EP3184934B1

EP3184934B1 - Heat pump system, combo washer-dryer, and dryer

Info

Publication number: EP3184934B1
Application number: EP14900320.4A
Authority: EP
Inventors: Peishi Lv; Sheng Xu; Huacheng SONG; Shiqiang SHAN
Original assignee: Qingdao Haier Washing Machine Co Ltd
Current assignee: Qingdao Haier Washing Machine Co Ltd
Priority date: 2014-08-18
Filing date: 2014-11-17
Publication date: 2019-06-19
Anticipated expiration: 2034-11-17
Also published as: JP2017526887A; US20180016726A1; KR20170044673A; JP6389563B2; CN105466078A; EP3184934A4; WO2016026226A1; EP3184934A1

Description

TECHNICAL FIELD

The present disclosure relates to the field of heating and dehumidifying of heat pumps, and in particular to a heat pump system, a washing-drying integrated machine and a clothes dryer.

BACKGROUND

Clothes dryers in the existing art include a direct-drainage type clothes dryer and a condensation type clothes dryer; both the direct-drainage type clothes dryer and the condensation type clothes dryer are prepared in a way that an air inflow passage and an air outflow passage are communicated with a drum in a tank body; a difference between the direct-drainage type clothes dryer and the condensation type clothes dryer is that a heater for heating air flowing into a washing drum is mounted in the air inflow passage of the direct-drainage type clothes dryer; the air inflow passage and the air outflow passage of the condensation type clothes dryer are communicated to form an air duct; not only a heating device for heating the air flowing into the washing drum and a fan for feeding the air heated by the heating device into the drum are mounted in the air duct, but also a condensing device for cooling a high-temperature gas flowing out of the washing drum is mounted; and similarly, drying systems of existing washing-drying integrated machines are same as those of the clothes dryers.
In the existing art, many direct-drainage type clothes dryers or washing-drying integrated machines adopt a heat pump drying mode in a drying process; heat pump systems in the washing-drying integrated machines or clothes dryers adopting the heat pump drying mode are used for dehumidifying and heating the air flowing through the air duct; the heat pump system includes an evaporator, a compressor, a condenser and a throttling device; the evaporator, the compressor, the condenser and the throttling device are sequentially communicated through a pipeline to form a refrigerant circulating loop; the evaporator of the heat pump system is arranged at an air inlet of the air duct; the evaporator evaporates a liquid refrigerant into a gaseous refrigerant when refrigerant in the heat pump system enters the evaporator; in this process, the evaporator absorbs surrounding heat, as a condensing device in the air duct used for condensing the air flowing through the air duct; the condenser of the heat pump system is located in the air duct between a fan and the evaporator; the condenser changes a high-temperature and high-pressure gaseous refrigerant into a low-temperature and high-pressure gaseous refrigerant when the refrigerant in the heat pump system enters the condenser; and at the moment, the condenser releases heat to the outside, as a heating device in the air duct used for heating the air flowing through the air duct.
However, for a drum type washing-drying integrated machine or clothes dryer adopting the heat pump drying mode in the existing art, since the temperature of water for rinsing clothes is only slightly higher than 0 DEG C in a low-temperature environment such as 0 DEG C environment, the temperature of the air blowing out from a washing/drying drum is close to 0 DEG C at a stage of starting to dry; in this case, a saturation temperature under a refrigerant saturation pressure in the evaporator of the heat pump system is much lower than 0 DEG C, a load of a compressor system is low, and an input power is small; but the heat for drying the air comes from power input of the compressor system, so the rise of the temperature in the washing/drying drum is extremely slow, which is adverse to the efficiency of drying clothes; and when a evaporation temperature is kept below 0 DEG C for a long time in the low-temperature environment, the evaporator is in contact with moist air blown out of the drum, a large number of frost may be condensed on surfaces of fins of the evaporator, an effective area of the evaporator is reduced, and the circulation of the air in a circulating air duct may be blocked, causing that the refrigerant in the compressor system cannot be completely vaporized, and a liquid-state refrigerant enters the compressor along an air suction pipe of the compressor, leading to a failure of the compressor.
Existing solutions are that (1) an auxiliary heating pipe (wire) is added behind the condenser, and the air heated by the condenser continues to be reheated by the heating pipe (wire), to obtain a higher drying temperature in the low-temperature environment, but an energy consumption level may be increased; (2) a frequency conversion compressor is adopted to operate at a higher operation frequency at a low temperature or when the drying needs to be accelerated, but costs are increased greatly; (3) a high-capacity compressor is adopted, but energy consumption of the high-capacity compressor may be higher at room temperature; and (4) a multi-exhaust-chamber compressor is adopted, but this solution may also increase operation costs.
In view of the above descriptions, there is an urgent need for a new heat pump system to solve problems that a drying efficiency of clothes is low and the compressor is easy to have a failure in the existing art.
JP2004205116A disclose a high performance cold/hot water generator capable of supplying hot water at a high temperature. The cold/hot water generator is provided with a refrigerant amount control mechanism provided at the outlet of a water heat exchanger provided in a heat pump refrigerating cycle. The refrigerant amount control mechanism controls the amount of a cooling medium to be circulated in the refrigerating cycle depending on a boiling temperature target value.
EP2527522A1 discloses a laundry dryer with heat pump system, wherein the heat pump system comprises a closed refrigerant circuit for a refrigerant, the refrigerant circuit includes at least one compressor (10), at least one gas cooler (12), at least one expansion means (14) and at least one evaporator/gas heater (16),the refrigerant circuit is thermally coupled to a drying air circuit of the laundry dryer by the gas cooler (12) and the evaporator/gas heater (16),the gas cooler (12) is a heat exchanger and provided for heating up the drying air stream and cooling down the refrigerant, and the evaporator/gas heater (16) is a heat exchanger and provided for dehumidifying the drying air and heating up the refrigerant, the refrigerant circuit comprises a low pressure side between the outlet of the expansion means (14) and the inlet of the compressor (10), the refrigerant circuit comprises a high pressure side between the outlet of the compressor (10) and the inlet of the inlet of expansion means (14), wherein the refrigerant operates at supercritical conditions in the low pressure side of the refrigerant circuit after a transient sub-critical phase, wherein the laundry dryer comprises at least one refrigerant trap (18) fluidly connected or connectable to at least one part of the refrigerant circuit and valve means (20, 22, 24, 26) to selectively connect and/or disconnect the refrigerant trap (18) to said least one part of the refrigerant circuit.

SUMMARY

In view of this, an objective of the present disclosure is to provide a heat pump system which can increase a load rise rate of a compressor in a low-temperature environment.
A further objective of the present disclosure is to provide a washing-drying integrated machine in which the above heat pump system is arranged to increase the drying efficiency of clothes.
Another objective of the present disclosure is to provide a clothes dryer in which the above heat pump system is arranged to increase the drying efficiency of the clothes. The present disclosure provides a heat pump system for drying clothes according to independent claim 1, a washing-drying integrated machine according to claim 6, and a clothes dryer according to claim 7. Further improvements and embodiments are provided in the dependent claims.
Embodiments of the present disclosure adopt the following technical solutions:

A heat pump system includes an evaporator, a compressor, a condenser and a refrigerant regulating subsystem; where the evaporator, the compressor, the condenser and the refrigerant regulating subsystem are sequentially communicated through a pipeline to form a refrigerant circulating loop; and the refrigerant regulating subsystem includes a first branch and a second branch connected in parallel between the evaporator and the condenser;
the first branch includes a first throttling device having an outlet connected with a pipe inlet of the evaporator, and a liquid storing device located between the first throttling device and the condenser; and
a second throttling device is connected with the second branch in series.

The second branch and the first branch may be connected with a pipe outlet of the condenser through a reversing valve.
Electromagnetic valves are respectively arranged on the first branch between the condenser and the liquid storing device and the second branch between the second throttling device and the condenser.
The first throttling device may be a first capillary tube; the second throttling device may be a second capillary tube; and the length of the first capillary tube may be smaller than that of the second capillary tube.
The first throttling device and the second throttling device may be a same electronic expansion valve; and an opening degree of the electronic expansion valve may be adjustable.
Both the first throttling device and the second throttling device may be electronic expansion valves; and opening degrees of all the electronic expansion valves may be adjustable.
Check valves are respectively arranged on the first branch between the liquid storing device and the first throttling device and the second branch between the second throttling device and the electromagnetic valve.
Also provided is a washing-drying integrated machine including an outer drum, an air duct and an inner drum arranged in the outer drum; an air inlet and an air outlet of the air duct are respectively connected with a rear part and a front part of the outer drum; the air duct and the outer drum form a closed loop; a fan is arranged in the air duct; the washing-drying integrated machine further includes the heat pump system according to any of the above; the evaporator of the heat pump system is arranged at the air inlet of the air duct, for condensing air flowing through the air duct; and the condenser of the heat pump system is located in the air duct between the fan and the evaporator, for heating air flowing through the air duct.
Also provided is a clothes dryer including a tank body, an air duct and a drying drum mounted in the tank body; an air inlet and an air outlet of the air duct are respectively connected with a rear part and a front part of the drying drum to form a closed loop together with the drying drum; a fan is arranged in the air duct; the clothes dryer further includes the heat pump system according to any of the above; the evaporator of the heat pump system is arranged at the air inlet of the air duct, for condensing air flowing through the air duct; and the condenser of the heat pump system is located in the air duct between the fan and the evaporator, for heating air flowing through the air duct.
An auxiliary electric heating device may be arranged in the air duct between the fan and the air outlet of the air duct.
The technical solutions proposed by embodiments of the present disclosure have beneficial technical effects that

(1) the refrigerant regulating subsystem of the heat pump system includes the first branch and the second branch connected between the evaporator and the condenser in parallel; the first branch includes the first throttling device having the outlet connected with the pipe inlet of the evaporator, and the liquid storing device located between the first throttling device and the condenser; the second throttling device is connected with the second branch in series; a flow direction of the refrigerant is the compressor, the condenser, the first branch (the liquid storing device and the first throttling device), the evaporator and the compressor when an environment temperature is high; the flow direction of the refrigerant is the compressor, the condenser, the second branch (the second throttling device), the evaporator and the compressor when an environment temperature is low; therefore, when the temperature is high, the liquid storing device enables a space for accommodating the refrigerant to increase, and pressure load does not increase rapidly; while at a low temperature, the refrigerant enters the evaporator only through the second throttling device from the condenser, since the space for accommodating the refrigerant is reduced, a compressor load may rise rapidly, thereby increasing a load rise rate of the compressor in the low-temperature environment.
(2) the length of the first capillary tube is smaller than that of the second capillary tube, i.e., the length of the second capillary tube is longer, and the capillary tube is set to be longer at the low temperature in order to match a superheat degree of the evaporator in this environment, avoid incomplete evaporation since a pressure rises rapidly and excessive refrigerant enters the evaporator, and avoid a problem of a failure of the compressor since a liquid-state refrigerant enters the compressor along an air suction pipe of the compressor.

BRIEF DESCRIPTION OF DRAWINGS

In order to more clearly illustrate the technical solutions in embodiments of the present disclosure, drawings which are required to be used in the description of embodiments of the present disclosure are briefly described hereinafter. It is apparent that the drawings described below are only some embodiments of the present disclosure; and for those ordinary skilled in the art, other drawings can also be obtained in accordance with contents and these drawings of embodiments of the present disclosure without paying creative efforts.

Fig. 1 is a schematic structural diagram illustrating a heat pump system provided by device embodiments according to the present disclosure; and
Fig. 2 is a schematic structural diagram illustrating a clothes dryer provided by device embodiments according to the present disclosure.

In the figures:

1: Refrigerant regulating subsystem; 2: Condenser; 3: Evaporator; 4: Compressor; 5: Air duct; 6: Tank body; 7: Drying drum;
11: First branch; 12: Second branch;
111: First throttling device; 112: First check valve; 114: Liquid storing device; 116: First electromagnetic valve;
121: Second throttling device; 122: Second electromagnetic valve;
51: Air inlet; 52: Air outlet; 53: Auxiliary electric heating device; 54: Fan; 55: Filter.

DETAILED DESCRIPTION

In order to make solved technical problems, adopted technical solutions and achieved technical effects of the present disclosure clearer, the technical solutions of embodiments of the present disclosure are further described in detail in combination with the drawings below. Apparently, the described embodiments are merely some embodiments of the present disclosure, rather than all embodiments. All other embodiments obtained by those skilled in the art without paying creative efforts fall within a protection scope of the present disclosure, based on embodiments of the present disclosure.
The solution solves a problem of a compressor load at a low temperature in existing art from a new perspective. Fig. 1 is a schematic structural diagram illustrating a heat pump system provided by device embodiments according to the present disclosure. As shown in Fig. 1, the heat pump system includes an evaporator 3, a compressor 4, a condenser 2 and a refrigerant regulating subsystem 1; and the evaporator 3, the compressor 4, the condenser 2 and the refrigerant regulating subsystem 1 are sequentially communicated through a pipeline to form a refrigerant circulating loop, where the refrigerant regulating subsystem 1 includes a first branch 11 and a second branch 12 connected in parallel between the evaporator 3 and the condenser 2.
The first branch 11 includes a first throttling device 111 having an outlet connected with a pipe inlet of the evaporator 3, and a liquid storing device 114 for storing refrigerant; and the liquid storing device 114 is located between the first throttling device 111 and the condenser2.
A second throttling device 121 is connected with the second branch 12 in series.
In the present embodiment, as a solution, the second branch 12 and the first branch 11 are connected with the pipe outlet of the condenser 2 through a reversing valve. The reversing valve is connected with a controller; the reversing valve controls a flow direction of refrigerant flowing out of the condenser 2 according to a received signal sent by the controller and controls the refrigerant to flow through the first branch 11 or the second branch 12; and therefore, the purpose of adopting the reversing valve is to control refrigerant to switch between two flow directions.
Definitely, the present disclosure is not limited to the above solution; as another solution, a first electromagnetic valve 116 can also be arranged on the first branch 11 between the condenser 2 and the liquid storing device 114, and a second electromagnetic valve 122 is arranged on the second branch 12 between the second throttling device 121 and the pipe outlet of the condenser 2; both the first electromagnetic valve 116 and the second electromagnetic valve 122 are connected with the controller; the controller controls the flow direction of the refrigerant flowing out of the condenser 2 by controlling opening or closing of the first electromagnetic valve 116 or the second electromagnetic valve 122, and controls the refrigerant to flow through the first branch 11 or the second branch 12; and therefore, the purpose of adopting the electromagnetic valves is also to control refrigerant to switch between two flow directions.
An operation process of the heat pump system is described below:
When an environment temperature is high, the flow direction of the refrigerant is that high-temperature and high-pressure gaseous refrigerant flowing out of the compressor 4 flows through the condenser 2 and is changed into a liquid condensing agent after being condensed by the condenser 2; in this process, the condenser 2 releases heat to the outside; the liquid condensing agent enters the liquid storing device 114 through the reversing valve; the liquid storing device 114 temporarily stores the refrigerant; then the refrigerant enters the evaporator 3 from the liquid storing device 114 through the first throttling device 111; the evaporator 3 evaporates the liquid refrigerant into gaseous refrigerant; in this process, the evaporator 3 absorbs the surrounding heat; and the gaseous refrigerant enters the compressor 4 along the pipeline.
When the environment temperature is low, the flow direction of the refrigerant is that high-temperature and high-pressure gaseous refrigerant flowing out of the compressor 4 flows through the condenser 2 and is changed into the liquid condensing agent after being condensed by the condenser 2; in this process, the condenser 2 releases heat to the outside; the liquid condensing agent enters the second branch 12 through the reversing valve, enters the second throttling device 121 along the second branch 12, and then flows to the evaporator 3; the evaporator 3 evaporates the liquid refrigerant into gaseous refrigerant; in the process, the evaporator 3 absorbs the surrounding heat; and the gaseous refrigerant enters the compressor 4 along the pipeline.
Therefore, when the temperature is high, pressure load would not rise rapidly since the refrigerant is accommodated in a space of the liquid storing device 114; while at a low temperature, the compressor 4 is started, the reversing valve is first closed to return the refrigerant in the liquid storing device 114 to a refrigeration system under an effect of the compressor 4; then the reversing valve is communicated with the second branch 12, so that the refrigerant is subjected to circulation of the drying process; and the load of the compressor 4 would rise rapidly since the space for accommodating the refrigerant is reduced.
In the present embodiment, as a solution, the first throttling device 111 is a first capillary tube, and the second throttling device 121 is a second capillary tube.
In the present embodiment, as a solution, the length of the first capillary tube is smaller than that of the second capillary tube, and the second capillary tube is set to be longer in order to match a superheat degree of the evaporator 3 in a low-temperature state, thereby avoiding incomplete evaporation since a pressure rises rapidly and excessive refrigerant enters the evaporator 3.
Definitely, selection of the first throttling device 111 and the second throttling device 121 is not limited to this; electronic expansion valves may be used respectively as the first throttling device 111 and the second throttling device 121; the electronic expansion valves on the two branches are respectively connected with the controller; the electronic expansion valves regulate respective opening degrees according to command signals sent by the controller; and the opening degree of the electronic expansion valve on the first branch 11 during normal operation is greater than that of the electronic expansion valve on the second branch 12 during normal operation.
The same electronic expansion valve may also be used as the first throttling device 111 and the second throttling device 121; the electronic expansion valve is connected with the controller; the electronic expansion valve regulates the opening degree according to the command signal sent by the controller; when the system uses different branches, opening degrees of the electronic expansion valve are also different; normally, the opening degree of the electronic expansion valve when the first branch 11 is operated normally is greater that of the electronic expansion valve when the second branch 12 is operated normally.
In the present embodiment, as a solution, a first check valve 112 is arranged on the first branch 11 between the liquid storing device 114 and the first throttling device 111; and the first check valve 112 plays a role of preventing the refrigerant from flowing back into the liquid storing device 114 during operation in a low-temperature mode.
In the present embodiment, if a distance from the second electromagnetic valve 122 on the second branch 12 to the second capillary tube is large, a second check valve may also be arranged on the second branch 12 between the second throttling device 121 and the second electromagnetic valve 122, to avoid accumulating the refrigerant or lubricating oil in the pipeline in a state of high environment temperature.
In the present embodiment, as a solution, the liquid storing device 114 is a liquid storing tank, but certainly is not limited hereto; and the liquid storing device may also be selected.
The present disclosure also provides a clothes dryer, as shown in Fig. 2; the clothes dryer includes a tank body 6, an air duct 5 and a drying drum 7 mounted in the tank body 6; an air inlet 51 and an air outlet 52 of the air duct 5 are respectively connected with a rear part and a front part of the drying drum 7; the air duct 5 and the drying drum 7 form a closed loop; a fan 54 is arranged in the air duct 5; the clothes dryer further includes the above heat pump system; the evaporator 3 of the heat pump system is arranged at the air inlet 51 of the air duct 5, as a condensing device in the air duct 5, for condensing air flowing through the air duct 5; and the condenser 2 of the heat pump system is located in the air duct 5 between the fan 54 and the evaporator 3, as a heating device in the air duct 5, for heating the air flowing through the air duct 5.
In the present embodiment, as a solution, an auxiliary electric heating device 53 is arranged in the air duct 5 between the fan 54 and the air outlet 52 of the air duct 5, for further heating the air flowing through the air duct 5.
In the present embodiment, as a solution, a filter 55 is arranged at the air inlet 51 of the air duct 5; and the filter 55 can filter the air entering the air duct 5 from the drying drum 7, and prevent dander and other debris in the air from entering the air duct 5, so as to guarantee sanitation and hygiene in the air duct 5.
The drying process of the clothes dryer is that the fan 54 drives the air to flow in the air duct 5 and the drying drum 7 in a circulation manner, while the condenser 2 of the heat pump system heats the air flowing therethrough; hot air enters the drying drum 7, to evaporate out and take away water vapor in clothes; then the air containing the water vapor passes through the evaporator 3 of the heat pump system; the evaporator 3 absorbs the surrounding heat to cool the surrounding air so that the water vapor in the hot air is condensed into liquid water and is drained out of a machine along with tap water; dry air from which the water vapor is removed is reheated by the condenser 2 of the heat pump system and re-enters the drying drum 7 to dry the clothes; and this process is continuously circulated until the clothes are dried.
The present disclosure further provides a washing-drying integrated machine; the washing-drying integrated machine includes an outer drum, an air duct and an inner drum arranged in the outer drum; an air inlet and an air outlet of the air duct are respectively connected with a rear part and a front part of the outer drum; the air duct and the outer drum form a closed loop; and a fan is arranged in the air duct. The washing-drying integrated machine further includes the heat pump system according to any of the above; the evaporator 3 of the heat pump system is arranged at the air inlet of the air duct, as a condensing device in the air duct, for condensing the air flowing through the air duct; and the condenser 2 of the heat pump system is located in the air duct between the fan 54 and the evaporator 3, as a heating device in the air duct, for heating the air flowing through the air duct.
In the present embodiment, as a solution, an auxiliary electric heating device is arranged in the air duct between the fan and the air outlet of the air duct, for further heating the air flowing through the air duct.
The drying process of the washing-drying integrated machine is similar to the drying process of the clothes dryer, and is not repeatedly described here.

Claims

A heat pump system for drying clothes in a clothes dryer or in a washing-drying integrated machine, comprising an evaporator (3), a compressor (4), a condenser (2) and a refrigerant regulating subsystem (1), wherein the evaporator (3), the compressor (4), the condenser (2) and the refrigerant regulating subsystem (1) are sequentially communicated through a pipeline to form a refrigerant circulating loop; and the refrigerant regulating subsystem (1) comprises a first branch (11) and a second branch (12) connected in parallel between the evaporator (3) and the condenser (2);
the first branch (11) comprises a first throttling device (111) having an outlet connected with a pipe inlet of the evaporator (3), and a liquid storing device (114) located between the first throttling device (111) and the condenser (2);
the second branch (12) comprises a second throttling device (121); and
wherein electromagnetic valves (116, 122) are respectively arranged on the first branch (11) between the condenser (2) and the liquid storing device (114) and on the second branch (12) between the second throttling device (121) and the condenser (2);
characterized in that check valves (112) are respectively arranged on the first branch (11) between the liquid storing device (114) and the first throttling device (111) and the second branch (12) between the second throttling device (121) and the electromagnetic valve (122).
The heat pump system according to claim 1, wherein the second branch (12) and the first branch (11) are connected with a pipe outlet of the condenser (2) through a reversing valve.
The heat pump system according to claim 1, wherein the first throttling device (111) is a first capillary tube; the second throttling device (121) is a second capillary tube; and the length of the first capillary tube is smaller than that of the second capillary tube.
The heat pump system according to claim 1, wherein the first throttling device (111) and the second throttling device (121) are a same electronic expansion valve; and an opening degree of the electronic expansion valve is adjustable.
The heat pump system according to claim 1, wherein both the first throttling device (111) and the second throttling device (121) are electronic expansion valves; and opening degrees of all the electronic expansion valves are adjustable.
A washing-drying integrated machine, comprising an outer drum, an air duct (5) and an inner drum arranged in the outer drum, wherein an air inlet and an air outlet of the air duct (5) are respectively connected with a rear part and a front part of the outer drum; the air duct and the outer drum form a closed loop; a fan (54) is arranged in the air duct (5), wherein the washing-drying integrated machine further comprises the heat pump system according to any of claims 1-5; the evaporator (3) of the heat pump system is arranged at the air inlet of the air duct (5), for cooling down air flowing through the air duct (5), and condensing water vapor comprised in the air ; and the condenser (2) of the heat pump system is located in the air duct (5) between the fan (54) and the evaporator (3), for heating air flowing through the air duct (5).
A clothes dryer, comprising a tank body (6), an air duct (5) and a drying drum (7) mounted in the tank body (6), wherein an air inlet (51) and an air outlet (52) of the air duct (5) are respectively connected with a rear part and a front part of the drying drum (7) to form a closed loop together with the drying drum (7); a fan (54) is arranged in the air duct (5), wherein the clothes dryer further comprises the heat pump system according to any of claims 1-5; the evaporator (3) of the heat pump system is arranged at the air inlet (51) of the air duct (5), for cooling down air flowing through the air duct (5), and condensing water vapor comprised in the air ; and the condenser (2) of the heat pump system is located in the air duct (5) between the fan (54) and the evaporator (3), for heating air flowing through the air duct (5).
The clothes dryer according to claim 7, wherein an auxiliary electric heating device (53) is arranged in the air duct (5) between the fan (54) and the air outlet (52) of the air duct (5).