Patent Publication Number: US-11022358-B2

Title: Direct cooling ice maker

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 15/852,022 filed on Dec. 22, 2017. This application is incorporated herein by reference 
    
    
     FIELD OF THE INVENTION 
     This application relates generally to an ice maker for a refrigeration appliance, and more particularly, to a refrigeration appliance including a direct cooling ice maker. 
     BACKGROUND OF THE INVENTION 
     Conventional refrigeration appliances, such as domestic refrigerators, typically have both a fresh food compartment and a freezer compartment or section. The fresh food compartment is where food items such as fruits, vegetables, and beverages are stored and the freezer compartment is where food items that are to be kept in a frozen condition are stored. The refrigerators are provided with a refrigeration system that maintains the fresh food compartment at temperatures above 0° C., such as between 0.25° C. and 4.5° C. and the freezer compartments at temperatures below 0° C., such as between 0° C. and −20° C. 
     The arrangements of the fresh food and freezer compartments with respect to one another in such refrigerators vary. For example, in some cases, the freezer compartment is located above the fresh food compartment and in other cases the freezer compartment is located below the fresh food compartment. Additionally, many modern refrigerators have their freezer compartments and fresh food compartments arranged in a side-by-side relationship. Whatever arrangement of the freezer compartment and the fresh food compartment is employed, typically, separate access doors are provided for the compartments so that either compartment may be accessed without exposing the other compartment to the ambient air. 
     Such conventional refrigerators are often provided with a unit for making ice pieces, commonly referred to as “ice cubes” despite the non-cubical shape of many such ice pieces. These ice making units normally are located in the freezer compartments of the refrigerators and manufacture ice by convection, i.e., by circulating cold air over water in an ice tray to freeze the water into ice cubes. Storage bins for storing the frozen ice pieces are also often provided adjacent to the ice making units. The ice pieces can be dispensed from the storage bins through a dispensing port in the door that closes the freezer to the ambient air. The dispensing of the ice usually occurs by means of an ice delivery mechanism that extends between the storage bin and the dispensing port in the freezer compartment door. 
     However, for refrigerators such as the so-called “bottom mount” refrigerator, which includes a freezer compartment disposed vertically beneath a fresh food compartment, placing the ice maker within the freezer compartment is impractical. Users would be required to retrieve frozen ice pieces from a location close to the floor on which the refrigerator is resting. And providing an ice dispenser located at a convenient height, such as on an access door to the fresh food compartment, would require an elaborate conveyor system to transport frozen ice pieces from the freezer compartment to the dispenser on the access door to the fresh food compartment. Thus, ice makers are commonly included in the fresh food compartment of bottom mount refrigerators, which creates many challenges in making and storing ice within a compartment that is typically maintained above the freezing temperature of water. 
     There is provided an ice maker including an evaporator coil in direct contact with an ice tray of the ice maker for cooling the ice tray. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with one aspect, there is provided a refrigeration appliance including a fresh food compartment for storing food items in a refrigerated environment having a target temperature above 0° C., a freezer compartment for storing food items in a sub-freezing environment having a target temperature below 0° C., a system evaporator for providing a cooling effect to at least one of the fresh food compartment and the freezer compartment; and an ice maker disposed within the fresh food compartment for freezing water into ice pieces. The ice maker includes an ice mold with an upper surface comprising a plurality of cavities formed therein for the ice pieces, a heater disposed on the ice mold and an ice maker refrigerant tube abutting at least one lateral side surface of the ice mold and cooling the ice mold to a temperature below 0° C. via thermal conduction. 
     The ice maker refrigerant tube of the ice maker may include a first leg and a second leg abutting opposite lateral side surfaces of the ice mold. 
     The refrigeration appliance may also include a retention clip that is secured to the ice mold and which applies a retaining force against the ice maker refrigerant tube to thereby bias the ice maker refrigerant tube into abutment with the lateral side surface. 
     The ice maker refrigerant tube of the refrigeration appliance may include a portion that extends away from ice mold and includes a plurality of cooling fins thereon. A fan may be adapted to convey air across the plurality of cooling fins to thereby provide a cooling airflow throughout the ice maker. 
     The refrigeration appliance may further include a water fill cup formed integrally with the ice mold as a monolithic body. The ice mold and water fill cup may both include a metal material. 
     The refrigeration appliance may further include an ice box evaporator disposed within the ice maker and configured for supplying cooling air to an ice bin of the ice maker, wherein the ice box evaporator is connected to an outlet of the ice maker refrigerant tube. A centrifugal fan may convey air from the ice bin of the ice maker, over the ice box evaporator and back to the ice bin. 
     In accordance with another aspect, there is provided a refrigeration appliance including a fresh food compartment for storing food items in a refrigerated environment having a target temperature above 0° C., a freezer compartment for storing food items in a sub-freezing environment having a target temperature below 0° C., a refrigeration system comprising a system evaporator for providing a cooling effect to at least one of the fresh food compartment and the freezer compartment; and an ice maker disposed within the fresh food compartment for freezing water into ice pieces. The ice maker includes an ice mold with an upper surface comprising a plurality of cavities formed therein for the ice pieces, a heater disposed on the ice mold and at least one passage extending through the ice mold adjacent a lateral side surface of the ice mold for conveying a refrigerant there through and cooling the ice mold to a temperature below 0° C. via thermal conduction. 
     The refrigeration appliance according to this aspect may include a refrigerant tube that is disposed in the at least one passage and has an outer diameter that is substantially equivalent to a diameter of the at least one passage. The ice mold may be over-molded around the refrigerant tube so that the refrigerant tube is thereby encapsulated within the ice mold. 
     The refrigeration appliance may include a water fill cup formed together with the ice mold as a monolithic body. The ice mold and the water fill cup may both include a metal material. 
     The refrigeration appliance may include an ice box evaporator disposed within the ice maker and configured for supplying cooling air to an ice bin of the ice maker, wherein the ice box evaporator is connected to an outlet of the at least one passage in the ice mold. 
     In accordance with yet another aspect, there is provided a refrigeration appliance including a fresh food compartment for storing food items in a refrigerated environment having a target temperature above 0° C., a freezer compartment for storing food items in a sub-freezing environment having a target temperature below 0° C., a system evaporator for providing a cooling effect to at least one of the fresh food compartment and the freezer compartment, an ice maker disposed within the fresh food compartment for freezing water into ice pieces, and a valve. The ice maker includes an ice mold with an upper surface comprising a plurality of cavities formed therein for the ice pieces. An ice maker refrigerant tube cools the ice mold to a temperature below 0° C. via thermal conduction. The valve includes an inlet, a first outlet connected to an inlet of the ice maker refrigerant tube; and a second outlet connected to a bypass line around the ice maker refrigerant tube. The inlet of the valve is connected to the first outlet of the valve when the valve is in a first position such that a refrigerant flows through the ice maker refrigerant tube and the system evaporator, in that order. The inlet of the valve is connected to the second outlet of the valve when the valve is in the second position such that the refrigerant flows through the bypass line and the system evaporator, in that order. 
     In the refrigeration appliance, an ice box evaporator disposed in the bypass line wherein when the valve is in the first position the refrigerant flows only through the ice maker refrigerant tube and the system evaporator, in that order and when the valve is in the second position the refrigerant flows only through the ice box evaporator and the system evaporator, in that order. 
     In the refrigeration appliance, an ice box evaporator connected to an outlet of the ice maker refrigerant tube and the bypass line wherein when the valve is in the first position the refrigerant flows only through the ice maker refrigerant tube, the ice box evaporator and the system evaporator, in that order and when the valve is in the second position the refrigerant flows only through the ice box evaporator and the system evaporator, in that order. 
     The ice maker refrigerant tube of the refrigeration appliance may abut at least one lateral side surface of the ice mold. 
     The ice mold of the refrigerant appliance may include at least one passage extending through the ice mold adjacent a lateral side surface of the ice mold for conveying a refrigerant there through. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a household French Door Bottom Mount showing doors of the refrigerator in a closed position; 
         FIG. 2  is a front perspective view of the refrigerator of  FIG. 1  showing the doors in an open position and an ice maker in a fresh food compartment; 
         FIG. 3  is a side perspective view of an ice maker with a side wall of a frame of the ice maker removed for clarity; 
         FIG. 4A  is a side perspective view of a first embodiment an ice tray assembly for the ice maker of  FIG. 3 ; 
         FIG. 4B  is a bottom perspective view of the ice tray assembly of  FIG. 4A ; 
         FIG. 5  is a section view of the ice tray assembly of  FIG. 4A  taken along line  5 - 5 ; 
         FIG. 6  is a side perspective view of an ice maker evaporator for the ice tray assembly of  FIG. 4 ; 
         FIG. 7  is a top view of a second embodiment of an ice maker evaporator for the ice tray assembly of  FIG. 4 ; 
         FIG. 8  is a side plane view of the ice maker of  FIG. 3  with the ice maker evaporator of  FIG. 7  wherein arrows illustrate an example air circulation path within the ice maker; 
         FIG. 9  is a rear perspective view of a second embodiment of an ice tray assembly; 
         FIG. 10  is a rear perspective view of a third embodiment of an ice tray assembly; 
         FIG. 11  is a schematic of a cooling system for the refrigerator of  FIG. 1 ; 
         FIG. 12  is a side perspective view of the ice maker evaporator of  FIG. 6  and an ice box evaporator illustrating an example flow path of a refrigerant through the ice maker evaporator and the ice box evaporator; 
         FIG. 13  is a side section view taken along line  13 - 13  of  FIG. 3 ; and 
         FIG. 14  is a schematic of a second embodiment cooling system for the refrigerator of  FIG. 1 . 
     
    
    
     DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Referring now to the drawings,  FIG. 1  shows a refrigeration appliance in the form of a domestic refrigerator, indicated generally at  20 . Although the detailed description that follows concerns a domestic refrigerator  20 , the invention can be embodied by refrigeration appliances other than with a domestic refrigerator  20 . Further, an embodiment is described in detail below, and shown in the figures as a bottom-mount configuration of a refrigerator  20 , including a fresh food compartment  24  disposed vertically above a freezer compartment  22 . However, the refrigerator  20  can have any desired configuration including at least a fresh food compartment  24  and an ice maker  50  ( FIG. 2 ), such as a top mount refrigerator (freezer disposed above the fresh food compartment), a side-by-side refrigerator (fresh food compartment is laterally next to the freezer compartment), a standalone refrigerator or freezer, etc. 
     One or more doors  26  shown in  FIG. 1  are pivotally coupled to a cabinet  29  of the refrigerator  20  to restrict and grant access to the fresh food compartment  24 . The door  26  can include a single door that spans the entire lateral distance across the entrance to the fresh food compartment  24 , or can include a pair of French-type doors  26  as shown in  FIG. 1  that collectively span the entire lateral distance of the entrance to the fresh food compartment  24  to enclose the fresh food compartment  24 . For the latter configuration, a center flip mullion  31  ( FIG. 2 ) is pivotally coupled to at least one of the doors  26  to establish a surface against which a seal provided to the other one of the doors  26  can seal the entrance to the fresh food compartment  24  at a location between opposing side surfaces  27  ( FIG. 2 ) of the doors  26 . The mullion  31  can be pivotally coupled to the door  26  to pivot between a first orientation that is substantially parallel to a planar surface of the door  26  when the door  26  is closed, and a different orientation when the door  26  is opened. The externally-exposed surface of the center mullion  31  is substantially parallel to the door  26  when the center mullion  31  is in the first orientation, and forms an angle other than parallel relative to the door  26  when the center mullion  31  is in the second orientation. The seal and the externally-exposed surface of the mullion  31  cooperate approximately midway between the lateral sides of the fresh food compartment  24 . 
     A dispenser  28  ( FIG. 1 ) for dispensing at least ice pieces, and optionally water, can be provided on an exterior of one of the doors  26  that restricts access to the fresh food compartment  24 . The dispenser  28  includes a lever, switch, proximity sensor or other device that a user can interact with to cause frozen ice pieces to be dispensed from an ice bin  54  ( FIG. 2 ) of the ice maker  50  disposed within the fresh food compartment  24 . Ice pieces from the ice bin  54  can exit the ice bin  54  through an aperture  62  and be delivered to the dispenser  28  via an ice chute  32  ( FIG. 2 ), which extends at least partially through the door  26  between the dispenser  28  and the ice bin  54 . 
     Referring to  FIG. 1 , the freezer compartment  22  is arranged vertically beneath the fresh food compartment  24 . A drawer assembly (not shown) including one or more freezer baskets (not shown) can be withdrawn from the freezer compartment  22  to grant a user access to food items stored in the freezer compartment  22 . The drawer assembly can be coupled to a freezer door  21  that includes a handle  25 . When a user grasps the handle  25  and pulls the freezer door  21  open, at least one or more of the freezer baskets is caused to be at least partially withdrawn from the freezer compartment  22 . 
     The freezer compartment  22  is used to freeze and/or maintain articles of food stored in the freezer compartment  22  in a frozen condition. For this purpose, the freezer compartment  22  is in thermal communication with a freezer evaporator  82  ( FIG. 11 ) that removes thermal energy from the freezer compartment  22  to maintain the temperature therein at a temperature of 0° C. or less during operation of the refrigerator  20 , preferably between 0° C. and −50° C., more preferably between 0° C. and −30° C. and even more preferably between 0° C. and −20° C. 
     The refrigerator  20  includes an interior liner  34  ( FIG. 2 ) that defines the fresh food compartment  24 . The fresh food compartment  24  is located in the upper portion of the refrigerator  20  in this example and serves to minimize spoiling of articles of food stored therein. The fresh food compartment  24  accomplishes this by maintaining the temperature in the fresh food compartment  24  at a cool temperature that is typically above 0° C., so as not to freeze the articles of food in the fresh food compartment  24 . It is contemplated that the cool temperature preferably is between 0° C. and 10° C., more preferably between 0° C. and 5° C. and even more preferably between 0.25° C. and 4.5° C. According to some embodiments, cool air from which thermal energy has been removed by the freezer evaporator  82  can also be blown into the fresh food compartment  24  to maintain the temperature therein greater than 0° C. preferably between 0° C. and 10° C., more preferably between 0° C. and 5° C. and even more preferably between 0.25° C. and 4.5° C. For alternate embodiments, a separate fresh food evaporator (not shown) can optionally be dedicated to separately maintaining the temperature within the fresh food compartment  24  independent of the freezer compartment  22 . According to an embodiment, the temperature in the fresh food compartment  24  can be maintained at a cool temperature within a close tolerance of a range between 0° C. and 4.5° C., including any subranges and any individual temperatures falling with that range. For example, other embodiments can optionally maintain the cool temperature within the fresh food compartment  24  within a reasonably close tolerance of a temperature between 0.25° C. and 4° C. 
     An illustrative embodiment of the ice maker  50  is shown in  FIG. 3 . In general, the ice maker  50  includes a frame  52 , an ice bin  54 , an air handler assembly  70  and an ice tray assembly  100 . The ice bin  54  stores ice pieces made by the ice tray assembly  100  and the air handler assembly  70  circulates cooled air to the ice tray assembly  100  and the ice bin  54 . The ice maker  50  is secured within the fresh food compartment  24  using any suitable fastener. The frame  52  is generally rectangular-in-shape for receiving the ice bin  54 . The frame  52  includes insulated walls for thermally isolating the ice maker  50  from the fresh food compartment  24 . A plurality of fasteners (not shown) may be used for securing the frame  52  of the ice maker  50  within the fresh food compartment  24  of the refrigerator  20 . 
     For clarity the ice maker  50  is shown with a side wall of the frame  52  removed; normally, the ice maker  50  would be enclosed by insulated walls. The ice bin  54  includes a housing  56  having an open, front end and an open top. A front cover  58  is secured to the front end of the housing  56  to enclose the front end of the housing  56 . When secured together to form the ice bin  54 , the housing  56  and the front cover  58  define an internal cavity  54   a  of the ice bin  54  used to store the ice pieces made by the ice tray assembly  100 . The front cover  58  may be secured to the housing  56  by mechanical fasteners that can be removed using a suitable tool, examples of which include screws, nuts and bolts, or any suitable friction fitting possibly including a system of tabs allowing removal of the front cover  58  from the housing  56  by hand and without tools. Alternatively, the front cover  58  is non-removably secured in place on the housing  56  using methods such as, but not limited to, adhesives, welding, non-removable fasteners, etc. In various other examples, a recess  59  is formed in a side of the front cover  58  to define a handle that may be used by a user for ease in removing the ice bin  54  from the ice maker  50 . An aperture  62  is formed in a bottom of the front cover  58 . A rotatable auger (not shown) can extend along a length of the ice bin  54 . As the auger rotates, ice pieces in the ice bin  54  are urged ice towards the aperture  62  wherein an ice crusher (not shown) is disposed. The ice crusher is provided for crushing the ice pieces conveyed thereto, when a user requests crushed ice. The augur can optionally be automatically activated and rotated by an auger motor assembly (not shown) of the air handler assembly  70 . The aperture  62  is aligned with the ice chute  32  ( FIG. 2 ) when the door  26  is closed. This alignment allows for the auger to push the frozen ice pieces stored in the ice bin  54  into the ice chute  32  to be dispensed by the dispenser  28 . 
     Referring to  FIGS. 4A and 4B , the ice tray assembly  100  includes an ice mold  102 , a cover  118 , a harvest heater  126  ( FIGS. 4B and 5 ) for partially melting the ice pieces, a plurality of sweeper-arms  132  ( FIG. 5 ) and an ice maker evaporator  150 . The ice mold  102  is preferably made from a thermally conductive metal, like aluminum or steel. It is also preferred that the ice mold  102  is a single monolithic body. 
     Referring to  FIG. 5 , the ice mold  102  includes a top surface  104 , a bottom surface  106  and lateral side surfaces  108 . A plurality of cavities  112  is formed in the top surface  104  of the ice mold  102 . The plurality of cavities  112  is configured for receiving water to be frozen into ice pieces. The plurality of cavities  112  may be defined by weirs  114 , and some or all of the weirs  114  have an aperture therethrough to enable water to flow among the cavities  112 . The cavities  112  can have multiple variants. Different cube shapes and sizes are possible (e.g., crescent, cubical, hemispherical, cylindrical, star, moon, company logo, a combination of shapes and sizes simultaneously, etc.) as long as the ice pieces can be removed by the plurality of sweeper-arms  132 . In the embodiment shown, the plurality of cavities  112  are aligned in a lateral direction of the ice mold  102 . 
     The bottom surface  106  of the ice mold  102  is contoured to receive the harvest heater  126 , as described in detail below. The bottom surface  106  includes a groove  106   a  that extends about a periphery of the bottom surface  106  for receiving the harvest heater  126  therein. 
     The lateral side surfaces  108  are contoured or sculpted to receive the ice maker evaporator  150 . The lateral side surfaces  108  may include elongated recess  108   a  that closely match the outer profile of the ice maker evaporator  150 , as described in detail below. 
     Referring to  FIGS. 4A and 5 , the cover  118  is attached to the top surface  104  of the ice mold  102  for securing the ice tray assembly  100  to the liner  34  of the fresh food compartment  24 . The ice mold  102  may also be attached to an interior of the frame  52  of the ice maker  50  if installed as a unit. The cover  118  includes tabs  118   a  for securing the ice tray assembly  100  to mating openings (not shown) in the liner  34  or in a top wall of the frame  52 . One longitudinal edge  118   b  of the cover  118  is dimensioned to be spaced from an upper edge of the ice mold  102  to define an opening  122 . The opening  122  is dimensioned to allow ice pieces to be ejected from the ice tray assembly  100 , as described in detail below. 
     Referring to  FIGS. 4B and 5 , the harvest heater  126  is attached to the bottom surface  106  of the ice mold  102  to provide a heating effect to the ice mold  102  to thereby separate congealed ice pieces from the ice mold  102  during an ice harvesting operation. The heater  126  may be an electric resistive heater, and may be capture in the groove  106   a  formed in the bottom surface  106  of the ice mold  102 . The heater  126  is configured to be in direct or substantially direct contact with the ice mold  102  for increased conductive heat transfer. In the embodiment shown, the harvest heater  126  is a U-shape element that extends around a periphery of the bottom surface  106  and has a cylindrical outer surface. It is contemplated that the groove  106   a  may have a cylindrical contour that matches the outer cylindrical outer surface of the harvest heater  126 . In the embodiment shown, the legs of the U-shaped heater  126  extend along the lateral direction of the ice mold  102 . It is contemplated the heater  126  may have other shapes, for example, but not limited to, circular, oval, spiral, etc. so long as the heater  126  is disposed in direct or substantially direct contact with the ice mold  102 . 
     The plurality of sweeper-arms  132  are disposed in the cavities  112  formed in the top surface  104  of the ice mold  102 . The plurality of sweeper-arms  132  are elongated elements that are attached to a rotatable shaft  134 . As the shaft  134  rotates the sweeper-arms  132  move through the cavities  112  to force ice pieces in the cavities  112  out of the ice mold  102 . In the embodiment shown in  FIG. 5 , the shaft  134  extends in the lateral direction of the ice mold  102  and is rotatable in a clockwise direction such that the sweeper-arms  132  force the ice pieces into an area above the ice mold  102 . A lower surface of the cover  118  is curved to direct the ice pieces toward the opening  122  between the cover  118  and the ice mold  102 . As the sweeper-arms  132  continue to rotate, the ice pieces are then ejected from the ice tray assembly  100  into the ice bin  54  ( FIG. 3 ) positioned below the ice tray assembly  100 . 
     Prior to actuating the plurality of sweeper-arms  132 , the harvest heater  126  is energized to heat the ice mold  102  which, in turn, melts a lower surface of the ice pieces in the plurality of cavities  112 . A thin layer of liquid is formed on the lower surface of the ice pieces to aid in detaching the ice pieces from the ice mold  102 . The plurality of sweeper-arms  132  may then eject the ice pieces out of the ice mold  102 . 
     In the embodiment shown, the ice mold  102  is a monolithic body that includes an integrally formed water fill cup  136 . It is contemplated that the water fill cup  136  may be made of the same material as the ice mold  102 . In particular, it is contemplated that the ice mold  102  may be made of a metal material, e.g., aluminum or steel. The fill cup  136  includes side and bottom walls that are planar and sloped toward the cavities  112  in the ice mold  102 . As such, water injected into the fill cup  136  will flow, by gravity to the cavities  112  in the ice mold  102 . It is contemplated that the thermal energy provided by the harvest heater  126  may also be sufficient to melt frost or ice that may accumulate on the fill cup  136  during normal operation. Referring to  FIG. 6 , the ice maker evaporator  150  includes a first leg  152 , a second leg  154  and a connecting portion  156 . In the embodiment shown, the first leg  152  is U-shaped and includes an upper portion  152   a  and a lower portion  152   b . Similarly, the second leg  154  is U-shaped and includes an upper portion  154   a  and a lower portion  154   b . The upper portions  152   a ,  154   a  and the lower portions  152   b ,  154   b  are illustrated in  FIG. 6  as straight elongated elements that extend along the lateral direction of the ice mold  102 . It is contemplated that these portions  152   a ,  154   a ,  152   b ,  154   b  can have other shapes, e.g., curved, wavy, tooth-shaped, stepped, etc. so long as these portions  152   a ,  154   a ,  152   b ,  154   b  are in intimate or surface-to-surface contact with the respective lateral side surfaces  108  of the ice mold  102 . In the embodiment shown, the ice maker evaporator  150  has a U-shape. It is contemplated that the ice maker evaporator  150  may have other shapes so long as the ice maker evaporator  150  is in intimate contact with the ice mold  102 . 
     The ice maker evaporator  150  includes an inlet end  162  for allowing a refrigerant to be injected into the ice maker evaporator  150  and an outlet end  164  for allowing the refrigerant to exit the ice maker evaporator  150 . A first capillary tube  98  (described in detail below) is attached to the inlet end  162 . 
     Referring to  FIG. 5 , in the embodiment shown, the ice maker evaporator  150  has a cylindrical outer surface and the respective recesses  108   a  formed in the lateral side surfaces  108  of the ice mold  102  have a matching contour. In the embodiment shown, the recesses  108   a  are contoured to preferably contact at least half or 180° of the cylindrical outer surface of the first and second legs  152 ,  154  of the ice maker evaporator  150 . It is contemplated that the amount of contact may be more or less than half or 180°. 
     Retention clips  172  are provided for applying a retaining force to the ice maker evaporator  150  for securing the ice maker evaporator  150  into both lateral side surfaces  108  of the ice mold  102 . In the embodiment shown, the clips  172  include an upper end  174  that is shaped for engaging a slotted opening  108   b  in the lateral side surface  108  of the ice mold  102 . A lower end  176  of the clip  172  is shaped for allowing the clip  172  to attach to the bottom surface  106  of the ice mold  102 . In the embodiment shown, the upper end  174  is J-shaped for securing the clip  172  to the slotted opening  108   b  and the lower end  176  is S-shaped to attach the clip  172  to an elongated rib  106   b  extending along opposite edges of the bottom surface  106  of the ice mold  102 . The clip  172  is installed by inserting the upper end  174  into the slotted opening  108   b  and then rotating the clip  172  toward the ice mold  102  until the lower end  176  snaps or clips onto the elongated rib  106   b , or an equivalent feature of the ice mold  102 . The clips  172  are dimensioned and positioned to bias or maintain the ice maker evaporator  150  in intimate contact or abutment with the lateral side surfaces  108  of the ice mold  102 . It is contemplated that the ice maker evaporator  150  may be configured to snap into the respective recesses  108   a  on the lateral side surfaces  108  of the ice mold  102 . 
     Referring to  FIG. 7 , according to another embodiment, the ice maker evaporator  150  may include a plurality of cooling fins  182 . Referring to  FIG. 8 , when the ice maker evaporator  150  is disposed in the ice maker  50  the plurality of fins  182  may be positioned in the air handler assembly  70  proximate a circulation fan  184 . When the fan  184  is energized, air is conveyed over the plurality of fins  182  and cooled air is circulated into the ice maker  50 . Preferably, the cooled air is conveyed to the ice bin  54  to keep the ice pieces therein cold. Arrows in  FIG. 8  illustrate the path of the air circulated within the ice maker  50  from the circulation fan conveying air over the ice maker evaporator  150 . 
     Referring to  FIG. 9 , a second embodiment ice tray assembly  200  similar to ice tray assembly  100  is shown. The second ice tray assembly  200  includes an ice mold  202 . The second ice tray assembly  200  includes other components that are similar or identical to the ice tray assembly  100 , but these components are not shown or described in detail below. For example, similar to the ice mold  102 , the ice mold  202  includes a plurality of cavities (not shown) that are configured for receiving water to be frozen into ice pieces. 
     The ice mold  202  includes elongated internal cavities  202   a  that extend along at least one, and preferably opposite sides of the ice mold  202  in the lateral direction of the ice mold  202 . The elongated cavities  202   a  are dimensioned and positioned to receive the first leg  152  and preferably also the second leg  154  of the ice maker evaporator  150 . The ice mold  202  includes a rear surface  202   b  that is contoured to receive the connecting portion  156  of the ice maker evaporator  150  when the ice maker evaporator  150  is fully inserted into the cavities  202   a . A clip or fastener (not shown) may be used for securing the ice maker evaporator  150  to the ice mold  202 . In the first embodiment ice tray assembly  100  described above, the first leg  152  and the second leg  154  of the ice maker evaporator  150  are positioned on external surfaces of the ice mold  102 . In the second embodiment ice tray assembly  200 , the first leg  152  and the second leg  154  of the ice maker evaporator  150  are positioned inside the ice mold  202 . 
     Referring to  FIG. 10 , a third embodiment ice tray assembly  300  similar to the ice tray assembly  100  is shown. The third ice tray assembly  300  includes an ice mold  302 . The third ice tray assembly  300  includes other components that are identical to the ice tray assembly  100 , but these components are not shown or described in detail below. For example, similar to the ice mold  102 , the ice mold  302  includes a plurality of cavities (not shown) that are configured for receiving water to be frozen into ice pieces. Similar to the second embodiment ice tray assembly  200 , the third embodiment ice tray assembly  300  includes tubes  303  that are positioned inside the ice mold  302 . 
     The ice mold  302  is a cast or molded block of metal, e.g., aluminum or steel that is cast around tubes  303  in a manner similar to an over-molding technique typically used in polymer manufacturing. The tubes  303  may be made from stainless steel or another high temperature material that withstands the heat required for casting the metal ice mold  302 . Connectors (not shown) may be attached to the tubes  303  for fluidly connecting the tubes  303  to the cooling system of the refrigerator  20 . In the embodiment shown, the tubes  303  are disposed along one side of the ice mold  302 . The tubes  303  are connected by an internal U-channel (not shown). It is contemplated that the tubes  303  may also be disposed on the opposite lateral sides of the ice mold  302 . The tubes  303 , when connected to each other and the cooling system define a third ice maker evaporator  350 . It is contemplated that the tubes  303  may be inserted into one or more holes (not shown) wherein an outer diameter of the tubes  303  is substantially equivalent to a diameter of the holes such that the tubes  303  are in intimate contact with the ice mold  302 . It is also contemplated that the tubes  303  may be include threads for threading the tubes  303  into the ice mold  302 . In the embodiment shown, the tubes  303  are parallel to a lower surface of the mold. It is contemplated that the tubes  303  may be sloped or angled relative to the lower surface of the mold. 
     It is also contemplated that instead of placing the tubes  303  in the ice mold  302  a plurality of passages (not shown) may be formed in the ice mold  302  itself and may extend through the ice mold  302  to define a flow path for the refrigerant. Appropriate connectors would be attached to the ice mold  302  itself for fluidly connecting the passages in the ice mold  302  to the appropriate portions of the cooling system of the refrigerator. As such, the ice mold  302  itself defines the ice maker evaporator  350 . 
     The ice tray assemblies  100 ,  200 ,  300  of the instant application employ a direct cooling approach, in which the ice maker evaporators  150 ,  350  are in direct (or substantially direct) contact with the ice mold  102 ,  202 ,  302 . The ice pieces are made without cold air ducted from a remote location (e.g., a freezer) to create or maintain the ice. It is understood that direct contact is intended to mean that the ice maker evaporator  150 ,  350  abuts the ice mold  102 ,  202 ,  302 . Additionally, although no air is typically ducted from a remote location (e.g., a freezer) to create or maintain the ice, it is contemplated that cold air could be ducted from another location, such as about the system evaporator (not shown), if desired to increase a rate of ice making production or to maintain the stored ice pieces in the ice bin  54  at a frozen state. This could be useful, for example, in a configuration where the ice bin  54  is separated or provided at a distance apart from the ice maker evaporator  150 ,  350 , or where accelerated ice formation is desired. 
     Still, although the term “evaporator” is used for simplicity, in yet another embodiment the ice maker evaporator  150 ,  350  could instead be a thermoelectric element (or other cooling element) that is operable to cool the ice mold  102 ,  202 ,  302  to a sufficient amount to congeal the water into ice pieces. Similar operative service lines (such as electrical lines) can be provided similar to the inlet/outlet lines described above. 
     Referring to  FIG. 11 , a schematic of a cooling system  80  for the refrigerator  20  is shown. The cooling system  80  includes conventional components, such as a freezer evaporator  82 , an accumulator  84  (optional), a compressor  86 , a condenser  88  and a dryer  92 . These components are conventional components that are well known to those skilled in the art and will not be described in detail herein. 
     The ice maker evaporator  150 ,  350  is connected between a valve  94  and an ice box evaporator  96 . It is contemplated that both the valve  94  and the dryer  92  may be positioned in a machine room (not shown) of the refrigerator  20 . The valve  94  includes a single inlet  94   a  and two outlets  94   b ,  94   c . The inlet  94   a  is connected to the condenser  88  and optionally to the dryer  92 . A first outlet  94   b  is connected to the ice maker evaporator  150 ,  350  (represented by arrow “A”). The first capillary tube  98  connects the first outlet  94   b  of the valve  94  to the ice maker evaporator  150 ,  350 . A second outlet  94   c  is connected to the ice box evaporator  96  (represented by arrow “B”). A second capillary tube  99  connects the second outlet  94   c  of the valve  94  to the ice box evaporator  96 . It is contemplated that the ice box evaporator  96  is an optional component. For example, the ice maker evaporator  96  may not be required if the ice maker evaporator  150  includes the cooling fins  182  that are sufficiently configured to maintain the ice pieces in the ice bin  54  at the desired temperature. 
       FIG. 12  shows one embodiment wherein the ice maker evaporator  150  is connected to the ice box evaporator  96 . When the valve  94  is in a first position (i.e., in through the inlet  94   a  and out through the first outlet  94   b ) the refrigerant flows along the flow path “A” through the first capillary tube  98  and enters the inlet end  162  of the ice maker evaporator  150 , flows through the ice maker evaporator  150 , exits the outlet end  164 , enters an inlet end  96   a  of the ice box evaporator  96 , flows through the ice box evaporator  96  and exits an outlet end  96   b  of the ice box evaporator  96  (represented by arrow “C”). When the valve  94  is in a second position (i.e., in through the inlet  94   a  and out through the second outlet  94   c ), the refrigerant flows along the flow path “B” through the second capillary tube  99  and enters the inlet end  96   a  of the ice box evaporator  96 , flows through the ice box evaporator  96  and exits the outlet end  96   b  of the ice box evaporator (represented by arrow “C”). As such, when the valve  94  is in the second position the refrigerant bypasses the ice maker evaporator  150 . 
     During an ice harvesting process, a full bucket mode, a defrosting of the ice box evaporator  96  or when the ice maker  50  is “OFF,” the valve  94  is in the second position such that the second outlet  94   c  is fluidly connected to the ice box evaporator  96  and the refrigerant bypasses the ice maker evaporator  150 ,  350 . During other processes/modes of operation, the valve  94  is in the first position such that the first outlet  94   b  of the valve  94  is connected to the ice maker evaporator  150 ,  350  and the refrigerant flows through the ice maker evaporator  150 ,  350  and then to the ice box evaporator  96 . 
       FIG. 14  illustrates a second embodiment wherein the ice box evaporator  96  and the ice maker evaporator  150 ,  350  are disposed in parallel paths. The ice maker evaporator  150 ,  350  is connected to the first outlet  94   b  of the bistable valve  94  by the first capillary tube  98  and the ice box evaporator  96  is connected to the second outlet  94   c  of the bistable valve  94  by the second capillary tube  99 . When the valve  94  is in a first position (i.e., in through the inlet  94   a  and out through the first outlet  94   b ) the refrigerant flows along the flow path “A” through the first capillary tube  98  and the ice maker evaporator  150 . When the valve  94  is in a second position (i.e., in through the inlet  94   a  and out through the second outlet  94   c ), the refrigerant flows along the flow path “B” through the second capillary tube  99  and the ice box evaporator  96 . As such, when the valve  94  is in the second position the refrigerant bypasses the ice maker evaporator  150  and when the valve  94  is in the first position the refrigerant bypasses the ice box evaporator  96 . As shown in  FIG. 14 , the ice box evaporator  96  is disposed in a bypass line or path around the ice maker evaporator  150 ,  350 . Alternatively, the ice maker evaporator  150 ,  350  is disposed in a bypass line or path around the ice box evaporator  96 . 
     During an ice harvesting process, a full bucket mode, a defrosting of the ice box evaporator  96  or when the ice maker  50  is “OFF,” the valve  94  is in the second position such that the second outlet  94   c  is fluidly connected to the ice box evaporator  96  and the refrigerant bypasses the ice maker evaporator  150 ,  350 . During other processes/modes of operation, the valve  94  is in the first position such that the first outlet  94   b  of the valve  94  is connected to the ice maker evaporator  150 ,  350  and bypasses the ice box evaporator  96 . 
     The switching of the valve  94  is designed to reduce the operational cost of the cooling system  80  for the ice maker  50 . For simplicity, the housing of the air handler assembly  70  is not shown in  FIG. 12 . Arrows in  FIG. 12  illustrate that path of the refrigerant through the ice maker evaporator  150  and the ice box evaporator  96 . 
     It is contemplated that the valve  94  may be, such as but not limited to, a bistable valve, a stepper valve or an electronic expansion valve that is configured to control the flow of refrigerant entering the ice maker evaporator  150 ,  350 . The bistable valve may be a binary valve, i.e., an “either/or” valve wherein 100% of the flow exits through either the first outlet  94   b  or the second outlet  94   c . The electronic expansion valve allows the flow of refrigerant to the ice maker evaporator  150 ,  350  independently of the flow of the refrigerant to the ice box evaporator  96 . Thus, the flow of refrigerant to the ice maker evaporator  150 ,  350  can be discontinued as appropriate during ice making even though the compressor  86  is operational and refrigerant is being delivered to the ice box evaporator  96 . Additionally, the opening and closing of the electronic expansion valve can be controlled to regulate the temperature of at least one of the ice maker evaporator  150 ,  350  and the ice box evaporator  96 . A duty cycle of the electronic expansion valve, in addition to or in lieu of the operation of the compressor  86 , can be adjusted to change the amount of refrigerant flowing through the ice maker evaporator  150 ,  350  based on the demand for cooling. There is a greater demand for cooling by the ice maker evaporator  150 ,  350  while water is being frozen to form the ice pieces than there is when the ice pieces are not being produced. It is therefore possible to avoid changing the operation of the compressor  86  while the electronic expansion valve is operational to account for the needs of the ice maker evaporator  150 ,  350 . 
     When ice is to be produced by the ice maker  50 , a controller (not shown) can at least partially open the electronic expansion valve. After passing through the electronic expansion valve the refrigerant enters the ice maker evaporator  150 ,  350  where it expands and at least partially evaporates into a gas. The latent heat of vaporization required to accomplish the phase change is drawn from the ambient environment of the ice maker evaporator  150 ,  350 , thereby lowering the temperature of an external surface of the ice maker evaporator  150 ,  350  to a temperature that is below 0° C. The temperature of the portion of the ice molds  102 ,  202 ,  302  exposed to the external surface of the ice maker evaporator  150 ,  350  decreases thereby causing water in the cavities  112  to freeze and form the ice pieces. 
     Referring to  FIG. 13 , the ice maker  50  includes a circulation fan  64 . The ice box evaporator  96  is disposed proximate the circulation fan  64  such that air is drawn from the ice bin  54 , over the ice box evaporator  96  and back to the ice bin  54 . It is contemplated that the circulation fan  64  may be a centrifugal or squirrel-cage type fan wherein air is drawn into a center of the fan  64  and then exhausted radially away from the fan. It is also contemplated that the circulation fan  64  may be an axial fan wherein air is conveyed through the fan along a rotational axis of the fan. It is contemplated that the ice box evaporator  96  may include a heater  97  ( FIG. 12 ) that may be energized during a defrost cycle of the ice box evaporator  96 . The heater may be configured such that heat generated by the heater is sufficient to defrost both the ice box evaporator  96  and the fill cup  136  ( FIG. 5 ) of the ice tray assembly  100 . 
     The dedicated ice maker evaporator  150 ,  350  removes thermal energy from water in the ice mold  102 ,  202 ,  302  to create the ice pieces. As described previously herein, the ice maker evaporator  150 ,  350  may be configured to be a portion of the same refrigeration loop as the freezer evaporator  82  that provides cooling to the freezer compartment  22  of the refrigerator  20 . In various examples, the ice maker evaporator  150 ,  350  can be provided in serial or parallel configurations with the freezer evaporator  82 . In yet another example, the ice maker evaporator  150 ,  350  can be configured as a completely independent refrigeration system. 
     In addition or alternatively, the ice maker of the present application may further be adapted to mounting and use on a freezer door. In this configuration, although still disposed within the freezer compartment, at least the ice maker (and possibly an ice bin) is mounted to the interior surface of the freezer door. It is contemplated that the ice mold and ice bin can be separated elements, in which one remains within the freezer cabinet and the other is on the freezer door. 
     Cold air can be ducted to the freezer door from an evaporator in the fresh food or freezer compartment, including the system evaporator. The cold air can be ducted in various configurations, such as ducts that extend on or in the freezer door, or possibly ducts that are positioned on or in the sidewalls of the freezer liner or the ceiling of the freezer liner. In one example, a cold air duct can extend across the ceiling of the freezer compartment, and can have an end adjacent to the ice maker (when the freezer door is in the closed condition) that discharges cold air over and across the ice mold. If an ice bin is also located on the interior of the freezer door, the cold air can flow downwards across the ice bin to maintain the ice pieces at a frozen state. The cold air can then be returned to the freezer compartment via a duct extending back to the evaporator of the freezer compartment. A similar ducting configuration can also be used where the cold air is transferred via ducts on or in the freezer door. The ice mold can be rotated to an inverted state for ice harvesting (via gravity or a twist-tray) or may include a sweeper-finger type, and a heater can be similarly used. It is further contemplated that although cold air ducting from the freezer evaporator as described herein may not be used, a thermoelectric chiller or other alternative chilling device or heat exchanger using various gaseous and/or liquid fluids could be used in its place. In yet another alternative, a heat pipe or other thermal transfer body can be used that is chilled, directly or indirectly, by the ducted cold air to facilitate and/or accelerate ice formation in the ice mold. Of course, it is contemplated that the ice maker of the instant application could similarly be adapted for mounting and use on a freezer drawer. 
     Alternatively, it is further contemplated that the ice maker of the instant application could be used in a fresh food compartment, either within the interior of the cabinet or on a fresh food door. It is contemplated that the ice mold and ice bin can be separated elements, in which one remains within the fresh food cabinet and the other is on the fresh food door. 
     In addition or alternatively, cold air can be ducted from another evaporator in the fresh food or freezer compartment, such as the system evaporator. The cold air can be ducted in various configurations, such as ducts that extend on or in the fresh food door, or possibly ducts that are positioned on or in the sidewalls of the fresh food liner or the ceiling of the fresh food liner. In one example, a cold air duct can extend across the ceiling of the fresh food compartment, and can have an end adjacent to the ice maker (when the fresh food door is in the closed condition) that discharges cold air over and across the ice mold. If an ice bin is also located on the interior of the fresh food door, the cold air can flow downwards across the ice bin to maintain the ice pieces at a frozen state. The cold air can then be returned to the fresh food compartment via a ducting extending back to the compartment with the associated evaporator, such as a dedicated icemaker evaporator compartment or the freezer compartment. A similar ducting configuration can also be used where the cold air is transferred via ducts on or in the fresh food door. The ice mold can be rotated to an inverted state for ice harvesting (via gravity or a twist-tray) or may include a sweeper-finger type, and a heater can be similarly used. It is further contemplated that although cold air ducting from the freezer evaporator (or similarly a fresh food evaporator) as described herein may not be used, a thermoelectric chiller or other alternative chilling device or heat exchanger using various gaseous and/or liquid fluids could be used in its place. In yet another alternative, a heat pipe or other thermal transfer body can be used that is chilled, directly or indirectly, by the ducted cold air to facilitate and/or accelerate ice formation in the ice mold. Of course, it is contemplated that the ice maker of the instant application could similarly be adapted for mounting and use on a fresh food drawer. 
     The invention has been described with reference to the example embodiments described above. Modifications and alterations will occur to others upon a reading and understanding of this specification. Examples embodiments incorporating one or more aspects of the invention are intended to include all such modifications and alterations insofar as they come within the scope of the appended claims.