The present invention relates generally to refrigerators with icemakers housed within the fresh food compartment, and more specifically, to methods and apparatus for cooling icemakers in such refrigerators.
Generally, a refrigerator includes an evaporator, a compressor, a condenser, and an expansion device.
The evaporator receives coolant from the refrigerator in a closed loop configuration where the coolant is expanded to a low pressure and temperature state to cool the space and objects within the refrigerator.
It is also now common in the art of refrigerators, to provide an automatic icemaker. In a “side-by-side” type refrigerator where the freezer compartment is arranged to the side of the fresh food compartment, the icemaker is usually disposed in the freezer compartment and delivers ice through an opening in the access door of the freezer compartment. In this arrangement, ice is formed by freezing water with cold air in the freezer compartment, the air being made cold by the cooling system or circuit of the refrigerator. In a “bottom freezer” type refrigerator where the freezer compartment is arranged below a top fresh food compartment, convenience necessitates that the icemaker be disposed in the access door of the top mounted fresh food compartment and deliver ice through an opening in the access door of the fresh food compartment, rather than through the access door of the freezer compartment. It is known in the art, that a way to form ice in this configuration is to deliver cold air, which is cooled by the evaporator of the cooling system, through an interior cavity of the access door of the fresh food compartment to the icemaker to maintain the icemaker at a temperature below the freezing point of water.
When a liquid coolant is used to cool the ice mold body, the heating of the ice mold body heats the liquid coolant within the ice mold body. This requires more energy to be expended than would be required to heat the ice mold body itself because not only does the material of the ice mold body need to be heated to a temperature above the freezing point of water, the mass of coolant contained within the ice mold body must also be heated. This heated coolant must subsequently be cooled again so that more ice can be formed. This process increases ice production time because of the extra time required to heat the coolant within the ice mold body, and the extra time required to cool the heated coolant for production of new ice.
Therefore, an ability to operate more efficiently, both in speed of ice preparation and maintenance of the refrigerator is desired. Therefore, it would be desirable to provide a method and apparatus for making maintenance and ice production more efficient.
As described herein, the exemplary embodiments of the present invention overcome one or more of the above or other disadvantages known in the art.
One aspect of the present invention relates to a method of cooling an icemaker. The icemaker comprises an ice mold body having a channel for transport of coolant and a plurality of ice cavities. The method comprises the steps of: injecting a coolant into the channel, adding water to the ice cavities, forming ice cubes in the ice cavities, removing coolant from the channel, heating the ice mold body, and ejecting the ice cubes from the ice mold body.
Another aspect relates to a refrigerator. The refrigerator comprises a food storage compartment, an access door operable to selectively close the food storage compartment, an icemaker compartment mounted on the access door, an icemaker disposed in the icemaker compartment and comprising an ice mold body, the ice mold body defining therein a plurality of ice cavities for containing water therein for freezing into ice cubes, and a channel for transport of a coolant within the ice mold body, at least one heating element attached to the ice mold body, a reversible coolant pump, a conduit for transport of a coolant between the ice mold body and the reversible coolant pump, and a controller for regulating the reversible coolant pump direction.
Another aspect of the present invention relates to a method of removing a door from a main body of a refrigerator. The door includes an icemaker compartment, and an ice mold body is disposed in the icemaker compartment and has a plurality of ice cavities for containing water therein for freezing into ice cubes. A conduit extends from the main body into the icemaker compartment for delivering an ice forming medium to the icemaker compartment. The refrigerator has a reversible pump for moving the ice forming medium from a tank to the icemaker compartment along the conduit. The method includes reversing a direction of the reversible pump to move the ice forming medium from the icemaker compartment back to the tank; and separating the door from the main body after the door is substantially free of the ice forming medium.
These and other aspects and advantages of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. Moreover, the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.
On the exterior of the refrigerator 10, there is an external recessed access area 49 for dispensing of drinking water and ice cubes. Upon a stimulus, a water dispenser 50 allows an outflow of drinking water into a user's receptacle (not shown). Upon another stimulus, an ice dispenser 52 allows an outflow of ice cubes into a user's receptacle. There are two access doors, 32 and 34, to the fresh food compartment 12, and one access door 33 to the freezer compartment 14. Refrigerator 10 is contained within an outer case 16.
The insulation in the space between the bottom wall of liner 18 and the top wall of liner 20 is covered by another strip of suitable resilient material, which also commonly is referred to as a mullion 22. Mullion 22 in one embodiment is formed of an extruded ABS material.
Shelf 24 and slide-out drawer 26 can be provided in fresh food compartment 12 to support items being stored therein. A combination of shelves, such as shelf 28 is provided in freezer compartment 14.
Left side fresh food compartment door 32, right side fresh food compartment door 34, and a freezer door 33 close access openings to fresh food compartment 12 and freezer compartment 14, respectively. In one embodiment, each of the doors 32, 34 are mounted by a top hinge assembly 36 and a bottom hinge assembly (not shown) to rotate about its outer vertical edge between a closed position, as shown in
The sealed system 150 has a compressor 151 for compressing a working medium. When compressed, the working medium becomes heated. The working medium is decompressed or vaporized at expansion device 155 thereby decreasing the temperature of the working medium. The working medium passes through heat exchanger 310 before entering evaporator 156. Evaporator 156 may have a fan 157 to circulate air from freezer compartment 14 (as seen in
Referring back to
The icemaker compartment 30 includes an ice mold body 120, having a channel 212 for the transport of coolant within ice mold body 120. Components of the system to distribute coolant include a coil 312, channel 212, a second heat exchanger 230, a tank 301, a reversible coolant pump 302, and a coolant conduit 303 for transport of the coolant between channel 212 and the reversible coolant pump 302. Coil 312, reversible coolant pump 302, and tank 301 may be disposed in freezer compartment 14.
Heat exchanger 310 has coil 311 as a part of the sealed system 150 and coil 312 as a part of the system to distribute coolant to icemaker compartment 30. Coil 311 and coil 312 are operatively coupled in a heat exchange relationship either through direct contact or indirectly through a thermally conductive medium such as a working fluid. In the exemplary embodiment of
Second heat exchanger 230 thermally connects the coolant with the icemaker compartment 30. Channel 212 also thermally connects the coolant to the interior of the icemaker compartment 30, and specifically the interior of ice mold body 120.
When the coolant is a liquid, such as a food safe liquid in the nature of a mixture of propylene glycol and water, distribution of coolant to the icemaker compartment 30 can be achieved as follows. Transport of the coolant within refrigerator 10 includes the coolant passing through heat exchanger 310, second heat exchanger 230, and reversible coolant pump 302, which delivers the pressure to circulate the coolant within icemaker compartment 30. Second heat exchanger 230 thermally couples the circulating coolant in a heat exchange relationship with the ice mold directly or indirectly. In the exemplary embodiment of
When operating in the cooling mode, the reversible coolant pump 302 is circulating coolant in a substantially counter-clockwise direction, shown by arrows 228 in
Reversible coolant pump 302 can also operate in a reverse direction, as shown by arrows 227. When reversible coolant pump 302 operates in a reverse direction, creating a negative pressure, the coolant that is in channel 212 gets removed, leaving channel 212 substantially empty. It is helpful to remove the coolant from the channel 212 during ice harvest when the ice mold body is typically heated to a temperature above the freezing point of water so that the ice cubes melt slightly and can be ejected from the ice mold body more easily; otherwise, additional energy will be used to heat the coolant. This volume of coolant from channel 212 travels along the path indicated by arrows 227 and extra volume is stored within tank 301. Port 237 in tank 301 can be used by a service professional to add additional volume of coolant to the system, or remove extra coolant volume.
Ice mold body 120 includes rake 132 which extends from control housing 140 along open top 122. Rake 132 includes individual fingers 134 received within each of the ice cavities 133 of ice mold body 120. In operation, rake 132 is rotated about an axis of rotation or rake axis 136 that extends generally parallel to front face 126 and rear face 128. A motor (not shown) is housed within control housing 140 and is used for turning or rotating rake 132 about axis of rotation 136.
In the exemplary embodiment, control housing 140 is provided at mounting end 112 of ice mold body 120. Control housing 140 includes a housing body 142 and an end cover 144 attached to housing body 142. Housing body 142 extends between a first end 146 and a second end 148. First end 146 is secured to mounting end 112 of ice mold body 120. Alternatively, housing body 142 and ice mold body 120 are integrally formed. The end cover 144 is coupled to second end 148 of housing body 142 and closes access to housing body 142. In an alternative embodiment, end cover 144 is integrally formed with housing body 142. Housing body 142 houses a motor and/or the controller (as seen in
A plurality of partition walls 220 extend transversely across ice mold body 120 to define the plurality of ice cavities 133 in which ice cubes 242 can be formed. Each partition wall 220 includes a recessed upper edge portion 222 by which water flows successively through and substantially fills the plurality of ice cavities 133 of ice mold body 120.
In this embodiment, two sheathed electrical resistance heating elements 224 are attached, such as by press-fitting, staking, and/or clamping into bottom support structure 226 of ice mold body 120. The heating elements 224 heat ice mold body 120 when a harvest cycle begins in order to slightly melt ice cubes 242 to allow the ice cubes to be released from ice cavities 133. Rotating rake 132 sweeps through ice mold body 120 as ice cubes are harvested and ejects the ice cubes from ice mold body 120 into ice storage bin 240. Cyclical operation of heating elements 224 and rake 132 are effected by controller 305, which also automatically provides for refilling ice mold body 120 with water for ice formation after ice is harvested.
The method of ice making in one aspect of the invention contains several steps. At the beginning of the cycle, the plurality of ice cavities 133 in ice mold body 120 are substantially empty of water and channel 212 within the ice mold body is substantially empty. A coolant is then injected into channel 212 through inlet 214. Water is added to the exterior of ice mold body 120, separated by a plurality of partition walls 220, substantially filling the plurality of ice cavities 133. The coolant within channel 212 cause the water in the ice mold body 120 to substantially freeze, and form ice cubes 242. After substantial freezing of the water in ice mold body 120, the coolant in channel 212 is removed through coolant outlet 216, leaving channel 212 substantially empty. Upon substantial emptying of channel 212, the heating elements 224 are activated, increasing the temperature of ice mold body 120. After a predetermined period of heating, rake 132 rotates along axis 136 causing the fingers 134 to eject the formed solid ice cubes 242. After ejection of ice cubes 242, the heating elements 224 are deactivated, allowing the ice mold body 120 to cool. After a pre-determined time, coolant is injected into channel 212 through inlet 214, and the cycle begins again. In other words, these steps are repeated one or more times.
Controller 305 is operatively connected to temperature sensor 218 which is in thermal communication with ice mold body 120. Controller 305 operates rake 132, and controls the addition of water for ice cubes, energization of the heating elements 224 and both injection and withdrawal of coolant from channel 212, based on values determined by temperature sensor 218. Controller also is also operatively connected to sealed system 150, and can call for operation of compressor 151, condenser 152, expansion device 155, and evaporator 156 if further cooling of freezer compartment 14 or second heat exchanger 230 is needed.
The fundamental novel features of the invention as applied to various specific embodiments thereof have been shown, described and pointed out, it will also be understood that various omissions, substitutions and changes in the form and details of the devices illustrated and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, the coolant pump 302 can be operated in a reverse direction to pump the coolant out of the channel 212 and the coolant conduit 303 before the door 32 is separated or removed from the main body of the refrigerator 10. Moreover, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.