Patent Publication Number: US-2023137486-A1

Title: An ice maker for a refrigerator and method for synchronizing an implementation of an ice making cycle and an implementation of a defrost cycle of an evaporator in a refrigerator

Description:
FIELD OF THE INVENTION 
     This application relates generally to an ice maker for a refrigerator, and more particularly, an ice maker comprising an air handler having an outlet diffuser that is disposed adjacent an air inlet in an ice maker frame, and a method for synchronizing an implementation of an ice making cycle with an implementation of a defrost cycle of an evaporator of the refrigerator. 
     BACKGROUND OF THE INVENTION 
     Conventional refrigeration applications, such as domestic refrigerators, typically have ice makers that produce ice pieces for user consumption. Such ice makers generally include a fan configured to direct a flow of cool air toward an ice tray positioned within the ice maker. The flow of air directed from the fan to the ice tray is often rebounded due to obstacles positioned within the direction of the airflow path. As such, the airflow often does not engage the entirety of the ice tray. Moreover, due to conventional fan configurations, a vortex in the airflow may occur, which also results in the entirety of the ice tray not being “washed” with the flow of cool air. 
     Furthermore, the forming and harvesting of such ice pieces are generally dependent on several variables, such as temperature and time. Refrigerators that employ ice makers often include an evaporator that cools the air within the ice maker. This evaporator may be specific to the ice maker (i.e., provides cool air to only the ice maker) or may be associated with other storage compartments of the refrigerator. Additionally, defrost systems are also included and are configured to defrost the evaporator. Such defrost systems provide heat to the evaporator to remove any frost formed thereon. 
     If the defrost system is operational while the ice maker is manufacturing ice pieces, then the above-mentioned variables may be negatively affected such that harvesting of the ice pieces is delayed. Moreover, the heat generated by the defrost system may inadvertently raise the temperature of the harvested ice pieces as well as the structural components of the ice maker and/or ice bin. As such, all warmed components of the ice maker must be cooled down to proper operational temperatures during the ice making cycle. To accomplish this, additional time and cold air are required. Accordingly, implementation of the defrost system during ice piece manufacturing negatively impacts the overall efficiency of the ice forming process. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with one aspect, there is provided an ice maker for a refrigeration appliance. The ice maker comprises an ice maker frame that extends between a first end and a second end. The ice maker frame includes an air inlet provided at the first end of the ice maker frame. An ice tray is rotatably secured to the ice maker frame and is configured to form ice pieces therein. The ice maker further comprises an air handler including an outlet diffuser having a central body defined by a first wall. The first wall is peripherally surrounded by, and radially spaced apart from, a second wall. A plurality of radially extending fins are disposed between the first wall and the second wall. Each of the plurality of radially extending fins is spaced apart, one from the other, along an outer peripheral surface of the first wall. In an installed position, the outlet diffuser is disposed directly adjacent the air inlet provided at the first end of the ice maker frame. 
     The central body is provided at a radial center of the outlet diffuser. Additionally, the air inlet of the ice maker frame comprises a first wall that is peripherally surrounded by, and radially spaced apart from, a second wall, and a projection rib that radially extends between the first and second walls of the air inlet. The first wall of the outlet diffuser and the first wall of the air inlet are both cylindrical in shape, and the first wall of the outlet diffuser is axially aligned with the first wall of the air inlet. The second wall of the outlet diffuser is peripherally surrounded by the second wall of the air inlet. Moreover, the ice maker frame further comprises a cylindrical connection member that is peripherally surrounded by the first wall of the air inlet, the cylindrical connection member being configured to receive a pin of the ice tray in order to rotatably support the ice tray. 
     Still further, the air handler further comprises a housing, and the outlet diffuser is formed integral with the housing. A fan is disposed within the housing. The fan is configured to direct an airflow out of the outlet diffuser and into the air inlet of the ice maker frame. The fan includes a blade having a pitch that is opposite to a pitch of each of the plurality of radially extending fins of the outlet diffuser. Additionally, an evaporator and a defrost heater are further disposed within the housing. 
     In accordance with another aspect, there is provided a refrigeration appliance comprising an inner liner that defines a storage compartment and an outer cabinet that partially encloses the inner liner. A door is connected to the cabinet and is configured to provide selective access to the storage compartment. An ice maker is provided within the storage compartment and is configured to manufacture ice pieces. 
     The ice make comprises an ice maker frame extending between a first end and a second end. The ice maker frame includes an air inlet provided at the first end of the ice maker frame. An ice tray is rotatably secured to the ice maker frame and is configured to form ice pieces therein. The ice maker further comprises an air handler including an outlet diffuser having a central body defined by a first wall. The first wall is peripherally surrounded by, and radially spaced apart from, a second wall. A plurality of radially extending fins are disposed between the first wall and the second wall. Each of the plurality of radially extending fins is spaced apart, one from the other, along an outer peripheral surface of the first wall. Further, in an installed position, the outlet diffuser is disposed directly adjacent the air inlet provided at the first end of the ice maker frame. 
     Additionally, the storage compartment comprises a fresh food compartment and a freezer compartment. The fresh food compartment is disposed vertically above the freezer compartment and is separated therefrom via a horizontal mullion. The ice maker is provided within the fresh food compartment. 
     Moreover, the air inlet of the ice maker frame further comprises a first wall that is peripherally surrounded by, and radially spaced apart from, a second wall. The first wall of the outlet diffuser and the first wall of the air inlet are both cylindrical in shape. The first wall of the outlet diffuser is axially aligned with the first wall of the air inlet, and the central body is provided at a radial center of the outlet diffuser. The second wall of the outlet diffuser is peripherally surrounded by the second wall of the air inlet. 
     Further still, the air handler further comprises a housing that houses a fan configured to direct an airflow out of the outlet diffuser and into the air inlet of the ice maker frame. The fan includes a blade having a pitch that is opposite to a pitch of each of the plurality of radially extending fins of the outlet diffuser. 
     In accordance with yet a further aspect, there is provided an ice maker for a refrigeration appliance. The ice maker includes an ice maker frame having an air inlet provided at a first end thereof. The air inlet comprises a first wall peripherally surrounded by, and radially spaced apart from, a second wall, wherein a projection rib radially extends from the first wall to the second wall of the air inlet. A cylindrical connection member is peripherally surrounded by the first wall of the air inlet. The ice maker further includes an ice tray configured to form ice pieces therein. The ice tray has a first end including a pin. The pin is received within the cylindrical connection member of the air inlet to rotatably secure the ice tray to the ice maker frame. The ice maker also includes an air handler comprising a housing having an outlet diffuser integrally formed therewith. The outlet diffuser comprises a central body provided at a radial center of the outlet diffuser. The central body is defined by a first wall, the first wall being peripherally surrounded by, and radially spaced apart from, a second wall, wherein a plurality of radially extending fins are disposed between the first wall and the second wall. Each of the plurality of radially extending fins is spaced apart, one from the other, along an outer peripheral surface of the first wall. 
     The first wall of the outlet diffuser and the first wall of the air inlet are both cylindrical in shape. The first wall of the outlet diffuser is axially aligned with the first wall of the air inlet, and the second wall of the outlet diffuser is peripherally surrounded by the second wall of the air inlet. A fan is disposed within the housing and includes a blade having a pitch that is opposite to a pitch of each of the plurality of radially extending fins of the outlet diffuser such that, during an operating state of the fan, the fan is configured to direct an airflow out of the outlet diffuser and into the air inlet of the ice maker frame in a substantially linear direction. 
     In accordance with another aspect, there is provided a method for synchronizing an implementation of an ice making cycle of an ice making unit of a refrigerator and an implementation of a defrost cycle of an evaporator or evaporators associated with the ice making unit and the refrigerator. The ice making cycle includes a filling phase, a freezing phase, and a harvesting phase. The method comprises the steps of determining whether an upcoming defrost cycle is scheduled to begin when an ice making unit is in a first portion of an ice making cycle or a second portion of the ice making cycle. 
     If the upcoming defrost cycle is scheduled to begin when the ice making unit is in the second portion of the ice making cycle, then the method further comprises the step of delaying initiation of the upcoming defrost cycle until after the ice making cycle has finished. Alternatively, if the upcoming defrost cycle is scheduled to begin when the ice making unit is in the first portion of the ice making cycle, then the method further comprises the step of immediately initiating the upcoming defrost cycle by energizing a heating element. 
     Further, the ice making unit is disposed in one of a fresh food compartment or a freezer compartment of the refrigerator. Additionally, a duration of time between the upcoming defrost cycle and a previous defrost cycle is equal to or greater than a predetermined minimum duration of time. The predetermined minimum duration of time is based on a minimum operating time of a compressor associated with the refrigerator. 
     Moreover, the step of delaying initiation of the upcoming defrost cycle until after the ice making cycle has finished includes repeated inquiries to the ice making unit from a controller of the refrigerator. The repeated inquiries are performed periodically until it is determined that the ice making unit is not in the freezing phase, the harvesting phase, or the ice filling phase of the ice making cycle. 
     Additionally, the method further comprises a step of determining if the step of delaying initiation of the upcoming defrost cycle exceeds a predetermined maximum period of time. If it is determined that the predetermined maximum period of time has been exceeded, then aborting the ice making cycle and immediately initiating the upcoming defrost cycle. 
     Further yet, before the step of determining whether the upcoming defrost cycle is scheduled to begin when the ice making unit is in the first portion of the ice making cycle or the second portion of the ice making cycle, a controller calculates a time until the upcoming defrost cycle is scheduled to begin. Only if the calculated time is less than or equal to a predetermined time does the step of determining whether the upcoming defrost cycle is scheduled to begin when the ice making unit is in the first portion of the ice making cycle or the second portion of the ice making cycle occur. 
     Moreover, the step of determining whether the ice making unit is in the first portion of the ice making cycle or the second portion of the ice making cycle is performed by a controller. The first portion of the ice making cycle comprising at least one of a filling phase, a freezing phase, and a harvesting phase, and wherein the second portion of the ice making cycle comprises the others of the filling phase, the freezing phase, and the harvesting phase. Alternatively, the first portion of the ice making cycle comprises a first half of time of an overall operation time of the ice making cycle, and the second portion of the ice making cycle comprises a second, subsequent half of time of the overall operation time of the ice making cycle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a front perspective view of a refrigerator; 
         FIG.  2    is a front perspective view of the refrigerator in  FIG.  1    showing doors of a fresh food compartment in an opened position and a door of a freezer compartment removed; 
         FIG.  3    is a partial, front sectional view of an interior of an upper portion of a refrigerator showing an ice maker; 
         FIG.  4    is a front perspective view of an air handler system of the ice maker shown in  FIG.  3   ; 
         FIG.  5    is a rear perspective view of an ice maker frame of the ice maker shown in  FIG.  3   ; 
         FIG.  6    is a perspective cross-sectional view of the ice maker frame installed adjacent the air handler system; 
         FIG.  7    is a side cross-sectional view of the ice maker frame installed adjacent the air handler system; 
         FIG.  8    is a flow chart of an ice making cycle for the ice maker shown in  FIG.  3   ; 
         FIG.  9    is a flow chart illustrating synchronizing an implementation of an ice making cycle and an implementation of a defrost cycle; 
         FIG.  10    is a schematic example of a cooling system of the refrigerator of  FIG.  1   ; 
         FIG.  11    is a graph representing an ice harvest cycle time when an ice making cycle and a defrost cycle are unsynchronized; 
         FIG.  12    is a graph representing an ice harvest cycle time when an ice making cycle and a defrost cycle are synchronized; and 
         FIG.  13    is a front perspective view of another embodiment of the refrigerator in  FIG.  1   , showing a plurality of alternative cooling options for an ice maker. 
     
    
    
     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  100 . Although the detailed description that follows concerns a domestic refrigerator  100 , the invention can be embodied by refrigeration appliances other than a domestic refrigerator  100 . Further, an embodiment is described in detail below and shown in the figures as a bottom-mount configuration of a refrigerator  100 , including a fresh food compartment  102  disposed vertically above a freezer compartment  104 . It is to be understood that other configurations are contemplated, for example, a top-mount refrigerator (i.e., fresh food compartment disposed vertically below the freezer compartment), a side by side refrigerator (i.e., fresh food compartment disposed laterally adjacent the freezer compartment), a single compartment refrigerator (i.e., having only a fresh food compartment or a freezer compartment), refrigerators including variable climate zone compartments, etc. 
     One or more doors  106  are pivotally coupled to a cabinet  108  of the refrigerator  100  to restrict and grant access to the fresh food compartment  102 . The door(s)  106  can include a single door that spans the entire lateral distance across the entrance to the fresh food compartment  102 , or can include a pair of French-type doors  106 , as shown in  FIG.  1   , that collectively span the entire lateral distance of the entrance to the fresh food compartment  102  to enclose the fresh food compartment  102 . 
     As shown in  FIG.  2   , a center flip mullion  110  is pivotally coupled to at least one of the doors  106  to establish a surface against which a seal provided to the other one of the doors  106  can seal the entrance to the fresh food compartment  102  at a location between opposing side surfaces  112  of the doors  106 . The center flip mullion  110  can be pivotally coupled to the door  106  to pivot between a first orientation that is substantially parallel to a planar surface of the door  106  when the door  106  is closed, and a different orientation when the door  106  is opened. The externally-exposed surface of the center flip mullion  110  is substantially parallel to the door  106  when the center flip mullion  110  is in the first orientation, and forms an angle other than parallel relative to the door  106  when the center flip mullion  110  is in the second orientation. The seal and the externally-exposed surface of the center flip mullion  110  cooperate approximately midway between the lateral sides of the fresh food compartment  102 . 
     Moving back to  FIG.  1   , the freezer compartment  104  is arranged vertically beneath the fresh food compartment  102 . A drawer assembly (not shown) including one or more freezer baskets (not shown) can be withdrawn from the freezer compartment  104  to grant a user access to food items stored in the freezer compartment  104 . The drawer assembly can be coupled to a freezer door  114  that includes a handle  116 . When a user grasps the handle  116  and pulls the freezer door  114  open, at least one or more of the freezer baskets is caused to be at least partially withdrawn from the freezer compartment  104 . 
     Referring to  FIG.  10   , an example cooling system  400  of the refrigerator  100  is schematically shown. The cooling system  400  includes conventional components, such as a freezer evaporator  402 , an accumulator  404  (optional), a compressor  406 , a condenser  408 , a dryer  410 , and a dedicated ice maker evaporator  145 , as discussed further below. These components are conventional components that are well known to those skilled in the art and will not be described in detail herein. 
     The freezer compartment  104  is used to freeze and/or maintain articles of food stored therein in a frozen condition. For this purpose, the freezer compartment  104  is in thermal communication with the freezer evaporator  402  that removes thermal energy from the freezer compartment  104  to maintain the temperature therein at a temperature of 0° C. or less during operation of the refrigerator  100 , 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. 
     Moving back to  FIG.  2   , the refrigerator  100  further includes an interior liner comprising a fresh food liner  118  and a freezer liner  120  which define the fresh food and freezer compartments  102 ,  104 , respectively. The fresh food compartment  102  is located in the upper portion of the refrigerator  100  in this example and serves to minimize spoiling of articles of food stored therein. The fresh food compartment  102  accomplishes this by maintaining the temperature in the fresh food compartment  102  at a cool temperature that is typically above 0° C., so as not to freeze the articles of food in the fresh food compartment  102 . 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  402  can also be blown into the fresh food compartment  102  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  102  independent of the freezer compartment  104 . According to an embodiment, the temperature in the fresh food compartment  102  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  102  within a reasonably close tolerance of a temperature between 0.25° C. and 4° C. 
     With respect to  FIG.  1   , a dispenser  122  is disposed at one of the doors  106  and is provided to dispense liquid (e.g., water) and/or ice pieces therefrom. As shown, the dispenser  122  is provided on an exterior of one of the doors  106  such that a user can acquire water and/or ice pieces without opening said door  106 . Alternatively, it is contemplated that the dispenser  122  can be positioned on an interior of one of the doors  106  or on an interior wall of the refrigerator  100  such that a user must first open said door  106  before interacting with the dispenser  122 . 
     In operation, when a user desires ice (e.g., ice pieces), the user interacts with an actuator (e.g., lever, switch, proximity sensor, etc.) to cause frozen ice pieces to be dispensed from an ice bin  124  ( FIG.  2   ) of an ice maker  126 . Ice pieces stored within the ice bin  124  can exit the ice bin  124  through an aperture  128  and be delivered to the dispenser  122  via an ice chute  130 . In the embodiment shown, the ice chute  130  extends at least partially through the door  106  between the dispenser  122  and the ice bin  124 . As further shown, the ice maker  126  is located within the fresh food compartment  102  and, more particularly, at an upper corner defined by the fresh food liner  118 . Alternatively, the ice maker  126  (and possibly the ice bin  124 ) can be mounted to an interior surface of the door  106 . It is further contemplated that the ice maker  126  and the ice bin  124  can be separate elements, in which one remains within the fresh food compartment  102  and the other resides on the door  106 . 
     In alternative embodiments (not shown), the ice maker  126  is located within the freezer compartment  104 . In this configuration, although still disposed within the freezer compartment  104 , at least the ice maker  126  (and possibly the ice bin  124 ) is mounted to an interior surface of the freezer door  114 . It is contemplated that the ice maker  126  and ice bin  124  can be separate elements, in which one remains within the freezer compartment  104  and the other is on the freezer door  114 . 
     Additionally, when a user desires water, the user interacts with the actuator to acquire water from the dispenser  122 . Generally, water is directed through a water circuit of the refrigerator  100  wherein it is pumped to the dispenser  122  from an external source (not shown). Typically, such water circuits include a series of water lines (e.g., conduits, tubes, etc.) to transport the water from the external source to the dispenser  122 . Filters and water storage tanks are often also employed to filter the water passing therethrough and to store the water (either filtered or unfiltered) for subsequent downstream use. 
     Moving on to  FIG.  3   , the ice maker  126  is shown as being disposed at an upper corner of the fresh food compartment  102 . Specifically, the ice maker  126  is located adjacent a rear wall  132 , top wall  134 , and side wall  136  of the fresh food liner  118 . Alternatively, the ice maker  126  can be positioned at other locations within the fresh food compartment  102 . For example, the ice maker  126  could be positioned at a lower corner of the fresh food compartment  102  (i.e., adjacent a horizontal mullion that separates the fresh food and freezer compartments  102 ,  104 ), on a storage shelf located within the fresh food compartment  102 , or even on/within one of the doors  106  that provides selective access to the fresh food compartment  102  (as further discussed below). 
     The ice maker  126  is shown as comprising an ice maker frame  138 , an ice bin  140 , and an air handler  142 . The air handler  142  is secured adjacent the rear wall  132  of the fresh food liner  118 , and both the ice maker frame  138  and the ice bin  140  extend outwards therefrom towards a front of the refrigerator  100 . Additionally, the ice maker frame  138  is disposed vertically above the ice bin  140  and houses an ice tray  144  therein. Due to this configuration, after the ice pieces have been formed, the ice pieces can then be transported to the ice bin  140  in an efficient manner. For example, the ice tray  144  may rotate about a horizontal axis until the ice pieces face the ice bin  140  and are subsequently ejected from the ice tray  144 . Further, the evaporator  145  is disposed within (i.e., positioned behind) the air handler  142 . The evaporator  145  is configured to cool water in the ice tray  144  to a temperature sufficient for ice piece production. 
     With respect to  FIG.  4   , the air handler  142  comprises a housing  148  that covers (i.e., houses) various components related to the functionality of ice making/dispensing. For example, the housing  148  can house an auger motor, a crush cube solenoid, a fan, EPS foam, electrical harnesses, etc. (not shown). Specifically, as depicted in  FIGS.  6 - 7   , a fan  149  is disposed upstream of a fan outlet diffuser  150  formed into the housing  148 . The fan outlet diffuser  150  may be formed integral with the housing  148  during a simulations manufacturing process. Alternatively, the fan outlet diffuser  150  may be separate and distinct from the housing  148  such that the fan outlet diffuser  150  is manufactured individually with respect to the housing  148  and subsequently fixed thereto via known methods. Moreover, the fan  149  may be an axial fan, a radial fan, or any other type of fan generally known in the art. 
     As shown in  FIG.  4   , the fan outlet diffuser  150  is substantially circular in shape and includes a first wall  153  that defines a central body  155  of the fan outlet diffuser  150 . Specifically, the first wall  153  is cylindrical in shape and extends axially along an axis “X.” As such, the central body  155  is provided at a radial center of the fan outlet diffuser  150 . In one embodiment, the central body  155  can have a closed wall at an end face and/or be solid. In another embodiment, the central body  155  can comprise an aperture extending therethrough. The first wall  153  is peripherally surrounded by a second wall  157 . That is, the second wall  157  is radially spaced apart from the first wall  153 . Moreover, the second wall  157  is shown as being substantially cylindrical in shape, wherein the first wall  153  and the second wall  157  of the fan outlet diffuser  150  are coaxial. A plurality of radially extending fins  151  are disposed circumferentially about the first wall  153  of the fan outlet diffuser  150 . Specifically, the plurality of radially extending fins  151  are disposed between the first wall  153  and the second wall  157 , wherein each of the plurality of radially extending fins  151  is spaced apart, one from the other, along an outer peripheral surface of the first wall  153 . Alternatively, the fan outlet diffuser  150  can have a different shape (e.g., oval, rectangle, square, triangle, etc.). Optionally, one or more radially extending auxiliary fins can be attached to and disposed circumferentially about one of the first wall  153  or second wall  157 , and such auxiliary fins can extend only partially between the first and second walls  153 ,  157 . Further still, an optional third wall  167  can be disposed radially intermediate the first wall  153  and the second wall  157  such that the third wall  167  is coaxial with the first wall  153  and/or the second wall  157 . 
     Moving on to  FIG.  5   , the ice maker frame  138  includes an air inlet  152  formed at a rear end  154  thereof. The air inlet  152  comprises a first wall  159  having a cylindrical shape and extending along an axis “Y.” The first wall  159  of the air inlet  152  is peripherally surrounded by a second wall  161 . That is, the second wall  161  of the air inlet  152  is radially spaced apart from the first wall  159  of the air inlet  152 , such that the first and second walls  159 ,  161  are coaxial with one another. At least one projection rib  163  extends between the first and second walls  159 ,  161  of the air inlet  152 , and more particularly, the at least one projection rib  163  extends from the first wall  159  to the second wall  161  of the air inlet  152 . The projection rib(s)  163  provides structural rigidity to the air inlet  152  in a manner that does not substantially impede airflow to the ice tray  144 , as will be detailed below. 
     As further shown, the first wall  159  of the air inlet  152  peripherally surrounds a cylindrical connection member  158 . The cylindrical connection member  158  is configured to receive a pin  165  of the ice tray  144  in order to rotatably support the ice tray  144 . Specifically, the ice tray  144  extends from the rear end  154  of the ice maker frame  138  towards a front end  156  of the ice maker frame  138  and is rotatably secured thereto via the cylindrical connection member  158 . The cylindrical connection member  158  is disposed at a radial center of the air inlet  152  (i.e., the radial center point of the pin  165  lies on the axis Y). The configuration of the air inlet  152  substantially mirrors that of the fan outlet diffuser  150 , discussed above. That is, as will be detailed below, the radial center point of the fan outlet diffuser  150  and that of the air inlet  152  are configured to lie on the same axis. 
     In an installed position, the air inlet  152  of the ice maker frame  138  circumferentially surrounds the fan outlet diffuser  150 . That is, as shown in  FIGS.  6 - 7   , the second wall  161  of the air inlet  152  peripherally surrounds the second wall  157  of the fan outlet diffuser  150 . Moreover, the first wall  153  of the fan outlet diffuser  150  is disposed directly adjacent the first wall  159  of the air inlet  152  such that the former and the latter are coaxial with one another (i.e., a radial center point of the first wall  153  of the fan outlet diffuser  150  and that of the first wall  159  of the air inlet  152  lie on a common axis). As such, the fan  149  is positioned relatively close (i.e., adjacent) to the air inlet  152 , without any significant obstacles positioned therebetween. In this manner, the air inlet  152  remains substantially unimpeded from obstacles that would otherwise obstruct the air flowing from the air handler  142  to the ice tray  144 . This configuration may reduce the number of obstacles between the air handler  142  and the ice tray  144  (as compared to conventional assemblies) so that the fan  149  can direct an airflow out of the outlet diffuser  150  and into the air inlet  152  in an efficient manner, as will be further detailed below. 
     With respect to  FIG.  7   , the fan  149  directs an airflow “F” from within the housing  148  of the air handler  142  towards the air inlet  152  of the ice maker frame  138 . As shown, a blade of the fan  149  has a directing surface (i.e., a surface configured to drive the airflow F) which decreases (as detailed by a dotted line “A”) with respect an imaginary horizontal plane. Further, the radially extending fins  151  have a guiding surface (i.e., a surface configured to guide the airflow F) which increases (as detailed by a dotted line “B”) with respect to an imaginary horizontal plane. In other words, the radially extending fins  151  are pitched opposite to the blades of the fan  149 . Due to this configuration, the radially extending fins  151  counteract the swirling effect caused by the pitch of the blades such that the airflow F is directed into the ice maker frame  138  in a generally linear manner. It is to be understood that the directing surface of the blades of the fan  149  and the guiding surface of the radially extending fins  151  need not decrease and increase, respectively, with respect to an imaginary horizontal plane. The above-noted surfaces may have any configuration, so long as the pitch of the blades of the fan  149  and the pitch of the radially extending fins  151  are opposite to one another. 
     Accordingly, due to the geometric configuration of the radially extending fins  151 , the airflow F is efficiently directed into the ice maker frame  138  in such a way that the airflow F interacts and cools the entire ice tray  144 . That is, the radially extending fins  151  prevent the airflow F from rebounding back into the air handler  142  and/or not interacting/cooling the entire ice tray  144 . As such, the cold air from the housing  148  may flow efficiently to the ice tray  144  so that the time it takes for the water within the ice tray  144  to freeze is reduced. 
     With reference to  FIGS.  8 - 9   , methods of forming ice pieces and operating the ice maker  126  will now be discussed. Specifically,  FIG.  8    depicts a flow chart of an ice making cycle  200  of the aforementioned ice maker  126 . In an initial step, a filling phase  202  is initiated wherein water, directed from an upstream source, enters the ice tray  144 . The water may be transported from an external water source or a source located within the refrigerator  100  (e.g., a water storage tank). Further, the commencement of the filling phase  202  may occur in various ways. For example, the ice maker  126  may include a sensor (e.g., a capacitance sensor) to sense an overall weight of the ice pieces within the ice bin  140  and compare the sensed weight to a predetermined weight indicative of various fill levels of ice pieces (e.g., full, half full, etc.) within the ice bin  140 . Alternatively, other sensors may be used to determine a height of the ice pieces within the ice bin  140  to determine whether the ice bin  140  is full. Further still, the filling phase  202  may begin by user request. 
     Moreover, although not shown, the ice maker  126  may include sensors configured to determine when cavities in the ice tray  144  are filled with water. For example, the sensors may sense when the ice tray  144  is filled and send a signal to a controller  203  (shown schematically in  FIG.  1   ) to stop supplying water to the ice maker  126 . Subsequently, after the filling phase  202  of the ice making cycle  200  is completed, a freezing phase  204  begins. Specifically, during the freezing phase  204 , a temperature of the water within the ice tray  144  is reduced. This is accomplished by the evaporator  145  (disposed within the air handler  142 ) lowering the temperature within the ice maker  126  to permit a phase change of the water within the ice tray  144 . That is, the air within the ice maker  126  is cooled to a temperature that promotes the liquid water to freeze into solid ice pieces. 
     After the freezing phase  204  has concluded (i.e., the water within the ice tray  144  has frozen into ice pieces), a harvesting phase  206  may begin. As briefly noted above, the function of the harvesting phase  206  is directed towards disengaging the ice pieces from the ice tray  144  and transferring the ice pieces to the ice bin  140 . Before the harvesting phase  206  begins, several criteria must first be met. Specifically, a sensed temperature must be below a maximum harvest temperature and a minimum freeze time must be met. 
     The maximum harvest temperature is the maximum temperature of the ice pieces in the ice tray, as detected by a sensor (e.g., a thermistor), at which harvesting can occur. In one embodiment (see  FIG.  3   ), the temperature sensor (not shown) may be positioned on a bottom of the ice tray  144 . Specifically, the temperature sensor may be inserted into a reception area formed into the ice tray  144  or, alternatively, be disposed adjacent a bottom thereof. Further, insulation (e.g., foam block insulation  207 , as depicted in  FIG.  3   ) is generally provided about the sensor (e.g., surrounding the sensor) so as to thermally isolate the temperature sensor from air within the ice maker  126 . In this manner, the temperature sensor is capable of providing an accurate reading of the temperature of the water/ice within the ice tray  144 , which is uninfluenced by the temperature of the air within the ice maker  126 . 
     During operation, the temperature sensed by the sensor must be below (i.e., colder) the maximum harvest temperature. The minimum freeze time is directed toward a minimum amount of time between the completion of the filling phase  202  and the initiation of the harvesting phase  206 . That is, the minimum freeze time is a pre-set time period which must occur before the harvesting phase  206  initiates. Of note, the sensed temperature being below the maximum harvest temperature can be achieved before the minimum freeze time is reached, and vise-versa; however, the harvest phase  206  will not begin until both of the foregoing conditions are met. 
     As mentioned above, after the harvesting phase  206  begins, the ice pieces are ejected from the ice tray  144  and stored in the ice bin  140 . Thereafter, the ice making cycle  200  may continue its operation by initiating the filling phase  202  once more. The ice making cycle  200  may be in constant operation until it is determined that the ice bin  140  has been filled with ice pieces. Alternatively, a predetermined time period may occur between each ice making cycle  200 . 
     Over time, due to the cold environments associated with the overall refrigerator  100  and the ice maker  126 , a layer of frost often builds up on evaporators associated therewith. This can occur with an evaporator associated with the main cooling system of the refrigerator (i.e., a system evaporator which maintains the fresh food and/or freezer compartment  102 ,  104  at an appropriate operating temperature), or an evaporator dedicated to the ice maker  126 , such as the evaporator  145  positioned within the air handler  142 . The following disclosure is directed towards defrosting various elements associated with the ice maker  126  (e.g., the evaporator  145  within the air handler  142 ), however, it is to be understood that the disclosure is likewise applicable to any other element employed by the refrigerator  100 . 
     To remove the build-up of frost formed on the evaporator  145 , a defrost heater  208  is employed in the refrigerator  100 . As schematically shown in  FIG.  3   , the defrost heater  208  may be positioned within the air handler  142 . However, it is contemplated that the defrost heater  208  may be positioned outside the air handler  142 , but directly adjacent the ice maker  126 , or at any other location within the refrigerator  100 . Specifically, the defrost heater  208  may be a resistive heating element that contacts or is in close proximity to the evaporator  145 . However, it is contemplated that the defrost heater  208  can be of a different configuration known in the art. The defrost heater  208  is configured to heat the one or more evaporators (e.g., evaporator  145 ) of the refrigerator  100 . In doing so, the increase in temperature eliminates (i.e., melts) the frost on the one or more evaporators. To ensure that this frost is continuously eliminated, the controller  203  includes an algorithm that employs a defrost cycle that operates the defrost heater  208  a predetermined number of times over a predetermined time period. 
     Specifically, the present method synchronizes the implementation of the ice making cycle  200  of the ice maker  126  and the implementation of the defrost cycle associated with the one or more evaporators (e.g., evaporator  145 ) to hinder interruption of the ice making cycle  200 . In this manner, neither the ice making cycle  200  of the ice maker  126  nor the defrost cycle associated with the one or more evaporators (e.g., evaporator  145 ) has priority over the other. 
     With respect to  FIG.  9   , this synchronization is accomplished via the algorithm employed by the controller  203 . Specifically, the algorithm begins with a first step  301  of calculating a time until an upcoming defrost cycle is scheduled to occur. Of note, this and the below reference of “time” may be based on a real time clock used by the controller  203  of the refrigerator  100 . For example, during installation of the refrigerator  100  the real time clock may be programmed with the actual time of day. Alternatively, the “time” may be tracked or determined via a counting device that determines and/or outputs how much time (e.g., seconds, minutes, hours, etc.) has elapsed. The timer may be initiated based on the occurrence of a predetermined event. Further still, it is contemplated that the “time” may be generated by other known methods/techniques known in the art. 
     Subsequently, a second step  302  determines whether the calculated time (from the first step  301 ) is less than or equal to a predetermined time period. For example,  FIG.  9    depicts that this predetermined time period is 30 minutes. However, it is contemplated that other time periods (e.g., greater than or less than 30 minutes) may be used. If the calculated time is greater than 30 minutes, then the algorithm reverts back to the first step  301 . Alternatively, if the calculated time is less than or equal to the predetermined time period (i.e., 30 minutes), then a third step  303  occurs where an inquiry is made as to whether the upcoming defrost cycle will begin during an ice making cycle  200 . That is, the third step  303  determines whether the ice maker  126  will be in any one of the filling phase  202 , the freezing phase  204 , and the harvesting phase  206  when the upcoming defrost cycle is scheduled to begin. 
     If the upcoming defrost cycle is not scheduled to begin during an ice making cycle  200 , then operation of the upcoming defrost cycle will begin at its originally scheduled time, as shown in a fourth step  304 . Of note, after the determination has been made that the upcoming defrost cycle is not scheduled to begin during an ice making cycle  200 , the algorithm may begin once more at the first step  301 . In this manner, it is ensured that the upcoming defrost cycle will not overlap or simultaneously run with an ice making cycle  200 . 
     Alternatively, if the upcoming defrost cycle is scheduled to begin during an ice making cycle  200 , then an inquiry is made to determine at what point in time during the operation of the ice making cycle  200  the upcoming defrost cycle is scheduled to begin. Specifically, in a fifth step  305 , an inquiry is made as to whether a predetermined time period, from the start of the ice making cycle  200 , will have elapsed when the upcoming defrost cycle is scheduled to begin. This predetermined time period can be equivalent to half of the overall time period it takes for the ice making cycle  200  to complete operation. That is, if the ice making cycle  200  operates for a time period of 60 minutes, then the predetermined time period may be 30 minutes. Alternatively, the predetermined time period may be any other amount of time. 
     With respect to the above-example, if the upcoming defrost cycle is scheduled to begin after 30 minutes from the start of the ice making cycle  200  (i.e., within the second half of the ice making cycle  200 ), then the controller  203  reschedules the upcoming defrost cycle to begin operation after the ice making cycle  200  has completed, as shown in a sixth step  306 . That is, the upcoming defrost cycle will not begin at its originally scheduled time period. Rather, the upcoming defrost cycle will begin at a later time period, after the ice making cycle  200  has completed. Of note, the controller  203  can reschedule the upcoming defrost cycle to begin immediately after the ice making cycle  200  has completed, or at a predetermined time period after the ice making cycle  200  has completed. 
     Alternatively, with respect to the fifth step  305 , if the upcoming defrost cycle is scheduled to begin within 30 minutes from the start of the ice making cycle  200  (i.e., within the first half of the ice making cycle  200 ), then an inquiry is made, as shown in a seventh step  307 , as to whether a minimum compressor run-time has elapsed since the completion of a previous defrost cycle. The minimum compressor run-time may be, for example, eight hours, and is generally indicative of an industrial requirement for a minimum amount of time the compressor  406  must be operational between consecutive defrost cycles. It is to be understood that the above-noted minimum compressor run-time need not be eight hours, and that any other predetermined amount of time may be used. 
     If the minimum compressor run-time has not elapsed (i.e., the compressor has been operational for less than eight hours since the completion of the previous defrost cycle), then the controller  203  reschedules the upcoming defrost cycle to begin operation after the ice making cycle  200  has completed, as shown in the sixth step  306 . After the sixth step  306 , the algorithm may once again revert back to the first step  301 . 
     Alternatively, if the minimum compressor run-time has elapsed (i.e., the compressor has been operational for greater than or equal to eight hours since the completion of the previous defrost cycle), then the controller  203  reschedules the upcoming defrost cycle to begin operation immediately, as shown in an eighth step  308 . In other words, the controller  203  will immediately initiate operation of the upcoming defrost cycle, as opposed to waiting until the upcoming defrost cycle&#39;s originally scheduled start time. Of note, after the upcoming defrost cycle has be rescheduled to begin immediately, and after said defrost cycle has been completed, the algorithm may once again revert back to the first step  301 . 
     While not shown, the algorithm will only delay the upcoming defrost cycle for a predetermined maximum period of time. It is contemplated that this predetermined maximum period of time is selected such that in the case of a fault (e.g., a hardware failure), the controller  203  does not continue to wait for an abnormally long period of time. This predetermined maximum period of time is preferably 90 minutes, and even more preferably 60 minutes; however, it is contemplated that the predetermined maximum period of time may be any other amount of time. For example, after the sixth step  306 , the controller  203  may initiate a timer. If the timer reaches the predetermined maximum period of time, and the upcoming defrost cycle has not yet begun, then the controller  203  will immediately cancel operation of the present ice making cycle  200  and begin operation of the upcoming defrost cycle, if the predetermined time period in the seventh step  307  has elapsed (i.e., the predetermined time period since the completion of the previous defrost cycle). 
     As described in detail above, the defrost cycle only occurs when the ice making cycle  200  is not in operation. The implementation of the defrost cycle is either advanced in time or delayed such that the defrost cycle does not overlap with the ice making cycle  200 . Accordingly, the aforementioned algorithm synchronizes the implementation of the ice making cycle  200  of the ice maker  126  with the implementation of the defrost cycle of the evaporator  145  so that operation of the ice making cycle  200  is not interrupted. 
     Accordingly, the aforementioned ice maker  126  configuration and algorithm may increase the overall efficiency of the refrigerator  100 . In particular, by preventing the defrost cycle from overlapping the ice making cycle  200 , the present configuration and algorithm may reduce the occurrence of unnecessary cooling of the ice tray  144 . This elimination in overlap may allow the ice maker to freeze ice in less time and, thereby, increase the daily ice production rate, as compared to conventional ice makers. For example, the daily ice production rate may increase from 2.7-3.0 lbs. of ice per day, for a conventional ice maker, to 3.3-3.5 lbs. of ice per day for the ice maker configuration and algorithm described herein. 
     For example, with respect to  FIG.  11   , a graph of an ice harvest cycle time is shown wherein the ice making cycle and the defrost cycle are unsynchronized. Specifically, the graph is shown with the temperature (° C.) of the ice maker tray  144  represented on the left-hand Y-axis and time represented on the X-axis. Further, the harvest time (in minutes) associated with a timer (i.e., a harvest timer) is represented on the right-hand Y-axis for use with the dot-dash line on the graph. In the cycle illustrated, a first defrost cycle A 1  is initiated while an ice making cycle is operating. More particularly, the first defrost cycle A 1  is initiated while an initial harvest timer B 1  is counting down. Because of the first defrost cycle A 1 , the controller (e.g., controller  203 ) stores the time remaining for the initial harvest timer B 1  and assigns it to a subsequent harvest timer Cl that is initiated after the completion of the first defrost cycle A 1 . 
     As illustrated in  FIG.  11   , the temperature of the ice tray  144  increases during the first defrost cycle A 1 . Once the first defrost cycle A 1  is completed, the controller (e.g., controller  203 ) returns to the ice making cycle and initiates the subsequent harvest timer Cl. During the subsequent harvest timer Cl, the temperature of the ice tray  144  achieves a sub-cooling effect D 1  (i.e., a temperature of the ice tray  144  substantially surpasses the maximum harvest temperature) which results in an increase in the ice making cycle times as well as requiring higher energy demands. 
       FIG.  11    also illustrates a second defrost cycle A 2  that is initiated while an ice making cycle is operating. Specifically, the second defrost cycle A 2  is initiated after a harvest timer B 2  has expired, but before the sensed temperature falls below the maximum harvest temperature. After the completion of the second defrost cycle A 2 , the controller  203  returns to the ice making cycle such that cooling air is again conveyed over the ice maker  126  until the sensed temperature falls below the maximum harvest temperature. This excess cooling causes the ice maker  126  to cool to well below the maximum harvest temperature (i.e., a sub-cooling effect D 2 ). Again, this results in an increase in ice making cycle times as well as higher energy demands. 
     In contrast, with respect to  FIG.  12   , a graph of an ice harvest cycle time is shown wherein the ice making cycle and the defrost cycle are synchronized. Again, the graph is shown with the temperature (° C.) of the ice maker tray  144  represented on the left-hand Y-axis and time represented on the X-axis. Further, the harvest time (in minutes) associated with a timer (i.e., a harvest timer) is represented on the right-hand Y-axis for use with the dot-dash line on the graph. The defrost cycle A 3  begins at substantially the same time as the harvest timer B 3 . Although defrost cycle A 3  may cause the temperature of the ice maker  126  to increase, the system is able to quickly cool the ice maker  126  after the completion of the defrost cycle A 3 . The time required to recover from the defrost cycle A 3  is short and does not appreciably extend the ice maker cycle. Further, as illustrated in  FIG.  12   , the sensed temperature of the ice maker  126  does not decrease significantly below the target ice harvest temperature, (i.e., there is no super-cooling effect as illustrated in  FIG.  11   ). Accordingly, no subsequent harvest timer is required, and a sub-cooling effect does not occur. 
     As briefly mentioned above, the ice maker  126  of the present application may be mounted on the freezer door  114  (shown in  FIG.  1   ). Cold air can be ducted to the freezer door  114  from an evaporator in the fresh food compartment  102  or the freezer compartment (e.g., freezer evaporator  402 ), including the system evaporator. The cold air can be ducted in various configurations, such as ducts that extend on or in the freezer door  114 , or possibly ducts that are positioned on or in side walls of the freezer liner  120  or a top wall of the freezer liner  120 . In one example, a cold air duct can extend across the top wall of the freezer compartment  104 , and can have an end adjacent to the ice maker  126  (when the freezer door is in the closed condition) that discharges cold air over and across the ice mold. If an ice bin (e.g., ice bin  124 ) is also located on the interior of the freezer door  114 , the cold air can flow downwards across the ice bin  124  to maintain the ice pieces at a frozen state. The cold air can then be returned to the freezer compartment  104  via a duct extending back to the freezer evaporator  402 . The ice tray  144  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  402  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 tray  144 . Of course, it is contemplated that the ice maker  126  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  126  of the instant application could be used in the fresh food compartment  102 , either within the interior of the cabinet  108  or on the door  106  of the fresh food compartment  102 . Moving now to  FIG.  13   , another embodiment of the refrigerator  100  is shown, wherein a plurality of alternative cooling options are depicted for supplying cold air to the ice maker  126  disposed on the door  106  of the fresh food compartment  102 . In one example, cold air can be transported to the ice maker  126  from the dedicated ice maker evaporator  145  disposed adjacent the fresh food liner  118  (as discussed above). The cold air can be transported via a ducting system that extends from a first end A 1  to a second end A 2 . For example, as shown, the first end A 1  can be disposed on the fresh food liner  118  at the rear wall  132 , and may be routed along the rear wall  132 , top wall  134 , and/or side wall  136 , to the second end A 2  disposed at the ice maker  126  on the door  106 . Of note, the ducting system can include at least one gasket to create a seal when the door  106  is in the closed position. As the cold air enters the ice maker  126 , the cold air discharges over and across the ice tray  144  (not shown). 
     In another example, cold air can be transported to the ice maker  126  from the dedicated freezer evaporator  402  located in the freezer compartment  104 . Similar to the example above, the cold air can be transported via a ducting system that extends from a first end B 1  to a second end B 2 . For example, as shown, the first end B 1  can be disposed on the freezer liner  120  (i.e., at a rear wall thereof), and may extend along its walls as well as the walls of the fresh food liner  118  to reach the second end B 2  disposed at the ice maker  126  on the door  106 . Again, the ducting system can include at least one gasket to create a seal when the door  106  is in the closed position. 
     In a further example, the ice maker  126  can itself include an ice maker evaporator C, similar to the ice maker evaporator  145  discussed above. That is, the ice maker evaporator C is an evaporator connected to the system evaporator of the refrigerator  100  and is located within the ice maker  126  for the purpose of discharging cold air over and across the ice tray  144  (not shown). In yet another example, the ice maker  126  can itself include an ice maker evaporator D, that is completely separate and distinct from the system evaporator of the refrigerator  100 . That is, the ice maker evaporator D is an independent refrigeration system located within the ice maker  126  and is configured to discharge cold air over and across the ice tray  144  (not shown). 
     It is further contemplated that although cold air ducting from the freezer evaporator  402  (or similarly a fresh food evaporator, e.g. the ice maker evaporator  145 ) 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 tray  144 . Of course, it is contemplated that the ice maker  126  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. Example 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.