EP3887734A1

EP3887734A1 - A cooling device wherein the frost formation in the freezing compartment is prevented

Info

Publication number: EP3887734A1
Application number: EP19798577.3A
Authority: EP
Inventors: Alper AKDEMIR; Can Erkey; Metin Kaya; Mustafa Altintas; Sinan KALECI
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2018-11-26
Filing date: 2019-11-01
Publication date: 2021-10-06
Anticipated expiration: 2039-11-01
Also published as: WO2020108916A1; EP3887734B1; PL3887734T3

Abstract

The present invention relates to a cooling device (1) comprising at least one freezing compartment (2); at least one evaporator (3) which transfers heat with the air in the freezing compartment (2) so as to keep the freezing compartment (2) at the desired temperature; and at least one fan (4) which disperses the air, which is brought to the desired temperature by means of the evaporator (3), in the freezing compartment (2).

Description

A COOLING DEVICE WHEREIN THE FROST FORMATION IN THE FREEZING COMPARTMENT IS PREVENTED

The present invention relates to a cooling device wherein the frost formation in the freezing compartment is prevented.
In cooling devices such as conventional domestic refrigerators, a cooling circuit is provided, which at least comprises a compressor, a condenser, a capillary, an evaporator which are serially arranged and fluidly connected to one another by respective lines for circulating a refrigerant. The refrigerant which is circulated through the evaporator cools the respective surfaces of the evaporator. As the temperature of the evaporator surfaces decrease, the ambient vapor inside the compartment starts to condense on the evaporator surfaces and forms frost due to the low ambient temperature. Since the frost has a relatively low heat transfer coefficient, the cooling performance of the cooling device decreases while the energy consumption increases. Therefore, in the state of the art, a defrost process is performed at certain intervals in order to remove the frost formed on the evaporator surfaces, which in turn further increases the energy consumption of the cooling device.
In a state of the art method, a heater wire is used, which is disposed preferably around the evaporator in order to melt the frost in the cooling device. According to this method, the cooling cycle is terminated after the formation of frost and the heater wire is energized to melt the frost. Due to the energizing of said heater wire, the energy consumption of the cooling device increases.
In the state of the Turkish Patent Document No. TR2017/19280, a cooling device is disclosed, wherein the frost formation on the evaporator is prevented, thus providing energy saving.
The aim of the present invention is the realization of a cooling device wherein the frost formation in the freezing compartment is prevented, thus decreasing the energy consumption.
The cooling device realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, wherein the frost formation in the freezing compartment is prevented, comprises at least one dehumidification apparatus which is placed into the freezing compartment and which comprises a body having at least one inlet opening, at least one outlet opening and at least one desiccant material which is placed between the inlet opening and the outlet opening and which dehumidifies the humid air entering through the inlet opening, thus enabling the dehumidified air to leave through the outlet opening. In the preferred embodiment of the present invention, the body is in the form of a box. By means of said dehumidification apparatus, the moisture in the humid air, wherein the moisture therein would turn into frost when the temperature thereof falls to a certain degree, is retained by the desiccant material and the dehumidified air is guided towards the evaporator. Thus, since there would be no moisture in the air as a result of the heat transfer on the evaporator, the air with decreased temperature does not cause any condensation or any frost formation in the freezing compartment.
In an embodiment of the present invention, the desiccant material is selected from a group comprising chemicals suitable for dehumidifying the air flowing through the body such as silica gel, anhydrous calcium chloride, sodium hydroxide, potassium hydroxide, etc.
In an embodiment of the present invention, the dehumidification apparatus in the cooling device comprises at least one cover which is provided on the body and which is configured to cover the inlet opening so as to allow the air to enter the body through the inlet opening when required. By covering the inlet opening by means of the cover, the air containing moisture under a certain level is prevented from entering the dehumidification apparatus, thus ensuring the effective use of the desiccant material.
In an embodiment of the present invention, the dehumidification apparatus in the cooling device comprises at least one drive element which enables the cover to move between at least one first position where the cover at least partially covers the inlet opening and at least one second position where the cover does not cover the inlet opening. Therefore, the cover is enabled to be automatically opened/closed without requiring any manual intervention to the cover from the outside.
In an embodiment of the present invention, the inlet opening and the cover on the dehumidification apparatus in the cooling device are integrated with each other. In the preferred embodiment of the present invention, the structure which comprises an inlet opening and the cover is a shutter. Thus, by producing the two components in an integrated manner, ease of production and assembly is provided.
In an embodiment of the present invention, the dehumidification apparatus comprises at least one guiding member which is arranged in the vicinity of the outlet opening and which enables the dehumidified air leaving the outlet opening to be directly guided to the evaporator. Thus, the dehumidified air is prevented from holding moisture again in the freezing compartment before being delivered to the evaporator, and the risk of condensation during the heat transfer on the evaporator is eliminated.
In an embodiment of the present invention, the cooling device comprises at least one heater which heats the desiccant material such that the moisture sucked and held by the desiccant material is discharged out of the desiccant material as water vapor. Consequently, when the desiccant material holds moisture up to a level so as to almost entirely prevent the desiccant material from holding moisture, the desiccant material is heated by the heater so as to release the moisture thereon, and thus, the desiccant material is regenerated without requiring the desiccant material to be changed with another desiccant material and the need for using a new desiccant material each time is eliminated.
In an embodiment of the present invention, the guiding member is configured to be automatically moved by the drive element so as to move between at least one first position where the dehumidified air is directly guided to the evaporator through the outlet opening, and at least one second position where the water vapor, which is formed after the heating and dehumidification of the desiccant material, is guided towards a water discharge channel arranged in the freezing compartment. Thus, by directly guiding the dehumidified air to the evaporator and by directly guiding the water vapor to the water discharge channel, the formation of condensation during the heat transfer on the evaporator and hence the formation of frost inside the freezing compartment is efficiently prevented.
In an embodiment of the present invention, the guiding member is preferably in the form of a wing. In the preferred embodiment of the present invention, the wing has a wide surface area for guiding the air and/or the water vapor. Thus, the dehumidified air and/or the water vapor is enabled to be efficiently directed to the evaporator and/or the water discharge channel over a wide surface.
In an embodiment of the present invention, the body extends so as to narrow from the inlet opening towards the outlet opening. Thus, by means of the body narrowing towards the outlet opening, the flow rate of the dehumidified air and/or of the water vapor leaving the body through the outlet opening is increased.
In an embodiment of the present invention, the cooling device comprises at least one first sensor which is disposed in the freezing compartment and which is configured to detect the humidity of the air inside the freezing compartment, and at least one control unit which is in communication with the first sensor and the drive element and which is configured to receive the data on the humidity of the air detected by the first sensor from the first sensor and to process said data, and upon deciding that the humidity value of the air in the freezing compartment is equal to or higher than a predetermined humidity value, to bring the cover to the position where the inlet opening is not closed and to bring the guiding member to the position where the dehumidified air is directed to the evaporator. Thus, the air in the freezing compartment is allowed to enter the dehumidification apparatus only when said air has a humidity value higher than a certain level, and said humid air is enabled to be dehumidified in the dehumidification apparatus to be directed to the evaporator.
In an embodiment of the present invention, the control unit is in communication with the fan in the freezing compartment, and is configured to send commands to the drive element to move the cover to the position where the inlet opening is not closed while operating the fan such that the air in the freezing compartment flows towards the inlet opening of the dehumidification apparatus. Thus, the fan starts operating with the command received from the control unit and forces the humid air in the freezing compartment to flow towards the inlet opening of the dehumidification apparatus. Consequently, the large amount of humid air which is forced towards the inlet opening by the fan is enabled to enter the dehumidification apparatus so as to be dehumidified by the desiccant material.
In an embodiment of the present invention, the cooling device comprises at least one second sensor which is disposed in the body and which is configured to determine the moisture level in the desiccant material. Thus, by determining the amount of moisture held by the desiccant material, it is known whether the desiccant material may hold further moisture.
In an embodiment of the present invention, the control unit is in communication with the second sensor and the heater, and is configured to receive data on the amount of moisture held by the desiccant material detected by the second sensor from the second sensor, and to process said data, and to send a command to the heater to heat the desiccant material upon deciding that the amount of moisture in the desiccant material is equal to or higher than a predetermined moisture amount value which prevents the desiccant material from holding further moisture. Thus, it is automatically detected that the amount of moisture held in the desiccant material has reached the maximum moisture level which can be held by the desiccant material, and then the desiccant material is heated by the heater, the moisture on the desiccant material is removed, and the desiccant material which is already present in the dehumidification apparatus is enabled to be used again without requiring to change the desiccant material with a new desiccant material. In this case, high costs which would arise due to constant changing of the desiccant material are prevented.
In an embodiment of the present invention, while sending a command to the heater for heating the desiccant material, the control unit is configured to send a command to the drive element such that the cover is moved to the position where the inlet opening is closed and that the guiding member is moved to the position where the water vapor arising from the heating of the desiccant material is guided towards the water discharge channel. Thus, while the heater heats the desiccant material the humid air is prevented from entering the body through the inlet opening and said humid air is prevented from being heated again such that the hot air is not delivered into the freezing compartment, thus preventing the temperature in the freezing compartment from increasing, and the water vapor arising from the heating of the desiccant material is enabled to be directed towards the water discharge channel without being supplied into the freezing compartment.
By means of the present invention, with a dehumidification apparatus which is disposed into the freezing compartment of a cooling device, the humid air in the freezing compartment entering the body through the inlet opening is dehumidified by a desiccant material provided in the body such that the dehumidified dry air is directed towards the evaporator through the outlet opening, preventing condensation during the heat transfer on the evaporator and hence preventing frost formation in the freezing compartment. Moreover, in an embodiment of the present invention, when the amount of moisture held by the desiccant material reaches the maximum amount of moisture which can be held by said material, the desiccant material is heated by a heater. Thus, the desiccant material is dehumidified, and without requiring to change the desiccant material with a new desiccant material, the desiccant material which is already present in the dehumidification apparatus can be used again. The water vapor arising from the heating of the desiccant material is directed to a water discharge channel arranged in the freezing compartment so as to be discharged from the freezing compartment via said channel.
The cooling device 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 the cooling device of the present invention.
Figure 2 - is the perspective view of the dehumidification apparatus in the cooling device of the present invention.
Figure 3 - is the perspective view of the dehumidification apparatus when the dehumidification apparatus is at a position where the dehumidified air is directed to the evaporator in the cooling device of the present invention.
The elements illustrated in the figures are numbered as follows:

Cooling device
Freezing compartment
Evaporator
Fan
Inlet opening
Outlet opening
Body
Dehumidification apparatus
Guiding member
Heater
First temperature sensor
Control unit

The cooling device (1) comprises at least one freezing compartment (2); at least one evaporator (3) which transfers heat with the air in the freezing compartment (2) so as to keep the freezing compartment (2) at the desired temperature; and at least one fan (4) which disperses the air, which is brought to the desired temperature by means of the evaporator (3), in the freezing compartment (2). In the cooling device (1), the foodstuffs to be frozen are placed into the freezing compartment (2). The evaporator (3) evaporates the refrigerant, which is circulated in the cooling circuit for keeping the interior of the cooling device (1) cold, and, during this process, enables the temperature of the air in the freezing compartment (2) to decrease. The air with decreased temperature is homogeneously dispersed into the freezing compartment (2) by means of the fan (4).
The cooling device (1) comprises at least one dehumidification apparatus (8) which is placed into the freezing compartment (2) and which comprises a body (7) having at least one inlet opening (5), at least one outlet opening (6) and at least one desiccant material (not shown in figures) which is placed between the inlet opening (5) and the outlet opening (6) and which dehumidifies the humid air entering through the inlet opening (5), thus enabling the dehumidified air to leave through the outlet opening (6). By means of the dehumidification apparatus (8), the moisture in the humid air which would cause frost in the freezing compartment (2) is drawn by the desiccant material from the air flowing from the inlet opening (5) towards the outlet opening (6), and the dehumidified air is delivered to the evaporator (3). Thus, since there would be no moisture in the air as a result of the heat transfer on the evaporator (3), condensation and resulting frost formation in the freezing compartment (2) is prevented.
In an embodiment of the present invention, the desiccant material is selected from a group comprising silica gel, anhydrous calcium chloride, sodium hydroxide, potassium hydroxide, etc.
In an embodiment of the present invention, the dehumidification apparatus (8) in the cooling device (1) comprises at least one cover (not shown in figures) which is provided on the body (7) and which is configured to cover the inlet opening (5) so as to be opened when required. Thus, the already dehumidified air or the air containing a very low amount of moisture is prevented from entering the dehumidification apparatus (8).
In an embodiment of the present invention, the dehumidification apparatus (8) in the cooling device (1) comprises at least one drive element (not shown in figures) which enables the cover to move between at least one first position where the cover at least partially covers the inlet opening (5) and at least one second position where the cover does not cover the inlet opening (5). Thus, the cover is enabled to be automatically moved.
In an embodiment of the present invention, the inlet opening (5) and the cover on the dehumidification apparatus (8) in the cooling device (1) are integrated with each other and preferably in the form of a shutter. By means of this embodiment of the present invention, the number of components used is decreased, thus providing ease of assembly.
In an embodiment of the present invention, the dehumidification apparatus (8) in the cooling device (1) comprises at least one guiding member (9) which is arranged in the vicinity of the outlet opening (6) and which enables the dehumidified air leaving the outlet opening (6) to be directly guided to the evaporator (3). Thus, the already dehumidified air is prevented from holding moisture again in the freezing compartment (2) before being delivered to the evaporator (3), and the risk of condensation during the heat transfer on the evaporator (3) is eliminated.
In an embodiment of the present invention, the cooling device (1) comprises at least one heater (10) which heats the desiccant material such that the moisture held by the desiccant material is discharged out of the desiccant material as water vapor. Consequently, when the desiccant material holds moisture up to a level so as to almost entirely prevent the desiccant material from holding moisture, the desiccant material is dehumidified without requiring the desiccant material to be changed with another desiccant material and the need for using a new desiccant material each time is eliminated, providing cost advantage.
In an embodiment of the present invention, the guiding member (9) is configured to be automatically driven by the drive element so as to move between at least one first position where the dehumidified air is directly guided to the evaporator (3) through the outlet opening (6), and at least one second position where the water vapor, which is formed after the dehumidification of the desiccant material, is guided towards a water discharge channel arranged in the freezing compartment (2). Thus, by directly guiding the dehumidified air to the evaporator (3) and by directly guiding the water vapor to the water discharge channel, the formation of condensation during the heat transfer on the evaporator (3) and hence the formation of frost inside the freezing compartment (2) is efficiently prevented.
In an embodiment of the present invention, the guiding member (9) is preferably in the form of a wing. Thus, the dehumidified air and/or the water vapor is enabled to be efficiently directed to the evaporator (3) and/or the water discharge channel over a wide surface.
In an embodiment of the present invention, the body (7) extends from the inlet opening (5) towards the outlet opening (6) such that the inner volume thereof decreases. Thus, by means of the body (7) narrowing towards the outlet opening (6), the flow rate of the dehumidified air and/or of the water vapor leaving through the outlet opening (6) is increased.
In an embodiment of the present invention, the cooling device (1) comprises at least one first sensor (11) which is disposed in the freezing compartment (2) and which is configured to detect the humidity of the air inside the freezing compartment (2), and at least one control unit (12) which is in communication with the first sensor (11) and the drive element and which is configured to receive the data on the humidity of the air detected by the first sensor (11) from the first sensor (11) and to process said data, and upon deciding that the humidity value of the air in the freezing compartment (2) is equal to or higher than a predetermined humidity value, to bring the cover to the position where the inlet opening (5) is not closed and to bring the guiding member (9) to the position where the dehumidified air is directed to the evaporator (3). Thus, the air in the freezing compartment (2) is allowed to enter the dehumidification apparatus (8) only when said air has a certain humidity value so as to be dehumidified and directed to the evaporator (3), ensuring the efficient use of the desiccant material.
In an embodiment of the present invention, the control unit (12) is in communication with the fan (4), and is configured to send commands to the drive element to move the cover to the position where the inlet opening (5) is not closed while operating the fan (4) such that the air in the freezing compartment (2) is directed towards the inlet opening (5) of the dehumidification apparatus (8). Thus, the humid air in the freezing compartment (2) is enabled to efficiently enter through the inlet opening (5) so as to be dehumidified.
In an embodiment of the present invention, the cooling device (1) further comprises at least one second sensor (not shown in figures) which is disposed in the body (7) and which is configured to detect the amount of moisture held by the desiccant material.
In an embodiment of the present invention, the control unit (12) is in communication with the second sensor and the heater (10), and is configured to receive data on the amount of moisture held by the desiccant material detected by the second sensor from the second sensor, and to process said data, and to send a command to the heater (10) to heat the desiccant material upon deciding that the amount of moisture in the desiccant material is equal to or higher than a predetermined moisture amount value which prevents the desiccant material from holding further moisture. Thus, it is automatically detected that the amount of moisture held in the desiccant material has reached the maximum moisture level which can be held by the desiccant material, and then the desiccant material is heated by the heater (10), the moisture on the desiccant material is removed, and the desiccant material is enabled to be used again. In this case, high costs which would arise due to constant changing of the desiccant material are prevented.
In an embodiment of the present invention, while sending a command to the heater (10) for heating the desiccant material, the control unit (12) is configured to send a command to the drive element such that the cover is moved to the position where the inlet opening (5) is closed and that the guiding member (9) is moved to the position where the water vapor arising from the heating of the desiccant material is guided towards the water discharge channel. Thus, while the heater (10) heats the desiccant material the humid air is prevented from entering the body (7) through the inlet opening (5) and the air to be delivered into the freezing compartment (2) is prevented from being heated such that the hot air is not delivered into the freezing compartment (2), and the water vapor arising from the heating of the desiccant material is enabled to be directed towards the water discharge channel without being supplied into the freezing compartment (2).
By means of the present invention, with a dehumidification apparatus (8) which is disposed into the freezing compartment (2), the humid air in the freezing compartment (2) entering the body (7) through the inlet opening (5) is dehumidified by a desiccant material provided in the body (7) such that the dehumidified air is directed towards the evaporator (3) through the outlet opening (6), preventing condensation during the heat transfer on the evaporator (3) and hence preventing frost formation in the freezing compartment (2). Moreover, in an embodiment of the present invention, when the amount of moisture held by the desiccant material reaches the maximum amount of moisture which can be held by said material, the desiccant material is heated by a heater (10) so as to be dehumidified and made ready to be used again without requiring any replacement, and the water vapor arising from the heating is discharged from the freezing compartment (2) through a water discharge channel arranged in the freezing compartment (2).

Claims

A cooling device (1) comprising at least one freezing compartment (2); at least one evaporator (3) which transfers heat with the air in the freezing compartment (2) so as to keep the freezing compartment (2) at the desired temperature; and at least one fan (4) which disperses the air, which is brought to the desired temperature by means of the evaporator (3), in the freezing compartment (2), characterized by at least one dehumidification apparatus (8) which is placed into the freezing compartment (2) and which comprises a body (7) having at least one inlet opening (5), at least one outlet opening (6) and at least one desiccant material which is placed between the inlet opening (5) and the outlet opening (6) and which dehumidifies the humid air entering through the inlet opening (5), thus enabling the dehumidified air to leave through the outlet opening (6).
A cooling device (1) as in Claim 1, characterized by the desiccant material which is selected from a group comprising silica gel, anhydrous calcium chloride, sodium hydroxide, potassium hydroxide, etc.
A cooling device (1) as in Claim 1 or 2, characterized by the dehumidification apparatus (8) comprising at least one cover which is provided on the body (7) and which is configured to cover the inlet opening (5) so as to be opened when required.
A cooling device (1) as in Claim 3, characterized by the dehumidification apparatus (8) comprising at least one drive element which enables the cover to move between at least one first position where the cover at least partially covers the inlet opening (5) and at least one second position where the cover does not cover the inlet opening (5).
A cooling device (1) as in Claim 3 or 4, characterized by the inlet opening (5) and the cover which are integrated to each other.
A cooling device (1) as in any one of the above claims, characterized by the dehumidification apparatus (8) comprising at least one guiding member (9) which is arranged in the vicinity of the outlet opening (6) and which enables the dehumidified air leaving the outlet opening (6) to be directly guided to the evaporator (3).
A cooling device (1) as in any one of the above claims, characterized by at least one heater (10) which heats the desiccant material such that the moisture held by the desiccant material is discharged out of the desiccant material as water vapor.
A cooling device (1) as in Claim 6 or 7, characterized by the guiding member (9) which is configured to be automatically driven by the drive element so as to move between at least one first position where the dehumidified air is directly guided to the evaporator (3) through the outlet opening (6), and at least one second position where the water vapor, which is formed after the dehumidification of the desiccant material, is guided towards a water discharge channel arranged in the freezing compartment (2).
A cooling device (1) as in any one of the Claims 6 to 8, characterized by the guiding member (9) which is in the form of a wing.
A cooling device (1) as in any one of the above claims, characterized by the body (7) which extends such the inner volume thereof decreases from the inlet opening (5) towards the outlet opening (6).
A cooling device (1) as in any one of the Claims 6 to 10, characterized by at least one first sensor (11) which is disposed in the freezing compartment (2) and which is configured to detect the humidity of the air inside the freezing compartment (2), and at least one control unit (12) which is in communication with the first sensor (11) and the drive element and which is configured to receive the data on the humidity of the air detected by the first sensor (11) from the first sensor (11) and to process said data, and upon deciding that the humidity value of the air in the freezing compartment (2) is equal to or higher than a predetermined humidity value, to bring the cover to the position where the inlet opening (5) is not closed and to bring the guiding member (9) to the position where the dehumidified air is directed to the evaporator (3).
A cooling device (1) as in Claim 11, characterized by the control unit (12) which is in communication with the fan (4), and which is configured to send commands to the drive element to move the cover to the position where the inlet opening (5) is not closed while operating the fan (4) such that the air in the freezing compartment (2) is directed towards the inlet opening (5) of the dehumidification apparatus (8).
A cooling device (1) as in any one of the above claims, characterized by at least one second sensor which is disposed in the body (7) and which is configured to detect the amount of moisture held by the desiccant material.
A cooling device (1) as in Claim 13, characterized by the control unit (12) which is in communication with the second sensor and the heater (10), and which is configured to receive data on the amount of moisture held by the desiccant material detected by the second sensor from the second sensor, and to process said data, and to send a command to the heater (10) to heat the desiccant material upon deciding that the amount of moisture in the desiccant material is equal to or higher than a predetermined moisture amount value which prevents the desiccant material from holding further moisture.
A cooling device (1) as in Claim 14, characterized by the control unit (12) which, while sending a command to the heater (10) for heating the desiccant material, is configured to send a command to the drive element such that the cover is moved to the position where the inlet opening (5) is closed and that the guiding member (9) is moved to the position where the water vapor arising from the heating of the desiccant material is guided towards the water discharge channel.