WO2014086831A1

WO2014086831A1 - A laundry dryer comprising a filter

Info

Publication number: WO2014086831A1
Application number: PCT/EP2013/075488
Authority: WO
Inventors: Yavuz Sahin; Onur Hartoka; Celal Vatansever; Umit PEHLIVAN
Original assignee: Arcelik Anonim Sirketi
Priority date: 2012-12-04
Filing date: 2013-12-04
Publication date: 2014-06-12
Also published as: EP2929078A1

Abstract

The present invention relates to a laundry dryer (1) comprising a body (2), a drum (3) wherein laundry to be dried is placed, an air circulation duct (4) providing the processing air (PA) to be sent onto the laundry in the drum (3), a filter (5) disposed on the air circulation duct (4) and that holds the particles like fiber and lint in the processing air (PA) blown onto the laundry by the fan and at least one sensor (6) disposed in the drum (3) or on the air circulation duct (4) and that detects the changes in the state of the processing air (PA).

Description

A LAUNDRY DRYER COMPRISING A FILTER

The present invention relates to a laundry dryer comprising a filter that holds the particles like fiber and lint in the drying air.

Nowadays there are two types of widely used dryers known as open cycle and closed cycle. In open cycle dryers, the temperature of the processing air (PA) sucked by means of a fan from the ambient is increased by being passed over the heater. While the processing air (PA), the temperature of which is increased by being heated, is being passed over the wet laundry inside the drum, it provides the water contained in the laundry to evaporate. The processing air (PA) passing through the drum is sent to the outer environment together with the water vapor evaporated from the laundry by means of an exhaust apparatus. In the second type of dryers, in other words in closed system dryers, two different systems are used. These systems are heat pump and air-cooled. In heat pump laundry dryers, the heat pump used for drying the laundry is composed of flow tubes through which the refrigerant circulates, a compressor that provides the circulation of the refrigerant by pressurizing it, an evaporator and a condenser, and the drying process is performed by passing the processing air (PA) over the laundry. The condenser located in the heat pump functions as a heater and the evaporator as a condenser. The processing air (PA) heats up while passing from the condenser, delivered onto the laundry in a heated state and after dehumidifying the laundry, leaves its humidity while passing over the evaporator. In closed cycle, air-cooled laundry dryers, the drying process is performed by the interaction of the cooling air and the processing air (PA) which does not directly contact each other. The processing air (PA) is heated by means of a heater and directed into the drum, which then contacts the damp laundry and dehumidifies the laundry and which is finally delivered to a condenser to be dehumidified. Meanwhile, the cooling air is sent onto the condenser by means of a fan and thus, the moisture in the processing air (PA) is provided to be condensed by the condenser being cooled. After being dehumidified on the condenser, the processing air (PA) is heated by the heater and sent to the drum by being included again into the drying cycle with low relative humidity rate and at high temperature. In dryers, the heated air is directed into the drum containing the articles to be dried and is sucked to be sent again into the heating cycle. During this cycle of air, the particles like fiber and lint should be held. To this end, various filters are developed for holding these particles in dryers. During the operation of the dryer, these filters perform their function of holding the particles in the environment. However, these filters enabling the processing air (PA) to be filtered lead to pressure loss in the processing air (PA) and cause the flow rate of the processing air (PA) to decrease. Thus, the energy consumption of the laundry dryer increases.

In the state of the art German Patent Application No. DE4304372, a filter is explained that is used in the lid and the evaporator inlet in order to prevent the clogging of the heat exchangers with fibers in a closed cycle dryer with heat pump.

In the state of the art International Patent Application No. WO2011042345, a self cleaning filter mechanism is explained.

The aim of the present invention is the realization of a laundry dryer wherein energy saving is provided.

The laundry dryer realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof comprises a body, a drum wherein the laundry to be dried is placed, an air circulation duct enabling the processing air (PA) to be sent onto the laundry in the drum, at least one filter disposed on the air circulation duct, that holds the particles like fiber and lint in the processing air (PA) blown by the fan and at least one sensor that measures the changes in the state of the processing air (PA). Furthermore, a control unit is disposed inside the body that changes the filter to the closed position (C) wherein the filter filters the processing air (PA) passing through the air circulation duct or that changes the filter to the open position (O) wherein the filter does not prevent the flow of the processing air (PA) in the air circulation duct depending on the data received from the sensor.

In an embodiment of the present invention, the control unit provides the filter to be changed to the closed position (C) depending on the relative humidity in the processing air (PA) measured by the sensor.

In an embodiment of the present invention, the control unit provides the filter to be changed to the closed position (C) depending on the temperature in the processing air (PA) measured by the sensor.

In a derivative of the embodiment of the present invention, temperature change can be observed in the processing air (PA) passed over the laundry in the drum. The temperature change difference in the processing air (PA) being high shows that the laundry is damp/wet. Thanks to the two sensors disposed before and after the drum with respect to the flow direction of the processing air (PA), the drum entry temperature (T₁) of the processing air (PA) and the drum exit temperature (T₂) of the processing air (PA) are measured. The filter is activated by the control unit when the difference (∆T) between the drum entry and exit temperatures (T₁ and T₂) of the processing air (PA) decreases.

In an embodiment of the present invention, the control unit provides the filter to be changed to the closed position (C) depending on the limit values (∆V) (temperature, time, relative humidity rate, etc.) determined by the manufacturer according to the drying program. Before starting the machine, the user can decide which drying program (combed cotton, toweling, polar etc.) to use. The drying program can be automatically selected by the machine. Predetermined limit values (∆V) are saved in the control unit for each program. Thus, the filter is activated at different limit values in different programs.

In a derivative of the embodiment of the present invention, the control unit provides the filter to be changed to the closed position (C) depending on the predefined limit time values (∆ʈ) according to the drying program. Thus, the filter is kept at the closed position (C) at the limit time value (∆ʈ) predetermined by the manufacturer for each program.

In an embodiment of the present invention, the laundry dryer performs the drying process in three main phases. First of these is the heating phase (P1) wherein the processing air (PA) is heated by means of a heater, second one is the drying phase (P2) wherein the temperature of the processing air (PA) is almost constant after the heating phase (P1) and the third one is the airing phase (P3) wherein the temperature of the processing air (PA) decreases gradually. The filter is changed to the closed position (C) by the control unit at the end of the heating phase (P1) and/or at the beginning of the drying phase (P2). The control unit changes the filter to the closed position (C) at the end of the heating phase (P1) of the processing air (PA) and keeps the filter in the closed position (C) until the end of the airing phase (P3).

In an embodiment of the present invention, the filter has the open position (O) that enables the processing air (PA) passing through the air circulation duct to pass through the air circulation duct without being filtered and wherein the filter is parallel to the air circulation duct and the closed position (C) that enables the processing air (PA) to be filtered, to which the filter is brought from the open position (O) by being rotated and wherein the filter is almost perpendicular to the air circulation duct. Thus, while effectively filtering the processing air (PA) in the closed position (C), the filter does not prevent the flow of the processing air (PA) in the open position (O) and enables the laundry dryer to operate efficiently.

In an embodiment of the present invention, the filter is disposed in the air circulation duct before the condenser with respect to the flow direction of the processing air (PA). Thus, the condenser that provides the condensation of the processing air (PA) is prevented from clogging or the efficiency thereof is prevented from decreasing.

In an embodiment of the present invention, the sensor detects the particle density in the processing air (PA). Thus, in the case foreign substances like hair, lint, etc. are observed in the processing air (PA) that circulates in the air circulation duct, the control unit changes the filter to the closed position (C).

In the laundry dryer of the present invention, energy saving is provided by means of the control unit that provides the filter to be changed to the closed position (C) or to the open position (O) depending on the density of the foreign substances such as hair, lint, etc. in the processing air (PA).

In the laundry dryer of the present invention, energy saving is provided by means of the filter which has the open position (O).

The laundry dryer realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

Figure 1 – is the schematic view of a laundry dryer when the filter is in the closed position (C).

Figure 2 – is the schematic view of a laundry dryer when the filter is in the open position (O).

The elements illustrated in the figures are numbered as follows:

Laundry dryer
Body
Drum
Air circulation duct
Filter
Sensor
Control unit
Condenser

The laundry dryer (1) comprises a body (2), a drum (3) wherein laundry to be dried is placed, an air circulation duct (4) providing the processing air (PA) to be sent onto the laundry in the drum (3), at least one filter (5) disposed on the air circulation duct (4) and that holds the particles like fiber and lint in the processing air (PA) blown onto the laundry and at least one sensor (6) disposed in the drum (3) or on the air circulation duct (4) and that detects the changes in the state of the processing air (PA).

The laundry dryer (1) of the present invention furthermore comprises a control unit (7) that provides the filter (5) to be changed to an open position (O) that enables the processing air (PA) passing through the air circulation duct (4) to pass through the air circulation duct (4) without being filtered and a closed position (C) that enables the processing air (PA) to be filtered depending on the data received from the sensor (6) (Figure 1, Figure 2).

During the operation of the laundry dryer (1), fiber, lint and hair coming off the laundry accumulate in the processing air (PA) that circulates in the air circulation duct (4) in the course of time. The density of the foreign substances like hair, lint, etc. in the processing air (PA) changes depending on the type of the laundry dried or the drying phase. In the case the density of the foreign substances in the processing air (PA) is high; the control unit (7) activates and changes the filter (5) to the closed position (C). Thus, the processing air (PA) passing through the air circulation duct (4) is filtered. Otherwise, the control unit (7) keeps the filter (5) in the open position (O) and thus enables the processing air (PA) to pass through the air circulation duct (4) without pressure and flow rate losses generated by the filter (5) in the processing air (PA). Thus, the filter (5) that does not continuously remain in the closed position (C) while the machine is operating prevents the energy consumption of the machine from increasing.

In an embodiment of the present invention, the control unit (7) provides the filter (5) to be changed to the closed position (C) depending on the relative humidity measured in the processing air (PA) by the sensor (6). By means of a sensor (6) disposed in the air circulation duct (4) or the drum (3), the relative humidity rate in the processing air (PA) during the drying process is measured. The relative humidity rate in the processing air (PA) varies depending on the type of the laundry (combed cotton, toweling, polar, etc.) in the dryer (1) and/or on the dampness of the laundry in the machine. While damp, wet laundry leaves a lesser amount of foreign substances like hair, lint, etc., the drying or dry laundry leaves a higher amount of foreign substances. When the machine is operated by the user, high relative humidity values are measured in the processing air (PA) passed over wet laundry in the drum (3). By the processing air (PA) being heated and passed over the laundry again and again, a non-linear decrease is started to be observed in the high humidity rate after a point. When the humidity rate transmitted by the sensor (6) reaches the point predetermined by the manufacturer, the control unit (7) provides the processing air (PA) to be filtered by changing the filter (5) to the closed position (C). Thus, by the filter (5) remaining in the open position (O) in the case the density of the foreign substances like hair, lint, etc. is low or very close to zero, pressure loss and flow rate decrease in the processing air (PA) of the filter (5) are prevented. Thus, the energy consumption of the laundry dryer (1) is decreased.

In an embodiment of the present invention, the control unit (7) provides the filter (5) to be changed to the closed position (C) depending on the temperature of the processing air (PA) measured by the sensor (6). During the drying process of the laundry in the laundry dryer (1), the temperature of the processing air (PA) varies. The control unit (7) provides the filter (5) to be changed to the closed position (C) or to remain in the open position (O) by comparing the temperature value information predetermined by the manufacturer with the information received from the sensor (6).

In a derivative of this embodiment, the drum (3) entry temperature (T₁) of the processing air (PA) and the drum (3) exit temperature (T₂) of the processing air (PA) are measured by means of the two sensors (6) placed at the drum (3) inlet and exit ports. The difference (∆T) between the said two temperature values being high shows that laundry is wet/damp. The filter (5) is activated by the control unit (7) when the difference (∆T) between the drum (3) entry and exit temperatures of the processing air (PA) decreases.

In an embodiment of the present invention, the control unit (7) provides the filter (5) to be changed to the closed position (C) depending on the predefined limit values (∆V) according to the drying program. Before starting the laundry dryer (1), the user can decide the desired drying program (combed cotton, toweling, polar etc.) to be executed by the laundry dryer (1). The drying program can be also automatically selected by the laundry dryer (1). Predetermined limit values (∆V) are saved in the control unit (7) for each program. Thus, the filter (5) is activated at different limit values in different programs.

In a derivative of this embodiment, the control unit (7) provides the filter (5) to be changed to the closed position (C) depending on the predefined limit time values (∆ʈ) according to the drying program. Thus, the filter (5) is kept at the closed position (C) at the limit time value (∆ʈ) predetermined by the manufacturer for each program.

In an embodiment of the present invention, the laundry dryer (1) performs the drying process in three main phases. First of these is the heating phase (P₁) wherein the processing air (PA) is heated by means of a heater, second one is the drying phase (P₂) wherein the temperature of the processing air (PA) is almost constant after the heating phase (P₁) and the third one is the airing phase (P₃) wherein the temperature of the processing air (PA) decreases gradually. The filter (5) is changed to the closed position (C) by the control unit (7) at the end of the heating phase (P₁) and/or at the beginning of the drying phase (P₂). The control unit (7) changes the filter (5) to the closed position (C) at the end of the heating phase (P₁) of the processing air (PA) and keeps the filter (5) in the closed position (C) until the end of the airing phase (P₃).

In an embodiment of the present invention, the filter (5) has an open position (O) that enables the processing air (PA) passing through the air circulation duct (4) to pass through the air circulation duct (4) without being filtered and wherein the filter (5) is parallel to the air circulation duct (4) and a closed position (C) that enables the processing air (PA) to be filtered, to which the filter (5) is brought from the open position (O) by being rotated and wherein the filter (5) is almost perpendicular to the air circulation duct (4). Thus, while effectively filtering the processing air (PA) in the closed position (C), the filter (5) does not prevent the flow of the processing air (PA) in the open position (O) and provides the laundry dryer (1) to operate efficiently.

In an embodiment of the present invention, the laundry dryer (1) comprises a condenser (8). The filter (5) is disposed in the air circulation duct (4) before the condenser (8) with respect to the flow direction of the processing air (PA). Thus, the condenser (8) that provides the condensation of the processing air (PA) is prevented from clogging or the efficiency thereof is prevented from decreasing.

In an embodiment of the present invention, the sensor (6) detects the particle density in the processing air (PA). Thus, in the case foreign substances like hair, lint, etc. are observed in the processing air (PA) that circulates in the air circulation duct (4), the control unit (7) changes the filter (5) to the closed position (C).

In an embodiment of the present invention, the sensor (6) is a conductivity sensor.

In an embodiment of the present invention, the sensor (6) is a temperature sensor.

In the laundry dryer (1) of the present invention, energy saving is provided by means of the control unit (7) that provides the filter (5) to be changed to the closed position (C) or to the open position (O) depending on the density of the foreign substances such as hair, lint, etc. in the processing air (PA).

Claims

A laundry dryer (1) comprising a body (2), a drum (3) wherein laundry to be dried is placed, an air circulation duct (4) providing the processing air (PA) to be sent onto the laundry in the drum (3), at least one filter (5) disposed on the air circulation duct (4) and that holds the particles like fiber and lint in the processing air (PA) blown onto the laundry and at least one sensor (6) disposed in the drum (3) or on the air circulation duct (4) and that detects the changes in the state of the processing air (PA), characterized by the control unit (7) that provides the filter (5) to be changed to an open position (O) that enables the processing air (PA) passing through the air circulation duct (4) to pass through the air circulation duct (4) without being filtered and a closed position (C) that enables the processing air (PA) to be filtered depending on the data received from the sensor (6).
A laundry dryer (1) as in Claim 1, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) depending on the relative humidity measured in the processing air (PA) by the sensor (6).
A laundry dryer (1) as in Claim 1, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) depending on the temperature of the processing air (PA) measured by the sensor (6).
A laundry dryer (1) as in Claim 1, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) depending on the difference (∆T) between the drum (3) entry temperature (T₁) and the drum (3) exit temperature (T₂) of the processing air (PA).
A laundry dryer (1) as in any one of the above claims, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) depending on the predetermined limit values (∆V) according to the drying program.
A laundry dryer (1) as in any one of the above claims, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) depending on the predetermined limit time values (∆ʈ) according to the drying program.
A laundry dryer (1) as in any one of the above claims, characterized by the control unit (7) that provides the filter (5) to be changed to the closed position (C) at the end of the heating phase (P₁) of the processing air (PA).
A laundry dryer (1) as in any one of the above claims, characterized by the filter (5) having an open position (O) that enables the processing air (PA) passing through the air circulation duct (4) to pass through the air circulation duct (4) without being filtered and wherein the filter (5) is parallel to the air circulation duct (4) and a closed position (C) that enables the processing air (PA) to be filtered, to which the filter (5) is brought from the open position (O) by being rotated and wherein the filter (5) is almost perpendicular to the air circulation duct (4).
A laundry dryer (1) as in any one of the above claims, characterized by a condenser (8) and the filter (5) disposed in the air circulation duct (4) before the condenser (8) with respect to the flow direction of the processing air (PA).
A laundry dryer (1) as in Claim 1, characterized by the sensor (6) that detects the particle density in the processing air (PA).
A laundry dryer (1) as in any one of the above claims, characterized by the sensor (6) which is a conductivity sensor.
A laundry dryer (1) as in any one of the above claims, characterized by the sensor (6) which is a temperature sensor.