Patent Description:
Refrigerator appliances generally include a cabinet that defines one or more chilled chambers for receipt of food articles for storage. In addition, refrigerator appliances also generally include a door rotatably hinged to the cabinet to permit selective access to food items stored in chilled chamber(s). Certain refrigerator appliances include an icemaker. In order to produce ice, liquid water is directed to the icemaker and frozen. After being frozen, ice may be directed to a separate ice storage bin. In order to maintain ice in a frozen state, the icemaker and the ice storage bin may be positioned within a chilled chambers maintained at a temperature below the freezing point of water, e.g., such as in the freezer chamber or in a separate compartment behind one of the doors.

Conventional icemakers are positioned within a freezer chamber that has a temperature below the freezing point of water, e.g., such that cool air within the freezer chamber can freeze water dispensed into a plurality of ice molds and facilitate the ice making process. However, a common problem with such icemakers is ice buildup. For example, since the icemaker is much colder than the ice, moisture commonly sublimates from the ice and transfers to the icemaker mold. This develops ice buildup or frost on the icemaker. Ice buildup may require costly heating systems required to remove the ice buildup and may result in dispensing failures. Further, conventional icemakers require a water fill tube heater in order to prevent water within the water fill tube from freezing and clogging, potentially damaging the water fill tube or water supply system.

Accordingly, it would be advantageous to provide a refrigerator appliance with an improved ice making assembly that reduces frost buildup and includes feature(s) addressing one or more of the above identified issues.

<CIT> disclosed a refrigerator that including an ice making tray, a cooling system, a stirrer, at least a portion of which is submerged in the ice making tray, a stirring motor coupled to the stirrer, and a controller storing instructions and configured to execute the stored instructions to control the stirring motor to drive the stirrer while controlling the cooling system to cool water stored in the ice making tray.

<CIT> disclosed a control method of a refrigerator. The refrigerator includes an ice making chamber refrigerant pipe to supply a refrigerant to make ice in a direct cooling manner and an ice making chamber circulation fan to create a forced air stream to circulate air in the ice making chamber.

<CIT> disclosed a method of controlling temperature for forming ice within an icemaker compartment of a refrigerator. The method includes the steps of activating at least one of the compressor and the coolant pump during an icemaking cycle to provide cooling to the icemaker compartment sufficient to make ice at a first rate, and increasing operation of at least one of the compressor and the coolant pump to provide cooling to the icemaker compartment sufficient to make ice at a second rate, which is faster than the first rate.

As used herein, the term "or" is generally intended to be inclusive (i.e., "A or B" is intended to mean "A or B or both"). The terms "first," "second," and "third" may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms "upstream" and "downstream" refer to the relative flow direction with respect to fluid flow in a fluid pathway. For example, "upstream" refers to the flow direction from which the fluid flows, and "downstream" refers to the flow direction to which the fluid flows.

Referring now to the drawings, <FIG> provides a pair of refrigerator doors <NUM> in a closed position. Refrigerator appliance <NUM> includes a cabinet or housing <NUM> that extends between a top <NUM> and a bottom <NUM> along a vertical direction V. Cabinet <NUM> also extends along a lateral direction L and a transverse direction T, each of the vertical direction V, lateral direction L, and transverse direction T being mutually perpendicular to one another. Cabinet <NUM> defines one or more chilled chambers for receipt of food items for storage. In some embodiments, cabinet <NUM> defines a fresh food chamber or compartment <NUM> positioned at or adjacent top <NUM> of cabinet <NUM> and a freezer chamber or compartment <NUM> arranged at or adjacent bottom <NUM> of cabinet <NUM>. As such, refrigerator appliance <NUM> is generally referred to as a bottom mount refrigerator. It is recognized, however, that the benefits of the present disclosure apply to other types and styles of refrigerator appliances such as, for example, a top mount refrigerator appliance or a side-by-side style refrigerator appliance. Consequently, the description set forth herein is for illustrative purposes only and is not intended to be limiting in any aspect to any particular refrigerator chamber configuration.

Refrigerator doors <NUM> are rotatably hinged to an edge of cabinet <NUM> for selectively accessing fresh food chamber <NUM>. In some embodiments, a freezer door <NUM> is arranged below refrigerator doors <NUM> for selectively accessing freezer compartment <NUM>. Freezer door <NUM> may be coupled to a freezer drawer (not shown) slidably mounted within freezer compartment <NUM>. Refrigerator doors <NUM> and freezer door <NUM> are shown in the closed configuration in <FIG>.

In some embodiments, refrigerator appliance <NUM> includes a dispensing assembly <NUM> for dispensing liquid water or ice. Dispensing assembly <NUM> includes a dispenser <NUM> positioned on or mounted to an exterior portion of refrigerator appliance <NUM> (e.g., on one of doors <NUM>). Dispenser <NUM> includes a discharging outlet <NUM> for accessing ice and liquid water. An actuating mechanism <NUM>, shown as a paddle, is mounted below discharging outlet <NUM> for operating dispenser <NUM>. In alternative exemplary embodiments, another suitable actuator may be used to operate dispenser <NUM>. For example, dispenser <NUM> can include a sensor (such as an ultrasonic sensor) or a button rather than the paddle. A user interface panel <NUM> is provided for controlling the mode of operation. For example, user interface panel <NUM> includes a plurality of user inputs (not labeled), such as a water dispensing button and an ice-dispensing button, for selecting a desired mode of operation such as crushed or non-crushed ice.

Discharging outlet <NUM> and actuating mechanism <NUM> are an external part of dispenser <NUM> and are mounted in a dispenser recess <NUM>, as will be described in greater detail below. Generally, dispenser recess <NUM> defines a transverse opening <NUM> that extends in the vertical direction V from a top recess end <NUM> to a bottom recess end <NUM>, as well as in the lateral direction L from a first recess side <NUM> to a second recess side <NUM>. In certain embodiments, dispenser recess <NUM> is positioned at a predetermined elevation convenient for a user to access ice or water and enabling the user to access ice without the need to bend-over and without the need to open doors <NUM>. In optional embodiments, dispenser recess <NUM> is positioned at a level that approximates the chest level of a user.

Generally, operation of the refrigerator appliance <NUM> can be regulated by a controller <NUM> that is operatively coupled to user interface panel <NUM> or various other components, as will be described below. User interface panel <NUM> provides selections for user manipulation of the operation of refrigerator appliance <NUM>, such as selections between whole or crushed ice, chilled water, or other various options. In response to user manipulation of user interface panel <NUM> or one or more sensor signals, controller <NUM> may operate various components of the refrigerator appliance <NUM>. Controller <NUM> may include a memory and one or more microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of refrigerator appliance <NUM>. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controller <NUM> may be constructed without using a microprocessor (e.g., using a combination of discrete analog or digital logic circuitry-such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

Controller <NUM> may be positioned in a variety of locations throughout refrigerator appliance <NUM>. In the illustrated embodiment, controller <NUM> is located adjacent to or on user interface panel <NUM>. In other embodiments, controller <NUM> may be positioned at another suitable location within refrigerator appliance <NUM>, such as for example within a fresh food chamber, a freezer door, etc. Input/output ("I/O") signals may be routed between controller <NUM> and various operational components of refrigerator appliance <NUM>. For example, user interface panel <NUM> may be in operable communication (e.g., electrical communication) with controller <NUM> via one or more signal lines or shared communication busses.

Controller <NUM> may be operatively coupled with the various components of dispensing assembly <NUM> and may control operation of the various components. For example, the various valves, switches, etc. may be actuatable based on commands from controller <NUM>. As discussed, interface panel <NUM> may additionally be operatively coupled (e.g., via electrical or wireless communication) with controller <NUM>. Thus, the various operations may occur based on user input or automatically through controller <NUM> instruction.

<FIG> is a perspective view of refrigerator appliance <NUM> having refrigerator doors <NUM> in an open position to reveal the interior of the fresh food chamber <NUM> and <FIG> provides an exploded perspective view of an exemplary ice maker <NUM> of the refrigerator appliance <NUM>. As illustrated, refrigerator appliance <NUM> may include an ice making assembly or icemaker <NUM>, and an ice storage compartment <NUM>. Icemaker <NUM> may be provided within the fresh food chamber <NUM> and may be ambiently exposed within the fresh food chamber. In other words, icemaker <NUM> is not insulated from ambient air within the fresh food chamber <NUM>. More specifically, individual parts of icemaker <NUM> (which will be described below with reference to <FIG>), such as a mold body <NUM>, may be exposed within the fresh food compartment <NUM>. Icemaker <NUM> may be in any suitable location within fresh food compartment <NUM> such that ice may be formed and moved into ice storage compartment <NUM>. In one example, icemaker <NUM> is located in an upper left corner of fresh food compartment <NUM> when viewed from a front of refrigerator appliance <NUM>. As is understood, icemaker <NUM> may be used within any suitable refrigerator appliance, such as refrigerator appliance <NUM>.

Generally, icemaker <NUM> includes an ice mold or mold body <NUM> that extends between a first end portion <NUM> and a second end portion <NUM> (e.g., along a rotation axis AR). Mold body <NUM> defines multiple compartments (e.g., one or more first compartments <NUM> and one or more second compartments <NUM>) separated by one or more partitions walls for receipt of liquid water for freezing. The compartments <NUM>, <NUM> may be spaced apart from one another or distributed (e.g., along the rotation axis AR between first end portion <NUM> and second end portion <NUM>). Thus, a partition wall may be axially positioned between a first compartment <NUM> and a second compartment <NUM>.

Generally, icemaker <NUM> can receive liquid water (e.g., from a water connection to plumbing within a residence or business housing refrigerator appliance <NUM>) and direct such liquid water into mold body <NUM> (e.g., into compartments <NUM>, <NUM> of mold body <NUM>). Within compartments <NUM>, <NUM> of mold body <NUM>, liquid can freeze to form ice cubes. It is understood that the term "ice cube," as used herein, does not require a cubic geometry (i.e., six bounded square faces), but indicates a discrete unit of solid frozen ice generally having a predetermined three-dimensional shape.

As shown, a refrigerant line or refrigerant conduit <NUM> may run through icemaker <NUM>. For example, refrigerant line <NUM> is part of a sealed system or sealed refrigerant system to be described below. Accordingly, refrigerant cooled to a temperature below freezing may be cycled through icemaker <NUM> to produce the ice cubes (e.g., as illustrated schematically in <FIG>). Icemaker <NUM> may further include a heating element or heater <NUM> mounted to a lower portion <NUM> of mold body <NUM>. The heater <NUM> can be press-fit, stacked, or clamped into the lower portion <NUM> of the mold body <NUM>. The heater <NUM> may heat the icemaker <NUM> after a harvest cycle is performed. Alternatively, the heater <NUM> may heat the icemaker <NUM> when frost is detected on the icemaker <NUM>. In some embodiments, the heater <NUM> may heat the icemaker <NUM> during periods of non-use (e.g., when the ice storage compartment <NUM> is full). In some embodiments, the heater <NUM> may heat the icemaker <NUM> to assist in releasing ice cubes from the compartments <NUM>, <NUM> of the mold body <NUM>.

<FIG> is a cut away side view of an exemplary refrigerator appliance <NUM>. As seen in <FIG>, icemaker <NUM> and ice storage compartment <NUM> may be provided at or near a top of fresh food compartment <NUM> in the vertical direction V. Specifically, icemaker <NUM> may be provided above ice storage compartment <NUM>. As such, ice formed in icemaker <NUM> may be dropped downward in the vertical direction V into ice storage compartment <NUM>. In some embodiments, the ice storage compartment <NUM> is provided proximal to the icemaker <NUM> in either or both of the transverse direction T and the lateral direction L. The disclosure is not limited, however, and the ice storage compartment <NUM> and the icemaker <NUM> may be located in any suitable positions.

The ice storage compartment <NUM> may include a top or upper wall <NUM>. The upper wall <NUM> may be below the icemaker <NUM>. A supply opening <NUM> may be defined in the upper wall <NUM>. In some embodiments, the supply opening <NUM> is located beneath the icemaker <NUM>. As such, ice formed in the icemaker <NUM> may be dropped by gravity into the ice storage compartment <NUM>. According to alternative exemplary embodiments, icemaker <NUM> may be positioned at other suitable locations relative to the supply opening <NUM> and may include additional features for dispensing ice through the supply opening, e.g., such as an auger mechanism, an ice chute, or another suitable ice transfer or conveying mechanism.

The ice storage compartment <NUM> may include a bottom or lower wall <NUM>, provided beneath the upper wall <NUM>. Lower wall <NUM> may define a lower boundary of the ice storage compartment <NUM>. A dispenser opening <NUM> may be formed in the lower wall <NUM> of the ice storage compartment <NUM>. Ice cubes that are stored in the ice storage compartment <NUM> may be selectively released to dispenser <NUM> through the dispenser opening <NUM> according to a user input. A rear of the ice storage compartment <NUM> may be defined by a rear or side wall of the fresh food compartment <NUM>. A front of the ice storage compartment <NUM> may be defined by one of the refrigerator doors <NUM>. Alternatively, a separate front wall may be provided and attached to each of the upper wall <NUM> and the lower wall <NUM>.

The ice storage compartment <NUM> includes an insulated door <NUM>. The insulated door <NUM> selectively opens and closes the supply opening <NUM> in the upper wall <NUM>. In the invention, the insulated door <NUM> is attached to the ice storage compartment <NUM> in a sliding manner. In other words, the insulated door <NUM> slides in the transverse direction T to selectively open and close the supply opening <NUM>. Alternatively, the insulated door <NUM> may slide in the lateral direction L to selectively open and close the supply opening <NUM>. According to still other exemplary embodiments, insulated door <NUM> may include one or more resilient flaps that deflect as ice is dispensed and then spring back to insulate the ice storage compartment <NUM> from the fresh food compartment <NUM>. Other suitable means for insulating ice storage compartment <NUM> while also selectively permitting ice to enter ice storage compartment <NUM> are possible and within the scope of the present subject matter.

The insulated door <NUM> is configured to slide along an interior of the ice storage compartment <NUM>. In other words, the insulated door <NUM> is slidably attached to an under surface of the upper wall <NUM>. Accordingly, when a harvest cycle is executed (e.g., when ice cubes are moved from the icemaker <NUM> into the ice storage compartment <NUM>), the insulated door <NUM> may be slid in the transverse direction T along an interior of the ice storage compartment <NUM>. In some embodiments, the insulated door <NUM> may be slid in the lateral direction L when a harvest cycle is executed. The insulated door is slidably provided on a top surface of upper wall <NUM>. In other words, when a harvest cycle is executed, the insulated door <NUM> may be slid in the transverse direction T along a top surface of upper wall <NUM> to open the supply opening <NUM>.

The refrigerator appliance <NUM> may include a drive mechanism <NUM> configured to selectively move the insulated door <NUM> between an opened position and a closed position. The drive mechanism <NUM> may include a motor. The motor may be any suitable motor. In one example, the motor is a servo motor. The drive mechanism <NUM> may further include a transmission. The transmission may convert power generated by the motor into linear movement of the door. In one example, the transmission is a slide and roller combination.

An ice storage bucket <NUM> may be provided in the ice storage compartment <NUM>. The ice storage bucket <NUM> may be a separate bucket or container configured to hold the ice cubes that are formed in the icemaker <NUM> and dropped into ice storage compartment <NUM>. The ice storage bucket <NUM> may be a conventional ice storage bucket. For example, the ice storage bucket includes a dispenser motor <NUM>. The dispenser motor <NUM> may drive an auger configured to selectively release ice cubes from the ice storage bucket <NUM> to the dispenser <NUM>.

Refrigerator appliance <NUM> may include a cooling system for maintaining a suitable temperature within ice storage compartment. For example, according to an exemplary embodiment of the refrigerator appliance <NUM>, the freezer compartment <NUM> may be provided below the fresh food compartment <NUM>. In order to supply chilled air to the ice storage compartment <NUM>, the refrigerator appliance <NUM> according to the exemplary embodiment may include a fan <NUM> for circulating chilled air from the freezer compartment <NUM> to the ice storage compartment <NUM>. In one example, the fan <NUM> is a centrifugal fan. However, the fan <NUM> may be any suitable fan capable of circulating air. The refrigerator appliance <NUM> includes an air supply duct <NUM>. The air supply duct <NUM> fluidly connects the freezer compartment <NUM> with the ice storage compartment <NUM>. For example, the air supply duct <NUM> passes through a side wall of the cabinet <NUM>. In alternative embodiments, the air supply duct <NUM> passes through an interior of fresh food compartment <NUM>. The fan <NUM> may be located at an inlet of the air supply duct <NUM> in the freezer compartment <NUM>. An outlet of the air supply duct <NUM> may be provided at a top of the air supply duct <NUM>. The outlet of the air supply duct <NUM> is in fluid communication with the ice storage compartment <NUM>. Chilled air from the freezer compartment <NUM> is exhausted into the ice storage compartment <NUM> via the outlet of the air supply duct <NUM>.

The refrigerator appliance <NUM> according to the invention further includes an air return duct <NUM>. The air return duct <NUM> fluidly connects the freezer compartment <NUM> with the ice storage compartment <NUM>. For example, the air return duct <NUM> passes through a side wall of the cabinet <NUM>. In alternative embodiments, the air return duct <NUM> passes through an interior of fresh food compartment <NUM>. An inlet of the air return duct <NUM> may be provided at a top of the air return duct <NUM>. The inlet of the air return duct <NUM> is in fluid communication with the ice storage compartment <NUM>. An outlet of the air return duct <NUM> may be provided at a bottom of the air return duct <NUM>. The outlet of the air return duct <NUM> is in fluid communication with the freezer compartment <NUM>. Thus, chilled air may be circulated from the freezer compartment <NUM> through the air supply duct <NUM>, into the ice storage compartment <NUM>, through the air return duct <NUM>, and back into the freezer compartment <NUM> by operation of the fan <NUM>. Although the cooling system described above relies on forced convection through ducts that fluidly couple the ice storage compartment <NUM> and the freezer compartment, it should be appreciated that any other suitable system for cooling ice storage compartment may be used according to alternative embodiments.

Refrigerator appliance <NUM> may further include systems for detecting a level of ice, e.g., to help determine when ice production may stop, when ice harvest may occur, etc. For example, the refrigerator appliance <NUM> according to an exemplary embodiment may further include a sensor <NUM> configured to sense a level of ice stored in the ice storage compartment <NUM>. The sensor <NUM> may be any suitable sensor able to detect an amount of ice stored in the ice storage compartment <NUM>, such as an optical sensor, an infrared sensor, an acoustic sensor, etc. For example, the sensor <NUM> may be an infrared sensor. The sensor <NUM> may be provided in the ice storage compartment <NUM>. In one example, the sensor is provided in the ice storage bucket <NUM> within the ice storage compartment <NUM>. The sensor <NUM> may be operably connected to the controller <NUM>. The sensor <NUM> may send signals relating to a level of ice within the ice storage compartment <NUM> to the controller <NUM>. Although the ice level detection system is described herein as a sensor, it should be appreciated that any other suitable means for detecting ice level may be used according to alternative embodiments, such as a mechanical ice level arm.

<FIG> illustrates a schematic view of a sealed refrigerant system <NUM> that is generally configured for executing a vapor compression cycle. According to <FIG>, a sealed refrigerant system, or sealed system <NUM> may circulate a refrigerant via a refrigerating conduit <NUM>. The sealed system may include a compressor <NUM>, a condenser <NUM>, an expansion device <NUM>, and an evaporator <NUM>. Each of the compressor <NUM>, condenser <NUM>, expansion device <NUM>, and evaporator <NUM> may be fluidly connected to one another by the refrigerating conduit or first refrigerating conduit <NUM>. The evaporator <NUM> may be provided in the freezer compartment <NUM> and may be configured to cool air within the freezer compartment <NUM>.

Within sealed system <NUM>, gaseous refrigerant flows into compressor <NUM>, which operates to increase the pressure of the refrigerant. This compression of the refrigerant raises its temperature, which is lowered by passing the gaseous refrigerant through condenser <NUM>. Within condenser <NUM>, heat exchange with ambient air takes place so as to cool the refrigerant and cause the refrigerant to condense to a liquid state.

Expansion device <NUM> (e.g., a mechanical valve, capillary tube, electronic expansion valve, or other restriction device) receives liquid refrigerant from condenser <NUM>. From expansion device <NUM>, the liquid refrigerant enters evaporator <NUM>. Upon exiting expansion device <NUM> and entering evaporator <NUM>, the liquid refrigerant drops in pressure and vaporizes. Due to the pressure drop and phase change of the refrigerant, evaporator <NUM> is cool relative to freezer compartment <NUM>. As such, cooled water and ice or air is produced and refrigerates icemaker <NUM> or freezer compartment <NUM>. Thus, evaporator <NUM> is a heat exchanger which transfers heat from water or air in thermal communication with evaporator <NUM> to refrigerant flowing through evaporator <NUM>.

The sealed refrigerant system <NUM> may include a three-way valve <NUM> operably coupled to the refrigerant conduit <NUM> between the evaporator <NUM> and the icemaker <NUM>. The three-way valve <NUM> may be selectively opened to allow refrigerant to circulate through the icemaker <NUM>. The controller <NUM> may control an opening and closing of the three-way valve <NUM> to allow the refrigerant to circulate through the icemaker <NUM>. The three-way valve <NUM> may be any suitable valve capable of selectively opening and closing a bypass passageway <NUM>. For example, the three-way valve <NUM> may have one inlet and two outlets, and the controller <NUM> may control one outlet to be open at a time. As such, refrigerant may either circulate through the refrigerant conduit <NUM> or through the bypass passageway <NUM>.

According to one example, the controller <NUM> may control the three-way valve <NUM> to close the bypass passageway <NUM> to allow refrigerant to circulate through the icemaker <NUM>. In this manner, icemaker <NUM> is supplied with refrigerant to form ice cubes. According to another example, the controller <NUM> may control the three-way valve <NUM> to open the bypass passageway <NUM> to restrict refrigerant from circulating through the icemaker <NUM>. In this manner, no refrigerant is supplied to the icemaker <NUM>. Consequently, because the icemaker <NUM> is provided in the fresh food compartment <NUM>, which is maintained at a temperature above freezing, frost formed on an outside of the icemaker <NUM> may melt off, preventing malfunction or failure of the icemaker <NUM>.

The refrigerator appliance <NUM> according to an exemplary embodiment may further include a drain pan or drain conduit <NUM>. The drain conduit <NUM> may be provided beneath the icemaker <NUM> and may collect condensate or melt water from the icemaker <NUM>. Melt water may be formed as frost on the icemaker <NUM> melts when the icemaker <NUM> is in an inactive state (e.g., no refrigerant is being cycled to the icemaker <NUM>). In other words, when the three-way valve <NUM> is closed (i.e., refrigerant is circulated through the bypass passageway <NUM>), frost on the icemaker <NUM> melts due to exposure to air that is above freezing within the fresh food compartment <NUM>. The drain conduit <NUM> may be a pan located beneath the icemaker <NUM>. The drain conduit <NUM> may then guide melt water to an outside of the refrigerator appliance <NUM> or to any other suitable collection container or reservoir.

<FIG> illustrates another exemplary embodiment of the refrigerator appliance <NUM>. Due to the similarities between embodiments described herein, like reference numerals may be used to refer to the same or similar features. According to this embodiment, the sealed system <NUM> includes a first sealed system <NUM> and a second sealed system <NUM>. The first sealed system <NUM> may include the compressor <NUM>, the condenser <NUM>, the expansion device <NUM>, and the evaporator <NUM>, all in fluid communication with each other through the refrigerant conduit <NUM>. The operation of these elements is described above; thus, a repeat detailed description is omitted. The refrigerant conduit <NUM> may also pass through a heat exchanger <NUM>. The heat exchanger <NUM> may be a heat exchanger configured to exchange heat between two sealed systems. For example, the heat exchanger <NUM> is a liquid-to-liquid heat exchanger.

The second sealed system <NUM> may include a pump <NUM> and a second refrigerant conduit <NUM>. The pump <NUM> may be a fluid pump configured to circulate a refrigerant through the second refrigerant conduit <NUM>. The second refrigerant conduit <NUM> may pass through the heat exchanger <NUM>. The second refrigerant conduit <NUM> may pass through the icemaker <NUM>. The second refrigerant conduit <NUM> may exchange heat with the first refrigerant conduit <NUM> within the heat exchanger <NUM>. The cooled refrigerant may then be circulated through the icemaker <NUM> by the pump <NUM>. The refrigerant circulated through second refrigerant conduit <NUM> may be any suitable refrigerant capable of retaining and distributing heat. For example, the refrigerant circulated through the second refrigerant conduit <NUM> may be a water/glycol brine solution. Additionally, or alternatively, a propylene glycol, ethylene glycol, or antifreeze solution may be used.

<FIG> illustrates the various insulated walls, mullions, partitions, or other insulated structures within cabinet <NUM> of refrigerator appliance <NUM>. For clarity, the insulated structures are illustrated here using cross hatching. Specifically, as illustrated, the ice storage compartment <NUM> may be located in the fresh food compartment <NUM> of the exemplary refrigerator appliance <NUM>. The ice storage compartment <NUM> may be insulated from the fresh food compartment <NUM>. For instance, upper wall <NUM> may have a first insulation <NUM>. First insulation <NUM> may be an insulated coating provided over the upper wall <NUM>. In one example, the upper wall <NUM> may be coated in a foam insulation spray. In another example, the upper wall <NUM> may define an inner volume filled with insulation.

Similarly, the lower wall <NUM> may have a second insulation <NUM>. Second insulation <NUM> may be an insulated coating provided over the lower wall <NUM>. In one example, the lower wall <NUM> may be coated in a foam insulation spray. In another example, the lower wall <NUM> may define an inner volume filled with insulation. The insulated door <NUM> may have a third insulation <NUM>. Third insulation <NUM> may be an insulated coating provided over the insulated door <NUM>. In one example, the insulated door <NUM> may be coated in a foam insulation spray. In another example, the insulated door <NUM> may define an inner volume filled with insulation.

Referring to <FIG>, a method of operating an exemplary refrigerator appliance <NUM> will be described. The sealed system <NUM> may be operated by driving the compressor <NUM> to circulate a refrigerant through the icemaker <NUM>. At this time, the three-way valve <NUM> is in an open position (e.g., the bypass passageway <NUM> is closed). As the chilled refrigerant is circulated through the icemaker <NUM>, ice cubes may be formed in icemaker <NUM>. Once the controller <NUM> determines that the ice cubes have been formed and that a harvest cycle is ready to be performed, the controller <NUM> may activate the drive mechanism <NUM> to open the insulated door <NUM>. Once the insulated door <NUM> is in the opened position, the ice cubes may be harvested from the icemaker <NUM> (e.g., the ice cubes are dropped into the ice storage compartment <NUM> through the supply opening <NUM>).

While the ice cubes are being harvested from the icemaker <NUM>, the controller <NUM> may turn off the fan <NUM>. Accordingly, cool air from the freezer compartment <NUM> may not be supplied to the ice storage compartment <NUM> during a harvesting of the ice cubes. This prevents an unwanted cooling of the fresh food compartment <NUM> when the insulated door <NUM> is in the opened position. Simultaneously, the controller <NUM> may switch the three-way valve <NUM> to a closed position (e.g., the bypass passageway <NUM> is opened). Thus, the refrigerant may not be circulated through the icemaker <NUM> during a harvesting of the ice cubes. This prevents frost from forming on the icemaker <NUM> due to sublimation of moisture from the ice cubes and/or cool air within the ice storage compartment <NUM>.

After the ice cubes have been harvested (e.g., moved from the icemaker <NUM> to the ice storage compartment <NUM>), the controller <NUM> may activate the drive mechanism to move the insulated door <NUM> to the closed position (e.g., close the supply opening <NUM>). The controller <NUM> may then switch the three-way valve <NUM> to the open position (e.g., close the bypass passageway <NUM>). Accordingly, refrigerant may flow through the icemaker <NUM> to reinstitute an icemaking operation. Sensor <NUM> may then sense an amount of ice in the ice storage compartment <NUM>. When the sensor <NUM> senses that an amount of ice is above a first predetermined amount, the controller <NUM> may switch the three-way valve to the closed position (e.g., open the bypass passageway <NUM>). The first predetermined amount may signify that the ice storage compartment <NUM> is substantially full. Thus, refrigerant is not circulated through the icemaker <NUM>. Accordingly, frost accumulated on the icemaker <NUM> may be melted due to a position of the icemaker <NUM> in the fresh food compartment <NUM> and subsequent exposure to an above freezing atmosphere.

According to some embodiments, when the sensor <NUM> senses that an amount of ice is above the first predetermined amount, the controller <NUM> may switch the pump <NUM> to an off position. Thus, refrigerant in the second refrigerant conduit <NUM> may be prevented from circulating through icemaker <NUM>. Accordingly, frost accumulated on the icemaker <NUM> may be melted due to a position of the icemaker <NUM> in the fresh food compartment <NUM> and subsequent exposure to an above freezing atmosphere.

The sensor <NUM> may continue to sense an amount of ice in the ice storage compartment <NUM>. When the level of ice sensed by the sensor <NUM> drops below a second predetermined level lower than the first predetermined level, the controller <NUM> may switch the three-way valve <NUM> to the open position (e.g., close the bypass passageway <NUM>). For example, the second predetermined level may signify that the ice storage compartment <NUM> is approximately half full. In some embodiments, the first predetermined level and the second predetermined level may be the same. Thus, refrigerant may be circulated through the icemaker <NUM> to again reinstitute the icemaking operation. The method may be repeated as necessary to maintain a usable amount of ice in the ice storage compartment <NUM>.

In an alternate embodiment, when the level of ice sensed by the sensor <NUM> drops below a second predetermined level lower than the first predetermined level, the controller <NUM> may switch the pump <NUM> to an on position. Thus, refrigerant in the second refrigerant conduit <NUM> may be circulated through the icemaker <NUM> to again reinstitute the icemaking operation. The method may be repeated as necessary to maintain a usable amount of ice in the ice storage compartment <NUM>.

Turning now to <FIG>, a method <NUM> of operating a refrigerator appliance according to an embodiment of the present disclosure will be described (e.g., as or as part of a harvesting and/or storing operation). The refrigerator appliance <NUM> may be one of the exemplary refrigerator appliances described above, and as such, a detailed description will be omitted.

As shown at <NUM>, the method <NUM> includes operating the sealed refrigerant system <NUM> to cool the icemaker <NUM> and form ice. As described above, the operation of the sealed refrigerant system <NUM> includes operating the compressor <NUM> to circulate a refrigerant. At this time, three-way valve <NUM> is in the open position (e.g., refrigerant is circulating through icemaker <NUM>).

At <NUM>, the method <NUM> includes determining that ice is ready to be harvested from the icemaker <NUM>. The controller <NUM> may determine that ice cubes have been formed and sufficiently frozen within icemaker <NUM> such that they may be moved or dropped into the ice storage compartment <NUM>. The controller <NUM> may use a variety of means to determine that the ice is ready to be harvested, such as a timer or a sensor. Upon detection that ice is ready to be harvested, the method <NUM> may proceed to <NUM>.

At <NUM>, the method <NUM> turns off the fan <NUM> and closes the three-way valve <NUM> (e.g., refrigerant is not circulating through icemaker <NUM>). The controller <NUM> may send a signal to stop the fan <NUM> from circulating air from freezing compartment <NUM> into ice storage compartment <NUM>. Thus, cool air from freezing compartment <NUM> is not supplied to ice storage compartment <NUM>. This may prevent unwanted cooling of fresh food compartment <NUM> and may limit sublimation of moisture from the ice cubes in ice storage compartment <NUM> to icemaker <NUM>. Likewise, the controller <NUM> may activate the three-way valve <NUM> to stop a flow of the refrigerant to the icemaker <NUM>. Thus, icemaker <NUM> is not cooled while the ice is ejected from the icemaker <NUM> into the ice storage compartment <NUM>.

At <NUM>, the method <NUM> opens the insulated door <NUM>. The controller <NUM> may send a signal to drive mechanism <NUM> to move the insulated door <NUM> from a closed position to an open position. As such, an interior of ice storage compartment <NUM> is exposed to the fresh food compartment <NUM> such that the ice cubes may be dropped into the ice storage compartment <NUM>. At <NUM>, ice is then harvested from icemaker <NUM> and dropped into ice storage compartment <NUM>.

At <NUM>, the method <NUM> includes determining whether the harvesting is complete. The refrigerator appliance <NUM> may include sensors configured to detect whether the harvesting is complete, such as rotation sensors or infrared sensors on the icemaker <NUM>. Is the harvesting is determined to be complete, the method <NUM> moves to <NUM>.

At <NUM>, the method <NUM> includes determining if an amount of ice in the ice storage compartment <NUM> is above a predetermined amount. The method <NUM> may refer to sensor <NUM> described above to determine an amount of ice in the ice storage compartment <NUM>. If the amount is above the predetermined amount, the method <NUM> proceeds to <NUM>. At <NUM>, the method <NUM> includes closing the insulated door <NUM>, switching the fan <NUM> to the on state, and maintaining the three-way valve <NUM> in the closed state. As such, the icemaker <NUM> is not supplied with refrigerant and thus may defrost. Further, cool air is supplied to the ice storage compartment <NUM> to maintain the ice in a frozen state. If the amount is below the predetermined amount, the method <NUM> proceeds to <NUM>.

At <NUM>, the method <NUM> includes closing insulated door <NUM> and opening three-way valve <NUM>. Once insulated door <NUM> is closed and three-way valve <NUM> is opened, an icemaking operation may begin again. The method <NUM> may be repeated as necessary to continually make and harvest ice up to the predetermined amount. Further, sensor <NUM> may continually determine an amount of ice in ice storage compartment <NUM> to determine whether or not to open three-way valve <NUM> to circulate refrigerant to icemaker <NUM> and perform the icemaking operation.

Claim 1:
A refrigerator appliance (<NUM>), comprising:
a fresh food compartment (<NUM>);
an ice storage compartment (<NUM>) positioned within the fresh food compartment (<NUM>) and being insulated from the fresh food compartment (<NUM>);
a sealed system (<NUM>) comprising a condenser (<NUM>), an expansion device (<NUM>), and an evaporator (<NUM>) fluidly coupled through a refrigerant conduit (<NUM>), and a compressor (<NUM>) operably coupled to the refrigerant conduit (<NUM>) for circulating a flow of refrigerant through the refrigerant conduit (<NUM>);
an icemaker (<NUM>) positioned in the fresh food compartment (<NUM>) above the ice storage compartment (<NUM>) and comprising an ice mold for receiving water, wherein the sealed system (<NUM>) is in direct thermal communication with the ice mold for cooling the ice mold to form ice from the water; and
a freezer compartment (<NUM>) adjacent to the fresh food compartment (<NUM>);
characterized in that, further comprising an air supply duct (<NUM>) through which air is supplied from the freezer compartment (<NUM>) to the ice storage compartment (<NUM>), and an air return duct (<NUM>) through which air is returned from the ice storage compartment (<NUM>) to the freezer compartment (<NUM>); and
an insulated door (<NUM>) positioned over an opening (<NUM>) in the ice storage compartment (<NUM>), the insulated door (<NUM>) being movable between an open position and a closed position to permit the ice to pass into the ice storage compartment (<NUM>) from the icemaker (<NUM>);
wherein the ice storage compartment (<NUM>) is defined at least in part by an upper wall (<NUM>) and a lower wall (<NUM>), and wherein the opening (<NUM>) is defined in the upper wall (<NUM>), the insulated door (<NUM>) is slidably attached to the under surface of the upper wall (<NUM>).