Patent Description:
Existing dryers or clothing care devices use a venting method for heating air brought in from outside with a heater, or a closed circulation method for heating air in a chamber by continuous circulation of the air using a heat pump cycle, to supply hot air into the chamber.

The venting method, however, has problems of releasing hot and humid air with bad smell to the outside, or causing a large temperature difference in the chamber due to air brought in from outside.

In terms of the closed circulation method, because air is heated while continuously circulating inside the device, continuous heat buildup occurs, and a constant temperature of the air supplied into the chamber may not be maintained. The heat buildup continued in the chamber may cause thermal damage to objects to be dried. For example, <CIT> discloses a control method of a clothes treating apparatus comprising an evaporator, a condenser, an air supplying device having an expansion valve and a fan. The fan to rotates by a first RPM and supplies the air by the supplying device; compares the drive pressure of a compressor to a given reference; adjusts the RPM of the fan to enable the detected drive pressure to be included in a trustable interval, when the detected drive pressure of the compressor is larger than the given reference. <CIT> describes a method for controlling cooling fans for variable electrical loads and a controller monitors cooling fan output, ambient temperature and the electrical load. The controller then matches the fan speed and resulting cooling to the existing electrical load and ambient temperature.

The present invention provides a shoe care apparatus and a method of controlling the same that may increase an operating rate of a compressor even in an environment of a high outside air temperature.

According to the present invention, a shoe care apparatus is provided and includes: a chamber including an air inlet and an air outlet; a first duct connected to the air outlet; an evaporator inside the first duct; a condenser inside the first duct; a second duct connecting the first duct to the air inlet; a holder in the chamber and connected to the air inlet; a first fan configured to circulate air through the first duct, the second duct, the holder, and the chamber; a compressor inside a machine room of the shoe care apparatus, the compressor separated from the chamber and the first duct and configured to discharge a refrigerant to the condenser; a second fan inside the machine room, and configured to allow air in the machine room to flow; a temperature sensor configured to measure an outside air temperature; and a processor, wherein the processor is configured to control an operation of the second fan based on the outside air temperature and an operation state of the compressor and the processor is configured to perform fuzzy control to control the operating frequency of the compressor so that a temperature of the air heated by the condenser (<NUM>) follows a target temperature.

In a further aspect, the present invention provides a method of controlling a shoe care apparatus. The shoe car apparatus includes a first duct connected to an air outlet of a chamber, a second duct connected to an air inlet of the chamber, a holder in the chamber, a first fan configured to move air into the chamber, and a compressor located inside a machine room of the shoe care apparatus that is separated from the first duct. The method includes: determining an outside air temperature using a temperature sensor; and controlling an operation of a second fan located in the machine room, based on the outside air temperature and an operation state of the compressor performing fuzzy control to control the operating frequency of the compressor so that a temperature of the air heated by the condenser follows a target temperature.

According to the present invention, a shoe care apparatus and a method of controlling the same are provided that can increase an operating rate of a compressor even in an environment of a high outside air temperature. As the compressor's operating rate increases, an actual time for dehumidification can increase, an overall operation time of the shoe care apparatus can be reduced, and a usable temperature range of the shoe care apparatus can be extended. Accordingly, a dehumidification performance of the shoe care apparatus can be improved.

Also, the shoe care apparatus and the method of controlling the same can maintain a constant air temperature in a chamber, while circulating air in the enclosed apparatus using a heat pump cycle. Accordingly, thermal damage to objects to be dried due to heat buildup in the chamber can be prevented.

The shoe care apparatus and the method of controlling the same can also reduce a heat up time of the air in the chamber by efficiently utilizing a maximum frequency of the compressor without damaging a control circuit due to excessive current.

The shoe care apparatus and the method of controlling the same can also maintain a comfortable environment around the shoe care apparatus by not releasing contaminated air from drying and deodorizing process to the outside.

Like reference numerals throughout the specification denote like elements. Also, embodiments of the present invention may include additional and/or alternative elements that are not explicitly described in the disclosure, and descriptions of elements well-known in the art to which the disclosure pertains and/or repeated descriptions may be omitted. The terms such as "~part", "~member", "~module", "~block", and the like may refer to at least one process processed by at least one hardware or software. According to embodiments, a plurality of a "~part", "~member", "~module", "~block" may be embodied as a single element, or a single "~part", "~member", "~module", "~block" may include a plurality of elements.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly or indirectly connected to the other element, wherein the indirect connection includes "connection" via a wireless communication network or electrically through electrical wiring.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to limit the disclosure. It is to be understood that the singular forms include plural forms as well, unless the context clearly dictates otherwise.

The terms including ordinal numbers like "first" and "second" may be used to explain various components, but the components are not limited by the terms. The terms are only for the purpose of distinguishing a component from another.

The terms "forward (or front)", "rearward (or behind)", "left", and "right" as used herein are defined with respect to the drawings, but the terms may not restrict the shape and position of the respective components.

Hereinafter, non-limiting example embodiments of the present invention will be described in detail.

<FIG> illustrates an exterior of a shoe care apparatus according to an embodiment. <FIG> illustrates an interior of a shoe care apparatus according to an embodiment. <FIG> is a cross-sectional view of a shoe care apparatus viewed from a front of the shoe care apparatus according to an embodiment.

Referring to <FIG>, <FIG>, and <FIG>, a shoe care apparatus <NUM> may include a main body <NUM> forming an exterior appearance, and a door <NUM> rotatably coupled to the main body <NUM>.

The main body <NUM> may be provided in a rectangular shape with an open front side. An opening 10a may be formed on the open front side of the main body <NUM>. The door <NUM> may be rotatably coupled to the main body <NUM> to open and close the open front side of the main body <NUM>. The door <NUM> may be coupled to the main body <NUM> by a hinge <NUM>.

A direction in which the door <NUM> of the shoe care apparatus <NUM> is installed may be referred to as a front of the shoe care apparatus <NUM>. An outer surface of the door <NUM> may be referred to as the front of the shoe care apparatus <NUM>. Based on the above, rear, left, right, upper and lower sides of the shoe care apparatus <NUM> may be defined.

The main body <NUM> may be formed such that a front length extending in a first direction X is different from a side length extending in a second direction Y. That is, the front surface of the main body <NUM> may be formed in length L1 longer than a length L2 of the side surface of the main body <NUM>. Such a configuration enables the shoe care apparatus <NUM> to be easily installed even in a narrow entrance hall. The length of the front surface of the main body <NUM> may be defined as the first length L1 and the length of the side surface of the main body <NUM> may be defined as the second length L2.

The door <NUM> may include a control panel <NUM> arranged on a front or top surface of the door <NUM>. The control panel <NUM> may receive various commands from a user. In addition, the control panel <NUM> may display various information relating to an operation of the shoe care apparatus <NUM>. For example, the user may use the control panel <NUM> to select a type of shoes to be cared for, and to set a suitable care process for the shoes.

The control panel <NUM> may include a display for displaying information about operations of the shoe care apparatus <NUM>. In addition, the control panel <NUM> may include at least one of a button or a touch screen.

Also, an outer case <NUM> that is a part of the main body <NUM> may be provided with at least one ventilation hole <NUM> for ventilation between air inside a machine room <NUM> and outside air. Because the machine room <NUM> is disposed below a chamber <NUM> within the main body <NUM>, the at least one ventilation hole <NUM> may be arranged in a lower portion of the outer case <NUM> of the main body <NUM> to correspond to a position of the machine room <NUM>. For example, the at least one ventilation hole <NUM> may be arranged in at least one of the sides or the rear of the main body <NUM>.

The door <NUM> may include a hanging member <NUM> (e.g., a hanger). The hanging member <NUM> may be arranged on one side of the door <NUM> facing the interior of the chamber <NUM> and at least one hanging member may be provided. The hanging member <NUM> may be used for hanging a handle <NUM> (refer to <FIG>) of a holder <NUM>. The hanging member <NUM> may facilitate storage of the holder <NUM>. The hanging member <NUM> may be used for other purposes.

The main body <NUM> may include the outer case <NUM> and an inner case <NUM> disposed inside the outer case <NUM>. The inner case <NUM> may form the chamber <NUM>. The holder <NUM> on which shoes may be held may be provided inside the chamber <NUM>. The chamber <NUM> may form a space in which shoes are accommodated. The chamber <NUM> may include a top surface 12a, a bottom surface 12b, a left surface 12c, a right surface 12d, and a rear surface 12e of the inner case <NUM>.

The holder <NUM> and an installation rail <NUM> may be arranged in the chamber <NUM>. The holder <NUM> and the installation rail <NUM> may be installed on the left surface 12c or the right surface 12d of the chamber <NUM>. That is, the holder <NUM> may be installed to show a side of the shoes when viewed from the front of the shoe care apparatus <NUM>. To this end, the side surface of the main body <NUM> may be formed in a length shorter than a length of the front surface of the main body <NUM>. However, positions of the holder <NUM> and the installation rail <NUM> are not limited thereto.

At least one holder <NUM> may be provided. The holder <NUM> may be provided in a shape to be inserted into the shoes. In addition, the holder <NUM> is detachable from the chamber <NUM>. That is, the holder <NUM> may be coupled to the installation rail <NUM> arranged on the side surface of the chamber <NUM> and is detachable from the installation rail <NUM>. For example, the holder <NUM> may be inserted into the installation rail <NUM> along the second direction Y. Because the holder <NUM> is provided detachably, a space in the chamber <NUM> may be efficiently used depending on a size of the shoes.

The chamber <NUM> may include an air inlet <NUM> and an air outlet <NUM>. The air inlet <NUM> may be formed on a sidewall of the inner case <NUM>. For example, the air inlet <NUM> may be formed on the left surface 12c of the chamber <NUM>. A plurality of the air inlet <NUM> mat be provided. Air heated by a condenser <NUM> may be supplied into the chamber <NUM> through the air inlet <NUM>. The air inlet <NUM> may be formed various shapes. For example, a shape of the air inlet <NUM> may be circular, rectangular, or polygonal.

The air outlet <NUM> may be arranged on the bottom surface 12b of the chamber <NUM>. For example, the air outlet <NUM> may be disposed at a front side of the bottom surface 12b. Air in the chamber <NUM> may flow to a first duct <NUM> through the air outlet <NUM>. The air outlet <NUM> may be comprised of a central hole 31a and a grille 31b including a plurality of side holes.

The machine room <NUM> may be arranged under the chamber <NUM>. The machine room <NUM> may be disposed between the outer case <NUM> and the inner case <NUM>. The machine room <NUM> may be distinguished from the chamber <NUM> by the inner case <NUM>. Although not illustrated, a machine room cover may be provided at the rear of the main body <NUM>. The machine room cover may be provided in a lower portion of the outer case <NUM> to correspond to a position of the machine room <NUM>. Further, the machine room cover may include at least one ventilation hole <NUM> for ventilation between air inside the machine room <NUM> and outside air.

In the machine room <NUM>, provided are a compressor <NUM>, an evaporator <NUM>, the condenser <NUM>, an expansion device <NUM> (e.g., an expander) (refer to <FIG>), a deodorizer <NUM>, the first duct <NUM>, a first fan 47a, a second fan 47b, a first temperature sensor <NUM>, and a second temperature sensor <NUM>. In addition, a sterilizer <NUM> may be arranged within the chamber <NUM> or within the machine room <NUM>. In <FIG> and <FIG>, the sterilizer <NUM> is shown as being provided within the chamber <NUM>.

The compressor <NUM>, the evaporator <NUM>, the condenser <NUM>, and the expansion device <NUM> may be defined as a heat pump device <NUM> (e.g., a heat pump) (refer to <FIG>). The heat pump device <NUM> may dehumidify and heat air circulating through the chamber <NUM>. The heat pump device <NUM> may supply heated air into the chamber <NUM>.

The machine room <NUM> may be provided with a third temperature sensor <NUM> (refer to <FIG>) arranged on an inlet side of the evaporator <NUM>, a fourth temperature sensor <NUM> (refer to <FIG>) arranged on an outlet side of the compressor <NUM>, and a current sensor <NUM> (refer to <FIG>) that measures a compressor current applied to the compressor <NUM>.

The first duct <NUM> is a duct positioned under the chamber <NUM> and may be connected to the chamber <NUM>. That is, the first duct <NUM> may be connected to the bottom surface 12b of the chamber <NUM>. The first duct <NUM> may be referred to as a lower duct. The first duct <NUM> may be connected to the air outlet <NUM> to form a first flow path 46a that guides the air having passed the air outlet <NUM> to the first fan 47a. Also, the first duct <NUM> may be connected to a second duct <NUM> arranged within a side of the main body <NUM>. A space inside the first duct <NUM> may be separated from the machine room <NUM>.

The second duct <NUM> may be referred to as a upper duct. The second duct <NUM> may be provided outside of a sidewall of the inner case <NUM> in the second direction Y or the first direction X of the shoe care apparatus <NUM>. One end of the second duct <NUM> may be connected to at least one air inlet <NUM> (also referred to as a "supply port"), and the other end may be connected to the first duct <NUM>. The second duct <NUM> may form a second flow path <NUM> that guides air to the air inlet <NUM>.

The evaporator <NUM> and the condenser <NUM> may be disposed in the first duct <NUM>. The evaporator <NUM>, the condenser <NUM> and the first fan 47a may be arranged in the first direction X. The first fan 47a may be installed inside the first duct <NUM> or between the first duct <NUM> and the second duct <NUM>. The evaporator <NUM> may be located further upstream of the air flow than the condenser <NUM>. The compressor <NUM> may be located outside of the first duct <NUM>. The compressor <NUM>, the evaporator <NUM>, and the condenser <NUM> may be connected by refrigerant pipes.

An interior space of the chamber <NUM> and the first duct <NUM> may be separated from the machine room <NUM> in which the compressor <NUM> is located. That is, the first flow path 46a may be separated from the machine room <NUM>. Air flowing through the chamber <NUM> and the first flow path 46a of the first duct <NUM> may not flow out to the machine room <NUM>, and air inside the machine room <NUM> may not flow into the first duct <NUM> and the chamber <NUM>.

The first fan 47a may be provided between the heat pump device <NUM> and the chamber <NUM> to circulate air. The first fan 47a may rotate based on a predetermined revolutions per minute (RPM). Specifically, the first fan 47a may intake air brought into the first duct <NUM> and discharge the air to the second duct <NUM>. The air brought into the first duct <NUM> through the air outlet <NUM> may be dried while passing the evaporator <NUM> of the heat pump device <NUM>, heated while passing the condenser <NUM>, and then discharged back to the chamber <NUM> through the second duct <NUM> and the air inlet <NUM>.

The second fan 47b may be located outside the first duct <NUM>. For example, the second fan 47b may be disposed adjacent to the compressor <NUM>. The second fan 47b may move air in the machine room <NUM>. The second fan 47b may blow towards the compressor <NUM> and/or the first duct <NUM>. The second fan 47b may also be disposed adjacent to the at least one ventilation hole <NUM>. The second fan 47b may move air in the machine room <NUM> to the outside through the at least one ventilation hole <NUM>, and may draw outside air into the machine room <NUM>. Wind generated by the operation of the second fan 47b may cool the compressor <NUM> and the first duct <NUM>, and may reduce a temperature in the machine room <NUM>.

A rotation speed of the second fan 47b may be controlled within a predetermined range of a minimum rotation speed and a maximum rotation speed. For example, the rotation speed of the second fan 47b may be set within a range of <NUM> RPM and <NUM> RPM. The minimum and maximum rotation speeds of the second fan 47b may vary according to embodiments.

The heat of hot outside air and the heat generated by the compressor <NUM> may be conducted or radiated through the first duct <NUM> to the air flowing through the first flow path 46a. When heat from the outside is transferred into the chamber <NUM> through the first duct <NUM>, heat buildup inside the chamber <NUM> may increase, preventing the temperature in the chamber <NUM> from maintaining at a target temperature. By locating the second fan 47b within the machine room <NUM>, overheating in the chamber <NUM> may be suppressed.

The first fan 47a and the second fan 47b may each include a motor and a blade. The blade may be rotated by motion of the motor. The rotation of the blade may cause air to flow. The first fan 47a and the second fan 47b may be of various types. For example, the first fan 47a and the second fan 47b may each be provided as a centrifugal fan.

Also, the deodorizer <NUM> may be disposed in the first duct <NUM>. The deodorizer <NUM> may include a deodorizing filter 45a and ultraviolet light emitting diode (UV LED) 45b. The deodorizing filter 45a and the UV LED 45b may be disposed adjacent to the air outlet <NUM> of the chamber <NUM>. The UV LED 45b may irradiate light to the deodorizing filter 45a to remove odors from the air. For example, the deodorizing filter 45a may include at least one from among a ceramic filter, a photocatalytic filter, and an activated carbon filter.

The sterilizer <NUM> may be further disposed in the chamber <NUM> or in the first duct <NUM>. The sterilizer <NUM> may remove germs contained in the air. The sterilizer <NUM> may include at least one from among an ultraviolet lamp, an ultraviolet LED, a xenon lamp, an ozone generator, and a sterilizing spray.

A drain tub <NUM> may be disposed in a lower portion of the main body <NUM>, i.e., underneath the machine room <NUM>. The drain tub <NUM> may store condensate water produced by the evaporator <NUM>. The drain tub <NUM> is detachable from the main body <NUM>.

At least one shelf <NUM> may be arranged in the chamber <NUM>. Shoes may be placed on the at least one shelf <NUM>. In addition, the at least one shelf <NUM> may include a duct shelf <NUM>. The duct shelf <NUM> may form a flow path 103b therein and may include a hole 103a at a lower surface thereof. Air rising from the first fan 47a through the second duct <NUM> may be discharged into the chamber <NUM> through the hole 103a of the duct shelf <NUM>. In addition, the duct shelf <NUM> may be formed with a hole <NUM> at a top surface thereof.

A side surface of the duct shelf <NUM> may be connected to a circular duct <NUM> disposed in the second duct <NUM>. Air may be discharged into the chamber <NUM> through a nozzle 104a of the circular duct <NUM>. Air may be supplied to the duct shelf <NUM> after passing the circular duct <NUM>. The circular duct <NUM> may have various shapes. For example, the circular duct <NUM> may have a fan shape.

The first temperature sensor <NUM> may measure a first temperature of air heated by the condenser <NUM>. The first temperature sensor <NUM> may also be referred to as an "introduced air temperature sensor. " Hereinafter, a temperature of the air measured by the first temperature sensor <NUM> is defined as the first temperature. The first temperature sensor <NUM> may be arranged in a flow path between the condenser <NUM> and the first fan 47a. A processor <NUM> (refer to <FIG>) of the shoe care apparatus <NUM> may control an operation frequency of the compressor <NUM> based on the first temperature measured by the first temperature sensor <NUM>.

The second temperature sensor <NUM> may measure a temperature of air at the air outlet <NUM> of the chamber <NUM>. The second temperature sensor <NUM> may also be referred to as an "discharged air temperature sensor. " The second temperature sensor <NUM> may be disposed in a flow path between the air outlet <NUM> and the deodorizing filter 45a, or between the deodorizing filter 45a and the evaporator <NUM>. A temperature of the air measured by the second temperature sensor <NUM> is hereinafter defined as the second temperature. The processor <NUM> of the shoe care apparatus <NUM> may determine an outside air temperature based on the second temperature measured by the second temperature sensor <NUM> at a start of operation of the shoe care apparatus <NUM>.

<FIG> is a perspective view of a holder installed in a chamber viewed from above. <FIG> is a perspective view of a holder installed in a chamber viewed from below.

Referring to <FIG> and <FIG>, the holder <NUM> may include support frames (e.g., a first support frame <NUM> and a second support frame <NUM>), a handle <NUM>, a support body <NUM>, and a coupler <NUM>. The support body <NUM> may connect the handle <NUM>, the coupler <NUM>, the first support frame <NUM>, and the second support frame <NUM>.

The support frames may include the first support frame <NUM> and the second support frame <NUM>. The first support frame <NUM> and the second support frame <NUM> protrude from a side surface of the chamber <NUM> in the first direction X and may be spaced apart from each other in the second direction Y. Although two support frames are shown, one or more than two support frames may be provided. Because the first support frame <NUM> and the second support frame <NUM> are spaced apart from each other in the second direction Y, a plurality of shoes may be held thereon.

Meanwhile, the first support frame <NUM> and the second support frame <NUM> may be inclined at a predetermined angle to prevent the shoes caught from falling out. That is, the first support frame <NUM> and the second support frame <NUM> may be inclined upwardly with respect to the bottom surface 12b of the chamber <NUM>. Accordingly, the shoes held by the holder <NUM> may be prevented from falling out.

The handle <NUM> may facilitate moving or detaching the holder <NUM>. A user may move the holder <NUM> by gripping the handle <NUM>. In addition, the user may easily mount the holder <NUM> on the installation rail <NUM> using the handle <NUM>. The handle <NUM> may be of various shapes. For example, the handle <NUM> may be provided in a triangular shape. In addition, a grip member 55a (e.g., a grip) may be formed on the handle <NUM>. The user may easily grip the handle <NUM> using the grip member 55a.

The coupler <NUM> may be connected to the air inlet <NUM> and guide the air supplied through the second duct <NUM> to the first support frame <NUM> and the second support frame <NUM>. The coupler <NUM> is shown as having a hollow oval shape, but is not limited thereto and may be provided in various shapes.

Referring to <FIG>, the first support frame <NUM> and the second support frame <NUM> of the holder <NUM> may include a first nozzle 51a and a second nozzle 52a, respectively. The first support frame <NUM> may include the first nozzle 51a and the second support frame <NUM> may include the second nozzle 52a. The first nozzle 51a and the second nozzle 52a may be formed on at least one of bottom surfaces 51b and 52b or side surfaces 51c and 52c of the support frames. The first nozzle 51a and the second nozzle 52a may be provided in various shapes. For example, the first nozzle 51a and the second nozzle 52a may be circular, elliptical or rectangular. Heated air may be supplied to the chamber <NUM> through the first nozzle 51a and the second nozzle 52a.

The holder <NUM> may further include a fastening groove <NUM>. A fixing projection <NUM> (refer to <FIG>) of the installation rail <NUM> may be inserted into the fastening groove <NUM> to fix the holder <NUM>. The holder <NUM> may further include a reinforcing member <NUM>. The reinforcing member <NUM> is connected to the handle <NUM> to reinforce the support body <NUM>.

<FIG> illustrates an installation rail installed in a chamber.

Referring to <FIG>, one end <NUM> of the installation rail <NUM> is closed to prevent the holder <NUM> from falling out, and the other end <NUM> of the installation rail <NUM> has an open form so that the holder <NUM> may be inserted therein. The installation rail <NUM> may include a fixing frame <NUM> and the fixing projection <NUM>.

The fixing frame <NUM> extends from the one end <NUM> of the installation rail <NUM> to the other end <NUM> and may receive the coupler <NUM> of the holder <NUM>. The fixing projection <NUM> may be inserted into the fastening groove <NUM> of the holder <NUM>. The holder <NUM> may thus be fixed to the installation rail <NUM>. The holder <NUM> is detachable from the installation rail <NUM>.

Also, the installation rail <NUM> may include an air hole <NUM>. Air brought in through the second duct <NUM> and the air inlet <NUM> of the chamber <NUM> may be supplied to the holder <NUM> through the air hole <NUM> in the installation rail <NUM>. That is, air brought in from the air inlet <NUM> may be supplied to the first support frame <NUM> and the second support frame <NUM> of the holder <NUM> through the air hole <NUM>, and may be sprayed into the chamber <NUM> through the first nozzle 51a and the second nozzle 52a.

<FIG> is a schematic diagram illustrating a flow of air and refrigerant in a shoe care apparatus according to an embodiment.

Referring to <FIG>, the shoe care apparatus <NUM> according to an embodiment may include the chamber <NUM> for receiving an object S (e.g., shoes) to be dried, the heat pump device <NUM> dehumidifying and heating air in the chamber <NUM> to dry the object S, the first temperature sensor <NUM> measuring a first temperature of air heated by the condenser <NUM>, the second temperature sensor <NUM> measuring a second temperature of the air having passed through the air outlet <NUM> of the chamber <NUM>, the first fan 47a provided between the chamber <NUM> and the heat pump device <NUM> for circulating air, and the second fan 47b provided outside the first duct <NUM> for circulating air in the machine room <NUM>.

The heat pump device <NUM> includes the compressor <NUM>, the condenser <NUM>, the expansion device <NUM>, and the evaporator <NUM>. The compressor <NUM>, the condenser <NUM>, the expansion device <NUM>, and the evaporator <NUM> may be connected to each other by refrigerant pipes to form a heat pump cycle, and a refrigerant may be circulated in accordance with the heat pump cycle while flowing in the refrigerant pipes. The evaporator <NUM> and condenser <NUM> may be located inside the first duct <NUM>, and the compressor <NUM> and expansion device <NUM> may be located outside the first duct <NUM>.

The compressor <NUM> compresses a low-temperature and low-pressure vapor-phase refrigerant and discharges a high-temperature and high-pressure vapor-phase refrigerant. The discharged vapor-phase refrigerant may flow into the condenser <NUM>, and the high-temperature and high-pressure vapor-phase refrigerant may be condensed into a high-pressure liquid-state or approximately liquid-state refrigerant equal to or lower than a condensation temperature. The high-pressure liquid-state or approximately liquid-state refrigerant that has passed the condenser <NUM> is expanded and decompressed by the expansion device <NUM>, and the low-temperature and low-pressure two-phase refrigerant that has passed the expansion device <NUM> flows into the evaporator <NUM>. The two-phase refrigerant may be evaporated to vapor-phase refrigerant in the evaporator <NUM>.

The chamber <NUM> and the heat pump device <NUM> may be connected by the first duct <NUM> and the second duct <NUM>, and the air in the chamber <NUM> moves through the duct and may be circulated between the heat pump device <NUM> and the chamber <NUM>.

Hot and humid air in the chamber <NUM> may exchange heat with the refrigerant while passing the evaporator <NUM>. Specifically, the low-temperature and low-pressure two-phase refrigerant brought into the evaporator <NUM> may be evaporated into a vapor-phase refrigerant by absorbing heat from the hot and humid air passing the evaporator <NUM>. The hot and humid air passing the evaporator <NUM> is cooled and dehumidified at the same time into cool and dry air.

After passing the evaporator <NUM>, the cool and dry air flows into the condenser <NUM>, and heat exchange may occur between the high-temperature and high-pressure vapor-phase refrigerant and the cool and dry air in the condenser <NUM>. The high-temperature and high-pressure vapor-phase refrigerant may release heat while being condensed into a liquid-phase or approximately liquid-phase refrigerant and, and the cool and dry air may be heated by absorbing the heat released during the condensation of the refrigerant.

The hot and dry air having passed the condenser <NUM> may flow back into the chamber <NUM>. The object S (e.g., shoes) accommodated in the chamber <NUM> may be dried by such an air circulation cycle.

The expansion device <NUM> may be implemented with at least one of a capillary tube or an electrical expansion valve that may control opening degrees based on an electrical signal.

The compressor <NUM> may be implemented as a frequency changeable inverter compressor. The frequency of the compressor <NUM> refers to revolutions per second of a motor connected to a compression room of the compressor <NUM>. The compressor <NUM> may operate at a predetermined starting frequency at the start of a dry course, and afterward, to increase the temperature, the compressor <NUM> may operate at an operation frequency. Meanwhile, the compressor <NUM> may operate within a range from a minimum frequency and a maximum frequency. A minimum operation frequency and a maximum operation frequency may be set in advance depending on the embodiment.

The shoe care apparatus <NUM> may further include the third temperature sensor <NUM> provided at an inlet side of the evaporator <NUM>, and the fourth temperature sensor <NUM> provided at an outlet side of the compressor <NUM>. The third temperature sensor <NUM> may be referred to as an "evaporator inlet temperature sensor" and the fourth temperature sensor <NUM> may be referred to as a "compressor outlet temperature sensor. " The third temperature sensor <NUM> and the fourth temperature sensor <NUM> may be installed outside or inside of the refrigerant pipe, respectively, to measure a temperature of the refrigerant circulating in the heat pump cycle. The third temperature sensor <NUM> may measure a temperature of the refrigerant flowing into the evaporator <NUM>, and the fourth temperature sensor <NUM> may measure a temperature of the refrigerant discharged from the compressor <NUM>.

The shoe care apparatus <NUM> may further include the current sensor <NUM> that measures a compressor current applied to the compressor <NUM>. The current sensor <NUM> may measure a power consumed by the compressor <NUM>.

<FIG> is a control block diagram of a shoe care apparatus according to an embodiment.

Referring to <FIG>, the shoe care apparatus <NUM> may include the control panel <NUM>, the heat pump device <NUM>, the deodorizer <NUM>, the first fan 47a, the second fan 47b, the sterilizer <NUM>, the first temperature sensor <NUM>, the second temperature sensor <NUM>, the third temperature sensor <NUM>, the fourth temperature sensor <NUM>, the current sensor <NUM>, a power module <NUM>, a memory <NUM> and the processor <NUM>. Although not illustrated, the shoe care apparatus <NUM> may further include a communication device for transmitting and receiving data with an external device. The processor <NUM> may be electrically connected to the aforementioned constituent components of the shoe care apparatus <NUM> and control operations of the constituent components.

The power module <NUM> may supply power to the constituent components of the shoe care apparatus <NUM>. The power module <NUM> may be implemented with a printed circuit board and a power circuit mounted on the printed circuit board. For example, the power module <NUM> may include a capacitor, a coil, a resistor, a processor, and the like, which are mounted on the power circuit board.

The shoe care apparatus <NUM> may include the memory <NUM> storing programs, instructions and data for controlling operations of the shoe care apparatus <NUM>. The shoe care apparatus <NUM> may also include the processor <NUM> generating a control signal for controlling operations of the shoe care apparatus <NUM> based on the programs, instructions and/or data recorded and/or stored in the memory <NUM>. The processor <NUM> and the memory <NUM> may be implemented as a single control circuit or as a plurality of circuits.

The processor <NUM> may include a logic circuit and an operational circuit in hardware. The processor <NUM> may process data according to the program and/or instruction provided from the memory <NUM>, and generate a control signal according to a result of the processing. For example, when a user inputs a command through the control panel <NUM>, the processor <NUM> may process the input command and controls each component of the shoe care apparatus <NUM> to perform an operation corresponding to the input command.

The memory <NUM> may include a volatile memory, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM), for temporary storage of data, and a non-volatile memory, such as Read Only Memory (ROM), Erasable Programmable Read Only Memory (EPROM), or Electrically Erasable Programmable Read Only Memory (EEPROM), for long-term storage of data.

As described in <FIG>, the control panel <NUM> may be arranged on the door <NUM>. Although the control panel <NUM> is illustrated as being arranged on a front surface of the door <NUM>, a position of the control panel <NUM> is not limited thereto and may be provided in various positions. The processor <NUM> may determine a target temperature based on a selection signal of a shoe type and care course transmitted from the control panel <NUM>. Also, the processor <NUM> may determine an operation time of the shoe care apparatus <NUM> based on the selected shoe type and care course.

A user may use the control panel <NUM> to select a shoe type to be cared for. For example, the control panel <NUM> may provide at least one of a shoe type menu to allow the user to select a shoe type, or a care course menu to allow the user to select a care course. Shoe types may include types according to use or shape, such as heels, sneakers, hiking shoes, boots, sandals, rain boots, and the like. The shoe types may also include types according to material, such as leather, cotton, nylon, synthetic materials, silk, enamel, suede, neoprene, and the like.

The processor <NUM> may determine a target temperature of air to be supplied into the chamber <NUM> based on a shoe type. Because different types of shoes have different characteristics, the target temperature for caring the shoes may be set differently according to the characteristics of the shoes. For example, for shoes of synthetic materials, a low target temperature of <NUM> or higher and less than <NUM> may be set. For shoes of a leather material, a medium target temperature of <NUM> or higher and less than <NUM> may be set. For shoes of a cotton material, a high target temperature of <NUM> or higher and less than <NUM> may be set.

As another example, when two or more types of shoes are to be cared for or the shoes contain moisture, a target temperature for dehumidification may be set to less than <NUM>, and a target temperature for deodorization may be set to <NUM> or higher and less than <NUM>. By setting the target temperature as described above, damage to the shoes may be prevented. Furthermore, when both dehumidification and deodorization are required, deodorization may be performed after dehumidification. Specifically, the moisture contained in the shoes is removed at a low temperature and deodorization is then performed at a high temperature, thereby minimizing the damage to the shoes.

In addition, the user may use the control panel <NUM> to set a suitable care course. The processor <NUM> may determine an operation time of the shoe care apparatus <NUM> based on the selected care course. For example, the care course may include at least one from among a standard course, a quick course, an intense course, and a clean storage course. The standard course is a default care course, and may be defined as a care course in which the shoe care apparatus <NUM> is operated for a standard time (e.g., <NUM> minutes) for which dehumidification and deodorization effects are normally exerted. The quick course may be defined as a care course that may exert minimum dehumidification and deodorization effects within a shorter time than in the standard course. The intense course may be defined as a care course that may exert maximum dehumidification and deodorization effects by being operated for a longer time than in the standard course. Furthermore, the clean storage course may be defined as a care course for keeping the shoes for a long time. As such, various care courses may be suitably applied to various shoes, thereby increasing convenience of shoe caring and user satisfaction.

The processor <NUM> may determine an outside air temperature based on a temperature measured by the second temperature sensor <NUM> at the start of operation of the shoe care apparatus <NUM>. Before the start of operation of the shoe care apparatus <NUM>, the door <NUM> may be opened to put shoes into the chamber <NUM>. In this case, the temperature of the air in the chamber <NUM> is equivalent to the outside air temperature. Also, at the start of operation of the shoe care apparatus <NUM>, the air in the chamber <NUM> is in a non-heated state. Accordingly, at the start of operation of the shoe care apparatus <NUM>, the outside air temperature may be determined by using the second temperature sensor <NUM> located at the air outlet <NUM> of the chamber <NUM>.

The processor <NUM> may determine an operation frequency of the compressor <NUM> based on the target temperature and the outside air temperature, and operate the compressor <NUM> at the determined operation frequency. The target temperature and the outside air temperature are factors that have large influences on determination of an operation frequency of the compressor <NUM>. For example, based on the outside air temperature being a low temperature, the processor <NUM> may set the operation frequency of the compressor <NUM> to a high value to force the temperature of the air supplied into the chamber <NUM> to quickly reach the target temperature. The larger the difference between the outside air temperature and the target temperature, the higher value the operation frequency of the compressor <NUM> may be set to. On the contrary, based on the difference between the target temperature and the outside air temperature being small (e.g., when the difference between the target temperature and the outside air temperature is <NUM> or less), the operation frequency of the compressor <NUM> may be set to a low value, because when the temperature in the chamber <NUM> rises suddenly, it may exceed the target temperature.

Also, the processor <NUM> may control the operation frequency of the compressor <NUM> based on a temperature of the air heated by the condenser <NUM> and the target temperature. Specifically, the processor <NUM> may control the operation frequency of the compressor <NUM> based on the first temperature measured by the first temperature sensor <NUM>. When the compressor <NUM> is operated at a fixed operation frequency for the whole operation time, the temperature of the air circulating in the shoe care apparatus <NUM> may constantly rise, failing to maintain the constant target temperature. To prevent the above, the operation frequency of the compressor <NUM> may be controlled.

To maintain the air supplied into the chamber <NUM> at the target temperature, the processor <NUM> of the shoe care apparatus <NUM> performs fuzzy control. The fuzzy control refers to a control method of periodically controlling the operation frequency of the compressor <NUM> for the first temperature of the air heated by the condenser <NUM> to follow the target temperature. The processor <NUM> may increase or decrease the operation frequency of the compressor <NUM> for the first temperature to follow the target temperature, in response to the first temperature reaching a predetermined first threshold temperature. The processor <NUM> may use a fuzzy table stored in advance to determine a control value of the operation frequency. The fuzzy control will be described in detail with reference to <FIG>.

However, in response to the outside air temperature being high (e.g., the outside air temperature equal to or higher than <NUM>) or in response to the target temperature being high (e.g., the target temperature equal to or higher than <NUM>), the target temperature may not be maintained only by fuzzy control that controls a frequency of the compressor <NUM>. For example, when heat from the hot outside air and heat generated by the compressor <NUM> is transferred into the chamber <NUM> through the first duct <NUM>, heat buildup inside the chamber <NUM> increases, preventing the temperature in the chamber <NUM> from maintaining at the target temperature. To complement the limit of the fuzzy control, the processor <NUM> may further perform compressor switching control. The compressor switching control refers to a control method for switching the compressor <NUM> on or off. The compressor switching control will be described in detail with reference to <FIG> and <FIG>.

Meanwhile, when periods in which the operation of the compressor <NUM> is stopped increases or becomes longer, an operating rate of the compressor <NUM> may decrease, causing performance reduction and target temperature following capability. In order to increase the operating rate of the compressor, the processor <NUM> may control an operation of the second fan 47b located in the machine room <NUM>. By operating the second fan 47b in an environment where an outside air temperature is high, overheating of the air supplied into the chamber <NUM> may be suppressed and an operation period of the compressor <NUM> may be increased. In response to the operation period of the compressor <NUM> being increased, the operating rate of the compressor <NUM> increases. A control method of the second fan 47b will be described in detail with reference to <FIG>.

Furthermore, to prevent damage caused by excessive current applied to the compressor <NUM>, the processor <NUM> may perform compressor current control. The compressor current control refers to a control method for controlling a current applied to the compressor <NUM> by periodically controlling the operation frequency of the compressor <NUM> based on a current value or power value applied to the compressor <NUM>. That is, the processor <NUM> may control the operation frequency of the compressor <NUM> so that the compressor current is equal to or less than a predetermined limit current. The processor <NUM> may use a pre-stored current control table to determine a control value of the operation frequency. The compressor current control will be described in detail with reference to <FIG>.

<FIG> is a flowchart schematically illustrating overall operations of a shoe care apparatus according to an embodiment.

Referring to <FIG>, the overall operations of the shoe care apparatus <NUM> may include performing a stabilization course <NUM>, a dry course <NUM> and a cooling course <NUM>. Through the stabilization course <NUM>, the dry course <NUM> and the cooling course <NUM>, shoes placed in the chamber <NUM> may be dried and deodorized.

The processor <NUM> may start an operation of the shoe care apparatus <NUM> based on a user input obtained by the control panel <NUM> (<NUM>). At the start of the operation of the shoe care apparatus <NUM>, the processor <NUM> may determine a target temperature of air to be supplied into the chamber <NUM> based on the user input. With the determining of the target temperature, an operation time of the shoe care apparatus <NUM> may be determined as well. As described above, the target temperature may be determined based on a selection of a shoe type input through the control panel <NUM>, and the operation time may be determined based on a selection of a care course. An operation frequency of the compressor <NUM> may also be determined.

The processor <NUM> may perform the stabilization course <NUM>. In the stabilization course, the processor <NUM> may operate the first fan 47a for a predetermined stabilization time. The processor <NUM> may operate at least one from among the deodorizer <NUM> and the sterilizer <NUM> as well as the first fan 47a. In the stabilization course, the compressor <NUM> may not be operated. Sudden application of a heavy load to the power module <NUM> and the processor <NUM> may be prevented through the stabilization course. Furthermore, whether the fan <NUM> has a failure may be detected by the processor <NUM> in the stabilization course.

Also, the processor <NUM> may determine whether to operate the second fan 47b based on whether an outside air temperature is equal to or higher than a predetermined first operation temperature. For example, based on the outside air temperature being less than the first operation temperature, the processor <NUM> may stop the operation of the second fan 47b. In contrast, based on the outside air temperature being equal to or higher than the first operation temperature, the processor <NUM> may determine a start of the operation of the second fan 47b. In addition, based on whether the outside air temperature is equal to or higher than a predetermined second operation temperature, the processor <NUM> may determine a rotation speed of the second fan 47b. The second operation temperature may be set in advance to be higher than the first operation temperature. For example, the first operation temperature may be set to <NUM>, and the second operation temperature may be set to <NUM>. The processor <NUM> may operate the second fan 47b at a first rotation speed (e.g., a base rotation speed of <NUM> RPM), based on the outside air temperature being higher than the first operation temperature and lower than the second operation temperature, and may operate the second fan 47b at a second rotation speed (e.g., a maximum rotation speed of <NUM> RPM) that is faster than the first rotation speed, based on the outside air temperature being equal to or higher than the second operation temperature.

Meanwhile, even when the outside air temperature is lower than the first operation temperature, the processor <NUM> may operate the second fan 47b at a predetermined rotation speed (e.g., a minimum rotation speed of <NUM> RPM) in order to detect a failure in the second fan 47b and reduce a temperature in the machine room <NUM> including the compressor <NUM> even slightly before starting the dry course.

Subsequently, the processor <NUM> may perform the dry course <NUM>. In the dry course, the processor <NUM> may operate the compressor <NUM> at an operation frequency F1 for a predetermined drying time and operate the first fan 47a in connection with the operation of the compressor <NUM>. The temperature of the air in the chamber <NUM> may be increased by operating the compressor <NUM> at the operation frequency F1. In response to the temperature of the air reaching the target temperature, the processor <NUM> may control the operation frequency F1 of the compressor <NUM>. The target temperature may be maintained by controlling the operation frequency F1 of the compressor <NUM>.

In addition, in the dry course <NUM>, the processor <NUM> may control the operation of the second fan 47b based on an operation state of the compressor <NUM>. For example, the processor <NUM> may increase a rotation speed of the second fan 47b in response to an operation stoppage of the compressor <NUM>, and decrease the rotation speed of the second fan 47b in response to a resumption of the operation of the compressor <NUM>.

In response to the operation of the compressor <NUM> being stopped according to the compressor switching control, the compressor <NUM> and the first duct <NUM> may be cooled even faster by increasing the rotation speed of the second fan 47b. When the compressor <NUM> and the first duct <NUM> are cooled faster, a temperature of the air supplied into the chamber <NUM> may also decrease faster. As the time for the temperature of the air supplied into the chamber <NUM> to fall below the target temperature decreases, a downtime of the compressor <NUM> may also decrease. As the downtime of the compressor <NUM> decreases, the operation time of the compressor <NUM> may increase. Accordingly, the operating rate of the compressor <NUM> may increase.

Next, the processor <NUM> may perform the cooling course <NUM>. In the cooling course <NUM>, the processor <NUM> may operate the first fan 47a for a predetermined cooling time. The processor <NUM> may operate at least one from among deodorizer <NUM> and the sterilizer <NUM> as well as the first fan 47a. Furthermore, the processor <NUM> may simultaneously operate the second fan 47b together during the cooling time.

In the cooling course, the compressor <NUM> is not operated. Through the cooling course, a temperature in the chamber <NUM> may be forced to decrease and the dried shoes may be cooled. Accordingly, after completion of the operation of the shoe care apparatus <NUM>, the user may safely take out the shoes.

<FIG> is a flowchart schematically illustrating operations of a compressor in a dry course.

Referring to <FIG>, the processor <NUM> may first operate the compressor <NUM> for a certain time at a starting frequency F0 (<NUM>). The processor <NUM> may determine an operation frequency F1 of the compressor <NUM> based on the target temperature T* and the outside air temperature To, and operate the compressor <NUM> at the determined operation frequency F1 (<NUM>). The target temperature T* may be determined based on user input, and the outside air temperature To may be determined based on a second temperature measured by the second temperature sensor <NUM> at a start of operation of the shoe care apparatus <NUM>.

Meanwhile, the process of operating the compressor <NUM> at the starting frequency F0 may be omitted. That is, the compressor <NUM> may be operated based on the operation frequency F1 from a beginning of the dry course.

Subsequently, the processor <NUM> may control the operation frequency of the compressor <NUM> based on a temperature T_in of the air heated by the condenser <NUM> and the target temperature T* (<NUM>).

<FIG> is a flowchart illustrating fuzzy control in a method of controlling a shoe care apparatus according to an embodiment. <FIG> illustrates a fuzzy table. <FIG> is a graph illustrating a result of fuzzy control.

Referring to <FIG>, operation <NUM> is the same as described above. The processor <NUM> may operate the compressor <NUM> at the operation frequency F1 determined based on the target temperature T* and the outside air temperature To (<NUM>).

The processor <NUM> may check the temperature T_in of the air heated by the condenser <NUM>. Specifically, the processor <NUM> may check whether the temperature T_in reaches a predetermined first threshold temperature T* - λ (<NUM>). Referring to a graph <NUM> of <FIG>, the operation frequency F1 may be set to a maximum frequency F1_max of the compressor <NUM>. The temperature of the air heated by the condenser <NUM> is measured by the first temperature sensor <NUM> and is defined as the temperature T_in (also referred to as "first temperature").

When the temperature T_in reaches the first threshold temperature T* - λ, fuzzy control may be started. As shown in the graph <NUM> of <FIG>, the fuzzy control may be started at a point in time tf at which the temperature T_in reaches the first threshold temperature T* - λ. That is, when the temperature T_in reaches the predetermined first threshold temperature T* - λ, the processor <NUM> may increase or decrease the operation frequency F1 of the compressor <NUM> for the temperature T_in to follow the target temperature T*. The processor <NUM> may use a fuzzy table <NUM>, that is pre-stored, to determine a control value Δfa of the operation frequency F1, and control the operation frequency F1 of the compressor <NUM> based on the control value Δfa.

Specifically, the processor <NUM> may calculate a temperature difference Td(N) between the target temperature T* and the temperature T_in and a value of variation ΔTd in temperature difference at predetermined intervals (<NUM>). The value of variation ΔTd in temperature difference may be calculated by subtracting a previous temperature difference Td(N-<NUM>) from the current temperature difference Td(N). The processor <NUM> may determine the control value Δfa corresponding to the value of variation ΔTd in temperature difference and the temperature difference Td(N) by referring to the fuzzy table <NUM> (<NUM>). For example, in <FIG>, when the current temperature difference Td(N) is E1 and the value of variation ΔTd in temperature difference is calculated to be - dE2, the control value Δfa of the operation frequency F1 may be determined to be -df1. The control value Δfa as mentioned in the fuzzy control may be referred to as a 'first control value'.

The processor <NUM> may control the operation frequency F1 based on the control value Δfa (<NUM>). That is, controlling of the operation frequency F1 may be performed by adding the control value Δfa to the previous operation frequency F1(N-<NUM>). For example, when the previous operation frequency F1(N-<NUM>) is <NUM>, the operation frequency F1 may be reduced to <NUM> - df1.

Meanwhile, the processor <NUM> may determine an elapsed time from the start of operation of the shoe care apparatus <NUM> and stop operating the shoe care apparatus <NUM> when the operation time is expired (<NUM>, <NUM>).

In <FIG>, it is seen that the temperature T_in of the air flowing into the chamber <NUM> is maintained at the target temperature T* from a point in time ta1 when reaching the target temperature T*. As such, the shoe care apparatus <NUM> in an embodiment may maintain the constant temperature T_in of the air supplied into the chamber <NUM> to follow the target temperature T* by suitably controlling the frequency of the compressor <NUM>.

<FIG> is a graph <NUM> illustrating limits of fuzzy control.

Referring to <FIG>, the compressor <NUM> may operate within a range between a minimum frequency F1_min and a maximum frequency F1_max. However, the temperature T_in in the chamber <NUM> may keep rising and exceed the target temperature T*, even though the operation frequency F1 of the compressor <NUM> decreases after the temperature T_in reaches the target temperature T*. As shown in <FIG>, even though the operation frequency F1 has been reduced to the minimum frequency F1_min at a point in time tm, it is seen that the temperature T_in in the chamber <NUM> continues to rise.

The above problem may occur when an outside air temperature is high (e.g. the outside air temperature equal to or higher than <NUM>) or the target temperature is high (e.g., the target temperature equal to or higher than <NUM>). For example, when heat from the hot outside air and heat generated by the compressor <NUM> is transferred into the chamber <NUM> through the first duct <NUM>, heat buildup inside the chamber <NUM> may increase. In response to the increase in heat buildup in the chamber <NUM>, the temperature in the chamber <NUM> may not be maintained at the target temperature. In this case, the temperature in the chamber <NUM> may not be maintained at the target temperature only by controlling the frequency of the compressor <NUM>. Thus, to complement the limit of the fuzzy control, compressor switching control may be performed.

<FIG> is a flowchart illustrating compressor switching control in a method of controlling a shoe care apparatus according to an embodiment. <FIG> is a flowchart illustrating another embodiment of compressor switching control in a method of controlling a shoe care apparatus according to an embodiment. <FIG> is a graph <NUM> illustrating a result of compressor switching control.

In <FIG> and <FIG>, operation <NUM> is the same as described above. That is, to maintain a temperature of air supplied into the chamber <NUM> at the target temperature, the processor <NUM> may control the operation frequency F1 of the compressor <NUM> based on the control value Δfa (<NUM>).

Referring to <FIG>, the processor <NUM> may check whether the first temperature T_in measured by the first temperature sensor <NUM> reaches a predetermined second threshold temperature T* + δ (<NUM>). The first temperature reaching the second threshold temperature includes the first temperature being equal to or higher than the second threshold temperature. The processor <NUM> may stop an operation of the compressor <NUM>, based on the temperature T_in measured by the first temperature sensor <NUM> reaching the second threshold temperature T* + δ and the operation frequency F1 of the compressor <NUM> reaching the predetermined minimum frequency F_min (<NUM>, <NUM>).

In another embodiment, referring to <FIG>, the processor <NUM> may check whether a temperature T_evain of refrigerant measured by the third temperature sensor <NUM> arranged on the inlet side of the evaporator <NUM> reaches a predetermined protection temperature Te (<NUM>). The temperature T_evain of the refrigerant reaching the protection temperature Te includes the temperature T_evain of the refrigerant being equal to or higher than the protection temperature Te. The processor <NUM> may stop the operation of the compressor <NUM>, based on the temperature T_evain of the refrigerant measured by the third temperature sensor <NUM> arranged on the inlet side of the evaporator <NUM> being equal to or higher than the predetermined protection temperature Te (<NUM>, <NUM>).

When the temperature T_evain of the refrigerant moving to the compressor <NUM> from the evaporator <NUM> is higher than a predetermined maximum temperature value, the compressor <NUM> may be damaged. Accordingly, when the temperature T_evain at the inlet of the evaporator reaches the protection temperature Te, the compressor <NUM> is forced to be off to protect the compressor <NUM>. The protection temperature Te may be equal to or lower than a predetermined maximum temperature of the refrigerant.

After a certain period of time elapses after the operation of the compressor <NUM> is stopped, the temperature T_in may be reduced below a third threshold temperature T* - α. The certain period of time may be predetermined and defined as a compressor stabilization time (e.g., <NUM> minutes). When the temperature T_in is reduced below the third threshold temperature T* - α, the processor <NUM> of the shoe care apparatus <NUM> may reoperate the compressor <NUM> (<NUM>, <NUM>). That is, when the temperature of the air supplied into the chamber <NUM> is lower than the target temperature due to an operation stoppage of the compressor <NUM>, control to maintain the target temperature may be performed by reoperating the compressor <NUM>.

The processor <NUM> may check an elapsed time (e.g., operation time) from the start of operation of the shoe care apparatus <NUM> and terminate the operation of the shoe care apparatus <NUM> when the operation time is expired (<NUM>, <NUM>).

The graph <NUM> of <FIG> illustrates a result of compressor switching control in an environment of a high outside air temperature To_H. According to the compressor switching control, it is confirmed that the temperature T_in of the air supplied into the chamber <NUM> is maintained within a predetermined range of the target temperature T*. In <FIG>, the compressor <NUM> operates at the maximum operation frequency F1_max to increase the temperature T_in of the air supplied into the chamber <NUM>. At the point in time ta1, the temperature T_in of the air supplied into the chamber <NUM> reaches the target temperature T*, and fuzzy control starts to maintain the target temperature T*. By the fuzzy control, the operation frequency F1 of the compressor <NUM> is reduced from the point in time ta1. Then, based on the evaporator inlet temperature T_evain reaching the protection temperature Te at a point in time tc, the compressor switching control starts. From the point in time tc, the compressor <NUM> is switched on or off.

<FIG> is a flowchart illustrating a control method of a second fan in a method of controlling a shoe care apparatus according to an embodiment. <FIG> is a graph <NUM> illustrating an example where an operating rate of a compressor is increased by an operation of a second fan. <FIG> is a graph <NUM> illustrating another example where an operating rate of a compressor is increased by an operation of a second fan.

Referring to <FIG>, the shoe care apparatus <NUM> starts operating (<NUM>), and the processor <NUM> may determine whether an outside air temperature is equal to or higher than a predetermined first operation temperature Tsc1 (<NUM>). The processor <NUM> may obtain temperature data from the second temperature sensor <NUM> located at the air outlet <NUM> of the chamber <NUM> in response to the start of operation of the shoe care apparatus <NUM>. The processor <NUM> may determine the outside air temperature based on the temperature measured by the second temperature sensor <NUM>.

Based on the outside air temperature being less than the predetermined first operation temperature Tsc1, the processor <NUM> may stop an operation of the second fan 47b or operate the second fan 47b at a predetermined rotation speed (e.g., a minimum rotation speed of <NUM> RPM) (<NUM>). Based on the outside air temperature being lower than the predetermined first operation temperature Tsc1, the temperature in the chamber <NUM> may be maintained at a target temperature without a decrease in an operating rate of the compressor <NUM>. Accordingly, the operation of the second fan 47b may be unnecessary. However, the second fan 47b may be operated to detect a failure in the second fan 47b and to stabilize a temperature in the machine room <NUM> including the compressor <NUM> before a start of a dry course.

The processor <NUM> may determine the start of operation of the second fan 47b based on the outside air temperature being equal to or higher than the first operation temperature, and may determine whether the outside air temperature is equal to or higher than a predetermined second operation temperature (<NUM>). The second operation temperature may be set in advance to be higher than the first operation temperature. For example, the first operation temperature may be set to <NUM> and the second operation temperature may be set to <NUM>. The processor <NUM> may determine a rotation speed of the second fan 47b based on whether the outside air temperature is equal to or higher than the predetermined second operation temperature.

The processor <NUM> may operate the second fan 47b at a first rotation speed (e.g., a base rotation speed of <NUM> RPM), based on the outside air temperature exceeding the first operation temperature and being less than the second operation temperature (<NUM>). On the contrary, the processor <NUM> may operate the second fan 47b at a second rotation speed (e.g., a maximum rotation speed of <NUM> RPM), based on the outside air temperature being equal to or higher than the second operation temperature (<NUM>). That is, the higher the outside air temperature, the higher the rotation speed of the second fan 47b may be set to.

As described above, compressor switching control for complementing a limit of fuzzy control may be performed to maintain the temperature in the chamber <NUM> at the target temperature.

The processor <NUM> may control the operation of the second fan 47b based on an operation state of the compressor <NUM>. For example, the processor <NUM> may increase the rotation speed of the second fan 47b in response to an operation stoppage of the compressor <NUM> (<NUM>, <NUM>). When the operation of the compressor <NUM> is not stopped, the rotation speed of the second fan 47b may be maintained without increasing. In addition, the processor <NUM> may reduce the rotation speed of the second fan 47b in response to resumption of the operation of the compressor <NUM> (<NUM>, <NUM>).

Meanwhile, despite the outside air temperature being lower than the first operation temperature Tsc1, the temperature T_in of the air supplied into the chamber <NUM> may exceed the target temperature T *. For example, when a high target temperature (e.g., a temperature higher than <NUM> and less than <NUM>) is set, the target temperature may not be maintained due to heat buildup inside the chamber <NUM> during the dry course. Accordingly, when the outside air temperature is lower than the first operation temperature Tsc1, the compressor switching control may be performed.

When the compressor <NUM> stops operating according to the compressor switching control, the compressor <NUM> and the first duct <NUM> may be cooled faster by increasing the rotation speed of the second fan 47b. When the compressor <NUM> and the first duct <NUM> are cooled rapidly, the temperature of the air supplied into the chamber <NUM> may also decrease more rapidly. When a period of time for the temperature of the air supplied into the chamber <NUM> to fall below the target temperature is shortened, a period of operation stoppage of the compressor <NUM> may also be shortened. As the period of operation stoppage of the compressor <NUM> decreases, the operation time of the compressor <NUM> may increase. Thus, the operating rate of the compressor <NUM> may be increased.

Based on expiration of the operation time of the shoe care apparatus <NUM> (<NUM>), the processor <NUM> may stop the operation of the second fan 47b and terminate the operation of the shoe care apparatus <NUM> (<NUM>).

Referring to the graph <NUM> of <FIG>, an example of a result of operating the second fan 47b is shown. Comparing the graph <NUM> of <FIG> with the graph <NUM> of <FIG>, it may be seen that the period of operation stoppage of the compressor <NUM> decreases and the operation time of the compressor <NUM> increases. That is, it may be seen that the operating rate of the compressor <NUM> increases by operating the second fan 47b.

Referring to the graph <NUM> of <FIG>, another example of a result of operating the second fan 47b is shown. Comparing the graph <NUM> of <FIG> with the graph <NUM> of <FIG>, it may be seen that the period of operation stoppage of the compressor <NUM> does not exist. That is, the temperature T_in of the air supplied into the chamber <NUM> may be maintained at the target temperature T * only by the fuzzy control without the compressor switching control, due to the operation of the second fan 47b.

<FIG> is a flowchart illustrating compressor current control in a method of controlling a shoe care apparatus according to an embodiment. <FIG> is a graph <NUM> illustrating an example of exceeding a limit current when a compressor current control is not applied during heat up. <FIG> is a graph <NUM> illustrating an example of a long heat up time when a compressor current control is not applied during heat up. <FIG> illustrates a current control table <NUM>. <FIG> is a graph <NUM> illustrating a result of compressor current control.

Referring to <FIG>, operation <NUM> is the same as described above. The processor <NUM> may operate the compressor <NUM> at the operation frequency F1 determined based on the target temperature T* and the outside air temperature To (<NUM>). The operation of the compressor <NUM> may cause the temperature of the air supplied into the chamber <NUM> to rise (<NUM>) (refer to <FIG>). To reduce a heat up time, the compressor <NUM> may operate at the maximum frequency F1_max.

Referring to the graph <NUM> of <FIG>, when a high target temperature T*_H is set in an environment of a low outside air temperature To_L, the compressor <NUM> may operate at the maximum frequency F1_max to rapidly increase the temperature T_in in the chamber <NUM>. In this case, a current applied to the compressor <NUM> may reach a limit current I_safe before the temperature T_in in the chamber <NUM> reaches the target temperature T*_H. That is, as shown in <FIG>, a point in time ta0 at which the compressor current reaches the limit current I_safe may be earlier than the point in time ta1 at which the temperature T_in in the chamber <NUM> reaches the target temperature T*_H.

The limit current I_safe may be defined as a maximum current that may operate the compressor <NUM> without damaging the compressor <NUM>. When the compressor current exceeds the limit current I_safe, a control circuit for controlling the compressor <NUM> may be damaged. Accordingly, to prevent damage to the control circuit due to application of an excessive current to the compressor <NUM>, the processor <NUM> may perform a compressor current control.

Meanwhile, an increase in the compressor current has the same meaning as an increase in instantaneous power consumed by the compressor <NUM>. That is, even when the instantaneous power of the compressor <NUM> exceeds limit power P_safe, the control circuit of the compressor <NUM> may be damaged.

Referring to the graph <NUM> of <FIG>, when the high target temperature T*_H is set in an environment of the low outside air temperature To_L, the current applied to the compressor <NUM> may be prevented from reaching the limit current I_safe before the temperature T_in in the chamber <NUM> reaches the target temperature T*_H by operating the compressor <NUM> at a normal frequency F1_N. However, there is a downside that it takes a longer time for the temperature T_in in the chamber <NUM> to reach the target temperature T*_H. Accordingly, a control method that may efficiently use the maximum frequency of the compressor without damaging the control circuit due to an excessive current is required.

Referring again to <FIG>, the processor <NUM> may control the operation frequency of the compressor <NUM> so that the compressor current is equal to or less than a predetermined limit current. The processor <NUM> may control the current applied to the compressor <NUM> by periodically controlling the operation frequency of the compressor <NUM>.

To this end, the processor <NUM> may check whether a compressor current I_comp reaches the limit current I_safe (<NUM>). The processor <NUM> may calculate a current difference Id between the limit current I_safe and the compressor current I_comp at predetermined intervals (<NUM>). The processor <NUM> may determine a control value Δfb of the operation frequency F1 by using a current control table <NUM> that may be pre-stored (<NUM>), and control the operation frequency based on the control value Δfb (<NUM>). Controlling of the operation frequency F1 to be applied to the compressor <NUM> may be performed by adding the control value Δfb to an operation frequency F1(n-<NUM>).

The processor <NUM> may determine the control value Δfb corresponding to the current difference Id by referring to the current control table <NUM>. The control value Δfb as mentioned in the current control may be referred to as a second control value. For example, in <FIG>, when the current difference Id is EA1, the control value Δfb may be determined as dfb3. That is, as the limit current I_safe is larger than the current compressor current I_comp by EA1, the compressor current may be increased to a larger value. When the operation frequency F1 of the compressor <NUM> is set to be higher than dfb3, the current applied to the compressor <NUM> increases.

Subsequently, when the temperature T_in reaches the first threshold temperature T* - λ (<NUM>), the aforementioned fuzzy control may be started.

Referring to the graph <NUM> of <FIG>, when an outside air temperature is a low temperature To_L and the target temperature is set to a medium value T*_M, the operation frequency of the compressor <NUM> is set to a high value F1_H. Also, because the compressor current reaches the limit current I_safe at the point in time ta0 before the temperature T_in in the chamber <NUM> reaches the target temperature T*_H at the point in time ta1, current control of the compressor <NUM> is performed. When the temperature T_in of the air flowing into the chamber <NUM> reaches the first threshold temperature lower than the target temperature T*_M, the processor <NUM> of the shoe care apparatus <NUM> performs fuzzy control to maintain the temperature in the chamber <NUM>.

Through the above current control, the maximum frequency of the compressor may be efficiently used without damaging the control circuit due to an excessive current. Accordingly, the heat up time of the air supplied into the chamber may be reduced.

<FIG> is a table <NUM> illustrating embodiments where the operation frequency of the compressor is controlled based on an outside air temperature and a target temperature.

Referring to the table <NUM> of <FIG>, an outside air temperature may be divided into multiple sections. For example, the outside air temperature may be divided into low temperature, room temperature and high temperature. The low temperature may be lower than <NUM>, the room temperature may be <NUM> or higher and <NUM> or lower, and the high temperature may exceed <NUM>. Alternatively, the outside air temperature may be subdivided into more sections.

The target temperature may be divided into multiple sections as well. For example, the target temperature may be divided into low target temperature, medium target temperature and high target temperature. The low target temperature may be <NUM> or higher and <NUM> or lower, the medium target temperature may be <NUM> or higher and <NUM> or lower, and the high target temperature may be <NUM> or higher and <NUM> or lower. Alternatively, the target temperature may be subdivided into more sections.

As the target temperature requires to be maintained regardless of changes in the outside air temperature and the target temperature, all the embodiments include fuzzy control in common for maintaining the temperature in the chamber <NUM> at the target temperature.

In an environment having a low outside air temperature, the operation frequency F1 of the compressor <NUM> may be set to a high value F1_H. The high value F1_H may refer to the maximum frequency F1_max of the compressor <NUM>. This is to reduce the heat up time. When the outside air temperature is low and the target temperature is set to a medium value or higher, current control for controlling the operation frequency of the compressor <NUM> may be performed. It is because the compressor current may reach the limit current before the temperature in the chamber <NUM> reaches the target temperature.

In an environment in which the outside air temperature is the room temperature, the operation frequency F1 of the compressor <NUM> may be set to a normal value F1_N.

When the target temperature is set to have a high value, when the outside air temperature is high, or when the outside air temperature is high and the target temperature has a high value, the compressor switching control may be performed to prevent the temperature in the chamber <NUM> from exceeding the target temperature or to protect the compressor <NUM>.

When a difference between the target temperature and the outside air temperature is small (e.g., when the difference between the target temperature and the outside air temperature is <NUM> or less), the operation frequency of the compressor <NUM> may be set to a low value F1_L in order to prevent the temperature in the chamber <NUM> from exceeding the target temperature in the heat up section. In the table <NUM>, illustrated is an example where the operation frequency of the compressor <NUM> is set to the low value F1_L when the outside air temperature is high and the target temperature is set to a low value or a medium value.

When the outside air temperature is high and the target temperature has a high value, the operation frequency of the compressor <NUM> may be determined as the normal value F1_N.

Furthermore, as there may be a difference between the temperature of the shoes and the outside air temperature, compensation of the target temperature and compensation of the operation time may be performed. For example, in an environment having a low outside air temperature, compensation of the target temperature and compensation of the operation time may be performed positively. It is because the environment having the low outside air temperature requires more heat up time. On the other hand, in an environment having a high outside air temperature, compensation of the target temperature and compensation of the operation time may be performed negatively. As such, more precise temperature control may be implemented by performing compensation of the target temperature and compensation of the operation time.

As described above, the shoe care apparatus and the method of controlling the same can increase an operating rate of the compressor, even in a high outside air temperature environment. As the operating rate of the compressor increases, an actual time for dehumidification can increase, an overall operation time of the shoe care apparatus can be reduced, and a usable temperature range of the shoe care apparatus can be extended. Accordingly, a dehumidification performance of the shoe care apparatus can be improved.

The shoe care apparatus and the method of controlling the same can also reduce a heat up time of the air in the chamber by efficiently using a maximum frequency of the compressor without damaging a control circuit due to excessive current.

Meanwhile, the disclosed embodiments may be embodied in the form of recording medium storing instructions executable by a computer. The instructions may be stored in the form of program code and, when executed by a processor, may generate a program module to perform the operations of the disclosed embodiments.

The term "non-transitory storage medium" may mean a tangible device without including a signal, e.g., electromagnetic waves, and may not distinguish between storing data in the storage medium semi-permanently and temporarily. For example, the non-transitory storage medium may include a buffer that temporarily stores data.

Claim 1:
A shoe care apparatus (<NUM>), comprising:
a chamber (<NUM>) comprising an air inlet (<NUM>) and an air outlet (<NUM>);
a first duct (<NUM>) connected to the air outlet (<NUM>);
an evaporator (<NUM>) inside the first duct (<NUM>);
a condenser (<NUM>) inside the first duct (<NUM>);
a second duct (<NUM>) connecting the first duct (<NUM>) to the air inlet (<NUM>);
a holder (<NUM>) in the chamber (<NUM>) and connected to the air inlet (<NUM>);
a first fan (47a) configured to circulate air through the first duct (<NUM>), the second duct (<NUM>), the holder (<NUM>), and the chamber (<NUM>);
a compressor (<NUM>) inside a machine room (<NUM>) of the shoe care apparatus (<NUM>), the compressor (<NUM>) separated from the chamber (<NUM>) and the first duct (<NUM>) and configured to discharge a refrigerant to the condenser (<NUM>);
a second fan (47b) inside the machine room (<NUM>), and configured to allow air in the machine room (<NUM>) to flow;
a temperature sensor (<NUM>); and
a processor (<NUM>),
characterized in that the temperature sensor (<NUM>) is configured to measure an outside air temperature and the processor (<NUM>) is configured to control an operation of the second fan (47b) based on the outside air temperature and an operation state of the compressor (<NUM>) and the processor is configured to perform fuzzy control to control the operating frequency of the compressor (<NUM>) so that a temperature of the air heated by the condenser (<NUM>) follows a target temperature.