Patent Description:
In general, refrigerators are home appliances for storing food at a low temperature in a storage space that is covered by a door. The refrigerator may cool the inside of the storage space by using cold air to store the stored food in a refrigerated or frozen state. Generally, an ice maker for making ice is provided in the refrigerator. The ice maker makes ice by cooling water after accommodating the water supplied from a water supply source or a water tank into a tray. The ice maker separates the made ice from the ice tray in a heating manner or twisting manner.

The ice maker through which water is automatically supplied, and the ice automatically separated may be, for example, opened upward so that the mode ice is pumped up.

As described above, the ice made in the ice maker may have at least one flat surface such as crescent or cubic shape.

When the ice has a spherical shape, it is more convenient to use the ice, and also, it is possible to provide different feeling of use to a user. Also, even when the made ice is stored, a contact area between the ice cubes may be minimized to minimize a mat of the ice cubes.

An ice maker is disclosed in <CIT> (hereinafter, referred to as a "prior art document <NUM>") that is a prior art document.

The ice maker disclosed in the prior art document <NUM> includes an upper tray in which a plurality of upper cells, each of which has a hemispherical shape, are arranged, and which includes a pair of link guide parts extending upward from both side ends thereof, a lower tray in which a plurality of upper cells, each of which has a hemispherical shape and which is rotatably connected to the upper tray, a rotation shaft connected to rear ends of the lower tray and the upper tray to allow the lower tray to rotate with respect to the upper tray, a pair of links having one end connected to the lower tray and the other end connected to the link guide part, and an upper ejecting pin assembly connected to each of the pair of links in at state in which both ends thereof are inserted into the link guide part and elevated together with the upper ejecting pin assembly.

In the prior art document <NUM>, although the spherical ice is made by the hemispherical upper cell and the hemispherical lower cell, since the ice is made at the same time in the upper and lower cells, bubbles containing water are not completely discharged but are dispersed in the water to make opaque ice.

The ice maker disclosed in the prior art document <NUM> includes an ice making plate and a heater for heating a lower portion of water supplied to the ice making plate.

In the case of the ice maker disclosed in the prior art document <NUM>, water on one surface and a bottom surface of an ice making block is heated by the heater in an ice making process. Thus, when solidification proceeds on the surface of the water, and also, convection occurs in the water to make transparent ice.

When growth of the transparent ice proceeds to reduce a volume of the water within the ice making block, the solidification rate is gradually increased, and thus, sufficient convection suitable for the solidification rate may not occur.

Thus, in the case of the prior art document <NUM>, when about <NUM>/<NUM> of water is solidified, a heating amount of heater increases to suppress an increase in the solidification rate.

However, according to the prior art document <NUM>, when only the volume of water is reduced, the heating amount of heater may increase, and thus, it may be difficult to make ice having uniform transparency according to shapes of ice.

<CIT> presents an automatic ice making machine having a constitution in which a water to be frozen stored within a water tank is fed under pressure to a distributor pipe via a pump and injected through injection holes formed along said distributor pipe into a freezing chamber cooled by an evaporator connected to a freezing system, to form ice cakes within said freezing chamber, while part of the freezing water which is not frozen within said freezing chamber is fed back to said water tank for recirculation, characterized in that said ice making chamber consists of a first freezing chamber having formed thereon a multiplicity of downwardly opening first freezing cells of a predetermined recessed shape, with said evaporator disposed on its rear surface; and a second freezing chamber having formed thereon a multiplicity of second freezing cells of a predetermined recessed shape, which is disposed relative to said first freezing chamber such that the former may be moved closer to or spaced from the latter, wherein said second freezing cells close the corresponding first freezing cells from downside, respectively, to define ice forming spaces of spherical or polyhedral shape therebetween during the freezing operation.

<CIT> presents an ice maker and ice making method using the same. The ice maker includes an upper tray, a lower tray, and a rotation shaft. Upper cells of hemispherical shapes are arrayed in the upper tray. Lower cells of hemispherical shapes are arrayed in the lower tray that is rotatably connected to the upper tray. The rotation shaft is connected to a rear end of the lower tray and a rear end of the upper tray to rotate the lower tray relative to the upper tray. A rotation guide part rounded with a predetermined curvature is disposed in a region where the lower tray contacts the upper tray while the lower tray is rotated.

<CIT> presents an ice maker including: an upper tray formed with a plurality of hemispherical first depressions; a lower tray rotatably combined with the upper tray, and a plurality of hemispherical recesses formed on the lower tray, the plurality of the second recesses are respectively closely attached to the plurality of the first recesses to form a plurality of spherical lattices; a drive unit, which is connected to at least one of the upper tray and the lower tray. The shaft connection of the tray is used to rotate one or both of the upper tray and the lower tray; the water supply part supplies water for making ice to the plurality of the grids; and the ejection unit is arranged on the outside of the grid is used to separate the ice cubes formed in the grid to the outside.

<CIT> presents an ice maker provided in a refrigerator. The ice maker includes: first and second ice making units configured to include ice making trays, heaters heating the ice making trays for deicing, and ejectors ejecting made ice from the ice making trays, respectively, wherein a plurality of first ice making grooves are formed in the ice making tray of the first ice making unit, and a plurality of second ice making grooves are formed in the ice making tray of the second ice making unit, the plurality of second ice making grooves having a shape different from that of the plurality of first ice making grooves.

<CIT> presents an ice maker for use in a domestic refrigerator/freezer that makes clear ice bodies. The ice maker comprises a support arranged to have an ice body formed thereon. The support is refrigerated to a below-freezing temperature and a container adapted to hold a body of water is moved to move liquid water contained therein uniformly about the support suitable to cause a clear substantially symmetrical ice body to build up outwardly on the refrigerated support.

Embodiments provide a refrigerator which is capable of making ice having uniform transparency as a whole regardless of shapes of the ice and a method for manufacturing the same.

Embodiments also provide a refrigerator which is capable of making spherical ice and has uniform transparency of the spherical ice for unit height and a method for manufacturing the same.

Embodiments also provide a refrigerator in which a heating amount of transparent ice heater and/or cooling power of the cooler vary in response to the change in heat transfer amount between water in an ice making cell and cold air in a storage chamber, thereby making ice having uniform transparency as a whole and a method for manufacturing the same.

The technical problem of this invention is to avoid the situation in which ice inside an ice making cell is melted and then re-frozen due an abnormal state in the atmosphere which deteriorate transparency of the ice, and a method for manufacturing the same.

A refrigerator according to one aspect may include a first tray and a second tray forming an ice making cell. A heater may be disposed at one side of the first tray or the second tray.

The heater is turned on in at least partial section while a cold air supply part supplies cold air to the ice making cell so that bubbles dissolved in the water within the ice making cell moves from a portion, at which the ice is made, toward the water that is in a liquid state to make transparent ice.

The first tray may form a portion of the ice making cell, which is a space in which water is phase-changed into ice by the cold air, and the second tray may form another portion of the ice making cell. In the ice making process, the second tray is in contact with the first tray, and in the ice separation process, the second tray is spaced apart from the first tray. The second tray is connected to the driver to receive power from the driver.

The second tray may move from the water supply position to the ice making position by the operation of the driver. Also, the second tray may move from the ice making position to the ice making position by the operation of the driver. The water supply of the ice making cell is performed while the second tray moves to the water supply position.

After the water supply is completed, the second tray moves to the ice making position. After the second tray moves to the ice making position, the cold air supply part supplies cold air to the ice making cell.

When the ice making in the ice making cell is completed, the second tray may move to the ice separation position in a forward direction to take out the ice of the ice making cell. After the second tray moves to the ice separation position, the second tray may move to the water supply position in a reverse direction, and water supply may be started again.

The refrigerator according to the invention further includes a full ice detection part.

When the full ice of the ice bin is detected by the full ice detection part, the second tray moves to the ice separation position only after the ice making is completed.

The full ice detection part may detect the full ice while the second tray moves from the ice making position to the ice separation position. After the second tray moves to the ice separation position, the full ice detection part may repetitively perform the full ice detection at a predetermined period. After the second tray moves to the ice separation position, the second tray may move to the water supply position to stand by.

When a set time elapses after the second tray moves to the water supply position, whether ice is fully refilled may be detected by the full ice detection part. In the result of whether the ice is fully refilled, when the ice full is detected, the second tray may stand by at the water supply position. On the other hand, when the ice full is not detected, the water supply may start in the state in which the second tray is disposed at the water supply position.

The full ice detection part may include a full ice detection lever that rotates by receiving power of the driver. An extension line of a rotation center of the full ice detection lever may be parallel to an extension line of a rotation center of the second tray.

The full ice detection lever may include a first body extending in a direction parallel to the extension line of the rotation center of the second tray and a pair of second bodies respectively extending from both ends of the first body. One of the pair of second bodies may be connected to the driver. While the full ice detection lever rotates, the first body may be disposed lower than the second tray. The full ice detection lever may rotate to a full ice detection position, and at the full ice detection position, the first body may be inserted into the ice bin. A maximum distance between an upper end of the ice bin and the first body may be less than a radius of ice generated in the ice making cell.

In this embodiment, one or more of cooling power of the cold air supply part, a heating amount of the heater may be controlled to vary according to a mass per unit height of water within the ice making cell.

As one example, a heating amount of heater may be controlled so that the heating amount of heater when a mass per unit height of water is large is less than that of heater when a mass per unit height of the water is small while maintaining the same cooling power of the cold air supply part. As another example, the cooling power of the cold air supply part may be controlled so that the cooling power of the cold air supply part when the mass per unit height of the water is large is greater than that of the cold air supply part when the mass per unit height of the water is small while the heating amount of heater is uniformly maintained.

When a heat transfer amount between the cold air within the storage chamber and the water of the ice making cell increases, the heating amount of heater increases, and when the heat transfer amount between the cold air within the storage chamber and the water of the ice making cell decreases, the heating amount of heater decreases so as to maintain an ice making rate of the water within the ice making cell within a predetermined range that is less than an ice making rate when the ice making is performed in a state in which the heater is turned off.

When a total volume of ice separated into the ice bin reaches a set full ice reference value, the ice bin may be determined as a full ice state.

The total volume of the separated ice may correspond a volume of the ice making cell x the number of times of separation of the ice. The full ice reference value may be greater than <NUM>% of a total volume of the ice bin, and may a value obtained by subtracting the volume of the ice making cell from the total volume of the ice bin may be set.

A method for controlling a refrigerator of the invention is also defined by the independent claim <NUM>.

The heater is turned on in at least partial section in the performing of the ice making so that bubbles dissolved in the water within the ice making cell moves from a portion, at which the ice is made, toward the water that is in a liquid state to make transparent ice.

The method may further include, in the determining of whether the ice bin is full, when the full ice of the ice bin is detected, moving the second tray to the water supply position to stand by after the second tray moves to the ice separation position.

The method may further include, after the second tray moves to the ice separation position, redetermining whether the ice bin is full.

The method may further include, according to the result of the redetermining of whether the ice bin is full, if the ice full of the ice bin is not detected, starting the water supply.

The method may further include, according to the result of the redetermining of whether the ice bin is full, if the ice full of the ice bin is detected, moving the second tray to the water supply position to stand by.

Since the heater is turned on in at least a portion of the sections while the cold air supply part supplies cold air, the ice making rate may be delayed by the heat of the heater so that the bubbles dissolved in the water inside the ice making cell move toward the liquid water from the portion at which the ice is made, thereby making the transparent ice.

Particularly, one or more of the cooling power of the cold air supply part and the heating amount of heater may be controlled to vary according to the mass per unit height of water in the ice making cell to make the ice having the uniform transparency as a whole regardless of the shape of the ice making cell.

Also, the heating amount of transparent ice heater and/or the cooling power of the cold air supply part may vary in response to the change in the heat transfer amount between the water in the ice making cell and the cold air in the storage chamber, thereby making the ice having the uniform transparency as a whole. By completing the ice making even when the full ice is detected, the situation in which ice inside an ice making cell is melted and then re-frozen due to an abnormal state in the athmosphere to deteriorate transparency is avoided.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. Exemplary embodiments of the present invention will be described below in more detail with reference to the accompanying drawings. It is noted that the same or similar components in the drawings are designated by the same reference numerals as far as possible even if they are shown in different drawings.

<FIG> is a front view of a refrigerator according to an embodiment.

Referring to <FIG>, a refrigerator according to an embodiment may include a cabinet <NUM> including a storage chamber and a door that opens and closes the storage chamber.

The storage chamber may include a refrigerating compartment <NUM> and a freezing compartment <NUM>. The refrigerating compartment <NUM> is disposed at an upper side, and the freezing compartment <NUM> is disposed at a lower side. Each of the storage chamber may be opened and closed individually by each door. For another example, the freezing compartment may be disposed at the upper side and the refrigerating compartment may be disposed at the lower side. Alternatively, the freezing compartment may be disposed at one side of left and right sides, and the refrigerating compartment may be disposed at the other side.

The freezing compartment <NUM> may be divided into an upper space and a lower space, and a drawer <NUM> capable of being withdrawn from and inserted into the lower space may be provided in the lower space.

The door may include a plurality of doors <NUM>, <NUM>, <NUM> for opening and closing the refrigerating compartment <NUM> and the freezing compartment <NUM>. The plurality of doors <NUM>, <NUM>, and <NUM> may include some or all of the doors <NUM> and <NUM> for opening and closing the storage chamber in a rotatable manner and the door <NUM> for opening and closing the storage chamber in a sliding manner. The freezing compartment <NUM> may be provided to be separated into two spaces even though the freezing compartment <NUM> is opened and closed by one door <NUM>.

In this embodiment, the freezing compartment <NUM> may be referred to as a first storage chamber, and the refrigerating compartment <NUM> may be referred to as a second storage chamber.

The freezing compartment <NUM> may be provided with an ice maker <NUM> capable of making ice. The ice maker <NUM> may be disposed, for example, in an upper space of the freezing compartment <NUM>.

An ice bin <NUM> in which the ice made by the ice maker <NUM> drops to be stored may be disposed below the ice maker <NUM>. A user may take out the ice bin <NUM> from the freezing compartment <NUM> to use the ice stored in the ice bin <NUM>.

The ice bin <NUM> may be mounted on an upper side of a horizontal wall that partitions an upper space and a lower space of the freezing compartment <NUM> from each other. Although not shown, the cabinet <NUM> is provided with a duct supplying cold air to the ice maker <NUM>. The duct guides the cold air heat-exchanged with a refrigerant flowing through the evaporator to the ice maker <NUM>. For example, the duct may be disposed behind the cabinet <NUM> to discharge the cold air toward a front side of the cabinet <NUM>. The ice maker <NUM> may be disposed at a front side of the duct.

Although not limited, a discharge hole of the duct may be provided in one or more of a rear wall and an upper wall of the freezing compartment <NUM>. Although the above-described ice maker <NUM> is provided in the freezing compartment <NUM>, a space in which the ice maker <NUM> is disposed is not limited to the freezing compartment <NUM>. For example, the ice maker <NUM> may be disposed in various spaces as long as the ice maker <NUM> receives the cold air.

<FIG> is a perspective view of the ice maker according to an embodiment, <FIG> is a perspective view illustrating a state in which the bracket is removed from the ice maker of <FIG>, and <FIG> is an exploded perspective view of the ice maker according to an embodiment. <FIG> is a cross-sectional view taken along line A-A of <FIG> so as to show a second temperature sensor installed in the ice maker according to an embodiment.

<FIG> is a longitudinal cross-sectional view of the ice maker when a second tray is disposed at a water supply position according to an embodiment.

Referring to <FIG>, each component of the ice maker <NUM> may be provided inside or outside the bracket <NUM>, and thus, the ice maker <NUM> may constitute one assembly.

The bracket <NUM> may be installed at, for example, the upper wall of the freezing compartment <NUM>. The water supply part <NUM> may be installed on an upper side of an inner surface of the bracket <NUM>. The water supply part <NUM> may be provided with an opening in each of an upper side and a lower side to guide water, which is supplied to an upper side of the water supply part <NUM>, to a lower side of the water supply part <NUM>. The upper opening of the water supply part <NUM> may be greater than the lower opening to limit a discharge range of water guided downward through the water supply part <NUM>. A water supply pipe through which water is supplied may be installed to the upper side of the water supply part <NUM>. The water supplied to the water supply part <NUM> may move downward. The water supply part <NUM> may prevent the water discharged from the water supply pipe from dropping from a high position, thereby preventing the water from splashing. Since the water supply part <NUM> is disposed below the water supply pipe, the water may be guided downward without splashing up to the water supply part <NUM>, and an amount of splashing water may be reduced even if the water moves downward due to the lowered height.

The ice maker <NUM> may include an ice making cell 320a in which water is phase-changed into ice by the cold air.

The ice maker <NUM> may include a first tray <NUM> defining at least a portion of a wall providing the ice making cell 320a and a second tray <NUM> defining at least the other portion of a wall providing the ice making cell 320a. Although not limited, the ice making cell 320a may include a first cell 320b and a second cell 320c.

The first tray <NUM> may define the first cell 320b, and the second tray <NUM> may define the second cell 320c.

The second tray <NUM> may be disposed to be relatively movable with respect to the first tray <NUM>. The second tray <NUM> may linearly rotate or rotate. Hereinafter, the rotation of the second tray <NUM> will be described as an example.

For example, in an ice making process, the second tray <NUM> may move with respect to the first tray <NUM> so that the first tray <NUM> and the second tray <NUM> contact each other. When the first tray <NUM> and the second tray <NUM> are in contact with each other, the complete ice making cell see 320a may be defined.

On the other hand, the second tray <NUM> may move with respect to the first tray <NUM> during the ice making process after the ice making is completed, and the second tray <NUM> may be spaced apart from the first tray <NUM>.

In this embodiment, the first tray <NUM> and the second tray <NUM> may be arranged in a vertical direction in a state in which the ice making cell 320a is defined. Accordingly, the first tray <NUM> may be referred to as an upper tray, and the second tray <NUM> may be referred to as a lower tray.

A plurality of ice making cells 320a may be defined by the first tray <NUM> and the second tray <NUM>. In <FIG>, for example, three ice making cells 320a are provided.

When water is cooled by cold air while water is supplied to the ice making cell 320a, ice having the same or similar shape as that of the ice making cell 320a may be made.

In this embodiment, for example, the ice making cell 320a may be provided in a spherical shape or a shape similar to a spherical shape. In this case, the first cell 320b may be provided in a hemisphere shape or a shape similar to the hemisphere. Also, the second cell 320c may be provided in a hemisphere shape or a shape similar to the hemisphere. The ice making cell 320a may have a rectangular parallelepiped shape or a polygonal shape.

The ice maker <NUM> may further include a first tray case <NUM> coupled to the first tray <NUM>. For example, the first tray case <NUM> may be coupled to an upper side of the first tray <NUM>. The first tray case <NUM> may be manufactured as a separate part from the bracket <NUM> and then may be coupled to the bracket <NUM> or integrally formed with the bracket <NUM>.

The ice maker <NUM> may further include a first heater case <NUM>. An ice separation heater <NUM> may be installed in the second heater case <NUM>. The heater case <NUM> may be integrally formed with the first tray case <NUM> or may be separately formed.

The ice separation heater <NUM> may be disposed at a position adjacent to the first tray <NUM>. For example, the ice separation heater <NUM> may be a wire-type heater. For example, the ice separation heater <NUM> may be installed to contact the second tray <NUM> or may be disposed at a position spaced a predetermined distance from the second tray <NUM>. In some cases, the ice separation heater <NUM> may supply heat to the first tray <NUM>, and the heat supplied to the first tray <NUM> may be transferred to the ice making cell 320a.

The ice maker <NUM> may further include a first tray cover <NUM> disposed below the first tray <NUM>.

The first tray cover <NUM> may be provided with an opening corresponding to a shape of the ice making cell 320a of the first tray <NUM> and may be coupled to a bottom surface of the first tray <NUM>.

The first tray case <NUM> may be provided with a guide slot <NUM> which is inclined at an upper side and vertically extended at a lower side thereof. The guide slot <NUM> may be provided in a member extending upward from the first tray case <NUM>. A guide protrusion <NUM> of the first pusher <NUM> to be described later may be inserted into the guide slot <NUM>. Thus, the guide protrusion <NUM> may be guided along the guide slot <NUM>.

The first pusher <NUM> may include at least one extension part <NUM>. For example, the first pusher <NUM> may include an extension part <NUM> provided with the same number as the number of ice making cells 320a, but is not limited thereto. The extension part <NUM> may push out the ice disposed in the ice making cell 320a during the ice separation process. Accordingly, the extension part <NUM> may be inserted into the ice making cell 320a through the first tray case <NUM>. Therefore, the first tray case <NUM> may be provided with a hole <NUM> through which a portion of the first pusher <NUM> passes.

The guide protrusion <NUM> of the first pusher <NUM> may be coupled to the pusher link <NUM>. In this case, the guide protrusion <NUM> may be coupled to the pusher link <NUM> so as to be rotatable. Therefore, when the pusher link <NUM> moves, the first pusher <NUM> may also move along the guide slot <NUM>.

The ice maker <NUM> may further include a second tray case <NUM> coupled to the second tray <NUM>. The second tray case <NUM> may be disposed at a lower side of the second tray to support the second tray <NUM>. For example, at least a portion of the wall defining a second cell 320c of the second tray <NUM> may be supported by the second tray case <NUM>.

A spring <NUM> may be connected to one side of the second tray case <NUM>. The spring <NUM> may provide elastic force to the second tray case <NUM> to maintain a state in which the second tray <NUM> contacts the first tray <NUM>.

The ice maker <NUM> may further include a second tray case <NUM>.

The second tray <NUM> may include a circumferential wall <NUM> surrounding a portion of the first tray <NUM> in a state of contacting the first tray <NUM>. The second tray cover <NUM> may cover the circumferential wall <NUM>.

The ice maker <NUM> may further include a second heater case <NUM>. A transparent ice heater <NUM> may be installed in the second heater case <NUM>.

The transparent ice heater <NUM> will be described in detail.

The controller <NUM> according to this embodiment may control the transparent ice heater <NUM> so that heat is supplied to the ice making cell 320a in at least partial section while cold air is supplied to the ice making cell 320a to make the transparent ice.

An ice making rate may be delayed so that bubbles dissolved in water within the ice making cell 320a may move from a portion at which ice is made toward liquid water by the heat of the transparent ice heater <NUM>, thereby making transparent ice in the ice maker <NUM>. That is, the bubbles dissolved in water may be induced to escape to the outside of the ice making cell 320a or to be collected into a predetermined position in the ice making cell 320a.

When a cold air supply part <NUM> to be described later supplies cold air to the ice making cell 320a, if the ice making rate is high, the bubbles dissolved in the water inside the ice making cell 320a may be frozen without moving from the portion at which the ice is made to the liquid water, and thus, transparency of the ice may be reduced.

On the contrary, when the cold air supply part <NUM> supplies the cold air to the ice making cell 320a, if the ice making rate is low, the above limitation may be solved to increase in transparency of the ice. However, there is a limitation in which an ice making time increases.

Accordingly, the transparent ice heater <NUM> may be disposed at one side of the ice making cell 320a so that the heater locally supplies heat to the ice making cell 320a, thereby increasing in transparency of the made ice while reducing the ice making time.

When the transparent ice heater <NUM> is disposed on one side of the ice making cell 320a, the transparent ice heater <NUM> may be made of a material having thermal conductivity less than that of the metal to prevent heat of the transparent ice heater <NUM> from being easily transferred to the other side of the ice making cell 320a.

At least one of the first tray <NUM> and the second tray <NUM> may be made of a resin including plastic so that the ice attached to the trays <NUM> and <NUM> is separated in the ice making process.

At least one of the first tray <NUM> or the second tray <NUM> may be made of a flexible or soft material so that the tray deformed by the pushers <NUM> and <NUM> is easily restored to its original shape in the ice separation process.

The transparent ice heater <NUM> may be disposed at a position adjacent to the second tray <NUM>. For example, the transparent ice heater <NUM> may be a wire-type heater. For example, the transparent ice heater <NUM> may be installed to contact the second tray <NUM> or may be disposed at a position spaced a predetermined distance from the second tray <NUM>. For another example, the second heater case <NUM> may not be separately provided, but the transparent heater <NUM> may be installed on the second tray case <NUM>. In some cases, the transparent ice heater <NUM> may supply heat to the second tray <NUM>, and the heat supplied to the second tray <NUM> may be transferred to the ice making cell 320a.

The ice maker <NUM> may further include a driver <NUM> that provides driving force. The second tray <NUM> may relatively move with respect to the first tray <NUM> by receiving the driving force of the driver <NUM>.

A through-hole <NUM> may be defined in an extension part <NUM> extending downward in one side of the first tray case <NUM>. A through-hole <NUM> may be defined in the extension part <NUM> extending in one side of the second tray case <NUM>. The ice maker <NUM> may further include a shaft <NUM> that passes through the through-holes <NUM> and <NUM> together.

A rotation arm <NUM> may be provided at each of both ends of the shaft <NUM>. The shaft <NUM> may rotate by receiving rotational force from the driver <NUM>.

One end of the rotation arm <NUM> may be connected to one end of the spring <NUM>, and thus, a position of the rotation arm <NUM> may move to an initial value by restoring force when the spring <NUM> is tensioned.

A full ice detection lever <NUM> may be connected to the driver <NUM>. The full ice detection lever <NUM> may also rotate by the rotational force provided by the driver <NUM>.

The full ice detection lever <NUM> may be a swing type lever.

The full ice detection lever <NUM> crosses the inside of the ice bin <NUM> in a rotation process.

The full ice detection lever <NUM> may have a 'c' shape as a whole. For example, the full ice detection lever <NUM> may include a first portion <NUM> and a pair of second portions <NUM> extending in a direction crossing the first portion <NUM> at both ends of the first portion <NUM>. An extension direction of the first portion <NUM> may be parallel to an extension direction of a rotation center of the second tray <NUM>. Alternatively, an extension direction of the rotation center of the full ice detection lever <NUM> may be parallel to the extension direction of the rotation center of the second tray <NUM>. One of the pair of second portions <NUM> may be coupled to the driver <NUM>, and the other may be coupled to the bracket <NUM> or the first tray case <NUM>. The full ice detection lever <NUM> may rotate to detect ice stored in the ice bin <NUM>.

The ice maker <NUM> may further include a second pusher <NUM>. The second pusher <NUM> may be installed on the bracket <NUM>. The second pusher <NUM> may include at least one extension part <NUM>. For example, the second pusher <NUM> may include an extension part <NUM> provided with the same number as the number of ice making cells 320a, but is not limited thereto. The extension part <NUM> may push the ice disposed in the ice making cell 320a. For example, the extension part <NUM> may pass through the second tray case <NUM> to contact the second tray <NUM> defining the ice making cell and then press the contacting second tray <NUM>. Therefore, the second tray case <NUM> may be provided with a hole <NUM> through which a portion of the second pusher <NUM> passes.

The first tray case <NUM> may be rotatably coupled to the second tray case <NUM> with respect to the second tray supporter <NUM> and then be disposed to change in angle about the shaft <NUM>.

In this embodiment, the second tray <NUM> may be made of a non-metal material. For example, when the second tray <NUM> is pressed by the second pusher <NUM>, the second tray <NUM> may be made of a soft material which is deformable. Although not limited, the second tray <NUM> may be made of a silicon material.

Therefore, while the second tray <NUM> is deformed while the second tray <NUM> is pressed by the second pusher <NUM>, pressing force of the second pusher <NUM> may be transmitted to ice. The ice and the second tray <NUM> may be separated from each other by the pressing force of the second pusher <NUM>.

When the second tray <NUM> is made of the non-metal material and the flexible or soft material, the coupling force or attaching force between the ice and the second tray <NUM> may be reduced, and thus, the ice may be easily separated from the second tray <NUM>.

Also, if the second tray <NUM> is made of the non-metallic material and the flexible or soft material, after the shape of the second tray <NUM> is deformed by the second pusher <NUM>, when the pressing force of the second pusher <NUM> is removed, the second tray <NUM> may be easily restored to its original shape.

The first tray <NUM> may be made of a metal material. In this case, since the coupling force or the attaching force between the first tray <NUM> and the ice is strong, the ice maker <NUM> according to this embodiment may include at least one of the ice separation heater <NUM> or the first pusher <NUM>.

For another example, the first tray <NUM> may be made of a non-metallic material. When the first tray <NUM> is made of the non-metallic material, the ice maker <NUM> may include only one of the ice separation heater <NUM> and the first pusher <NUM>.

Alternatively, the ice maker <NUM> may not include the ice separation heater <NUM> and the first pusher <NUM>.

Although not limited, the first tray <NUM> may be made of a silicon material. That is, the first tray <NUM> and the second tray <NUM> may be made of the same material. When the first tray <NUM> and the second tray <NUM> are made of the same material, the first tray <NUM> and the second tray <NUM> may have different hardness to maintain sealing performance at the contact portion between the first tray <NUM> and the second tray <NUM>.

In this embodiment, since the second tray <NUM> is pressed by the second pusher <NUM> to be deformed, the second tray <NUM> may have hardness less than that of the first tray <NUM> to facilitate the deformation of the second tray <NUM>.

Referring to <FIG>, the ice maker <NUM> may further include a second temperature sensor <NUM> (or tray temperature sensor) for detecting a temperature of the ice making cell 320a. The second temperature sensor <NUM> may sense a temperature of water or ice of the ice making cell 320a.

The second temperature sensor <NUM> may be disposed adjacent to the first tray <NUM> to sense the temperature of the first tray <NUM>, thereby indirectly determining the water temperature or the ice temperature of the ice making cell 320a. In this embodiment, the water temperature or the ice temperature of the ice making cell 320a may be referred to as an internal temperature of the ice making cell 320a. The second temperature sensor <NUM> may be installed in the first tray case <NUM>.

In this case, the second temperature sensor <NUM> may contact the first tray <NUM> or may be spaced a predetermined distance from the first tray <NUM>. Alternatively, the second temperature sensor <NUM> may be installed in the first tray <NUM> to contact the first tray <NUM>.

Alternatively, when the second temperature sensor <NUM> may be disposed to pass through the first tray <NUM>, the temperature of the water or the temperature of the ice of the ice making cell 320a may be directly detected.

A portion of the ice separation heater <NUM> may be disposed higher than the second temperature sensor <NUM> and may be spaced apart from the second temperature sensor <NUM>. The wire <NUM> connected to the second temperature sensor <NUM> may be guided to an upper side of the first tray case <NUM>.

Referring to <FIG>, the ice maker <NUM> according to this embodiment may be designed so that a position of the second tray <NUM> is different from the water supply position and the ice making position.

For example, the second tray <NUM> may include a second cell wall <NUM> defining a second cell 320c of the ice making cell 320a and a circumferential wall <NUM> extending along an outer edge of the second cell wall <NUM>.

The second cell wall <NUM> may include a top surface 381a. The top surface 381a of the second cell wall <NUM> may be referred to as a top surface 381a of the second tray <NUM>.

The top surface 381a of the second cell wall <NUM> may be disposed lower than an upper end of the circumferential wall <NUM>.

The first tray <NUM> may include a first cell wall 321a defining a first cell 320b of the ice making cell 320a. The first cell wall 321a may include a straight portion 321b and a curved portion 321c. The curved portion 321c may have an arc shape having a radius of curvature at the center of the shaft <NUM>. Accordingly, the circumferential wall <NUM> may also include a straight portion and a curved portion corresponding to the straight portion 321b and the curved portion 321c.

The first cell wall 321a may include a bottom surface 321d. The bottom surface 321b of the first cell wall 321a may be referred to herein as a bottom surface 321b of the first tray <NUM>. The bottom surface 321d of the first cell wall 321a may contact the top surface 381a of the second cell wall 381a.

For example, at the water supply position as illustrated in <FIG>, at least portions of the bottom surface 321d of the first cell wall 321a and the top surface 381a of the second cell wall <NUM> may be spaced apart from each other. <FIG> illustrates that the entirety of the bottom surface 321d of the first cell wall 321a and the top surface 381a of the second cell wall <NUM> are spaced apart from each other. Accordingly, the top surface 381a of the second cell wall <NUM> may be inclined to form a predetermined angle with respect to the bottom surface 321d of the first cell wall 321a.

Although not limited, the bottom surface 321d of the first cell wall 321a may be substantially horizontal at the water supply position, and the top surface 381a of the second cell wall <NUM> may be disposed below the first cell wall 321a to be inclined with respect to the bottom surface 321d of the first cell wall 321a.

In the state of <FIG>, the circumferential wall <NUM> may surround the first cell wall 321a. Also, an upper end of the circumferential wall <NUM> may be positioned higher than the bottom surface 321d of the first cell wall 321a.

At the ice making position (see <FIG>), the top surface 381a of the second cell wall <NUM> may contact at least a portion of the bottom surface 321d of the first cell wall 321a.

The angle formed between the top surface 381a of the second tray <NUM> and the bottom surface 321d of the first tray <NUM> at the ice making position is less than that between the top surface 382a of the second tray and the bottom surface 321d of the first tray at the water supply position.

At the ice making position, the top surface 381a of the second cell wall <NUM> may contact all of the bottom surface 321d of the first cell wall 321a. At the ice making position, the top surface 381a of the second cell wall <NUM> and the bottom surface 321d of the first cell wall 321a may be disposed to be substantially parallel to each other.

According to the invention, the water supply position of the second tray <NUM> and the ice making position are different from each other. This is done for uniformly distributing the water to the plurality of ice making cells 320a without providing a water passage for the first tray <NUM> and/or the second tray <NUM> when the ice maker <NUM> includes the plurality of ice making cells 320a.

If the ice maker <NUM> includes the plurality of ice making cells 320a, when the water passage is provided in the first tray <NUM> and/or the second tray <NUM>, the water supplied into the ice maker <NUM> may be distributed to the plurality of ice making cells 320a along the water passage.

However, when the water is distributed to the plurality of ice making cells 320a, the water also exists in the water passage, and when ice is made in this state, the ice made in the ice making cells 320a may be connected by the ice made in the water passage portion.

In this case, there is a possibility that the ice sticks to each other even after the completion of the ice, and even if the ice is separated from each other, some of the plurality of ice includes ice made in a portion of the water passage. Thus, the ice may have a shape different from that of the ice making cell.

However, like this embodiment, when the second tray <NUM> is spaced apart from the first tray <NUM> at the water supply position, water dropping to the second tray <NUM> may be uniformly distributed to the plurality of second cells 320c of the second tray <NUM>.

For example, the first tray <NUM> may include a communication hole 321e. When the first tray <NUM> includes one first cell 320b, the first tray <NUM> may include one communication hole 321e. When the first tray <NUM> includes a plurality of first cells 320b, the first tray <NUM> may include a plurality of communication holes 321e. The water supply part <NUM> may supply water to one communication hole 321e of the plurality of communication holes 321e. In this case, the water supplied through the one communication hole 321e drops to the second tray <NUM> after passing through the first tray <NUM>.

In the water supply process, water may drop into any one of the second cells 320c of the plurality of second cells 320c of the second tray <NUM>. The water supplied to one of the second cells 320c may overflow from the one of the second cells 320c.

In this embodiment, since the top surface 381a of the second tray <NUM> is spaced apart from the bottom surface 321d of the first tray <NUM>, the water overflowed from any one of the second cells 320c may move to the adjacent other second ell 320c along the top surface 381a of the second tray <NUM>. Therefore, the plurality of second cells 320c of the second tray <NUM> may be filled with water.

Also, in the state in which water supply is completed, a portion of the water supplied may be filled in the second cell 320c, and the other portion of the water supplied may be filled in the space between the first tray <NUM> and the second tray <NUM>.

At the water supply position, according to a volume of the ice making cell 320a, the water when the water supply is completed may be disposed only in the space between the first tray <NUM> and the second tray <NUM> or may also be disposed in the space between the second tray <NUM> and the first tray <NUM> (see <FIG>).

When the second tray <NUM> move from the water supply position to the ice making position, the water in the space between the first tray <NUM> and the second tray <NUM> may be uniformly distributed to the plurality of first cells 320b.

When water passages are provided in the first tray <NUM> and/or the second tray <NUM>, ice made in the ice making cell 320a may also be made in a portion of the water passage.

In this case, when the controller of the refrigerator controls one or more of the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater to vary according to the mass per unit height of the water in the ice making cell 320a, one or more of the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater may be abruptly changed several times or more in the portion at which the water passage is provided.

This is because the mass per unit height of the water increases more than several times in the portion at which the water passage is provided. In this case, reliability problems of components may occur, and expensive components having large maximum output and minimum output ranges may be used, which may be disadvantageous in terms of power consumption and component costs. As a result, the present invention may require the technique related to the aforementioned ice making position to make the transparent ice.

<FIG> is a control block diagram of a refrigerator according to an embodiment of the present invention, <FIG> is an exploded perspective view of a driver according to an embodiment of the present invention, and <FIG> is a plan view illustrating an internal configuration of the driver. <FIG> is a view illustrating a cam and an operation lever of the driver, and <FIG> is a view illustrating a position relationship between a hall sensor and a magnet depending on rotation of the cam.

(a) of <FIG> illustrates a state in which the hall sensor and the magnet are aligned at the first position of a magnet lever, and (b) of <FIG> illustrates a state in which the hall sensor and the magnet are not aligned at the first position of the magnet lever.

<FIG>, the refrigerator according to this embodiment may include an air supply part <NUM> supplying cold air to the freezing compartment <NUM> (or the ice making cell). The cold air supply part <NUM> may supply cold air to the freezing compartment <NUM> using a refrigerant cycle.

For example, the cold air supply part <NUM> may include a compressor compressing the refrigerant. A temperature of the cold air supplied to the freezing compartment <NUM> may vary according to the output (or frequency) of the compressor. Alternatively, the cold air supply part <NUM> may include a fan blowing air to an evaporator. An amount of cold air supplied to the freezing compartment <NUM> may vary according to the output (or rotation rate) of the fan. Alternatively, the cold air supply part <NUM> may include a refrigerant valve controlling an amount of refrigerant flowing through the refrigerant cycle. An amount of refrigerant flowing through the refrigerant cycle may vary by adjusting an opening degree by the refrigerant valve, and thus, the temperature of the cold air supplied to the freezing compartment <NUM> may vary.

Therefore, in this embodiment, the cold air supply part <NUM> may include one or more of the compressor, the fan, and the refrigerant valve.

The refrigerator according to this embodiment may further include a controller <NUM> that controls the cold air supply part <NUM>. Also, the refrigerator may further include a water supply valve <NUM> controlling an amount of water supplied through the water supply part <NUM>.

The controller <NUM> may control a portion or all of the ice separation heater <NUM>, the transparent ice heater <NUM>, the driver <NUM>, the cold air supply part <NUM>, and the water supply valve <NUM>.

In this embodiment, when the ice maker <NUM> includes both the ice separation heater <NUM> and the transparent ice heater <NUM>, an output of the ice separation heater <NUM> and an output of the transparent ice heater <NUM> may be different from each other. When the outputs of the ice separation heater <NUM> and the transparent ice heater <NUM> are different from each other, an output terminal of the ice separation heater <NUM> and an output terminal of the transparent ice heater <NUM> may be provided in different shapes, incorrect connection of the two output terminals may be prevented.

Although not limited, the output of the ice separation heater <NUM> may be set larger than that of the transparent ice heater <NUM>. Accordingly, ice may be quickly separated from the first tray <NUM> by the ice separation heater <NUM>.

In this embodiment, when the ice separation heater <NUM> is not provided, the transparent ice heater <NUM> may be disposed at a position adjacent to the second tray <NUM> described above or be disposed at a position adjacent to the first tray <NUM>.

The refrigerator may further include a first temperature sensor <NUM> (or a temperature sensor in the refrigerator) that detects a temperature of the freezing compartment <NUM>.

The controller <NUM> may control the cold air supply part <NUM> based on the temperature detected by the first temperature sensor <NUM>. The controller <NUM> may determine whether the ice making is completed based on the temperature detected by the second temperature sensor <NUM>.

The refrigerator may further include a full ice detection part <NUM> for detecting full ice of the ice bin <NUM>.

The ice detection part <NUM> may include, for example, the full ice detection lever <NUM>, a magnet provided in the driver <NUM>, and a hall sensor detecting the magnet.

The driver <NUM> may include an operation lever <NUM> that in organically interlocked by a motor <NUM>, a cam <NUM> rotating by the motor <NUM>, and a cam surface for the detection lever of the cam <NUM>.

The driver <NUM> may further include a lever coupling part <NUM> that rotates (swings) the full ice detection lever <NUM> in the left and right direction while rotating by the operation lever <NUM>. The driver <NUM> may include a magnet lever <NUM>, which is organically interlocked along the cam surface for the magnet of the cam <NUM>, the motor <NUM>, the cam <NUM>, the operation lever <NUM>, and the lever coupling part <NUM>, and a case in which the magnet lever <NUM> is embedded.

The case may include a first case <NUM> in which the motor <NUM>, the cam <NUM>, the operation lever <NUM>, the lever coupling part <NUM>, and the magnet lever <NUM> are embedded, and a second case <NUM> that covers the first case <NUM>. The motor <NUM> generates power for rotating the cam <NUM>.

The driver <NUM> may further include a control panel <NUM> coupled to an inner side of the first case <NUM>. The motor <NUM> may be connected to the control panel <NUM>.

A hall sensor <NUM> may be provided on the control panel <NUM>. The hall sensor <NUM> may output a first signal and a second signal according to a position relative to the magnet lever <NUM>.

As illustrated in <FIG>, the cam <NUM> may include a coupling part <NUM> to which the rotation arm <NUM> is coupled. The coupling part <NUM> serves as a rotation shaft of the cam <NUM>.

The cam <NUM> may include a gear <NUM> to transmit power to the motor <NUM>. The gear <NUM> may be formed on an outer circumferential surface of the cam <NUM>. The cam <NUM> may include a cam surface <NUM> for the detection lever and a cam surface <NUM> for the magnet. That is, the cam <NUM> forms a path through which the levers <NUM> and <NUM> move. A cam groove 4833a for the detection lever, which rotates the full ice detection lever <NUM> by lowering the operation lever <NUM> is formed in the cam surface <NUM> for the detection lever.

A cam groove 4834a for the magnet, which lowers the magnet lever <NUM> so that the magnet lever <NUM> and the hall sensor <NUM> are separated from each other is formed in the cam surface <NUM> for the magnet.

A reduction gear <NUM> that reduces rotational force of the motor <NUM> to transmit the rotational force to the cam <NUM> may be provided between the cam <NUM> and the motor <NUM>. The reduction gear <NUM> may include a first reduction gear <NUM> connected to the motor <NUM> to transmit power, a second reduction gear <NUM> engaged with the first reduction gear <NUM>, and a third reduction gear <NUM> connecting the second reduction gear <NUM> to the cam <NUM> to transmit the power.

One end of the operation lever <NUM> is fitted and coupled to the rotation shaft of the third reduction gear <NUM> so as to be freely rotatable, and a gear <NUM> formed at the other end of the operation lever <NUM> is connected to the lever coupling part <NUM> so as to transmit the power. That is, when the operation lever <NUM> move, the lever coupling part <NUM> rotates.

The lever coupling part <NUM> has one end rotatably connected to the operation lever <NUM> inside the case and the other end protruding to the outside of the case so as to be coupled to the full ice detection lever <NUM>.

The magnet lever <NUM> may include a central portion rotatably provided on the case, an end that is organically interlocked along the cam surface <NUM> for the magnet of the cam <NUM>, and a magnet <NUM> that is aligned with the hall sensor <NUM> or spaced apart from the hall sensor <NUM>.

As illustrated in (a) of <FIG>, when the magnet <NUM> is aligned with the hall sensor <NUM>, any one of the first signal and the second signal may be output from the hall sensor <NUM>.

As illustrated in (b) of <FIG>, when the magnet <NUM> is out of the position facing the hall sensor <NUM>, the other signal of the first signal and the second signal is output from the hall sensor <NUM>.

A blocking member <NUM> that selectively blocks the cam groove 4833a for the detection lever so that the operation lever <NUM> moving along the cam surface <NUM> for the detection lever is not inserted into the cam groove 4833a for the detection lever when the full ice detection lever <NUM> returns to its original position may be provided on the rotation shaft of the cam <NUM>.

That is, the blocking member <NUM> may include a coupling part <NUM> rotatably coupled to the rotation shaft of the cam <NUM> and a hook groove <NUM> formed in one side of the coupling part <NUM> and coupled to the protrusion <NUM> formed on the bottom surface of the case to restrict a rotation angle of the coupling part <NUM>.

The blocking member <NUM> may further include a support protrusion <NUM> that is provided outside the coupling part <NUM> to restrict an operation of the operation lever <NUM> so that the operation lever <NUM> is not inserted into the cam groove 4833a for the detection lever while being supported on or separated from the operation lever <NUM> when the cam gear rotates in the forward or reverse direction.

The driver <NUM> may further include an elastic member that provides elastic force so that the lever coupling part <NUM> rotates in one direction. One end of the elastic member may be connected to the lever coupling part <NUM>, and the other end may be fixed to the case.

A protrusion 4833b may be provided between the cam surface <NUM> for the detection lever of the cam <NUM> and the cam groove 4833a.

In this embodiment, the cam surface <NUM> for the detection lever may be designed, for example, so that, in the process in which the second tray <NUM> (or the full ice detection lever <NUM>) moves from the ice making position to the water supply position, a first signal is output from the sensor <NUM>, and when the second tray <NUM> moves to the water supply position, a second signal is output from the sensor <NUM>.

Also, the cam surface <NUM> for the detection lever may be designed, for example, so that, in the process in which the second tray <NUM> moves from the water supply position to the ice making position, a second signal is output from the sensor <NUM>, and when the second tray <NUM> moves to the full ice detection position, a first signal is output from the sensor <NUM>.

Also, the cam surface <NUM> for the detection lever may be designed, for example, in the process in which the second tray <NUM> moves from the full ice detection position to the ice separation position, a second signal is output from the sensor <NUM>, and when the second tray <NUM> moves to the ice separation position, a first signal is output from the sensor <NUM>.

The controller <NUM> may determine that the ice bin is not full when, for example, the first signal is output for a predetermined time from the hall sensor <NUM> after the second tray <NUM> passes through the water supply position in the ice separation process.

On the other hand, the controller <NUM> may determine that the ice bin is full when the first signal is not output from the sensor <NUM> for a reference time after the second tray <NUM> passes through the water supply position, or the second signal is continuously output from the hall sensor <NUM> for the reference time in the ice separation process.

As another example, the full ice detection part <NUM> may include a light emitting part and a light receiving part, which are provided in the ice bin <NUM>. In this case, the full ice detection lever <NUM> may be omitted. When light irradiated from the light emitting part reaches the light receiving part, it may be determined as no full ice. If the light irradiated from the light emitting part does not reach the light receiving part, it may be determined as full ice. In this case, the light emitting part and the light receiving part may be provided in the ice maker. In this case, the light emitting part and the light receiving part may be disposed in the ice bin.

As described above, since the type of signals and time, which are output from the hall sensor <NUM> for each position of the second tray <NUM> are different from each other, the controller <NUM> may accurately determine the current position of the second tray <NUM>.

When the full ice detection lever <NUM> is disposed at the full ice detection position, the second tray <NUM> may also be described as being disposed at the full ice detection position.

<FIG> and <FIG> are flowcharts for explaining a process of making ice in the ice maker according to an embodiment of the present invention.

<FIG> is a view for explaining a height reference depending on a relative position of the transparent heater with respect to the ice making cell, and <FIG> is a view for explaining an output of the transparent heater per unit height of water within the ice making cell.

<FIG> is a view illustrating movement of a second tray when full ice is not detected in an ice separation process, <FIG> is a view illustrating movement of the second tray when the full ice is detected in the ice separation process, and <FIG> is a view illustrating movement of the second tray when full ice is detected again after the full ice is detected.

(a) of <FIG> illustrates a state in which the second tray moves to the ice making position, (b) of <FIG> illustrates a state in which the second tray and the full ice detection lever move to the full ice detection position, and (c) of <FIG> illustrates a state in which the second tray moves to the ice separation position. (d) of <FIG> illustrates a state in which the second tray moves to the water supply position.

Referring to <FIG>, to make ice in the ice maker <NUM>, the controller <NUM> moves the second tray <NUM> to a water supply position (S1).

In this specification, a direction in which the second tray <NUM> moves from the ice making position in (a) of <FIG> to the ice separation position in (c) of <FIG> may be referred to as forward movement (or forward rotation). On the other hand, the direction from the ice separation position in (c) of <FIG> to the water supply position in (d) of <FIG> may be referred to as reverse movement (or reverse rotation).

When it is detected that the second tray <NUM> move to the water supply position, the controller <NUM> stops an operation of the driver <NUM>.

In the state in which the second tray <NUM> moves to the water supply position, the water supply starts (S2). For the water supply, the controller <NUM> turns on the water supply valve <NUM>, and when it is determined that a first water supply amount is supplied, the controller <NUM> may turn off the water supply valve <NUM>. For example, in the process of supplying water, when a pulse is outputted from a flow sensor (not shown), and the outputted pulse reaches a reference pulse, it may be determined that water as much as the water supply amount is supplied.

After the water supply is completed, the controller <NUM> controls the driver <NUM> to allow the second tray <NUM> to move to the ice making position (S3). For example, the controller <NUM> may control the driver <NUM> to allow the second tray <NUM> to move from the water supply position in the reverse direction. When the second tray <NUM> move in the reverse direction, the top surface 381a of the second tray <NUM> comes close to the bottom surface 321e of the first tray <NUM>. Then, water between the top surface 381a of the second tray <NUM> and the bottom surface 321e of the first tray <NUM> is divided into each of the plurality of second cells 320c and then is distributed. When the top surface 381a of the second tray <NUM> and the bottom surface 321e of the first tray <NUM> contact each other, water is filled in the first cell 320b.

The movement to the ice making position of the second tray <NUM> is detected by a sensor, and when it is detected that the second tray <NUM> moves to the ice making position, the controller <NUM> stops the driver <NUM>.

In the state in which the second tray <NUM> moves to the ice making position, ice making is started (S4). For example, the ice making may be started when the second tray <NUM> reaches the ice making position. Alternatively, when the second tray <NUM> reaches the ice making position, and the water supply time elapses, the ice making may be started.

When ice making is started, the controller <NUM> may control the cold air supply part <NUM> to supply cold air to the ice making cell 320a.

After the ice making is started, the controller <NUM> may control the transparent ice heater <NUM> to be turned on in at least partial sections of the cold air supply part <NUM> supplying the cold air to the ice making cell 320a.

When the transparent ice heater <NUM> is turned on, since the heat of the transparent ice heater <NUM> is transferred to the ice making cell 320a, the ice making rate of the ice making cell 320a may be delayed.

According to this embodiment, the ice making rate may be delayed so that the bubbles dissolved in the water inside the ice making cell 320a move from the portion at which ice is made toward the liquid water by the heat of the transparent ice heater <NUM> to make the transparent ice in the ice maker <NUM>.

In the ice making process, the controller <NUM> may determine whether the turn-on condition of the transparent ice heater <NUM> is satisfied (S5).

In this embodiment, the transparent ice heater <NUM> is not turned on immediately after the ice making is started, and the transparent ice heater <NUM> may be turned on only when the turn-on condition of the transparent ice heater <NUM> is satisfied (S6).

Generally, the water supplied to the ice making cell 320a may be water having normal temperature or water having a temperature lower than the normal temperature. The temperature of the water supplied is higher than a freezing point of water. Thus, after the water supply, the temperature of the water is lowered by the cold air, and when the temperature of the water reaches the freezing point of the water, the water is changed into ice.

In this embodiment, the transparent ice heater <NUM> may not be turned on until the water is phase-changed into ice.

If the transparent ice heater <NUM> is turned on before the temperature of the water supplied to the ice making cell 320a reaches the freezing point, the speed at which the temperature of the water reaches the freezing point by the heat of the transparent ice heater <NUM> is slow. As a result, the starting of the ice making may be delayed.

The transparency of the ice may vary depending on the presence of the air bubbles in the portion at which ice is made after the ice making is started. If heat is supplied to the ice making cell 320a before the ice is made, the transparent ice heater <NUM> may operate regardless of the transparency of the ice.

Thus, according to this embodiment, after the turn-on condition of the transparent ice heater <NUM> is satisfied, when the transparent ice heater <NUM> is turned on, power consumption due to the unnecessary operation of the transparent ice heater <NUM> may be prevented.

Alternatively, even if the transparent ice heater <NUM> is turned on immediately after the start of ice making, since the transparency is not affected, it is also possible to turn on the transparent ice heater <NUM> after the start of the ice making.

In this embodiment, the controller <NUM> may determine that the turn-on condition of the transparent ice heater <NUM> is satisfied when a predetermined time elapses from the set specific time point. The specific time point may be set to at least one of the time points before the transparent ice heater <NUM> is turned on. For example, the specific time point may be set to a time point at which the cold air supply part <NUM> starts to supply cooling power for the ice making, a time point at which the second tray <NUM> reaches the ice making position, a time point at which the water supply is completed, and the like.

Alternatively, the controller <NUM> determines that the turn-on condition of the transparent ice heater <NUM> is satisfied when a temperature detected by the second temperature sensor <NUM> reaches a turn-on reference temperature.

For example, the turn-on reference temperature may be a temperature for determining that water starts to freeze at the uppermost side (communication hole-side) of the ice making cell 320a.

When a portion of the water is frozen in the ice making cell 320a, the temperature of the ice in the ice making cell 320a is below zero.

The temperature of the first tray <NUM> may be higher than the temperature of the ice in the ice making cell 320a.

Alternatively, although water exists in the ice making cell 320a, after the ice starts to be made in the ice making cell 320a, the temperature detected by the second temperature sensor <NUM> may be below zero.

Thus, to determine that making of ice is started in the ice making cell 320a on the basis of the temperature detected by the second temperature sensor <NUM>, the turn-on reference temperature may be set to the below-zero temperature.

That is, when the temperature detected by the second temperature sensor <NUM> reaches the turn-on reference temperature, since the turn-on reference temperature is below zero, the ice temperature of the ice making cell 320a is below zero, i.e., lower than the below reference temperature. Therefore, it may be indirectly determined that ice is made in the ice making cell 320a.

As described above, when the transparent ice heater <NUM> is not used, the heat of the transparent ice heater <NUM> is transferred into the ice making cell 320a.

In this embodiment, when the second tray <NUM> is disposed below the first tray <NUM>, the transparent ice heater <NUM> is disposed to supply the heat to the second tray <NUM>, the ice may be made from an upper side of the ice making cell 320a.

In this embodiment, since ice is made from the upper side in the ice making cell 320a, the bubbles move downward from the portion at which the ice is made in the ice making cell 320a toward the liquid water.

Since density of water is greater than that of ice, water or bubbles may be convex in the ice making cell 320a, and the bubbles may move to the transparent ice heater <NUM>.

In this embodiment, the mass (or volume) per unit height of water in the ice making cell 320a may be the same or different according to the shape of the ice making cell 320a. For example, when the ice making cell 320a is a rectangular parallelepiped, the mass (or volume) per unit height of water in the ice making cell 320a is the same. On the other hand, when the ice making cell 320a has a shape such as a sphere, an inverted triangle, a crescent moon, etc., the mass (or volume) per unit height of water is different.

If the cooling power of the cold air supply part <NUM> is constant, if the heating amount of the transparent ice heater <NUM> is the same, since the mass per unit height of water in the ice making cell 320a is different, an ice making rate per unit height may be different.

For example, if the mass per unit height of water is small, the ice making rate is high, whereas if the mass per unit height of water is high, the ice making rate is slow.

As a result, the ice making rate per unit height of water is not constant, and thus, the transparency of the ice may vary according to the unit height. In particular, when ice is made at a high rate, the bubbles may not move from the ice to the water, and the ice may contain the bubbles to lower the transparency.

That is, the more the variation in ice making rate per unit height of water decreases, the more the variation in transparency per unit height of made ice may decrease.

Therefore, in this embodiment, the controller <NUM> may control the cooling power and/or the heating amount so that the cooling power of the cold air supply part <NUM> and/or the heating amount of the transparent ice heater <NUM> is variable according to the mass per unit height of the water of the ice making cell 320a.

In this specification, the variable of the cooling power of the cold air supply part <NUM> may include one or more of a variable output of the compressor, a variable output of the fan, and a variable opening degree of the refrigerant valve.

Also, in this specification, the variation in the heating amount of the transparent ice heater <NUM> may represent varying the output of the transparent ice heater <NUM> or varying the duty of the transparent ice heater <NUM>.

In this case, the duty of the transparent ice heater <NUM> represents a ratio of the turn-on time and the turn-off time of the transparent ice heater <NUM> in one cycle, or a ratio of the turn-on time and the turn-off time of the transparent ice heater <NUM> in one cycle.

In this specification, a reference of the unit height of water in the ice making cell 320a may vary according to a relative position of the ice making cell 320a and the transparent ice heater <NUM>.

For example, as shown in (a) of <FIG>, the transparent ice heater <NUM> at the bottom surface of the ice making cell 320a may be disposed to have the same height.

In this case, a line connecting the transparent ice heater <NUM> is a horizontal line, and a line extending in a direction perpendicular to the horizontal line serves as a reference for the unit height of the water of the ice making cell 320a.

In the case of (a) of <FIG>, ice is made from the uppermost side of the ice making cell 320a and then is grown. On the other hand, as illustrated in (b) of <FIG>, the transparent ice heater <NUM> at the bottom surface of the ice making cell 320a may be disposed to have different heights.

In this case, since heat is supplied to the ice making cell 320a at different heights of the ice making cell 320a, ice is made with a pattern different from that of (a) of <FIG>.

For example, in (b) of <FIG>, ice may be made at a position spaced apart from the uppermost side to the left side of the ice making cell 320a, and the ice may be grown to a right lower side at which the transparent ice heater <NUM> is disposed.

Accordingly, in (b) of <FIG>, a line (reference line) perpendicular to the line connecting two points of the transparent ice heater <NUM> serves as a reference for the unit height of water of the ice making cell 320a. The reference line of (b) of <FIG> is inclined at a predetermined angle from the vertical line.

<FIG> illustrates a unit height division of water and an output amount of transparent ice heater per unit height when the transparent ice heater is disposed as shown in (a) of <FIG>.

Hereinafter, an example of controlling an output of the transparent ice heater so that the ice making rate is constant for each unit height of water will be described.

Referring to <FIG>, when the ice making cell 320a is formed, for example, in a spherical shape, the mass per unit height of water in the ice making cell 320a increases from the upper side to the lower side to reach the maximum and then decreases again.

For example, the water (or the ice making cell itself) in the spherical ice making cell 320a having a diameter of about <NUM> is divided into nine sections (section A to section I) by <NUM> height (unit height). Here, it is noted that there is no limitation on the size of the unit height and the number of divided sections.

When the water in the ice making cell 320a is divided into unit heights, the height of each section to be divided is equal to the section A to the section H, and the section I is lower than the remaining sections. Alternatively, the unit heights of all divided sections may be the same depending on the diameter of the ice making cell 320a and the number of divided sections.

Among the plurality of sections, the section E is a section in which the mass of unit height of water is maximum. For example, in the section in which the mass per unit height of water is maximum, when the ice making cell 320a has spherical shape, a diameter of the ice making cell 320a, a horizontal cross-sectional area of the ice making cell 320a, or a circumference of the ice are maximized.

As described above, when assuming that the cooling power of the cold air supply part <NUM> is constant, and the output of the transparent ice heater <NUM> is constant, the ice making rate in section E is the lowest, the ice making rate in the sections A and I is the fastest.

In this case, since the ice making rate varies for the height, the transparency of the ice may vary for the height. In a specific section, the ice making rate may be too fast to contain bubbles, thereby lowering the transparency.

Therefore, in this embodiment, the output of the transparent ice heater <NUM> may be controlled so that the ice making rate for each unit height is the same or similar while the bubbles move from the portion at which ice is made to the water in the ice making process.

Specifically, since the mass of the section E is the largest, the output W5 of the transparent ice heater <NUM> in the section E may be set to a minimum value. Since the volume of the section D is less than that of the section E, the volume of the ice may be reduced as the volume decreases, and thus it is necessary to delay the ice making rate. Thus, an output W6 of the transparent ice heater <NUM> in the section D may be set to a value greater than an output W5 of the transparent ice heater <NUM> in the section E.

Since the volume in the section C is less than that in the section D by the same reason, an output W3 of the transparent ice heater <NUM> in the section C may be set to a value greater than the output W4 of the transparent ice heater <NUM> in the section D.

Since the volume in the section B is less than that in the section C, an output W2 of the transparent ice heater <NUM> in the section B may be set to a value greater than the output W3 of the transparent ice heater <NUM> in the section C. Also, since the volume in the section A is less than that in the section B, an output W1 of the transparent ice heater <NUM> in the section A may be set to a value greater than the output W2 of the transparent ice heater <NUM> in the section B. For the same reason, since the mass per unit height decreases toward the lower side in the section E, the output of the transparent ice heater <NUM> may increase as the lower side in the section E (see W6, W7, W8, and W9).

Thus, according to an output variation pattern of the transparent ice heater <NUM>, the output of the transparent ice heater <NUM> is gradually reduced from the first section to the intermediate section after the transparent ice heater <NUM> is initially turned on.

The output of the transparent ice heater <NUM> may be minimum in the intermediate section in which the mass of unit height of water is minimum. The output of the transparent ice heater <NUM> may again increase step by step from the next section of the intermediate section.

The transparency of the ice may be uniform for each unit height, and the bubbles may be collected in the lowermost section by the output control of the transparent ice heater <NUM>. Thus, when viewed on the ice as a whole, the bubbles may be collected in the localized portion, and the remaining portion may become totally transparent.

As described above, even if the ice making cell 320a does not have the spherical shape, the transparent ice may be made when the output of the transparent ice heater <NUM> varies according to the mass for each unit height of water in the ice making cell 320a.

The heating amount of the transparent ice heater <NUM> when the mass for each unit height of water is large may be less than that of the transparent ice heater <NUM> when the mass for each unit height of water is small.

For example, while maintaining the same cooling power of the cold air supply part <NUM>, the heating amount of the transparent ice heater <NUM> may vary so as to be inversely proportional to the mass per unit height of water.

Also, it is possible to make the transparent ice by varying the cooling power of the cold air supply part <NUM> according to the mass per unit height of water.

For example, when the mass per unit height of water is large, the cold force of the cold air supply part <NUM> may increase, and when the mass per unit height is small, the cold force of the cold air supply part <NUM> may decrease.

For example, while maintaining a constant heating amount of the transparent ice heater <NUM>, the cooling power of the cold air supply part <NUM> may vary to be proportional to the mass per unit height of water.

Referring to the variable cooling power pattern of the cold air supply part <NUM> in the case of making the spherical ice, the cooling power of the cold air supply part <NUM> from the initial section to the intermediate section during the ice making process may increase step by step.

The cooling power of the cold air supply part <NUM> may be maximum in the intermediate section in which the mass for each unit height of water is minimum. The cooling power of the cold air supply part <NUM> may be reduced again step by step from the next section of the intermediate section.

Alternatively, the transparent ice may be made by varying the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater <NUM> according to the mass for each unit height of water.

For example, the heating power of the transparent ice heater <NUM> may vary so that the cooling power of the cold air supply part <NUM> is proportional to the mass per unit height of water and inversely proportional to the mass for each unit height of water.

According to this embodiment, when one or more of the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater <NUM> are controlled according to the mass per unit height of water, the ice making rate per unit height of water may be substantially the same or may be maintained within a predetermined range.

The controller <NUM> may determine whether the ice making is completed based on the temperature detected by the second temperature sensor <NUM> (S8). When it is determined that the ice making is completed, the controller <NUM> may turn off the transparent ice heater <NUM> (S9).

For example, when the temperature detected by the second temperature sensor <NUM> reaches a first reference temperature, the controller <NUM> may determine that the ice making is completed to turn off the transparent ice heater <NUM>.

In this case, since a distance between the second temperature sensor <NUM> and each ice making cell 320a is different, in order to determine that the ice making is completed in all the ice making cells 320a, the controller <NUM> may perform the ice separation after a certain amount of time, at which it is determined that ice making is completed, has passed or when the temperature detected by the second temperature sensor <NUM> reaches a second reference temperature lower than the first reference temperature.

Of course, when the transparent ice heater <NUM> is turned off, it is also possible to start the ice separation immediately.

When the ice making is completed, the controller <NUM> operates one or more of the ice maker heater <NUM> and the transparent ice heater <NUM> (S10).

When one or more of the ice separation heater <NUM> and the transparent ice heater <NUM> are turned on, heat of the heaters <NUM> and <NUM> is transferred to one or more of the first tray <NUM> and the second tray <NUM> so that the ice is separated from the surfaces (inner surfaces) of one or more of the first tray <NUM> and the second tray <NUM>.

Also, the heat of the heaters <NUM> and <NUM> is transferred to the contact surface of the first tray <NUM> and the second tray <NUM>, and thus, the bottom surface 321d of the first tray and the top surface 381a of the second tray <NUM> may be in a state capable of being separated from each other.

When one or more of the ice separation heater <NUM> and the transparent ice heater <NUM> operate for a predetermined time, or when the temperature detected by the second temperature sensor <NUM> is equal to or higher than a turn-off reference temperature, the controller <NUM> is turned off the heaters <NUM> and <NUM>, which are turned on.

Although not limited, the turn-off reference temperature may be set to above zero temperature.

For the ice separation, the controller <NUM> operates the driver <NUM> to allow the second tray <NUM> to move in the forward direction (S12).

As illustrated in <FIG>, when the second tray <NUM> move in the forward direction, the second tray <NUM> is spaced apart from the first tray <NUM>.

The moving force of the second tray <NUM> is transmitted to the first pusher <NUM> by the pusher link <NUM>. Then, the first pusher <NUM> descends along the guide slot <NUM>, and the extension part <NUM> passes through the communication hole 321e to press the ice in the ice making cell 320a.

In this embodiment, ice may be separated from the first tray <NUM> before the extension part <NUM> presses the ice in the ice making process. That is, ice may be separated from the surface of the first tray <NUM> by the heater that is turned on. In this case, the ice may move together with the second tray <NUM> while the ice is supported by the second tray <NUM>.

For another example, even when the heat of the heater is applied to the first tray <NUM>, the ice may not be separated from the surface of the first tray <NUM>.

Therefore, when the second tray <NUM> moves in the forward direction, there is possibility that the ice is separated from the second tray <NUM> in a state in which the ice contacts the first tray <NUM>.

In this state, in the process of moving the second tray <NUM>, the extension part <NUM> passing through the communication hole 320e may press the ice contacting the first tray <NUM>, and thus, the ice may be separated from the tray <NUM>. The ice separated from the first tray <NUM> may be supported again by the second tray <NUM>.

When the ice moves together with the second tray <NUM> while the ice is supported by the second tray <NUM>, the ice may be separated from the tray <NUM> by its own weight even if no external force is applied to the second tray <NUM>.

While the second tray <NUM> moves, even if the ice does not fall from the second tray <NUM> by its own weight, when the second tray <NUM> is pressed by the second pusher <NUM> as illustrated in <FIG>, the ice may be separated from the second tray <NUM> to fall downward.

Particularly, while the second tray <NUM> moves, the second tray <NUM> may contact the extension part <NUM> of the second pusher <NUM>.

When the second tray <NUM> continuously moves in the forward direction, the extension part <NUM> may press the second tray <NUM> to deform the second tray <NUM> and the extension part <NUM>. Thus, the pressing force of the extension part <NUM> may be transferred to the ice so that the ice is separated from the surface of the second tray <NUM>.

The ice separated from the surface of the second tray <NUM> may drop downward and be stored in the ice bin <NUM>.

In this embodiment, in the state in which the second tray <NUM> move to the ice separation position, the second tray <NUM> may be pressed by the second pusher <NUM> and thus be changed in shape.

Whether the ice bin <NUM> is full may be detected while the second tray <NUM> moves from the ice making position to the ice separation position (S12).

As an example, while the full ice detection lever <NUM> rotates together with the second tray <NUM>, when the full ice detection lever <NUM> moves to the full ice detection position, the first signal is output from the hall sensor <NUM> as described above, and thus, it may be determined that the ice bin <NUM> is not full.

In the state in which the full ice detection lever <NUM> moves to the full ice detection position, the first body <NUM> of the full ice detection lever <NUM> is disposed in the ice bin <NUM>. In this case, a maximum distance from an upper end of the ice bin <NUM> to the first body <NUM> may be set to be less than a radius of ice generated in the ice making cell 320a. This means that the first body <NUM> lifts the ice stored in the ice bin <NUM> while the full ice detection lever <NUM> moves to the full ice detection position so that the ice is discharged from the ice bin <NUM>.

Also, the first body <NUM> may be disposed lower than the second tray <NUM> and be spaced apart from the second tray <NUM> in the process of rotating the full ice detection lever <NUM> so that an interference between the full ice detection lever <NUM> and the second tray <NUM> is prevented.

On the other hand, in the process of rotating the full ice detection lever <NUM>, before the full ice detection lever <NUM> moves to the full ice detection position, if the full ice detection lever <NUM> interferes with ice, the first signal is not output from the hall sensor <NUM>.

Thus, the controller <NUM> may determine that the ice bin is full when the first signal is not output from the hall sensor <NUM> for a reference time, or the second signal is continuously output from the sensor <NUM> for the reference time in the ice separation process.

If it is determined that the ice bin <NUM> is not full, the controller <NUM> controls the driver <NUM> to allow the second tray <NUM> to move to the ice separation position as illustrated in (c) of <FIG>.

As described above, when the second tray <NUM> moves to the ice separation position, ice may be separated from the second tray <NUM>. After the ice is separated from the second tray <NUM>, the controller <NUM> controls the driver <NUM> to allow the second tray <NUM> to move in the reverse direction (S14). Then, the second tray <NUM> moves from the ice separation position to the water supply position (S1).

When the second tray <NUM> moves to the water supply position, the controller <NUM> stops the driver <NUM>. When the second tray <NUM> is spaced apart from the extension part <NUM> while the second tray <NUM> moves in the reverse direction, the deformed second tray <NUM> may be restored to its original shape. In the reverse movement of the second tray <NUM>, the moving force of the second tray <NUM> is transmitted to the first pusher <NUM> by the pusher link <NUM>, and thus, the first pusher <NUM> ascends, and the extension part <NUM> is removed from the ice making cell 320a.

As a result of the determination in operation S12, if it is determined that the ice bin <NUM> is full, the controller <NUM> controls the driver <NUM> so that the second tray <NUM> moves to the ice separation position for separating ice (S <NUM>).

That is, according to the invention, even if the full ice is initially detected by the full ice detection part, the ice is separated from the second tray <NUM>.

Then, the controller <NUM> controls the driver <NUM> so that the second tray <NUM> moves in the reverse direction to move to the water supply position (S <NUM>).

The controller <NUM> may determine whether a set time elapses while the second tray <NUM> moves to the water supply position (S <NUM>).

When the set time elapses in the state in which the second tray <NUM> moves to the water supply position, whether the ice bin is full may be detected again (S19).

For example, the controller <NUM> controls the driver <NUM> so that the second tray <NUM> moves from the water supply position to the full ice detection position.

That is, in this embodiment, after the second tray <NUM> moves to the ice separation position for separating ice, the detection of the full ice may be repetitively performed at a predetermined period.

As a result of determination in operation S19, when the full ice is detected, the second tray <NUM> moves to the water supply position to stand by.

On the other hand, as a result of the determination in operation S <NUM>, if the full ice is not detected, the second tray <NUM> may move from the full ice detection position to the ice separation position and then to the water supply position. Alternatively, the second tray <NUM> may moves in the reverse direction from the full ice position and then move to the water supply position.

In this embodiment, even when the full ice is detected, the reason for the ice separation is as follows.

If, after completion of the ice making, the full ice is detected to stand by in a state in which ice exists in the ice making cell 320a, the ice in the ice making cell 320a may be melted due to an abnormal situation such as power outage, cut-off of the power supply, and the like.

In this state, when the abnormal situation is released, the water melted in the ice making cell 320a may be changed to ice again.

However, since the full ice has already been detected, the transparent ice heater does not operate and stands by at the water supply position. Thus, the ice generated in the ice making cell 320a is not transparent.

When opaque ice is separated because the full ice is not detected later, the user uses the opaque ice, which may cause emotional dissatisfaction of the user.

If, after completion of the ice making, the full ice is detected to stand by in a state in which ice exists in the ice making cell 320a, the ice in the ice making cell 320a may be melted due to an abnormal situation such as opening of the door for a long time, proceeding of a defrosting operation, and the like.

As described above, in the state in which the second tray stands by at the water supply position, the full ice is detected again after a set time. Here, if melted water exists in the ice making cell 320a, the water may drop into the ice bin <NUM> in the movement process of the second tray <NUM>. In this case, a problem occurs in that ice stored in the ice bin <NUM> sticks to each other by the dropping water.

However, as in this embodiment, when ice does not exist in the ice making cell in the standby process after the full ice detection, the above problem may be fundamentally controlled.

On the other hand, in the case of this embodiment, when the second tray <NUM> stands by at the water supply position when detecting the full ice, the second tray <NUM> may be prevented from sticking to the first tray <NUM>, and thus, when the full ice is detected later, the second tray <NUM> may move smoothly.

In another aspect, the present invention may include an embodiment, in which the controller <NUM> controls the transparent ice heater <NUM> to be turned again on after the abnormal situation is terminated so as to reduce deterioration in transparency of the ice in the process, in which an external thermal load is introduced into the ice making cell 320a in the abnormal situation, and thus, the ice within the ice making cell 320a is repetitively melted and re-frozen.

When all of the ices are melted due to the abnormal situation, after the abnormal situation is terminated, one or more of the cooling power of the cold air supply part <NUM> and the heating amount of the heater may be controlled to vary in the same manner in which the ice making process performed by the controller <NUM> before the ice is melted.

However, when only a portion of the ice is melted due to the abnormal situation, after the abnormal situation is terminated, the cooling power of the cold air supply part <NUM> may be reduced, or the heating amount of the heater is reduced when compared to the ice making process performed by the controller <NUM> before the ice is melted.

Here, it is not easy to control the cooling power of the cold air supply part <NUM> and the heating amount of the heater so that the ice transparency before being re-frozen and the ice transparency after being re-frozen are matched.

This is done because, when ice is melted, the ice is gradually melted from the outside to the inside thereof, whereas since the transparent ice heater <NUM> locally heats one side of the ice making cell 320a so that bubbles dissolved in the water inside the ice making cell 320a move from the portion at which the ice is generated toward the water that is in the liquid state to induce the generation of the transparent ice, it is difficult to maintain the ice making rate when the ice is re-frozen at the same rate as before being re-frozen.

Particularly, among the embodiments of the present invention, in case of an embodiment, in which the controller <NUM> controls one or more of the cooling power of the cold air supply part <NUM> and the heating amount of the heater to vary according to a mass per unit height of water in the ice making cell 320a, it may be difficult to supply the cooling power and the heating amount when the ice is re-frozen in the same or similar manner as being re-frozen, and thus, the re-frozen ice may have transparency different from that of the existing frozen ice.

When the full ice of the ice bin <NUM> is detected by the full ice detection part <NUM>, it may be designed so that a state, in which <NUM>% of ice is not filled in the ice bin <NUM> is detected as the full ice so as to allow the controller <NUM> to control the driver so that the second tray <NUM> moves to the ice separation position after the ice making is completed.

This is because it is necessary to perform an additional one-time ice separation process after the full ice is detected. Thus, the present invention is characterized in that the controller <NUM> detects that the ice bin <NUM> is full when the total volume of separated ice inside the ice bin <NUM> reaches a reference value set within a range less than the total volume of the ice bin <NUM>.

When the total volume of separated ice (i.e., volume of ice making cell x number of times of separation of ice) reaches a full ice reference value (a range between the minimum and maximum values of the full ice reference value) set within a specific range, the controller <NUM> detects the state as the full ice. The full ice reference value may be set as follows.

<NUM>% of total volume of ice bin ≤ the full ice reference value ≤ total volume of ice bin - volume of ice making cell.

In an example in which an optical sensor is used for detecting the full ice, an optical sensor may be disposed so that a height of a parallel line connecting a light emitting part and a light receiving part of the optical sensor is greater than a height corresponding to <NUM>% of the total volume of the ice bin and is equal or less than the maximum value of the full ice reference value.

In an example of using a rotation-type lever for detecting the full ice, the lever may be disposed so that a height of the lowest position of the lever is greater than a height corresponding to <NUM>% of the total volume of the ice bin and is equal or less than the maximum value of the full ice reference value, based on a rotation path along which the rotation-type lever moves.

In an example of using a linearly movable lever for detecting the full ice, the lever may be disposed so that a height of the lowest position of the lever is greater than a height corresponding to <NUM>% of the total volume of the ice bin and is equal to less than the maximum value of the full ice reference value, based on a linear path along which the linear lever moves.

Since the rotation arm <NUM> is connected to the cam <NUM>, the rotation angle of the cam <NUM> in the process of moving from the ice making position to the ice separation position or the process of moving from the ice separation position to the ice making position may be the same as that of the second tray assembly.

However, in a state in which the rotation arm <NUM> is coupled to the second tray supporter <NUM>, the rotation arm <NUM> and the second tray supporter <NUM> may rotate relative to each other within a predetermined angle range. For example, the through-hole <NUM> of the second tray supporter <NUM> may include a circular first portion and a pair of second portions extending symmetrically from the first portion.

The rotation arm <NUM> may include a protrusion disposed in the through-hole <NUM> in a state of being coupled to the shaft <NUM>. The protrusion may include a cylindrical first protrusion. The first protrusion may be coupled to the first portion of the through-hole <NUM>. The shaft <NUM> may be coupled to the first protrusion.

The coupling part may include a plurality or pair of second protrusions protruding in a radial direction of the first protrusion. The second protrusion may be disposed in the second portion of the through-hole.

A length of the second portion in a circumferential direction based on a rotation center of the shaft <NUM> may be greater than that of the second protrusion so that the second tray supporter <NUM> and the rotation arm <NUM> relatively rotate with respect to each other in the predetermined angle range.

Thus, in the state in which the second protrusion <NUM> is disposed at the second portion, the second tray supporter <NUM> and the rotation arm <NUM> may relatively rotate with respect to each other in a range of a difference between the length of the second protrusion <NUM> in the circumferential direction and the length of the second portion in the circumferential direction.

Due to this structure, in the state in which the second tray assembly moves to the ice making position, the cam <NUM> may additionally rotate while the second tray assembly is stopped.

Referring to <FIG>, the ice making position may be a position at which at least a portion of the ice making cell formed by the second tray <NUM> reaches a reference line passing through the rotation center (rotation center of the driver) of the shaft <NUM>. Referring to <FIG>, the water supply position may be a position before at least a portion of the ice making cell formed by the second tray <NUM> reaches the reference line passing through the rotation center C4 of the shaft <NUM>.

It is assumed that the rotation angle of the cam <NUM> is <NUM> at the ice making position. The cam <NUM> may additionally rotate in the reverse direction due to the difference in length between the second protrusion of the rotation arm <NUM> and the second portion of the extension hole <NUM>. That is, at the ice making position of the second tray assembly, the cam <NUM> may additionally rotate in the reverse direction.

At the ice making position, the rotation angle of the cam <NUM> when the cam <NUM> rotates in the reverse direction may be referred to as a negative (-) rotation angle.

At the ice making position, the rotation angle of the cam <NUM> when the cam <NUM> rotates in the forward direction toward the water supply position or the ice separation position may be referred to as a positive (+) rotation angle. Hereinafter, in the case of the positive (+) rotation angle, the positive (+) value will be omitted.

At the ice making position, the cam <NUM> may rotate to the water supply position at a first rotation angle. The first rotation angle may be greater than <NUM> degrees and less than <NUM> degrees. Preferably, the first rotation angle may be greater than <NUM> degrees and less than <NUM> degrees.

Since the water dropping into the second tray <NUM> is evenly spread into the plurality of ice making cell 320a by the setting of the water supply position according to the present invention, the overflowing of the water dropping into the second tray <NUM> may be prevented.

At the ice making position, the cam <NUM> may rotate to the ice making position at a second rotation angle. A rotation angle of the second may be greater than <NUM> degrees and less than <NUM> degrees. Preferably, the second rotation angle may be greater than <NUM> degrees and less than <NUM> degrees. More preferably, the second rotation angle may be greater than <NUM> degrees and less than <NUM> degrees.

When the second rotation angle is greater than <NUM> degrees, ice may be easily separated from the second tray <NUM> while the second tray <NUM> is pressed by the second pusher <NUM>. As a result, the separated ice may smoothly drop down without being caught on the end of the second tray <NUM>.

At the ice separation position, the cam <NUM> may additionally rotate at a third angle. The cam <NUM> may additionally rotate in the forward direction at the third rotation angle in the state in which the second tray assembly moves to the ice separation position by an assembly tolerance of the cam <NUM> and the rotation arm <NUM>, a difference in rotation angle of the pair of rotation arms due to the cam <NUM> being coupled to one of the pair of rotation arms <NUM>, and the like. When the cam <NUM> further rotates in the forward direction, pressing force applied by the second pusher <NUM> to press the second tray <NUM> may increase.

At the ice separation position, the cam <NUM> may rotate in the reverse direction, and after the second tray assembly moves to the water supply position, the cam <NUM> may further rotate in the reverse direction. The reverse direction may be a direction opposite to the direction of gravity. In consideration of the inertia of the tray assembly and the motor, if the cam further rotates in the direction opposite to the direction of gravity, it is advantageous in controlling the water supply position.

Claim 1:
A refrigerator comprising:
a storage chamber configured to store food;
a cold air supply part (<NUM>) configured to supply cold air to the storage chamber;
a first tray (<NUM>) configured to define one portion of an ice making cell (320a) that is a space in which water is phase-changed into ice by the cold air;
a second tray (<NUM>) configured to define the other portion of the ice making cell (320a), the second tray (<NUM>) being connected to a driver (<NUM>) to contact the first tray (<NUM>) in an ice making process and to be spaced apart from the first tray (<NUM>) in an ice separation process;
a heater (<NUM>) disposed adjacent to at least one of the first tray (<NUM>) or the second tray (<NUM>);
an ice bin (<NUM>) configured to store ice dropped from the ice making cell (320a);
a full ice detection part (<NUM>) configured to detect full ice of the ice bin (<NUM>); and
a controller (<NUM>) configured to control the heater (<NUM>) and the driver (<NUM>),
characterized in that the controller (<NUM>) is configured to control the driver (<NUM>) so that:
the second tray (<NUM>) moves to an ice making position from a water supply position after water supply to the ice making cell (320a) is completed to allow the cold air supply part (<NUM>) to supply the cold air to the ice making cell (320a);
the second tray (<NUM>) moves to an ice separation position in a forward direction so as to take out ice in the ice making cell (320a) after the ice is completely generated in the ice making cell (320a) and then moves back in a reverse direction;
the second tray (<NUM>) moves to a water supply position to start the water supply after the ice separation is completed; and
when the full ice of the ice bin (<NUM>) is detected by the full ice detection part (<NUM>), the second tray (<NUM>) is configured to move to the ice separation position only after the ice making is completed.