Laundry device with induction heater and control method thereof

Abstract

The present invention relates to a laundry machine with an induction heater and a control method thereof. According to one embodiment of the present invention, a control method for a laundry machine is provided. The laundry machine includes an outer tub, a drum, an induction heater disposed outside the outer tub, and a nozzle disposed in the outer tub, and performs a steaming step. The drum accommodates an object and is rotatably disposed within the outer tub. A through-hole is formed on the outer circumferential surface of the drum. The steaming step includes: a step of rotating the drum; a heating step of driving the induction heater to heat the outer surface of the rotating drum; and a steam generating and supplying step of spraying water using the nozzle onto the outer surface of the rotating drum heated in the heating step to generate steam, wherein the steam flows into the interior of the drum through the through-hole in the drum.

Description

[0001] This invention is a divisional application of the following patent application: Application number: 201911365332.9, Application date: December 26, 2019, Invention name: Laundry device with induction heater and control method thereof Technical Field

[0002] The present invention relates to a laundry device, and more particularly to a laundry device that generates steam using an induction heater and a control method for the laundry device. Background Art

[0003] The laundry device includes an outer tub (outer tank) for storing washing water and a drum (inner tank) rotatably arranged in the outer tub. Washing (clothes) are placed inside the drum, and as the drum rotates, the clothes are washed using detergent and washing water.

[0004] To enhance the washing effect by promoting detergent activation and decomposing pollutants, high-temperature wash water is supplied to or heated within the tub. To this end, a heater mounting portion is typically formed in a downwardly recessed recess in the lower portion of the tub, and a heater is mounted within the portion. This heater is typically a sheath heater.

[0005] Recently, many laundry devices that perform washing, drying, and care using steam are provided.

[0006] During washing, steam may be supplied to the interior of the drum to increase the ambient temperature inside the drum using less energy, thereby improving washing performance.

[0007] In addition, when drying, wrinkles on clothes can be reduced by supplying steam, and the deodorizing and anti-static properties can be improved.

[0008] In addition, supplying steam to dry clothes can effectively remove dust, odor and wrinkles. In other words, it can improve the care performance.

[0009] For these reasons, not only laundry machines that perform only washing but also laundry machines that perform washing and drying and dryers that perform only drying generate steam in various forms and supply the steam to laundry.

[0010] In a laundry machine that only performs washing, a sheath heater is basically provided at the lower part of the outer tub. Washing water is heated by this heater to perform washing. This sheath heater heats water while being immersed in water.

[0011] Furthermore, in order to generate and supply steam, there is a form in which a separate steam generator is provided outside the outer drum. That is, a laundry device provided with an external steam generator is provided. In this case, there is an advantage in that high-quality steam can be freely generated in the washing and drying processes to supply the steam to the laundry inside the drum. However, there are problems in that additional devices such as a water supply unit, a heating unit, a sensing unit, a safety device, and a discharge unit as additional components may increase the material cost and limit the setting structure. In addition, the steam generated from the steam generator may condense due to cooling during the process of being transported to the inside of the drum through the connecting pipe. In view of this, it must be heated to a very high temperature. Furthermore, there is a problem in that high-temperature washing (for example, boiling washing) cannot be performed using only steam itself. This is because it is not easy to heat the washing water to a high temperature using only steam. For this reason, washing machines with external steam generators are also usually provided with a separate jacket heater for heating the washing water.

[0012] On the other hand, unlike external steam generators, a laundry machine with a built-in steam generator utilizes an existing jacketed heater to generate steam. In other words, the existing heater used to heat wash water is directly used to generate steam. This minimizes the need for additional components, resulting in significantly lower material costs. However, this approach inevitably results in wet steam, rather than high-quality steam. Furthermore, water must be supplied to fully immerse the heater before the heater is activated to generate steam, resulting in a relatively large amount of heated wash water and a consequently reduced energy efficiency. Furthermore, maintaining the heater's protective water level to prevent the heated water from coming into contact with the laundry creates a problem of limited flexibility in the timing of steam generation and supply. In particular, the need to maintain the heater's protective water level makes it difficult to generate and supply steam during drum operation, spin cycles, drying cycles, or when the circulation pump is activated. Furthermore, since steam generation and supply are difficult at the wash water level, the time available for steam generation and supply during the wash cycle is very limited.

[0013] Laundry machines with drying functions also have built-in or external steam generators. However, in these cases, an additional heater is used to generate hot air. Consequently, the system has two (heating the wash water and generating steam and hot air) or three (heating the wash water, generating steam, and generating hot air), complicating the design and inevitably the control logic. Of course, a separate duct or fan is required to achieve the drying function, inevitably increasing space constraints.

[0014] On the other hand, the present applicant proposed, through Korean patent application No. 10-2018-0123451 (hereinafter referred to as the “prior application”), that the use of an induction heater can significantly reduce the amount of washing water used compared to the use of an existing outer tub heater.

[0015] It has been proposed that the clothes can be soaked after water is supplied for washing, and the main washing can be carried out at a very low water level in the outer tub without additional water supply. In particular, it has been proposed that energy can be saved by heating the drum during the clothes soaking and main washing, and the clothes soaking and washing performance can be improved.

[0016] However, the aforementioned prior application does not disclose the steam problem. Therefore, there is a need for a laundry device that utilizes an induction heater and effectively utilizes steam while being cost-effective and safe. In particular, there is a need for a laundry device that addresses the problems associated with conventional laundry devices using steam generators. Summary of the Invention

[0017] The basic object of the present invention is to solve the problems of conventional washing machine devices.

[0018] Through one embodiment of the present invention, the purpose of the present invention is to provide a laundry device and a control method of the laundry device, which eliminates the heating source using a sheath heater and uses a heating source using an induction heater to generate steam, and can supply the steam to the laundry inside the drum.

[0019] According to one embodiment of the present invention, an object of the present invention is to provide a laundry device and a control method thereof, which can immediately generate and supply steam so as to minimize the increase in the operating time of the laundry device due to the generation and supply of steam.

[0020] According to one embodiment of the present invention, an object of the present invention is to provide a laundry device and a control method of the laundry device, which can generate steam over a large area, thereby evenly supplying steam to laundry inside a drum.

[0021] According to one embodiment of the present invention, an object of the present invention is to provide a laundry device and a control method for the laundry device, which spray water onto the outer surface of a heated drum to generate steam, thereby providing high-quality steam. Furthermore, an object of the present invention is to provide a laundry device and a control method for the laundry device, which prevent hot water other than steam from being supplied to the interior of the drum through the structure or movement of the drum.

[0022] Through one embodiment of the present invention, the purpose of the present invention is to provide a laundry device and a control method of the laundry device, which can generate steam in the space between the outer barrel and the drum and drive the drum to supply steam to the inside of the drum, thereby removing the connecting hose for supplying steam and actually performing steam generation and supply at the same time.

[0023] Through one embodiment of the present invention, the object of the present invention is to provide a laundry device and a control method of the laundry device, which can heat washing water, dry objects and generate steam through an induction heater, so that it is easy to manufacture and has a lower manufacturing cost compared with 3 heaters to 2 heaters.

[0024] According to one embodiment of the present invention, an object of the present invention is to provide a laundry machine and a control method for the laundry machine, wherein an induction heater for heating wash water and drying items is separately provided from a small induction heater for generating steam, thereby saving energy. In particular, an object of the present invention is to provide a laundry machine and a control method for the laundry machine, wherein a single inverter drive unit is used to selectively control the output of the two induction heaters.

[0025] Through one embodiment of the present invention, the object of the present invention is to provide a laundry device and a control method of the laundry device, which can separate the drum movement time and the water spraying time in the steam step in the washing program and the steam step in the drying or care program, thereby achieving optimal steam generation and supply in each program.

[0026] To achieve the above objectives, according to one embodiment of the present invention, a method for controlling a laundry machine is provided. The laundry machine comprises an outer tub, a drum, and an induction heater disposed in the outer tub, and performs a steaming step. The drum, which contains an object and is rotatably disposed within the outer tub, has through holes formed on its outer circumferential surface. The steaming step may include heating the drum, spraying water into the heated drum, and generating steam. Furthermore, the method may include supplying the generated steam into the interior of the drum.

[0027] The steaming step may specifically include: a heating step of driving the induction heater to heat the heating surface of the drum opposite to the induction heater on the outer surface of the drum; a steam generating step of spraying water onto the heating surface heated in the heating step through a nozzle; and a steam supplying step of rotating the drum so that the steam flows from the space between the outer barrel and the drum through the through-holes of the drum into the interior of the drum.

[0028] The steam step may be performed in a washing process in which water and detergent are supplied to the outer tub to wash the object.

[0029] The washing program may include: a water supply step of supplying water and detergent to the outer tub; a clothes soaking step of controlling the rotation of the drum and the driving of the circulation pump to soak the object after the water supply step; and a washing step of removing the extra water supply and controlling the rotation of the drum and the driving of the circulation pump to wash the object after the clothes soaking step is completed.

[0030] The steaming step can be performed during the washing step. That is, the steaming step can be performed during the washing step, which is the actual washing step that begins after the soaking step. After the steaming step, the washing step can end, or a subsequent washing step can be performed after the steaming step to complete the washing step. After the washing step, the washing process ends, and the rinsing and dehydration processes can then be performed.

[0031] The steam generating step may be performed after the heating step is performed for a predetermined time. The heating step may be a step of driving an induction heater, and the steam generating step may be a step of spraying water.

[0032] Preferably, the heating step is continuously performed even during the steam generating step. That is, preferably, the induction heater is driven to heat the drum even during the spraying.

[0033] The steam generation step may be repeated multiple times, that is, multiple injection processes may be performed.

[0034] The steam supply step may be performed between the steam generation step and the steam generation step. When steam is generated by spraying water, the steam supply step may be performed and then steam is generated by spraying water again. This process may be repeated in the steam generation step.

[0035] The heating step may be performed before each execution of the steam generating step.

[0036] The heating step may be continuously performed between the steam generating step and the steam generating step.

[0037] In the heating step and the steam generating step, the drum may be stopped to fix the heating surface of the drum.

[0038] In the heating step and the steam generating step, the drum is controlled to perform a swinging motion so that the heating surface of the drum expands in the circumferential direction of the drum. Preferably, the swinging motion is a motion in which the drum repeatedly reverses in the forward and reverse directions within a range of less than 180 degrees, especially within a range of less than 90 degrees.

[0039] In the steam supplying step, the drum is driven to perform a tumbling motion or a filtration motion. The tumbling motion may be a motion in which the object repeatedly rises and falls as the drum rotates at 40 to 60 RPM. The filtration motion may be a motion in which the object adheres to the inner circumference of the drum and rotates integrally with the drum as the drum rotates at 70 to 120 RPM.

[0040] The steam generation step can be performed during the wash cycle when the drum is stopped to change its rotational direction. This drum stop can also occur during wash cycles unrelated to steam. Therefore, there is no need to implement separate drum drive logic for the steam step; existing drum drive logic can be used to generate and supply steam.

[0041] The steam step may be performed in a refresh program for deodorizing and reducing wrinkles on dry objects.

[0042] In the steaming step, in the heating step, the drum is driven to perform a tumbling motion and the induction heater is driven, and after the heating step, in the steam generating step and the steam supplying step, the drum is driven to perform a filtering motion and water is sprayed.

[0043] The drum is accelerated in the tumbling motion to continuously perform the filtering motion, and the driving of the induction heater can be continuously maintained.

[0044] The steaming step may be performed at a later stage of a drying process in which the induction heater heats the drum to remove moisture from the wet object to reduce static electricity and wrinkles on the object.

[0045] In the steaming step, in the heating step, the drum is driven to perform filtering motion and the induction heater is driven, and after the heating step, in the steam generating step and the steam supplying step, the drum maintains filtering motion and sprays water.

[0046] Therefore, the movement of the drum for generating and supplying steam is preferably different depending on the program. This is because the state of the object, the purpose of the steam, and the environment inside the outer tub vary depending on the program.

[0047] To achieve the above-mentioned purpose, according to one embodiment of the present invention, in a control method of a laundry device, the laundry device has an outer barrel, a drum, and an induction heater arranged in the outer barrel to perform a steam step, the drum accommodates an object and is rotatably arranged in the outer barrel, and a through hole is formed on the outer peripheral surface of the drum, the steam step includes: a heating step of driving the induction heater to heat the heating surface of the drum opposite to the induction heater on the outer surface of the drum; a steam generating step of spraying water onto the heating surface heated in the heating step through a nozzle; and a steam supply step of rotating the drum so that the steam flows from the space between the outer barrel and the drum through the through hole of the drum into the interior of the drum, and the heating step, steam generating step, and steam supply step can be performed sequentially while the drum rotates at the same target RPM.

[0048] As an example, while the drum is driven at a tumble RPM or a filter RPM, water is first sprayed (steam generation step) while the induction heater is driven (heating step), and the steam generated while the drum is being driven can flow into the drum (steam supply step). This drum movement can be used in a care or drying program. Of course, it can also be used in a washing program. Therefore, as long as the time for spraying water is determined, the drum does not need to be moved separately for the steam step. Therefore, the control logic with steam can be simply and easily implemented from the control logic without steam.

[0049] To achieve the above-mentioned object, according to one embodiment of the present invention, there may be provided a laundry device comprising: an outer tub; a drum accommodating an object and rotatably disposed in the outer tub, wherein a through-hole is formed on an outer peripheral surface of the drum; a steam induction heater disposed at an upper front portion of a front side wall or an upper rear portion of a rear side wall of the outer tub and configured to heat a heating surface of the outer surface of the drum that is opposite to the steam induction heater; a motor that drives the motor to rotate the drum; a nozzle that sprays water onto the heating surface of the drum that is heated opposite to the induction heater on the outer surface of the drum to generate steam; and a processor that rotates the drum so that the steam flows from a space between the outer tub and the drum through the through-holes in the drum into the interior of the drum.

[0050] The drum's heating surface can be formed on the upper front portion of the drum's front sidewall, which is located above the drum's front opening. Alternatively, the drum's heating surface can be formed on the upper rear portion of the drum's rear sidewall. The position of such a heating surface can be determined by the position of the steam induction heater relative thereto.

[0051] Preferably, the drum's heating surface is formed on the upper portion of the drum's front or rear wall, on the drum's outer surface, opposite the induction heater. This is particularly important to minimize the impact of wash water or cooling water on the drum's heating surface. Furthermore, when spraying water through a nozzle, it is more preferable to spray from the top toward the bottom than from the bottom toward the top.

[0052] The steam induction heater is preferably configured to be driven for generating the steam. That is, the steam induction heater can be configured to be dedicated for steam.

[0053] In addition to the steam induction heater, a main induction heater is also included, which is arranged on the upper part of the cylindrical outer circumference of the outer barrel. The main induction heater directly heats the heating surface of the drum formed on the cylindrical outer circumference of the drum to heat the water or object inside the outer barrel.

[0054] The capacity and size of the main induction heater are preferably larger than those of the steam induction heater. Only a very small portion of the drum needs to be heated to generate steam. On the other hand, when heating the wash water and the wash objects, it is preferable to heat a wider area as possible. Therefore, the installation location may vary depending on the heating target and capacity.

[0055] Preferably, the system further comprises: a single inverter drive for controlling outputs of the steam induction heater and the main induction heater; and a switch for selectively connecting the steam induction heater and the main induction heater to the single inverter drive.

[0056] The processor may control the switch so as to selectively drive any one of the induction heater and the main induction heater through the single inverter drive section.

[0057] A water supply valve for supplying water from an external water supply source to the nozzle or a pump for supplying stored water to the nozzle may be further included.

[0058] For the purpose of annular droplet ejection, the nozzle may include: a swirler that generates a rotational velocity component in the water flowing into the nozzle; a diffusion region that extends along the length of the nozzle to expand the injection region after the swirling region; an outlet that ejects water to the outside of the nozzle after the diffusion region; and a diffuser that is arranged to surround the outlet and expand radially outward to form a spray angle.

[0059] The nozzle is preferably configured to supply water obliquely from outside the horizontal space between the opposing surfaces of the drum toward the opposing surfaces. In particular, the nozzle is preferably configured to supply water from the upper portion toward the lower portion. To this end, the induction heater is preferably disposed at the upper portion of the tub, and the nozzle is preferably mounted to the tub above the induction heater.

[0060] The processor may control the steam step of generating the steam and supplying the steam to the inside of the drum to be performed in a washing process in which water and detergent are supplied to the outer tub to wash the object.

[0061] The processor may control to execute a steaming step for generating the steam and supplying the steam to the inside of the drum in a refresh course for deodorizing and reducing wrinkles of dry objects.

[0062] The processor may control to perform a steaming step of generating the steam and supplying the steam to the inside of the drum in a late drying process of a drying process for drying the object, so as to reduce wrinkles of the object and reduce static electricity.

[0063] The washing program and the drying or care program have different conditions for the object, the purpose of the steam, and the environment inside the outer tub. Therefore, preferably, whether the drum is driven and the movement of the drum at the time of steam generation and steam supply are different in each program.

[0064] To achieve the above-mentioned object, according to one embodiment of the present invention, there may be provided a laundry device comprising: an outer tub; a drum accommodating an object and rotatably disposed in the outer tub, wherein a through-hole is formed on an outer peripheral surface of the drum; an induction heater disposed in the outer tub and configured to heat a heating surface of the outer surface of the drum that is opposite to the induction heater; a motor that drives the motor to rotate the drum; a nozzle that sprays water onto the heating surface of the drum that is heated opposite to the induction heater on the outer surface of the drum to generate steam; and a processor that rotates the drum so that the steam flows from a space between the outer tub and the drum through the through-holes in the drum into the interior of the drum.

[0065] The water supplied to the nozzle may be water supplied from an external water supply source, or may be water stored inside the laundry device. In order to supply such water to the nozzle, a water supply valve for supplying water from an external water supply source to the nozzle or a pump for supplying stored water to the nozzle may also be included.

[0066] The stored water may be water generated during washing or drying stored inside the laundry device, or may be water stored at the bottom of the outer tub.

[0067] The nozzle is preferably configured to spray annular droplets, that is, it is preferably formed to uniformly spray water in the form of droplets over a large area.

[0068] To this end, the nozzle may be formed to include a swirl region, an inner diffusion region, a spitting region, and an outer diffusion region.

[0069] Specifically, the swirling region is formed by a swirler that generates a rotational velocity component in the water flowing into the nozzle. The swirler is provided inside the nozzle to form the swirling region inside the nozzle.

[0070] The swirl region is followed by a diffusion region extending along the length of the spray nozzle to expand the spray region. The diffusion region is provided inside the nozzle and can be referred to as a region for dispersing the rotational velocity component of the water generated in the swirl region.

[0071] After the diffusion area, a discharge port is formed to spray water out of the nozzle. A portion with a reduced diameter is formed between the diffusion area and the discharge port. Therefore, the portion with a reduced diameter (the reduced diameter portion) and the discharge port can be referred to as the discharge area. The discharge area is formed inside the nozzle.

[0072] A diffuser may be provided so as to surround the discharge port and expand radially outward to form a spray angle. The diffuser is formed by an expanded pipe portion, so it can be considered that the diffusion area outside the nozzle is formed by the diffuser.

[0073] Preferably, the swirling angle of the swirler is 50 to 70 degrees, the length of the diffusion region is 4 to 8 mm, and the inner diameter of the discharge port is 3.5 to 4.5 mm. This ensures that the required spraying performance is achieved for uniformly spraying water droplets onto the target heating surface while minimizing flow resistance in the nozzle.

[0074] Preferably, the nozzle is arranged to supply water in an inclined direction from outside the vertical or horizontal space of the heating surface of the drum toward the heating surface. This is to prevent the water ejected from the nozzle from failing to reach the heating surface when the water pressure is very low.

[0075] Preferably, the nozzles are arranged to supply water from the top toward the bottom. This is to ensure that even when the water pressure drops to a certain level, water can be sprayed onto the heating surface through the nozzles. Furthermore, this is to minimize the amount of water that does not reach the heating surface and flows into the through-holes on the outer peripheral surface of the drum.

[0076] The processor can control the washing process, during which water and detergent are supplied to the outer tub to wash the object, to execute a steaming step, in which steam is generated and supplied to the interior of the drum. During the washing process, the steam can be used to increase the ambient temperature inside the drum and the outer tub. In other words, the ambient temperature can be effectively increased using relatively little energy. This can enhance the effectiveness of detergent and pollutant decomposition, thereby ensuring highly effective washing performance.

[0077] A circulation pump that pumps water in the lower portion of the outer tub and resupplies water from the upper portion to the lower portion of the inner portion of the outer tub may be provided.

[0078] The washing program may include: a water supply step of supplying water and detergent to the outer tub; a clothes soaking step of controlling the rotation of the drum and the driving of the circulation pump to soak the object after the water supply step; and a washing step (formal washing step) of removing the extra water supply after the clothes soaking step is completed, and controlling the rotation of the drum and the driving of the circulation pump to wash the object.

[0079] The processor may control so that the steam step is performed during the washing step.

[0080] The processor may control the induction heater to be driven (preheated) for a predetermined time before spraying water through the nozzle (generating steam). In other words, steam may be generated by spraying water onto the preheated heating surface. Therefore, high-quality steam may be generated.

[0081] The processor can be controlled so that the induction heater is continuously driven during the spraying period, thereby generating high-quality steam both in the early and late stages of the spraying.

[0082] The processor can control the spraying of water through the nozzle to be repeated multiple times. Specifically, a single spraying time is preset, and steam generation, i.e., spraying, can be performed multiple times to generate and supply a preset amount of steam. The longer the single spraying time, the lower the temperature of the heating surface at the end of the spraying period. Therefore, to consistently produce high-quality steam, the single spraying time is preferably between approximately 1 and 3 seconds.

[0083] Preferably, the processor controls the rotation of the drum so that the steam is supplied to the inside of the drum between the injections. That is, preferably, the drum is rotated so that the steam generated in the space between the tub and the drum is smoothly supplied to the inside of the drum.

[0084] Preferably, the processor controls the preheating process to be performed each time the jet is injected. This allows high-quality steam to be generated not only during the initial injection phase but also during the middle and later injection phases. To this end, the processor can control the induction heater to be continuously driven between injections. For example, the induction heater can be continuously driven during the steaming step, and multiple injections can be performed. For example, the induction heater can be continuously driven throughout the steaming step, and multiple injections can be performed at predetermined intervals for a predetermined period of time, before terminating the steaming step.

[0085] The processor may control the drum to stop so that the heating surface of the drum remains stationary during preheating and steam generation. Since the heating surface is stationary, the heating effect of the heating surface can be further improved. Furthermore, if water is sprayed onto the stationary heating surface, high-quality steam can be generated.

[0086] The processor may control the drum to perform a swinging motion such that the heating surface of the drum expands along the circumference of the drum during the preheating and steam generation. The swinging motion may be a motion in which the drum repeatedly reverses in a forward and reverse direction within a range of less than 180 degrees, and more preferably, reverses in a forward and reverse direction within a range of less than 90 degrees.

[0087] The heating surface can be located above the drum. Therefore, during the rocking motion, the heating surface does not come into contact with the object. Specifically, the inner surface of the drum above the heating surface does not come into contact with the object. Therefore, if the rocking motion can expand the heating surface, a larger heating surface can be effectively heated. Of course, the temperature rise will be smaller than when the heating surface is fixed.

[0088] This rocking motion also produces high-quality steam.

[0089] Preferably, the processor controls the drum to perform a tumbling motion or a filtration motion after generating the steam.

[0090] The tumbling motion may be a motion in which the object repeatedly rises and falls as the drum rotates at 40 to 60 RPM, and the filtering motion may be a motion in which the object adheres to the inner circumference of the drum and rotates integrally with the drum as the drum rotates at 70 to 120 RPM.

[0091] After generating steam, the drum rotates several times to create air flow inside the outer tub. This allows steam generated in the space between the outer tub and the drum to flow into the drum. In particular, during the filtering motion, objects cling to the through-holes on the outer surface of the drum, blocking them. Consequently, steam can pass through the through-holes, further enhancing steam supply efficiency.

[0092] Alternatively, the processor can control the steam generation during the intervals in the wash cycle when the drum is stopped to change its rotational direction. This eliminates the need for separate drum control for steam generation. In other words, the drum drive logic within the wash cycle can be used to generate steam directly. In other words, the drum drive logic does not need to include the aforementioned rocking motion or intervals in which the drum is stopped for steam generation. This simplifies the control logic and reduces the extra time spent on steam generation within the wash cycle.

[0093] The processor may control to execute a steaming step for generating the steam and supplying the steam to the inside of the drum in a refresh program (process) for deodorizing and reducing wrinkles of dry objects.

[0094] Preferably, the processor controls the drum to perform a tumbling motion and controls the induction heater to be driven, and then controls the drum to perform a filtering motion and to spray water.

[0095] Preferably, the processor controls the drum so that the drum is continuously accelerated from the tumbling motion to the filtering motion, and controls the induction heater to keep being driven continuously.

[0096] Therefore, preferably, in care program (process), the drum motion when generating steam and the drum motion when supplying steam are identical. As an example, the drum motion when generating steam remains constant, and the steam generated can be supplied to the inside of the drum.

[0097] During the care cycle, hot water (not steam) should not be directly supplied to the dry items inside the drum. To this end, it is preferable to rotate and heat the drum while spraying water onto the heated surface. Furthermore, it is preferable to continue rotating the drum after spraying water. This significantly prevents hot water (not steam) from flowing into the drum.

[0098] During the maintenance cycle, the target is drying objects, and the outer tub or drum contains very little moisture. Therefore, when the drum is heated, there is nothing to absorb significant heat. Therefore, even when the drum rotates and the heating surface is heated, the temperature of the heating surface is raised to the appropriate level for steam generation.

[0099] The processor may be controlled so as to perform a steaming step of generating the steam to supply the steam to the inside of the drum at a later stage of a drying process in which the induction heater heats the drum to remove moisture from the wet object, thereby reducing static electricity on the object and reducing wrinkles.

[0100] The processor may control to drive the induction heater and spray water during the filtering motion of the drum.

[0101] The steaming step in the drying program (process) can be the same or similar to the steaming step in the care program (process). This is because steam is supplied later in the drying process, when the moisture content of the items is approximately 15% or less, or less than 10%. During the filtering process, steam passes through the items, maximizing the wrinkle and static reduction effects.

[0102] In the above-mentioned embodiment, the induction heater can be provided on the upper portion of the cylindrical outer circumference of the outer tub, and the heating surface of the drum can be formed on the upper portion of the cylindrical outer circumference of the drum opposite to the induction heater. Such an induction heater can be provided only for generating steam. As an example, similar to the prior art, a sheathed heater can be provided to heat the washing water. However, more preferably, the induction heater is provided to directly heat the drum and heat the water or object inside the outer tub. It can be expected that the number of heaters can be reduced, and that one heater can be used to heat the washing water and generate steam. Furthermore, if an induction heater is used, not only the washing water but also the object can be heated, thereby increasing the heater function for drying.

[0103] In the above-mentioned embodiment, the induction heater can be arranged on the upper part of the front wall or the rear wall of the outer tub, and the heating surface of the drum can be formed on the front wall or the rear wall of the drum opposite to the induction heater. Such an induction heater can be provided only for generating steam. As an example, similar to the prior art, a sheath heater can be provided to heat the washing water. However, preferably, an additional main induction heater can also be provided to heat the washing water. In this case, not only the washing water but also the object can be heated, thereby increasing the heater function for drying. The main induction heater can be provided on the upper part of the cylindrical outer circumference of the outer tub independently of the induction heater. The main induction heater directly heats the heating surface of the drum formed on the cylindrical outer circumference of the drum to heat the water or object inside the outer tub.

[0104] The device may further include a single inverter drive that controls the outputs of the induction heater and the main induction heater; and a switch that selectively connects the induction heater and the main induction heater to the single inverter drive. That is, both induction heaters can be driven by selectively using a single inverter drive. The processor may control the switch so that either the induction heater or the main induction heater is selectively driven by the single inverter drive.

[0105] Thereby, manufacturing costs can be reduced and control logic can be simplified.

[0106] In order to achieve the above-mentioned purpose, according to one embodiment of the present invention, a laundry device can be provided, which includes: a box forming an outer shape; a cylindrical outer barrel, which is arranged inside the box and has a front opening; a cylindrical drum, which accommodates an object and is rotatably arranged in the outer barrel, has a plurality of through holes formed on the outer peripheral surface, and has a front opening; an induction coil, which is installed in the outer barrel and heats a heating surface of the outer surface of the drum opposite to the induction coil; a motor, which drives the motor to rotate the drum; a nozzle, which sprays water onto the heating surface of the drum to generate steam; a door, which selectively opens and closes the feeding port of the box; a gasket, which is arranged between the feeding port of the box and the front opening of the outer barrel; and a processor, which rotates the drum so that the steam flows from the space between the outer barrel and the drum through the through holes of the drum and the front opening of the drum into the interior of the drum.

[0107] When the door is closed, the space defined by the door, the gasket, and the outer tub actually forms a sealed space separated from the outside, and the drum is rotatably disposed in this sealed space. When the box loading port is opened, the front opening of the drum opens to the outside, thereby allowing the user to load or unload objects.

[0108] The steam generated in the space between the inner circumference of the outer barrel and the outer circumference of the drum, especially in the upper space having the heating surface of the drum, can flow into the interior of the drum not only through the multiple through holes arranged on the outer circumference of the drum, but also through the front opening of the drum.

[0109] In particular, during the filtering operation, one surface of an object in close contact with the inner circumference of the drum collides with steam flowing in through the through-holes, while the other surface of the object collides with steam flowing in through the front opening of the drum. As a result, steam is evenly supplied to the interior spaces of the drum and the outer tub, as well as to the object.

[0110] In order to achieve the above-mentioned purpose, according to one embodiment of the present invention, a control method for a laundry device can be provided, wherein the laundry device comprises an outer barrel, a drum, an induction heater arranged on the outside of the outer barrel, and a nozzle arranged on the outer barrel to perform a steaming step, wherein the drum accommodates an object and is rotatably arranged in the outer barrel, and a through hole is formed on the outer peripheral surface of the drum, and the steaming step comprises: a step of rotating the drum; a heating step of driving the induction heater to heat the outer surface of the rotating drum; and a steam generating and supplying step of using the nozzle to spray water onto the outer surface of the rotating drum heated in the heating step to generate steam, and the steam flows into the interior of the drum through the through hole of the drum.

[0111] The nozzles are provided to spray water in an inclined direction from an upper portion to a lower portion toward an outer surface of the drum.

[0112] The step further includes stopping the drum and the induction heater after a preset first time after the steam generating and supplying steps are completed.

[0113] It also includes a steam end judgment step for judging whether to end the steam step. In the steam end judgment step, if it is judged that the steam step is to be ended, the steam step is ended; if it is judged that the steam step is not to be ended, the steam step is executed again.

[0114] The steaming end judgment step includes: if the steaming step is executed for a preset number of times, judging that the steaming step is ended.

[0115] The steam end judgment step includes: if the temperature detected by the drying temperature sensor or the washing water temperature sensor is above a preset target temperature, judging that the steam step is ended.

[0116] The steam end judgment step includes: calculating the drying degree by the temperature difference detected by the drying temperature sensor and the washing water temperature sensor, and judging that the steam step is ended if the target drying degree is reached.

[0117] The steam generating and supplying step further includes a step of setting a water amount to be supplied through the nozzle, and the steaming end judging step includes a step of judging that the steaming step is ended if the supply of the set water amount is completed.

[0118] The steam step is performed in a drying course for drying the object or a care course for deodorizing and reducing wrinkles on the dried object.

[0119] The drying program includes: a drying step of drying the object; a step of determining whether the drying program includes the steam step; a steam step of supplying steam to the object if it is determined that the steam step is included; and an additional drying step of drying the object after the steam step.

[0120] The care program includes: a preheating step of heating the drum before generating steam; the steaming step of supplying steam to the object; a drying step of drying the object; and a cooling step of cooling the object.

[0121] In the steam generating and supplying step, the drum is driven to perform a filtering motion, wherein the filtering motion is a motion in which the object adheres to the inner circumference of the drum and rotates integrally with the drum as the drum rotates at 70 to 120 RPM.

[0122] The steaming step is performed to reduce static electricity and wrinkles on the objects at a later stage of a drying process in which the induction heater heats the drum to remove moisture from the wet objects.

[0123] In the steaming step, in the heating step, the drum is driven to perform filtering motion and the induction heater is driven, and after the heating step, in the steam generating and supplying step, the drum maintains the filtering motion and sprays water.

[0124] The induction heater is provided on the upper portion of the cylindrical outer circumference of the outer barrel, and the heating surface of the drum is formed on the upper portion of the cylindrical outer circumference of the drum opposite to the induction heater.

[0125] According to one embodiment of the present invention, a laundry device and a control method of the laundry device can be provided, which can remove the heating source through the sheath heater and use the heating source through the induction heater to generate steam and supply the steam to the laundry inside the drum.

[0126] According to an embodiment of the present invention, a laundry device and a control method thereof can be provided, which can immediately generate and supply steam so as to minimize the increase in the operating time of the laundry device due to the generation and supply of steam.

[0127] According to an embodiment of the present invention, a laundry device and a control method of the laundry device can be provided, which can generate steam over a large area and thus evenly supply steam to laundry inside a drum.

[0128] According to one embodiment of the present invention, a laundry device and a control method for the laundry device can be provided, which spray water onto the outer surface of a heated drum to generate steam, thereby providing high-quality steam. Furthermore, a laundry device and a control method for the laundry device can be provided, which prevent hot water other than steam from being supplied to the interior of the drum through the structure or movement of the drum.

[0129] Through one embodiment of the present invention, a laundry device and a control method of the laundry device can be provided, which can generate steam in the space between the outer barrel and the drum and drive the drum to supply steam to the inside of the drum, thereby removing the connecting hose for supplying steam and actually performing steam generation and supply at the same time.

[0130] According to one embodiment of the present invention, a laundry device and a control method for the laundry device can be provided, which can heat washing water, dry objects and generate steam by using an induction heater, so that it is easier to manufacture and has lower manufacturing costs compared with three to two heaters.

[0131] One embodiment of the present invention provides a laundry machine and a control method for the laundry machine, wherein an induction heater for heating wash water and drying items is separately installed from a small induction heater for generating steam, thereby saving energy. In particular, a laundry machine and a control method for the laundry machine are provided, wherein a single inverter is driven to selectively control the output of the two induction heaters.

[0132] According to one embodiment of the present invention, a laundry device and a control method for the laundry device can be provided, which can separate the time of drum movement and water spraying in the steam step in the washing program and the steam step in the drying or care program, thereby achieving optimal steam generation and supply in each program. BRIEF DESCRIPTION OF THE DRAWINGS

[0133] Figure 1 An example of a laundry machine according to an embodiment of the present invention is shown.

[0134] Figure 2 A control structure of a laundry machine according to an embodiment of the present invention is shown.

[0135] Figure 3 FIG. 2 is a graph illustrating a principle of varying the output of an induction heater using variable instantaneous power in a laundry device according to an embodiment of the present invention.

[0136] Figure 4 FIG. 1 shows the temperature distribution of the heating surface of the drum and the vicinity of the heating surface in a laundry machine according to an embodiment of the present invention.

[0137] Figure 5 The figure schematically shows a structure for generating steam in a laundry device according to an embodiment of the present invention.

[0138] Figure 6 Shown Figure 5 An example of a nozzle is shown.

[0139] Figure 7 Shown Figure 6 The relationship between the nozzle's swirl angle, diffusion area length, discharge port diameter, and diffusion angle and flow path resistance is shown.

[0140] Figure 8 Shown Figure 6The relationship between the nozzle's swirl angle, diffusion area length, discharge port diameter, and diffusion angle and the jet performance is shown.

[0141] Figure 9 The figure schematically shows a planar state of components for generating steam and a steam induction heater (coil) in a laundry device according to another embodiment of the present invention.

[0142] Figure 10 The figure schematically shows a structure for generating steam in a laundry device according to another embodiment of the present invention.

[0143] Figure 11 The structure for generating steam in a laundry device according to another embodiment of the present invention is schematically shown.

[0144] Figure 12 The figure schematically shows the connection relationship between an inverter driving unit and two induction heaters in a laundry device according to an embodiment of the present invention.

[0145] Figure 13 An example of control logic according to an embodiment of the present invention is shown.

[0146] Figure 14 Show Figure 13 An example of control logic for generating and supplying steam in a washing program (washing process) is shown.

[0147] Figure 15 Show Figure 13 An example of the control logic for generating and supplying steam in a drying program or a care program (drying process or care process) is shown.

[0148] The description of the accompanying drawings is as follows:

[0149] 1: Box 2: Outer barrel

[0150] 21: Outer barrel opening 3: Drum

[0151] 31: Drum opening 8: Heating part (induction heater, induction coil)

[0152] 95: Washing water temperature sensor 96: Drying temperature sensor

[0153] 100: Nozzle DETAILED DESCRIPTION

[0154] Below, refer to Figure 1 A laundry device according to an embodiment of the present invention is described.

[0155] In the following embodiments, for ease of explanation, certain components may be shown or described in an enlarged or reduced format. This also facilitates understanding of the present invention. Furthermore, except for steam-related features, the laundry device of this embodiment may be identical or similar to the laundry device disclosed in the aforementioned prior art patent. Of course, the control method of the laundry device may also be similar.

[0156] Therefore, the present invention is not limited to the following embodiments, and a person skilled in the art can make various modifications and variations based on this description, and such modifications and variations fall within the scope of the present invention.

[0157] A laundry machine according to one embodiment of the present invention may include: a housing 1 forming an exterior; an outer tub 2 disposed within the housing; and a drum 3 rotatably disposed within the outer tub 2 and containing objects (e.g., objects to be washed, objects to be dried, or objects to be cared for). For example, when laundry is washed with wash water, the objects may be referred to as washing objects; when wet laundry is dried with hot air, the objects may be referred to as drying objects; and when dry laundry is cared for using hot air, cold air, or steam, the objects may be referred to as cared for objects. Thus, drum 3 of the laundry machine can be used to wash, dry, or care for laundry.

[0158] The box body 1 may include a box body opening portion, which is arranged in the front of the box body 1 to allow objects to enter or be taken out. The box body 1 may include a door 12, which is rotatably installed on the box body to open and close the delivery port.

[0159] The door 12 opens and closes the box body opening, thereby opening and closing the front opening of the outer tub. Therefore, the interior of the outer tub can be considered to be sealed by closing the door.

[0160] The door 12 may include an annular door frame 121 and a perspective window 122 provided at a central portion of the door frame.

[0161] Here, in order to facilitate the detailed structure of the laundry device to be described below, a direction will be defined. Taking the center of the housing 1 as a reference, the direction toward the door 12 can be defined as the front.

[0162] In addition, the opposite direction of the direction toward the door 12 can be defined as rear (Rear), and the right (Right) and left (Left) directions can be naturally defined based on the front and rear directions defined above.

[0163] The outer barrel 2 is configured to have its longitudinal axis parallel to the bottom surface of the box or to be cylindrical with an angle of 0 to 30 degrees, and to form a space capable of storing water. An outer barrel opening 21 communicating with the inlet is provided in front of the outer barrel 2 .

[0164] The outer barrel 2 can be fixed to the bottom surface (bottom surface) of the box body 1 using a lower support part 13. The lower support part 13 includes a support rod 13a and a shock absorber 13b connected to the support rod 13a. Therefore, the vibration of the outer barrel 2 caused by the rotation of the drum 3 can be reduced.

[0165] In addition, an elastic support portion 14 fixed to the top surface of the box body 1 may be connected to the top surface of the outer tub 2 , which may also play a role in reducing vibration occurring in the outer tub 2 and transmitted to the box body 1 .

[0166] The drum 3 is configured to accommodate objects with its longitudinal axis parallel to the bottom surface (bottom surface) of the housing or in a cylindrical shape with an angle of 0 to 30 degrees. The drum 3 may have a drum opening 31 in front thereof that communicates with the outer tub opening 21. The central axes of the outer tub 2 and the drum 3 may form the same angle relative to the bottom surface.

[0167] In addition, the drum 3 may include a plurality of through holes or through-holes 33 that are provided to penetrate the outer circumference thereof, through which air and wash water can flow in and out between the interior of the drum 3 and the interior of the outer tub 2 .

[0168] The inner circumference of the drum 3 may further include lifters 35 for stirring the object when the drum rotates. The drum 3 may be rotated by a driving unit 6 provided at the rear of the outer tub 2 .

[0169] The driving unit 6 may include a stator 61 fixed to the back of the outer tub 2 ; a rotor 63 that rotates by the stator and electromagnetic action; and a rotating shaft 65 that passes through the back of the outer tub 2 and connects the drum 3 and the rotor 63 .

[0170] The stator 61 can be fixed to the rear surface of the bearing housing 66 arranged on the back of the outer barrel 2, and the rotor 63 can include a rotor magnet 632 and a rotor housing 631 arranged on the radial outside of the stator, and the rotor housing 631 connects the rotor magnet 632 and the rotating shaft 65.

[0171] A plurality of bearings 68 may be disposed in the bearing housing 66 , and the bearings 68 support the rotating shaft 65 inside the bearing housing 66 .

[0172] In addition, a star wheel 67 may be provided on the back of the drum 3 to easily transmit the rotational force of the rotor 63 to the drum 3 , and the rotation shaft 65 may be fixed to the star wheel 67 , and the rotation shaft 65 transmits the rotational power of the rotor 63 .

[0173] On the other hand, the laundry machine according to an embodiment of the present invention may further include a water supply hose 51 receiving water from the outside, and the water supply hose 51 forms a flow path for supplying water to the outer tub 2 .

[0174] In addition, a gasket 4 may be provided between the inlet of the box body 1 and the outer tub opening 21 , and the gasket 4 is used to prevent water inside the outer tub 2 from leaking into the box body 1 and to prevent vibration of the outer tub 2 from being transmitted to the box body 1 .

[0175] On the other hand, the laundry machine according to an embodiment of the present invention may further include a drain portion 52 , which is used to drain water in the outer tub 2 to the outside of the housing 1 .

[0176] The drainage portion 52 may include a drainage pipe 522 and a drainage pump 521 . The drainage pipe 522 forms a drainage path for water inside the outer tub 2 . The drainage pump 521 generates a pressure difference inside the drainage pipe 522 , thereby draining water through the drainage pipe 522 .

[0177] In more detail, the drain pipe 522 may include a first drain pipe 522a and a second drain pipe 522a, wherein the first drain pipe 522a is connected to the bottom surface of the outer barrel 2 and the drain pump 521, and one end of the second drain pipe 522a is connected to the drain pump 521 to form a flow path for moving water to the outside of the box body 1.

[0178] Furthermore, the laundry machine according to an embodiment of the present invention may further include a heating unit 8 for inductively heating the drum 3 .

[0179] The heating unit 8 is mounted on the circumferential surface of the outer tub 2 and generates a magnetic field by applying current to a wire-wound coil, thereby induction heating the circumferential surface of the drum 3. Therefore, the heating unit can be referred to as an induction heater or an induction coil. When the induction heater is activated, the outer circumference of the drum facing the induction heater 8 can be heated to a very high temperature in a very short time.

[0180] The heating unit 8 can be controlled by a control unit 9 fixed to the housing 1. The control unit 9 controls the driving of the heating unit 8, thereby controlling the temperature inside the outer tub. The control unit 9 may include a processor for controlling the driving of the laundry device, and may also include an inverter processor or inverter drive 91 for controlling the heating unit. In other words, the driving of the laundry device and the driving of the heating unit 8 can be controlled by a single processor.

[0181] However, for efficiency of control and prevention of overload of the processor, generally, a processor for controlling driving of the laundry device and a processor for controlling the heating part are separately provided and may be communicatively connected to each other.

[0182] A temperature sensor 95 may be disposed within the tub 2 and connected to the control unit 9 to transmit information about the internal temperature of the tub 2 to the control unit 9. In particular, the temperature sensor 95 may be configured to sense the temperature of the wash water or humid air. Therefore, this sensor may be referred to as a wash water temperature sensor.

[0183] The temperature sensor 95 may be disposed near the bottom of the tub. Therefore, the temperature sensor 95 may be located at a position lower than the lowermost end of the drum. Figure 1 , the temperature sensor 95 is shown to be arranged to contact the bottom surface of the outer tub. However, it is preferably arranged at a predetermined distance from the bottom surface. This is to ensure that the washing water or air surrounds the temperature sensor, so that the temperature of the washing water or air can be accurately measured. In addition, the temperature sensor 95 can be installed by passing through from the lower part to the upper part of the outer tub, but can also be installed by passing through from the front to the rear of the outer tub. That is, it can be installed by passing through the front surface (a surface forming the opening of the outer tub) rather than the circumferential surface of the outer tub.

[0184] Therefore, when the laundry device heats the washing water by the induction heater 8, the temperature sensor can be used to detect whether the washing water is heated to the target temperature. The driving of the induction heater can be controlled based on the detection result of the temperature sensor.

[0185] In addition, when all the wash water is drained, the temperature sensor 95 can detect the temperature of the air. Since there is residual wash water or cooling water at the bottom of the outer tub, the temperature sensor 95 senses the temperature of the wet air.

[0186] On the other hand, a laundry machine according to an embodiment of the present invention may include a drying temperature sensor 96. The location and temperature measurement target of drying temperature sensor 96 may differ from those of temperature sensor 95. Drying temperature sensor 96 measures the temperature of the air heated by induction heater 8, i.e., the drying temperature. Therefore, the temperature sensor can be used to detect whether the air has been heated to the target temperature. The induction heater can be controlled based on the sensing results of the drying temperature sensor.

[0187] The drying temperature sensor 96 is located on the upper portion of the tub 2 and can be positioned near the induction heater 8. Specifically, the drying temperature sensor 96 can be positioned on the inner side of the tub 2, outside the projection of the induction heater 8, and configured to measure the temperature of the outer peripheral surface of the drum 3 opposite the drying temperature sensor. The temperature sensor 95 is 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 temperature of the dry air surrounding the drum.

[0188] Since the drum 3 is configured to rotate, the outer peripheral surface temperature of the drum can be indirectly detected by detecting the temperature of the air near the outer peripheral surface of the drum 30 .

[0189] The temperature sensor 95 is provided to determine whether to continue driving the induction heater to the target temperature or whether to change the output of the induction heater. The drying temperature sensor 96 is provided to determine whether the drum is overheated. If it is determined that the drum is overheated, the driving of the induction heater can be forcibly stopped.

[0190] Furthermore, a laundry machine according to one embodiment of the present invention can have a drying function. In this case, the laundry machine according to one embodiment of the present invention can be referred to as a washer-dryer. To this end, it can further include a fan 72 for supplying air to the interior of the outer tub 2 and a duct 71 containing the fan 72. Of course, the drying function can be performed even without this additional configuration. Specifically, the air can be cooled on the inner circumference of the outer tub, and the moisture can be condensed and discharged. In other words, even without air circulation, drying can be performed by condensing moisture. To more effectively condense moisture and improve drying efficiency, cooling water can be supplied to the interior of the outer tub. The larger the surface area where the cooling water meets the outer tub, that is, the surface area where the cooling water comes into contact with the air, the better. To this end, the cooling water can be supplied by being widely distributed on the back, one side, or both sides of the outer tub. This cooling water supply allows the cooling water to flow along the inner surface of the outer tub, preventing it from flowing into the drum. Consequently, the duct or fan for drying can be omitted, making manufacturing easier.

[0191] At this time, there is no need to set an additional heater for drying. That is, drying can be performed using an induction heater 8. That is, washing water heating during washing, object heating during dehydration, and object heating during drying can be performed by one induction heater.

[0192] When the drum 3 and the induction heater 8 are driven, the entire outer circumference of the drum can actually 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 interior of the drum 3, the air that has undergone heat exchange and evaporated its moisture can be discharged outside the drum 3. In other words, air can circulate between the duct 71 and the drum 3. Of course, the fan 72 can be driven to circulate the air.

[0193] The air supply and exhaust positions can be determined so that the heated air can be evenly supplied to the drying objects and the moist air can be smoothly exhausted. To this end, the air can be supplied from the front upper portion of the drum 3 and exhausted through the rear lower portion of the drum 3, i.e., the rear lower portion of the outer tub.

[0194] Air exhausted through the lower rear portion of the tub flows along duct 71. Within duct 71, condensed water supplied via condensed water flow path 51 condenses moisture from the humid air. As moisture condenses in the humid air, it transforms into low-temperature, dry air, which then flows along duct 71 and is resupplied to the drum 3.

[0195] Because the air itself isn't directly heated, the temperature of the heated air can be lower than that of air heated in a normal dryer by a heater. This can help prevent damage or deformation of clothing caused by high temperatures. Of course, the laundry may overheat between the heated drum and the clothes.

[0196] However, as described above, by driving the induction heater along with the drum, the laundry repeatedly rises and falls (tumbling motion) as the drum is driven, and the heating position of the drum is at the top rather than the bottom, effectively preventing overheating of the laundry. Furthermore, during a rotational motion or a filtering motion in which the drum and the laundry rotate together, the drum's rotational speed is higher than that of the tumbling motion, effectively preventing overheating of the laundry. In particular, by controlling the induction heater drive only during drum rotation and repeating the drum's rotation and stopping, overheating of the laundry can be further effectively prevented.

[0197] A control panel 92 may be provided on the front or top surface of the laundry device. The control panel may be used to provide a user interface. Various user inputs may be performed and various information may be displayed. Specifically, the control panel 92 may include an operating unit for user operations and a display unit for displaying information to the user.

[0198] Figure 2 A system block diagram of a laundry device according to an embodiment of the present invention is shown.

[0199] The control unit 9 can control the driving of the heating unit, i.e., the induction heater 8, through the temperature sensor 96 and the drying temperature sensor 96. The control unit 9 can control the driving of the driving unit 6 for driving the roller, as well as the driving of various sensors and hardware through the motor. The control unit 9 can also control various valves or pumps for water supply, drainage, and cooling water supply, as well as fans.

[0200] In particular, according to this embodiment, a cooling water valve 97b may be included. The cooling water valve 97b is used to convert high-temperature, high-humidity air / environment into low-temperature, dry air / environment. The cooling water valve 97b supplies cold water to the interior of the outer tub or the interior of the pipe to cool the air, thereby condensing moisture in the air. The cooling water valve is configured to supply cooling water from an external water supply when cooling water is needed.

[0201] In addition, according to this embodiment, since washing is essential, a water supply valve 97a may be provided to supply wash water from an external water supply source to the interior of the outer tub. Normal temperature water is generally supplied to the interior of the outer tub through the water supply valve 97a, allowing washing to be performed with the wash water. Of course, a separate water supply valve for supplying hot water may be provided.

[0202] In this embodiment, a steam valve 97c for generating steam may also be provided. This valve can be considered as a valve for supplying the water required for steam generation. Similar to the water supply valve 97a, the steam valve 97c can also be configured to supply water from an external water source. Of course, it can be configured to supply both cold and hot water. However, since the water supply timing for steam and washing differs, the water supply valve 97a and steam valve 97c may be provided separately. Of course, in the case of a valve that selectively forms multiple flow paths using a single valve, such as a three-way valve, a single valve can perform the functions of both a water supply valve and a steam valve.

[0203] The water supply for generating steam can be supplied by pumping water stored inside the laundry machine rather than from an external water supply source. Therefore, in this case, it can be called a steam pump rather than a steam valve. It can be considered a structure that generates steam by supplying water through pumping.

[0204] On the other hand, in this embodiment, a circulation pump 511 may be included to resupply wash water stored in the lower portion of the outer tub from the upper portion to the lower portion of the outer tub. As described above, when washing with the induction heater, the water level inside the outer tub may be lower than the lowest end of the drum. Therefore, when the drum rotates, the lower end of the drum is not immersed in the wash water, and thus, wash water is not supplied to the drum. Therefore, the circulation pump can be driven to resupply the wash water stored in the lower portion of the outer tub to the drum.

[0205] The circulation pump 511 may be configured not only to resupply washing water but also to generate steam to supply water.

[0206] The drain pump 421 may be driven periodically or intermittently during dehydration and / or during cooling water supply.

[0207] According to this embodiment, a door lock device 98 may be included. The door lock device can be used to prevent the door from being opened during the operation of the laundry machine. According to this embodiment, the door opening is restricted not only during the operation of the laundry machine, but also after the operation of the laundry machine ends, when the internal temperature is above a set temperature.

[0208] In addition, the control unit 9 can control various display units 922 provided on the control panel 92. In addition, the control unit 9 can receive signals from various operation units 921 provided on the control panel 92 and control the driving of the entire laundry device based on the signals.

[0209] On the other hand, the control unit 9 may include a main processor for controlling the driving of a general laundry device and an auxiliary processor for controlling the driving of the induction heater. The main processor and the auxiliary processor may be independently provided and communicatively connected to each other.

[0210] According to one embodiment of the present invention, the output of the induction heater can be varied. The heating time can be reduced by maximizing the output of the induction heater within an allowable condition or range, thereby achieving optimal results. To this end, this embodiment may include an instantaneous power output unit 99.

[0211] The maximum allowable power of the laundry device can be preset. That is, the laundry device can be manufactured to be driven in a manner that the instantaneous maximum power is less than the preset power value. Figure 3 The system allowable power is represented in .

[0212] The hardware using the largest power in the laundry apparatus according to this embodiment may be considered to be the motor driving the induction heater 8 and the drum, that is, the driving unit 6 .

[0213] 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 eccentricity of the laundry. Furthermore, it can be seen that as the power used in the drive unit increases, the instantaneous power of the entire system also tends to increase. In other words, it can be seen that the majority of the instantaneous power of the entire system is consumed by the drive unit.

[0214] During the heating and dehydration process, the induction heater 8, the drive unit 6, the control panel 92, the various valves 97, the drain pump 521 and the various sensors 95 and 96 all consume power. Figure 3 As shown, when the allowable power value is determined in the laundry device system, the upper limit of the maximum total power that can be used in the laundry device can be preset in consideration of the margin.

[0215] In conventional laundry machines, the output of the jacket heater during the heating and dehydration period is preset, that is, the output of the jacket heater is preset to be less than the value obtained by subtracting the maximum power value excluding the jacket heater during the heating and dehydration period from the total power upper limit.

[0216] A brief explanation is as follows. When the allowable power value of the laundry machine system is 100 and the margin is 10, the total power limit can be 90. When the maximum power value excluding the jacket heater during the heating and dehydration period is 70, the output of the jacket heater can only be less than 20. Here, the maximum power value excluding the jacket heater can be the value obtained by adding the maximum RPM and the power value of the hardware excluding the jacket heater under the maximum laundry eccentricity environment (extreme environment).

[0217] Not only do sheath heaters themselves have very limited output variations, but when using such sheath heaters, the heater cannot be used to its full potential in normal environments rather than extreme environments.

[0218] To address this issue, the present embodiment may include an instantaneous power output unit 99. Specifically, 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 separately from the control unit 9, or a portion of the instantaneous power output unit 99 may be provided separately from the control unit or included in the control unit.

[0219] As described above, during the heating and dehydration process, the hardware that uses the most power, excluding the induction heater 8, can be referred to as the motor, i.e., the drive unit 6. Furthermore, during the heating and dehydration process, the maximum power values for the other hardware, excluding the induction heater and the drive unit, can be preset. The maximum output of the other hardware is relatively small.

[0220] Therefore, the instantaneous power output unit 99 may be configured to estimate or calculate the instantaneous power of the motor driving the drum.

[0221] As an example, the input current and DC link voltage to the motor may be detected and used to calculate the instantaneous power of the motor.

[0222] As an example, the instantaneous power of the motor may be calculated using the input current and input voltage to the motor.

[0223] As an example, the instantaneous power of the motor may be calculated using the input current input to the motor and the AC input voltage applied to the laundry device.

[0224] Therefore, the instantaneous power output unit 99 may be a unit that includes a device, element, or circuit for detecting current and voltage, and outputs the calculated instantaneous power of the motor.

[0225] If the instantaneous power of the motor is calculated, the possible output of the induction heater 8 can be calculated. That is, the value obtained by subtracting the instantaneous power calculation value of the motor and other hardware calculation values from the total power upper limit can be called the possible output of the induction heater.

[0226] Here, the instantaneous power of the motor can vary relatively widely. This is because the RPM can vary widely and the eccentricity of the laundry can be quite large. Therefore, the motor power is preferably calculated as instantaneous power, i.e., the current power. On the other hand, the maximum output of other hardware is relatively small and has a small variable range, so the maximum output can be preset to a maximum value and a fixed value can be used. Of course, the maximum output of other hardware can also be calculated as instantaneous power. However, since the output of other hardware is relatively small, it is preferable to use a fixed value for it, eliminating the need for additional devices or circuits for measuring and calculating power.

[0227] On the other hand, the instantaneous power output unit 99 can be configured to estimate or calculate the overall instantaneous power of the laundry device. As an example, the overall instantaneous power of the laundry device can be calculated using the AC input current and AC input voltage applied to the laundry device. The overall instantaneous power during the heating and dehydration period can be understood as the sum of the outputs of the induction heater, motor, and other hardware. Therefore, the difference between the overall instantaneous power and the total power upper limit represents the additional power that can be added to the output of the induction heater. As an example, if the current overall instantaneous power is 50 and the total power upper limit is 90, the induction heater can be increased by 40.

[0228] Therefore, according to this embodiment, it is possible to maximize the output of the induction heater under the current possible power state of the system. That is, when a higher power is used in the motor, the output of the heater can be reduced, and when a lower current is used in the motor, the output of the heater can be further increased.

[0229] In the above, an embodiment of heating the drum to heat the washing water and the object is described by using the heating portion, the induction heater or the induction coil 9. The induction heater 9 can be driven in a washing process for heating the washing water to wash or a drying process for heating the object to dry, thereby performing efficient washing and drying.

[0230] Below, refer to Figure 4 and Figure 5 An embodiment of a laundry machine that generates steam using the aforementioned induction heater 8 and supplies the steam to objects within a drum will be described in detail.

[0231] Figure 4 A plane diagram schematically shows a portion of the outer circumference of the drum. Figure 5 The positional relationship between the outer tub, the drum, the induction heater and the nozzle is schematically shown.

[0232] like Figure 4As shown, the induction heater or induction coil 8 can be formed into a ring, an ellipse or an orbital shape with a hollow center. In order to uniformly heat the front and back of the outer peripheral surface 32 of the cylindrical drum 3, in particular, it is preferred that the induction heater or induction coil 8 is formed into an ellipse or an orbital shape.

[0233] In accordance with the shape of the induction heater or induction coil 8, a heating surface 34 can be formed on the outer circumferential surface 32 of the cylindrical drum 30. In other words, the heating surface 34 can be formed vertically with respect to the induction heater. When current is applied to the induction coil 8, the temperature of the heating surface 34 rises more significantly than that of other parts.

[0234] Figure 4 The temperature distribution of the heating surface 34 and the vicinity of the heating surface is shown in FIG. FIG. 1 shows an example of the temperature distribution after heating with a power of about 1200 W for about 3 seconds while the drum 3 is stopped. Figure 4 In the middle, the lower part refers to the front of the drum, and the upper part refers to the back of the drum.

[0235] As shown in the figure, the temperature rise is greatest at the front-to-back center of the heating surface 34, and the temperature rise decreases as it moves away from the heating surface 34 in the circumferential direction and in the forward and backward directions. At a distance of approximately 20 mm from the heating surface 34 in the circumferential direction, the temperature rise per second can be significantly reduced to 1 / 10.

[0236] Due to the characteristics of the heating surface 34, it can be seen that a portion of the heating surface 34 can be heated to a temperature of approximately 130 to 140 degrees Celsius in a heating time of approximately 3 seconds. Therefore, it can be seen that when droplets are sprayed onto the heating surface 34, high-quality steam can be generated. However, when droplets need to be sprayed onto the heating surface 34 in a concentrated manner, it can be seen that droplets that escape the heating surface 34 cannot be converted into high-quality steam.

[0237] For this purpose, preferably, a nozzle 100 for spraying water in a droplet state is provided, and as Figure 5 As shown, the positional relationship among the outer tub 2 , the drum 3 , the induction heater 8 and the nozzle 100 is preferably determined. Figure 5 In the figure, the left side refers to the front of the outer tub, and the right side refers to the rear of the outer tub. Also, the portion shown is a portion of the upper portion of the outer tub and the drum.

[0238] If the induction heater 8 is mounted on the upper outer circumferential surface 22 of the cylindrical outer drum 2, the nozzle 100 can be located behind the induction heater 8 and mounted on the upper outer circumferential surface 22 of the cylindrical outer drum 2. Furthermore, the heating surface 34 can be formed on a portion of the upper outer circumferential surface 32 of the cylindrical drum 3, opposite the induction heater 8. Therefore, the nozzle 100 can be configured to spray droplets toward the heating surface 34 from a vertical area, i.e., a vertically projected area or space outside the heating surface 34. In other words, the nozzle 100 can be configured to spray water diagonally. Furthermore, the nozzle 100 can be configured to spray water from top to bottom.

[0239] The nozzle 100 utilizes hydraulic pressure to supply water in the form of droplets. Therefore, when water is supplied in a direction opposite to gravity, it may fall before reaching the target heating surface 34. Consequently, non-steam water may flow from the drum outer surface 32 through the through-holes 33 into the drum interior. For this reason, the nozzle 100 is preferably configured to supply water from the top to the bottom.

[0240] In order to spray water in the form of droplets toward the region of the heating surface 34 , the nozzle 100 should achieve the following objectives.

[0241] First, the pressure loss through the nozzle must be minimized. Since water pressure may fluctuate, when the pressure loss becomes large under weak water pressure, it is difficult to spray water in the desired droplet form.

[0242] In addition, the spray area should be as wide as possible. That is, the droplets should be sprayed evenly over the entire heating surface area, rather than just a part of it. This is because it can produce high-quality steam.

[0243] Figure 6 An embodiment of a nozzle 100 for achieving this purpose is shown in FIG.

[0244] The nozzle 100 may include a body 110 and a swirler 120 disposed inside the body.

[0245] The main body 110 may be formed in the form of a hollow cylindrical tube. A transition portion 112 with a reduced outer diameter may be formed at the distal end of the main body. A discharge port 113 may be formed at the distal end of the transition portion 112. Furthermore, a diffuser 114 may be formed radially outward of the discharge port 113. The diffuser may be formed in an expanded tube shape.

[0246] The cyclone 120 includes a cyclone body 121 having a funnel shape and oriented in a direction opposite to the flow of water. The interior of the cyclone body 121 is hollow, and water can flow through the cyclone body 121. Furthermore, blades 122 and 123 having a cross-shaped shape may be provided in front and rear of the outer side of the cyclone body 121, respectively.

[0247] The outer side of the cyclone body 121, that is, the area between the rear blades 122 and the front blades 123, may be referred to as a swirling area, where a rotational velocity component of water is generated. In other words, a vorticity is generated in the swirling area.

[0248] The vortex flow of the water having a rotational velocity component outside the cyclone body 121 then dissipates inside the body 110, causing the water droplets to be dispersed over a wider area.

[0249] The inventors have discovered that in order to achieve the purpose of the nozzle 100, the swirl angle, which is the angle between the radially outer end of the rear blade 122 and the center of the front blade, the diffusion length, which is the straight-line distance from the swirler to the transition portion, the inner diameter of the discharge port, and the diffusion angle of the diffuser are very important factors.

[0250] First, in order to prevent foreign matter from clogging the discharge port, the inner diameter of the discharge port should be maintained at at least 3 mm. It can be seen that preferably, clogging can be prevented at 3.5 mm to 4.5 mm and droplets can be ejected smoothly.

[0251] like Figure 7 As shown in the figure, it can be seen that the swirl angle, diffusion length, and diffusion angle have little effect on pressure loss, while the pressure loss varies significantly depending on the discharge port inner diameter. The pressure loss reaches a threshold at approximately 3 mm, so a discharge port with an inner diameter of approximately 3.5 mm to 4.5 mm, preferably 4 mm, can be formed.

[0252] like Figure 8 As shown in the figure, it can be seen that the swirl angle, diffusion length, diffusion angle and inner diameter of the discharge port all have a significant impact on the injection performance.

[0253] It can be found that, based on the threshold value of the injection performance, the injection performance gradually decreases when the swirl angle is from 60 to 30 degrees. Therefore, the swirl angle can be formed to be about 50 to 70 degrees, preferably 60 degrees.

[0254] It can be found that the spraying performance becomes increasingly better as the diffusion length increases from 1 mm to 6 mm, so the diffusion length can be formed to be about 4 mm to 8 mm, preferably 6 mm.

[0255] It can be found that the ejection performance gradually decreases as the inner diameter of the ejection port decreases from 4 mm to 2 mm. Therefore, the inner diameter of the ejection port can be formed to be 3.5 mm to 4.5 mm, preferably 4 mm.

[0256] It can be found that the spraying performance becomes increasingly better as the diffusion angle increases from 30 degrees to 45 degrees, so the diffusion angle can be formed to be 40 degrees to 50 degrees, preferably 45 degrees.

[0257] In the above description, an embodiment of a laundry machine is described in which a heating surface is formed on the outer peripheral surface of a drum, and water is sprayed toward the heating surface in the form of droplets through a nozzle to generate steam.

[0258] Hereinafter, an embodiment in which the heating surface is formed on a portion other than the outer peripheral surface of the drum will be described in detail.

[0259] like Figure 9 As shown, the induction heater 8a can be installed on the upper portion of the rear wall 24 of the outer tub. That is, it can be installed on the rear wall of the outer tub from the outside of the outer tub. Therefore, the heating surface 34 can be formed on the upper portion of the rear wall 35 of the drum 3, opposite to the induction heater 8a.

[0260] When the drum 3 is stationary, the heating surface 34 can remain fixed in a specific position. However, as the drum 3 rotates, the heating surface 34 continuously changes. Therefore, this embodiment is identical to the above-described embodiment, differing only in the installation position of the induction heater 8a. Therefore, it can be considered that only the position of the drum's heating surface 34, as well as the nozzle's position and spray direction, differ.

[0261] On the other hand, the induction heater 8a in this embodiment is not intended to heat wash water or objects. In other words, it can be considered to be provided primarily for steam generation. This differs from the above-mentioned embodiment. Furthermore, since it does not need to heat wash water or objects, the induction heater 8a in this embodiment is preferably formed in a circular shape. The nozzle 100 in this embodiment can be used in the same manner as the above-mentioned embodiment, and may differ only in its location and spray direction.

[0262] Although not in Figure 9 , but can be provided independently of the induction heater 8a for generating steam Figure 5 The induction heater 8 is shown. That is, two induction heaters may be provided so that one performs drum heating to heat the wash water and the object and the other performs drum heating to generate steam.

[0263] Reference Figure 10 Another embodiment according to the present invention will be described.

[0264] In this embodiment, the position of the induction heater 8a may differ from that of the above-described embodiment. Specifically, the induction heater 8a may be positioned in front of the upper portion of the front sidewall 23 of the outer tub 2. The heating surface 34 may be formed on the upper portion of the front sidewall 36 of the drum 3, opposite the induction heater 8a. The nozzle 100 may be positioned above the induction heater 8a. Specifically, it may be mounted from the upper portion of the induction heater 8a to the front sidewall 23 of the outer tub. The steam valve 97c may be located at the rear of the laundry machine, so that water can be supplied to the nozzle 100 by being guided from the steam valve 97c via the connecting hose 13. The nozzle 100 sprays water in the form of droplets from the upper portion to the lower portion and in an oblique direction. Specifically, the water is sprayed toward the heating surface 34.

[0265] Although not in Figure 10 , but can be provided independently of the induction heater 8a for generating steam Figure 5 The induction heater 8 is shown. That is, two induction heaters may be provided so that one performs drum heating to heat the wash water and the object and the other performs drum heating to generate steam.

[0266] Reference Figure 11 Another embodiment according to the present invention will be described.

[0267] This embodiment can be used with Figure 9 The embodiment shown is the same. However, instead of using an external water supply source to supply water to the nozzle, a steam pump 97c, 511 can be used to supply water to the nozzle.

[0268] As described above, the laundry machine according to one embodiment of the present invention can be configured to resupply water stored in the lower portion of the outer tub from the upper portion of the inner side of the outer tub to the lower portion. Specifically, the resupply can be achieved by pumping water via a circulation pump 511. The water pumped by the circulation pump 511 can be sprayed toward the heating surface 34 located on the upper portion of the rear wall 35 of the drum. A connecting hose 130 can be provided between the circulation pump 511 and the nozzle 100 to supply the water in the lower portion of the outer tub to the nozzle.

[0269] Although not shown in the figure, a flow path switching valve may be provided in the connecting hose 130. That is, the connecting hose may branch when spraying water onto the heating surface and when supplying water directly into the drum, and the position where water is ejected may be changed by the flow path switching valve.

[0270] On the other hand, unlike the circulation pump 511, the steam pump 97c may also pump water stored in a separate space outside the interior of the outer tub.

[0271] Although not in Figure 11 , but may be provided separately from the induction heater 8a for generating steam Figure 5The induction heater 8 is shown. That is, two induction heaters may be provided so that one performs drum heating to heat the wash water and the object and the other performs drum heating to generate steam.

[0272] Figure 12 The concept of controlling the output of the induction heaters by one inverter drive 91 when two induction heaters 8 and 8 a are provided is schematically shown.

[0273] One induction heater 8 heats the outer surface of the drum to heat the wash water or objects. The induction heater 8 can be operated during either the washing or drying cycle. Another induction heater 8a heats the front or rear sidewall of the drum to generate steam. The induction heater 8a can be operated to generate steam during either the washing, drying, or conditioning cycles.

[0274] When two induction heaters 8 are provided, their purposes differ. Simultaneous operation of both heaters is necessarily avoided in terms of power consumption. However, due to their different purposes, the likelihood of simultaneous operation is low. Therefore, it is preferable to control the output of both heaters using a single inverter drive unit 91. This reduces manufacturing costs compared to providing separate inverter drive units.

[0275] Specifically, a single inverter drive unit 91 is connected to the induction heater 8 (which may be referred to as a main induction heater) via a first connection 91b, and may be connected to the induction heater 8a (which may be referred to as a steam induction heater) via a second connection 91c. A switch 91a may be provided to selectively connect either the main induction heater or the steam induction heater to the inverter drive unit 91.

[0276] Because the main induction heater may require a higher drive ratio, frequency, or duration than the steam induction heater, the switch is configured to connect the main induction heater to the inverter drive unit. Furthermore, the switch position can be changed to connect the steam induction heater to the inverter drive unit to generate steam. This switch operation can be performed by the processor 9. This is because the processor 9 controls the entire laundry machine's operation and can determine when to activate the main induction heater or the steam induction heater.

[0277] Various embodiments have been described above, centering on a configuration in which steam is generated by an induction heater. Examples include an embodiment in which steam is generated by a main induction heater for heating wash water or a drum, an embodiment in which steam is generated by a steam induction heater solely for generating steam, and an embodiment in which two induction heaters are provided.

[0278] Below, refer to Figure 13A control method for a laundry machine according to an embodiment of the present invention will be described in detail.

[0279] In laundry machines, steam can be used in a washing cycle, which uses wash water and detergent to wash items. Steam can also be used in a drying cycle, which heats wet items and dries them. In particular, steam can be supplied in the latter stages of the drying cycle to control moisture content. This can be expected to reduce static electricity. Steam can also be used in a care cycle, which supplies steam to dry items to remove odors and reduce wrinkles.

[0280] Here, the washing, drying, and care programs may form a single process within the laundry device, or may be sub-processes within a single process. In a laundry device, a process refers to a process in which multiple programs are automatically and sequentially executed and completed. For example, a washing process refers to a washing, rinsing, and spin cycle that are automatically and sequentially executed. Such a washing process may also additionally include a drying or care program.

[0281] The drying process may include only a drying process for heating the object, or may include a cooling process for cooling the object after the drying process.

[0282] The care course may include only a care program for supplying steam to the object, and may include a drying program and / or a cooling program for drying the object after the care program.

[0283] The laundry device according to this embodiment can include a washing process using steam, a drying process using steam, and a care process using steam, and these processes are executed as one process. In addition, the laundry device according to this embodiment can use steam in the washing process, the drying process, and the care process executed in one process.

[0284] The purpose of using steam for washing, drying, and care may be different. In addition, the state of the object at the time of steam supply may also be different. For this reason, it is preferred that the driving control of the induction heater and the driving control of the drum are different when generating steam and supplying steam.

[0285] The following describes methods for controlling the use of steam for each of the washing, drying, and conditioning processes. As mentioned above, drying and conditioning can also be included in the washing process. Of course, a laundry machine can be configured to perform all of these processes, or it can also perform only one of them.

[0286] When the user selects a specific course through the user interface, the processor detects the course (S10) and controls the laundry device to perform the corresponding course.

[0287] When a washing process is selected, water is supplied (S11) and washing begins. Before water is supplied, the drum may be driven to distribute the laundry, detect the amount of laundry, or detect the amount of cloth. During and after water supply, the drum may be driven to distribute the laundry, detect the amount of laundry, or detect the amount of cloth.

[0288] After water is supplied (S11), the drum may be driven and the circulation pump 511 may be driven to perform soaking of the laundry. During soaking of the laundry, the objects are sufficiently wetted and the detergent is dissolved.

[0289] After the clothes have been soaked, steam washing (S14) or normal washing (S15) can be performed. Normal washing is washing performed without steam. After the clothes have been soaked, steam washing or normal washing can be performed without additional water supply to the inner part of the outer tub. During steam washing and normal washing, the induction heater 8 can be driven as needed to heat the wash water. This is different from steam.

[0290] After soaking the clothes, the water level in the outer tub is lower than the lowest part of the drum. Therefore, even if the drum rotates, wash water is not supplied to the interior of the drum. However, circulation pump 511 is activated, and wash water and detergent water are supplied to the items in the drum, performing the washing process. Since a smaller amount of wash water is used, energy used for heating the wash water can be saved, and the amount of water used can be reduced. Furthermore, using highly concentrated detergent water for washing improves washing efficiency.

[0291] The judgment (S13) as to whether to perform steam washing (S14) or normal washing (S15) may be made after soaking the laundry, but may also be made (determined) in the process determination step (S10) which is an initial stage of performing washing.

[0292] During steam washing or normal washing, the washing water can be heated during the tumbling motion, filtering motion, or filtering motion of the drum continuously after the tumbling motion. At this time, the driving of the circulation pump can be synchronized with the driving of the drum. Moreover, the driving of the drum and the driving of the induction heater 8 can also be linked. That is, the induction heater 8 can only be operated when the drum is rotating. However, in the early and late stages of the rotation of the drum, the driving of the induction heater 8 can be limited to prevent overheating of the object. As an example, when the drum is accelerated to above 20RPM, the induction heater 8 can be driven, and when the drum is decelerated to below 20RPM again, the driving of the induction heater 8 can be stopped.

[0293] Here, the tumbling motion may be a motion in which the object repeatedly rises and falls inside the drum as the drum rotates at about 40 to 60 RPM. Furthermore, the filtering motion may be a motion in which the drum and the object rotate integrally as the drum rotates at about 70 to 120 RPM, preferably 80 to 100 RPM.

[0294] The filtering motion is the motion of the object in close contact with the inner surface of the drum, thereby using centrifugal force to drain the washing water from the object. Therefore, the filtering motion can prevent the circulation pump from malfunctioning due to a small amount of washing water.

[0295] On the other hand, the induction drive control and drum rotation control can be different in the steam step of the washing program and the wash water heating step of the washing program. In addition, water must be sprayed through the nozzle to generate steam. The steam step of the washing program will be explained in detail later.

[0296] When steam washing (S14) or normal washing (S15) is completed, washing is completed by a rinsing cycle (S16) and a spin cycle (S17). It is then determined whether a drying cycle has been selected after washing (S18). If not, the process ends. If selected, a drying cycle (S19) is performed to dry the washed items. After the drying cycle (S19), a cooling cycle (S20) is performed, if necessary, to end the process.

[0297] On the other hand, the steam step in the drying program can be different from the wash water heating step and the steam step in the washing program in terms of the induction heater and drum rotation control. The steam step in the drying program will be described in detail later.

[0298] If the drying process or the drying program is selected in the process determination step (S10), the drying process or the drying program is executed (S21). It is determined whether the drying program includes a steaming step (S22). If the steaming step is not included, a cooling process (S25) is executed after the drying process if necessary, and the process can be ended.

[0299] If the drying process includes a steaming step, the steaming step (S23) is performed after the drying process (S21). The steaming step (S23) can be performed later in the drying process and applies steam to the object to reduce static electricity and wrinkles. The drying process can be performed in the same manner as a normal drying process without the steaming step until the moisture content is approximately 10% or above. When the moisture content is approximately 10% to 5%, steam is applied to prevent the object from getting wet, prevent static electricity, and reduce dry wrinkles.

[0300] Thereafter, drying (S24) is additionally performed, and a cooling process (S25) may be performed if necessary to complete the process.

[0301] The drying cycle can be considered a process where the induction heater heats the drum, thereby heating the object. The dehydration cycle removes as much water as possible from the tub and any water absorbed by the object. Therefore, the drum rotation control during the drying cycle differs from that during the wash water heating cycle. Of course, the induction heater can be activated only during the drum operation, and the activation threshold RPM for the induction heater can be the same as during the wash cycle.

[0302] The drum movement during the drying process can vary depending on the type and weight of the object. Specifically, it can vary depending on the drying load conditions. This is believed to be due to the fact that effective drying requires contact between the drum heated by the induction heater and the load.

[0303] Since a large number of general loads are entangled with each other, it is difficult to disperse or rearrange the clothes during the tumbling motion. In addition, the posture of the clothes usually does not change during the tumbling motion. In the case of left-right reversal, the posture of the clothes does not change, and the rise and fall are repeated. In this case, the clothes fall before their upper parts come into contact with the upper part of the inner circumference of the drum. In addition, the lower part of the clothes contacts the lower part of the inner circumference of the drum, which has a lowered temperature, or the contact is restricted by other clothes. Therefore, during the left-right reversal and tumbling motion of the drum, only the two sides of the clothes and the inner circumference of the drum are heated and dried, and there is a high possibility that the upper and lower parts are under-dried.

[0304] Therefore, for large capacity loads, together with a large amount of general loads, it is preferred to perform filtering motion or space ensuring motion at 90 to 110 RPM so that the load is close to the drum inner peripheral surface. Of course, the drum rotation and the drive of the induction heater can be linked.

[0305] When the load is pressed against the inner circumference of the drum due to centrifugal force, space can be ensured in the central part of the drum. If the space ensuring movement is stopped and the drum stops, the load falls into the empty space due to gravity. As a result, the load may be rearranged, dispersed, and changed in posture. After the space ensuring movement is completed, the rolling movement can be performed. In addition, the space ensuring movement and the rolling movement can be performed for about 20-30 seconds. Drying can be performed by performing a drum movement cycle consisting of one space ensuring movement and two rolling movements. A drum stop time of about 2 to 4 seconds can be set between the space ensuring movement and the rolling movement and between the rolling movement and the rolling movement. Since the load needs to fall between the space ensuring movement and the rolling movement, it is more preferred that the drum stop time during this period is longer than the drum stop time between the rolling movement and the rolling movement.

[0306] Because a large load (such as bedding or down jackets) fills the drum, it tends to rotate integrally with the drum even during tumbling. In this case, only a portion of the bedding load (the portion in contact with the drum's inner circumference) is heated, while the portion toward the center of the drum remains unheated. Consequently, some portions of the bedding are likely to be over-dried and others under-dried.

[0307] Furthermore, a large load may fill the interior of the drum from the moment it is placed there, creating an eccentricity that is difficult to eliminate. Therefore, when accelerating with the aforementioned space ensuring movement, the eccentricity is likely to cause vibration and may make it difficult to smoothly enter the space ensuring movement.

[0308] Therefore, in this case, a tumbling acceleration motion with a lower RPM than the space-securing motion can be performed to bring the load into close contact with the inner circumference of the drum to a certain extent, and then further secure the central space of the drum through the space-securing motion. Then, the load can be rearranged, distributed, and changed in position through the tumbling motion.

[0309] The RPM of the tumbling acceleration motion is between the tumbling motion and the space securing motion. The tumbling acceleration motion may have an RPM of approximately 70 to 80. On the other hand, the tumbling acceleration motion preferably first accelerates to the tumbling RPM while maintaining the speed, then further accelerates while maintaining the acceleration, rather than accelerating to 70 to 80 RPM from the start while maintaining the speed. A primary target RPM of approximately 60 RPM may be used, and after a predetermined time, a secondary target RPM of approximately 80 RPM may be used, and the drum may be rotated at the predetermined time.

[0310] Furthermore, during the tumbling acceleration motion, the object also rotates integrally with the drum. Therefore, since the object and the drum are in constant contact at a moderate RPM, heating is effective. Furthermore, the spatially secured motion facilitates heating even inside thick objects. The tumbling motion then allows for load rearrangement and position changes, resulting in uniform heating of the object.

[0311] After the overturning acceleration motion is repeated for a plurality of times to perform forward and reverse rotation, the space ensuring motion and the rolling motion can be performed. The overturning acceleration motion, the space ensuring motion and the rolling motion can be repeatedly performed in sequence to form a roller motion cycle.

[0312] Therefore, large loads (such as bedding loads or down jacket loads, etc.) are preferably dried by this drum motion cycle.

[0313] Most damage to items (e.g., shrinkage or deformation caused by drying) is thought to be caused by friction or mechanical forces between items. This accounts for approximately 80% of damage. While this is unlikely with normal loads, it can be a significant problem with delicate items.

[0314] For delicate garments, such as those with a delicate texture, centrifugal force exerts a pull on the garments when the drum rotates at high RPM, potentially applying mechanical forces to the garments. Furthermore, during the tumbling motion, friction or entanglement between garments is likely to generate pull. Therefore, for delicate garments, it is preferable to prioritize the aforementioned tumbling acceleration motion, supplemented by the tumbling motion for distributing, rearranging, and changing the garment's position.

[0315] Multiple tumbling acceleration movements can be driven in a forward and reverse rotational manner, followed by a tumbling movement with fewer cycles. For example, the tumbling acceleration movement can be performed with five forward and reverse rotations, and the tumbling movement can be performed with two forward and reverse rotations. This tumbling acceleration movement and tumbling movement can form a drum motion cycle. Therefore, for example, for delicate clothing loads, it is preferable to perform drying with a drum motion cycle consisting of tumbling acceleration and tumbling.

[0316] On the other hand, the drying load condition can be determined or judged at various moments, such as by detecting the amount of laundry during a wash cycle, detecting the amount of wet laundry after water supply, a user-selected process, detecting the amount of laundry during a drying cycle, etc. Of course, the drying load condition can also be determined by comprehensively considering factors derived or input at various moments.

[0317] In the above embodiment, the continuous rotation time of the drum is preferably less than 1 minute, and the drum preferably rotates in one direction for about 20 to 30 seconds. Moreover, the rotation direction is preferably changed after the drum stops moving.

[0318] If the drum stops rotating, the driving of the induction heater also stops. Therefore, it is possible to prevent the possibility of overheating of a specific load due to continuous driving of the induction heater when the drum rotates for a long time.

[0319] When a care process or care program is selected in the process determination step (S10), the care process or care program is executed (S26). The steaming step may be executed by default in the care program. To maximize the effect of the high-temperature steam, a preheating step (S26) of the heating drum is preferably performed before steam generation. Of course, this preheating step may be omitted as desired.

[0320] The steaming step (S27) can be the same as the steaming step in the drying process. When the steaming step is finished, the process can be ended by drying (S28) and cooling (S29).

[0321] The care process can be considered a process performed on a small amount of dry laundry. Specifically, it can be considered a process performed on two to three pieces of clothing, such as shirts. Therefore, the drum motion in the preheating step (S26) is preferably a tumbling motion. Furthermore, the steaming step in the care process can be the same as the steaming step in the drying process (drying program). This will be explained in detail later.

[0322] Below, refer to Figure 14 Detailed description of the steam step in the wash program.

[0323] In the washing process, the temperature of the drum may be lower than that of the drying process due to the wet objects and the washing water. Therefore, the processor preferably controls to generate steam by spraying water through the nozzle after preheating the drum.

[0324] First, the induction heaters 8, 8a are driven to preheat the drum, and then water is sprayed toward the heating surface of the drum (S144) to generate steam. Preferably, the water is sprayed after about 2-3 seconds (S143) have passed since the induction heaters were driven.

[0325] On the other hand, as mentioned above, the temperature rise during drum heating in a washing cycle is smaller than during drying. When the drum is heated during rotation, the heating surface of the drum moves circumferentially. Consequently, the heating surface is not sufficiently heated, making it difficult to produce high-quality steam.

[0326] For this reason, it is preferred that the induction heater be driven during the steam step of the wash cycle while the drum is stationary or in a rocking motion. When the drum is stationary, the heating surface is fixed. Therefore, the heating surface can be heated quickly. Rocking motion of the drum involves repeated forward and reverse rotation of the drum within a range of less than 180 degrees left or right. Therefore, the RPM is low and the amplitude of the heating surface changes only slightly, allowing the heating surface to be relatively expanded. The surface heating of the heating surface can heat the outer air layer adjacent to the heating surface.

[0327] The nozzle 100 sprays water toward the outer peripheral surface of the drum and the heating surface of the drum provided on the outer surface of the front side wall of the drum or the outer surface of the rear side wall of the drum. Therefore, the water reaches the surface of the heating surface and turns into steam, which is located in the space between the outer tub and the drum.

[0328] This steam needs to be supplied to the interior of the drum to provide moisture and heat to the object. Therefore, after generating steam, the processor 9 needs to drive the drum (S145) so that the steam flows into the drum through the through holes 33 or the drum front opening 31. Therefore, the drum driving movement before and after steam generation is preferably different.

[0329] This steam step can be performed multiple times. The number of times the steam step is performed can be determined by time factors or temperature factors.

[0330] The main purpose of the steam in the washing process is to heat the object and the air between the outer tub and the drum. That is, its purpose is to supply high-temperature steam to the surrounding air to quickly increase the temperature of the surrounding air.

[0331] Therefore, the steaming step may be repeated until the temperature inside the outer tub rises to the target temperature via the drying temperature sensor 96. On the other hand, if the steaming step is additionally performed after the washing water is heated, the steaming step may cause the temperature of the washing water to rise. Therefore, the steaming step may be repeated until the temperature of the washing water rises to the target temperature via the washing water temperature sensor 95.

[0332] The time factor can be used together with this temperature factor or alone. The steam step can be repeated for a preset time.

[0333] Generating steam multiple times means performing water injection multiple times. Therefore, preferably, during the multiple water injections, the preheating is performed each time. Moreover, the induction heater can be continuously driven between injections.

[0334] On the other hand, when the drum stops or performs a rocking motion to perform the steam step, the washing time may be increased. This is because if the time for providing mechanical force by the drum drive is set, the increase in the time the drum is stopped midway means an increase in the overall washing time.

[0335] Therefore, the induction heater can be driven and water sprayed during the steaming step while the drum is stopped for the reverse rotation direction, rather than when the drum is specifically stopped. Specifically, the induction heater can be driven and water sprayed for approximately 3 to 5 seconds after the drum has been rotating in the forward direction and is stopped for the reverse rotation direction. If steam is generated after the water spraying, the drum can be rotated again, smoothly supplying the generated steam to the interior of the drum.

[0336] On the other hand, when the drum begins rotating after stopping, it can temporarily perform a rocking motion. To rotate in one direction, it can be rotated in the other direction by a predetermined angle before continuing to rotate in the other direction. Therefore, the induction heater can be driven before the drum stops rotating in one direction, and after performing the rocking motion in one direction, the drum can be rotated in the other direction. Therefore, the induction heater can be driven before the drum stops, and water can be sprayed before the drum stops and begins the rocking motion.

[0337] Therefore, the preheating of the induction heater can be performed using the drum movement and the stop moment or swing moment between the drum movement, thereby generating and supplying high-quality steam and preventing the increase of washing time.

[0338] The steam quality (high temperature and low density) in the washing program may have a relatively small impact on the washing effect. In other words, the steam quality required for the washing program may be lower than that for the drying program and the care program.

[0339] Therefore, water can be injected while the drum and the induction heater are both being driven. Since the drum's heating surface is not stopped, its temperature may be relatively low, thus reducing steam quality. However, this approach offers the advantage of allowing steam to be generated at any time during the wash cycle, as long as the drum is rotating. Essentially, water injection can be performed at the appropriate time within the wash cycle algorithm. Consequently, the control algorithm can be very simple.

[0340] Furthermore, as described above, in a laundry machine that heats wash water using an induction heater, the circulation pump is driven during the wash cycle. Therefore, a portion of the circulation pump's activation times can be replaced by nozzle operation, rather than the circulation pump. This also offers the advantage of alternately heating the wash water and heating the surrounding air using steam.

[0341] In the following, reference is made to Figure 15 The steam steps S23 and S27 in the drying process (program) or the care process (program) are described in detail.

[0342] As mentioned above, the drum temperature may rise even higher when the induction heater is activated during the drying or conditioning cycle. Furthermore, in the drying cycle, since the steaming step occurs later in the drying process, most of the steam is supplied to the drying object. Furthermore, the conditioning cycle targets the drying object. Therefore, when steam generation is required, the drum temperature rise will inevitably be greater when the induction heater is activated. This is because most of the heat-absorbing moisture is removed.

[0343] Therefore, in the steam step of the drying process or the care process, water may be sprayed to generate steam (S33) while the drum is driven (S231) and the induction heater is driven (S232). Furthermore, even after the steam is generated, the induction heater and the drum may be continuously driven, and after a predetermined time has passed, the driving of the drum and the induction heater may be stopped (S234).

[0344] That is, during the drying or care process, steam generation and steam supply can be performed simultaneously. Therefore, there is no need to perform additional drum drive control for steam generation. In other words, it is only necessary to determine the timing of water spraying in the control algorithm of the basic drying or care program.

[0345] This steaming step can be repeated. The water spraying step can be repeated while the drum and induction heater are continuously driven. However, as mentioned above, it is not desirable to continuously drive the drum and induction heater for more than one minute. This is because overheating may occur in objects in contact with the inner circumference of the drum.

[0346] Therefore, the driving of the drum and the induction heater may be performed for approximately 20 to 30 seconds, water may be sprayed to generate steam at approximately 13 to 23 seconds, and the steam may flow into the inside of the drum.

[0347] In particular, when generating steam, the drum motion is preferably a filtering motion. This allows the steam to pass through the unfolded load, thereby improving wrinkle removal and deodorization performance. Consequently, steam is preferably generated during the aforementioned tumbling acceleration motion or space-enhancing motion, and supplied to the object.

[0348] The steaming step can be terminated after being executed multiple times. The steaming termination determination (S235) can be similar to the washing process, using temperature or time factors. The steaming step can be repeated until the target temperature is reached by the drying temperature sensor 96 or the wash water temperature sensor 95. Alternatively, the drying degree can be calculated based on the temperature difference detected by the drying temperature sensor 96 and the wash water temperature sensor 95, and the steaming step can be terminated when the target drying degree is reached.

[0349] A predetermined amount of steam can be generated by supplying a predetermined amount of water. The predetermined amount of water can be supplied based on water pressure and supply time. Therefore, a time factor can be used to determine the end of the steaming step. When treating a small number of objects, a predetermined amount of water can be supplied within a predetermined time to deliver a predetermined amount of steam to the object. This eliminates the need for complex determination of the end time of the steaming step.

[0350] In the above embodiment, a single induction heater 8 can be used to heat the wash water, heat the drying object, and heat the steam. This means that three heaters are replaced with one. This reduces manufacturing costs, simplifies manufacturing, and simplifies control logic.

[0351] On the other hand, when using a single induction heater 8, it heats the outer circumference of the drum. Therefore, the size of the induction heater increases in order to heat a large area of the drum. Therefore, operating this induction heater 8 may waste energy when heating a small amount and a small area to generate steam. Furthermore, since water is sprayed onto the outer circumference of the drum to generate steam, hot water may be supplied through the through-holes to objects inside the drum during a non-washing or drying cycle. This problem can be solved by appropriately designing the spray area or spray angle of the nozzle, but it is difficult to address the fundamental problem caused by water pressure deviation. Fortunately, during a drying or a conditioning cycle, water can be sprayed to generate steam while the induction heater 8 and the drum are being driven. Since the drum is not stationary but rotates at a relatively high speed, even if water contacts the outer circumference of the drum, it is dispersed to the inner circumference of the outer tub due to the rotation of the drum, significantly reducing the possibility of hot water flowing into the drum.

[0352] When two induction heaters 8, 8a are used, one induction heater 8a can be used solely for steam. In this case, the steam induction heater 8a can be located in front of the upper portion of the front sidewall or behind the upper portion of the rear sidewall of the outer tub. The opposing surface of the drum, which faces the steam induction heater 8a, is also formed in front of the upper portion of the front sidewall or in front of the upper portion of the rear sidewall. These front and rear sidewall portions of the drum do not include through-holes, or the number of through-holes is very small. Therefore, the sprayed water cannot be vaporized and converted into hot water, significantly reducing the amount of sprayed water flowing into the drum.

[0353] In addition, since a small-capacity steam induction heater 8a can be used instead of a large-capacity main induction heater 8 when generating steam, energy can be saved.

[0354] On the other hand, in the above-described embodiment, the heating surface of the drum is formed on its outer surface, and water is sprayed onto the outer surface of the drum. Specifically, the water is sprayed into the space between the outer tub and the drum, generating steam there. This prevents the sprayed water from flowing directly into the drum, and the steam easily moves circumferentially and radially within the relatively narrow space between the outer tub and the drum. In other words, steam can flow evenly into the drum along its circumference.

Claims

1. A method for controlling a laundry machine, wherein the laundry machine comprises an outer tub, a drum, an induction heater disposed outside the outer tub, and a nozzle disposed in the outer tub to perform a steaming step, wherein the drum accommodates an object and is rotatably disposed in the outer tub, and a through hole is formed on the outer circumference of the drum, wherein: The steam step comprises: a step of rotating the drum; a heating step of driving the induction heater to heat the outer surface of the rotating drum; and The steam generating and supplying step sprays water onto the outer surface of the rotating drum heated in the heating step using the nozzle to generate steam, and the steam flows into the interior of the drum through the through holes of the drum.

2. The control method of the laundry device according to claim 1, wherein: The nozzles are provided to spray water in an inclined direction from an upper portion to a lower portion toward an outer surface of the drum.

3. The control method of the laundry device according to claim 1, wherein: Also includes: After the steam generating and supplying step is completed, the drum and the induction heater are stopped after a preset first time.

4. The control method of the laundry device according to claim 3, wherein: The steaming step is further comprised of determining whether to terminate the steaming step. In the steaming end determination step, if it is determined that the steaming step is to be ended, the steaming step is ended; if it is determined that the steaming step is not to be ended, the steaming step is executed again.

5. The control method of the laundry device according to claim 4, wherein: The steam end judgment step includes: If the steaming step is executed a preset number of times, it is determined that the steaming step is terminated.

6. The control method of the laundry device according to claim 4, characterized in that: The steam end judgment step includes: If the temperature detected by the drying temperature sensor or the washing water temperature sensor is above the preset target temperature, it is determined that the steam step is terminated.

7. The control method of the laundry device according to claim 4, characterized in that: The steam end judgment step includes: The drying degree is calculated by the temperature difference detected by the drying temperature sensor and the washing water temperature sensor, and when the target drying degree is reached, it is determined that the steam step is terminated.

8. The control method of the laundry device according to claim 4, wherein: The steam generating and supplying step further includes the step of setting the amount of water to be supplied through the nozzle, The steam end judgment step includes: If the set water amount is supplied, it is determined that the steam step is ended.

9. The control method of the laundry device according to claim 1, wherein: The steam step is performed in a drying course for drying the object or a care course for deodorizing and reducing wrinkles on the dried object.

10. The control method of the laundry device according to claim 9, wherein: The drying process includes: a drying step of drying the object; a step of determining whether the drying program includes the steam step; If it is determined that the steaming step is included, supplying steam to the object; and An additional drying step of drying the object is performed after the steaming step.

11. The control method of the laundry machine according to claim 9, wherein: The nursing process includes: a preheating step to heat the drum before generating steam; the steaming step of supplying steam to the object; a drying step of drying the object; and A cooling step of cooling the object.

12. The control method of a laundry machine according to claim 1, wherein: In the steam generating and supplying step, the drum is driven to perform filtering motion, The filtering motion is a motion in which the object adheres to the inner circumferential surface of the drum and rotates integrally with the drum as the drum rotates at 70 to 120 RPM.

13. The control method of a laundry machine according to claim 1, wherein: The steaming step is performed to reduce static electricity and wrinkles on the objects at a later stage of a drying process in which the induction heater heats the drum to remove moisture from the wet objects.

14. The control method of the laundry device according to claim 13, wherein: In the steam step, In the heating step, the drum is driven to perform filtering motion and the induction heater is driven, After the heating step, in the steam generating and supplying step, the drum maintains the filtering motion and sprays water.

15. The control method of a laundry machine according to claim 1, wherein: The induction heater is provided on the upper portion of the cylindrical outer circumference of the outer barrel, and the heating surface of the drum is formed on the upper portion of the cylindrical outer circumference of the drum opposite to the induction heater.

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