Patent Description:
In general, refrigerators are home appliances for storing foods at a low temperature in a storage chamber 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 may separate the made ice from the ice tray in a heating manner or twisting manner.

Water is automatically supplied through the ice maker, and the ice automatically separated is pumped up.

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> that is a prior art document.

The ice maker disclosed in the prior art document 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 a state in which both ends thereof are inserted into the link guide part and elevated together with the upper ejecting pin assembly.

In the case of the prior art document, the ice maker further includes an ice separation heater that contacts the upper tray for ice separation, but it is difficult to determine an appropriate ice separation time due to different ice separation time points between the plurality of cells.

In addition, in the case of the prior art document, there are problems that, as the ice separation time points are different between the plurality of cells, excessive melting is made by the heat of the ice separation heater in some cells, the surface of the ice becomes opaque or non-smooth, and the melting water descends into the ice bin and thus a mat of the ice cubes is generated inside the ice bin.

<CIT> presents an ice maker including: an upper tray including a plurality of upper cells that each have a hemispherical shape and an ice making tube disposed at outer circumferential surfaces of the upper cells and configured to cool each of the upper cells; a lower tray that includes a plurality of lower cells that each have a hemispherical shape, the lower tray being rotatably connected to the upper tray; and a rotation shaft connected to a rear end of the lower tray and a rear end of the upper tray, and configured to rotate the lower tray with respect to the upper tray.

Embodiments provide a refrigerator in which ice separation is smoothly performed by determining an appropriate ice separation time point in an ice maker including a plurality of cells, and a method for controlling the same.

Embodiments provide a refrigerator which is capable of generating ice having a spherical smooth surface and uniform transparency as a whole, and a method for controlling the same.

Embodiments provide a refrigerator which can prevent the phenomenon that the melting water is settled inside the ice bin so that a mat of ice cubes is generated inside the ice bin or the ice inside the ice bin melts by the melting water, and a method for controlling the same.

A method for controlling a refrigerator according to an aspect includes turning on the heater when ice making is completed and when a movement condition of the second tray is satisfied: moving the second tray to a standby position in the forward direction and then turning off the heater when a turn-off condition of the heater is satisfied, only after the second tray moves to the standby position, or turning off the heater and then moving the second tray to a standby position in the forward direction; determining whether the heater is turned off and a predetermined time has elapsed; and moving the second tray to the ice separation position in the forward direction when it is determined that the predetermined time has elapsed.

As an example, when the movement condition of the second tray is satisfied, and when the second tray is moved to the standby position, the heater may be turned on again.

Whether the movement condition of the second tray is satisfied may be determined based on at least one of a turn-on time of the heater and a temperature sensed by a temperature sensor for sensing the temperature of the ice making cell.

When the turn-on time of the heater elapses a first reference time and the temperature sensed by the temperature sensor reaches a first turn-off reference temperature, it may be determined that the movement condition of the second tray is satisfied.

When the second reference time shorter than the first reference time elapses in a state in which the heater is turned on again, it may be determined that the turn-off condition of the heater is satisfied.

The predetermined time may be longer than the second reference time.

In addition, as an example in which the heater is turned off and a predetermined time lapses, the second tray may wait at the standby position until the predetermined time elapses after the heater is turned off.

As another example, the second tray may move to a specific position between the standby position and the ice separation position and may wait until the predetermined time elapses from the moved position after the heater is turned off.

The first tray may be formed of a metal material or a silicon material.

The refrigerator may further include a pusher having a length formed in a vertical direction of the ice making cell larger than a length formed in a horizontal direction of the ice making cell so that ice is easily separated from the first tray.

Meanwhile, an additional heater positioned at one side of the first tray or the second tray may be turned on in at least partial sections while the cold air supply part supplies cold air so that the bubbles dissolved in the water inside the ice making cell move from the ice-generating portion to the liquid water to generate transparent ice.

When the additional heater may be turned off and the temperature sensed by a temperature sensor for sensing the temperature of the ice making cell is equal to or less than a reference temperature, it is determined that ice making is completed and thus the heater is turned on.

According to the invention, a refrigerator comprising the technical features of independent claim <NUM> is disclosed.

Also, a controller may control the heater to be turned off when a turn-off condition of the heater is satisfied after the heater is secondly turned on and the second tray to wait at the standby position until a predetermined time elapse.

According to the proposed invention, it is possible to secure the ice separation reliability by determining the optimal ice separation time point in an ice maker having different ice separation time points between respective cells, by including a plurality of cells.

In addition, after the tray is firstly heated by the ice separation heater, the lower tray is separated from the ice separation heater, thereby preventing excessive melting due to the difference in ice separation time point between ice making cells.

In addition, after separation of the lower tray from the ice separation heater, in the case of an ice making cell that has not yet reached the ice separation time point, it is possible to secure the ice separation reliability by making the ice making cell reach the ice separation time point through additional heating.

In addition, after additional heating, the water melting by the ice separation heater waits without ice separation for a predetermined time to cool, and thus the phenomenon that the melting water is settled in the ice bin, and a mat of the ice cubes is generated inside the ice bin or the ice inside the ice bin melts by the melting water can be prevented.

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

Referring to <FIG>, a refrigerator according to an embodiment includes 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 chambers 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> falls 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 an ice maker according to an embodiment. <FIG> is a perspective view illustrating a state in which a bracket is removed from the ice maker of <FIG>. <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> for illustrating a second temperature sensor installed in the ice maker according to an embodiment of the present invention.

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

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>. A water supply part <NUM> may be installed above the inner surface of the bracket <NUM>. The water supply part <NUM> is provided with openings at the upper and lower sides, respectively, so that water supplied to the upper side of the water supply part <NUM> may be guided to the lower side of the water supply part <NUM>. The upper opening of the water supply part <NUM> is larger than the lower opening, and thus a discharge range of water guided downward through the water supply part <NUM> may be limited. A water supply pipe through which water is supplied may be installed above 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> includes an ice making cell <NUM> in which water is phase-changed into ice by the cold air.

The ice maker <NUM> includes a first tray <NUM> forming at least a portion of a wall for providing the ice making cell 320a, and a second tray <NUM> forming at least another portion of the wall for 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> is disposed to be relatively movable with respect to the first tray <NUM>. The second tray <NUM> may linearly move 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> moves 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> contact each other, the complete ice making cell 320a may be defined. On the other hand, the second tray <NUM> moves 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 formed. 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>. Hereinafter, in <FIG>, three ice making cells 320a are provided as an example.

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. The ice making cell 320a may have a rectangular parallelepiped shape or a polygonal shape. In this case, the first cell 320b may have a hemispherical shape or a shape similar to that of a hemisphere. In addition, the second cell 320c may be formed in a hemispherical shape or a shape similar to that of a hemisphere.

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> and the bracket <NUM> may be integrally provided or coupled to each other with each other after being manufactured in separate configurations.

The ice maker <NUM> may further include a first heater case <NUM>. An ice separation heater <NUM> may be installed in the first 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>. The ice separation heater <NUM> may be, for example, a wire type heater. For example, the ice separation heater <NUM> may be installed to contact the first tray <NUM> or may be disposed at a position spaced a predetermined distance from the first tray <NUM>. In some case, 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> positioned below the first tray <NUM>. The first tray cover <NUM> has an opening formed to correspond to the shape of the ice making cell 320a of the first tray <NUM> and thus may be coupled to the lower surface of the first tray <NUM>.

The first tray case <NUM> may be provided with a guide slot <NUM> inclined at an upper side and vertically extending at a lower side. 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. For example, 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 a 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 includes a second tray case <NUM> coupled to the second tray <NUM>. The second tray case <NUM> may support the second tray <NUM> at a lower side of 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 cover <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 at least a portion of 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 sections 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 a 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 a resin including plastic so that the ice attached to the trays <NUM> and <NUM> is separated well during the ice separation process.

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

The transparent ice heater <NUM> may be disposed at a position adjacent to the second tray <NUM>. The transparent ice heater <NUM> may be a wire type heater, as an example. As an example, the transparent ice heater <NUM> may be installed to contact the second tray <NUM> or may be disposed at a position spaced apart from the second tray <NUM> by a predetermined distance. As another example, the second heater case <NUM> may not be separately provided, and the transparent ice heater <NUM> may be installed in 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> further includes a driver <NUM> that provides driving force. The second tray <NUM> relatively moves 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>. At least a portion of the through-hole <NUM> may be disposed at a position higher than a horizontal line passing through a center of the ice making cell 320a. 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.

The driver <NUM> may include a motor and a plurality of gears.

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 U-shaped 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>. 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 driver <NUM> may further include a cam that rotates by the rotational power of the motor. The ice maker <NUM> may further include a sensor that senses the rotation of the cam.

For example, the cam is provided with a magnet, and the sensor may be a hall sensor detecting magnetism of the magnet during the rotation of the cam. The sensor may output first and second signals that are different outputs according to whether the sensor senses a magnet. One of the first signal and the second signal may be a high signal, and the other may be a low signal.

The controller <NUM> to be described later may determine a position of the second tray <NUM> based on the type and pattern of the signal outputted from the sensor. That is, since the second tray <NUM> and the cam rotate by the motor, the position of the second tray <NUM> may be indirectly determined based on a detection signal of the magnet provided in the cam.

For example, a water supply position, an ice making position, and an ice separation position, which will be described later, may be distinguished and determined based on the signals outputted from the sensor.

The ice maker <NUM> may further include a second pusher <NUM>. The second pusher <NUM> may be installed, for example, 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 out 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 320a and then press the contacting second tray <NUM>.

Therefore, the second tray case <NUM> may include 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 case <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 flexible or soft material which is deformable. Although not limited, the second tray <NUM> may be made of, for example, 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.

On the other hand, 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, for example, 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) to sense 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 apart from the first tray <NUM> by a predetermined distance. Alternatively, the second temperature sensor <NUM> may be installed on the first tray <NUM> to contact the first tray <NUM>. Of course, in a case in which the second temperature sensor <NUM> is disposed to pass through the first tray <NUM>, the second temperature sensor <NUM> may directly sense the temperature of the water or the temperature of ice of the ice making cell 320a.

Meanwhile, a portion of the ice separation heater <NUM> may be positioned higher than the second temperature sensor <NUM> and may be spaced apart from the second temperature sensor <NUM>. An electric wire <NUM> connected to the second temperature sensor <NUM> may be guided above the first tray case <NUM>.

Referring to <FIG>, the ice maker <NUM> according to this embodiment may be designed so that the positions of the second tray <NUM> are different from each other at a water supply position and an 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 cells 320a and a peripheral wall <NUM> extending along an outer edge of the second cell wall <NUM>.

The second cell wall <NUM> may include an upper surface 381a. In this specification, the upper surface 381a of the second cell wall <NUM> may be referred to as the upper surface 381a of the second tray <NUM>. The upper surface 381a of the second cell wall <NUM> may be positioned lower than the upper end portion of the peripheral wall <NUM>.

The first tray <NUM> may include a first cell wall 321a defining a first cell 320b of the ice making cells 320a. The first cell wall 321a may include a straight portion 321b and a curved portion 321c. The curved portion 321c may be formed in an arc shape having a center of the shaft <NUM> as a radius of curvature. Accordingly, the peripheral 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 lower surface 321d. In the present specification, the lower surface 321b of the first cell wall 321a may be referred to be the lower surface 321b of the first tray <NUM>. The lower surface 321d of the first cell wall 321a may contact the upper surface 381a of the second cell wall 381a.

For example, in the water supply position as illustrated in <FIG>, at least a portion of the upper surface 381a of the second cell wall <NUM> and the lower surface 321d of the first cell wall 321a may be spaced apart from each other. In <FIG>, as an example, it is illustrated that all the upper surface 381a of the second cell wall <NUM> and the lower surface 321d of the first cell wall 321a are spaced apart from each other. Accordingly, the upper surface 381a of the second cell wall <NUM> may be inclined to form a predetermined angle with the lower surface 321d of the first cell wall 321a.

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

In the state illustrated in <FIG>, the peripheral wall <NUM> may surround the first cell wall 321a. In addition, the upper end portion of the circumferential wall <NUM> may be positioned higher than the lower surface 321d of the first cell wall 321a.

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

The angle between the upper surface 381a of the second tray <NUM> and the lower surface 321d of the first tray <NUM> at the ice making position is smaller than the angle between the upper surface 382a of the second tray <NUM> and the lower surface 321d of the first tray <NUM> at the water supply position. In the ice making position, the upper surface 381a of the second cell wall <NUM> may contact all the lower surface 321d of the first cell wall 321a. In the ice making position, an upper surface 381a of the second cell wall <NUM> and a lower surface 321d of the first cell wall 321a may be disposed to be substantially horizontal.

In this embodiment, the reason why the water supply position and the ice making position of the second tray <NUM> are different is that in a case in which the ice maker <NUM> includes a plurality of ice making cells 320a, water is to be uniformly distributed to the plurality of ice making cells 320a without forming a water passage for communication between respective ice making cells 320a in the first tray <NUM> and/or the second tray <NUM>.

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

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

In this case, there is a possibility that the ices will stick to each other even after the ice separation is completed, and even if the ice is separated from each other, some of the plurality of the ices contains ice generated in the water passage portion, so there is a problem that the shape of the ice is different from the shape of the ice in the ice making cell.

However, as in this embodiment, in a state in which the second tray <NUM> is spaced apart from the first tray <NUM> at the water supply position, the water dropped 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. In a case in which 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 among the plurality of communication holes 321e. In this case, water supplied through the one communication hole 321e drops into the second tray <NUM> after passing through the first tray <NUM>.

During the water supply process, water may drop into any one second cell 320c of the plurality of second cells 320c of the second tray <NUM>. Water supplied to one second cell 320c overflows from one second cell 320c.

In this embodiment, since the upper surface 381a of the second tray <NUM> is spaced apart from the lower surface 321d of the first tray <NUM>, the water overflowing from the one second cell 320c moves to another adjacent second cell 320c along the upper surface 381a of the second tray <NUM>. Accordingly, water may be fully filled in the plurality of second cells 320c of the second tray <NUM>.

In addition, in a state in which the water supply is completed, a portion of the water supplied can be fully filled in the second cell 320c, and another portion of the water supplied can be filled in the space between the first tray <NUM> and the second tray <NUM>.

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

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

Meanwhile, when a water passage is formed in the first tray <NUM> and/or the second tray <NUM>, ice generated in the ice making cell 320a is also generated in the water passage portion.

In this case, in order to generate transparent ice, when the controller of the refrigerator controls so that at least one of the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater <NUM> are varied according to the mass per unit height of water in the ice making cell 320a, at least one of the cooling power of the cold air supply part <NUM> and the heating amount of the transparent ice heater <NUM> in the portion where the water passage is formed is controlled to be rapidly varied several times or more.

This is because the mass per unit height of water rapidly increases several times or more in the portion where the water passage is formed. In this case, reliability problems of parts may occur, and expensive parts in which width between the maximum output and minimum output is large can be used, which may be disadvantageous in terms of power consumption and cost of the parts. As a result, the present invention may require a technique related to the above-described ice making position to also generate transparent ice.

<FIG> is a block diagram illustrating a control of a refrigerator according to an embodiment.

Referring to <FIG>, the refrigerator according to this embodiment may include a cold 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. The 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 the amount of refrigerant flowing through the refrigerant cycle. The 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>.

The refrigerator may further include a water supply valve <NUM> controlling the amount of water supplied through the water supply part <NUM>. The refrigerator may further include a door opening/closing detector <NUM> for detecting opening/closing of a door of a storage chamber (for example, the freezing compartment <NUM>) in which the ice maker <NUM> is installed.

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 addition, when the door opening/closing detector <NUM> detects the opening/closing of the door (a state in which the door is open and closed), the controller <NUM> may determine whether the cooling power of the cold air supply part <NUM> is varied based on the temperature detected by the first temperature sensor <NUM>.

In addition, when the door opening/closing detector <NUM> detects the opening/closing of the door, the controller <NUM> may determine whether the output of the transparent ice heater <NUM> is varied based on the temperature detected by the second temperature sensor <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 an internal temperature sensor) that senses a temperature of the freezing compartment <NUM>. The controller <NUM> may control the cold air supply part <NUM> based on the temperature sensed by the first temperature sensor <NUM>. The controller <NUM> may determine whether ice making is completed based on the temperature sensed by the second temperature sensor <NUM>.

<FIG> is a flowchart for explaining a process of making ice in the ice maker according to an embodiment. <FIG> is a flowchart illustrating a process in which ice is separated in an ice maker according to an embodiment of the present invention.

<FIG> is a view illustrating a state in which water supply is completed at a water supply position, <FIG> is a view illustrating a state in which ice is generated at the ice making position,.

<FIG> is a view illustrating a state in which a second tray has been moved to a standby position during an ice separation process, <FIG> is a view illustrating a state in which the second tray and the first tray are separated from each other during an ice separation process, and <FIG> is a view illustrating a state in which a second tray is moved to an ice separation position during an ice separation process.

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 of <FIG> to the ice separation position of <FIG> may be referred to as forward movement (or forward rotation). On the other hand, the direction from the ice separation position of <FIG> to the water supply position of <FIG> may be referred to as reverse movement (or reverse rotation).

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

The water supply starts when the second tray <NUM> moves to the water supply position (S2). For the water supply, the controller <NUM> turns on the water supply valve <NUM>, and when it is determined that a predetermined amount of water 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 a predetermined amount of water 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> moves in the reverse direction, the second contact surface 382c of the second tray <NUM> comes close to the upper surface 381a of the first tray <NUM>. Then, water between the upper surface 381a of the second tray <NUM> and the lower surface 321e of the first tray <NUM> is divided into each of the plurality of second cells 320c and then is distributed. When the upper surface 381a of the second tray <NUM> and the lower surface 321e of the first tray <NUM> contact each other, water is filled in the first cell 321a.

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). 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 cool 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 (S5).

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. 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.

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.

In this embodiment, the controller <NUM> determines that the turn-on condition of the transparent ice heater <NUM> is satisfied when a temperature sensed 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 (side of the communication hole) 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 is present in the ice making cell 320a, after the ice starts to be made in the ice making cell 320a, the temperature sensed 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 sensed 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 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.

When 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 control part <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 a sum 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-off time and a sum 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>.

If 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.

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.

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 gradually increase.

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 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 sensed by the second temperature sensor <NUM> (S6). When it is determined that the ice making is completed, the controller <NUM> may turn off the transparent ice heater <NUM> (S7).

For example, when the temperature sensed 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 sensed by the second temperature sensor <NUM> reaches a second reference temperature lower than the first reference temperature.

When the ice making is completed, the controller <NUM> operates the ice separation heater <NUM> for ice separation (S8). When the ice separation heater <NUM> is turned on, heat from the heater is transferred to the first tray <NUM> so that ice may be separated from the surface (inner surface) of the first tray <NUM>.

In addition, the heat of the ice separation heater <NUM> is transferred from the first tray <NUM> to the contact surface of the second tray <NUM>, so that the lower surface 321d of the first tray <NUM> and the upper surface 381a of the second tray <NUM> are in a state of being capable of being separated.

However, when the heat transfer amount between the cold air in the freezing compartment <NUM> and the water in the ice making cell 320a is varied, if the heating amount of the ice separation heater <NUM> is not adjusted to reflect this, there is a problem that ice separation is not smooth since the ice excessively melt or ice does not melt enough.

In this embodiment, a case in which the heat transfer amount of cold air and water increases may be, for example, a case in which the cooling power of the cold air supply part <NUM> increases, or a case in which air having a temperature lower than the temperature of the cold air in the freezing compartment <NUM> is supplied to the freezing compartment <NUM>.

On the other hand, a case in which the heat transfer amount of cold air and water is reduced may be, for example, a case in which the cooling power of the cold air supply part <NUM> is reduced, a case in which the door is opened and air having a temperature higher than the temperature of the cold air in the freezing compartment <NUM> is supplied to the freezing compartment <NUM>, a case in which food having a temperature higher than the temperature of cold air in the freezing compartment <NUM> is put into the freezing compartment <NUM>, or a state in which a defrost heater (not illustrated) for defrosting the evaporator is turned on.

For example, in a case in which the target temperature of the freezing compartment <NUM> decreases, the operating mode of the freezing compartment <NUM> is changed from the normal mode to the rapid cooling mode, the output of at least one of the compressor and the fan increases, or the opening degree of the refrigerant valve increases, the cooling power of the cold air supply part <NUM> may increases.

On the other hand, in a case in which the target temperature of the freezing compartment <NUM> increases, the operating mode of the freezing compartment <NUM> is changed from the rapid cooling mode to the normal mode, the output of at least one of the compressor and the fan is reduced, or the opening degree of the refrigerant valve is reduced, the cooling power of the cold air supply part <NUM> may be reduced.

In a case in which the heat transfer amount of the cold air and water increases, the temperature of the cold air around the ice maker <NUM> decreases, so that the rate of ice generation increases.

On the other hand, when the heat transfer amount of the cold air and water is reduced, the temperature of the cold air around the ice maker <NUM> increases, so that the rate of ice generation is slowed, and the ice making time is lengthened.

Accordingly, in this embodiment, in a case in which the heat transfer amount of cold air and water increases, the heating amount of the ice separation heater <NUM> may be controlled to increase. On the other hand, in a case in which the heat transfer amount of the cold air and water is reduced, the heating amount of the ice separation heater <NUM> may be controlled to be reduced.

As another example, it goes without saying that the ice separation heater <NUM> may transfer heat to the first tray <NUM> with constant output.

In this case, the controller <NUM> may determine the output of the ice separation heater <NUM> in consideration of an initial condition in order to solve a problem in which ice separation is not smooth due to external factors.

The initial condition may include a cooling power of the cold air supply part <NUM>, a target temperature of the storage chamber, a door opening time, and a turn-on time of the defrost heater.

In detail, if the cooling power of the cold air supply part <NUM> is higher when the cooling power of the cold air supply part <NUM> is the second cooling power than when the cooling power thereof is the first cooling power during the ice making process, the controller can control the heating amount of the ice separation heater <NUM> to be larger when the cooling power of the cold air supply part <NUM> is the second cooling power than when the cooling power thereof is the first cooling power.

The high cooling power of the cold air supply part <NUM> means that the heat transfer amount of cold air and water increases, so as to prevent the case where the ice is not separated due to insufficient heating amount of the ice separation heater <NUM> if the cooling power of the cold air supply part <NUM> is high, the heating amount of the ice separation heater <NUM> may be controlled to be larger.

In addition, if the target temperature of the storage chamber set by the user is higher in the second temperature than in the first temperature, the controller <NUM> can control so that the heating amount of the ice separation heater <NUM>, when the target temperature is the second temperature is smaller.

This is to prevent the case in which the target temperature of the storage chamber is set higher so that the ice excessively melts by the ice separation heater <NUM>.

In addition, according to a similar principle, if the door opening time in the ice making process or the turn-on time of the defrost heater operating for defrosting is longer in the second time than in the first time, the controller <NUM> can control so that the heating amount of the ice separation heater <NUM> is smaller when the door opening time in the ice making process or the turn-on time of the defrost heater operating for defrosting is the second time.

After the ice separation heater <NUM> is turned on when the moving condition of the second tray <NUM> is satisfied, the controller <NUM> can rotate the second tray <NUM> in the forward direction so that the second tray <NUM> is moved to a standby position (or an additional heating position) in the forward direction (S9).

The moving condition of the second tray <NUM> may be determined based on at least one of the turn-on times of the ice separation heater <NUM> and a temperature sensed by the second temperature sensor <NUM>.

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

As an example, as illustrated in <FIG>, the standby position may be a state in which the second tray <NUM> is moved further in the forward direction than the water supply position, and the second tray <NUM> is moved further in the reverse direction than the ice separation position. That is, the additional heating position may be between the water supply position and the ice separation position.

In detail, the angle between the lower surface 321d of the first tray <NUM> and the upper surface 381a of the second tray <NUM> at the additional heating position may be referred to as a first angle, and the first angle may be <NUM> degrees to <NUM> degrees.

In this embodiment, before the second tray <NUM> rotates in the forward direction, ice may be separated from the surface of the first tray <NUM> by the heat of the turned-on ice separation heater <NUM>.

In this case, the ice may move together with the second tray <NUM> in a state of being supported by the second tray <NUM>.

As another example, even if the heat of the ice separation heater <NUM> is applied to the first tray <NUM>, there may be a case where ice is not separated from the surface of the first tray <NUM>.

That is, when the second tray <NUM> is moved to the additional heating position, ice may be in a state of being settled on the second tray <NUM> in a cell separated from the first tray <NUM> among the plurality of ice making cells 320a and in the remaining cells, ice may be in a state of being attached to the first tray <NUM>.

After the second tray <NUM> is rotated in the forward direction to the standby position, it is determined whether the turn-off reference of the ice separation heater <NUM> is satisfied (S10).

The turn-off reference of the ice separation heater <NUM> may be determined based on at least one of the turn-on times of the ice separation heater <NUM> and a temperature sensed by the second temperature sensor <NUM>.

When the turn-off reference of the ice separation heater <NUM> is satisfied, the controller <NUM> turns off the ice separation heater <NUM> (S11).

After the ice separation heater <NUM> is turned on, until the ice separation heater <NUM> is turned off, the ice separation heater <NUM> may maintain a turn-on state when the second tray <NUM> moves to the standby position.

Another example after the ice separation heater <NUM> is turned on, until the ice separation heater <NUM> is turned off and then the second tray <NUM> moves to the ice separation position will be described with reference to <FIG>.

After the ice making heater <NUM> first transfers heat from the ice making position to the ice making cell 320a and is turned off, the second tray <NUM> is moved to the standby position, and the ice separation heater <NUM> may be turned on at the standby position again.

That is, when the moving condition of the second tray <NUM> is satisfied, the controller <NUM> may turn off the ice separation heater <NUM>, and when the second tray <NUM> is moved to the standby position, the controller <NUM> may turn on the ice separation heater <NUM> again.

The moving condition of the second tray <NUM> for turning off the ice separation heater <NUM> may be a case in which the temperature sensed by the second temperature sensor <NUM> reaches the turn-off reference temperature (or first turn-off reference temperature) or more of the ice separation heater <NUM> or (S81), or a case of being operated during the turn-off reference time (S82). The turn-off reference time may be referred to as a first reference time.

In addition, in a case in which the temperature sensed by the second temperature sensor <NUM> reaches the first turn-off reference temperature during the turn-off reference time, the ice separation heater <NUM> may be turned off.

As an example, when the temperature sensed by the second temperature sensor <NUM> reaches the first turn-off reference temperature during a sufficient turn-off reference time to allow all ice to be separated in the plurality of ice making cells 320a, it may be determined that the moving condition of the tray <NUM> is satisfied.

However, in this case, some of the plurality of ice making cells 320a may excessively melt, and thus melting water may drop into the ice bin <NUM>.

Accordingly, as another example, a turn-off reference time or a first turn-off reference temperature at which only some of the plurality of ice making cells 320a are separated may be set.

That is, the first turn-off reference temperature may be a temperature at which it is determined that ice in some ice making cells 320a among the plurality of ice making cells 320a can be separated, and the turn-off reference time may be a time at which it is determined that ice in some ice making cells 320a among the plurality of ice making cells 320a can be separated.

Although not limited, the first turn-off reference temperature may be set as the above-zero temperature. Alternatively, the first turn-off reference temperature may be set to a temperature higher than the first reference temperature.

When the movement condition of the second tray <NUM> is satisfied, the controller <NUM> turns off the ice separation heater <NUM> (S83).

After the ice separation heater <NUM> is turned off, the second tray <NUM> is moved to the standby position (S9).

The controller <NUM> may turn on the ice separation heater <NUM> again for additional heating for separating ice attached to the first tray <NUM> (S84).

In detail, even after the second tray <NUM> is moved to the additional heating position, since some of the ice making cells 320a are attached to the first tray <NUM> and remain in a state of not melting, the controller <NUM> may operate the ice separation heater <NUM>.

By additionally operating the ice separation heater <NUM>, the load applied to the first pusher <NUM> may be reduced, thereby preventing the first pusher <NUM> from being damaged.

After the ice separation heater <NUM> is operated, when the second reference time elapses, the ice separation heater <NUM> may be turned off (S85, S11).

The second reference time may be a time sufficient to melt ice attached to the first tray <NUM> and not settled in the second tray <NUM> among the plurality of ice making cells 320a.

In addition, since ice attached to the first tray <NUM> may be easily separated from the first tray <NUM> due to the influence of gravity, the second reference time may be shorter than the first reference time. For example, the second reference time may be about <NUM> seconds.

After the ice separation heater <NUM> is turned off, the ice separation heater <NUM> may wait for a predetermined time so that the melting water by the ice separation heater <NUM> is cooled (S12).

When the water melting due to the heat of the ice separation heater <NUM> drops into the ice bin <NUM>, a mat of ice cubes may be generated inside the ice bin <NUM>, or the shape of the ice may be deformed due to the melting water. In order to prevent such a problem, after waiting for a predetermined time to cool the melting water, ice may be separated into the ice bin <NUM>.

The controller <NUM> may make the second tray <NUM> wait for a predetermined time (or waiting time) (S121). The waiting time may be a time sufficient for the melting water to cool and is preferably longer than the second reference time.

As an example, in a state in which the second tray <NUM> is in the additional heating position, the second tray <NUM> may wait for a predetermined time.

As another example, after the ice separation heater <NUM> additionally transfers heat to the second tray <NUM>, the controller <NUM> may also make the second tray <NUM> wait for a predetermined time at the specific position in which the second tray <NUM> is further moved in a forward direction. The specific position may be between the standby position and the ice separation position.

Through this, the ice inside the ice making cell 320a may not be separated into the ice bin <NUM> and cold air may be easily introduced into the ice making cell 320a.

When the waiting time has elapsed, the controller <NUM> may rotate the second tray <NUM> in a forward direction to move the second tray <NUM> to the ice separation position (S13).

Meanwhile, 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>, so that the extension part <NUM> passes through the communication hole 321e and presses the ice in the ice making cell 320a.

In this embodiment, in the ice separation process, the ice may be separated from the first tray <NUM> before the extension part <NUM> presses the ice. That is, ice may be separated from the surface of the first tray <NUM> by the heat of the ice separation heater <NUM>. In this case, the ice may move together with the second tray <NUM> in a state of being supported by the second tray <NUM>.

As another example, there may a case in which ice may not be separated from the surface of the first tray <NUM> even by the first and second heating of the ice separation heater <NUM>.

Accordingly, when the second tray <NUM> moves in the forward direction, there is a possibility that ice may be separated from the second tray <NUM> in a state in which the ice is in close contact with 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 presses the ice in close contact with the first tray <NUM>, so that the ice may be separated from the first tray <NUM>. Ice separated from the first tray <NUM> may be supported by the second tray <NUM>.

In a case in which ice moves together with the second tray <NUM> in a state of being supported by the second tray <NUM>, the ice can be separated from the second tray <NUM> by the own weight thereof even if no external force is applied to the second tray <NUM>.

In the process of moving the second tray <NUM>, even if ice does not fall from the second tray <NUM> due to the own weight thereof, when the second tray <NUM> is pressed by the second pusher <NUM> as illustrated in <FIG>, ice may be separated from the second tray <NUM> and fall downward.

Specifically, as illustrated in <FIG>, in a process in which the second tray <NUM> moves, the second tray <NUM> contacts the extension part <NUM> of the second pusher <NUM>.

When the second tray <NUM> continuously moves in the forward direction, the extension part <NUM> presses the second tray <NUM> to deform the second tray <NUM>, and the pressing force of the extension part <NUM> is transmitted to the ice so that the ice may be separated from the surface of the second tray <NUM>. Ice separated from the surface of the second tray <NUM> may fall down and be stored in the ice bin <NUM>.

In this embodiment, as illustrated in <FIG>, a position in which the second tray <NUM> is deformed by being pressed by the second pusher <NUM> may be referred to as an ice separation position.

In this embodiment, ice may be separated from the tray through two heating processes of the ice separation heater <NUM> and the first and second pushers in order to secure ice separation reliability of ice.

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.

For example, the full ice detection lever <NUM> rotates together with the second tray <NUM>, and the rotation of the full ice detection lever <NUM> is interrupted by ice while the full ice detection lever <NUM> rotates. In this case, it may be determined that the ice bin <NUM> is in a full ice state. On the other hand, if the rotation of the full ice detection lever <NUM> does not interfere with the ice while the full ice detection lever <NUM> rotates, it may be determined that the ice bin <NUM> is not in the full ice state.

After the ice is separated from the second tray <NUM>, the controller <NUM> controls the driver <NUM> to allow the second tray assembly <NUM> to move in the reverse direction (S14). Then, the second tray assembly <NUM> moves from the ice separation position to the water supply position.

When the second tray assembly <NUM> moves to the water supply position of <FIG>, the controller <NUM> stops the driver <NUM> (S1).

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.

Meanwhile, in this embodiment, the cooling power of the cold air supply part <NUM> may be determined in correspondence with the target temperature of the freezing compartment <NUM>. The cold air generated by the cold air supply part <NUM> may be supplied to the freezing compartment <NUM>.

Water in the ice making cell 320a may be phase-changed into ice by heat transfer of the cold air supplied to the freezing compartment <NUM> and the water in the ice making cell 320a.

In this embodiment, the heating amount of the transparent ice heater <NUM> for each unit height of water may be determined in consideration of a predetermined cooling power of the cold air supply part <NUM>.

The heating amount (or output) of the transparent ice heater <NUM> determined in consideration of the predetermined cooling power of the cold air supply part <NUM> is referred to as a reference heating amount (or reference output). The size of the reference heating amount per unit height of the water is different.

However, when the heat transfer amount between the cold air of the freezing compartment <NUM> and the water in the ice making cell 320a is varied, if the heating amount of the transparent ice heater <NUM> is not adjusted to reflect this, there is a problem that the transparency of ice for each unit height is changed.

In this embodiment, a case in which the heat transfer amount of cold air and water increases may be a case in which, for example, the cooling power of the cold air supply part <NUM> increases, or a case in which air having a temperature lower than the temperature of the cold air in the freezing compartment <NUM> is supplied to the freezing compartment <NUM>.

On the other hand, a case in which the heat transfer amount of cold air and water is reduced may be a case in which, for example, the cooling power of the cold air supply part <NUM> is reduced, a case in which the door is opened and air having the temperature which is higher than the temperature of the cold air in the freezing compartment <NUM> is supplied to the freezing compartment <NUM>, a case in which food having a temperature higher than the temperature of cold air in the freezing compartment <NUM> is put into the freezing compartment <NUM>, or a case in which a defrost heater (not illustrated) for defrosting the evaporator is turned on.

For example, in a case in which the target temperature of the freezing compartment <NUM> is lowered, the operating mode of the freezing compartment <NUM> is changed from the normal mode to the rapid cooling mode, the output of at least one of the compressor and the fan increases, or the opening degree of the refrigerant valve increases, the cooling power of the cold air supply part <NUM> may increases.

On the other hand, the target temperature of the freezing compartment <NUM> increases, the operating mode of the freezing compartment <NUM> is changed from the rapid cooling mode to the normal mode, the output of at least one of the compressor and the fan is reduced, or the opening degree of the refrigerant valve is reduced, the cooling power of the cold air supply part <NUM> may be reduced.

In a case in which the heat transfer amount of the cold air and water increases, the temperature of the cold air around the ice maker <NUM> decreases, thereby increasing the rate of ice generation.

Therefore, in this embodiment, in a case in which the heat transfer amount of cold air and water increases so that the ice making speed can be maintained within a predetermined range lower than the ice making speed when ice making is performed while the transparent ice heater <NUM> is turned off, the heating amount of the transparent ice heater <NUM> may be controlled to increase.

On the other hand, in a case where the heat transfer amount of the cold air and water is reduced, the heating amount of the transparent ice heater <NUM> may be controlled to be reduced.

Claim 1:
A method for controlling a refrigerator comprising a first tray (<NUM>) configured to form a portion of an ice making cell (320a), a second tray (<NUM>) configured to form the ice making cell (320a) together with the first tray (<NUM>), a driver (<NUM>) configured to move the second tray (<NUM>), and a heater (<NUM>) configured to supply heat to one or more of the first tray (<NUM>) and the second tray (<NUM>), wherein a direction in which the second tray (<NUM>) moves from an ice making position, to an ice standby position, to an ice separation position is forward, and a direction in which the second tray (<NUM>) moves from the ice separation position, to the water supply position, to the ice making position is reverse, the method comprising:
performing (S2) water supply of the ice making cell (320a) in a state in which the second tray (<NUM>) is moved to the water supply position;
performing (S4) ice making after the second tray (<NUM>) is moved (S3) from the water supply position to the ice making position in the reverse direction after the water supply is completed;
turning (S8) on the heater (<NUM>) when ice making is completed;
when a movement condition of the second tray (<NUM>) is satisfied:
- moving (S9) the second tray (<NUM>) to a standby position in the forward direction and turning off (S11) the heater (<NUM>) when a turn-off condition of the heater (<NUM>) is satisfied, only after the second tray (<NUM>) moves to the standby position, or
- turning off the heater (<NUM>) and then moving the second tray (<NUM>) to a standby position in the forward direction;
determining (S12) whether the heater (<NUM>) is turned off and a predetermined time has elapsed; and
moving (S13) the second tray (<NUM>) to the ice separation position in the forward direction when it is determined that the predetermined time has elapsed.