WO2016050435A1

WO2016050435A1 - A cooling device comprising a humidity-controlled crisper

Info

Publication number: WO2016050435A1
Application number: PCT/EP2015/069991
Authority: WO
Inventors: Isil USLU; Serdar Kocaturk; Feyzi Alper SOYSAL; Levent Akdag
Original assignee: Arcelik Anonim Sirketi
Priority date: 2014-10-02
Filing date: 2015-09-02
Publication date: 2016-04-07

Abstract

The present invention relates to a cooling device (1) comprising a body (2) wherein foods and beverages are placed; a lower crisper (3) that is placed in the body (2) and that has a (T1) temperature; an upper crisper (4) that is disposed on the lower crisper (3) and that has a (T2) temperature that is higher than the (T1) temperature; an air duct (5) that provides the air transfer to the lower crisper (3); at least one air inlet (6) that provides cold air passage into the air duct (5); a valve (7) that provides the opening/closing of the air duct (5) and a control unit (8) that enables the opening/closing of the valve (7).

Description

A COOLING DEVICE COMPRISING A HUMIDITY-CONTROLLED CRISPER

The present invention relates to a cooling device comprising a crisper wherein humidity level is controlled.

Cooling devices comprise a cooling compartment wherein foods and beverages are stored, a freezer compartment that enables foods to be stored by being frozen, and a crisper that is disposed in the cooling compartment and wherein foods such as vegetables and fruits are stored. Cooling the crisper is provided by means of partially directing the cold air in other compartments into the crisper. When the foods inside the crisper directly contact the cold and dry air, the relative humidity rate in the crisper remains below the optimum storage conditions, and hence the foods wither by losing moisture and spoil in a shorter period of time. In order to prevent the foods placed in the crisper from losing humidity and dehydrating, the air flow between the crisper and the fresh food compartment is enabled to remain at a limited level. In this case, a temperature difference, although small, occurs between the crisper and the fresh food compartment interior volume. Depending on the high relative humidity rate and the temperature difference, condensation occurs on the surfaces that separate the fresh food compartment interior volume and the crisper. The condensation occurring on the surfaces of the crisper results in dripping of water on the foods stored in the crisper and this causes the foods to spoil by adversely affecting storage lives of the foods. In order to store the foods without being spoiled for a long time, the appropriate humidity rate must be provided and the condensation must be prevented from occurring on the crisper surfaces. As a result of performed experimental studies, it is known that the optimum storage condition for the fruits and vegetables placed in the crisper is a relative humidity rate of 90% and a temperature between 2 and 10 C degrees. The temperature value varies depending on the type of the food. Depending on the storage temperature, the vegetables spoil differently. Thus, it is required to group the vegetables by storage temperature and store them in different compartments.

Various methods have been developed in the state of the art for sending the cold air into the crisper in a controlled manner and preventing condensation from occurring by adjusting the humidity balance in the crisper.

In the state of the art European Patent Application No. EP1936302, a cooling device is disclosed, that has a crisper wherein moisture control is performed by controlling the air intake and exit.

In the state of the art Japanese Patent Application No. JP2011043266, a cooling device is disclosed, wherein the transpiration rate of the foods is kept within a certain range according to the temperature data obtained by measuring the ambient and food surface temperatures.

The aim of the present invention is the realization of a cooling device wherein the storage lives of the foods are prolonged by preventing the humidity loss in two crispers at different temperatures and by controlling the condensation.

The cooling device realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a lower crisper wherein the foods required to be kept at lower temperatures are placed, an upper crisper that is positioned so as to be above the lower crisper and wherein the foods required to be kept at higher temperatures are placed, an air duct that provides the delivery of the cool air into the lower crisper, an air inlet that provides the passage of the air into the air duct and a valve that is disposed on the air inlet and that is controlled by a control unit for the opening/closing thereof.

The cooling device of the present invention comprises a hole that enables the condensation in the upper crisper to be discharged to the air duct, thus to be removed from the upper crisper and further the air duct that is disposed between the lower crisper and the upper crisper and that enables the said discharged condensation to be mixed with the cool and dry air received from the air inlet and to be delivered to the lower crisper for cooling and moisturizing purposes. The condensation occurring in the upper crisper, particularly on the crisper surfaces is collected at the upper crisper base with the effect of the gravity without contacting the foods and then discharged to the air duct. Thus, the foods stored in the upper crisper are prevented from spoiling by contacting the water drops collected due to condensation. Moreover, by means of the humid cool air delivered to the lower crisper, the foods stored in the lower crisper are prevented from losing humidity and from withering. The cool and dry air received into the air duct does not rise since it is cool while moving at a flow rate below 0.1 m/s along the air duct, thus the said air is sent to the lower crisper after sweeping the condensation in the air duct without entering the upper crisper.

In an embodiment of the present invention, the control unit controls the opening/closing of the valve according to the data received from a relative humidity rate sensor disposed inside the upper crisper. The control unit, opening the valve upon deciding that the condensation has occurred according to the data received from the sensors, mixes the condensation accumulated in the air duct with the cool air and sends it to the lower crisper for moisturizing purposes. In cases wherein there is no condensation, no condensation accumulates in the air duct, thereby the control unit closes the valve and prevents the cool and dry air received only from the air inlet from being sent to the lower crisper.

In another embodiment of the present invention, the control unit comprises controls the opening/closing of the valve according to the data received from a first temperature sensor disposed inside the lower crisper and from a second temperature sensor disposed inside the upper crisper. The control unit, opening the valve upon deciding that the condensation has occurred according to the data received from the sensors, closes the valve if there is no condensation.

In another embodiment of the present invention, the control unit opens the valve if the relative humidity value (RH) measured by the relative humidity sensor is above the maximum relative humidity rate (RHmax) determined by the manufacturer, closes the valve if the measured relative humidity rate (RH) is below the minimum relative humidity rate (RHmin) determined by the manufacturer and controls the opening/closing of the valve according to the data received from the first temperature sensor and the second temperature sensor if the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin). If the measured relative humidity rate (RH) is above the maximum relative humidity rate (RHmax), it is decided that condensation has accumulated in the air duct and thus the valve is opened and the accumulated condensation is enabled to mixed with the cool air and to be send to the lower crisper. When the measured relative humidity rate (RH) falls below the minimum relative humidity rate (RHmin), it is decided that the condensation has ended and the valve is closed.

In another embodiment of the present invention, the control unit calculates the temperature difference (∆T) between the lower crisper and the upper crisper according to the data received from the temperature sensors disposed in the lower crisper and the upper crisper if the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin), opens the valve upon deciding that condensation has occurred in the upper limit if the calculated temperature difference (∆T) is above the maximum temperature difference (∆Tmax) determined by the manufacturer, closes the valve upon deciding that there is no condensation in the upper crisper if the calculated temperature difference (∆T) is below the minimum temperature difference (∆Tmin) determined by the manufacturer and controls the opening/closing of the valve according to a function determined by the manufacturer of the measured relative humidity rate (RH) and the calculated temperature difference (∆T) if the calculated temperature difference (∆T) is between the maximum temperature difference (∆Tmax) and the minimum temperature difference (∆Tmin).

In another embodiment of the present invention, the control unit opens the valve if the ratio of the measured relative humidity rate (RH) to the calculated temperature difference (∆T) is below the limit humidity rate (RHt) determined by the manufacturer, and closes the valve if the ratio is above the limit humidity rate (RHt).

By means of the present invention, in a cooling device having a two-tier crisper configuration, the storage lives of the foods are prolonged by means of the humidity exchange between the lower crisper and the upper crisper.

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 cross-sectional schematic view of the refrigerator in an embodiment of the present invention.

Figure 2 – is the sideways cross-sectional schematic view of the refrigerator in an embodiment of the present invention.

The elements illustrated in the figures are numbered as follows:

Cooling device
Body
Lower crisper
Upper crisper
Air duct
Air inlet
Valve
Control unit
Hole
Relative humidity sensor
First temperature sensor
Second temperature sensor

The cooling device (1) comprises a body (2) wherein foods and beverages are placed; a lower crisper (3) that is placed in the body (2) and that has a (T1) temperature; an upper crisper (4) that is disposed on the lower crisper (3) and that has a (T2) temperature that is higher than the (T1) temperature; an air duct (5) that provides the air transfer to the lower crisper (3); at least one air inlet (6) that provides cold air passage into the air duct (5); a valve (7) that provides the opening/closing of the air duct (5) and a control unit (8) that enables the opening/closing of the valve (7).

The cooling device (1) of the present invention comprises at least one hole (9) that is arranged on the base of the upper crisper (4) and that enables the condensation occurring in the upper crisper (4) to be discharged to the air duct (5). The air duct (5) is disposed between the lower crisper (3) and the upper crisper (4) and mixes the condensation discharged from the upper crisper (4) through the holes (9) with the cool air and delivers the mixture to the lower crisper (3). In this embodiment, the foods required to be stored at low temperatures are placed into the lower crisper (3) kept at the (T1) temperature and the foods required to be stored at higher temperatures are placed into the upper crisper (4) that is positioned so as to be above the lower crisper (3) and that is kept at the (T2) temperature that is higher than (T1). The condensation occurring in the upper crisper (4) due to the temperature difference between the upper crisper (4) and the lower crisper (3) is accumulated at the base of the upper crisper (4) and flows into the air duct (5) after passing through the hole (9). The cool and dry air received into the air duct (5) from the air inlet (6) is send to the lower crisper (3) after being mixed with the condensation discharged from the upper crisper (4) and moisturized. Thus, the humidity is removed by discharging the condensation in the upper crisper (4) while the lower crisper (3) is enabled to be moisturized. Thus, the foods stored in the upper crisper (4) are prevented from being spoiled due to condensation and the foods stored in the lower crisper (3) are prevented from being spoiled due to humidity loss, thus the storage lives of the foods are prolonged.

In an embodiment of the present invention, the cooling device (1) comprises a relative humidity sensor (10) disposed in the upper crisper (4), a first temperature sensor (11) that is disposed in the lower crisper (3), a second temperature sensor (12) that is disposed in the upper crisper (4) and a control unit (8) that controls the opening/closing of the valve (7) according to the data received from the relative humidity sensor (10) and/or from the first temperature sensor (11) and the second temperature sensor (12). Upon deciding that condensation has occurred in the upper crisper (4) according to the data received, the control unit (8) opens the valve (7) to enable the air entry into the air duct (5), thus the condensation accumulating in the air duct (5) is swept and the air is moisturized and directed towards the lower crisper (3). In cases wherein there is no condensation in the upper crisper (4), humidity loss is prevented by closing the valve (7) and sending only the cool and dry air into the lower crisper (3).

In an embodiment of the present invention, the cooling device (1) comprises a first temperature sensor (11) that is disposed in the lower crisper (3), a second temperature sensor (12) that is disposed in the upper crisper (4) and a control unit (8) that controls the opening/closing of the valve (7) according to the data received from the first temperature sensor (11) and the second temperature sensor (12). The control unit (8) determines if there is condensation in the upper crisper (4) according to the data received, opens the valve (7) to enable the air entry into the air duct (5) if there is condensation and closes the valve (7) to prevent the air entry into the air duct (5) if there is not condensation.

In another embodiment of the present invention, the control unit (8) opens the valve (7) if the relative humidity value (RH) measured by the relative humidity sensor (10) is above the maximum relative humidity rate (RHmax) determined by the manufacturer, closes the valve (7) if the measured relative humidity rate (RH) is below the minimum relative humidity rate (RHmin) determined by the manufacturer and controls the opening/closing of the valve (7) according to the data received from the first temperature sensor (11) and the second temperature sensor (12) if the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin). If the relative humidity rate (RH) inside the upper crisper (4) is above the maximum relative humidity rate (RHmax), the control unit (8) decides that there is condensation in the upper crisper (4) and opens the valve (7). The condensation occurring in the upper crisper (4) is mixed with the cool and dry air in the air duct (5) and sent to the lower crisper (3). If the relative humidity rate (RH) inside the upper crisper (4) is below the minimum relative humidity rate (RHmin), the control unit (8) decides that there is no condensation in the upper crisper (4) and closes the valve (7). In cases wherein there is no condensation in the air duct (5), humidity loss in the lower crisper (3) is inhibited by preventing the delivery of the cool and dry air received into the air duct (5) directly into the lower crisper (3). If the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin), it is not sufficient to evaluate only the relative humidity rate (RH) in order to determine if there is condensation in the upper crisper (4). For an accurate evaluation, the control unit (8) uses the data received from the first temperature sensor (11) and from the second temperature sensor (12).

In another embodiment of the present invention, the control unit (8) calculates the temperature difference (∆T) between the lower crisper (3) and the upper crisper (4) according to the temperature value (T1) measured by the first temperature sensor (11) and to the temperature value (T2) measured by the second temperature sensor (12), opens the valve (7) if the calculated temperature difference (∆T) is above the maximum temperature difference (∆Tmax) determined by the manufacturer, closes the valve (7) if the calculated temperature difference (∆T) is below the minimum temperature difference (∆Tmin) determined by the manufacturer and controls the opening/closing of the valve (7) according to a function of the measured relative humidity rate (RH) and the calculated temperature difference (∆T) if the calculated temperature difference (∆T) is between the maximum temperature difference (∆Tmax) and the minimum temperature difference (∆Tmin). If the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin), the control unit (8) evaluates the measured temperature difference (∆T) between the upper crisper (4) and the lower crisper (3) and determines determine if there is condensation in the upper crisper (4). If the measured temperature difference (∆T) is above the maximum temperature difference (∆Tmax), condensation occurs in the upper crisper (4) that is kept at higher temperatures, thus if this is the case, the control unit (8) opens the valve (7). If the measured temperature difference (∆T) is below the minimum temperature difference (∆Tmin), it is decided that the measured temperature difference (∆T) is not sufficient to cause condensation, thus the valve (7) is closed. If the measured temperature difference (∆T) is between the maximum temperature difference (∆Tmax) and the minimum temperature difference (∆Tmin), the decision on the formation of condensation is taken according to a function determined by the manufacturer, wherein the measured relative humidity rate (RH) and the calculated temperature difference (∆T) are evaluated.

In another embodiment of the present invention, the control unit (8) opens the valve if the ratio of the measured relative humidity rate (RH) to the calculated temperature difference (∆T) is below the limit humidity rate (RHt) determined by the manufacturer, and closes the valve (7) if the ratio is above or equal to the limit humidity rate (RHt).

In the cooling device (1) of the present invention, by means of the air flow between the lower crisper (3) and the upper crisper (4) wherein foods are stored at different temperatures, the condensation occurring in the upper crisper (4) is taken into the air duct (5) and here mixed with the cool and dry air to be delivered into the lower crisper (3) for moisturizing purposes. Thus, the foods are prevented from being spoiled due to the condensation occurring in the upper crisper (4) and due to the humidity loss in the lower crisper (3), thus the foods stored in both crispers (3, 4) are enabled to be preserved for a longer time.

Claims

A cooling device (1) comprising a body (2) wherein foods and beverages are placed; a lower crisper (3) that is placed in the body (2) and that has a (T1) temperature; an upper crisper (4) that is disposed on the lower crisper (3) and that has a (T2) temperature that is higher than the (T1) temperature; an air duct (5) that provides the air transfer to the lower crisper (3); at least one air inlet (6) that provides cold air passage into the air duct (5); a valve (7) that provides the opening/closing of the air duct (5) and a control unit (8) that enables the opening/closing of the valve (7), characterized by

- at least one hole (9) that is arranged on the base of the upper crisper (4) and that enables the condensation occurring in the upper crisper (4) to be discharged to the air duct (5) and

- the air duct (5) that is disposed between the lower crisper (3) and the upper crisper (4) and that mixes the condensation discharged from the upper crisper (4) with the cool air and delivers the mixture to the lower crisper (3).
A cooling device (1) as in Claim 1, characterized by a relative humidity sensor (10) that is disposed in the upper crisper (4) and the control unit (8) that controls the opening/closing of the valve (7) according to the data received from the relative humidity sensor (10).
A cooling device (1) as in Claim 2, characterized by a first temperature sensor (11) that is disposed in the lower crisper (3), a second temperature sensor (12) that is disposed in the upper crisper (4) and a control unit (8) that controls the opening/closing of the valve (7) according to the data received from the first temperature sensor (11) and the second temperature sensor (12).
A cooling device (1) as in Claim 2 or 3, characterized by the control unit (8) that opens the valve (7) if the relative humidity value (RH) measured by the relative humidity sensor (10) is above the maximum relative humidity rate (RHmax) determined by the manufacturer, that closes the valve (7) if the measured relative humidity rate (RH) is below the minimum relative humidity rate (RHmin) determined by the manufacturer and that controls the opening/closing of the valve (7) according to the data received from the first temperature sensor (11) and the second temperature sensor (12) if the measured relative humidity rate (RH) is between the maximum relative humidity rate (RHmax) and the minimum relative humidity rate (RHmin).
A cooling device (1) as in Claim 4, characterized by the control unit (8) that calculates the temperature difference (∆T) between the lower crisper (3) and the upper crisper (4) according to the temperature value (T1) measured by the first temperature sensor (11) and to the temperature value (T2) measured by the second temperature sensor (12), that opens the valve (7) if the calculated temperature difference (∆T) is above the maximum temperature difference (∆Tmax) determined by the manufacturer, that closes the valve (7) if the calculated temperature difference (∆T) is below the minimum temperature difference (∆Tmin) determined by the manufacturer and that controls the opening/closing of the valve (7) according to a function of the measured relative humidity rate (RH) and the calculated temperature difference (∆T) if the calculated temperature difference (∆T) is between the maximum temperature difference (∆Tmax) and the minimum temperature difference (∆Tmin).
A cooling device (1) as in Claim 5, characterized by the control unit (8) that opens the valve if the ratio of the measured relative humidity rate (RH) to the calculated temperature difference (∆T) is below the limit humidity rate (RHt) determined by the manufacturer, and that closes the valve (7) if the ratio is above or equal to the limit humidity rate (RHt).