WO2009016173A1

WO2009016173A1 - A washer/dryer

Info

Publication number: WO2009016173A1
Application number: PCT/EP2008/059926
Authority: WO
Inventors: Umut Esat Ozturk
Original assignee: Arcelik Anonim Sirketi
Priority date: 2007-08-02
Filing date: 2008-07-29
Publication date: 2009-02-05
Also published as: EP2171150B1; DE602008003446D1; ATE487821T1; ES2352637T3; EP2171150A1

Abstract

The present invention relates to a washer/dryer (1) that can operate at low energy, fast drying and hygienic drying modes by maintaining different levels of pressure and temperature decreases of the refrigerant fluid between the condenser (4) and the evaporator (3) by means of using a valve (7) and at least two throttle elements (8, 108) between the condenser (4) and the evaporator (3).

Description

A WASHER/DRYER

[0001] The present invention relates to a washer/dryer of which the drying effectiveness is increased.

[0002] In washer/dryers, particularly in heat pump drying machines, the drying air circulates along a closed cycle. The humidity and temperature values of this air is changed by the heat exchange units over which it passes during the drying cycle and drying is performed by absorbing the humidity of the item while passing through the region containing the items to be dried. In the widely used implementation of the drying process an evaporator (cold heat exchanger) that cools and dehumidifies the humid air, a condenser (hot heat exchanger) that heats the air are provided on the path the air follows, a drum wherein the item to be dried contacts with air and a fan that keeps the air in circulation during the drying cycle. Furthermore, a closed fluid cycle is present in the system. In this cycle maintained by pipes that passes over the condenser and the evaporator, throttle elements such as the capillary tubes or expansion valve for adjusting the temperature, pressure and flow direction of the fluid, and direction valves and a compressor are provided.

[0003] In heat pump washer/dryers, drying can be performed at different temperatures and in different durations. When drying is performed at a low temperature, energy consumption is reduced but the drying duration is prolonged and the dried laundry is not hygienic. When a fast and hygienic drying is preferred, then energy consumption increases. Therefore, in washer/dryers that operate in a single mode, the intended result cannot be attained in at least one of washing/drying duration, hygiene and consumed energy variables. Moreover, the user does not have the choice of making a selection in accordance with the current conditions. Various implementations have been developed wherein heat exchange elements are used in different configurations in washer/dryers in order to overcome these problems encountered during usage.

[0004] In the state of the art Japanese Patent Document No JP 2005224492, a heat pump washer/dryer is disclosed wherein the compressor is placed before the evaporator, between the evaporator and the condenser or after the condenser according to the air flow direction. Thus, heat loss is decreased by including the air expelled from the compressor in the drying air. Moreover, in this document there is mention of a bi-directional valve positioned parallel to the throttle element in the passageway from the condenser to the evaporator for by-passing the flow passing through the throttle element. As a result, the temperature of the fluid delivered to the compressor and hence the temperature and pressure of fluid leaving the compressor is increased and the drying duration is shortened.

[0005] In the state of the art Japanese Patent Document No JP1212599 a washer/dryer is explained wherein the amount and the path followed by the fluid between the evaporators is changed by a control valve and the drying process is performed in two different modes.

[0006] In the state of the art European Patent Document No EP1154065 is about a heat pump dryer, in this document an embodiment is explained wherein an electric heater is used in addition to the present drying system and the control is provided by means of sensors.

[0007] The aim of the present invention is the realization of a washer/dryer having a high drying performance that selectively performs fast hygienic drying and low energy consumption programs.

[0008] The washer/dryer realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a drum wherein the laundry is emplaced, an evaporator that gasifies the refrigerant fluid by vaporizing, a condenser that liquefies the refrigerant fluid by condensing, a fan providing the drying air flow, a compressor, directional valves used for determining the flow paths of the refrigerant fluid and throttle elements that decrease the pressure and temperature of the refrigerant fluid.

[0009] In the washer/dryer of the present invention, at least two throttle elements and at least one valve are provided between the condenser and the evaporator. The refrigerant fluid is enabled to follow different paths in reaching from the condenser to the evaporator by means of the valve and by passing on this path through, at least one, throttle elements of different numbers and/or qualifications thereby controlling the drying rate and respectively the amount of energy consumption. Thus, the washer/dryer is enabled to operate at different modes.

[0010] The refrigerant fluid passes through at least two different throttle elements by using the valve as desired. Thus, the heat pump is operated at two different modes and the drying process is performed at two different modes by maintaining decreases at least in two different levels of temperature and pressure. One of these modes is adjusted to provide low energy consumption and the other to provide fast drying.

[0011] In an embodiment of the present invention, at least one bi-directional valve is provided between the condenser and the evaporator and at least two throttle elements that are connected in parallel. In this embodiment, since the throttle elements are capillary tubes of different sizes and/or diameters, the refrigerant element passes over the throttle elements by means of the valve, providing temperature and pressure decreases in at least two different levels.

[0012] By passing the fluid through throttle elements of different qualifications and/or through paths formed by connecting these elements in different parallel/series combinations, the pressure of the fluid entering the evaporator and the compressor is changed. Thus, the drying air temperature, the moisture contained therein and the capacity to absorb heat energy can be adjusted and drying is performed by consuming less energy when desired.

[0013] In another embodiment of the present invention, preferably at least one electric heater is provided in the drying cycle. When desired, the heater can be activated for performing fast and hygienic drying for selectively and effectively maintaining fast and hygienic drying.

[0014] In another embodiment of the present invention, the condenser used previously as a single piece is divided into two and an additional valve and at least one throttle element are provided therebetween. In the case the fluid passage between condensers is maintained without visiting any one throttle element, the drying process can be performed as when the condenser is a single piece. When the fluid passage between condensers is maintained through at least one throttle element, the evaporator and the other connected condenser are used as the cold heat exchanger. The refrigerant fluid leaving the second condenser passes through at least one throttle on the way to the evaporator, thus temperature and pressure can be decreased one step further. Consequently, the previous function of the evaporator by itself is performed by the evaporator and the second condenser together. In this case, since only the first condenser functions as the hot heat exchanger, performance thereof is lower than the previous one. On the other hand, the temperature of the drying air can be raised as much as desired by adding a heater to the drying cycle. By reinforcing with a heater, temperature of air is raised further and the moisture holding capacity of air entering the drum is increased. With this embodiment a faster drying is provided.

[0015] In the embodiment wherein the condenser is used by dividing into two, while the path followed by the refrigerant fluid in the drying cycle is changed by utilizing multi-directional valves, the exchanger surface areas functioning as the evaporator and condenser are also changed thereby changing the heat energy expelled by the condenser and the heat energy absorbed by the evaporator.

[0016] In the embodiments explained above, the drying process can be performed in a greater number of different modes instead of two by using multi-directional valves and more than two throttle elements. Thus, drying can be performed at different ambient temperatures consuming less energy or providing a faster drying.

[0017] The washer/dryer of the present invention can selectively perform drying with low energy consumption or very fast drying when desired at different ambient temperatures or conditions according to various laundry amounts or types by using multi-directional valves, throttle elements or heaters in different profiles. Depending on choice, hygienic drying can be provided at a high temperature as a different program or by including in the drying program. Thus, hygienic drying with low energy or fast and hygienic drying can be performed.

[0018] The washer/dryer realized in order to attain the aim of the present invention is illustrated in the attached figures, where: [0019] Figure 1 - is the schematic view of the embodiment wherein the throttle elements are connected in parallel. [0020] Figure 2 - is the schematic view of the embodiment wherein the throttle elements are connected in series. [0021] Figure 3 - is the schematic view of the embodiment wherein the condenser is divided into two. [0022] Figure 4 - is the schematic view of another embodiment wherein the condenser is divided into two. [0023] The elements illustrated in the figures are numbered as follows:

1. Washer/dryer

2. Drum

3. Evaporator

4. 104, 204 Condenser

5. Fan

6. Compressor

7. 107, Valve

8. 108, Throttle element

[0024] The washer/dryer (1) of the present invention, preferably a heat pump dryer, comprises a drum (2) wherein the item to be dried contacts with air in a closed cycle in which the air flows in a certain direction, an evaporator (3) (cold heat exchanger) that cools and dehumidifies the warm and humid air passing over, at least one condenser (4) (hot heat exchanger) that heats the air passing thereover, and a fan (5) that maintains continuation in circulation of air during the cycle.

[0025] Depending on the air flow direction, warm and saturated air exiting the drum (2) loses moisture and the temperature falls as a result of passing through the evaporator (3). The cool air with low humidity passing over the evaporator (3) rises in temperature by passing through the condenser (4). Thus, the warm and humid air leaving the drum (2) as a result of passing through the evaporator (3) and the condenser (4) in that order becomes less humid and hotter by leaving the condenser (4) and entering the drum (2) again. The less humid and hot air entering the drum (2) contacts with the items to be dried in the drum (2). As a result of this contact, the air becomes more humid and cold and the temperature of the item to be dried increases and the amount of humidity decreases. As this process is repeated by the air circulating in the cycle, drying of the item in the drum (2) is performed.

[0026] The washer/dryer (1) comprises a compressor (6) used for increasing the temperature and pressure of the refrigerant fluid, at least two throttle elements (8, 108) of different numbers and/or qualifications, disposed between the condenser (4) and the evaporator (3) and at least one valve (7) situated prior to the throttle elements (8, 108) between the condenser (4) and the evaporator (3), controlled such that the fluid passes through at least one of the throttle elements (8, 108) to reach the evaporator (3).

[0027] The refrigerant fluid passes through the evaporator (3), the compressor, at least one condenser (4), at least one valve (7, 107) and at least one throttle element (8, 108). As the temperature and pressure of the fluid decreases while passing through the evaporator (3) and the compressor (6), the temperature and pressure increases while passing through the evaporator (3) and the compressor (6) and the cycle continues thus. Heat transfer occurs between the fluid and the air passing through the condenser (4) and the evaporator (3) and thus the humidity and temperature of the air passing through the condenser (4) and the evaporator (3) changes as explained above.

[0028] For the aim of attaining different modes whereat the washer/dryer (1) can operate, the refrigerant fluid is enabled to complete the refrigerant cycle from different paths and passing through, at least one, throttle elements (8, 108) of different numbers and/or qualifications on this path. The fluid passes through the throttle elements (8, 108) of different qualifications and/or paths formed by these elements (8, 108) being connected in different parallel/series combinations by means of the valve (7) situated between the condenser (4) and the evaporator (3) and at least two throttle elements (8, 108). Thus different pressure and temperature decreases are maintained in the fluid and the drying process is performed in at least two different conditions. [0029] In an embodiment of the present invention (Figure 1), two throttle elements (8, 108) on two different paths being parallel to each other and a bi-directional valve (7) is used between the condenser (4) and the evaporator (3). The refrigerant fluid is made to pass over any one of the throttle elements (8, 108) by using the bi-directional valve (7) to direct the fluid to different paths. Since the throttle elements (8, 108) are qualified to maintain temperature and pressure decrease at two different levels, the washer/dryer (1) can operate at two different modes and the drying process can be performed at two different conditions. For example, the throttle elements (8, 108) are capillary tubes having different diameters and/or lengths. The alternative of the fluid passing through the path wherein the temperature and pressure decrease will be more can be adjusted as the fast drying mode and the alternative of passing through the path wherein temperature and pressure decrease will be less as the mode providing low energy consumption.

[0030] In an embodiment of the present invention (Figure 2) the said throttle elements (8, 108) are placed in series so that the washer/dryer (1) operates at two different modes and the drying process is performed at two different modes. In this embodiment, the valve (7) maintains the refrigerant fluid to pass over only one throttle element (108) or from both of the throttle elements (8, 108). Thus, temperature and pressure decreases are provided at two different levels.

[0031] In an embodiment of the present invention (Figure 3) the washer/dryer (1) comprises two condensers (104, 204). These two condensers (104, 204) are disposed in series on the flow path of the refrigerant fluid. The fluid passes from the first condenser (104), the second condenser (204) and the evaporator (3) in that order. A valve (7) and a throttle element (8) are provided between the condensers (104, 204). Another throttle element (108) is situated between the second condenser (204)) and the evaporator (3). The valve (7) directs the refrigerant fluid from the first condenser (104) to the second condenser (204) directly or over the throttle element (8). In the case the fluid is delivered directly from the first condenser (104) to the second condenser (204), both of the condensers (104, 204) function as hot heat exchangers. In the case the fluid passes over the throttle element (8), the second condenser (204) functions as a cold heat exchanger. Temperature and pressure decreases one step further in the fluid that leaves the second condenser (204) by passing again through the throttle element (108).

[0032] In another embodiment of the present invention (Figure 4), a throttle element (108) and a valve (7) are added between the second condenser (204) and the evaporator (3). The valve (7) directs the refrigerant fluid from the second condenser (204) to the evaporator (204) directly or over the throttle element (108). Thus the throttle elements (8, 108) can be used by connecting in series or parallel. Consequently, the fluid reaches from the first condenser (104) to the evaporator (3) passing through both throttle elements (8, 108) or only over the throttle element (8) between the first condenser (104) and the second condenser (204) or over the throttle element (108) between the second condenser (204) and the evaporator (3). Thus, the washer/dryer (1) can be operated by choosing one of the modes of low energy consumption, fast drying or hygienic drying.

[0033] In yet another embodiment of the present invention, the washer/dryer (1) comprises a heater disposed between the condensers (4 and 104). The heater increases drying performance and plays a role in performing fast drying. Using the heater and disposing the compressor (6) after the evaporator (3) or the condenser (4) can be applied at the same time and the hygienic drying mode can be thus performed. Temperature increases when the heater is activated for fast drying. However, the heat received from the evaporator (3) has to be increased also. To this end, the valve (7) directs the refrigerant fluid from the first condenser (104) to the second condenser (204) over the throttle element (8). Thus, the second condenser (204) functions as a cold heat exchanger.

[0034] In another embodiment of the present invention, the compressor (6) is disposed on the flow path of drying air, after the evaporator (3) or the condenser (4) depending on the air flow direction. Thus, the heat energy generated from the compressor (6) is used in heating the drying air and the drying performance of the washer/dryer (1) is increased. In the washer/dryer (1) of the present invention, different levels of decreases in the pressure and temperature of the refrigerant fluid are provided by using a valve (7) and at least two throttle elements (8) between the condenser (4) and the evaporator (3). Consequently, the washer/dryer (1) can be operated at various modes such as fast and low energy consumption.

Claims

1. A washer/dryer (1) that comprises a drum (2) wherein the item to be dried contacts with air, an evaporator (3) that cools and dehumidifies the warm and humid air passing over, at least one condenser (4, 104, 204) that heats the air passing thereover, a fan (5) that maintains continuation in circulation of the air during the cycle and a compressor (6) that pumps the refrigerant fluid and characterized by at least two throttle elements (8, 108) of different numbers and/or qualifications, disposed between the condenser (4) and the evaporator (3) and at least one valve (7) situated prior to the throttle elements (8, 108) between the condenser (4) and the evaporator (3) controlled such that the fluid reaches the evaporator (3) by passes through at least one of the throttle elements (8, 108).

2. A washer/dryer (1) as in Claim 1 , characterized by the throttle elements (8, 108) disposed parallel to each other such that temperature and pressure decrease is maintained at two different levels.

3. A washer/dryer (1) as in Claim 1 , characterized by the throttle elements (8, 108) disposed in series and the valve (7) that maintains the refrigerant fluid to pass over only one throttle element (108) or over both of the throttle elements (8, 108).

4. A washer/dryer (1) as in Claim 1 , characterized by at least two condensers (104, 204) connected in series to each other and the valve (7) disposed between the condensers (104, 204) such that the fluid passes from the first condenser (104) to the second condenser (204) directly or over the throttle element (8) and the throttle element (108) situated between the second condenser (204) and the evaporator (3).

5. A washer/dryer (1) as in Claim 4, characterized by the valve (107) and the throttle element (108) disposed between the second condenser (204) and the evaporator (3) such that the fluid passes from the second condenser (204) to the evaporator (3) directly or over the throttle element (108).