Patent Application
20120324916
1. Field of the Invention
The present invention pertains to the art of ice making and, more particularly, to icemakers which produce clear ice pieces.
2. Description of the Related Art
In general, ice pieces produced with standard icemakers 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 icemakers which produce clear ice pieces. One approach to preventing the formation of cloudy ice is by agitating or moving water in an ice try 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. However, this type of icemaker requires multiple moving parts which make production and maintenance of the icemaker more costly.
Additionally, it is known in the art to produce ice cubes by freezing water about the periphery of evaporator fingers. For example, U.S. Patent Application Publication No. 2010/0218518 feeds water to a first cavity of a multi-cavity mold, where it cascades into the next cavity until all the cavities are full. Fingers of an evaporator are located in the respective cavities, and ice pieces form on the fingers. The fingers are heated in order to release the formed ice pieces from the fingers and drop the ice into a container below. However, such systems do not provide the advantages of the clear icemakers discussed above. A similar system is also depicted in U.S. Pat. No. 6,742,351, which includes a cam motor that periodically rocks water freezing cells to remove air bubbles on the surface of evaporator fingers. Although this system improves ice quality by removing air bubbles on the surface of the evaporator fingers, there continues to be a need for alternative icemakers that provide improved ice quality and clarity using minimal moving parts.
The present invention is directed to a clear ice making system and method for use in a refrigerator. The clear ice making system utilizes an ice tray including a plurality of ice forming cavities spaced within a fluid supply cavity. Water supplied to the fluid supply cavity flows into each of the plurality of ice forming cavities and out through respective fluid outlets located in a bottom portion of the ice forming cavities to an outlet cavity below. The clear ice making system also includes an evaporator plate arranged in contact with an evaporator forming part of a refrigerant circulation system of the refrigerator. During an ice making event, a plurality of chilled ice forming fingers extending from the evaporator plate are inserted into the plurality of ice forming cavities. Fluid is continuously cycled through the ice forming cavities and around the ice forming members during an ice making event such that clear ice pieces gradually form on each of the ice forming members. During an ice harvest event, the ice forming members are heated to release formed ice pieces. In accordance with the preferred embodiment of the invention, the icemaker is located in a fresh food compartment of the refrigerator and the formed ice pieces are transferred from the fresh food compartment to an ice storage bucket located in a freezer compartment of the refrigerator.
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 temperature controlled bins 28 and 29, as well as a more conventional storage compartment 30. The above described refrigerator structure is known in the art and presented only for the sake of completeness. The present invention is particularly directed to a clear ice making system which is generally indicated at 50.
Details of an icemaker 52 utilized in clear ice making system 50 will now be discussed with reference to
An evaporator plate 74 located above ice tray 54 includes an evaporator 76 through which refrigerant flows during an ice making event as will be discussed in more detail below. Evaporator 76 is in communication with a plurality of ice forming members 78 extending from evaporator plate 74. Each ice forming member 78 is adapted to extend into a respective one of the ice forming cavities 70. In a manner known in the art, a compressor (not shown) establishes a flow of compressed refrigerant which is condensed via flowing through a condenser (not shown) and then through an expansion device (not shown) and subsequently directed into evaporator 76. Evaporator 76 is cooled by the expanding of the compressed refrigerant and, in turn, ice forming members 78 are also cooled. In accordance with the present invention, ice forming members 78 may be chilled through direct contact with refrigerant, such as by having hollow portions (not shown) of ice forming members 78 being in direct fluid communication with evaporator 76, or ice forming members 78 may be chilled through indirect contact with refrigerant flowing through evaporator 76, i.e., via conduction as shown in
Details of ice forming cavities 70 and the manner in which fluid is circulated through icemaker system 50 will now be discussed with reference to
Various methods of initiating an ice making cycle are known in the art, including providing a controller for initiating an ice making cycle based on the amount of ice stored within an ice bucket. In accordance with the present invention, a known method of initiating an ice making cycle may be utilized, and such details are not considered to be part of the present invention. Instead, the invention is particularly directed to the structure of ice making system 50 and the manner in which ice pieces 100 are produced and dispensed. During an ice making event, fluid is circulated between ice tray 54 of icemaker 52 and a fluid storage cavity indicated at 90 through one or more pumps 92. More specifically, pump 92 continuously supplies fluid from fluid storage cavity 90 to fluid supply cavity 58 through fluid supply line 64. In a preferred embodiment, fluid freely circulates throughout fluid supply cavity 58 through interconnecting fluid channels, indicated at 94, between each of ice forming cavities 70. Fluid rises within fluid supply cavity 58 until the level of fluid surpasses the height H1 of side walls 80 and overflows into each of fluid supply cavities 70. With reference to fluid supply cavity 70A, it can be seen that fluid flows around ice forming member 78 and out through fluid outlet 84 to fluid outlet chamber 60. From fluid outlet chamber 60, fluid is recirculated to fluid storage cavity 90 through fluid discharge line 66. With this configuration, fluid constantly flows into ice forming cavity 70A, around the cooled ice forming member 78 therein, and freezes on the surface of ice forming member 78, layer-by-layer over a period of time, to form a clear ice piece indicated at 100. In accordance with the invention, the constant flow of fluid over the forming ice and the layer-by-layer formation “cleans” the ice and enables the formation of clear ice pieces 100 without air bubbles or cloudiness.
In a preferred embodiment, fluid within ice making system 50 is periodically refreshed. More specifically, after a predetermined number of ice making cycles, a drain valve 101 is opened and fluid within fluid storage cavity 90 is drained through a drain line 102 to a refrigerator condensate pan or drain (not shown), and fresh fluid is supplied to the ice making system 50 via a fluid inlet 103. In the embodiment shown, fluid inlet 103 is in communication with fluid storage cavity 90, however, it should be understood that fluid inlet 103 could initially introduce water to ice making system 50 through ice tray 54. After a pre-determined amount of time, or based on another known method for determining the end of an ice production cycle, pump 92 is deactivated and fluid within ice tray 54 is drained into fluid storage cavity 90, either passively based on gravity or through the use of a pump 104.
During an ice dispensing cycle, a known ice-tray shifting method is utilized to shift ice tray 54 away from ice forming members 78 in order to release clear ice pieces formed thereon into a storage container or bin below. For example, as depicted in
Upon initiation of an ice harvesting cycle, ice forming members 78 are heated to melt a portion of the formed ice pieces 100 in contact with ice forming members 78 and release the ice pieces 100 from ice forming members 78. With reference to
In a preferred embodiment depicted in
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 depicted in connection with a moving ice tray, it should be understood that the evaporator plate could be configured to move instead of the ice tray during an ice harvesting event. In addition, although the storage cavity is depicted as located directly beneath the ice tray, it should be understood that the storage cavity could be located remote from the ice tray. Furthermore, although each fluid supply cavity is shown to include a single upper opening for receiving both a respective ice forming finger and a flow of water, separate openings could be provided, such as slots in the side wall to establish the desired water flow. In general, the invention is only intended to be limited by the scope of the following claims.
