Caloric Heat Pump Ice Making Appliance

An appliance includes an ice maker and a caloric heat pump system for cooling the ice maker. The caloric heat pump system includes a pump for circulating a heat transfer fluid between first and second heat exchangers and caloric material stages in order to cool the ice maker with the first heat exchanger. A related ice making appliance is also provided.

FIELD OF THE INVENTION

The present subject matter relates generally to ice making appliances, such as stand-alone ice making appliances.

BACKGROUND OF THE INVENTION

Ice makers generally produce ice for the use of consumers, such as in drinks being consumed, for cooling foods or drinks to be consumed and/or for other various purposes. Certain refrigerator appliances include ice makers for producing ice. The ice maker can be positioned within the appliances' freezer chamber and direct ice into an ice bucket where it can be stored within the freezer chamber. Such refrigerator appliances can also include a dispensing system for assisting a user with accessing ice produced by the refrigerator appliances' ice maker. However, the incorporation of ice makers into refrigerator appliance can have drawbacks, such as limits on the amount of ice that can be produced and the reliance on the refrigeration system of the refrigerator appliance to form the ice. Recently, stand-alone ice makers have been developed. These ice makers are separate from refrigerator appliances and provide independent ice supplies. However, typical stand-alone ice makers are expensive, to the point of being cost-prohibitive to the typical consumer.

Refrigerators and stand-alone ice makers frequently utilize heat pumps to cool liquid water and form ice. Conventional sealed system technology typically utilizes a heat pump that relies on compression and expansion of a fluid refrigerant to receive and reject heat in a cyclic manner so as to effect a desired temperature change or i.e. transfer heat energy from one location to another. This cycle can be used to provide e.g., for the receiving of heat from the environment and the rejecting of such heat elsewhere. A variety of different fluid refrigerants have been developed that can be used with the heat pump in such systems.

While improvements have been made to such heat pump systems that rely on the compression of fluid refrigerant, at best such can still only operate at about forty-five percent or less of the maximum theoretical Carnot cycle efficiency. Also, some fluid refrigerants have been discontinued due to environmental concerns. The range of ambient temperatures over which certain refrigerant-based systems can operate may be impractical for certain locations. Other challenges with heat pumps that use a fluid refrigerant exist as well.

Accordingly, ice makers with features for efficiently cooling water would be useful. In particular, a stand-alone ice maker with features for efficiently cooling water without requiring compression of fluid refrigerant would be useful.

BRIEF DESCRIPTION OF THE INVENTION

The present subject matter provides an appliance. The appliance includes an ice maker and a caloric heat pump system for cooling the ice maker. The caloric heat pump system includes a pump for circulating a heat transfer fluid between first and second heat exchangers and caloric material stages in order to cool the ice maker with the first heat exchanger. A related ice making appliance is also provided. Additional 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.

In a first exemplary embodiment, an ice making appliance is provided. The ice making appliance includes a casing. An auger is disposed within the casing. A motor is coupled to the auger. The motor is operable to rotate the auger within the casing. A first heat exchanger is coupled to the casing for receiving heat from the casing. The ice making appliance also includes a second heat exchanger. A caloric heat pump system is configured for cooling the casing with the first heat exchanger. The caloric heat pump system includes a plurality of caloric material stages. A field generator is positioned proximate the caloric material stages. The field generator is positioned such that the caloric material stages are moved in and out of a field of the field generator during operation of the caloric heat pump system. The caloric heat pump system also includes a pump for circulating a heat transfer fluid between the first and second heat exchangers and the caloric material stages.

In a second exemplary embodiment, an appliance is provided. The appliance includes an ice maker. A first heat exchanger is coupled to the ice maker for receiving heat. The appliance also includes a second heat exchanger. A caloric heat pump system is configured for cooling the ice maker with the first heat exchanger. The caloric heat pump system includes a plurality of caloric material stages. A field generator is positioned proximate the caloric material stages. The field generator is positioned such that the caloric material stages are moved in and out of a field of the field generator during operation of the caloric heat pump system. The caloric heat pump system also includes a pump for circulating a heat transfer fluid between the first and second heat exchangers and the caloric material stages.

DETAILED DESCRIPTION

The present subject matter is directed to an ice maker coupled with a caloric heat pump system for heating or cooling water within the ice maker. While described in greater detail below in the context of a magneto-caloric heat pump system, one of skill in the art will recognize that other suitable caloric materials may be used in a similar manner to heat or cool water within the ice maker, i.e., apply a field, move heat, remove the field, move heat. For example, electro-caloric material heats up and cools down within increasing and decreasing electric fields. As another example, elasto-caloric material heats up and cools down when exposed to increasing and decreasing mechanical strain. As yet another example, baro-caloric material heats up and cools down when exposed to increasing and decreasing pressure. Such materials another other similar caloric materials may be used in place of or in addition to the magneto-caloric material described below to heat or cool water within the ice maker. Thus, caloric material is used broadly herein to encompass materials that undergo heating or cooling when exposed to a changing field from a field generator, where the field generator may be an electric field generator, an actuator for applying mechanical stress or pressure, etc.

Referring now toFIG. 1, one embodiment of an ice making appliance10in accordance with an exemplary embodiment of the present subject matter is illustrated. InFIG. 1, ice making appliance10is configured as a stand-alone ice making appliance. Thus, as discussed in greater detail below, ice making appliance10need not be plumbed to a pressurized water supply, such as a well or municipal water supply, to operate. However, it should be understood that the present subject matter is not limited to any particular type or style of ice maker or ice making appliance. For example, the present subject matter may be used in or with ice making appliances that are plumbed into pressurized water supplies to receive liquid water during operation. As another example, the present subject matter may be used to assist with cooling the ice maker described in U.S. Pat. No. 8,171,744 of Watson et al. or the ice maker described in U.S. Pat. No. 8,459,047 of Hall et al., both of which are incorporated by reference herein in their entirety. Thus, the present subject matter may also be used to cool crescent-cube style ice makers, dip tube or finger-style ice makers, auger-style ice makers or any other suitable style of ice maker in order to form ice from liquid water. Also, the present subject matter may be used within refrigerator appliances in order to cool water and form ice within ice makers of the refrigerator appliances. Accordingly, it should be understood that the present subject matter is not limited to the exemplary ice making appliance10illustrated inFIG. 1.

As shown, ice making appliance10includes an outer housing12which generally at least partially houses various other components of ice making appliance10therein. A container14is also illustrated. Container14defines a first storage volume16for receipt and storage of ice18. A user of ice making appliance10may access ice18within container14for consumption or other uses. Container14may include one or more sidewalls20and a base wall22(seeFIG. 2), which may together define first storage volume16. In exemplary embodiments, at least one sidewall20may be formed from a clear, see-through (i.e. transparent or translucent) material, such as a clear glass or plastic, such that a user can see into first storage volume16and thus view ice18therein. Further, in exemplary embodiments, container14may be removable, such as from outer housing12, by a user. This facilitates easy access by the user to ice within container14and further, for example, may provide access to a water tank24(seeFIG. 2) of ice making appliance10.

As discussed above, ice making appliance10may be a stand-alone ice making appliance, and thus are not connected to a refrigerator or other appliance. Additionally, in exemplary embodiments, ice making appliance10is not connected to plumbing or another water source that is external to ice making appliance10, such as a refrigerator water source. Rather, in exemplary embodiments, water is initially supplied to ice making appliance10manually by a user, such as by pouring water into water tank24. The stand-alone features may reduce costs associated with ice making appliance10and allows the consumer to position ice making appliance10at any suitable desired location, with the only requirement in some embodiments being access to an electrical source. Removable container14allows easy access to ice and allows container14to be moved to a different position from the remainder of ice making appliance10for ice usage purposes. Additionally, in exemplary embodiments, ice making appliance10may be configured to make nugget ice (as discussed herein) which is becoming increasingly popular with consumers.

Referring toFIGS. 2 and 3, various other components of ice making appliances10are illustrated. For example, as mentioned, ice making appliance10includes a water tank24. Water tank24defines a second storage volume26for receipt and holding of liquid water. Water tank24may include one or more sidewalls28and a base wall30which may together define second storage volume26. In exemplary embodiments, water tank24may be disposed below container14along a vertical direction V defined for ice making appliance10, as shown.

As discussed, in exemplary embodiments, liquid water is provided to water tank24for use in forming ice. Accordingly, ice making appliance10may further include a pump32. Pump32may be in fluid communication with second storage volume26. For example, liquid water may be flowable from second storage volume26through an opening31defined in water tank24, such as in a sidewall28thereof, and may flow through a conduit to and through pump32. Pump32may, when activated, actively flow liquid water from second storage volume26therethrough and from pump32.

Liquid water actively flowed from pump32may be flowed (for example through a suitable conduit) to a reservoir34. For example, reservoir34may define a third storage volume36, which may be defined by one or more sidewalls and a base wall, in the same or similar manner to water tank24. Third storage volume36may, for example, be in fluid communication with pump32and may thus receive liquid water that is actively flowed from water tank24, such as through pump32. Reservoir34and third storage volume36thereof may receive and contain liquid water to be provided to an ice maker50for the production of ice. Accordingly, third storage volume36may be in fluid communication with ice maker50. For example, liquid water may be flowed, such as through suitable conduits, from third storage volume36to ice maker50.

Ice maker50generally receives liquid water, such as from reservoir34, and freezes the water to form ice18. While any suitable style of ice maker is within the scope and spirit of the present disclosure, in exemplary embodiments, ice maker50is a nugget ice maker, and in particular is an auger-style ice maker. As shown, ice maker50includes a casing52into which liquid water from third storage volume36is flowed. Casing52is thus in fluid communication with third storage volume36. For example, casing52may include one or more sidewalls54which may define an interior volume56, and an opening (not shown) may be defined in a sidewall54. Water may be flowed from third storage volume36through the opening in sidewall54(such as via a suitable conduit) into interior volume56.

An auger60is disposed at least partially within casing52, e.g., such that auger60is rotatable within casing52. In particular, a motor61is coupled to auger60. For example, auger60may be mounted or fixed to a shaft of motor61. Motor61is operable to rotate auger60within casing52. Thus, when motor61is on, auger60rotates within casing52, and auger60may be stationary within casing52when motor61is off. Liquid water within casing52may at least partially freeze due to heat exchange, such as with a heat pump system100as discussed herein. The at least partially frozen water may be lifted by auger60within casing52. In particular, auger60may scrape the at least partially frozen water from an inner surface of casing52and lift the scraped at least partially frozen water upwardly within casing52. Further, in exemplary embodiments, the at least partially frozen water may be directed by auger60to and through an extruder62. Extruder62may extrude the at least partially frozen water to form ice, such as nuggets of ice18.

Formed ice18may be provided by ice maker50to container14, and may be received in first storage volume16thereof. For example, ice18formed by auger60and/or extruder62may be provide to container14. In exemplary embodiments, ice making appliance10may include a chute70for directing ice18produced by ice maker50towards first storage volume16. For example, as shown, chute70is generally positioned above container14along the vertical direction V. Thus, ice can slide off of chute70and drop into storage volume16of container14. Chute70may, as shown, extend between ice maker50and container14, and may include a body72which defines a passage74therethrough. Ice18may be directed from ice maker50(such as from auger60and/or extruder62) through passage74to container14. In some embodiments, for example, a sweep64, which may for example be connected to and rotate with auger60, may contact the ice emerging through extruder62from auger60and direct the ice through passage74to container14.

As discussed, water within casing52may at least partially freeze due to heat exchange, such as with a heat pump system100. Thus, ice maker50includes heat pump system100for cooling ice maker50. Heat pump system100is in thermal communication with casing52to remove heat from casing52and interior volume56thereof, thus facilitating freezing of water therein to form ice. As shown inFIG. 3, heat pump system100includes a first heat exchanger104in thermal communication with casing52in order to remove heat from interior volume56and water therein during operation of heat pump system100. For example, first heat exchanger104may at least partially surround casing52. In particular, first heat exchanger104may be a conduit coiled around and in contact with casing52, such as the sidewall(s)54thereof. Heat pump system100and components thereof are discussed in greater detail below, in the context ofFIG. 4.

As discussed, in exemplary embodiments, ice18may be nugget ice. Nugget ice is ice that that is maintained or stored (i.e. in first storage volume16of container14) at a temperature greater than the melting point of water or greater than about thirty-two degrees Fahrenheit. Accordingly, the ambient temperature of the environment surrounding the container14may be at a temperature greater than the melting point of water or greater than about thirty-two degrees Fahrenheit. In some embodiments, such temperature may be greater than forty degrees Fahrenheit, greater than fifty degrees Fahrenheit, or greater than sixty degrees Fahrenheit.

Ice18held within the first storage volume16may gradually melt. The melting speed is increased for nugget ice due to the increased maintenance / storage temperature. Accordingly, drain features may advantageously be provided in container14for draining such melt water. Additionally, and advantageously, the melt water may in exemplary embodiments be reused by ice making appliance10to form ice.

In exemplary embodiments, ice making appliance10may further include a controller90. Controller90may for example, be configured to operate ice making appliance10based on, for example, user inputs to ice making appliance10(such as to a user interface thereof), inputs from various sensors disposed within ice making appliance10, and/or other suitable inputs. Controller90may for example include one or more (e.g., non-transitory) memory devices and one or more microprocessors, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with ice making appliance10operation. 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, controller90may 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.

In exemplary embodiments, controller90may be in operative communication with pump32. Such operative communication may be via a wired or wireless connection, and may facilitate the transmittal and/or receipt of signals by controller90and pump32. Controller90may be configured to activate pump32to actively flow liquid water. For example, controller90may activate pump32to actively flow water therethrough when, for example, reservoir34requires water. A suitable sensor(s), for example, may be provided in the third storage volume36. The sensor(s) may be in operative communication with controller90may be transmit signals to controller90which indicate whether or not additional water is desired in reservoir34. When controller90receives a signal that water is desired, controller90may send a signal to pump32to activate pump32.

FIG. 4provides a schematic view of certain components of ice making appliance10including casing52and machinery compartment140. As shown in FIG.4, ice making appliance10includes heat pump system100for heating and/or cooling casing52. Heat pump system100includes a pump102, first heat exchanger104, a heat pump106and a second heat exchanger108. Various components of heat pump system100may be positioned within machinery compartment140below casing52, including pump102, heat pump106and second heat exchanger108, e.g., while first heat exchanger104is positioned on or at casing52above machinery compartment140.

First heat exchanger104is assembled in a heat exchange relationship with casing52in order to heat and/or cool interior volume56of casing52during operation of heat pump system100. Thus, first heat exchanger104may be positioned at or adjacent casing52for the rejection of heat from and/or addition of heat into interior volume56of casing52. A heat transfer fluid such as e.g., an aqueous solution, flowing within first heat exchanger104receives heat from interior volume56of casing52thereby cooling its contents and/or rejects heat to interior volume56of casing52thereby heating its contents. As an example, first heat exchanger104may be a conduit, such as copper or aluminum tubing, wound onto casing52at an outer surface84of casing52. When first heat exchanger104is a conduit wound onto casing52, first heat exchanger104may be brazed, soldered, clipped, adhered or otherwise suitably mounted to casing52at outer surface84of casing52.

First heat exchanger104extends between a first inlet130and a second inlet132. The heat transfer fluid from heat pump106may enter first heat exchanger104at first inlet130of first heat exchanger104and may exit first heat exchanger104at second inlet132of first heat exchanger104in a heating mode. Conversely, in a cooling mode, the heat transfer fluid from heat pump106may enter first heat exchanger104at second inlet132of first heat exchanger104and may exit first heat exchanger104at first inlet130of first heat exchanger104. First inlet130of first heat exchanger104may be positioned at or proximate a top portion80of casing52. Conversely, second inlet132of first heat exchanger104may be positioned at or proximate a bottom portion82of casing52. Thus, first inlet130of first heat exchanger104may be positioned above second inlet132of first heat exchanger104along the vertical direction V on casing52. In such a manner, the heat transfer fluid within first heat exchanger104may first heat top portion80of casing52before flowing downwardly along the vertical direction V to heat bottom portion82of casing52in the heating mode. Conversely, in the cooling mode, the heat transfer fluid within first heat exchanger104may first cool bottom portion82of casing52before flowing upwardly along the vertical direction V to cool top portion80of casing52. In such a manner, efficient heat transfer between the heat transfer fluid within first heat exchanger104and interior volume56of casing52may be facilitated.

First heat exchanger104may be wound onto casing52between first and second inlets130,132of first heat exchanger104. As an example, first heat exchanger104may be wound onto casing52such that adjacent windings of first heat exchanger104are spaced apart from one another along the vertical direction V on outer surface84of casing52, as shown inFIG. 4. In particular, adjacent windings of first heat exchanger104may be uniformly spaced apart from one another along the vertical direction V on outer surface84of casing52. Thus, first heat exchanger104may be wound onto outer surface84of casing52at a constant rate. By uniformly spacing adjacent windings of first heat exchanger104on outer surface84of casing52, uniform heat transfer between the heat transfer fluid within first heat exchanger104and interior volume56of casing52along the vertical direction V may be facilitated.

Operation of heat pump system100in the cooling mode is described in greater detail below. In the cooling mode, the heat transfer fluid flows out of first heat exchanger104by line120to heat pump106after cooling wash chamber106of tub104. As will be further described herein, the heat transfer fluid receives additional heat from magneto-caloric material (MCM) in heat pump106and then flows by line124to pump102and then to second heat exchanger108, e.g., that is disposed within machinery compartment140. The heat transfer fluid within second heat exchanger108rejects heat to the environment, machinery compartment140, and/or another location external to wash chamber106of tub104via second heat exchanger108. A fan112may be used to create a flow of air across second heat exchanger108and thereby improve the rate of heat transfer from the environment.

From second heat exchanger108, the heat transfer fluid returns by line122to heat pump106where, as will be further described below, the heat transfer fluid rejects heat to the MCM in heat pump106. The now cooler heat transfer fluid flows by line126to first heat exchanger104to receive heat from wash chamber106of tub104and repeat the cycle as just described. Pump102connected into line124causes the heat transfer fluid to circulate in heat pump system100. Motor110is in mechanical communication with heat pump106as will further described. During operation of heat pump system100, the heat transfer fluid may not undergo a phase change.

Heat pump system100is provided by way of example only. Other configurations of heat pump system100may be used as well. For example, lines120,122,124and126provide fluid communication between the various components of heat pump system100but other heat transfer fluid recirculation loops with different lines and connections may also be employed. For example, pump102can also be positioned at other locations or on other lines in heat pump system100. Still other configurations of heat pump system100may be used as well. Heat pump106may be any suitable heat pump with MCM. For example, heat pump106may be constructed or arranged in the manner described in U.S. Patent Publication No. 2014/0165594 of Michael Alexander Benedict, which is hereby incorporated by reference in its entirety.

Operation of heat pump system100in the heating mode will now be described. In the heating mode, the heat transfer fluid flows out of first heat exchanger104by line126to heat pump106after heating wash chamber106of tub104. As will be further described herein, the heat transfer fluid rejects additional heat to magneto-caloric material (MCM) in heat pump106and then flows by line122to second heat exchanger108, e.g., that is disposed within machinery compartment140. The heat transfer fluid within second heat exchanger108is heated by the environment, machinery compartment140, and/or another location external to wash chamber106of tub104via second heat exchanger108. Fan112may be used to create a flow of air across second heat exchanger108and thereby improve the rate of heat transfer from the environment.

From second heat exchanger108, the heat transfer fluid returns by line124to pump102and then to heat pump106where, as will be further described below, the heat transfer fluid receives heat from the MCM in heat pump106. The now hotter heat transfer fluid flows by line120to first heat exchanger104to reject heat to wash chamber106of tub104and repeat the cycle as just described.

Ice making appliance10also includes a temperature sensor92. Temperature sensor92is configured for measuring a temperature within interior volume56of casing52. Temperature sensor92can be positioned at any suitable location within ice making appliance10. For example, temperature sensor92may be positioned within interior volume56of casing52or may be mounted to casing52outside of interior volume56of casing52. When mounted to casing52outside of interior volume56of casing52, temperature sensor92can be configured for indirectly measuring the temperature of water within interior volume56of casing52. For example, temperature sensor92can measure the temperature of casing52and correlate the temperature of casing52to the temperature of interior volume56of casing52. Temperature sensor92can be any suitable temperature sensor. For example, temperature sensor92may be a thermocouple or a thermistor.

FIGS. 5 through 8depict various views of an exemplary heat pump200of as may be used with the present subject matter. Thus, heat pump200may be utilized within ice making appliance10as heat pump106. Heat pump200is provided by way of example only and is not intended to limit the present subject matter to any particular heat pump. As will be understood, any other suitable heat pump, such as a linearly actuating heat pump, may be utilized within ice making appliance10as heat pump106in alternative exemplary embodiments.

Heat pump200includes a regenerator housing202that extends longitudinally along an axial direction between a first end218and a second end220. The axial direction is defined by axis A-A about which regenerator housing202is rotatable. A radial direction R is defined by a radius extending orthogonally from the axis of rotation A-A (FIG. 7). A circumferential direction is indicated by arrows C.

Regenerator housing202defines a plurality of chambers204that extend longitudinally along the axial direction defined by axis A-A. Chambers204are positioned proximate or adjacent to each other along circumferential direction C. Each chamber204includes a pair of openings206and208positioned at opposing ends218and220of regenerator housing202.

Heat pump200also includes a plurality of stages212that include MCM. Each stage212is located in one of the chambers204and extends along the axial direction. For the exemplary embodiment shown in the figures, heat pump200includes eight stages212positioned adjacent to each other along the circumferential direction as shown and extending longitudinally along the axial direction. As will be understood by one of skill in the art using the teachings disclosed herein, a different number of stages212other than eight may be used as well.

A pair of valves214and216is attached to regenerator housing202and rotates therewith along circumferential direction C. More particularly, a first valve214is attached to first end218and a second valve216is attached to second end220. Each valve214and216includes a plurality of apertures222and224, respectively. For this exemplary embodiment, apertures222and224are configured as circumferentially-extending slots that are spaced apart along circumferential direction C. Each aperture222is positioned adjacent to a respective opening206of a chamber204. Each aperture224is positioned adjacent to a respective opening208of a chamber204. Accordingly, a heat transfer fluid may flow into a chamber204through a respective aperture222and opening206so as to flow through the MCM in a respective stage212and then exit through opening208and aperture224. A reverse path can be used for flow of the heat transfer fluid in the opposite direction through the stage212of a given chamber204.

Regenerator housing202defines a cavity228that is positioned radially inward of the plurality of chambers204and extends along the axial direction between first end218and second end220. A magnetic element226is positioned within cavity228and, for this exemplary embodiment, extends along the axial direction between first end218and second end220. Magnetic element226provides a magnetic field that is directed radially outward as indicated by arrows M inFIG. 7.

The positioning and configuration of magnetic element226is such that only a subset of the plurality of stages212is within magnetic field M at any one time. For example, as shown inFIG. 7, stages212aand212e are partially within the magnetic field while stages212b,212c, and212dare fully within the magnetic field M created by magnetic element226. Conversely, the magnetic element226is configured and positioned so that stages212f,212g, and212hare completely or substantially out of the magnetic field created by magnetic element226. However, as regenerator housing202is continuously rotated along the circumferential direction as shown by arrow W, the subset of stages212within the magnetic field will continuously change as some stages212will enter magnetic field M and others will exit.

A pair of seals236and238is provided with the seals positioned in an opposing manner at the first end218and second end220of regenerator housing202. First seal236has a first inlet port240and a first outlet port242and is positioned adjacent to first valve214. As shown, ports240and242are positioned 180 degrees apart about the circumferential direction C of first seal214. However, other configurations may be used. For example, ports240and242may be positioned within a range of about 170 degrees to about 190 degrees about the circumferential direction C as well. First valve214and regenerator housing202are rotatable relative to first seal236. Ports240and242are connected with lines120and122(FIG. 5), respectively. As such, the rotation of regenerator housing202about axis A-A sequentially places lines120and122in fluid communication with at least two stages212of MCM at any one time as will be further described.

Second seal238has a second inlet port244and a second outlet port246and is positioned adjacent to second valve216. As shown, ports244and246are positioned180degrees apart about the circumferential direction C of second seal216. However, other configurations may be used. For example, ports244and246may be positioned within a range of about170degrees to about190degrees about the circumferential direction C as well. Second valve216and regenerator housing202are rotatable relative to second seal238. Ports244and246are connected with lines126and124(FIG. 5), respectively. As such, the rotation of regenerator housing202about axis A-A sequentially places lines124and126in fluid communication with at least two stages212of MCM at any one time as will be further described. Notably, at any one time during rotation of regenerator housing202, lines122and126will each be in fluid communication with at least one stage212while lines120and124will also be in fluid communication with at least one other stage212located about 180 degrees away along the circumferential direction.

FIG. 9illustrates an exemplary method using a schematic representation of stage212of MCM in regenerator housing202as it rotates in the direction of arrow W between positions1through8as shown inFIG. 8. As will be understood, other suitable arrangements of heat pump106(e.g., linear motion of stages212of MCM) may be utilized to provide similar heating and cooling of the heat transfer fluid, e.g., via the magneto-caloric effect in stages212of MCM. During step800, stage212is fully within magnetic field M, which causes the magnetic moments of the material to orient and the MCM to heat as part of the magneto-caloric effect. Ordering of the magnetic field is created and maintained as stage212is rotated sequentially through positions2,3, and then4(FIG. 8) as regenerator housing202is rotated in the direction of arrow W. During the time at positions2,3, and4, the heat transfer fluid dwells in the MCM of stage212and, therefore, is heated. More specifically, the heat transfer fluid does not flow through stage212because the openings206,208,222, and224corresponding to stage212in positions2,3, and4are not aligned with any of the ports240,242,244, or246.

In step802, as regenerator housing202continues to rotate in the direction of arrow W, stage212will eventually reach position5. As shown inFIGS. 5 and 8, at position5the heat transfer fluid can flow through the material as first inlet port240is now aligned with an opening222in first valve214and an opening206at the first end218of stage212while second outlet port246is aligned with an opening224in second valve216at the second end220of stage212. As indicated by arrow QH-OUT, heat transfer fluid in stage212, now heated by the MCM, can travel out of regenerator housing202and along line124to the second heat exchanger108. At the same time, and as indicated by arrow QH-IN, heat transfer fluid from first heat exchanger104flows into stage212from line120when stage212is at position5. Because heat transfer fluid from the first heat exchanger104is relatively cooler than the MCM in stage212, the MCM rejects heat to the heat transfer fluid.

Referring again toFIG. 9and step804, as regenerator housing202continues to rotate in the direction of arrow W, stage212is moved sequentially through positions6,7, and8where stage212is completely or substantially out of magnetic field M. The absence or lessening of the magnetic field is such that the magnetic moments of the material become disordered and the MCM absorbs heat as part of the magneto-caloric effect. During the time in positions6,7, and8, the heat transfer fluid dwells in the MCM of stage212and, therefore, is cooled by losing heat to the MCM as the magnetic moments disorder. More specifically, the heat transfer fluid does not flow through stage212because the openings206,208,222, and224corresponding to stage212when in positions6,7, and8are not aligned with any of the ports240,242,244, or246.

Referring to step806ofFIG. 9, as regenerator housing202continues to rotate in the direction of arrow W, stage212will eventually reach position1. As shown inFIGS. 5 and 8, at position1the heat transfer fluid in stage212can flow through the material as second inlet port244is now aligned with an opening224in second valve216and an opening208at the second end220while first outlet port242is aligned with an opening222in first valve214and opening206at first end218. As indicated by arrow QC-OUT, heat transfer fluid in stage212, now cooled by the MCM, can travel out of regenerator housing202and along line126to the first heat exchanger104. At the same time, and as indicated by arrow QC-IN, heat transfer fluid from second heat exchanger108flows into stage212from line122when stage212is at position1. Because heat transfer fluid from the second heat exchanger108is relatively warmer than the MCM in stage212at position1, the MCM will be heated by the heat transfer fluid. The heat transfer fluid now travels along line126to the first heat exchanger104to receive additional heat and thereby cool casing52.

As regenerator housing202is rotated continuously, the above described process of placing stage212in and out of magnetic field M is repeated. Additionally, the size of magnetic field M and regenerator housing202are such that a subset of the plurality of stages212is within the magnetic field at any given time during rotation. Similarly, a subset of the plurality of stages212are outside (or substantially outside) of the magnetic field at any given time during rotation. Additionally, at any given time, there are at least two stages212through which the heat transfer fluid is flowing while the other stages remain in a dwell mode. More specifically, while one stage212is receiving heat through the flow of heat transfer fluid at position1, another stage212is losing heat from the flowing heat transfer fluid at position5, while all remaining stages212are in dwell mode. As such, the system can be operated continuously to provide a continuous recirculation of heat transfer fluid in heat pump system100as stages212are each sequentially rotated through positions1through8.

Utilizing the exemplary method ofFIG. 9, interior volume56of casing52may be cooled by heat transfer fluid within first heat exchanger104. Such cooling of interior volume56of casing52may assist with forming ice on the inner surface of casing52at interior volume56of casing52. As discussed in greater detail below, interior volume56of casing52may also be heated by heat transfer fluid within first heat exchanger104. Such heating of interior volume56of casing52may assist with deicing casing52, e.g., when rotation of auger60is blocked or hindered by ice within interior volume56of casing52.

FIG. 10illustrates an exemplary method using a schematic representation of stage212of MCM in regenerator housing202as it rotates in the direction of arrow W between positions1through8as shown inFIG. 8. To adjust between the operations of heat pump200shown inFIGS. 9 and 10, pump102may be reversed or a valve within heat pump system100may actuated to reverse the direction of heat transfer fluid flow within heat pump system100. Thus, pump102may be a reversible pump in certain exemplary embodiments. In alternative exemplary embodiments, heat pump system100may include a valve(s) for reversing fluid flow through heat pump system100, e.g., rather than reversing the direction of pump102. Thus, heat pump system100may be adjusted between the cooling and heating operations by reversing pump102or actuating suitable valve(s).

During step900, stage212is fully within magnetic field M, which causes the magnetic moments of the material to orient and the MCM to heat as part of the magneto-caloric effect. Ordering of the magnetic field is created and maintained as stage212is rotated sequentially through positions2,3, and then4(FIG. 8) as regenerator housing202is rotated in the direction of arrow W. During the time at positions2,3, and4, the heat transfer fluid dwells in the MCM of stage212and, therefore, is heated. More specifically, the heat transfer fluid does not flow through stage212because the openings206,208,222, and224corresponding to stage212in positions2,3, and4are not aligned with any of the ports240,242,244, or246.

In step902, as regenerator housing202continues to rotate in the direction of arrow W, stage212will eventually reach position5. At position5, the heat transfer fluid can flow through the material as first inlet port240is now aligned with an opening222in first valve214and an opening206at the first end218of stage212while second outlet port246is aligned with an opening224in second valve216at the second end220of stage212. Heat transfer fluid in stage212, now heated by the MCM, can travel out of regenerator housing202and along line120to first heat exchanger104. At the same time, heat transfer fluid from second heat exchanger108flows into stage212from line124when stage212is at position5. Because heat transfer fluid from the second heat exchanger108is relatively cooler than the MCM in stage212, the MCM rejects heat to the heat transfer fluid.

At step904, as regenerator housing202continues to rotate in the direction of arrow W, stage212is moved sequentially through positions6,7, and8where stage212is completely or substantially out of magnetic field M. The absence or lessening of the magnetic field is such that the magnetic moments of the material become disordered and the MCM absorbs heat as part of the magneto-caloric effect. During the time in positions6,7, and8, the heat transfer fluid dwells in the MCM of stage212and, therefore, is cooled by losing heat to the MCM as the magnetic moments disorder. More specifically, the heat transfer fluid does not flow through stage212because the openings206,208,222, and224corresponding to stage212when in positions6,7, and8are not aligned with any of the ports240,242,244, or246.

Referring to step906ofFIG. 10, as regenerator housing202continues to rotate in the direction of arrow W, stage212will eventually reach position1(FIG. 8). At position1, the heat transfer fluid in stage212can flow through the material as second inlet port244is now aligned with an opening224in second valve216and an opening208at the second end220while first outlet port242is aligned with an opening222in first valve214and opening206at first end218. Heat transfer fluid in stage212, now cooled by the MCM, can travel out of regenerator housing202and along line122to the second heat exchanger108. At the same time, heat transfer fluid from first heat exchanger104flows into stage212from line126when stage212is at position5. Because heat transfer fluid from the first heat exchanger104is relatively warmer than the MCM in stage212at position5, the MCM will be heated by the heat transfer fluid. The heat transfer fluid now travels along line122to the second heat exchanger108to receive additional heat.

As will be understood by one of skill in the art using the teachings disclosed herein, the number of stages for housing202, the number of ports in valve214and216, and/or other parameters can be varied to provide different configurations of heat pump200while still providing for continuous operation. For example, each valve could be provided within two inlet ports and two outlet ports so that heat transfer fluid flows through at least four stages212at any particular point in time. Alternatively, regenerator housing202, valves222and224, and/or seals236and238could be constructed so that e.g., at least two stages are in fluid communication with an inlet port and outlet port at any one time. Other configurations may be used as well.

As stated, stage212includes MCM extending along the axial direction of flow. The MCM may be constructed from a single magneto caloric material or may include multiple different magneto caloric materials. By way of example, ice making appliance10may be used in an application where the ambient temperature changes over a substantial range. However, a specific magneto caloric material may exhibit the magneto caloric effect over only a much narrower temperature range. As such, it may be desirable to use a variety of magneto caloric materials within a given stage to accommodate the wide range of ambient temperatures over which ice making appliance10and/or heat pump200may be used.

A motor110is in mechanical communication with regenerator housing202and provides for rotation of housing202about axis A-A. By way of example, motor110may be connected directly with housing202by a shaft or indirectly through a gear box. Other configurations may be used as well.