1. Field of the Invention
The present invention pertains to the art of refrigerators and, more particularly, to ice makers for producing clear ice pieces.
2. Description of the Related Art
In general, ice pieces produced with standard ice makers tend to include air bubbles or other imperfections that lend a cloudy or impure appearance to the ice. Therefore, there has been an interest in constructing ice makers which produce clear ice pieces. One approach to preventing the formation of cloudy ice is to agitate or move water in an ice tray during the freezing process. For example, U.S. Pat. No. 4,199,956 teaches an ice making method wherein a plurality of freezing elements are immersed in a pan of water which is agitated by a plurality of paddles during a freezing process. This type of ice maker requires water to be added to the pan every new freezing cycle, and may lead to minerals or other impurities concentrating or collecting in the pan over time. Another approach utilizes the continuous flow of water over a vertical ice-forming plate in a refrigerator compartment to produce ice having a higher purity then that of the original tap water. Specifically, multiple spaced points located on the vertical ice-forming plate are in contact with an evaporator line such that water flowing over the spaced points freezes in layers over time, gradually forming a plurality of ice pieces. In order to harvest the ice pieces, hot refrigerant gas flows into the evaporator line, the warming effect detaches the ice pieces from the ice-forming plate, and the ice pieces fall into an ice bin within the refrigerator compartment. However, large spaces must be left between the contact points of the evaporator in order to prevent ice bridges from developing between ice pieces, thus requiring either relatively large quantities of water to flow over the multiple spaced points, or fewer spaced points. Additionally, this system utilizes the refrigerator's main evaporator, thus requiring the icemaker system to be configured around the location of the main evaporator. Further, ice pieces collected in the ice bin melt over time, which results in diminished ice quality.
Regardless of these known prior art arrangements, there is seen to be a need in the art for an improved ice maker that can be utilized with various refrigerator configurations and produce high quality clear ice pieces utilizing minimal amounts of water.
The present invention is directed to an ice making assembly and method for a refrigerator which utilizes an ice maker including an upper fluid chamber which supplies fluid to a plurality of distinct, substantially vertical, fluid channels. Ice forming members of an evaporator extend into the substantially vertical fluid channels and are cooled by communication with the refrigerant circulation system of the refrigerator. During an ice making cycle, fluid is continuously supplied to the upper fluid chamber, resulting in streams or sheets of fluid flowing through each of the substantially vertical fluid channels and cascading over the ice forming members therein. Fluid contacting the ice forming members freezes, forming clear ice pieces based on the shape of the ice forming members. The remaining cascades of fluid drain through at least one drain aperture located in the icemaker housing, and into a fluid reservoir below. A pump is utilized to recirculate fluid from the fluid reservoir to the upper fluid chamber.
During an ice harvest event, the ice forming members are heated to release ice pieces formed thereon, and the ice pieces are released from the ice maker. In a preferred embodiment, the ice maker is located with a fresh food compartment of the refrigerator. After ice pieces are released from the ice maker, they are transferred from the fresh food compartment to an ice storage bucket located in a freezer compartment of the refrigerator. After a predetermined period of time or after a predetermined number of ice making cycles, fluid from within the fluid reservoir is drained and a fresh supply of fluid is added to the ice forming apparatus.
Additional objects, features and advantages of the present invention will become more readily apparent from the following detailed description of preferred embodiments when taken in conjunction with the drawings wherein like reference numerals refer to corresponding parts in the several views.
With initial reference to
In a manner known in the art, fresh food compartment 8 is provided with a plurality of vertically, height adjustable shelves 20-22 supported by a pair of shelf support rails, one of which is indicated at 25. At a lowermost portion of fresh food compartment 8 is illustrated various vertically spaced bins 28-30. At this point, it should be recognized that the above described refrigerator structure is known in the art and presented only for the sake of completeness. The present invention is not limited for use with a side-by-side style refrigerator shown, but may be utilized with other known refrigerator styles including top-mount, bottom-mount, or French door style refrigerators. Instead, the present invention is particularly directed to a clear ice making assembly which is generally indicated at 50.
Details of an ice maker 52 utilized in clear ice making assembly 50 will now be discussed with reference to
During assembly of ice maker 52, ice forming evaporator member 58 is sandwiched between first and second fluid channeling portions 62 and 63. Back plate 64, which is preferably constructed of an insulating material, such as foam, plastic or the like, is fit within the first and second fluid channeling portions 62 and 63 before top cover 60 and bottom fluid recycling portion 66 are connected to the first and second fluid channeling portions 62 and 63 to form a complete housing 54. More specifically, first and second fluid channeling portions 62 and 63 are snap-fit or otherwise mechanically connected together through flanges 68A-68F and 69A-69F (shown in
Between adjacent ones of channel walls 82A-82F are spaced, distinct and substantially vertical fluid channels 84A-84E, with one ice forming member 72 extending into a respective one of the multiple vertical fluid channels 84A-84E. Each vertical fluid channel 84A-84E includes at least one drain aperture 86A-86E formed in a sloped front face portion 87 of second fluid channeling portion 63, with each of the drain apertures 86A-86E being in fluid communication with a fluid reservoir 88 defined by bottom fluid recycling portion 66 (see
As best shown in
Upon initiation of an ice making event, water is continuously supplied to top fluid channel 92 via fluid inlet 94. Water fills upper fluid chamber 92 and flows downward into respective fluid channels 84A-84E through fluid inlet apertures 96A-96E formed in housing 54. As shown, fluid inlet apertures 96A-96E are preferably in the form of narrow, elongated slots. Streams or sheets of water flow vertically through each of the respective vertical fluid channels 84A-84E and across ice forming members 72, with any of the fluid which reaches drain apertures 86A-86E draining through an opening 97 in a bottom wall 98 of back plate 64 to enter fluid recycling portion 66. Fluid inlet apertures 96A-96E are preferably centered above respective ice forming members 72 such that fluid streams cascade over the entire face of ice forming members 72 before entering fluid reservoir 88. As depicted in
In accordance with the present invention, ice forming members 72 are preferably chilled through direct contact with refrigerant, such as the flow of refrigerant through hollow portions (not shown) of ice forming members 72, or ice forming members 72 may be chilled through indirect contact with refrigerant flowing through refrigerant line 70 (i.e., via conduction). In any event, fluid streams flowing through vertical fluid channels 84A-84E will flow over chilled ice forming members 72, preferably in a laminar fashion, resulting in the continuous formation of successive, thin ice layers on the chilled ice forming members 72, which build up over time to form clear ice pieces. Advantageously, such thin ice layers prevent air bubbles from forming, and the constant flow of water over the forming ice pieces “cleans” the ice pieces as they form, enabling the formation of clear ice pieces without air bubbles and cloudiness associated with the formation of standard ice pieces. In a preferred embodiment, ice forming evaporator member 58 is formed from a material having high thermal conductivity, such as copper, and first and second fluid channeling portions 62 and 63 are formed from a plastic material having a lower thermal conductivity than ice forming evaporator member 58. Alternatively, or in addition, first and second fluid channeling portions 62 and 63 could be provided with a phobic or hydrophobic coating. With this configuration, ice only forms on ice forming members 72 during an ice production cycle, thereby forming clear and distinctly shaped individual ice pieces without any undesirable bridging between the ice pieces.
After a predetermined amount of time, or based on another known method for determining the end of an ice production cycle, ice forming members 72 are heated to melt the portions of the ice pieces in direct contact with chilled ice forming members 72 in order to release the ice pieces from the ice forming members 72. Heating of ice forming members 72 may be accomplished through the use of a heating element, such as an electric resistive heating element in heating relationship with ice forming members 72, or through the use of gaseous refrigerant, which is circulated through ice forming evaporator member 58. Preferably, one or more valves indicated at 102 and 103 (
As depicted in
Based on the above, it can be seen that a multi-piece housing fits together about an ice forming evaporator, and defines spaced, distinct, and substantially vertical fluid channels. An upper fluid chamber, also defined by the housing, feeds fluid into each of the fluid channels, causing thin layers of ice to successively form on the ice forming members extending into each of the fluid channels and build up over time to form ice pieces having a desired size and shape. As discussed above, the ice maker of the invention includes its own dedicated ice forming evaporator which is adapted to connect to the refrigerator circulation system of any type of refrigerator unit. With this modular configuration, the ice maker can be placed anywhere within a refrigerator. The result is an ice making system that has a wide range of applications and utilizes minimal amounts of fluid to form clear ice pieces which can be stored in a freezer compartment to prevent wasteful melting of the ice pieces over time.
Although described with reference to preferred embodiments of the invention, it should be readily understood that various changes and/or modifications can be made to the invention without departing from the spirit thereof. For instance, although shown in the form of slots, the drain apertures could be in the form of drain holes, or may be any other type of aperture allowing fluid to drain into the fluid reservoir. In addition, although multiple, horizontally arranged ice forming members are shown, it should be understood that multiple, vertically arranged ice forming members could also be employed. Furthermore, although the invention has been described with reference to the depicted domestic refrigerator, the invention can also be employed in dedicated ice making machines, whether self-contained, under counter or countertop units. Finally, it should also be understood that various arrangements could be utilized to cool the ice forming members. That is, directing refrigerant from the main cooling system of the refrigerator is described in the preferred embodiment, but other cooling systems, such as a secondary refrigerant loop or a Peltier (thermoelectric) cooling arrangement, could be employed. In general, the invention is only intended to be limited by the scope of the following claims.