AU2013245540B2

AU2013245540B2 - Laundry machine

Info

Publication number: AU2013245540B2
Application number: AU2013245540A
Authority: AU
Inventors: Seungphyo Ahn; Seonghwan Kim; Hyunwoo Noh
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2012-10-22
Filing date: 2013-10-18
Publication date: 2015-12-03
Anticipated expiration: 2033-10-18
Also published as: DE202013104695U1; EP2725133A2; EP2725133A3; BR102013026927A2; US20140109428A1; KR20140050980A; EP2725133B1; AU2013245540A1; KR101989522B1; CN103774402A; BR102013026927B1; CN103774402B

Abstract

The present disclosure relates to a heat pump type clothes dryer for enhancing extra-cooling performance using condensation water, and relates to a 5 clothes dryer in which a second condenser is added to a first condenser in the clothes dryer employing a heat pump to maximize a condensation effect so as to enhance heat exchange efficiency, and moreover, condensation water generated from the heat exchanger unit is used for the cooling of the second condenser to, improve the condensation effect. 10 Accordingly, the clothes dryer of the present disclosure may be a circulation type heat pump clothes dryer including a cabinet, a drum, a drying duct configured to circulate dry air by resupplying it thereto, an evaporator having a heat pump, a condenser, a compressor and an expansion apparatus, wherein the condenser includes a first condenser configured to liquefy a high-temperature and 15 high-pressure refrigerant circulated from the compressor; and a second condenser configured to condense the refrigerant condensed from the first condenser again, and the second condenser is formed below a condensation water surface accumulated at a lower portion of the drying duct at a lower portion of the first condenser to cool the second condenser using condensation water produced by 20 the evaporator. 120 10 180 15

Description

Australian Patents Act 1990 - Regulation 3.2 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title Laundry machine The following statement is a full description of this invention, including the best method of performing it known to me/us:- H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 -1A TECHNICAL FIELD The present disclosure generally relates to a clothes dryer, e.g., a combined washing and drying machine or a clothes dryer, e.g., a heat pump type laundry machine for 5 enhancing dehumidifying power in an evaporator using condensation water. BACKGROUND In general, a laundry machine includes a clothes treating apparatus, such as a washing machine, a washer, a combined washing and drying machine or a dryer. The 10 laundry machine having a drying function, such as a combined washer or a dryer is a device wherein the laundry is in the drum in a state that the washing is completed and a dehydration process is performed, supplying hot air into the drum to evaporate moisture of the laundry, thereby drying the laundry. For an example of a dryer of them, the foregoing dryer may include a drum 15 rotatably provided within a cabinet to put the laundry thereinto, a drive motor configured to drive the drum, a blower fan configured to blow air into the drum, and a heating means configured to heat air brought into the drum. Furthermore, the heating means may use high-temperature electric resistance heat generated using an electric resistance, or combustion heat generated by combusting gas. 20 On the other hand, air discharged from the drum contains the moisture of the laundry, and thus becomes high temperature and humid air. Here, the dryer may be classified according to a method for processing the high temperature and humid air, and thus divided into a condensation (circulation) type dryer for condensing moisture contained in the high temperature and humid air by cooling the air below the dew point temperature through a condenser while being circulated without discharging the high temperature and 5 humid air out of the dryer, and an exhaustion type dryer for directly discharging the high temperature and humid air having passed through the drum to the outside. In case of the condensation type dryer, in order to condense air discharged from the drum, the process of cooling the air below the dew point temperature should be carried out to heat the air through the heating means prior 10 to being supplied to the drum again. Here, the loss of heat energy contained in the air is generated while being cooled down during the condensation process, and an additional heater or the like is required to heat the air to a temperature required for drying. Even in case of the exhaustion type dryer, it is required to discharge high 15 temperature and humid air to the outside and receive outside air at normal temperature, thereby heating the air up to a required temperature level through the heating means. In particular, thermal energy transferred by the heating means is contained in high temperature air being discharged to the outside but it is discharged and wasted to the outside, thereby reducing the thermal efficiency. 20 Accordingly, in recent years, clothes treating apparatuses for collecting energy required to generate hot air and energy being discharged to the outside without being used have been introduced to increase energy efficiency, and a clothes treating apparatus having a heat pump system has been introduced as an example of the clothes treating apparatus. The heat pump system may include two 25 heat exchangers, a compressor and an expansion apparatus, and energy 2 H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 -3 contained in the discharged hot air is reused in heating up air being supplied to the drum, thereby increasing energy efficiency. Specifically, in the heat pump system, an evaporator is provided at the exhaust side, and a condenser at an inlet side of the drum, and thus thermal energy is transferred to 5 refrigerant through the evaporator and then thermal energy contained in the refrigerant is transferred to air brought into the drum, thereby generating hot air using waste energy. However, in a dryer using such a typical heat pump, the size of the condenser may be restricted due to a lack of space within which the condenser is installed, thereby causing difficulty in achieving its condensation effect. 10 Accordingly, heat exchange efficiency may be reduced in the heat exchanger and the cooling of refrigerant may not be properly carried out, thereby reducing dehumidifying capability. It is desired to address or ameliorate one or more disadvantages or limitations associated with the prior art, or to at least provide a useful alternative. 15 SUMMARY In accordance with the present invention there is provided a clothes dryer, comprising: a rotatable drum; 20 a drying duct configured to circulate air discharged from the drum by resupplying it thereto; an evaporator and a condenser sequentially provided on a flow path formed by the drying duct; and a compressor and an expansion apparatus configured to form a refrigerant cycle 25 along with the evaporator and the condenser, wherein the condenser comprises a first condenser part configured to liquefy a refrigerant circulated from the compressor; and a second condenser part configured to condense the refrigerant condensed from the first condenser part again, and wherein the second condenser part is arranged below a condensation water line at 30 a lower portion of the drying duct for cooling the second condenser using condensation water.

H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 -4 The present invention also provides a clothes dryer having a rotatable drum for drying clothes placed therein, a drying duct arranged in an air flow path including the drum for circulation of drying air around the air flow path and through the drum, a heat pump arranged for dehumidifying air from the drum and flowing on said air flow path, the heat 5 pump having a first condenser configured to liquefy refrigerant circulated from a compressor of the heat pump, and a second condenser configured to condense again the refrigerant condensed from the first condenser, the second condenser being positioned to be cooled by condensation water recovered from said air by an evaporator of said heat pump pursuant to said dehumidification. 10 BRIEF DESCRIPTION OF THE DRAWINGS Some embodiments of the present invention are hereinafter described, by way of non-limiting example only, with reference to the accompanying drawings, in which: FIG. 1 is a schematic view illustrating the internal structure of a laundry machine of 15 the present disclosure; FIG. 2 is a partial detail view illustrating a circulation type heat pump within a laundry machine of the present disclosure; FIG. 3 is a structural view illustrating the drying method of the heat pump; FIG. 4 is a structural view illustrating the circulation path of a refrigerant using a 20 second condenser according to the present disclosure; FIG. 5 is a view illustrating dryer air passing through the evaporator and condenser according to the related art; FIG. 6 is a view illustrating a second condenser according to another embodiment of the present disclosure; and 25 FIG. 7 is a view illustrating a second condenser according to still another embodiment of the present disclosure. DETAILED DESCRIPTION Described herein is a clothes dryer, comprising: 30 a rotatable drum; H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 - 4A a drying duct configured to circulate air discharged from the drum by resupplying it thereto; an evaporator and a condenser sequentially provided on a flow path formed by the drying duct; and 5 a compressor and an expansion apparatus configured to form a refrigerant cycle along with the evaporator and the condenser, wherein the condenser comprises a first condenser part configured to liquefy a refrigerant circulated from the compressor; and a second condenser part configured to condense the refrigerant condensed from the first condenser part again, and 10 wherein the second condenser part is arranged below a condensation water line at a lower portion of the drying duct for cooling the second condenser using condensation water. Described herein is a clothes dryer having a rotatable drum for drying clothes placed therein, a drying duct arranged in an air flow path including the drum, for 15 circulation of drying air around the path and through the drum, a heat pump arranged for dehumidifying air from the drum and flowing on said path, the heat pump having a first condenser configured to liquefy refrigerant circulated from a compressor of the heat pump, and a second condenser configured to condense again the refrigerant condensed from the first condenser, the second condenser being positioned to be cooled by condensation water 20 recovered from said air by an evaporator of said heat pump pursuant to said dehumidification. The addition of the second condenser to the first condenser may maximize a condensation effect, thereby enhancing heat exchange efficiency. Embodiments described herein employ a heat pump structure in which refrigerant 25 is extra-cooled, e.g. supercooled, for the cooling of the second condenser during the refrigerant cycle using condensation water generated from the heat exchanger unit, thereby enhancing dehumidifying capability. In embodiments described herein, a heat pump structure is employed in which the second condenser itself has a separate independent condenser structure being submerged 30 under condensation water, thereby removing a cooling fan that has been required for the use of a extra-cooling period. According to an embodiment of the present disclosure, a clothes dryer of the present disclosure may include a cabinet; a drum rotatably provided within the cabinet; a drying duct provided in the cabinet to circulate air discharged from the 5 drum by resupplying it thereto; an evaporator and a condenser sequentially provided on a flow path formed by the drying duct; and a compressor and an expansion apparatus configured to form a refrigerant cycle along with the evaporator and the condenser, wherein a part of the condenser is arranged below a condensation water line of the drying duct. 10 Furthermore, the condenser may include a first condenser part or first condenser configured to liquefy a high-temperature and high-pressure refrigerant circulated from the compressor. A second condenser part or second condenser may be further provided and configured to condense the refrigerant condensed from the first condenser part again to extra-cool refrigerant during the refrigerant 15 cycle, thereby enhancing dehumidifying capability in the evaporator. A lower portion of the drying duct may be configured to accumulate condensation water from the evaporator up to a condensation water line for cooling the second condenser. Preferably, the second condenser is formed at the lower portion of the drying duct below the condensation water line. Accordingly, 20 the second condenser may be formed below a condensation water line at a lower portion of the drying duct and/or at a lower portion of the first condenser to cool the second condenser using condensation water condensed at the evaporator. The second condenser may be formed as a refrigerant line extended from the first condenser and integrally formed therewith. For instance, a refrigerant pipe of the 25 second condenser may be formed to be extended from a refrigerant pipe of the 5 first condenser. The condensation water line refers to a level in the drying duct, to which condensation water normally fills up. The refrigerant pipe of the first condenser and the refrigerant pipe of the second condenser may be intrusively formed in the same heat dissipation fins, e.g. 5 penetrating the same heat dissipation fins. Furthermore, the refrigerant pipe of the first condenser may be vertically arranged, e.g. in a meandering pattern or in a zigzag pattern. Here, the lowest end portions or lower bends of the refrigerant pipe of the first condenser may be disposed above the condensation water line. Alternatively, the refrigerant pipe of io the first condenser may be horizontally arranged, e.g. in a meandering pattern or in zigzag pattern. Then, the lowest column or level of the refrigerant pipe of the first condenser may be disposed on the condensation water line. The refrigerant pipe of the second condenser may be horizontally arranged, e.g. in a meandering pattern or in a zigzag pattern, below the 15 condensation water line. The refrigerant pipe of the second condenser may be disposed below the condensation water line, e.g. extended from the lowest end portion or lowest column of the refrigerant pipe of the first condenser to be arranged below the condensation water line. According to another embodiment of the present disclosure, the second 20 condenser may include an independent refrigerant line separated from the first condenser. This independent refrigerant line of the second condenser may be disposed below a condensation water line at a lower portion of the drying duct to cool the second condenser using condensation water condensed at the evaporator. In the foregoing embodiment, at least one heat dissipation fin of the first 25 condenser may be configured as an independent heat dissipation fin separated 6 from the heat dissipation fin(s) of the second condenser. Preferably, the heat dissipation fins of the first condenser and the heat dissipation fin of the second condenser are formed separately from each other, respectively. In addition, a refrigerant pipe of the first condenser may be vertically 5 arranged in a zigzag pattern, and the lowest end portion of a refrigerant pipe of the first condenser may be disposed on or above the condensation water line, and the refrigerant pipe of the second condenser may be horizontally arranged in a zigzag pattern below the condensation water line. The first condenser and the second condenser may be connected by a io refrigerant circulation line as a whole. Here, a heater for reheating air that has been heated up while passing through the evaporator may be additionally provided therein. The heater may be included in an intake duct for providing heated air to the drum. According to embodiments of the present disclosure, the following effects 15 can be promoted by the foregoing task solving means, and the configurations, combinations, and working relations which will be described later. According to the present disclosure, a second condenser may be added to a first condenser in a clothes dryer employing a circulation type heat pump to maximize a condensation effect, thereby enhancing heat exchange efficiency. 20 Moreover, according to the present disclosure, refrigerant may be extra cooled for the cooling of the second condenser during the refrigerant cycle using condensation water generated from the heat exchanger unit, thereby enhancing dehumidifying capability. According to the present disclosure, furthermore, the second condenser 25 itself may have a separate independent condenser structure configured to be 7 H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 submerged under condensation water. By these means, a cooling fan can be removed that has been required for the use of a extra-cooling period, thus saving an additional space for the cooling fan, and increasing space efficiency. Hereinafter, a heat pump type dryer according to some embodiments of the present 5 disclosure will be described in detail with reference to the accompanying drawings. The dryer is only one example of a laundry machine according to the embodiments. The same can be applied to a combined washing and drying machine and the like. Accordingly, since the embodiments described in the present disclosure and configurations shown in the drawings are embodiments only and do not represent all of 10 technical concept of the invention, it should be understood that there may be various equivalents and modification examples that may replace them at the time of application of present disclosure.

H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 -9 Hereinafter, the configurations and working relations of a clothes dryer as an example for a laundry machine according to the present disclosure will be described in detail with reference to the accompanying drawings. FIGS. 1 and 2 are views illustrating the internal structure of a heat pump type dryer, 5 and FIG. 3 is a block diagram illustrating the drying method of the heat pump. Furthermore, FIG. 4 is a view illustrating the circulation path of a refrigerant using a second condenser according to the present disclosure, and FIG. 5 is a view illustrating dryer air passing through the evaporator and condenser according to the related art. Furthermore, FIGS. 6 and 7 are views illustrating a second condenser according to other embodiments of the present disclosure. Referring to FIGS. 1 through 3, the present disclosure may include a 5 cabinet 100 forming the outside of the clothes dryer, and a drum 110 rotatably provided within the cabinet. The drum is rotatably supported by a supporter (not shown) at the front and rear sides thereof and may be driven by a motor 10. An intake duct 170 provided in the cabinet to inhale outside air and supply the air to an inner portion of the drum is provided in the vertical direction of the 10 drum at the rear side of the drum. An intake flow path through which the air inhaled into the drum flows is formed by the intake duct. According to the present disclosure, the air inhaled through the intake duct may be brought in from the outside of the cabinet separately from the drying duct 190. On the other hand, a heater 180 for heating the inhaled air to become high 15 temperature air required for drying the laundry may be provided within the intake duct 170. The heater 180 receives electrical energy to sufficiently and quickly heat air to be supplied to the drum, and further supplies heating such that the refrigerant cycle is stably managed in a normal state. By there means, power efficiency of a heat pump type laundry machine can be improved and overload of 20 the heat pump can be avoided. According to the foregoing structure, heating required for drying can be sufficiently supplied in a short period of time, thereby having an effect of reducing dry time. In other words, additional heating can be supplied in a short period of time since the heating cannot be sufficiently supplied in a short period of time 25 using only air on the circulation flow path with the drying duct. 10 The air brought into the drum may be supplied through a circulation flow path formed in the drying duct 190 separately from the air through the intake flow path. The drying duct 190 is provided in the cabinet to circulate air discharged from the drum by resupplying it thereto. 5 The air brought into the drum dries the laundry and then is brought into a front surface duct (not shown) located at a lower front side of the drum and supplied to the drum again through the drying duct by way of a lint filter (not shown) or discharged to the outside of the cabinet through an exhaust duct which will be described later. 10 A blower fan 120 for inhaling air within the drum to forcibly blow it to the outside of the dryer may be provided on the circulation flow path of the drying duct. Here, an evaporator 130 and a condenser 140 are sequentially provided on a flow path formed by the drying duct. The evaporator 130 and condenser 140 as a kind of heat exchanger, according to the present disclosure, form a refrigerant 15 cycle of the heat pump, thereby achieving heat exchange with air (Ad) on the circulation flow path by refrigerant flowing thereinside. The air brought into the drum is heated by the heater 180 on the intake flow path or the condenser 140 on the circulation flow to become high-temperature dry air at about 150-250 0C when being brought into the drum. The high 20 temperature air is brought into contact with an object to be dried to evaporate the moisture of the object to be dried. The evaporated moisture is to be contained in middle-temperature air and exhausted out of the drum. At this time, in order to circulate the middle temperature and humid air and reuse it, the moisture should be removed. Since the moisture content in the air is affected by the temperature, 25 the moisture can be removed when cooling the air. Accordingly, the air on the 11 circulation flow path is cooled by heat exchange with the evaporator 130. In order to supply the air cooled by the evaporator 130 again to the drum, it should be heated by high temperature air, and the heating of the air is carried out by the condenser 140. 5 A refrigerant cycle performs heat exchange with the environment using the phase change of refrigerant flowing through the inside thereof. Briefly described, refrigerant is transformed into a low-temperature and low-pressure gas by absorbing heat from the environment in the evaporator, compressed into a high temperature and high-pressure gas in the compressor, transformed into a high 10 temperature and high-pressure liquid by dissipating heat to the environment in the condenser, transformed into a low-temperature and low-pressure liquid by dropping its pressure in the expansion apparatus, and brought into the evaporator again. Due to the circulation of refrigerant, heat is absorbed from the environment in the evaporator and heat is supplied to the environment in the condenser. The 15 refrigerant cycle may be also referred to as a heat pump. According to the present disclosure, the refrigerant cycle may include the compressor 150 and expansion apparatus 160 along with the evaporator 130 and condenser 140. The flow path of air in heat exchange with the refrigerant cycle is 20 illustrated in FIGS. 2 and 3. In other words, an arrow passing through the evaporator and condenser and a line connecting between the evaporator and condenser does not indicate the flow path of the refrigerant but indicate the flow path of the air in FIGS. 2 and 3, and the air is sequentially brought into contact with the evaporator and the like to perform heat exchange. 25 For the configuration in more detail, as illustrated in FIG. 3, it is seen that 12 the evaporator 130 and condenser 140 are sequentially disposed, respectively, on the circulation flow path (a large circulation line formed along a bold arrow in FIG. 3) formed by the drying duct 190. As illustrated in FIG. 3, the air (Ad) on the circulation flow path performs 5 heat exchange with the heat pump during the refrigerant cycle, specifically the air (Ad) on the circulation flow path dissipates heat in heat exchange with the evaporator, and absorbs heat in heat exchange with the condenser. As a result, the air on the circulation flow path absorbs heat dissipated by itself again. In general, the evaporator and condenser are mainly in charge of heat io exchange during the refrigerant cycle, and the air from which heat is taken in the evaporator liquefies moisture contained therein to exhaust it as condensation water, and dry air is heated by the compressor and condenser to be changed into high temperature and dry air. In this manner, the air changed into high-temperature air in heat exchange 15 with the refrigerant cycle through the circulation flow path is brought into the drum along with the air into the intake flow path to participate in the drying process. Here, part of the air brought into the drum and used in the drying process is exhausted to the outside of the dryer, and part thereof is reused, and supplied to the air reused by absorbing only part of waste heat using the refrigerant cycle. 20 However, the embodiments of the present invention may also be employed in a circulation type dryer without exhausting air or in an exhaustion type dryer, in which all of the air is exhausted to the outside of the dryer. In the heat pump type clothes dryer, waste heat is typically collected using the refrigerant cycle, and the present disclosure provides an optimization means 25 not to cause a overload during the refrigerant cycle. In other words, in case of a 13 refrigerant cycle, the heat exchange of refrigerant should be carried out by phase change at the optimal operating temperature and pressure, and to this end, an heat exchanger such as an evaporator and a condenser, a compressor, an expansion apparatus and the like are used. Accordingly, in order to collect more 5 heat, the size of the heat exchanger or compressor is inevitably increased. However, in case of a typical clothes dryer, it has a spatial restriction and thus the heat exchanger, compressor or the like is limited in their size. Accordingly, according to the present disclosure, the heater 180 for heating the inhaled air to become high-temperature air required for drying the 10 laundry is provided within the intake duct to continuously replenish the inhaled air with heating. According to the present disclosure, heating may be replenished through the heater 180 to sufficiently supply the heating required for drying, thereby reducing dry time. Furthermore, in case of a refrigerant cycle, the heat exchange 15 of refrigerant should be carried out by a phase change at the optimal operating temperature and pressure, and to this end, heating should be sufficiently supplied. Otherwise, it may cause a problem such as refrigerant being supplied to the compressor in a liquid phase or the like, and thus the cycle cannot be stably operated, thereby reducing the reliability of the cycle. Accordingly, as disclosed 20 herein, the air brought into the drum may be additionally replenished with heating by the heater 180, and thus it is preferable that the refrigerant cycle can be stably operated in a normal state. In addition, an additional blower fan 120 may be provided on the intake flow path to provide more airflow. Furthermore, the additional blower fan provides 25 more airflow and thus the heater 180 is not overheated on the intake flow path. 14 The configuration provided with the additional blower fan 120 is illustrated in FIGS. 2 through 4. On the other hand, the present disclosure may be configured such that part of the air is exhausted to the outside of the cabinet at the upstream of the 5 evaporator on the circulation flow path. Accordingly, as illustrated in FIG. 1, the present disclosure may further include an exhaust duct 15 branched from the upstream of the evaporator 130 in the drying duct 190, and the exhaust duct is configured to exhaust part of the air to the outside of the cabinet at the upstream of the evaporator on the circulation flow path. The exhaust duct forms an exhaust 10 flow path for discharging hot air coming out of the drum to exhaust part of the air to the outside of the cabinet. According to the foregoing configuration, waste heat is absorbed from part of the middle temperature and humid air coming out of the drum only within a range that can be processed by the refrigerant cycle, and the rest of the air is 15 exhausted. Accordingly, it may be possible to reduce energy waste as well as not to cause an overload during the refrigerant cycle. Furthermore, it may be possible to reduce power consumption as well as enhance reliability for the operation of the refrigerant cycle. Hereinafter, a heat pump type clothes dryer for maximizing a condensation 20 effect using a second condenser according to the present disclosure to enhance dehumidifying capability will be described with reference to FIGS. 4 through 7. Referring to FIG. 4, a clothes dryer according to the present disclosure may include an evaporator 130, a condenser 140, a compressor 150 and an expansion apparatus 160 as a heat pump type dryer. It has been sufficiently 25 described in the above, and thus the description thereof will be omitted below. 15 According to the present disclosure, the condenser 140 may include a first condenser part or first condenser 140 configured to liquefy a high-temperature and high-pressure refrigerant circulated from the compressor; and a second condenser or a second condensing unit 141 configured to condense the refrigerant 5 condensed from the first condenser again to extra-cool refrigerant during the refrigerant cycle, thereby enhancing dehumidifying capability in the evaporator. Typically, refrigerant passes through the compressor 150 to follow the path of the condenser 140, expansion apparatus 160 and evaporator 130, and according to the present disclosure, a separate second condensing unit 141 may io be included therein when refrigerant that has passed through the compressor 150 is condensed in the condenser 140, thereby enhancing the condensation effect. As described above, the level of extra-cooling may be further increased through the first condenser 140 and second condensing unit 141 in the condenser to enhance dehumidifying capability in the evaporator, thereby increasing the 15 efficiency of the heat pump. Furthermore, the second condensing unit 141 may further include a cooling fan 146 for enhancing the extra-cooling performance of a second condenser 143 in addition to the second condenser 143 separately provided therein. The cooling fan 146 may inhale external air at ambient temperature to 20 cool the second condenser 143. Here, for the refrigerant cycle of the heat pump dryer, refrigerant flowing into the pipe from the outlet of the condenser passes through the second condenser before passing through the expansion apparatus (or expansion valve) to enhance dehumidifying capability in the evaporator for removing moisture in the 25 dry flow path. Accordingly, it has a structure in which refrigerant in the second 16 condenser 143 is further extra-cooled and brought into the evaporator in a low refrigerant dryness state through the expansion apparatus (e.g. an expansion valve), thereby enhancing dehumidifying capability. However, according to the foregoing embodiment, a separate cooling fan 5 as well as the second condenser and connecting pipe should be additionally provided to increase the extra-cooling of refrigerant, thereby causing an increase in the raw material cost of the product. Consequently, according to another embodiment of the present disclosure, as illustrated in FIG. 6, the second condenser 148 is formed below a condensation io water line at a lower portion of the drying duct as a refrigerant line extended from the first condenser and integrally formed therein. Furthermore, the second condenser is cooled using condensation water, which is a water condensed at the evaporator. In FIG. 5, a conventional heat pump structure comprising an evaporator 15 130 and a condenser 140 in a drying duct is shown. The evaporator 130 and the condenser 140 are arranged at the same height and above the condensation water line WL of the drying duct, up to which condensation water W is collected. The refrigerant lines or refrigerant pipes PE and Pc of the evaporator 130 and the condenser 140 are connected to each other via the compressor 150. 20 Referring to FIG. 6, according to an embodiment of the present disclosure, the refrigerant pipe of the first condenser 140 and the refrigerant pipe of the second condenser are intrusively formed in the same heat dissipation fins. Here, considering the arrangement of the first condenser and second condenser inserted into one or more the heat dissipation fins, the refrigerant pipe 25 Pc 1 of the first condenser is vertically arranged in a zigzag or meandering pattern, 17 and the lowest end portion of the refrigerant pipe thereof is arranged on or above a condensation water line WL, and the refrigerant pipe PC 2 of the second condenser 148 is horizontally arranged below the condensation water line. Vertically or horizontally arranged respectively refers to a plurality of subsequent 5 bends of the refrigerant pipe of the condenser being arranged in a vertical or horizontal plane with respect to the installed condenser. Vertical or horizontal may thus refer to the main flow direction of the refrigerant in the refrigerant pipe. Accordingly, the condenser 140 may not be required to be cooled with a separate cooling fan for the cooling of the condenser, and space utilization is 10 enhanced, thereby promoting economical efficiency. According to the foregoing embodiment, the second condenser 148 can be considered as a partial lower portion of the condenser 140 being submerged under condensation water (W), and the relevant lower portion of the condenser 15 exhibits a structure for enhancing the extra-cooling efficiency of the condenser using the condensation water. Accordingly, a rear end portion at the outlet side of the pipe coming out of the condenser 148 should be submerged under condensation water to achieve extra-cooling without reducing the performance of the condenser. 20 Considering another embodiment of the present disclosure with reference to FIG. 7, the second condenser 148 is disposed below a condensation water line at a lower portion of the drying duct as an independent refrigerant line separated from the first condenser 140 to cool the second condenser using condensation water generated by the evaporator. 25 As illustrated in FIG. 7, the at least one heat dissipation fin of the first 18 condenser 140 and the at least one heat dissipation fin of the second condenser 149 may be configured as independent heat dissipation fins separated from each other, respectively. 5 According to an embodiment in FIG. 7, the refrigerant circulation line (Pc1) in the first condenser and the refrigerant circulation line (Pc2) in the second condenser may be preferably connected by a separate refrigerant circulation line that does not penetrate the heat dissipation fin. Accordingly, referring to FIG. 7, refrigerant (Pc1) circulated from the io compressor (not shown in the drawing) is all circulated through the condenser 140, and then circulated again through the second condenser 149 via a separate refrigerant circulation path. Here, the refrigerant circulation (Pc2) of the second condenser 149 may be submerged under the surface of condensation water (W), i.e. below the 15 condensation water line (WL) of the drying duct. According to the present configuration, an additional cooling fan according to the foregoing embodiment may be provided to one or both of the condenser parts in order to maximize cooling efficiency. However, a cooling function can already be promoted through condensation water (W) produced by the evaporator 130 without having an 20 additional cooling fan according to the present embodiment, thereby avoiding an additional configuration as well as maximizing space utilization. Accordingly, it is preferable that the refrigerant pipe Pc 1 of the first condenser 140 is vertically arranged, e.g. in a zigzag pattern, and the lowest end portion of the refrigerant pipe Pc 1 is disposed not to be brought into contact with 25 condensation water on the condensation water line (WL), and the refrigerant pipe 19 H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 - 20 PC2 of the second condenser is horizontally arranged below the condensation water line, e.g. in a zigzag pattern, to be submerged under condensation water. Consequently, according to the present embodiment, the second condenser itself has a separate independent condenser structure and the second condenser has a structure 5 being submerged under condensation water. Accordingly, refrigerant that has passed through the condenser may be extra-cooled while being circulated through the second condenser submerged under condensation water, and as a result, a cooling fan that has been required for the use of a extra-cooling period in the foregoing embodiment is not required, and the cost is reduced and an additional space is not occupied, thereby 10 increasing space efficiency. The clothes dryer can be referred to as a heat pump type clothes dryer for enhancing extra-cooling performance using condensation water. It should be understood by those skilled in the art that various substitutions, modifications and changes can be made without departing from the scope of the invention.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or 5 group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior io publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavor to which this specification relates. 21

Claims

1. A clothes dryer, comprising: a rotatable drum; a drying duct configured to circulate air discharged from the drum by resupplying it thereto; an evaporator and a condenser sequentially provided on a flow path formed by the drying duct; and a compressor and an expansion apparatus configured to form a refrigerant cycle along with the evaporator and the condenser, wherein the condenser comprises a first condenser part configured to liquefy a refrigerant circulated from the compressor; and a second condenser part configured to condense the refrigerant condensed from the first condenser part again, and wherein the second condenser part is arranged below a condensation water line at a lower portion of the drying duct for cooling the second condenser using condensation water.

2. The clothes dryer of claim 1, wherein the second condenser part is arranged at a lower portion of the first condenser part.

3. The clothes dryer of claim 1 or 2, wherein the lower portion of the drying duct is configured to accumulate condensation water from the evaporator for cooling the second condenser part.

4. The clothes dryer according to any one of the preceding claims, wherein a refrigerant pipe of the first condenser part is vertically and/or horizontally arranged in a zigzag pattern.

5. The clothes dryer according to any one of the preceding claims, wherein a refrigerant pipe of the second condenser part is horizontally arranged in a zigzag pattern. H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 - 23

6. The clothes dryer according to any one of the preceding claims, wherein a lowest end portion of a refrigerant pipe of the first condenser part is arranged on the condensation water line.

7. The clothes dryer according to any one of the preceding claims, wherein a refrigerant pipe of the second condenser part is disposed below the condensation water line.

8. The clothes dryer according to any one of the preceding claims, wherein a refrigerant pipe of the second condenser part is extended from a lowest end portion of a refrigerant pipe of the first condenser part.

9. The clothes dryer according to any one of the preceding claims, wherein the second condenser part comprises a refrigerant line extended from the first condenser part and/or integrally formed with the first condenser part.

10. The clothes dryer according to any one of the preceding claims, wherein a refrigerant pipe of the first condenser part and a refrigerant pipe of the second condenser part are formed in the same heat dissipation fins.

11. The clothes dryer according to any one of the preceding claims 1 to 8, wherein the second condenser part comprises an independent refrigerant line separated from the first condenser part.

12. The clothes dryer of claim 11, wherein the second condenser part comprises at least one heat dissipation fin separated from heat dissipation fins of the first condenser part.

13. The clothes dryer of claim 11 or 12, wherein the first condenser part and the second condenser part are connected by a refrigerant circulation line. H: \XP\Interwoven\NRPortbl\DCC\IXP\8510181_1.docx-19/10/2015 - 24

14. The clothes dryer according to any one of the preceding claims, further comprising a heater for heating air to be supplied to the drum.

15. The clothes dryer of claim 14, wherein the heater is provided in an intake duct for supplying air into the drum.

16. A clothes dryer having a rotatable drum for drying clothes placed therein, a drying duct arranged in an air flow path including the drum for circulation of drying air around the air flow path and through the drum, a heat pump arranged for dehumidifying air from the drum and flowing on said air flow path, the heat pump having a first condenser configured to liquefy refrigerant circulated from a compressor of the heat pump, and a second condenser configured to condense again the refrigerant condensed from the first condenser, the second condenser being positioned to be cooled by condensation water recovered from said air by an evaporator of said heat pump pursuant to said dehumidification.

17. The clothes dryer of claim 16, wherein said second condenser is positioned at a lower portion of the drying duct at a lower portion of the first condenser, said lower portion of the drying duct being arranged for accumulation of said condensation water, and the second condenser is located below a level to which the accumulated condensation water rises in use of the clothes dryer.