Icemaker for a refrigerator

An icemaker having a mold comprising at least one cavity and a cooling system. The cooling system has a first heat exchanger configured to have a medium flow there through. The first heat exchanger is in thermal communication with the mold to reduce the temperature of the mold below a predetermined temperature.

BACKGROUND OF THE INVENTION

This invention relates generally to icemakers, and more particularly, to an icemaker utilizing a secondary loop cooling circuit in a refrigerator.

In a known refrigerator, an icemaker delivers ice through an opening in a door of the refrigerator. Such a known refrigerator has a freezer section to the side of a fresh food section. This type of refrigerator is often referred to as a “side-by-side” refrigerator. In the side-by-side refrigerator, the icemaker delivers ice through the door of the freezer section. In this arrangement, ice is formed by freezing water with cold air in the freezer section, the air being made cold by a cooling system that includes an evaporator.

Another known refrigerator includes a bottom freezer section disposed below a top fresh food section. This type of refrigerator is often referred to as a “bottom freezer” or “bottom mount freezer” refrigerator. In this arrangement, convenience necessitates that the icemaker deliver ice through the opening in the door of the fresh food section, rather than the freezer section. However, the cool air in the fresh food section is generally not cold enough to freeze water to form ice.

In the bottom freezer refrigerator, it is known to pump cold air, which is cooled by the evaporator of the cooling system, within an interior channel of the door of the fresh food section to the icemaker. This arrangement suffers from numerous disadvantages. For example, complicated air ducts are required within the interior of the door for the cold air to flow to the icemaker. Further, ice is made at a relatively slow rate, due to limitations on volume and/or temperature of cold air that can be pumped within the interior of the door of the fresh food section. Another disadvantage is that pumping the cold air to the fresh food compartment during ice production reduces the temperature of the fresh food compartment below the set point.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, an icemaker having a mold with at least one cavity and a cooling system. The cooling system has a first heat exchanger configured to have a medium flow there through. The first heat exchanger is in thermal communication with the mold to reduce the temperature of the mold below a predetermined temperature.

In another aspect of the invention, a refrigerator has an icemaker comprising a mold with at least one cavity and a cooling system. The cooling system has a first heat exchanger configured to have a medium flow there through. The first heat exchanger is in thermal communication with the mold to reduce the temperature of the mold below a predetermined temperature.

DETAILED DESCRIPTION OF THE INVENTION

It is contemplated that the teaching of the description set forth below is applicable to all types of refrigeration appliances, including but not limited to side-by-side and top mount refrigerators wherein undesirable temperature gradients exist within the compartments. The present invention is therefore not intended to be limited to any particular type or configuration of a refrigerator, such as refrigerator100.

FIGS. 1 and 2illustrate a side-by-side refrigerator100including a fresh food compartment102and freezer compartment104. Freezer compartment104and fresh food compartment102are arranged in a bottom mount configuration where the freezer compartment104is below the fresh food compartment102. The fresh food compartment is shown with French opening doors134and135. However, a single door may be used. Door or drawer132closes freezer compartment104.

The fresh food compartment102and freezer compartment104are contained within an outer case106. Outer case106normally is formed by folding a sheet of a suitable material, such as pre-painted steel, into an inverted U-shape to form top and sidewalls230,232of case106. Mullion114is preferably formed of an extruded ABS material. Mullion114separates the fresh food compartment102and the freezer compartment104.

Door132and doors134,135close access openings to freezer and fresh food compartments104,102, respectively. Each door134and135is mounted by a top hinge136and a bottom hinge137to rotate about its outer vertically oriented edge between an open position, as shown inFIG. 2, and a closed position shown inFIG. 1closing the associated storage compartment.

In accordance with known refrigerators, refrigerator100also includes a machinery compartment (not shown) that at least partially contains components for executing a known vapor compression cycle for cooling air in the compartments. The components include a compressor (not shown), a condenser (not shown), an expansion device (not shown), and an evaporator (not shown) connected in series and charged with a refrigerant. The evaporator is a type of heat exchanger that transfers heat from air passing over the evaporator to a refrigerant flowing through the evaporator, thereby causing the refrigerant to vaporize. The cooled air is used to refrigerate one or more fresh food or freezer compartments via fans (not shown). Collectively, the vapor compression cycle components in a refrigeration circuit, associated fans, and associated compartments are referred to herein as a sealed system. The construction of the sealed system is well known and therefore not described in detail herein, and the sealed system is operable to force cold air through the refrigerator100.

The icemaker200is configured to produce ice, and to provide the produced ice through an opening in a door of the fresh food compartment102. It is contemplated that the icemaker200can be used with a bottom freezer refrigerator, in which the bottom freezer compartment is disposed below a top fresh food compartment. It is understood, however, that the icemaker200is not limited to use in the bottom freezer refrigerator. For example, the icemaker200can be configured to produce ice and to provide the produced ice through an opening in a door of a fresh food compartment of a side-by-side refrigerator in which the freezer compartment is disposed to the side of the fresh food compartment. Alternately, the icemaker200can be disposed in various refrigerators in which the fresh food and freezer compartments are disposed in a variety of positions relative to one another. It is further understood that the refrigerator in which the icemaker200is disposed is not required to have one or only one of each of the fresh food and freezer compartments, but rather can include none, or one or more of each of the fresh food and freezer compartments. By way of non-limiting examples, the icemaker200can be disposed in the refrigerator that includes one or more fresh food compartments and no freezer compartment, or that includes one or more freezer compartments and no fresh food compartment.

The icemaker200is provided in addition to the freezer compartment cooling system210, and produces and provides ice separate from operation of the freezer compartment cooling system210. By this arrangement, disadvantages associated with a known icemaker, particularly in a bottom freezer refrigerator, are overcome. Specifically, in embodiments of the invention, ice is produced at a faster rate because ice production is not dependent on a volume or temperature of cold air that can be pumped within a channel interior of the door of the fresh food compartment.

FIG. 4shows an exemplary secondary loop cooling system for use with icemaker200. The secondary loop cooling system includes a medium storage tank206configured to hold a medium such as a propylene glycol and water mixture. Tank206is flow connected outlet line220and inlet line222. Outlet line220enters the heat exchanger344of ice-forming device340. The heat exchanger of the ice-forming device is flow connected with the heat exchanger360of the ice receptacle350.

A pump230is configured to pump the medium within the lines220222between the heat exchangers344,360and the medium storage tank206. Typically, the pump will move the medium from the medium storage tank206in line220to the icemaker200and back to the storage tank in line222. The pump230may be placed in any effective location to accomplish the movement of the medium. In the storage tank206the medium is cooled through heat transfer to a predetermined temperature. This temperature is preferably below the standard freezing point of water. As shown, a closed loop212of the freezer compartment cooling system210may be used to cool the medium in storage tank206. However, the storage tank206may be configured also to transfer heat to the freezer compartment, which is then cooled by the primary loop of the freezer compartment cooling system210.

As shown inFIG. 5, the cooled medium flows through an ice-forming device340configured to freeze water to produce ice. The ice-forming device340includes an ice mold341. The ice mold341includes one or more cavities342configured to receive water from an outside water source (e.g., from a water line), and to retain the water during freezing.

The ice forming device340also includes a heat exchanger portion344disposed adjacent (e.g., near or as a portion of) the cavities342of the ice mold341. It is contemplated that in embodiments of the invention, the heat exchanger344has one or more channels formed, cast, molded or otherwise provided in a bottom of the ice mold341and/or the ice-forming device340.

As shown, the heat exchanger portion344is formed by incorporating a cavity having a flat bottom, not shown in detail, in the base348of the ice mold341and closing the cavity with a cover345. The cover345, in combination with alternating ribs346, forms channels to direct the flow of the medium through the heat exchanger344. It is contemplated that the ribs may be formed in the cavity of the base348and the cover345may be flat or both the cavity and the cover may contain ribs. An o-ring gasket368or other similar sealing means is used to prevent leaking of the medium during operation. It is contemplated that cover345maybe brazed or welded or molded together with ice mold341.

By this arrangement, the cooled medium enters the ice-forming device340at port322. The cooled medium flows through the heat exchanger344absorbing heat from the mass of ice forming device340. After moving past the ribs346the medium flows into channel324through opening323. Channel324directs the medium to exit port321after flowing though heat exchanger344. Line220is flow connected to heat exchanger344at port321.

The water retained in the cavities342is cooled by the reduced temperature of the mass of ice-forming device340to a temperature equal to or less than the standard freezing point temperature of water. As a result, the water retained in the cavities342of the ice mold341freezes, producing ice cubes.

In an alternate embodiment, the ice-forming device340may be made hollow with thin-formed exterior walls, not shown. In this alternate embodiment, the volume of medium present within ice forming device340acts as the mass for removing heat from water in the cavities342.

After the ice is formed it may be harvested in any conventional manner. For the ice-forming device340, a rack style harvester, not shown, is most common. The rack type harvester then utilizes rotating fingers to scoop the ice cubes out of the cavities342. Those of ordinary skill in the art know features of a rack harvester, and therefore further explanation is not required to provide a complete written description of embodiments of the invention or to enable those of ordinary skill in the art to make and use embodiments of the invention, and is not provided. Once harvested the ice cubes are stored in an ice receptacle350.

During harvesting the temperature of the cavities342is raised above the freezing point of water. This rise in temperature melts a thin layer of the ice cube releasing the ice cube from the cavity342. As shown inFIG. 6, to raise the temperature a cal rod heater380is wrapped around the exterior of or incorporated into the sides of ice mold341. Alternatively, an electric resistance wire heater may be molded into the ice mold341to facilitate the rise in temperature.

An ice delivery system is formed by the ice receptacle350ofFIG. 3, which is configured to receive the ice cubes from the ice-forming device340either directly or through a channel or funnel, and to retain the ice cubes therein. Details of an ice delivery system configured to deliver ice cubes from the ice forming device340to the ice receptacle350, whether separate from or as a component of the ice forming device340and/or the ice receptacle350, are also known, and are therefore neither required nor provided.

In embodiments of the invention, shown schematically inFIG. 4, a heat exchanger360is disposed adjacent an ice receptacle350with the medium flowing through the heat exchanger360subsequent to flowing through the heat exchanger344of the ice forming device340. Thus, the medium used during the production of ice is further warmed, absorbing heat from a volume adjacent the ice receptacle350. As a result, melting of ice retained within the ice receptacle350is impeded or prevented.

In embodiments of the invention, it is contemplated that the temperature of the warmed medium flowing through the heat exchanger360is still less than the standard freezing point temperature of water, such that melting of ice in the ice receptacle350is prevented. It is to be understood, however, that the heat exchanger360is not required in the icemaker200, and that in alternate embodiments the melting of ice retained within the ice receptacle350is impeded or prevented without the use of the heat exchanger360. In such alternate embodiments, the ice receptacle350is disposed adjacent the ice forming device340and/or the heat exchanger344. As a result, ice in the ice receptacle is prevented from melting as a result of cooling by the heat exchanger344. For example, when the ice receptacle350is disposed below the ice forming device340and the heat exchanger344, cold air flows from the heat exchanger344to the ice receptacle350as a result of natural convention.

After the warmed medium exits icemaker200the medium flows back to the medium storage tank206. Continued operation of the icemaker200is provided by repetition of the above-described flow of the medium from the medium storage tank206through tubing220to heat exchangers344and360, among the other components of the icemaker200, and back to storage tank206in tubing222.

Still further, details of an ice delivery system configured to deliver ice from the ice receptacle350through the opening in the door of the fresh food compartment102are known and thus not discussed.

The above-described medium path is for illustration purposes only. Specifically, refrigerant flows through the closed loop212of the freezer compartment cooling system210, while the medium flows through the storage tank206. In an alternate embodiment, a refrigeration coil for the fresh food compartment may be used. In yet another embodiment, the storage tank206may have heat removed by the convection of air in the freezer compartment.

In embodiments of the invention, the refrigerant of the closed loop212has an evaporation temperature of less than about 0 degrees Celsius. Further, in embodiments of the invention, the medium is propylene glycol and water, commonly referred to as “anti-freeze,” and is cooled in the storage tank206to a temperature well below the standard freezing point temperature of water.

In embodiments of the invention shown in the drawings, the storage tank206and the heat exchangers344and360are disposed downstream from one another, respectively, without intervening heat exchangers disposed there between. It is understood, however, that this efficient arrangement is not required, and other intervening heat exchangers may be included. Further, the heat exchanger360is not required to be disposed downstream of the heat exchanger344, and the heat exchanger360can be disposed upstream of the heat exchanger344. Similarly, the storage tank206and/or the pump230can be disposed at various locations within the refrigerator100, and therefore the depicted and described locations are understood not to limit the locations of these components.

Similarly, components of the icemaker200also can be disposed in various locations within the refrigerator100, and are not limited to those exemplary locations depicted in the drawings. It is contemplated that in embodiments of the invention the storage tank206and the pump230are disposed next to a back wall of the freezer compartment104and behind a freezer evaporator cover. The medium is cooled by the absorption of heat by the refrigerant undergoing expansion, in the manner described above. However, these components are not limited to such locations within the refrigerator100.