in a normally open state so as to interrupt the current flow from the power supply device to the induction heater; the processor controls the relay by applying a control signal to the relay, the control signal causing the relay to switch from the open state to the closed state so as to apply the current flow from the power supply device to the induction heater. 17.The washing device of claim 16, wherein when the temperature detected by the first temperature sensor is equal to or greater than the first temperature, the processor stops actively sending the control signal to the relay to stop the induction heater. including:

18. A washing apparatus characterized by comprising: an outer tub; a drum rotatably disposed within the outer tub to contain an object; an induction heater disposed in the outer tub to heat a circumferential surface of the drum; a temperature sensor to detect a temperature of air in a space between the outer tub and the drum; a power supply device to supply power from an external power source to the washing device; ​ a relay electrically connected to the power supply device, applying or interrupting the current flow from the power supply device to the induction heater, the relay being in an open state, thereby interrupting the current flow from the power supply device to the induction heater; a processor controlling the relay by applying a control signal to the relay, controlling the induction heater to heat the drum to heat and dry the object based on the temperature detected by the temperature sensor; when the temperature detected by the temperature sensor is greater than or equal to a first temperature, the processor controls the relay by applying a control signal, causing the relay to switch from an on state to an off state, thereby cutting off the current flow from the power supply device to the induction heater, the processor controls the relay by applying a control signal, causing the relay to repeatedly switch between the off state and the on state, thereby applying the current flow from the power supply device to the induction heater, to maintain the temperature detected by the temperature sensor at the first temperature.

19. The washing device of claim 18, wherein when the control signal from the processor is not applied to the relay, the relay is open, thereby cutting off the current flow in the electric wire.

20. The washing device of claim 18, wherein the time during which the current flows through the relay is less than the time during which the current is cut off by the relay.

21. The washing apparatus according to claim 18, wherein Further comprising: a safety device provided in a control line between the relay and the processor, opening and closing the control signal applied from the processor to the relay.

22. The washing device of claim 21, wherein under an abnormal temperature change, even if the control signal is generated from the processor, the safety device cuts off the control signal from the processor to the relay.

23. The washing device of claim 22, wherein the safety device operates to open the control line, thereby releasing the electrical connection between the relay and the processor, and not transmitting the control signal to the relay.

24. The washing device of claim 18, wherein the processor comprises: a first processor controlling the driving of a motor that rotates the drum; and a second processor controlling the driving of the induction heater according to an instruction generated by the first processor.

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