KR20230131685A - Surface treated ice tray and ice maker including the same - Google Patents

Abstract

The present invention includes an ice-making tray body with an ice-making groove in a space where ice is made, and the inner surface of the ice-making groove of the ice-making tray body is formed with nano-sized bumps by surface treatment, wherein the bumps or bumps are formed. An ice-making tray including a superhydrophobic structure in which the contact angle between holes and water particles exceeds at least 90 degrees and an ice-making machine including the same are provided.

Description

Surface treated ice tray and ice maker including the same {SURFACE TREATED ICE TRAY AND ICE MAKER INCLUDING THE SAME}

The present invention relates to a surface-treated ice-making tray and an ice-making machine including the same.

In general, a refrigerator is a device that stores food at low temperatures to prevent food deterioration at room temperature. Recently, products equipped with refrigerator ice makers that provide ice to users separately from food have been released.

An ice maker for a refrigerator includes an ice-making tray with a plurality of ice-making grooves for automatically receiving water and making ice of a certain size, and an ice box provided at the bottom of the ice-making tray to store ice moved by a moving motor.

Here, there may be two methods for moving the ice made in the ice-making tray. The ice-making tray itself is twisted using the above-described moving motor to separate the ice-made ice from the ice-making groove, and then the ice below it is separated. The twist type is used to drop the ice into a box, and the ice is made by applying a certain amount of ice heat using a moving heater to an ice making tray made of metal, separating the ice from the ice making groove and rotating a separate ice ejector. This is the type of heater that is pushed to one side of the tray and dropped into the ice box below.

Republic of Korea Patent Publication No. 10-2019-0071427 (published on June 24, 2019) discloses ‘an ice maker equipped with an ejector pin and a refrigerator including the same.’

However, the conventional ice maker had a problem in which ice was not sufficiently separated from the ice-making groove of the ice-making tray due to incomplete heating during the ice-moving process, resulting in defective ice-moving.

Republic of Korea Patent Publication No. 10-2019-0071427 (2019.06.24. Publication date)

The present invention was developed to solve the above-described technical problem, by treating the surface of the ice tray of the ice maker so that the ice made from the ice maker can be easily removed, so that the ice made from the ice maker can be easily removed from the ice maker in the process of removing the ice from the ice making groove. The purpose is to provide an ice-making tray that can fundamentally prevent defective ice-making and an ice-making machine including the same.

The ice maker according to the present invention includes an ice-making tray body with an ice-making groove in a space where ice is made, and nano-sized bumps are formed on the inner surface of the ice-making groove of the ice-making tray body by surface treatment. , the contact angle between the irregularities or holes and the water particles may include a superhydrophobic structure in which the contact angle exceeds at least 90 degrees.

In one embodiment of the present invention, the contact angle of the water particles may be greater than 90 degrees and less than 150 degrees.

In one embodiment of the present invention, surface treatment of the ice-making groove may be performed by anodizing.

In one embodiment of the present invention, the inner surface of the ice-making groove may not be sealed and may be omitted.

In one embodiment of the present invention, the ice-making tray may include one or more of stainless steel, aluminum, and carbon.

In one embodiment of the present invention, the nano-sized bumps of the ice-making groove may be treated with a sodium hydroxide solution.

In one embodiment of the present invention, the ice-making groove may have a cross-sectional shape whose diameter increases from the bottom surface.

Here, in one embodiment of the present invention, the bottom surface may be formed in a shape that protrudes upward.

In one embodiment of the present invention, the inner peripheral surface of the ice-making groove may be insulated.

In one embodiment of the present invention, an air layer may be formed between the unevenness and the adjacent unevenness while in contact with the water particles.

In one embodiment of the present invention, at least a portion of the ice-making tray may be anodized.

In one embodiment of the present invention, the irregularities may be formed by laser beam irradiation.

Additionally, the present invention provides an ice maker including the ice making tray.

Meanwhile, the present invention provides a method for manufacturing the ice-making tray,

A pretreatment step of removing surface foreign substances of an ice-making tray containing an aluminum alloy material;

Removing the oxide layer and forming nano-sized bumps by immersing in a hydroxide solution (NaOH);

anodizing the ice-making tray; and

It may include the step of pressure coating the silicone-based water repellent material at a temperature of at least 100 degrees Celsius.

In one embodiment of the present invention, the anodizing process may be performed by controlling the current density using the ice-making tray as an anode and titanium as a cathode.

The surface-treated ice-making tray and the ice maker including the same according to the present invention treat the surface of the ice-making tray of the ice maker so that the ice made from the ice maker can be easily taken out, so that the ice made from the ice maker is removed from the ice-making groove of the ice maker. It has the effect of fundamentally preventing poor moving.

1 is a schematic perspective view showing an ice maker according to an embodiment of the present invention;
Figure 2 is a schematic cross-sectional view showing an ice maker according to an embodiment of the present invention;
3 is a schematic partial cross-sectional view of an ice-making tray according to an embodiment of the present invention;
Figure 4 is a cross-sectional view taken along 'A' in Figure 3;
Figure 5 is an exemplary diagram showing the contact angle between water particles and irregularities according to an embodiment of the present invention;
Figure 6 is a flowchart showing the surface treatment process of the ice-making tray according to an embodiment of the present invention;
Figure 7 is a photograph taken with a scanning electron microscope (SEM) from the top of the unevenness formed on the ice-making tray manufactured according to an embodiment of the present invention;
Figure 8 is a photograph taken with a scanning electron microscope (SEM) of the unevenness formed on the ice-making tray manufactured according to an embodiment of the present invention from the cut surface.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, when describing embodiments of the present invention, if detailed descriptions of related known configurations or functions are judged to impede understanding of the embodiments of the present invention, the detailed descriptions will be omitted.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. Additionally, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present application. No.

As described above, the conventional ice-making tray is made of a metal material with a high coefficient of thermal expansion, so it shrinks relatively more when the temperature is lowered, and the ice-making water expands in volume during the ice creation process, so the ice-making tray There was a problem that moving became more difficult due to the contraction of the ice and the expansion of the ice.

Accordingly, in the present invention, the inner surface of the ice-making groove of the ice-making tray is treated with aluminum anodization to form nano-sized bumps and minimize the surface contact area, so that water droplets do not seep into the inside of the lotus leaf and drip from the surface. The above-described problem can be solved by allowing ice to easily move from the ice-making groove of the ice-making tray through the lotus effect.

The ice maker 100 according to the present invention may be installed in at least one of a refrigerator compartment and a freezer compartment. In this embodiment, the ice maker 100 may be installed in the upper left corner of the refrigerating compartment of a refrigerator (not shown), but the ice maker 100 is not limited to this.

The ice maker 100 can receive ice-making water from the refrigerator, and can produce the ice by turning the ice-making water into ice using cold air supplied to the storage compartment from the refrigeration cycle of the refrigerator.

An ice box (not shown) in which ice transferred from the ice maker 100 is stored may be installed in the storage compartment of such a refrigerator. The ice box may be placed below the ice maker 100. The ice box may be formed in a cylindrical shape with an open top. Ice made in the ice maker 100 may be transferred from the ice maker 100 to the ice box, and may be accommodated and stored in the ice box.

An auger may be placed within the ice box. The auger may be installed in the ice box to be rotatable in a circumferential direction. Both ends of the auger may be rotatably coupled to both sides of the ice box. A spiral groove may be formed on the outer peripheral surface of the auger. When the auger rotates, it can transfer ice stored in the ice box to the outside of the ice box through the spiral groove. The auger may be rotated by the driving force of an auger motor installed on one side of the ice box.

Hereinafter, 'ice making' may mean that the ice water contained in the ice making groove 15 changes into ice, and 'freezing' may mean that the ice in the ice making groove 15 is separated from the ice making groove 15.

Figure 1 is a schematic perspective view showing an ice maker according to an embodiment of the present invention, and Figure 2 is a schematic cross-sectional view showing an ice maker according to an embodiment of the present invention.

Referring to these drawings, the ice maker 100 according to an embodiment of the present invention includes a control box 101 equipped with various electrical products including a driving unit, a space provided on one side of the control box 101, and a space where ice is made. It may include an ice-making tray 200 in which the ice-making groove 210 is formed, and a cooling unit 130 and a heater unit 120 disposed below the ice-making tray 200.

The control box 110 may be formed in a substantially hexahedral square cylinder shape. The control box 101 has an empty structure, so that an internal space in which various electrical products including the driving unit can be accommodated can be formed. A control unit (not shown) may be placed in the internal space of the control box 101. The control unit may include a printed circuit board. The control unit may control the operation of the ice maker 100.

The ice maker 100 may include an ice making tray 200. An ice-making groove 210 may be formed on the upper surface of the ice-making tray 200 to accommodate ice-making water. The ice making groove 210 may be formed of a plurality of ice making grooves 210 spaced apart from each other along the length of the ice making tray 200. Here, according to the present invention, nano-sized irregularities (H, bumps) may be formed on the inner peripheral surface of the ice-making groove 210 by surface treatment by anodizing in order to facilitate the removal of ice-made ice. This will be described in more detail below with reference to the drawings.

The ice-making groove 210 of the ice-making tray 200 has a cross-sectional shape that increases in diameter from the bottom to the top, for example, an inverted triangle shape and a shape that protrudes from the bottom in the form of an oval-shaped hemisphere. It can make moving easy.

Furthermore, according to the present invention, the inner peripheral surface of the ice-making groove 210 of the ice-making tray 200 can be insulated. The upper surface of the ice-making water supplied to the ice-making groove 210 is exposed to the temperature of the freezer, and the remaining part, that is, the inner surface of the ice-making groove 210, is insulated so that ice-making progresses gradually in one direction, making it more transparent and clean. Can create ice.

Figure 3 is a schematic partial cross-sectional view of an ice-making tray according to an embodiment of the present invention, Figure 4 is a cross-sectional view 'A' of Figure 3, and Figure 5 shows the contact angle between water particles and irregularities according to an embodiment of the present invention. This is an example diagram.

Referring to these drawings, as described above, the ice maker 100 according to an embodiment of the present invention is anodized using a phosphate-based electrolyte solution on the inner surface of the ice making groove 210 of the ice making tray 200 made of aluminum. Irregularities (H, bumps) of any size may be formed.

The ice-making tray 200 with nano-sized irregularities according to the present invention maintains a contact angle with the ice-making water exceeding approximately 90 degrees, thereby maintaining the water particles in a superhydrophobic state floating on the irregularities. This can prevent ice-making water from being adsorbed on the surface of the ice-making tray 200 during the ice-making process. In one example, the ice-making tray 200, preferably having irregularities according to the present invention, may be approximately 90 degrees or more, as shown in FIG. 5, and more preferably greater than 90 degrees to within 150 degrees. It can be maintained in the range of .

That is, since the ice-making water that makes ice is generally a liquid, it has a contact angle to contact the metal of the ice-making tray 200 and has hydrophilic characteristics. At this time, if the contact angle is less than 90, the ice-making water spreads on the metal surface and becomes hydrophilic due to the surface tension, but the ice-making tray 200 of the present invention has a contact angle with the ice-making water that exceeds at least 90 degrees. By maintaining a superhydrophobic surface, it is possible to maximize the surface tension of the ice-making water and improve ice-making efficiency.

The surface treatment of the ice-making tray 200 using the anodizing method may be performed, for example, by controlling the current density using the ice-making tray 200 as an anode and titanium as a cathode.

Furthermore, according to the present invention, part or all of the ice maker 100 including the ice making tray 200 surface treated by the anodizing method may also be surface treated by the anodizing method. That is, the ice maker 100 and the adjacent area where the ice making tray 100 is generally installed are provided with separate heaters to prevent condensation due to internal moisture condensation, etc., but the ice making tray 100 according to the present invention is included. Since the surface of the ice maker 100 disposed adjacent to or on at least a portion of the ice maker 100 is surface treated using the anodic oxidation method described above, a separate heater, etc. can be eliminated.

Meanwhile, nano-sized bumps (H) formed on the ice-making tray 100 according to the present invention can be formed to a predetermined depth and width by irradiating a laser beam in one direction. In one example, nano-sized bumps (H) can be formed by adjusting the output of the laser beam, the frequency of the laser, the irradiation time of the laser, the spot size of the laser, and the processing speed.

At this time, depending on the case, the depth and width of the unevenness (H), that is, the surface roughness, can be adjusted by adjusting the output of the laser beam. In other words, the surface of the concavo-convex (H) processed by a high-power laser may have greater roughness than the surface of the concave-convex (H) processed multiple times by a low-output laser.

Furthermore, the unevenness (H) can be formed by varying the depth by two or more laser irradiations. This means that it is deeper than the depth that can be formed with one laser irradiation, and for this, the area to which the laser is irradiated may overlap. A method of irradiating the surface of the ice-making tray 100 by overlapping lasers may be a method of irradiating two or more laser lights at intervals of time or distance. Meanwhile, the rate at which lasers overlap can be referred to as the overlap ratio.

This means that the spot size, frequency, scan interval, and scan speed of the irradiated laser may be factors that determine the overlap rate of the laser, and the predetermined depth may be determined by the overlap rate. For example, the shorter the frequency period and the faster the scan speed, the lower the overlap rate may be. Conversely, the longer the frequency period and the slower the scan speed, the higher the overlap rate can be. Here, a high overlap ratio means that the amount of energy emitted from the laser increases in proportion to the unit area, so the predetermined depth can be reached by selectively determining the laser frequency and scan speed.

In addition, the predetermined depth can be reached even when repeated processing is performed under the above laser conditions. Therefore, the depth of the unevenness (H) formed by laser irradiation takes into account conditions such as the material of the ice-making tray 100, the output of the laser, the frequency of the laser, the laser spot size, the scan interval, the scan speed, and the number of repeated processing. Therefore, it can be a factor that can be selectively determined.

Below, a specific manufacturing method of the ice-making tray 200 whose surface is treated using the anodic oxidation method described above will be described.

Figure 6 is a flowchart showing the surface treatment process of an ice-making tray according to an embodiment of the present invention.

First, the manufacturing method of the ice-making tray 200 according to the present invention includes a pretreatment step (S10) of removing surface foreign substances of the ice-making tray 200 made of aluminum alloy, removing the oxide layer by immersing it in a hydroxide solution (NaOH), and removing the nano-oxide layer. It may include forming bumps of any size (S20), anodizing the ice-making tray 200 (S30), and applying pressure coating with a silicone-based water repellent material at a temperature of at least 100 degrees (S40). You can.

The pretreatment process (S10) may be performed using a strong acid aqueous solution to remove foreign substances or oxide layers on the surface of the ice-making tray 200 made of aluminum metal.

Subsequently, the ice-making tray 200 on which the pre-treatment process has been performed may be immersed in a hydroxide solution (NaOH) using a phosphate-based electrolyte solution to remove the oxide film on the surface of the ice-making tray 200 (S20). In this way, when the ice-making tray 200 is immersed in a hydroxide solution (NaOH), the surface roughness increases due to a pitting phenomenon. That is, the nano-sized irregularities described above are formed on the inner surface of the ice-making groove 210 of the ice-making tray 200.

Afterwards, a process of surface treating the ice-making tray 200 on which nano-sized irregularities are formed by anodizing is performed (S30). In a preferred example, this can be performed by controlling the current density using the ice-making tray 200 as the anode and titanium as the cathode.

Finally, the nano-sized irregularities formed in this way undergo a process of coating tube-shaped pores with a silicone-based water repellent material made of nanoparticles by pressure at a temperature of 100 degrees or more (S40). Therefore, the silicone-based water repellent material may penetrate between the tube-shaped pores and the pores due to the fitting phenomenon of the hydroxide solution (NaOH), thereby forming and expanding an air layer similar to the lotus leaf effect described above.

In other words, the fine pores on the surface of the ice-making tray 200 made of anodized aluminum metal and the pores caused by immersion in a hydroxide solution (NaOH) are added to enlarge the overall pore size, allowing ice to be easily released from the ice-making groove 210. You can make it move.

In the present invention, in order to confirm the nano-sized irregularities formed on the surface of the ice-making tray 200 manufactured as above, the appearance after surface treatment by anodizing method, as shown in FIGS. 7 and 8, is examined using a scanning electron microscope. This was confirmed through (SEM).

Above, an embodiment of the present invention has been described in detail with reference to the attached drawings. However, the embodiments of the present invention are not necessarily limited to the above-described embodiment, and it is natural that various modifications and equivalent implementations can be made by those skilled in the art. will be. Therefore, the true scope of rights of the present invention will be determined by the claims described later.

100: Ice maker 101: Control box
110: Eject pin 120: Heater unit
130: Cooling unit 200: Ice-making tray
210: Ice making groove C: Ice surface
H: uneven

Claims (14)

It includes an ice-making tray body formed with an ice-making groove in a space where ice is made,
Nano-sized bumps are formed on the inner surface of the ice-making groove of the ice-making tray body by surface treatment,
An ice-making tray comprising a superhydrophobic structure in which the contact angle between the irregularities or holes and the water particles exceeds at least 90 degrees.
According to claim 1,
An ice-making tray wherein the contact angle of the water particles is greater than 90 degrees and less than 150 degrees.
According to claim 1,
An ice-making tray in which the surface treatment of the ice-making groove is performed by anodizing.
According to claim 1,
An ice-making tray in which the inner surface of the ice-making groove is not sealed.
According to claim 1,
The ice maker includes one or more of stainless steel, aluminum, and carbon.
According to claim 1,
An ice-making tray in which nano-sized bumps of the ice-making groove are treated with a sodium hydroxide solution.
According to claim 1,
The ice-making groove is an ice-making tray whose cross-section has a shape whose diameter increases from the bottom surface.
According to claim 7,
An ice-making tray wherein the bottom surface is formed in a shape that protrudes upward.
According to claim 1,
The ice-making groove is an ice-making tray whose inner peripheral surface is insulated.
According to claim 1,
An ice-making tray wherein at least a portion of the ice-making tray is anodized.
According to claim 1,
An ice-making tray in which the irregularities are formed by laser beam irradiation.
A refrigerator comprising an ice maker according to any one of claims 1 to 11.
A pretreatment step of removing surface foreign substances of an ice-making tray containing an aluminum alloy material;
Removing the oxide layer by immersing in a hydroxide solution (NaOH);
forming nano-sized bumps on the ice-making tray by anodizing;
A method of manufacturing an ice tray comprising the step of pressure coating a silicone-based water repellent material at a temperature of at least 100 degrees Celsius.
According to claim 13,
The anodizing process is,
A method of manufacturing an ice-making tray performed by controlling current density using the ice-making tray as an anode and titanium as a cathode.