EP2796614A1

EP2796614A1 - Clothes dryer and method of cleaning evaporator in clothes dryer

Info

Publication number: EP2796614A1
Application number: EP12859090.8A
Authority: EP
Inventors: Mitsuyuki Furubayashi; Masahiro Kawai; Mikio Tahara; Norihiko Fujiwara
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2011-12-20
Filing date: 2012-12-10
Publication date: 2014-10-29
Also published as: EP2796614A4; CN104011285A; JPWO2013094145A1; WO2013094145A1

Abstract

Clothes dryer (1) of the present invention includes drying chamber (9), air passage (10), heat pump device (7) provided in air passage (10) and including condenser (3) and evaporator (5) connecting with pipe (6) to circulate a refrigerant, air blower (8) for blowing air into air passage (10), discharging unit (15) for discharging water to evaporator (5), water storage tank (13) for storing therein dehumidified water generated on evaporator (5), and controller (20). Controller (20) discharges the water from discharging unit (15) to discharge the dehumidified water stored in water storage tank (13) to evaporator (5). With this, the water which removes lint and contains a scale component adherent onto evaporator (5) is washed away with the dehumidified water stored in water storage tank (13).

Description

TECHNICAL FIELD

The present invention relates to a clothes dryer drying an article to be dried, such as clothes, and a method of cleaning an evaporator in the clothes dryer.

BACKGROUND ART

In a conventional clothes dryer which mounts a heat pump device thereon, lint caused from a fiber product, such as clothes, is mixed into drying air. The mixed lint adheres and accumulates onto an air blower and a heat exchanger provided in a circulation air passage. As a result, the lint lowers a function of the air blower and the heat exchanger. Therefore, the conventional clothes dryer has, in the circulation air passage, a lint filter collecting the lint mixed into the drying air.
However, since the drying air flowing in the circulation air passage is required to ensure a fixed amount of air blown, a mesh of the lint filter cannot be made finer. Consequently, it is difficult for the lint filter to completely remove the lint from the drying air passing therethrough. As a result, the lint which passes through the lint filter adheres onto the heat exchanger to lower the function of the heat exchanger. Therefore, the conventional clothes dryer having a washing function washes away the lint adherent onto the heat exchanger with tap water (for instance, see Patent Literature 1).
Hereinafter, a configuration of the conventional clothes dryer described in Patent Literature 1 will be described with reference to FIG. 8.
FIG. 8 is a block diagram of the conventional clothes dryer having a washing function.
As shown in FIG. 8, the conventional clothes dryer having a washing function includes at least drum 52, outer tub 53, circulation air passage 60, and heat pump device 59. Drum 52 is rotatably provided in outer tub 53, and accommodates therein an article to be dried, such as clothes 51, to be rotatably driven. The clothes dryer supplies water into outer tub 53 via water supply valve 64, drains the water from the outer tub 53, and controls rotation of drum 52 to execute washing, rinsing, spin-drying, and drying steps.
To circulate a refrigerant, heat pump device 59 includes compressor 54, condenser 55, expansion device 56, and evaporator 57 connected with pipe 58. Condenser 55 and evaporator 57 in heat pump device 59 are disposed in circulation air passage 60 through which drying air is circulated.
Exhaust port 61 is provided in an upper front of outer tub 53. Air blow port 62 is provided in an upper portion of a rear surface of outer tub 53. Circulation air passage 60 connects exhaust port 61 and air blow port 62. Circulation air passage 60 has an inlet which flows the drying air thereinto and communicates with exhaust port 61, and an outlet which communicates with air blow port 62.
Air blower 63 is provided in circulation air passage 60 between condenser 55 in heat pump device 59 and air blow port 62, and blows the drying air.
A drying operation of the conventional clothes dryer having a washing function will be described below.
The drying operation is started to operate compressor 54 in heat pump device 59 and air blower 63 that blows the drying air into circulation air passage 60. The drying air is blown from air blow port 62 in circulation air passage 60 into drum 52. The drying air which is blown into drum 52 comes into contact with clothes 51 therein, and then takes the water from clothes 51 for drying.
Thereafter, the drying air which takes the water from clothes 51 to have high humidity flows from exhaust port 61 into circulation air passage 60. The high-humidity drying air is cooled by evaporator 57 in heat pump device 59 to be deprived of latent heat, and is then condensed to be dehumidified. The dehumidified drying air has lowered absolute humidity to be dried. The drying air is heated again by condenser 55 in heat pump device 59 to become dry hot air which is then blown from air blow port 62 into drum 52.
That is, the drying air blown from air blower 63 is circulated through circulation air passage 60 into drum 52 to execute the drying operation for clothes 51.
In the drying step, lint separated from clothes 51 in drum 52 is mixed into the drying air circulated in circulation air passage 60. The mixed lint adheres onto evaporator 57 to cause clogging between fins (not shown) of evaporator 57. As a result, the amount of the drying air flowing in circulation air passage 60 is reduced to lower heat exchange efficiency of heat pump device 59.
As shown in FIG. 8, the conventional clothes dryer having a washing function has cleaning unit 65 that opens openable and closable water supply valve 64 to inject a water solution for cleaning a heat exchanger to evaporator 57 and condenser 55 as the heat exchanger. Cleaning unit 65 injects the water solution for cleaning the heat exchanger to remove the lint adherent onto evaporator 57 and condenser 55.
As the water solution for cleaning the heat exchanger, tap water is used. In addition, the lint is removed with the condensed water generated on evaporator 57.
However, the conventional clothes dryer having a washing function removes the lint with the tap water injected from cleaning unit 65 to clean the heat exchanger. Therefore, when the tap water adherent onto the heat exchanger is evaporated, a scale component included therein remains as an evaporation residue on a surface of the heat exchanger. As a result, heat exchange efficiency of evaporator 57 and condenser 55 configuring the heat exchanger is lowered. The scale or scale component means a calcium or magnesium component contained in the water, such as the tap water, which is precipitated and deposited as an oxide, sulfide, carbonate, and carbohydrate. Ditto with the below.
In addition, when dried, the lint adherent onto evaporator 57 is fixed onto a surface of evaporator 57. Consequently, it is difficult to remove the lint fixed with the condensed water generated on the evaporator.

Citation List

Patent Literature

PTL 1: Unexamined Japanese Patent Publication No. 2005-224491

SUMMARY OF THE INVENTION

To solve the above problems, a clothes dryer of the present invention includes a drying chamber for accommodating therein an article to be dried, an air passage through which drying air discharged from the drying chamber is circulated into the drying chamber again, a heat pump device provided in the air passage and includes a compressor, a condenser, an expansion device, and an evaporator connected with a pipe to circulate a refrigerant, an air blower for blowing the air into the air passage, a discharging unit for discharging water to the evaporator, a water storage tank for storing therein dehumidified water generated on the evaporator, and a controller for controlling a drying operation. The controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank to the evaporator.
With this, the water which contains the scale component adherent onto the evaporator can be washed away with the dehumidified water stored in the water storage tank. Therefore, the scale component contained in the water can be prevented from adhering onto the evaporator. As a result, heat exchange efficiency of the evaporator and the condenser configuring a heat exchanger in the heat pump device can be prevented from being lowered. The clothes dryer can thus stably maintain drying performance for a long period.
A method of cleaning an evaporator in a clothes dryer of the present invention includes a first step of supplying water to the evaporator in a heat pump device to remove lint adherent onto the evaporator, and a second step of removing the water adherent onto the evaporator with dehumidified water stored in a water storage tank after execution of the first step.
With this, the water which is adherent onto the evaporator can be washed away with the dehumidified water stored in the water storage tank. Therefore, the scale component contained in the water can be prevented from adhering onto the evaporator. As a result, heat exchange efficiency of the evaporator can be prevented from being lowered. The evaporator in the clothes dryer can thus be maintained with high performance and reliability for a long period.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a clothes dryer according to a first exemplary embodiment of the present invention.
FIG. 2 is a block diagram of the clothes dryer of the exemplary embodiment.
FIG. 3 is a time chart showing an operation of the clothes dryer of the exemplary embodiment.
FIG. 4 is a flowchart of assistance in explaining an operation of the clothes dryer including a method of cleaning an evaporator in the clothes dryer of the exemplary embodiment.
FIG. 5A is a schematic diagram showing a flow of water continuously discharged from a first discharging unit during lint removal according to the clothes dryer of the exemplary embodiment.
FIG. 5B is a schematic diagram showing a flow of water intermittently discharged from the first discharging unit during lint removal according to the clothes dryer of the exemplary embodiment.
FIG. 6A is a schematic diagram of a clothes dryer according to a second exemplary embodiment of the present invention during lint removal.
FIG. 6B is a schematic diagram of the clothes dryer of the exemplary embodiment during water removal.
FIG. 7 is a schematic diagram of a clothes dryer according to a third exemplary embodiment of the present invention during lint removal.
FIG. 8 is a block diagram of a conventional clothes dryer.

DESCRIPTION OF EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the exemplary embodiments.

(FIRST EXEMPLARY EMBODIMENT)

Hereinafter, a clothes dryer of a first exemplary embodiment of the present invention will be described with reference to FIGS. 1 and 2.
FIG. 1 is a schematic diagram of the clothes dryer according to the first exemplary embodiment of the present invention. FIG. 2 is a block diagram of the clothes dryer of the exemplary embodiment.
As shown in FIGS. 1 and 2, clothes dryer 1 of this exemplary embodiment includes heat pump device 7 having at least evaporator 5, drying chamber 9, air passage 10 through which drying air is circulated in a direction indicated by arrows A, air blower 8, a discharging unit discharging water to evaporator 5, water storage tank 13, and controller 20. Here, the discharging unit includes a first discharging unit discharging the water and a second discharging unit discharging dehumidified water, or switchably supplies and discharges the water or the dehumidified water.
In heat pump device 7, compressor 2, condenser 3, expansion device 4, and evaporator 5 are connected with pipe 6 to circulate a refrigerant therebetween. Compressor 2 compresses the refrigerant. Condenser 3 releases heat of the high-temperature and high-pressure refrigerant compressed by compressor 2. Expansion device 4 includes e.g., a capillary tube and a valve to reduce a pressure of the high-pressure refrigerant. With the low-pressure refrigerant reduced in pressure by expansion device 4, evaporator 5 takes heat from e.g., the high-humidity drying air circulated in air passage 10 to dehumidify the drying air.
Condenser 3 and evaporator 5 in heat pump device 7 include a fin tube heat exchanger having e.g., a plurality of fins 5a. Pipe 6 is formed of e.g., a copper pipe, and flows the refrigerant therethrough. Pipe 6 extends through fins 5a. Fins 5a through which pipe 6 extends are parallel in air passage 10 with predetermined spacing. A channel for the drying air is formed of a gap between fins 5a. Fins 5a are each formed of an aluminum plate having e.g., a thickness of 0.08 mm to 0. 2 mm by e.g., punching. The fin tube heat exchanger is formed by arranging fins 5a through which pipe 6 extends, at a fin pitch of e.g., approximately 1. 2 mm.
As shown in FIG. 1, air passage 10 has therein evaporator 5 cooling and dehumidifying the drying air, condenser 3 heating the dehumidified low-temperature drying air, and air blower 8 sucking, exhausting, and blowing the drying air. Both ends of air passage 10 are annually connected to communicate with drying chamber 9 accommodating clothes 23 therein for circulating the drying air. Filter 11 is detachably attached to air passage 10 between drying chamber 9 and evaporator 5 communicating with each other. Filter 11 collects lint caused from clothes 23 during a drying operation.
Drain port 12 and water storage tank 13 are provided below evaporator 5. Water storage tank 13 stores therein the dehumidified water generated on evaporator 5. Switch valve 14 is switched to water storage tank 13 storing the dehumidified water therein or drain port 12 discharging the water and the dehumidified water to an outside of the clothes dryer. Water storage tank 13 has a volume which can accommodate therein the dehumidified water generated at the time of operating clothes dryer 1 multiple times. However, when the dehumidified water exceeds a predetermined amount to be stored in water storage tank 13, switch valve 14 is switched to drain port 12 to discharge the excessive dehumidified water to the outside of the clothes dryer.
As shown in FIG. 1, first discharging unit (discharging unit) 15 is provided above end face 5b of evaporator 5 at an upstream side of a flow of the drying air. First discharging unit 15 discharges the water, such as tap water, to evaporator 5. Water supply valve 17 provided in water supply path 16 is opened and closed to discharge and stop the water from first discharging unit 15. With this, the lint adherent onto evaporator 5 can be removed. The water is discharged from first discharging unit 15 to end face 5b on an upwind side of evaporator 5, that is, on a side in which the drying air flowing in air passage 10 in the direction indicated by arrows A flows into evaporator 5.
As shown in FIG. 1, second discharging unit 19 is provided above evaporator 5 and on a downstream side of first discharging unit 15. Second discharging unit 19 discharges the dehumidified water stored in water storage tank 13 to evaporator 5. The dehumidified water is pumped up by pump 18 from water storage tank 13 to be discharged from second discharging unit 19 to evaporator 5. With this, the dehumidified water discharged from second discharging unit 19 can clean substantially entire (or entire) evaporator 5. The water from water supply path 16 and the dehumidified water from water storage tank 13 may be switchably supplied to first discharging unit (discharging unit) 15 by e.g., a switch valve (not shown). With this, second discharging unit 19 can be omitted to simplify the configuration.
As shown in FIG. 2, controller 20 controls at least compressor 2 in heat pump device 7, air blower 8, switch valve 14, water supply valve 17, and pump 18 to control the drying operation of clothes dryer 1. As described above, the water from first discharging unit 15 and the dehumidified water from second discharging unit 19 are switchably discharged by switching the operations of water supply valve 17 and pump 18.
An operation of the clothes dryer and a method of cleaning the evaporator in the clothes dryer will be described below with reference to FIGS. 3 and 4.
FIG. 3 is a time chart showing the operation of the clothes dryer of the exemplary embodiment. FIG. 4 is a flowchart of assistance in explaining the clothes dryer including the method of cleaning the evaporator in the clothes dryer of the exemplary embodiment.
As shown in FIGS. 3 and 4, the operation of clothes dryer 1 is started (step S10).
Controller 20 intermittently opens and closes (on - off) water supply valve 17 during e.g., predetermined time 0 to T1 before start of the drying operation. During predetermined time 0 to T1, the water, such as the tap water, is intermittently discharged from first discharging unit (discharging unit) 15 to end face 5b of evaporator 5. With this, a first step of removing the lint fixed onto end face 5b of evaporator 5 with the water from first discharging unit (discharging unit) 15 is executed (step S20).
The wording "before start of the drying operation" specifically means "before operation of compressor 2 in heat pump device 7 and air blower 8".
Predetermined time 0 to T1 is time corresponding to time to remove the lint adherent onto evaporator 5, and is set to e.g., 60 seconds. When the predetermined time is made longer, the drying time becomes longer, which is not convenient for the user. Therefore, the predetermined time is preferably set to approximately 15 seconds to 90 seconds.
Controller 20 operates pump 18 during predetermined time T1 to T2, and sucks the dehumidified water from water storage tank 13 to supply it to second discharging unit 19. Second discharging unit 19 discharges the dehumidified water to entire evaporator 5. When the water is discharged from first discharging unit 15 and when the dehumidified water is discharged from second discharging unit 19, switch valve 14 is switched to drain port 12. The water which removes the lint from evaporator 5 and the dehumidified water which washes away the water adherent onto evaporator 5 are drained from drain port 12 to the outside of the clothes dryer. Therefore, the water and the dehumidified water containing the water can be prevented from being stored in water storage tank 13.
More specifically, a surface of evaporator 5 before start of the drying operation is wet with the water discharged from first discharging unit 15 for removing the lint. The dehumidified water stored in water storage tank 13 is discharged to entire evaporator 5 via second discharging unit 19. The water adherent onto evaporator 5 is discharged together with the dehumidified water from drain port 12 to the outside of the clothes dryer. As a result, the water adherent onto evaporator 5 and containing the scale can be removed with the dehumidified water.
From the above, as shown in FIG. 4, a second step of removing the water adherent onto the evaporator with the dehumidified water is executed (step S30). The typical cleaning of the evaporator in the clothes dryer is completed.
As shown in FIGS. 3 and 4, after elapse of predetermined time T2, controller 20 operates compressor 2 in heat pump device 7 and air blower 8 to start the drying operation for an article to be dried, such as clothes 23, thrown into drying chamber 9 (step S40). The drying air which is blown from air blower 8 to be circulated in air passage 10 passes through condenser 3 to be heated with heat released therefrom, and then becomes hot air to be sent into drying chamber 9. The drying air comes into contact with clothes 23 in drying chamber 9, and then takes the water from clothes 23 for drying. The drying air becomes high-humidity air by the water taken from clothes 23. The high-humidity drying air passes through evaporator 5 to be cooled. The drying air whose water vapor is condensed is dehumidified to form the dehumidified water. Therefore, the dehumidified water is formed to be clean without containing the scale component.
After start of the drying operation, the dehumidified water generated due to condensation on evaporator 5 is moved downward by its own weight along surfaces of fins 5a of evaporator 5. By switching switch valve 14 to water storage tank 13, the dehumidified water flows and is stored in water storage tank 13 provided below evaporator 5. With this, a third step of storing the dehumidified water in the water storage tank is executed (step S50).
The dehumidified water maintained clean is stored in water storage tank 13 since the lint and the water are previously washed away from the surface of evaporator 5 before start of the drying operation.
The drying air which is dehumidified by evaporator 5 to have lowered absolute humidity is heated by condenser 3 again to be blown into drying chamber 9.
The drying operation is executed until the clothes is dried (step S60).
From the above, the evaporator in the clothes dryer is cleaned to execute the drying operation.
During the drying operation for the clothes, in heat pump device 7, when controller 20 operates compressor 2, heat of the high-temperature and high-pressure refrigerant compressed by compressor 2 is released by condenser 3. The heat-released high-pressure refrigerant is reduced in pressure by expansion device 4 to have low pressure and low temperature. The low-pressure and low-temperature refrigerant takes heat from the drying air in evaporator 5 to return into compressor 2 again. That is, a heat amount obtained by adding a heat amount obtained from input power into compressor 2 to a heat amount taken by the low-temperature and low-pressure refrigerant in evaporator 5 is released from condenser 3. Therefore, heat energy released from condenser 3 into the drying air is substantially equal to the sum of the heat amount obtained from the input power into compressor 2 and the heat amount taken from the drying air in evaporator 5.
Condenser 3 can obtain an output (heat energy) above the input power inputted into compressor 2 to heat the drying air which can then be thrown into clothes 23 in drying chamber 9. With this, the drying air dehumidified in evaporator 5 and heated by the condenser is thrown into drying chamber 9, and comes into contact with clothes 23 for drying.
As the drying of clothes 23 proceeds, the lint is caused from clothes 23. The caused lint is mixed into the drying air, is conveyed to filter 11 by the circulated drying air, and is collected by filter 11.
However, to ensure a fixed amount of air blown and to prevent excessive power consumption, typically, a mesh of filter 11 cannot be made finer. Therefore, part of the lint can pass through filter 11 without being collected by filter 11. The lint which passes through filter 11 adheres onto end face 5b of evaporator 5 on the upstream side of the direction in which the drying air flows. In this exemplary embodiment, the fin pitch in evaporator 5 is e.g., approximately 1. 2 mm. Accordingly, the lint which passes through filter 11 adheres only onto end face 5b of evaporator 5.
After completion of the drying operation for the article to be dried, such as clothes 23, the lint adheres onto filter 11 and end face 5b of evaporator 5. In this case, the user can remove the lint adherent onto filter 11 by detaching detachable filter 11. However, the user cannot remove the lint adherent onto evaporator 5.
The amount of the lint adherent onto evaporator 5 is small at an early stage in which the number of drying operations is low. However, as the number of drying operations is increased, a large amount of lint adheres onto evaporator 5. Consequently, air passage pressure loss in evaporator 5 is gradually increased to gradually decrease the amount of the circulated drying air. As a result, drying performance of the clothes dryer is lowered with increase of the number of drying operations.
Therefore, as described with reference to FIGS. 3 and 4, in this exemplary embodiment, controller 20 intermittently opens and closes water supply valve 17 e.g., before start of the drying operation. During the predetermined time (e.g., 60 seconds, and opening time and closing time are substantially the same (or the same)), the water is intermittently discharged from first discharging unit 15 to end face 5b of evaporator 5 onto which the lint is adherent.
The reason why the water is intermittently discharged from first discharging unit 15 will be described below with reference to FIGS. 5A and 5B.
FIG. 5A is a schematic diagram showing a flow of the water continuously discharged from the first discharging unit during lint removal according to the clothes dryer of the exemplary embodiment. FIG. 5B is a schematic diagram showing a flow of the water intermittently discharged from the first discharging unit during lint removal according to the clothes dryer of the exemplary embodiment.
As shown in FIG. 5A, the lint is separated with the water continuously discharged from the first discharging unit, and is then collected to be a lump. In this state, the discharged water can flow so as to avoid the lump of the collected lint. In this case, as indicated by arrows B, the water continuously flows in such a manner as to avoid the lint lump. Consequently, the lint cannot be removed.
As shown in FIG. 5B, the water is intermittently discharged from the first discharging unit to form the lint lump, as indicated by arrows C, and then is repeatedly collided therewith. Repeated collision of the intermittently discharged water with the lint lump can gradually separate the originally adherent lint and the separated-lint lump to remove the lint adherent onto evaporator 5.
Typically, in the case that the amount of the water contained in the clothes and the amount of clothes are large, when the drying operation is started immediately after completion of the washing step, the dehumidified water is generated from evaporator 5 for a short time. However, in the case that the amount of clothes dried and the amount of the water contained in the clothes are small, when the drying operation is started immediately after completion of the washing step, the water removing the lint is dried before the dehumidified water adheres onto evaporator 5. Consequently, the scale contained in the water can adhere onto evaporator 5.
As described with reference to FIG. 4, in this exemplary embodiment, before start of the drying operation, the lint is removed with the water to remove the water adherent onto evaporator 5 with the dehumidified water stored in water storage tank 13. With this, the dehumidified water can be discharged before the water is dried, to flow the water in evaporator 5. The dehumidified water is previously stored in water storage tank 13 before start of the drying operation. Therefore, an amount necessary for removing the water can be ensured. As a result, the water adherent onto evaporator 5 can be certainly removed with the dehumidified water which is previously stored in water storage tank 13.
As described above, in this exemplary embodiment, before start of the drying operation, the water, such as the tap water, is discharged from first discharging unit (discharging unit) 15 to remove the lint adherent onto evaporator 5. In this state, the water containing the scale component is adherent onto evaporator 5. Thereafter, the dehumidified water stored in water storage tank 13 is discharged from second discharging unit 19 to evaporator 5 to remove the water adherent onto evaporator 5. That is, the lint is removed with the water before start of the drying operation, and then, the water adherent onto evaporator 5 can be washed away with the dehumidified water stored in water storage tank 13 before being dried. This can prevent clogging in evaporator 5 due to the lint and adhesion and accumulation of the scale component contained in the water. As a result, heat exchange efficiency of evaporator 5 can be prevented from being lowered to maintain high drying performance.
In this exemplary embodiment, before start of the drying operation, the lint adherent onto evaporator 5 can be removed. Therefore, during drying of the clothes, air passage pressure loss in evaporator 5 can be prevented from being increased. As a result, the drying air flowing in the air passage can be stably circulated in a proper amount of air blown to execute the drying operation.
As shown in FIG. 4, in this exemplary embodiment, before start of the drying operation, the lint is removed and the water is washed away. However, the present invention is not limited to this. For instance, after completion of the drying operation, the water may be discharged from the first discharging unit (discharging unit) to remove the lint, and the dehumidified water stored in the water storage tank may be discharged from the second discharging unit to wash away the water. In this case, the first and second steps shown in FIG. 4 are executed after the third step and after completion of the drying operation. With this, the same effect as the above can be obtained. At the time of start of the drying operation, even when not stored in the water storage tank, the dehumidified water stored during the drying operation can be used to wash away the water adherent onto the evaporator.

(SECOND EXEMPLARY EMBODIMENT)

Hereinafter, a clothes dryer according to a second exemplary embodiment of the present invention will be described with reference to FIGS. 6A and 6B.
FIG. 6A is a schematic diagram of the clothes dryer according to the second exemplary embodiment of the present invention during lint removal. FIG. 6B is a schematic diagram of the clothes dryer of the exemplary embodiment during water removal.
As shown in FIGS. 6A and 6B, in the clothes dryer of this exemplary embodiment, water discharge area 21 discharging the water, such as the tap water, discharged from first discharging unit 15 to evaporator 5 is equal to or smaller than dehumidified water discharge area 22 discharging the dehumidified water discharged from second discharging unit 19 to evaporator 5. Other configurations are the same as the first exemplary embodiment. The same configurations are indicated by similar reference numerals, and the first exemplary embodiment is cited for the detailed description.
That is, first discharging unit 15 removing the lint adherent onto evaporator 5 discharges the water to near end face 5b of evaporator 5. Second discharging unit 19 removing the water adherent onto evaporator 5 discharges the dehumidified water to entire evaporator 5.
Specifically, water discharge area 21 shown in FIG. 6A and discharging the water from first discharging unit 15 to evaporator 5 is equal to or smaller than dehumidified water discharge area 22 shown in FIG. 6B and discharging the dehumidified water from second discharging unit 19 to remove the water.
That is, water discharge area 21 is within dehumidified water discharge area 22. The water is thus concentratively discharged to near end face 5b of evaporator 5 onto which a large amount of lint adheres. With this, the lint adherent onto evaporator 5 can be removed more certainly.
The dehumidified water is discharged to dehumidified water discharge area 22 larger than water discharge area 21. The water adherent onto evaporator 5 can thus be removed with the dehumidified water more certainly. As a result, the scale caused by evaporation of the water which removes the lint to remain can be certainly prevented from adhering onto evaporator 5.
In this exemplary embodiment, dehumidified water discharge area 22 discharging the dehumidified water is entire evaporator 5. However, the present invention is not limited to this. For instance, entire evaporator 5 is not required to be dehumidified water discharge area 22. That is, when water discharge area 21 of the water adherent onto evaporator 5 can be limited, dehumidified water discharge area 22 may be to discharge the dehumidified water to at least water discharge area 21.

(THIRD EXEMPLARY EMBODIMENT)

Hereinafter, a clothes dryer according to a third exemplary embodiment of the present invention will be described with reference to FIG. 7.
FIG. 7 is a schematic diagram of the clothes dryer according to the third exemplary embodiment of the present invention during lint removal.
As shown in FIG. 7, in the clothes dryer of this exemplary embodiment, first discharging unit 15 is provided above a downstream side of end face 5b on the upstream side of evaporator 5 into which the drying air flows, and discharges the water to end face 5b on the upstream side of evaporator 5. Other configurations are the same as the first exemplary embodiment. The same configurations are indicated by similar reference numerals, and the first exemplary embodiment is cited for the detailed description.
That is, as shown in FIG. 7, first discharging unit 15 is provided above the downstream side of evaporator 5 in the direction in which the drying air flows. First discharging unit 15 discharges the water to the lint adherent onto end face 5b of evaporator 5.
In this case, a direction of the water discharged from first discharging unit 15 is opposite to the direction in which the drying air flows. With this, the water can be discharged from the substantially opposite direction of a direction in which the lint adheres (or from an interior of evaporator 5). As a result, the water can be discharged from the interior of the evaporator to effectively pullably separate the lint adherent onto the end face of the evaporator to outside.
In addition, the lint can be pullably separated so as to be pushed out with the water to the upstream side of evaporator 5. The lint can be separated more easily than when the water is vertically discharged to pullably separate the lint. With this, the lint lump is unlikely to be caused. As a result, the lint can be easily removed even when a pressure of the water is low.
In each of the exemplary embodiments, as the water removing the lint adherent onto evaporator 5, the tap water is used. However, the present invention is not limited to this. For instance, the water may be filtered bath water and well water, and water which washes away the lint and is dried on the surface of evaporator 5 to leave the scale. In this case, the same effect as the exemplary embodiments can be obtained.
In each of the exemplary embodiments, to remove the water, such as the tap water, with the dehumidified water, second discharging unit 19 is provided to discharge the dehumidified water to evaporator 5. However, the present invention is not limited to this. For instance, first discharging unit 15 may be discharging unit 15 which selectively discharges the water and the dehumidified water. With this, the configuration of the discharging unit can be simplified.
In each of the exemplary embodiments, the pressure of the water, such as the tap water, supplied from outside through water supply path 16 discharges the water from the first discharging unit to remove the lint. However, the present invention is not limited to this. For instance, a discharging pump may be provided ahead of first discharging unit 15 to pressurize and discharge the water. With this, even in a place in which the pressure of the water, such as the tap water, is low, sufficient lint removal performance can be ensured. Further, when there is no water supply equipment outside, a water supply tank and a discharging pump are provided, the water supply tank storing therein the water, such as the tap water, and the discharging pump discharging the water in the water supply tank. The water supply tank and the discharging pump may be combined together with the water supply passage and the water supply valve of the exemplary embodiments to configure the clothes dryer. With this, a selection area of a place for use can be widened to enhance general-purpose properties.
In each of the exemplary embodiments, the water is intermittently discharged from the first discharging unit. However, the present invention is not limited to this. For instance, high-pressure water may be continuously discharged.
In each of the exemplary embodiments, the on and off periods during intermittent discharge of the water are the same. However, the present invention is not limited to this. The on and off periods may be optional.
In each of the exemplary embodiments, the fin pitch in evaporator 5 is approximately 1.2 mm. However, the present invention is not limited to this. For instance, the fin pitch may be made narrower to configure evaporator 5. With this, the lint can adhere onto end face 5b of evaporator 5 more certainly. As a result, the lint can be easily removed. However, when the fin pitch is made narrower, air passage pressure loss in the drying air which passes through the channel of the evaporator is increased. Therefore, the fin pitch is preferably set to a value in which a balance between lint removal and air passage pressure loss is optimum.
In each of the exemplary embodiments, the present invention has been described by taking the clothes dryer as an example. However, the present invention is not limited to this. For instance, the present invention may be a washer dryer having a washing function and performing washing and drying. The same effect can be obtained.
Needless to say, part of each of the exemplary embodiments may be combined with another exemplary embodiment.
As described above, the clothes dryer of the present invention includes the drying chamber for accommodating therein the article to be dried, the air passage through which the drying air discharged from the drying chamber is circulated into the drying chamber again, the heat pump device provided in the air passage and includes the compressor, the condenser, the expansion device, and the evaporator connected with the pipe to circulate the refrigerant, the air blower for blowing the air into the air passage, the discharging unit for discharging the water to the evaporator, the water storage tank for storing therein the dehumidified water generated on the evaporator, and the controller for controlling a drying operation. The controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank to the evaporator. With this, the water which removes the lint and contains the scale component adherent onto the evaporator can be washed away with the dehumidified water stored in the water storage tank. Therefore, the scale component contained in the water which removes the lint can be prevented from adhering onto the evaporator. As a result, heat exchange efficiency of the evaporator configuring the heat exchanger in the heat pump device can be prevented from being lowered. The clothes dryer can thus stably maintain drying performance for a long period.
According to the clothes dryer of the present invention, before start of the drying operation, the controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank. With this, before start of the drying operation, the lint can be previously removed with the water to wash away the water containing the scale component adherent onto the evaporator with the dehumidified water stored in the water storage tank.
According to the clothes dryer of the present invention, after completion of the drying operation, the controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank. With this, the dehumidified water stored in the water storage tank during the drying operation can effectively wash away the water containing the scale component adherent onto the evaporator.
According to the clothes dryer of the present invention, the controller intermittently discharges the water from the discharging unit. With this, when the lint separated with the discharged water is collected to be a lump, the water is repeatedly intermittently collided with the lint lump so that the lint can be separated more certainly. As a result, the lint adherent onto the evaporator can be removed more efficiently.
According to the clothes dryer of the present invention, the water discharge area of the discharging unit for discharging the water to the evaporator is equal to or smaller than the dehumidified water discharge area for removing the water with the dehumidified water. With this, the water can be concentratively discharged to a portion of the evaporator onto which a large amount of lint adheres. The lint adherent onto the evaporator can thus be removed more efficiently. Further, the water adherent onto the wide area of the evaporator can be removed with the dehumidified water more certainly. As a result, the scale caused in the water which remains on the surface of the evaporator to be evaporated can be prevented from adhering onto the evaporator.
According to the clothes dryer of the present invention, the discharging unit is provided near the end face on the upstream side of the evaporator into which the drying air flows. With this, the water can be concentratively discharged to near the end face of the evaporator onto which a large amount of lint is likely to adhere.
According to the clothes dryer of the present invention, the discharging unit is provided at the downstream side of the end face on the upstream side of the evaporator into which the drying air flows, and the discharging unit discharges the water to the end face on the upstream side of the evaporator. With this, the water can be discharged onto the end face of the evaporator from the direction opposite to the side in which the lint flows to adhere. As a result, the water is discharged from the interior of the evaporator to effectively pullably separate the lint adherent onto the end face of the evaporator to the outside.
The clothes dryer of the present invention further includes the second discharging unit for discharging the dehumidified water in the water storage tank to the evaporator. With this, the scale component contained in the water can be prevented from being mixed and accumulated into the discharge path for the dehumidified water. As a result, the water which contains the scale component and remains on the surface of the evaporator can be removed with the clean dehumidified water more certainly.
According to the clothes dryer of the present invention, the water is any one of the tap water, bath water, and well water. With this, the clothes dryer can be excellent in general-purpose properties.
The method of cleaning the evaporator in the clothes dryer of the present invention includes the first step of supplying the water to the evaporator in the heat pump device to remove lint adherent onto the evaporator, and the second step of removing the water adherent onto the evaporator with the dehumidified water stored in the water storage tank after execution of the first step. With this, the water which removes the lint and is adherent onto the evaporator can be washed away with the dehumidified water stored in the water storage tank. Therefore, the scale component contained in the water can be prevented from adhering onto the evaporator, to remove the lint. As a result, heat exchange efficiency of the evaporator can be prevented from being lowered. The evaporator in the clothes dryer can thus be maintained with high performance and reliability for a long period.
The method of cleaning the evaporator in the clothes dryer of the present invention further includes the third step of storing the dehumidified water generated on the evaporator into the water storage tank. The first and second steps are executed before start of the drying operation. The third step is executed after the start of the drying operation. With this, before start of the drying operation, the water which removes the lint and is adherent onto the evaporator can be washed away with the dehumidified water stored in the water storage tank. As a result, the scale component contained in the water can be prevented from adhering onto the evaporator, to remove the lint.
The method of cleaning the evaporator in the clothes dryer of the present invention further includes the third step of storing the dehumidified water generated on the evaporator into the water storage tank. The third step is executed after start of the drying operation. The first and second steps are executed after completion of the drying operation. With this, after start of the drying operation, the dehumidified water dehumidified by the evaporator can be stored in the water storage tank, and after completion of the drying operation, the water removes the lint and can be washed away with the dehumidified water which is previously stored in the water storage tank. Therefore, even when the dehumidified water is not stored in the water storage tank at the time of start of the drying operation, the dehumidified water stored during the drying operation can certainly wash away the water adherent onto the evaporator.
According to the method of cleaning the evaporator in the clothes dryer of the present invention, the water is any one of the tap water, bath water, and well water. With this, the clothes dryer can be excellent in general-purpose properties.

INDUSTRIAL APPLICABILITY

The present invention is useful for the field of the clothes dryer in which the scale adheres onto the evaporator so that heat exchange efficiency is likely to be lowered.

REFERENCE MARKS IN THE DRAWINGS

1: clothes dryer
2, 54: compressor
3, 55: condenser
4, 56: expansion device
5, 57: evaporator
5a: fin
5b: end face
6, 58: pipe
7: heat pump device
8, 63: air blower
9: drying chamber
10: air passage
11: filter
12: drain port
13: water storage tank
14: switch valve
15: first discharging unit (discharging unit)
16: water supply path
17, 64: water supply valve
18: pump
19: second discharging unit
20: controller
21: water discharge area
22: dehumidified water discharge area
23, 51: clothes
52: drum
53: outer tub
59: heat pump device
60: circulation air passage
61: exhaust port
62: air blow port
65: cleaning unit

Claims

A clothes dryer comprising:
a drying chamber for accommodating therein an article to be dried;

an air passage through which drying air discharged from the drying chamber is circulated into the drying chamber again;

a heat pump device provided in the air passage and including a compressor, a condenser, an expansion device, and an evaporator connected with a pipe to circulate a refrigerant;

an air blower for blowing air into the air passage;

a discharging unit for discharging water to the evaporator;

a water storage tank for storing therein dehumidified water generated on the evaporator; and

a controller for controlling a drying operation,

wherein the controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank to the evaporator.
The clothes dryer according to claim 1, wherein before start of the drying operation, the controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank to the evaporator.
The clothes dryer according to claim 1, wherein after completion of the drying operation, the controller discharges the water from the discharging unit, and then discharges the dehumidified water stored in the water storage tank to the evaporator.
The clothes dryer according to claim 1, wherein the controller intermittently discharges the water from the discharging unit.
The clothes dryer according to claim 1, wherein a water discharge area of the discharging unit for discharging the water to the evaporator is equal to or smaller than a dehumidified water discharge area for removing the water with the dehumidified water.
The clothes dryer according to claim 1, wherein the discharging unit is provided near an end face on an upstream side of the evaporator into which the drying air flows.
The clothes dryer according to claim 1,
wherein the discharging unit is provided at a downstream side of an end face on an upstream side of the evaporator into which the drying air flows,
wherein the discharging unit discharges the water to the end face on the upstream side of the evaporator.
The clothes dryer according to claim 1, further comprising a second discharging unit for discharging the dehumidified water in the water storage tank to the evaporator.
The clothes dryer according to claim 1, wherein the water is any one of tap water, bath water, and well water.
A method of cleaning an evaporator in a clothes dryer comprising:
a first step of supplying water to the evaporator in a heat pump device to remove lint adherent onto the evaporator; and

a second step of removing the water adherent onto the evaporator with dehumidified water stored in a water storage tank after execution of the first step.
The method of cleaning an evaporator in a clothes dryer according to claim 10, further comprising a third step of storing the dehumidified water generated on the evaporator into the water storage tank,
wherein the first and second steps are executed before start of a drying operation, and
wherein the third step is executed after the start of the drying operation.
The method of cleaning an evaporator in a clothes dryer according to claim 10, further comprising a third step of storing the dehumidified water generated on the evaporator into the water storage tank,
wherein the third step is executed after start of the drying operation, and
wherein the first and second steps are executed after completion of the drying operation.
The method of cleaning an evaporator in a clothes dryer according to claim 10, wherein the water is any one of tap water, bath water, and well water.