Patent Description:
In domestic and commercial applications, ice is often formed as solid cubes, such as crescent cubes or generally rectangular blocks. The shape of such cubes is often dictated by the container holder water during a freezing process. For instance, an ice maker can receive liquid water, and such liquid water can freeze within the ice maker to form ice cubes. In particular, certain ice makers include a freezing mold that defines a plurality of cavities. The plurality of cavities can be filled with liquid water, and such liquid water can freeze within the plurality of cavities to form solid ice cubes. Typical solid cubes or blocks may be relatively small in order to accommodate a large number of uses, such as temporary cold storage and rapid cooling of liquids in a wide range of sizes.

Although the typical solid cubes or blocks may be useful in a variety of circumstances, there are certain conditions in which distinct or unique ice shapes may be desirable. As an example, it has been found that relatively large ice cubes or spheres (e.g., larger than <NUM>,<NUM> (two inches) in diameter) will melt slower than typical ice sizes/shapes. Slow melting of ice may be especially desirable in certain liquors or cocktails. Moreover, such cubes or spheres may provide a unique or upscale impression for the user.

In recent years, ice making appliances have been developed for forming relatively large ice billets in a manner that avoids trapping impurities and gases within the billet. These appliances also use precise temperature control to avoid a dull or cloudy finish that may form on the exterior surfaces of an ice billet (e.g., during rapid freezing of the ice cube). In addition, in order to ensure that a shaped or final ice cube or sphere is substantially clear, many systems form solid ice billets that are substantially bigger (e.g., <NUM>% larger in mass or volume) than a desired final ice cube or sphere. Along with being generally inefficient, this may significantly increase the amount of time and energy required to melt or shape an initial ice billet into a final cube or sphere.

Conventional ice making assemblies for forming large billets of ice often experience issues keeping the ice mold cool enough to freeze through the thickness of the large ice billet, particularly toward the bottom of the ice billet or at regions farthest away from the evaporator. Accordingly, further improvements in the field of ice making would be desirable. In particular, an evaporator assembly that quickly and efficiently cools an ice mold of an ice making assembly would be particularly beneficial.

Examples of ice making assemblies are presented in <CIT>, <CIT>, <CIT>, <CIT> and <CIT>.

In one exemplary aspect of the present disclosure, an ice making assembly as presented in claim <NUM> is provided.

In another exemplary aspect of the present disclosure, a method of forming an ice making assembly as presented in claim <NUM> is provided.

As used herein, 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. The terms "includes" and "including" are intended to be inclusive in a manner similar to the term "comprising. " Similarly, the term "or" is generally intended to be inclusive (i.e., "A or B" is intended to mean "A or B or both").

Turning now to the figures, <FIG> provides a side plan view of an ice making appliance <NUM>, including an ice making assembly <NUM>. <FIG> provides a schematic view of ice making assembly <NUM>. <FIG> provides a simplified perspective view of ice making assembly <NUM>. Generally, ice making appliance <NUM> includes a cabinet <NUM> (e.g., insulated housing) and defines a mutually orthogonal vertical direction V, lateral direction, and transverse direction. The lateral direction and transverse direction may be generally understood to be horizontal directions H.

As shown, cabinet <NUM> defines one or more chilled chambers, such as a freezer chamber <NUM>. In certain embodiments, such as those illustrated by <FIG>, ice making appliance <NUM> is understood to be formed as, or as part of, a stand-alone freezer appliance. It is recognized, however, that additional or alternative embodiments may be provided within the context of other refrigeration appliances. For instance, the benefits of the present disclosure may apply to any type or style of a refrigerator appliance that includes a freezer chamber (e.g., a top mount refrigerator appliance, a bottom mount refrigerator appliance, a side-by-side style refrigerator appliance, etc.). Consequently, the description set forth herein is for illustrative purposes only and is not intended to be limiting in any aspect to any particular chamber configuration.

Ice making appliance <NUM> generally includes an ice making assembly <NUM> on or within freezer chamber <NUM>. In some embodiments, ice making appliance <NUM> includes a door <NUM> that is rotatably attached to cabinet <NUM> (e.g., at a top portion thereof). As would be understood, door <NUM> may selectively cover an opening defined by cabinet <NUM>. For instance, door <NUM> may rotate on cabinet <NUM> between an open position (not pictured) permitting access to freezer chamber <NUM> and a closed position (<FIG>) restricting access to freezer chamber <NUM>.

A user interface panel <NUM> is provided for controlling the mode of operation. For example, user interface panel <NUM> may include a plurality of user inputs (not labeled), such as a touchscreen or button interface, for selecting a desired mode of operation. Operation of ice making 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 ice making appliance <NUM> such as (e.g., selections regarding chamber temperature, ice making speed, 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 ice making appliance <NUM> or ice making assembly <NUM>.

Controller <NUM> may include a memory (e.g., non-transitive 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 ice making 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 ice making appliance <NUM>. In optional embodiments, controller <NUM> is located within the user interface panel <NUM>. In other embodiments, the controller <NUM> may be positioned at any suitable location within ice making appliance <NUM>, such as for example within cabinet <NUM>. Input/output ("I/O") signals may be routed between controller <NUM> and various operational components of ice making appliance <NUM>. For example, user interface panel <NUM> may be in communication with controller <NUM> via one or more signal lines or shared communication busses.

As illustrated, controller <NUM> may be in communication with the various components of ice making assembly <NUM> and may control operation of the various components. For example, various valves, switches, etc. may be actuatable based on commands from the controller <NUM>. As discussed, user interface panel <NUM> may additionally be in communication with the controller <NUM>. Thus, the various operations may occur based on user input or automatically through controller <NUM> instruction.

Generally, as shown in <FIG>, ice making appliance <NUM> includes a sealed refrigeration system <NUM> for executing a vapor compression cycle for cooling water within ice making appliance <NUM> (e.g., within freezer chamber <NUM>). Sealed refrigeration system <NUM> includes a compressor <NUM>, a condenser <NUM>, an expansion device <NUM>, and an evaporator <NUM> connected in fluid series and charged with a refrigerant. As will be understood by those skilled in the art, sealed refrigeration system <NUM> may include additional components (e.g., one or more directional flow valves or an additional evaporator, compressor, expansion device, or condenser). Moreover, at least one component (e.g., evaporator <NUM>) is provided in thermal communication (e.g., conductive thermal communication) with an ice mold or mold assembly <NUM> (<FIG>) to cool mold assembly <NUM>, such as during ice making operations. Optionally, evaporator <NUM> is mounted within freezer chamber <NUM>, as generally illustrated in <FIG>.

Within sealed refrigeration 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 chamber <NUM>. As such, cooled water and ice or air is produced and refrigerates ice making appliance <NUM> or freezer chamber <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>.

Optionally, as described in more detail below, one or more directional valves may be provided (e.g., between compressor <NUM> and condenser <NUM>) to selectively redirect refrigerant through a bypass line connecting the directional valve or valves to a point in the fluid circuit downstream from the expansion device <NUM> and upstream from the evaporator <NUM>. In other words, the one or more directional valves may permit refrigerant to selectively bypass the condenser <NUM> and expansion device <NUM>.

In additional or alternative embodiments, ice making appliance <NUM> further includes a valve <NUM> for regulating a flow of liquid water to ice making assembly <NUM>. For example, valve <NUM> may be selectively adjustable between an open configuration and a closed configuration. In the open configuration, valve <NUM> permits a flow of liquid water to ice making assembly <NUM> (e.g., to a water dispenser <NUM> or a water basin <NUM> of ice making assembly <NUM>). Conversely, in the closed configuration, valve <NUM> hinders the flow of liquid water to ice making assembly <NUM>.

In certain embodiments, ice making appliance <NUM> also includes a discrete chamber cooling system <NUM> (e.g., separate from sealed refrigeration system <NUM>) to generally draw heat from within freezer chamber <NUM>. For example, discrete chamber cooling system <NUM> may include a corresponding sealed refrigeration circuit (e.g., including a unique compressor, condenser, evaporator, and expansion device) or air handler (e.g., axial fan, centrifugal fan, etc.) configured to motivate a flow of chilled air within freezer chamber <NUM>.

Turning now to <FIG> provides a cross-sectional, schematic view of ice making assembly <NUM>. As shown, ice making assembly <NUM> includes a mold assembly <NUM> that defines a mold cavity <NUM> within which an ice billet <NUM> may be formed. Optionally, a plurality of mold cavities <NUM> may be defined by mold assembly <NUM> and spaced apart from each other (e.g., perpendicular to the vertical direction V). One or more portions of sealed refrigeration system <NUM> may be in thermal communication with mold assembly <NUM>. In particular, evaporator <NUM> may be placed on or in contact (e.g., conductive contact) with a portion of mold assembly <NUM>. During use, evaporator <NUM> may selectively draw heat from mold cavity <NUM>, as will be further described below. Moreover, a water dispenser <NUM> positioned below mold assembly <NUM> may selectively direct the flow of water into mold cavity <NUM>. Generally, water dispenser <NUM> includes a water pump <NUM> and at least one nozzle <NUM> directed (e.g., vertically) toward mold cavity <NUM>. In embodiments wherein multiple discrete mold cavities <NUM> are defined by mold assembly <NUM>, water dispenser <NUM> may include a plurality of nozzles <NUM> or fluid pumps vertically aligned with the plurality mold cavities <NUM>. For instance, each mold cavity <NUM> may be vertically aligned with a discrete nozzle <NUM>.

In some embodiments, a water basin <NUM> is positioned below the ice mold (e.g., directly beneath mold cavity <NUM> along the vertical direction V). Water basin <NUM> includes a solid nonpermeable body and may define a vertical opening <NUM> and interior volume <NUM> in fluid communication with mold cavity <NUM>. When assembled, fluids, such as excess water falling from mold cavity <NUM>, may pass into interior volume <NUM> of water basin <NUM> through vertical opening <NUM>. In certain embodiments, one or more portions of water dispenser <NUM> are positioned within water basin <NUM> (e.g., within interior volume <NUM>). As an example, water pump <NUM> may be mounted within water basin <NUM> in fluid communication with interior volume <NUM>. Thus, water pump <NUM> may selectively draw water from interior volume <NUM> (e.g., to be dispensed by spray nozzle <NUM>). Nozzle <NUM> may extend (e.g., vertically) from water pump <NUM> through interior volume <NUM>.

In optional embodiments, a guide ramp <NUM> is positioned between mold assembly <NUM> and water basin <NUM> along the vertical direction V. For example, guide ramp <NUM> may include a ramp surface that extends at a negative angle (e.g., relative to a horizontal direction) from a location beneath mold cavity <NUM> to another location spaced apart from water basin <NUM> (e.g., horizontally). In some such embodiments, guide ramp <NUM> extends to or terminates above an ice bin <NUM>. Additionally or alternatively, guide ramp <NUM> may define a perforated portion <NUM> that is, for example, vertically aligned between mold cavity <NUM> and nozzle <NUM> or between mold cavity <NUM> and interior volume <NUM>. One or more apertures are generally defined through guide ramp <NUM> at perforated portion <NUM>. Fluids, such as water, may thus generally pass through perforated portion <NUM> of guide ramp <NUM> (e.g., along the vertical direction between mold cavity <NUM> and interior volume <NUM>).

As shown, ice bin <NUM> generally defines a storage volume <NUM> and may be positioned below mold assembly <NUM> and mold cavity <NUM>. Ice billets <NUM> formed within mold cavity <NUM> may be expelled from mold assembly <NUM> and subsequently stored within storage volume <NUM> of ice bin <NUM> (e.g., within freezer chamber <NUM>). In some such embodiments, ice bin <NUM> is positioned within freezer chamber <NUM> and horizontally spaced apart from water basin <NUM>, water dispenser <NUM>, or mold assembly <NUM>. Guide ramp <NUM> may span the horizontal distance between mold assembly <NUM> and ice bin <NUM>. As ice billets <NUM> descend or fall from mold cavity <NUM>, the ice billets <NUM> may thus be motivated (e.g., by gravity) toward ice bin <NUM>.

Turning now generally to <FIG> and <FIG>, exemplary ice forming operations of ice making assembly <NUM> will be described. As shown, mold assembly <NUM> is formed from discrete conductive ice mold <NUM> and insulation jacket <NUM>. Generally, insulation jacket <NUM> extends downward from (e.g., directly from) conductive ice mold <NUM>. For instance, insulation jacket <NUM> may be fixed to conductive ice mold <NUM> through one or more suitable adhesives or attachment fasteners (e.g., bolts, latches, mated prongs-channels, etc.) positioned or formed between conductive ice mold <NUM> and insulation jacket <NUM>.

Together, conductive ice mold <NUM> and insulation jacket <NUM> may define mold cavity <NUM>. For instance, conductive ice mold <NUM> may define an upper portion 136A of mold cavity <NUM> while insulation jacket <NUM> defines a lower portion 136B of mold cavity <NUM>. Upper portion 136A of mold cavity <NUM> may extend between a nonpermeable top end <NUM> and an open bottom end <NUM>. Additionally or alternatively, upper portion 136A of mold cavity <NUM> may be curved (e.g., hemispherical) in open fluid communication with lower portion 136B of mold cavity <NUM>. Lower portion 136B of mold cavity <NUM> may be a vertically open passage that is aligned (e.g., in the vertical direction V) with upper portion 136A of mold cavity <NUM>. Thus, mold cavity <NUM> may extend along the vertical direction between a mold opening <NUM> at a bottom portion or bottom surface <NUM> of insulation jacket <NUM> to top end <NUM> within conductive ice mold <NUM>. In some such embodiments, mold cavity <NUM> defines a constant diameter or horizontal width from lower portion 136B to upper portion 136A. When assembled, fluids, such as water may pass to upper portion 136A of mold cavity <NUM> through lower portion 136B of mold cavity <NUM> (e.g., after flowing through the bottom opening defined by insulation jacket <NUM>).

Conductive ice mold <NUM> and insulation jacket <NUM> are formed, at least in part, from two different materials. Conductive ice mold <NUM> is generally formed from a thermally conductive material (e.g., metal, such as copper, aluminum, or stainless steel, including alloys thereof) while insulation jacket <NUM> is generally formed from a thermally insulating material (e.g., insulating polymer, such as a synthetic silicone configured for use within subfreezing temperatures without significant deterioration). According to alternative embodiments, insulation jacket <NUM> may be formed using polyethylene terephthalate (PET) plastic or any other suitable material. In some embodiments, conductive ice mold <NUM> is formed from material having a greater amount of water surface adhesion than the material from which insulation jacket <NUM> is formed. Water freezing within mold cavity <NUM> may be prevented from extending horizontally along bottom surface <NUM> of insulation jacket <NUM>.

Advantageously, an ice billet within mold cavity <NUM> may be prevented from mushrooming beyond the bounds of mold cavity <NUM>. Moreover, if multiple mold cavities <NUM> are defined within mold assembly <NUM>, ice making assembly <NUM> may advantageously prevent a connecting layer of ice from being formed along the bottom surface <NUM> of insulation jacket <NUM> between the separate mold cavities <NUM> (and ice billets therein). Further advantageously, the present embodiments may ensure an even heat distribution across an ice billet within mold cavity <NUM>. Cracking of the ice billet or formation of a concave dimple at the bottom of the ice billet may thus be prevented.

In some embodiments, the unique materials of conductive ice mold <NUM> and insulation jacket <NUM> each extend to the surfaces defining upper portion 136A and lower portion 136B of mold cavity <NUM>. In particular, a material having a relatively high water adhesion may define the bounds of upper portion 136A of mold cavity <NUM> while a material having a relatively low water adhesion defines the bounds of lower portion 136B of mold cavity <NUM>. For instance, the surface of insulation jacket <NUM> defining the bounds of lower portion 136B of mold cavity <NUM> may be formed from an insulating polymer (e.g., silicone). The surface of conductive mold cavity <NUM> defining the bounds of upper portion 136A of mold cavity <NUM> may be formed from a thermally conductive metal (e.g., aluminum or copper). In some such embodiments, the thermally conductive metal of conductive ice mold <NUM> may extend along (e.g., the entirety of) of upper portion 136A.

Although an exemplary mold assembly <NUM> is described above, it should be appreciated that variations and modifications may be made to mold assembly <NUM> while remaining within the scope of the present subject matter. For example, the size, number, position, and geometry of mold cavities <NUM> may vary. In addition, according to alternative embodiments, an insulation film may extend along and define the bounds of upper portion 136A of mold cavity <NUM>, e.g., may extend along an inner surface of conductive ice mold <NUM> at upper portion 136A of mold cavity <NUM>. Indeed, aspects of the present subject matter may be modified and implemented in a different ice making apparatus or process while remaining within the scope of the present subject matter.

In some embodiments, one or more sensors are mounted on or within ice mold <NUM>. As an example, a temperature sensor <NUM> may be mounted adjacent to ice mold <NUM>. Temperature sensor <NUM> may be electrically coupled to controller <NUM> and configured to detect the temperature within ice mold <NUM>. Temperature sensor <NUM> may be formed as any suitable temperature detecting device, such as a thermocouple, thermistor, etc. Although temperature sensor <NUM> is illustrated as being mounted to ice mold <NUM>, it should be appreciated that according to alternative embodiments, temperature sensor may be positioned at any other suitable location for providing data indicative of the temperature of the ice mold <NUM>. For example, temperature sensor <NUM> may alternatively be mounted to a coil of evaporator <NUM> or at any other suitable location within ice making appliance <NUM>.

As shown, controller <NUM> may be in communication (e.g., electrical communication) with one or more portions of ice making assembly <NUM>. In some embodiments, controller <NUM> is in communication with one or more fluid pumps (e.g., water pump <NUM>), compressor <NUM>, flow regulating valves, etc. Controller <NUM> may be configured to initiate discrete ice making operations and ice release operations. For instance, controller <NUM> may alternate the fluid source spray to mold cavity <NUM> and a release or ice harvest process, which will be described in more detail below.

During ice making operations, controller <NUM> may initiate or direct water dispenser <NUM> to motivate an ice-building spray (e.g., as indicated at arrows <NUM>) through nozzle <NUM> and into mold cavity <NUM> (e.g., through mold opening <NUM>). Controller <NUM> may further direct sealed refrigeration system <NUM> (e.g., at compressor <NUM>) (<FIG>) to motivate refrigerant through evaporator <NUM> and draw heat from within mold cavity <NUM>. As the water from the ice-building spray <NUM> strikes mold assembly <NUM> within mold cavity <NUM>, a portion of the water may freeze in progressive layers from top end <NUM> to bottom end <NUM>. Excess water (e.g., water within mold cavity <NUM> that does not freeze upon contact with mold assembly <NUM> or the frozen volume herein) and impurities within the ice-building spray <NUM> may fall from mold cavity <NUM> and, for example, to water basin <NUM>.

Once ice billets <NUM> are formed within mold cavity <NUM>, an ice release or harvest process may be performed in accordance with embodiments of the present subject matter. Specifically, referring again to <FIG>, sealed system <NUM> may further include a bypass conduit <NUM> that is fluidly coupled to refrigeration loop or sealed system <NUM> for routing a portion of the flow of refrigerant around condenser <NUM>. In this manner, by selectively regulating the amount of relatively hot refrigerant flow that exits compressor <NUM> and bypasses condenser <NUM>, the temperature of the flow of refrigerant passing into evaporator <NUM> may be precisely regulated.

Specifically, according to the illustrated embodiment, bypass conduit <NUM> extends from a first junction <NUM> to a second junction <NUM> within sealed system <NUM>. First junction <NUM> is located between compressor <NUM> and condenser <NUM>, e.g., downstream of compressor <NUM> and upstream of condenser <NUM>. By contrast, second junction <NUM> is located between condenser <NUM> and evaporator <NUM>, e.g., downstream of condenser <NUM> and upstream of evaporator <NUM>. Moreover, according to the illustrated embodiment, second junction <NUM> is also located downstream of expansion device <NUM>, although second junction <NUM> could alternatively be positioned upstream of expansion device <NUM>. When plumbed in this manner, bypass conduit <NUM> provides a pathway through which a portion of the flow of refrigerant may pass directly from compressor <NUM> to a location immediately upstream of evaporator <NUM> to increase the temperature of evaporator <NUM>.

Notably, if substantially all of the flow of refrigerant were diverted from compressor <NUM> through bypass conduit <NUM> when ice mold <NUM> is still very cold (e.g., below -<NUM>,<NUM> or -<NUM>,<NUM> (<NUM>°F or <NUM>°F)), the thermal shock experienced by ice billets <NUM> due to the sudden increase in evaporator temperature might cause ice billets <NUM> to crack. Therefore, controller <NUM> may implement methods for slowly regulating or precisely controlling the evaporator temperature to achieve the desired mold temperature profile and harvest release time to prevent the ice billets <NUM> from cracking.

In this regard, for example, bypass conduit <NUM> may be fluidly coupled to sealed system <NUM> using a flow regulating device <NUM>. Specifically, flow regulating device <NUM> may be used to couple bypass conduit <NUM> to sealed system <NUM> at first junction <NUM>. In general, flow regulating device <NUM> may be any device suitable for regulating a flow rate of refrigerant through bypass conduit <NUM>. For example, according to an exemplary embodiment of the present subject matter, flow regulating device <NUM> is an electronic expansion device which may selectively divert a portion of the flow of refrigerant exiting compressor <NUM> into bypass conduit <NUM>. According to still another embodiment, flow regulating device <NUM> may be a servomotor-controlled valve for regulating the flow of refrigerant through bypass conduit <NUM>. According to still other embodiments, flow regulating device <NUM> may be a three-way valve mounted at first junction <NUM> or a solenoid-controlled valve operably coupled along bypass conduit <NUM>.

According to exemplary embodiments of the present subject matter, controller <NUM> may initiate an ice release or harvest process to discharge ice billets <NUM> from mold cavities <NUM>. Specifically, for example, controller <NUM> may first halt or prevent the ice-building spray <NUM> by de-energizing water pump <NUM>. Next, controller <NUM> may regulate the operation of sealed system <NUM> to slowly increase a temperature of evaporator <NUM> and ice mold <NUM>. Specifically, by increasing the temperature of evaporator <NUM>, the mold temperature of ice mold <NUM> is also increased, thereby facilitating partial melting or release of ice billets <NUM> from mold cavities.

According to exemplary embodiments, controller <NUM> may be operably coupled to flow regulating device <NUM> for regulating a flow rate of the flow of refrigerant through bypass conduit <NUM>. Specifically, according to an exemplary embodiment, controller <NUM> may be configured for obtaining a mold temperature of the mold body using temperature sensor <NUM>. Although the term "mold temperature" is used herein, it should be appreciated that temperature sensor <NUM> may measure any suitable temperature within the ice making appliance <NUM> that is indicative of mold temperature and may be used to facilitate improved harvest of ice billets <NUM>.

Controller <NUM> may further regulate the flow regulating device <NUM> to control the flow of refrigerant based in part on the measured mold temperature. For example, according to an exemplary embodiment, flow regulating device <NUM> may be regulated such that a rate of change of the mold temperature does not exceed a predetermined threshold rate. For example, this predetermined threshold rate may be any suitable rate of temperature change beyond which thermal cracking of ice billets <NUM> may occur. For example, according to an exemplary embodiment, the predetermined threshold rate may be approximately <NUM> (<NUM>°F) per minute, about <NUM>,<NUM> (<NUM>°F) per minute, about <NUM> (<NUM>°F) per minute, or higher. According to exemplary embodiments, the predetermined threshold rate may be less than <NUM> (<NUM>°F) per minute, less than <NUM> (<NUM>°F) per minute, less than <NUM> (<NUM>°F) per minute, or lower. In this manner, flow regulating device <NUM> may regulate the rate of temperature change of ice billets <NUM>, thereby preventing thermal cracking.

In general, the sealed system <NUM> and methods of operation described herein are intended to regulate a temperature change of ice billets <NUM> to prevent thermal cracking. However, although specific control algorithms and system configurations are described, it should be appreciated that according to alternative embodiments variations and modifications may be made to such systems and methods while remaining within the scope of the present subject matter. For example, the exact plumbing of bypass conduit <NUM> may vary, the type or position of flow regulating device <NUM> may change, and different control methods may be used while remaining within scope of the present subject matter. In addition, depending on the size and shape of ice billets <NUM>, the predetermined threshold rate and predetermined temperature threshold may be adjusted to prevent that particular set of ice billets <NUM> from cracking, or to otherwise facilitate an improved harvest procedure.

Referring now specifically to <FIG>, an exemplary ice mold <NUM> and evaporator assembly <NUM> that may be used with ice making appliance <NUM> will be described according to exemplary embodiments of the present subject matter. Specifically, for example, ice mold <NUM> may be used as mold assembly <NUM> and evaporator assembly <NUM> may be used as evaporator <NUM> of sealed cooling system <NUM>. Although ice mold <NUM> and evaporator assembly <NUM> are described herein with respect to ice making appliance <NUM>, it should be appreciated that ice mold <NUM> and evaporator assembly <NUM> may be used in any other suitable ice making application or appliance.

As shown, ice mold <NUM> generally includes a top wall <NUM> and a plurality of sidewalls <NUM> that are cantilevered from top wall <NUM> and extend downward from top wall <NUM>. More specifically, according to the illustrated embodiment, ice mold <NUM> includes eight sidewalls <NUM> that include an angled portion <NUM> that extends away from top wall <NUM> and a vertical portion <NUM> that extends down from angled portion <NUM> substantially along the vertical direction. In this manner, the top wall <NUM> and the plurality of sidewalls <NUM> form a mold cavity <NUM> having an octagonal cross-section when viewed in a horizontal plane. In addition, each of the plurality of sidewalls <NUM> may be separated by a gap <NUM> that extends substantially along the vertical direction. In this manner, the plurality of sidewalls <NUM> may move relative to each other and act as spring fingers to permit some flexing of ice mold <NUM> during ice formation. Notably, this flexibility of ice mold <NUM> facilitates improved ice formation and reduces the likelihood of cracking.

In general, ice mold <NUM> may be formed from any suitable material and in any suitable manner that provides sufficient thermal conductivity to transfer heat to evaporator assembly <NUM> to facilitate the ice making process. According to an exemplary embodiment, ice mold <NUM> is formed from a single sheet of copper. In this regard, for example, a flat sheet of copper having a constant thickness may be machined to define top wall <NUM> and sidewalls <NUM>. Sidewalls <NUM> may be subsequently bent to form the desired shape of mold cavity <NUM>, e.g., such as the octagonal or gem shape described above. In this manner, top wall <NUM> and sidewalls <NUM> may be formed to have an identical thickness without requiring complex and costly machining processes.

According exemplary embodiments of the present subject matter, evaporator assembly <NUM> is mounted in direct contact with the top wall <NUM> of ice mold <NUM>. In addition, evaporator assembly <NUM> may not be in direct contact with sidewalls <NUM>. This may be desirable, for example, to prevent restricting the movement of sidewalls <NUM>, e.g., to reduce to the likelihood of ice cracking. Notably, when evaporator assembly <NUM> is mounted only on top wall <NUM>, the conductive path to each of the plurality of sidewalls <NUM> is through the joint or connection where sidewalls <NUM> meet top wall <NUM>. Thus, it may be desirable to make a sidewall width <NUM> as large as possible to provide improved thermal conductivity. For example, the sidewall width <NUM> may be between about <NUM> and about <NUM>(about <NUM> and <NUM> inches), between about <NUM> and <NUM>,<NUM> (about <NUM> and <NUM> inches), or about <NUM> (about <NUM> inches). Such a sidewall width <NUM> facilitates the conduction of thermal energy to the bottom ends of each of the plurality of sidewalls <NUM>.

In addition, to improve the thermal contact between evaporator assembly <NUM> and ice mold <NUM>, it may be desirable to make top wall relatively large. Therefore, according to exemplary embodiments, top wall <NUM> may define a top width <NUM> and mold cavity <NUM> may define a max width <NUM>. According to exemplary embodiments, top width <NUM> is greater than about <NUM>% of max width <NUM>. According to still other embodiments, top width <NUM> may be greater than about <NUM>%, greater than about <NUM>%, greater than about <NUM>%, or greater, of max width <NUM>. In addition, or alternatively, top width <NUM> may be less than <NUM>%, less than <NUM>%, less than <NUM>%, less than <NUM>%, or less, of max width <NUM>. It should be appreciated that other suitable sizes, geometries, and configurations of ice mold <NUM> are possible and within the scope of the present subject matter. In addition, although only two ice molds <NUM> are illustrated in <FIG>, it should be appreciated that alternative embodiments may include any other suitable number and configuration of ice molds <NUM>.

Referring still to <FIG>, evaporator assembly <NUM> includes a primary evaporator tube <NUM> and a thermal enhancement structure <NUM> which is positioned within primary evaporator tube <NUM>. According to an example not forming part of this invention, primary evaporator tube may be a copper pipe having a circular cross section. The diameter of primary evaporator tube <NUM> may be between about <NUM> and <NUM> (about <NUM> and <NUM> inches), between about <NUM> and <NUM>(about <NUM> and <NUM> inches), between about <NUM> and <NUM>(about <NUM> and <NUM> inches), between about <NUM> and <NUM> (about <NUM> and <NUM> inches), or about <NUM> (about <NUM> inches). However, it should be appreciated that primary evaporator tube <NUM> may be any other suitable size, shape, length, and material.

As used herein, "thermal enhancement structure" is generally intended to refer to any suitable material, structure, or features within interior of primary evaporator tube <NUM> which are intended to increase the refrigerant side surface area within primary evaporator tube <NUM>. According to this invention, as best shown in <FIG>, thermal enhancement structure <NUM> is a plurality of internal tubes <NUM> that are stacked within primary evaporator tube <NUM>. In general, these internal tubes <NUM> may be copper pipes that have a smaller diameter than primary evaporator tube <NUM>. Internal tubes <NUM> may be stacked in primary evaporator tube <NUM> and extend approximately the same length as primary evaporator tube <NUM>.

According to an exemplary embodiment, the thermal enhancement structure <NUM> includes greater than <NUM> tubes, greater than <NUM> tubes, greater than <NUM> tubes, greater than <NUM> tubes, or more. In addition, or alternatively, thermal enhancement structure <NUM> may include fewer than <NUM> tubes, fewer than <NUM> tubes, fewer than <NUM> tubes, or fewer. The diameter of each internal tube <NUM> may be between about <NUM> and <NUM> (about <NUM> and <NUM> inches), between about <NUM> and <NUM> (about <NUM> and <NUM> inches), between about <NUM> and <NUM> (about <NUM> and <NUM> inches), or about <NUM> (about <NUM> inches). In addition, it should be appreciated that internal tubes <NUM> may have different sizes, lengths, or cross sectional shapes, e.g., in order to efficiently and completely fill primary evaporator tube <NUM>.

Alternatively, as shown in <FIG>, thermal enhancement structure <NUM> according to this invention includes a copper foam or mesh structure <NUM>. Alternatively, thermal enhancement structure <NUM> may be a porous thermally conductive material, a honeycomb structure, a lattice structure, or any other suitable thermally conductive material that extends from the internal walls of primary evaporator tube <NUM> through the center of primary evaporator tube <NUM> to increase the refrigerant side surface area. It should be appreciated that any other suitable thermal enhancement structure <NUM> may be used.

As shown generally in <FIG>, after thermal enhancement structure <NUM> is positioned within primary evaporator tube <NUM>, primary evaporator tube <NUM> is pressed or otherwise formed into a flattened or noncircular cross sectional shape. In this manner, primary evaporator tube <NUM> may be placed in direct contact with the top wall <NUM> of ice mold <NUM> and may have improved thermal contact with the top wall <NUM>. In addition, the larger contact surface area between the top wall <NUM> and primary evaporator tube <NUM> facilitates a simplified brazing or soldering process to join primary evaporator tube <NUM> with top wall <NUM>. In addition, pressing primary evaporator tube <NUM> into a noncircular cross section improves the thermal contact between internal tubes <NUM>, e.g., to increase the refrigerant side surface area of evaporator assembly <NUM>. Once formed, according to an exemplary embodiment, evaporator assembly <NUM> may be used with sealed cooling system <NUM>. In this manner, for example, compressor <NUM> may urge a flow of refrigerant through condenser <NUM>, expansion device <NUM>, and evaporator assembly <NUM>, as described above.

Now that the construction of ice making appliance <NUM> and evaporator assembly <NUM> have been described according to exemplary embodiments, an exemplary method <NUM> of forming an evaporator assembly will be described. Although the discussion below refers to the exemplary method <NUM> of forming evaporator assembly <NUM>, one skilled in the art will appreciate that the exemplary method <NUM> is applicable to the operation of a variety of other evaporator configurations and methods of formation.

Referring now to <FIG>, method <NUM> includes, at step <NUM>, positioning a thermal enhancement structure inside a primary evaporator tube. In this regard, as explained above, thermal enhancement structure <NUM> may be copper internal tubes <NUM> or copper foam <NUM>. For example, <NUM> internal tubes having an outer diameter of <NUM> (<NUM> inches) may be positioned within primary evaporator tube <NUM>, which may be a copper tube having a diameter of <NUM> (<NUM> inches).

After the thermal enhancement structure is in place, step <NUM> includes pressing the primary evaporator tube into a non-circular shape to increase the thermal contact between the thermal enhancement structure and the primary evaporator tube. In this regard, for example, the primary evaporator tube <NUM> may be pressed or compressed to deform the primary evaporator tube <NUM> and create improved thermal contact between each of the internal tubes <NUM> and the primary evaporator tube <NUM>, as shown for example by dotted lines in <FIG>. The primary evaporator tube <NUM> may then be installed into a sealed refrigeration system, such as sealed cooling system <NUM> as evaporator <NUM>.

Step <NUM> includes attaching the primary evaporator tube onto an ice mold that defines a mold cavity. In this regard, for example, deformed primary evaporator tube <NUM> may be soldered, brazed, or otherwise attached to top wall <NUM> of ice mold <NUM>. In this manner, when sealed cooling system <NUM> is circulating refrigerant, primary evaporator tube <NUM> absorbs thermal energy from the ice mold <NUM> and transfers it to the refrigerant. The thermal enhancement structure <NUM> enables more efficient transfer of thermal energy from the ice mold <NUM> to the refrigerant.

<FIG> depicts steps performed in a particular order for purposes of illustration and discussion. Those of ordinary skill in the art, using the disclosures provided herein, will understand that the steps of any of the methods discussed herein can be adapted, rearranged, expanded, omitted, or modified in various ways without deviating from the scope of the present disclosure. Moreover, although aspects of method <NUM> are explained using ice making appliance <NUM> and evaporator assembly <NUM> as an example, it should be appreciated that these methods may be applied to the operation of any evaporator assembly or an ice making appliance having any other suitable configuration.

Claim 1:
An ice making assembly comprising:
an ice mold (<NUM>) defining a mold cavity;
a refrigeration loop comprising a condenser (<NUM>) and an expansion device (<NUM>) in serial flow communication with each other and with a evaporator assembly (<NUM>); and
a compressor (<NUM>) operably coupled to the refrigeration loop and being configured for circulating a flow of refrigerant through the refrigerant loop ;
a bypass conduit (<NUM>) that is fluidly coupled to the refrigeration loop for routing a portion of the flow of refrigerant around the condenser (<NUM>) ; the evaporator assembly (<NUM>) in thermal communication with the ice mold, the evaporator assembly (<NUM>) comprising:
a primary evaporator tube (<NUM>) formed into a non-circular cross section and placed in direct contact with the ice mold (<NUM>); and
a thermal enhancement structure (<NUM>) positioned within the primary evaporator tube (<NUM>), the thermal enhancement structure (<NUM>) is intended to increase the refrigerant side surface area within the primary evaporator tube (<NUM>) ;
characterized in that the thermal enhancement structure (<NUM>) comprises copper foam or a plurality of internal tubes (<NUM>), in particular greater than <NUM> tubes, in particular <NUM> tubes.