TWIST TRAY ICE MAKER SYSTEM
Techniques for use in ice maker systems are disclosed. In one example, an ice tray apparatus includes an ice mold body formed substantially of a metal material, and a holder for holding the ice mold body, the holder including a rotation-stopping feature formed thereon. The ice tray assembly may be used in an ice maker system mounted in a storage compartment of a refrigerator appliance.
The subject matter disclosed herein relates to ice maker systems, and more particularly to improved techniques for harvesting ice from the ice mold body in which the ice is formed.
Existing twist tray ice maker systems have been used to automatically produce ice inside the freezer compartments of domestic refrigerator products. They operate by filling a flexible plastic ice mold (tray) with water. Once the water freezes, the mold is rotated upside down and twisted until the ice cubes fall out by gravity. The tray is then rotated back to its upright position and the cycle is started again.
These existing twist tray ice maker systems have several known failure modes. First, calcium deposits form on the plastic tray causing the ice cubes to stick inside the mold. When the tray is refilled, water overflows into the ice storage bucket. The overflow water freezes the cubes in the ice storage bucket causing the ice dispensing mechanism to jam. Second, because the ice mold is made of plastic, the rate of ice making is low due to the low thermal conductivity of plastic. Third, the plastic ice trays are known to break causing the entire system to jam or overflow.
BRIEF DESCRIPTION OF THE INVENTIONAs described herein, the exemplary embodiments of the present invention overcome one or more disadvantages known in the art.
One aspect of the present invention relates to an ice tray apparatus comprising: an ice mold body formed substantially of a metal material; and a holder for holding the ice mold body, the holder comprising a rotation-stopping feature formed thereon. In one illustrative embodiment, the holder may be formed substantially of a plastic material.
Another aspect of the present invention relates to an ice making apparatus comprising: an ice tray assembly; a frame for supporting the ice tray assembly; and a rotation assembly for rotating the ice tray assembly within the frame. The ice tray assembly comprises an ice mold body formed substantially of a metal material, and a holder for holding the ice mold body, the holder comprising a first rotation-stopping feature formed thereon. The frame comprises a second rotation-stopping feature formed to engage the first rotation-stopping feature on the holder.
Yet another aspect of the present invention relates to a refrigerator appliance comprising: a compartment; and an ice maker assembly mounted in the compartment. The ice maker assembly comprises: an ice tray assembly; a frame for supporting the ice tray assembly; and a rotation assembly for rotating the ice tray assembly within the frame. The ice tray assembly comprises an ice mold body formed substantially of a metal material, and a holder for holding the ice mold body, the holder comprising a first rotation-stopping feature formed thereon. The frame comprises a second rotation-stopping feature for engaging the first rotation-stopping feature on the holder.
Advantageously, in accordance with illustrative techniques of the invention, the use of a metal material for the ice mold body, which has a thermal conductivity significantly higher than that of plastic, improves the transfer of heat away from the water thereby increasing the amount of ice that can be made in a given period of time. The metal ice mold body is also more resistant to mineral deposit buildup. Furthermore, the use of a plastic holder for holding the metal ice mold body with a positive stop on the plastic holder provides for the flexibility and elastic deformation desirable to twist the ice mold body to release the ice there from without leading to significant fatigue fracture problems.
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, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.
In the drawings:
One or more of the embodiments of the invention will be described below in the context of an ice maker system in a refrigerator appliance, such as a household refrigerator. However, it is to be understood that techniques of the invention are not intended to be limited to ice maker systems in household refrigerators. Rather, techniques of the invention may be applied to and implemented in any other suitable environments in which it would be desirable to improve the reliability and ice making performance of an ice maker system.
Principles of the invention realize that to improve reliability and ice making performance, it is desirable to form the ice mold body or tray out of a metal material. Metal has a thermal conductivity much higher than that of plastic. This improves the transfer of heat away from the water thereby increasing the amount of ice that can be made in a given period of time. The use of metal also allows for the use of several non-stick coatings such as, by way of example only, a nanoceramic coating, a Teflon (trademark of DuPont) coating, or a Thermolon (trademark of Thermolon) coating. These coatings improve reliability by preventing a failed ice harvest, i.e., ice remaining in the tray after the ice harvesting cycle.
Furthermore, in order to provide for the flexibility and elastic deformation desirable to twist the metal ice mold body to release the ice during an ice harvesting cycle, principles of the invention realize that it is desirable to form the holder for holding the metal ice mold body out of a plastic material. However, materials other than plastic may be used to form all or substantial portions of the holder, by way of example, metals.
Accordingly, in embodiments of the invention, the ice tray assembly (ice mold body and holder) is manufactured from metal and plastic components. A metal tray can be formed from a flat metal sheet. The cups or cavities used to hold water while it freezes (ice formation cavities) are easily formed by common manufacturing processes. To twist the tray to release ice during an ice harvesting cycle, the metal tray is held in a plastic holder that provides the geometry desirable to flex the tray and harvest ice there from.
Illustrative embodiments of the inventive ice maker system will now be described. Embodiments with ice mold bodies having cube-shaped ice formation cavities are illustrated and described in the context of
It is to be appreciated that the ice mold body 112 need not be formed of a single type of metal. Also, the entire ice mold body 112 need not be completely formed of a metal material. That is, the ice mold body 112 may be substantially formed from a metal material so long as the ice mold body exhibits, for example, the comparatively high thermal conductivity, the ability to apply a non-stick coating, and the mineral deposit buildup prevention advantages afforded by a metal material. Examples of metal material that the ice mold body 112 include but are not limited to aluminum, stainless steel, or a copper, nickel, tin combination (e.g., C72500 in accordance with Unified Numbering System).
Likewise, it is to be appreciated that the holder 114 need not be formed of a single type of plastic. Also, the entire holder 114 need not be completely formed of a plastic material. That is, the holder 114 may be substantially formed from a plastic material so long as the holder exhibits, for example, the flexibility and elastic deformation desirable to twist the metal ice mold body to release the ice during an ice harvesting cycle. Examples of plastic material that the holder 114 include but are not limited to polypropylene.
It is also to be appreciated that while
As also shown in
As also shown in
As will be explained in accordance with
Returning to the ice maker assembly 100,
In this embodiment, the ice mold body 112 is held to the holder 114 via removable fasteners 602. Such removable fasteners may be any suitable type of removable fastener, for example, as shown in
In this embodiment, the ice mold body 112′ is held to the holder 114′ via support features 702 formed as part of the holder 114. Such support features may be any suitable type of support features, for example, as shown in
Also, it is to be appreciated that the support features and holder shown in
Turning now to
In one embodiment, the rotation assembly 410 applies a minimum rotational force (clockwise torque) of approximately 6 Newton meters (Nm) such that, when the first rotation-stopping feature (tab) 402 on the holder 114 and the second rotation-stopping feature (stopper block) 404 on the frame 120 engage or contact one another, the ice mold body 112 is twisted causing the ice mold body to temporarily deform and the ice formed therein to be released. That is, the tab on the holder contacts the stopper block on the frame causing the ice tray assembly to resist rotation so as to temporarily deform the ice mold body.
The rotational force applied by the motor causes the ice tray assembly 110 to rotate from a start position (e.g., horizontal) to a first rotational position at which the first rotation-stopping feature 402 and the second rotation-stopping feature 404 engage one another. This may be approximately 160 degrees in advance of the start position (which would be approximately 0 degrees). This first rotational position would be just short of the halfway position when the ice tray assembly is upside down (which would be approximately 180 degrees). This rotation-stopping contact position is shown in
The rotation assembly 410 continues to apply a clockwise torque of approximately 6 Nm rotational force to the ice tray assembly 110 to attempt to rotate the ice tray assembly to a second rotational position beyond the first rotational position. In one embodiment, the second rotational position is approximately 10 degrees in advance of the first rotational position or approximately 170 degrees (160+10 degrees).
Note that the operation is described as “attempting” to rotate the ice tray assembly to the second rotational position. Recall that the first rotation-stopping feature (tab) 402 on the holder 114 contacts the second rotation-stopping feature (stopper block) 404 on the frame 120 at the first rotational position thus causing the ice tray assembly 110 to resist rotation so as to temporarily deform the ice mold body 112. Thus, while the motor shaft of the rotation assembly 410 rotates about another 10 degrees past the first rotational position, the ice tray assembly 110 is resisting and thus the ice mold body 112 is axially flexing or twisting around the centerline B, causing the ice formed therein to be released and drop into an ice storage bucket (not shown) below the ice tray assembly.
After the motor shaft of the rotation assembly 410 rotates to the second rotational position (about another 10 degrees past the first rotational position), the rotation assembly 410 applies a reverse rotational force (counterclockwise torque) to the ice tray assembly 110 to rotate the ice tray assembly back to the start position (and back to its non-deformed state) for a next ice formation cycle to begin. After the next ice formation cycle, the ice harvesting cycle described above is repeated. Thus, the ice maker system automatically generates ice until the ice storage bucket is filled, which is typically signaled by a stop arm (not shown).
It is to be understood that the rotational positions mentioned above are examples and that one skilled in the art will realize other rotational positions that can be implemented depending on the flexibility, rigidity, and/or deformation characteristics of the ice mold body of the ice tray assembly.
Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to exemplary embodiments thereof, it will be understood that various omissions and 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. 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. Furthermore, 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.
Claims
1. An ice tray apparatus comprising:
- an ice mold body formed substantially of a metal material; and
- a holder for holding the ice mold body, the holder comprising a rotation-stopping feature formed thereon.
2. The ice tray apparatus of claim 1, wherein the holder is formed substantially of a plastic material.
3. The ice tray assembly of claim 2, wherein the plastic material of the ice mold body comprises polypropylene.
4. The ice tray apparatus of claim 1, wherein the ice mold body is held in the holder by one or more removable fasteners.
5. The ice tray apparatus of claim 1, wherein the ice mold body is held in the holder by one or more support features formed on the holder.
6. The ice tray apparatus of claim 1, wherein the ice mold body comprises a plurality of ice formation cavities.
7. The ice tray apparatus of claim 6, wherein the plurality of ice formation cavities have a non-stick coating applied thereon.
8. The ice tray apparatus of claim 1, wherein the rotation-stopping feature formed on the holder comprises a tab protruding from the holder.
9. The ice tray apparatus of claim 1, wherein the holder further comprises first and second rotation-enabling features respectively formed at distal ends of the holder.
10. The ice tray apparatus of claim 9, wherein one of the first and second rotation-enabling features comprises a shaft feature and another of the first and second rotation-enabling features comprises a slot feature.
11. The ice tray assembly of claim 1, wherein the metal material of the holder comprises one or more of aluminum, steel, copper, nickel, and tin.
12. An ice making apparatus comprising:
- an ice tray assembly comprising: an ice mold body formed substantially of a metal material; and a holder for holding the ice mold body, the holder comprising a first rotation-stopping feature formed thereon;
- a frame for supporting the ice tray assembly, the frame comprising a second rotation-stopping feature formed to engage the first rotation-stopping feature on the holder; and
- a rotation assembly for rotating the ice tray assembly within the frame.
13. The ice making apparatus of claim 12, wherein, following an ice formation cycle and at the start of an ice harvesting cycle, the rotation assembly rotates the ice tray assembly within the frame such that, when the first rotation-stopping feature and the second rotation-stopping feature engage one another, the ice mold body of the ice tray assembly is twisted causing the ice mold body to temporarily deform and the ice formed therein to be released.
14. The ice making apparatus of claim 13, wherein the first rotation-stopping feature formed on the holder comprises a tab protruding from the holder at an end opposite to a location of the rotation assembly and the second rotation-stopping feature formed on the frame comprises a stopper block protruding from the frame at an end opposite to the location of the rotation assembly.
15. The ice making apparatus of claim 14, wherein the tab on the holder contacts the stopper block on the frame causing the ice tray assembly to resist rotation so as to temporarily deform the ice mold body.
16. The ice making apparatus of claim 12, wherein the rotation assembly applies a rotational force to the ice tray assembly to rotate the ice tray assembly from a start position to a first rotational position at which the first rotation-stopping feature and the second rotation-stopping feature engage one another.
17. The ice making apparatus of claim 16, wherein the rotation assembly continues to apply a rotational force to the ice tray assembly to attempt to rotate the ice tray assembly to a second rotational position beyond the first rotational position.
18. The ice making apparatus of claim 17, wherein the rotation assembly applies a reverse rotational force to the ice tray assembly to rotate the ice tray assembly back to the start position for a next ice formation cycle to begin.
19. The ice making apparatus of claim 17, wherein the first rotational position is approximately 160 degrees in advance of the start position, and the second rotational position is approximately 10 degrees in advance of the first rotational position.
20. A refrigerator appliance comprising:
- a compartment; and
- an ice maker assembly mounted in the compartment and comprising: an ice tray assembly comprising: an ice mold body formed substantially of a metal material; and a holder for holding the ice mold body, the holder comprising a first rotation-stopping feature formed thereon; a frame for supporting the ice tray assembly, the frame comprising a second rotation-stopping feature for engaging the first rotation-stopping feature on the holder; and a rotation assembly for rotating the ice tray assembly within the frame.
Type: Application
Filed: Jul 28, 2010
Publication Date: Feb 2, 2012
Inventors: Carlos A. HERRERA (Louisville, KY), Alan Joseph Mitchell (Louisville, KY), Yogesh Kumar Allimalli (Louisville, KY)
Application Number: 12/844,894
International Classification: F25C 1/04 (20060101); F25C 1/22 (20060101);