WO2018033397A1

WO2018033397A1 - A cooling device comprising a clear ice making mechanism

Info

Publication number: WO2018033397A1
Application number: PCT/EP2017/069597
Authority: WO
Inventors: Mert PATKAVAK; Mert Can TASKIN; Erkan KARAKAYA; Sabahattin Hocaoglu; Umutcan Salih ERYILMAZ
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2016-08-18
Filing date: 2017-08-03
Publication date: 2018-02-22
Anticipated expiration: 2019-02-18
Also published as: TR201611669A2

Abstract

A cooling device, in particular a refrigerator, comprising a thermally-insulated cabin (1) and a clear ice making mechanism (10) that is provided in the cabin (1) and that comprises an ice tray (40) vertically arranged such that the water supplied by a water distributor (20) disposed thereabove passes through a plurality of successive partitions (44) thereon so as to flow longitudinally, a heating element (60) that is positioned close to the ice tray (40) and a metallic element (30) that expands when the heating element (60) is activated and changes its form in the ice tray (40) so as to separate the ice cube formed in the partition (44) from the partition (44).

Description

A COOLING DEVICE COMPRISING A CLEAR ICE MAKING MECHANISM

The present invention relates to cooling devices, in particular refrigerators, wherein ice is produced for making ice cubes by means of water flow over a vertical tray.

In the fresh food compartment or in a separate ice making device in the thermally-insulated body of the cooling devices, clear ice pieces are produced by flowing water over a vertical metal mold connected to an evaporator and by cooling the metal surface. Clear ice pieces can be obtained by removing the air dissolving in the water and cleansing the water of foreign materials such as dust, chlorine, some minerals, etc. as much as possible during or before freezing the water. The ice obtained has a clear and aesthetic appearance to the extent that the air content in the crystallized ice is removed. The ice crystallizing while freezing transfers the air therein to the water. During the formation of ice, the air dissolving in the water accumulates in the remaining water and particularly in the thin layer just above the freezing surface. If the concentration of the dissolved air exceeds a certain value, bubble formation occurs. A large number of small bubbles are formed during quick freezing and the obtained ice has a foggy appearance.

It is possible to produce clear ice pieces by decreasing the freezing speed and thus removing the air in the water by diffusion. However, this process requires very long periods of time such as 6 to 10 hours. In order to obtain clear ice pieces in shorter periods of time, the water at the freezing surface must be in constant flow. This method is called fractional freezing method. The dissolved air separated from the ice when the water being frozen is not stagnant but flows is carried with the water and does not accumulate on the ice. Thus, bubble formation is prevented. In the devices producing clear ice by means of the fractional freezing method, various methods are used to decide whether sufficient amount of ice is produced and to terminate the ice making process. When ice production process is completed, a discharge mechanism is activated and the ice tray is enabled to be emptied.

The Patent Publication No. US4947653A discloses an ice maker including freeze and harvest controls. The evaporator includes a unitary evaporator and ice mold. A compressor and condenser cool the evaporator to freeze ice on the mold in a normal refrigeration cycle and the mold is defrosted by hot gas to harvest ice from the ice mold. The temperature of the ice mold and the liquid line temperature of the condenser are sensed to control the length of time of the ice forming cycle. The harvest cycle includes a defrost period followed by a delay period. To initiate the harvest cycle, logic control actuates the hot gas solenoid control. Solenoid connects the evaporator to the compressor discharge line to supply superheated refrigerant gas to heat the evaporator and its associated ice forming molds. Thus, ice formed during the freeze cycle will slide out of the ice forming molds.

The aim of the present invention is to decrease the energy required for the ice cube harvest cycle in the clear ice production.

The present invention realized in order to attain the said aim is a cooling device, in particular a refrigerator, comprising a thermally-insulated cabin and a clear ice making mechanism that is provided in the cabin and that comprises an ice tray vertically arranged such that the water supplied by a water distributor disposed thereabove passes through a plurality of successive partitions thereon so as to flow longitudinally. A preferred embodiment of the present invention comprises a heating element positioned close to the ice tray and a metallic element that expands when the heating element is activated and changes its form in the ice tray so as to separate the ice cube formed in the partition from the partition. The metallic element expands and changes form with the thermal energy received from the heating element, for example displaces, and thus enabling the ice cube to be separated from the ice tray. Thus, the need for heating the ice tray to melt the ice in the ice harvest cycle is eliminated and the ice cubes are discharged by being pushed by force.

In a preferred embodiment of the present invention, the metallic element is fixed on the inside of the partition so as to bend outwards by displacing when heated. Thus, the metallic element not only separates the ice cube from the partition but also enables the ice cube to be pushed out of the partition. In an alternative embodiment, the metallic element can be placed on the ice tray so as to deform the ice tray to displace the ice cubes.

In a preferred embodiment of the present invention, the metallic element is provided at the base of the partition so as to contact the ice cube. In this case, the displacement occurring due to expansion can be used to efficiently discharge the ice cube by being pushed from the base. In alternative embodiments, the metallic element can be placed into the partition so as to cover not only the base, but also one of the adjacent side walls or all the surfaces.

In a preferred embodiment of the present invention, in an ice harvest mode, the heating power of the heating element is configured to provide such a heat on the metallic element to increase the displacement of the metallic element between 0.01 mm and 1 mm. This amount is sufficient to separate the ice cube from a tray that is used to achieve the dimensions of an ice cube used in a household.

In a preferred embodiment of the present invention, the heating element is adjacent to a rear wall of the ice tray. By positioning the heating element at the rear wall of the tray, the metallic element is enabled to be heated so as to expand without melting the ice cubes.

In a preferred embodiment of the present invention, a bottom wall of the partition is formed with a downward inclination such that the ice cube falls out of the partition by its own weight when pushed by the metallic element. The metallic element not only separates the ice cube from the partition, but also triggers the same to fall out of the ice tray by its own weight.

In a preferred embodiment of the present invention, the heating element comprises an electrical resistance. By providing electricity when the ice harvest cycle is started by connecting the electrical resistance for example to an electronic control unit of the refrigerator, the metallic element is enabled to expand so as to separate the ice cubes from the partitions and the ice cubes are harvested from the ice tray and collected in an ice receptacle. The electrical resistance is deactivated after supplying a thermal energy to enable the ice cubes to be separated from the partitions.

In a preferred embodiment of the present invention, the ice tray is produced from metal. Thus, when the heating element heats any region on the ice tray, the heat radiates over the entire ice tray by heat conduction and the metallic elements in all the partitions can be expanded.

In a preferred embodiment of the present invention, the metallic element comprises a bimetallic strip or shape memory alloy. These materials provide an efficient displacement with a small amount of thermal energy, thus decreasing the thermal energy required for the ice harvest cycle.

A cooling device realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

Figure 1 - is the perspective view of a refrigerator cabin comprising the clear ice making mechanism of the present invention.

Figure 2 - is the perspective view of a representative embodiment of the clear ice making mechanism.

Figure 3 - is the top view of an ice tray comprising shape memory metallic component.

Figure 4 - is the transversal cross-section view of the ice tray in Figure 3 in the heated state.

The elements illustrated in the figures are numbered as follows:

1 Cabin

2 Upper compartment

3 Lower compartment

4 Ice drawer

5 Evaporator

10 Clear ice making mechanism

20 Water distributor

22 Inlet

24 Receptacle

26 Front plate

30 Metallic element

32 Rear part

34 Front part

40 Ice tray

41 Front wall

44 Partition

45 Base

46 Water distribution part

47 Intermediate wall

48 Rear wall

49 Bottom wall

50 Water tank

52 Top opening

60 Heating element

62 Tube

Figure 1 shows the front perspective view of a thermally-insulated cabin (1) of a refrigerator comprising a clear ice making mechanism (10). The cabin (1) is divided into two adjacent compartments, namely an upper compartment (2) and a lower compartment (3). In the lower compartment (3), a water tank (50) extends over an ice drawer (4) in a detachable manner along the depth of the lower compartment (3). The water tank (50) has an upper opening (52) and an ice tray (40) vertically positioned in the lower compartment (3) is aligned over the upper opening (52) of the water tank (50). On the ice tray (40), partitions (44) suitable for ice cube production are arranged in the form of a matrix. The clear ice making mechanism (10) comprises a water distributor (20) at the upper part thereof. The water distributor (20) supplies water at a low flow rate onto the ice tray (40) through the outlets arranged at the lower part thereof. Thus, a film-like water flow constantly passes over the partitions (44). Behind the ice tray (40) of the clear ice making mechanism (10), an evaporator (5) bears against the ice tray (40) so as to provide heat transfer. The ice tray (40) is produced from metal. Thus, the water flowing over the partitions (44) efficiently cooled by the evaporator (5) by means of heat conduction starts to form ice mass.

Figure 2 shows a representative embodiment of the box-like clear ice making mechanism (10) used in the cooling device of the present invention. A plastic water distributor (20) is disposed at the upper part of the clear ice making mechanism (10). The water distributor (20) comprises a receptacle (24) wherein the water supplied through an inlet (22) connected to a water container (not shown in the figures) is transferred. The receptacle (24) transversely extends. A front plate (26) is disposed on the front part (34) of the receptacle (24). A cavity extends inwards from the lower side of the front plate (26) and along the lower side of the cavity an inclined planar water distribution part (46) extends on the upper surface of the ice tray (40). The planar front wall (41) of the ice tray (40) extends in an inclined and perpendicular manner towards the water tank (50). Partitions (44) arranged in the form of a matrix opening at the front wall (41) of the ice tray (40) are separated from each other by means of an adjacent intermediate wall (47). Each partition (44) is in the form of a cavity suitable for producing an ice cube. The partitions (44) comprise a planar base (45) and side walls rising from the base (45). The lowermost one of the side walls is a downward inclined lower wall (49). An evaporator (5) is disposed in the vicinity of a rear wall (48) of the ice tray (40). The evaporator (5) is connected to the refrigeration cycle (not shown in the figures) of the refrigerator.

Figure 3 shows the top view of an alternative ice tray (40). A metallic element (30) is fixed onto the base (45) so as to face outside from the front part (34) thereof. As shown in the cross-sectional view in Figure 4, the metallic element (30) is in the form of a short bimetallic strip having a planar rear part (32) and seated onto the base (45). The size of the metallic element (30) is configured so as to fit onto the base (45) in the normal position when not heated. Thus, when the metallic element (30) is heated, as shown in Figure 4, the front part (34) expands and takes a convex shape and pushes the ice cube in the partition (44) in the axial direction. The heating process is performed by means of a heating element (60). The heating element (60) is an electrical resistance in tube (62) form and disposed on the rear wall (48) in serpentine form. Cavities are formed on the rear wall (48) of the ice tray (40) so as to receive the tube (62) form.

In order to produce clear ice, the refrigerator delivers water from the water distributor (20) to the water distribution part (46). The water distribution part (46) enables the water to spread and flow in the form of a film over the front wall (41) of the ice tray (40). While the water passes through the partitions (44), ice formation occurs on the surface that the flowing water contacts since the evaporator (5) is active. By means of the constant flow of the water and the recirculation thereof from the water tank (50) to the water distributor (20), the partitions (44) collect ice and create a clear ice cube. Subsequently, the ice harvest cycle is started and the heating element (60) is operated by supplying electricity. The rear wall (48) of the metallic ice tray (40) transfers the heat to the metallic element (30) disposed on the base (45). The metallic element (30) is squeezed along its circumferential edges at the base (45) and bends outwards. Thus, the metallic element (30) contacts the ice cube from behind and pushed the same out of the partition (44) and separates the partition (44) and the ice cube from each other. The ice cube slides over the downward inclined bottom wall (49) due to its weight so as to be taken into the ice drawer (4). Since a similar structure is disposed in all the partitions (44), all the ice cubes in the partitions (44) can be discharged with the same mechanical system.

Claims

A cooling device, in particular a refrigerator, comprising a thermally-insulated cabin (1) and a clear ice making mechanism (10) that is provided in the cabin (1) and that comprises an ice tray (40) vertically arranged such that the water supplied by a water distributor (20) disposed thereabove passes through a plurality of successive partitions (44) thereon so as to flow longitudinally, characterized by a heating element (60) that is positioned close to the ice tray (40) and a metallic element (30) that expands when the heating element (60) is activated and changes its form in the ice tray (40) so as to separate the ice cube formed in the partition (44) from the partition (44).
A cooling device as in Claim 1, wherein the metallic element (30) is fixed on the inside of the partition (44) so as to bend outwards by displacing when heated.
A cooling device as in Claim 2, wherein the metallic element (30) is provided at the base (45) of the partition (44) so as to contact the ice cube.
A cooling device as in any one of the above claims, wherein in an ice harvest mode, the heating power of the heating element (6) is configured to provide such a heat on the metallic element (30) to increase the displacement of the metallic element (30) between 0.01 mm and 1 mm.
A cooling device as in any one of the above claims, wherein the heating element (60) is adjacent to a rear wall (48) of the ice tray (40).
A cooling device as in any one of the above claims, wherein a bottom wall (49) of the partition (44) is formed with a downward inclination such that the ice cube falls out of the partition (44) by its own weight when pushed by the metallic element (30).
A cooling device as in any one of the above claims, wherein the heating element (60) comprises an electrical resistance.
A cooling device as in any one of the above claims, wherein the ice tray (40) is produced from metal.
A cooling device as in any one of the above claims, wherein the metallic element (30) comprises a bimetallic strip or shape memory alloy.