Patent Description:
Certain refrigerator appliances include an ice maker. An ice maker may also be a stand-alone appliance designed for use in commercial and/or residential kitchens. To produce ice, liquid water is directed to the ice maker and frozen. A variety of ice types can be produced depending upon the particular ice maker used. For example, certain ice makers include a mold body for receiving liquid water. The shape of the ice produced in such ice makers will generally correspond to the shape of the mold body. For example, refrigerator ice makers and other residential ice makers commonly include a mold body which produces crescent-shaped ice. Typical ice makers also generally produce ice which can be cloudy or opaque.

For instance <CIT> discloses an ice ball forming apparatus, comprising: an ice supply unit; a ball forming unit; and an ice ball discharging unit in order to manufacture and supply ice balls in large quantities.

Many consumers, however, prefer barrel ice, which may be generally cylindrical in shape, over crescent-shaped ice pieces. In addition, many consumers prefer clear ice over cloudy or opaque ice. However, ice makers which make barrel ice generally do not include features for providing clear ice, whereas ice makers which make clear ice generally do not include features for providing barrel-shaped ice.

Accordingly, an ice maker with features for producing ice which is clear and barrel-shaped would be useful.

Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention. The invention is defined by the claims, wherein independent claim <NUM> defines the invention and the dependent claims <NUM> through <NUM> define preferred embodiments thereof.

As part of an exemplary embodiment, an ice maker is provided. The ice maker defines a vertical direction, a lateral direction, and a transverse direction. The vertical, lateral, and transverse directions are mutually perpendicular. The ice maker includes a mold body. A plurality of mold cavities are defined in the mold body. Each mold cavity of the plurality of mold cavities extends between a floor and an opening along a longitudinal axis. Each mold cavity of the plurality of mold cavities is enclosed by at least one sidewall between the floor and the opening. The longitudinal axis of each mold cavity is oriented generally along the vertical direction The ice maker also includes a heater in thermal communication with the floor of each mold cavity of the plurality of mold cavities. The heater is configured to maintain water within a lower portion of each mold cavity in a liquid state. The ice maker further includes a drain conduit in fluid communication with the mold body and configured to receive a flow of liquid water from the mold cavities.

In an exemplary embodiment, a refrigerator appliance is provided. The refrigerator appliance includes a cabinet that defines a chilled chamber and an ice maker in thermal communication with the chilled chamber. The ice maker defines a vertical direction, a lateral direction, and a transverse direction. The vertical, lateral, and transverse directions are mutually perpendicular. The ice maker includes a mold body. A plurality of mold cavities are defined in the mold body. Each mold cavity of the plurality of mold cavities extends between a floor and an opening along a longitudinal axis. Each mold cavity of the plurality of mold cavities is enclosed by at least one sidewall between the floor and the opening. The longitudinal axis of each mold cavity is oriented generally along the vertical direction. The ice maker also includes a heater in thermal communication with the floor of each mold cavity of the plurality of mold cavities. The heater is configured to maintain water within a lower portion of each mold cavity in a liquid state. The ice maker further includes a drain conduit in fluid communication with the mold body and configured to receive a flow of liquid water from the mold cavities.

In an unclaimed method, a method of making clear ice in a refrigerator appliance is provided. The refrigerator appliance includes a cabinet defining a chilled chamber. The method includes filling a plurality of mold cavities in a mold body of an ice maker with liquid water and directing a flow of chilled air from the chilled chamber of the refrigerator towards openings of the plurality of mold cavities. As a result, the liquid water in an upper portion of each of the plurality of mold cavities freezes from the top down, such that clear ice barrels are formed. The method also includes activating a heater in the mold body of the ice maker during the step of directing the flow of chilled air. The heater is in thermal communication with a floor of each mold cavity of the plurality of mold cavities, such that the liquid water in a lower portion of each of the plurality of mold cavities is maintained in a liquid state. The method further includes draining at least a portion of the liquid water from the mold body of the ice maker with a drain conduit.

As used herein, terms of approximation such as "generally," "about," or "approximately" include values within ten percent greater or less than the stated value. When used in the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction, e.g., "generally vertical" includes forming an angle of up to ten degrees in any direction, e.g., clockwise or counterclockwise, with the vertical direction V.

<FIG> provides a perspective view of a refrigerator appliance <NUM> according to an exemplary embodiment of the present subject matter. Refrigerator appliance <NUM> includes a cabinet or housing <NUM> that generally defines a vertical direction V, a lateral direction L, and a transverse direction T, each of which is mutually perpendicular, such that an orthogonal coordinate system is generally defined. The cabinet <NUM> extends between a top <NUM> and a bottom <NUM> along the vertical direction V, between a left side <NUM> and a right side <NUM> along the lateral direction L, and between a front <NUM> and a rear <NUM> along the transverse direction T. Housing <NUM> defines chilled chambers for receipt of food items for storage. In particular, housing <NUM> defines fresh food chamber <NUM> positioned at or adjacent top <NUM> of housing <NUM> and a freezer chamber <NUM> arranged at or adjacent bottom <NUM> of housing <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, e.g., a top mount refrigerator appliance, a side-by-side style refrigerator appliance or a standalone ice maker 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 housing <NUM> for selectively accessing fresh food chamber <NUM>, e.g., at the left side <NUM> and the right side <NUM>. In addition, a freezer door <NUM> is arranged below refrigerator doors <NUM> for selectively accessing freezer chamber <NUM>. Freezer door <NUM> is coupled to a freezer drawer (not shown) mounted within freezer chamber <NUM> and slidable along the transverse direction T. Refrigerator doors <NUM> and freezer door <NUM> are shown in the closed configuration in <FIG>.

Refrigerator appliance <NUM> also includes a dispensing assembly <NUM> for dispensing liquid water and/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/or liquid water. An actuating mechanism <NUM>, shown as a paddle, is mounted below discharging outlet <NUM> for operating dispenser <NUM>. In alternative exemplary embodiments, any suitable actuating mechanism 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>. 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 the exemplary embodiment, dispenser recess <NUM> is positioned at a level that approximates the chest level of a user.

<FIG> provides a perspective view of a door of refrigerator doors <NUM>. Refrigerator appliance <NUM> includes a sub-compartment <NUM> defined on refrigerator door <NUM>. Sub-compartment <NUM> may be referred to as an "icebox. " Sub-compartment <NUM> extends into fresh food chamber <NUM> when refrigerator door <NUM> is in the closed position. As shown in <FIG> and discussed in greater detail below, an ice maker or ice making assembly <NUM> and an ice storage bin <NUM> may be positioned or disposed within sub-compartment <NUM>. Thus, ice is supplied to dispenser recess <NUM> (<FIG>) from the ice maker <NUM> and/or ice storage bin <NUM> in sub-compartment <NUM> on a back side of refrigerator door <NUM>. Chilled air from a sealed system (not shown) of refrigerator appliance <NUM> may be directed into components within sub-compartment <NUM>, e.g., ice maker <NUM> and/or ice storage bin <NUM>. As mentioned above, the present disclosure may also be applied to other types and styles of refrigerator appliances such as, e.g., a top mount refrigerator appliance, a side-by-side style refrigerator appliance or a standalone ice maker appliance. Accordingly, the description herein of the icebox <NUM> on the door <NUM> of the fresh food chamber <NUM> is by way of example only. In other example embodiments, the ice maker <NUM> may be positioned in the freezer chamber <NUM>, e.g., of the illustrated bottom-mount refrigerator, a side by side refrigerator, a top-mount refrigerator, or any other suitable refrigerator appliance. As another example, the ice maker <NUM> may also be provided in a standalone icemaker appliance.

An access door <NUM> is hinged to refrigerator door <NUM>. Access door <NUM> permits selective access to sub-compartment <NUM>. Any manner of suitable latch <NUM> is configured with sub-compartment <NUM> to maintain access door <NUM> in a closed position. As an example, latch <NUM> may be actuated by a consumer in order to open access door <NUM> for providing access into sub-compartment <NUM>. Access door <NUM> can also assist with insulating sub-compartment <NUM>, e.g., by thermally isolating or insulating sub-compartment <NUM> from fresh food chamber <NUM>.

<FIG> provides an elevation view of refrigerator door <NUM> with access door <NUM> shown in an open position. As may be seen in <FIG>, ice maker <NUM> is positioned or disposed within sub-compartment <NUM>. Ice maker <NUM> includes a mold body or casing <NUM>. As described in more detail below, a motor <NUM> is mounted within sub-compartment <NUM>, and is in mechanical communication with (e.g., coupled to) an ejector assembly for ejecting ice from the mold body <NUM>. An ice bucket or ice storage bin <NUM> is positioned proximate the mold body <NUM> and receives the ice after the ice is ejected from the mold body <NUM>. From ice storage bin <NUM>, the ice can enter dispensing assembly <NUM> and be accessed by a user as discussed above. In such a manner, ice maker <NUM> can produce or generate ice.

Ice maker <NUM> also includes a fan <NUM>. Fan <NUM> is configured for directing a flow of chilled air towards mold body <NUM>. As an example, fan <NUM> can direct chilled air from an evaporator of a sealed system through a duct to mold body <NUM>. Thus, mold body <NUM> can be cooled with chilled air from fan <NUM> such that ice maker <NUM> is air cooled in order to form ice therein. In some embodiments, e.g., as illustrated in <FIG>, the fan <NUM> may be located within the sub-compartment <NUM>. In other embodiments, the location of the fan <NUM> may vary, for example, the fan <NUM> may be located in a mechanical compartment with the sealed system, e.g., proximate to the evaporator. Ice maker <NUM> also includes a harvest heater <NUM>, such as an electric resistance heating element, mounted to or otherwise in thermal communication with mold body <NUM>. Harvest heater <NUM> is configured for selectively heating mold body <NUM>, e.g., to assist in ejecting ice from the mold body <NUM>.

Operation of ice maker <NUM> is controlled by a processing device or controller <NUM>, e.g., that may be operatively coupled to control panel <NUM> for user manipulation to select features and operations of ice maker <NUM>. Controller <NUM> can operate various components of ice maker <NUM> to execute selected system cycles and features. For example, controller <NUM> is in operative communication with motor <NUM>, fan <NUM> and heater <NUM>. Thus, controller <NUM> can selectively activate and operate motor <NUM>, fan <NUM> and heater <NUM>.

Controller <NUM> may include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with operation of ice maker <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 and/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. Motor <NUM>, fan <NUM> and heater <NUM> may be in communication with controller <NUM> via one or more signal lines or shared communication busses. It should be noted that controllers <NUM> as disclosed herein are capable of and may be operable to perform any methods and associated method steps as disclosed herein.

Ice maker <NUM> also includes a temperature sensor <NUM>. Temperature sensor <NUM> is configured for measuring a temperature of mold body <NUM> and/or liquids, such as liquid water, within mold body <NUM>. Temperature sensor <NUM> can be any suitable device for measuring the temperature of mold body <NUM> and/or liquids therein. For example, temperature sensor <NUM> may be a thermistor or a thermocouple or a bimetal thermostat. Controller <NUM> can receive a signal, such as a voltage or a current, from temperature sensor <NUM> that corresponds to the temperature of the mold body <NUM> and/or liquids therein. In such a manner, the temperature of mold body <NUM> and/or liquids therein can be monitored and/or recorded with controller <NUM>. Some embodiments can also include an electromechanical icemaker configured with a bimetal thermostat to complete an electrical circuit when a specific temperature is reached. By completion of the circuit, the heater <NUM> and ejector mechanism would be activated via electrical powering of the motor <NUM>.

<FIG> provides a perspective view of the ice maker <NUM>. The ice maker <NUM> defines a vertical direction VI, a lateral direction LI, and a transverse direction TI. In exemplary embodiments wherein the ice maker <NUM> is installed in a refrigerator appliance <NUM>, the ice maker <NUM> may be installed such that the vertical direction VI of the ice maker <NUM> generally corresponds to the vertical direction V of the cabinet <NUM>. As noted above, terms of approximation such as "generally" or "about" are used herein to include within ten percent greater or less than the stated value. In the context of an angle or direction, such terms include within ten degrees greater or less than the stated angle or direction. For example, the ice maker <NUM> may be installed such that the vertical direction VI of the ice maker <NUM> generally corresponds to the vertical direction V of the cabinet <NUM> when the vertical direction VI is aligned with, or within ten degrees in any direction of, the vertical direction V.

As may be seen in <FIG>, the mold body <NUM> of ice maker <NUM> includes a plurality of mold cavities <NUM> defined in the mold body <NUM> for forming ice <NUM> therein. In the example illustrated by <FIG>, the mold body <NUM> includes a single row of four mold cavities <NUM>. In other embodiments, more or fewer mold cavities <NUM> may be included, such as in multiple rows. For example, as shown in <FIG>, the plurality of mold cavities <NUM> may include a first row <NUM> of mold cavities <NUM> extending generally along the transverse direction TI and a second row <NUM> of mold cavities <NUM> extending generally along the transverse direction TI and spaced apart from the first row <NUM> along the lateral direction LI. In various embodiments, the first and second rows <NUM> and <NUM> may each include four mold cavities <NUM>, as shown in <FIG>, or may include any suitable number of mold cavities <NUM>. For example, one or both of the first and second rows <NUM> and <NUM> may include three or fewer mold cavities <NUM>. In other embodiments, one or both of the first and second rows <NUM> and <NUM> may include more than four mold cavities <NUM>. The first and second rows <NUM> and <NUM> may include different numbers of mold cavities <NUM>, e.g., one of the first and second rows <NUM> and <NUM> may include three mold cavities <NUM> while the other of the first and second rows <NUM> and <NUM> may include four mold cavities <NUM>, as well as various other combinations of numbers of mold cavities <NUM>.

The mold cavities <NUM> may be configured to receive liquid water to form ice <NUM> in each mold cavity <NUM>. As will be understood, the shape of ice <NUM> formed in the mold cavities <NUM> will correspond to the shape of the mold cavity <NUM>. The mold cavities <NUM> may be generally cylindrical. Accordingly, generally cylindrical ice, sometimes referred to as "barrel ice," may be produced by the ice maker <NUM>, e.g., the ice <NUM> may be ice barrels <NUM>. Example embodiments of the generally cylindrical mold cavity <NUM> may include tapered sidewalls, e.g., forming an angle of up to ten degrees with a floor <NUM> of the mold cavity <NUM>, convex sidewalls, and/or concave sidewalls. In some embodiments, the generally cylindrical mold cavity <NUM> may have any suitable cross-sectional shape, e.g., hexagonal, instead of a round, e.g., circular or oval, cross-section.

As may be seen in <FIG>, each mold cavity <NUM> is enclosed between the floor <NUM> and the opening <NUM> by at least one sidewall <NUM>. For example, in the illustrated embodiments, the sidewall <NUM> is generally cylindrical. As noted above, in other embodiments, the mold cavities <NUM> may be, e.g., hexagonal, and thus may include more than one, e.g., six, sidewalls <NUM> enclosing each mold cavity <NUM> between the floor <NUM> and the opening <NUM>.

As may be seen in <FIG> and <FIG>, the ice maker <NUM> may include a heater <NUM> in thermal communication with the floor <NUM> of each mold cavity <NUM> of the plurality of mold cavities <NUM>. In some embodiments, a heat pipe <NUM> (<FIG>) may be provided to promote even distribution of thermal energy, e.g., heat, from the heater <NUM> to each of the mold cavities <NUM>. Each of the mold cavities <NUM> extends between a floor <NUM> and an opening <NUM> along a longitudinal axis A (<FIG>). The longitudinal axis A of each mold cavity <NUM> is oriented generally along the vertical direction VI of the ice maker <NUM>, and may in some embodiments also be generally aligned with the vertical direction V of the refrigerator appliance <NUM>.

Still referring to <FIG> and <FIG>, the opening <NUM> is exposed to a flow of chilled air, e.g., cool or cold air, where "cool" or "cold" refers to air having a sufficiently low temperature to freeze water in the mold cavities <NUM>, such as a temperature less than about thirty-two degrees Fahrenheit (<NUM>°F or <NUM>), thereby forming ice <NUM> in the mold cavities. For example, the chilled air may have a temperature of between about zero degrees Fahrenheit (<NUM>°F or -<NUM>) and about twenty-five degrees Fahrenheit (<NUM>°F or -<NUM>). For example, the chilled air flow may be directed to or towards the openings <NUM> by the fan <NUM> (<FIG>), as described above. The heater <NUM> is positioned proximate to the floor <NUM> of each mold cavity <NUM> such that the heating element(s) heat water at the floor <NUM> of each mold cavity <NUM>. As shown in <FIG>, each mold cavity may include a lower portion <NUM> and an upper portion <NUM>. For example, the lower portion <NUM> may comprise about half of the mold cavity <NUM>, from the floor <NUM> to a midpoint between the floor <NUM> and the opening <NUM>, and the upper portion <NUM> may comprise about half of the mold cavity <NUM>, from the midpoint to the opening <NUM>. The heater <NUM> may be configured to maintain water within the lower portion <NUM> of each mold cavity <NUM> in a liquid state. Thus, in operation, ice <NUM> may be formed within the mold cavities <NUM> from the top down, from the opening <NUM> due to contact with the cool or cold air, towards the floor <NUM>, where the water in the mold cavity <NUM> will remain liquid due to the heater <NUM>. For example, as shown in <FIG>, ice <NUM> may form in the upper portion <NUM> of the mold cavity <NUM>, while liquid water remains in the lower portion <NUM>. The remaining liquid, unfrozen water may also be referred to as ballast water.

Forming the ice <NUM> in one direction, e.g., from the top down as described above, results in formation of clear ice. In particular, as the ice is forming, e.g., when the water is slightly above the freezing point, such as about <NUM> or <NUM> degrees above freezing, the water in the mold cavities <NUM>, in particular the portion of the water which is exposed to the cold air, e.g., at the openings <NUM> of the mold cavities <NUM>, will start to expand as it solidifies and then float at or towards the top, e.g., the opening <NUM>, of each mold cavity <NUM>. During this process, any impurities, e.g., dissolved solids and/or suspended solids, which may be present in the water tend to be forced downwards. As a result, the ice <NUM> is more pure or cleaner and the ballast water is dirtier.

The ice maker <NUM> may include an ejector assembly for removing the ice barrels <NUM> from the mold body <NUM>, for example as shown in <FIG>, the ejector assembly may include a plurality of ejector pads <NUM>. The plurality of ejector pads <NUM> may correspond to the plurality of mold cavities <NUM>, e.g., the plurality of ejector pads <NUM> may include a number of ejector pads <NUM> corresponding to the number of mold cavities <NUM>. For example, in embodiments where the mold body <NUM> includes six mold cavities <NUM>, the ejector assembly may include six ejector pads <NUM>. Each ejector pad <NUM> is located within a corresponding mold cavity <NUM>.

The plurality of ejector pads <NUM> may be movable between a low position (e.g., as shown in <FIG>) proximate the floor <NUM> and a high position proximate the opening <NUM> (not shown). Accordingly, when ice <NUM> is formed within one or more of the mold cavities <NUM>, moving the corresponding ejector pads <NUM> of each of the respective mold cavities <NUM> from the low position to the high position may eject the ice <NUM> from the respective mold cavities <NUM>. In various embodiments, the motor <NUM> may be in operative communication with the ejector assembly, such that the motor <NUM> is operable to move the plurality of ejector pads <NUM> generally along the vertical direction VI between the low position and the high position.

When the ice <NUM> is harvested, e.g., ejected, from the mold cavities <NUM>, the liquid water, e.g., ballast water, in the lower portion <NUM> of each mold cavity <NUM>, e.g., proximate the floor <NUM>, is also ejected and must be managed, e.g., to avoid undesired ice formation on and around the mold body <NUM> other than in the mold cavities <NUM>. Accordingly, a drain conduit <NUM> is e.g., as shown in <FIG>. The drain conduit <NUM> is in fluid communication with the mold body <NUM> and may be configured to receive a flow of liquid water <NUM> from the mold body <NUM>, e.g., from the mold cavities <NUM> therein.

For example, as shown in <FIG> and <FIG>, the drain conduit <NUM> may be in fluid communication with the lower portions <NUM> of the mold cavities <NUM> and configured to receive the liquid water <NUM> from the lower portions <NUM> of the mold cavities <NUM>, e.g., during harvest of the ice <NUM>. In some embodiments, e.g., as illustrated in <FIG> and <FIG>, the mold body <NUM> may include a plurality of passages <NUM>. Each passage <NUM> of the plurality of passages <NUM> may extend between the lower portion <NUM> of a respective one of the mold cavities <NUM> and the drain conduit <NUM>.

More particularly, in the example embodiment illustrated in <FIG>, one of the plurality of passages <NUM> may extend between the lower portion <NUM> of a mold cavity <NUM> in the first row <NUM> and the drain conduit <NUM>, e.g., from the lower portion <NUM> of the mold cavity <NUM> in the first row <NUM> to the lower portion <NUM> of a neighboring mold cavity <NUM> in the second row <NUM>, and another of the plurality of passages <NUM> may extend between the lower portion <NUM> of the neighboring mold cavity <NUM> in the second row <NUM> and the drain conduit <NUM>, e.g., from the lower portion <NUM> of the neighboring mold cavity <NUM> in the second row <NUM> to the drain conduit <NUM>. In such embodiments, each of the passages <NUM> may extend generally along the lateral direction LI of the ice maker <NUM>. Some such embodiments may further include a valve <NUM> between the plurality of passages <NUM> and the drain conduit <NUM>, e.g., the plurality of passages <NUM> of the mold body <NUM> may be coupled to the drain conduit <NUM> via the valve <NUM>, as illustrated for example in <FIG>. In embodiments where the valve <NUM> is provided, the valve <NUM> may be actuated, e.g., by the motor <NUM>, when the ice <NUM> is harvested, thereby draining the ballast water <NUM> during harvest.

In some embodiments, such as the example embodiment illustrated in <FIG>, the plurality of passages <NUM> may extend generally along the vertical direction VI of the ice maker <NUM>. In such embodiments, the ballast water <NUM>, e.g., the water which remains in the liquid state in the lower portion <NUM> of each mold cavity <NUM> due to the thermal energy from the heater <NUM>, may flow out of each mold cavity <NUM> by gravity. In such embodiments, for example as illustrated in <FIG>, each passage <NUM> may extend directly from a corresponding mold cavity <NUM> to an external surface of the mold body <NUM>. During ice formation, the passages <NUM> may be obstructed by the ejector pads <NUM> in each mold cavity <NUM>, e.g., where the ejector pads <NUM> are in the low position during ice formation. When the ejector pads <NUM> are raised, e.g., moved to the high position, during harvest each ejector pad <NUM> will be spaced apart from the corresponding passage <NUM> of the plurality of passages <NUM>, such that the ballast water <NUM> may flow out of the respective mold cavity <NUM> during harvest.

In some embodiments, as illustrated in <FIG>, excess liquid water <NUM> may be added to each of the mold cavities <NUM> during the fill process, e.g., when the mold cavities <NUM> are filled with liquid water after a harvest. This excess water <NUM> may then flow out of the mold cavities <NUM>, as shown, and may thereby serve to dilute the ballast water <NUM>, e.g., by removing at least some of the impurities from the liquid water in each mold cavity <NUM> to promote formation of clear ice <NUM>. In such embodiments, the drain conduit <NUM> may be disposed adjacent to the mold body <NUM>, e.g., just below the mold body <NUM> along the vertical direction V and/or VI. Further, the mold body <NUM>, such as a top surface thereof, may be slanted towards the drain conduit <NUM> to promote the flow of the excess water <NUM> to or towards the drain conduit <NUM>. Also in such embodiments, the drain conduit <NUM> may include an enlarged inlet such as a funnel-shaped inlet to promote capture of the overflowing excess water <NUM> from the mold body <NUM>.

Turning now to <FIG>, in some embodiments, the drain conduit <NUM> may be further in fluid communication with a drain pan <NUM> of the refrigerator appliance <NUM>. For example, the drain pan <NUM> may be shallow, providing a large surface area for evaporation of water collected therein. In such embodiments, as shown in <FIG>, the drain conduit <NUM> may be configured to direct the received flow of liquid water <NUM> and/or <NUM> from the mold cavities <NUM> to the drain pan <NUM>. The drain pan <NUM> may also be configured to receive, e.g., condensation from various portions of the refrigerator appliance <NUM> and/or melt water from the ice storage bin <NUM>. For example, the ice storage bin <NUM> may be connected to a drain <NUM> providing fluid communication between the ice storage bin <NUM> and the drain pan <NUM> for melt water from the ice storage bin <NUM>.

According to the invention, as shown in <FIG>, the drain conduit <NUM> is further in fluid communication with a recirculation assembly <NUM>. The recirculation assembly <NUM> includes a recirculation pump <NUM> and a filter <NUM> downstream from the recirculation pump <NUM> and upstream of the mold cavities <NUM>. The recirculation pump <NUM> is configured to urge liquid water from the drain conduit <NUM> to the mold cavities <NUM> via the filter <NUM>. Accordingly, impurities which may be concentrated in the ballast water <NUM> and/or the overflow water <NUM> may be removed by the filter <NUM> before the water is returned to the mold cavities <NUM>, promoting formation of clear ice <NUM> within the mold cavities <NUM>. In some embodiments, the filter <NUM> may be an ion-exchange filter. In other embodiments, any suitable filter may be provided, such as a membrane filter or a carbon filter.

In some embodiments, as shown in <FIG>, the drain conduit <NUM> may be further in fluid communication with an auxiliary ice maker <NUM>. Regular cloudy ice <NUM> may be formed in the auxiliary ice maker <NUM>. In some instances, the auxiliary ice maker <NUM> may be useful for providing faster ice production as opposed to the clear ice barrels <NUM> formed in the ice maker <NUM>. For example, the auxiliary ice maker <NUM> may have a greater capacity, e.g., a higher number of mold cavities for forming ice, than the clear ice maker <NUM>. The cloudy ice <NUM> may be used, e.g., to fill a cooler or for first-aid purposes, preserving the clear ice barrels <NUM> for use, e.g., in beverages.

In some embodiments, as shown in <FIG>, the drain conduit <NUM> may be further in fluid communication with a sump <NUM>. The drain conduit <NUM> may be configured to direct the received flow of liquid water <NUM> and/or <NUM> from the mold cavities <NUM> to the sump <NUM>. Water stored in the sump <NUM> may be removed by evaporation or dispersed using an ultrasonic device. The sump <NUM> may also include a plumbed drain, e.g., connected to a household plumbing system, for removal of water from the sump <NUM> by pressure and/or gravity flow.

Turning now to <FIG>, embodiments of the present disclosure may also include a method of making clear ice in a refrigerator appliance, such as the exemplary method <NUM> illustrated in <FIG>. As illustrated in <FIG>, the method <NUM> may include a step <NUM> of filling a plurality of mold cavities in a mold body of an ice maker with liquid water. The method <NUM> may further include a step <NUM> of directing a flow of chilled air from the chilled chamber of the refrigerator towards openings of the plurality of mold cavities. As a result of the flow of chilled air, the liquid water in an upper portion of each of the plurality of mold cavities may freeze from the top down, such that clear ice barrels are formed in the plurality of mold cavities.

Claim 1:
A refrigerator appliance (<NUM>) comprising:
a cabinet (<NUM>) defining a chilled chamber;
an ice maker (<NUM>) in thermal communication with the chilled chamber, the ice maker (<NUM>) defining a vertical direction, (V), a lateral direction, (L), and a transverse direction, (T), the vertical, lateral, and transverse directions being mutually perpendicular, the ice maker (<NUM>) comprising:
a mold body, (<NUM>), a plurality of mold cavities (<NUM>) defined in the mold body, (<NUM>), each mold cavity (<NUM>) of the plurality of mold cavities (<NUM>) extending between a floor (<NUM>) and an opening (<NUM>) along a longitudinal axis, (A), each mold cavity (<NUM>) of the plurality of mold cavities (<NUM>) enclosed by at least one sidewall (<NUM>) between the floor (<NUM>) and the opening, (<NUM>), the longitudinal axis (A) of each mold cavity (<NUM>) oriented generally along the vertical direction; (V);
a heater (<NUM>) in thermal communication with the floor (<NUM>) of each mold cavity (<NUM>) of the plurality of mold cavities, (<NUM>), the heater (<NUM>) configured to maintain water within a lower portion (<NUM>) of each mold cavity (<NUM>) in a liquid state; and
a drain conduit (<NUM>) in fluid communication with the mold body (<NUM>) and configured to receive a flow of liquid water (<NUM>) from the mold cavities (<NUM>), characterized in that the drain conduit (<NUM>) is further in fluid communication with a recirculation assembly, (<NUM>), the recirculation assembly (<NUM>) comprising a recirculation pump (<NUM>) and a filter (<NUM>) downstream from the recirculation pump (<NUM>) and upstream of the mold cavities, (<NUM>), and wherein the recirculation pump (<NUM>) is configured to urge liquid water from the drain conduit (<NUM>) to the mold cavities (<NUM>) via the filter (<NUM>).