US3584470A - Centrifugal ice maker - Google Patents

Abstract

Centrifugal ice freezing apparatus including a plurality of flexible or otherwise deformable molds or pockets disposed in circular array, and having open portions presented radially inwardly toward a central axis about which they are rotatable. Means is provided for filling the pockets, and for rotating them to retain water therein by centrifugal force. While rotating, the molds are flexed and pivoted to ice freezing position, and are subjected to below freezing temperatures until the water is frozen. Upon freezing of the water, rotation is halted to accommodate both flexing and pivoting of the molds to ice ejecting position. An extensible and retractible mold striker is movable into extended position in which it is impacted sequentially by the pivoted molds to facilitate release of the ice from the molds.

Description

United States Patent 3,048.986 8/1962 Archer.

[72] inventor Elmer W. Zearfoss, Jr.

Philadelphia, Pa. 836,793

Primary Examiner-william E Wayner N0 June 26, 1969 Attorney-Carl H. Synnestvedt [45] Patented June 1S, 1971 [73] Assignee Philco-Ford Corporation phlladelphlapa' ABSTRACT: Centrifugal ice freezing apparatus including a plurality of flexible or otherwise deformable molds or pockets {54] CENTRIFUGAL [CE MAKER disposed in circular array, and having open portions presented 9 Claimsg Drawing Figs radially inwardly toward a central axis about which they are rotatable. Means is provided for filling the pockets, and for rotating them to retain water therein by centrifugal force. While rotating, the molds are flexed and pivoted to ice freezing position, and are subjected to below freezing temperatures until the water is frozen Upon freezing of the water, rotation is halted to accommodate both flexing and pivoting of the molds to ice ejecting position. An extensible and retractible mold striker is movable into extended position in which it is impacted sequentially by the pivoted molds to facilitate release of the ice from the molds.

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2,986,013 Zearf0ss, lr. 62/345 X CENTRIFUGAL ICE MAKER CROSS-REFERENCE TO RELATED DISCLOSURE This invention is directed to improvements in ice making apparatus of the type disclosed and claimed in my US. Pat. No. 2,986,013, issued May 30, 1961, and assigned to the assignee of the present invention.

BACKGROUND OF THE INVENTION The field of the invention is ice making, and more particularly apparatus for automatically freezing and harvesting ice masses. While of broader applicability, apparatus of this invention has particular utility in the field of household refrigerators.

The referenced disclosure has taught centrifugal ice mold structure in which harvesting of the ice masses is achieved through automatic pivotation and/or flexure of the individual molds. The present invention contemplates improved structure for achieving such flexure and pivotation, and which structure ensures repeated pivotal movements of the molds to enhance harvesting of the ice masses.

It is therefore a general objective of the invention to provide improvements in centrifugal ice molding and harvesting apparatus.

SUMMARY OF THE INVENTION The invention contemplates, in a preferred embodiment thereof, improvements in ice mold structure of the kind including a plurality of flexible pockets disposed in generally circular array, which pockets have open portions presented radially inwardly toward means defining a central axis about which the mold is rotatable. In especial accordance with the invention, each of the flexible pockets is supported by a leaf spring extending between opposed peripheral edge portions of a pocket. The pocket-supporting leaf spring is carried in the region of its center by a cantilevered, vertically pivotable arm which, when the mold is at rest, extends to a position such that the supported pockets are displaced slightly downwardly relative to their plane of rotation. Means is provided for filling the mold pockets with water, at which time the pockets are rotated to retain the water centrifugally therein. In response to centrifuging of the mold the said cantilevered arms pivot to horizontal position, displacing the pockets upwardly, and the leaf springs are bowed, forcing the supported edge portions of each pocket to a distorted position which the pocket occupies during the freezing of ice therein. After freezing, the mold is decelerated and the pockets return toward their undistorted, downwardly displaced position. As the mold is decelerated, an extensible mold striker is moved into extended position in which it impacts the downwardly displaced mold pockets. Flexure of the mold pockets from distorted toward undistorted position, in combination with impacting of the striker therewith, loosens the ice masses which are then free to slide out ofthe pockets.

The foregoing as well as other features and advantages of the invention will be more clearly understood from a consideration of the following description, taken in light of the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side elevational showing, in section, of a domestic refrigerator including ice making and harvesting apparatus embodying the invention;

FIG. 2 is a somewhat enlarged perspective showing, with parts removed, of the ice making and harvesting apparatus seen in FIG. 1;

FIG. 3 is an elevational view, partly in section, of a portion of the ice making apparatus seen in FIG. 2, as viewed generally in the direction of arrows 3-3 applied toFlG. 2, and showing an operational feature of the apparatus;

FIG. 4 is a view of a portion of the ice making and harvesting apparatus shown in FIG. 3 as seen. looking generally in the direction of arrows 4-4 applied thereto;

FIGS. 5 and 6 are views similar to FIGS. 3 and 4, respectively, and illustrating the apparatus shown in the preceding figures under operating conditions subject to centrifugal force;

FIG. 7 is a wiring diagram illustrating control circuit elements for the ice making apparatus illustrated in the preceding figures; and

FIG. 8 is a time chart illustrating the sequence of operation of elements of the apparatus illustrated in FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT With more particular reference to FIG. I, a refrigerator cabinet 10 of conventional design includes a food storage compartment 11 and a freezer compartment 12. A single evaporator 13 is disposed in a compartment adjacent the rear of freezer compartment 12, and a fan 14 is arranged to move air over evaporator I3 and through both the freezer compartment and the food compartment by way of suitably formed air duct means, such air movement being indicated generally by flow arrows. Evaporator 13 is connected, in the usual series refrigerant flow circuit, with a conventional refrigerant expansion device (not shown), and a motor compressor 15 and condenser 16 disposed in a suitable compartment through which air is drawn by a fan I9. Conveniently, the refrigerator is automatically defrostable, and includes means (not shown) for heating evaporator 13, and drain conduit means 17 arranged to direct defrost water into a disposal pan 18 also located in the condensing unit compartment.

In particular accordance with the invention, ice masses, or cubes", are frozen in mold means 22 carried by the rotatable shaft 23 of a motor 24 conveniently mounted in the region of the upper wall 25 of cabinet 10. A container 26 is disposed upon the floor of freezer compartment 12 and beneath mold means 22. Ice cubes will fall from the mold means into the container, to be stored therein in accordance with principles of the invention described more fully below.

With particular reference to FIG. 2, the ice mold means 22 comprises an open-top, generally cylindrical receptacle 27 mounted for rotatable movements about a vertically extending axis upon the similarly extending motor shaft 23. Cantilevered arms 31 are supported for generally vertical pivotal movements on the rim portion 270 of receptacle 27 and terminate in transversely extending leaf spring members 32 that support mold pockets or members 33, through screws 5 that extend into tabs 34 provided at opposite rim portions of the cups 33. As best seen in FIGS. 3 and 5, pivotal support of the arms 31 is afforded by the extension of their inner ends, with clearance, into generally rectangular recesses defined by embossments 37 on the rim portion of receptacle 27, in combination with pins 41 anchored in the rim portion 27a and extending both generally vertically across the recesses and with slight clearance through holes (not shown) in the arms.

A generally radially presented nozzle 35 is provided for each mold cup 33 in the upper rim portion of receptacle 27. Each nozzle 35 communicates with the interior of the receptacle and is angled slightly with respect to the vertical mid-plane of an associated mold cup 33, in the direction of rotation of motor shaft 23. Also, each nozzle 35 is disposed above the level ofa transversely extending member 32, to ensure against impingement of water thereon as it is directed into the corresponding mold pocket 33. The construction and arrangement is such that as motor 24 is energized to rotate receptacle 27, streams of water are directed centrifugally into the mold cups. The angular disposition of the nozzles compensates for the tendency of the streams of water to lag the nozzles. Also the nozzles 35 terminate a predetermined radial distance away from the pivotal mounts for arms 31 to ensure against impingement and subsequent freezeup of water thereon, which condition could prevent pivotation of the arm. Conveniently, the bores of nozzle 35 are of generally elliptical shape, with their major axes extending in the plane of mold rotation. This shape has been found to aid in preventing freezeup of water in the nozzles.

Apparatus for metering water for charging the mold means 22 provides sufficient water to fill each of the mold cups 33, without overflowing, for each filling of receptacle 27. Although no detailed description of the metering apparatus per se will be undertaken, there is illustrated, fragmentarily, a fill pipe 36 extending from such metering apparatus into the central opening of receptacle 27. A water supply valve 47 for the fill pipe is shown in FIG. 7, and will be described in more detail below, in conjunction with control circuit elements illustrated in that figure.

With particular reference to FIGS. 5 and 6, while the streams of water centrifuged from receptacle 27 fill the rotating mold cups 33, centrifugal force acting on the mass of the water causes each cup to be flexed so that its supported rim portions move toward one another. Flexure of the mold cups is accommodated by bowing of the leaf spring 32 (compare FIGS. 4 and 6) extending across the cup. Concurrent with mold cup flexure, downwardly tilted arms 3i pivot upwardly to a substantially horizontal position (FIG. 5), maintaining substantial verticality of the plane of the opening of each mold cup 33. After centrifuging of the mold means for a suitable time, at a suitable temperature below the freezing point of water, motor 24 is deenergized, whereupon the rotating mold cups 33 decelerate to rest position. In so doing, leaf springs 32 Spanning the openings of the mold cups 33 return to rest positions (FIG. 4), urging the sides of the mold cups to their undistorted rest positions. Concurrent with this flexure, the horizontally positioned arms 31 pivot downwardly to their rest positions, such as are shown in FIGS. 2 to 4. In especial accordance with the invention, a cylindrical member 42 is mounted on an eccentric journal, by means described below, and is rotatable into the path of the mold cups 33 as they approach their lower, rest positions. By this arrangement, member 42 is caused to impact the downwardly displaced mold cups 33 sequentially as they rotate past said member. Striking, or impacting with, the mold cups has been found to loosen the ice masses and ensure positive release thereof during the harvesting phase of an ice making cycle.

Further to facilitate ejection of the ice masses, a pad 39 of thermally insulative material is affixed to the rear of each mold cup 33 to ensure that water in this region of the cup will be the last to freeze. Upon freezing it expands and aids in release of the ice mass from the surface of the mold cup. Polytetrafluoroethylene, available under the trademark Teflon, has been found suitable for the mold cups 33, and foam polyurethane has been found suitable for the insulative pad 39.

Referring particularly to FIG. 7, control circuit elements for achieving the above-described ice making and harvesting cycle comprise a source of voltage V one side of which is connected to: a biasing heater 44 through a switch 45 controlled by the level of ice in bin 26; a water fill valve 47; timer motor 53; and drive motor 24. The other side of voltage source V is connected to bimetal switch 43, the latter including a cold contact F connected to the other end of heater 44, and a warm contact E connected to a timer contact B and to the other side of motor 24. Contact F is electrically connected to timer contact C, and the other side of the water fill valve 47 is connected to timer contact D. Timer 46 includes a pair of switch arms A, A connected to the other side of timer motor 53. Switch arm A is controllable by timer cam 51 to engage either contact B or C, and arm A is controllable by cam 51 to engage or disengage contact D.

Bimetal switch 43 is indirectly subjected to the temperature of the freezing compartment through a small quantity of water, in a suitable container (not shown), that alternately is frozen and is thawed, the latter being effected by biasing heater 44. In this way the bimetal switch is cycled, and its operation upon freezing of the small quantity of water is representative of freezing of the water in mold cups 33.

In operation, and with reference both to FIG. 7 and to the time chart in FIG. 8, assume that: ice bin switch 45 is closed to call for more ice; cold contact F of bimetal switch 43 is closed; shaft 52 of timer 46 is in such position that cam 51 closes contacts AC; and contact E of switch 43 has just been opened, so that motor 24 has just been deenergized to permit mold means 22 to coast to a stop. While mold means 22 is coasting, timer motor 53 is energized through cold contact F and contacts A-C for 10 seconds (FIG. 8) to rotate timer shaft 52 an amount sufficient to rotate mold striker 42 mounted eccentrically thereon through into interference relation with mold cups 33, as shown in FIGS. 3, 4, and 7. Striker 42 impacts with mold cups 33 to free the ice masses which are then dislodged and fall into bin 26. At the close of 10 seconds contacts AC are then opened and contacts A-B are closed. Assuming ice bin switch 45 is closed to signal the need for more ice, heater 44 will be energized to reset bimetal switch from cold contact F to warm contact E, whereby timer motor 53 is energized for an additional 10 seconds to rotate shaft 52 and mold striker 42 thereon out of mold-impacting position, and again to energize motor 24. While the motor 24 is energized and rotating, mold 22 contacts A- D are closed for 4 seconds to energize valve 47 and direct water through fill pipe 36 for flow into receptacle 27 to charge the mold cups 33. Bimetal switch 43 maintains warm contact E closed until water is frozen, whereupon contact E is opened and cold contact F closed, and timer contacts A-C are closed. The cycle is then repeated, provided that bin switch 45 is closed to signal the need for more ice.

I claim:

I. Apparatus for use in the cyclic production of individual ice masses, comprising: a plurality of concave mold members, mounted for movements between one position in which liquid introduced therein is frozen and another position accommodating harvesting of masses of frozen liquid, said mold members being positioned to face inwardly toward a common axis; means for centrifuging said mold members about said axis to hold liquid therein and to provide for movement of the members to said one position in which liquid so held is frozen; means for modifying the degree of centrifuging of said mold members to provide for movement of said members to said other position; and means for impacting said mold members sequentially upon movement of the latter to said other position to free said masses of frozen liquid from said mold members for harvesting.

2. Apparatus according to claim I, and characterized in that said axis is generally vertical and in that said mold members are pivotable in a substantially vertical plane in achievement of movements between their recited positions.

3. Apparatus according to claim 2, and further characterized in that said mold members are flexible and resilient, and the recited movements thereof further include flexure of said mold members.

4. Apparatus according to claim 3, and further characterized in that flexure of said mold members is accommodated by provision of a leaf spring extending across the open side of and affixed to opposed edge portions of said mold members, and further by the inclusion of a pivotal, cantilevered support arm affixed to a central region of said leaf spring.

5. Apparatus according to claim 1, and further characterized in that said last recited means for impacting said mold members comprises a generally cylindrical member extending transversely of the path of said mold members, said cylindrical member being rotatable about an axis spaced from and generally parallel to its major longitudinal axis and so positioned that a portion of said cylindrical member is movable into and out ofinterference relation with said mold members.

6. In ice making apparatus of the type including a plurality of concave flexible and resilient mold members having their concave portions presented toward a common axis, means for centrifuging said members to retain water therein as it is subjected to below-freezing temperatures, flexible and resilient means disposed and adapted to support said mold members from the regions of opposite rim portions thereof, in the recited axial orientation, and operable upon centrifuging of said members to provide both for vertical movements of said mold members and for movements of such rim portions toward one another substantially in the plane of rotation thereof, means operable to terminate the centrifuging and provide for deceleration of said distorted, vertically pivoted mold members, to accommodate movements of such rim portions away from one another and pivotation of said members to their normal rest positions, whereby ice masses may be stripped from the mold members, and means for impacting said mold members as the centrifuging thereof is tenninated.

7. Apparatus according to claim 6, and characterized in that said mold members are pivotable downwardly to rest position and upwardly to water freezing position.

8. ln centrifugal ice mold apparatus, a mold pocket comprising: a generally cup-shaped member of flexible and resilient material; leaf spring means extending generally diametrically across the open region of said member and affixed to the latter in the region of confronting edge portions thereof; a cantilever supported, pivotally mounted arm affixed to a generally central portion of said leaf spring means for sup porting said cup-shaped member in position such that its open region is movable between inclined and substantially vertical positions; and means operable to impact with said cup-shaped member upon movement thereof toward one of its last recited positions.

9. Apparatus according to claim 8, and further characterized in that said means operable to impact with said mold pocket upon movement thereof toward one of its recited positions comprises a generally cylindrical member extending transversely of said generally cup-shaped member and mounted for rotation about an axis so positioned that a portion of said cylindrical member is movable into and out of engagement with said cup-shaped member.

Claims (9)

1. Apparatus for use in the cyclic production of individual ice masses, comprising: a plurality of concave mold members, mounted for movements between one position in which liquid introduced therein is frozen and another position accommodating harvesting of masses of frozen liquid, said mold members being positioned to face inwardly toward a common axis; means for centrifuging said mold members about said axis to hold liquid therein and to provide for movement of the members to said one position in which liquid so held is frozen; means for modifying the degree of centrifuging of said mold members to provide for movement of said members to said other position; and means for impacting said mold members sequentially upon movement of the latter to said other position to free said masses of frozen liquid from said mold members fOr harvesting.

2. Apparatus according to claim 1, and characterized in that said axis is generally vertical and in that said mold members are pivotable in a substantially vertical plane in achievement of movements between their recited positions.

3. Apparatus according to claim 2, and further characterized in that said mold members are flexible and resilient, and the recited movements thereof further include flexure of said mold members.

4. Apparatus according to claim 3, and further characterized in that flexure of said mold members is accommodated by provision of a leaf spring extending across the open side of and affixed to opposed edge portions of said mold members, and further by the inclusion of a pivotal, cantilevered support arm affixed to a central region of said leaf spring.

5. Apparatus according to claim 1, and further characterized in that said last recited means for impacting said mold members comprises a generally cylindrical member extending transversely of the path of said mold members, said cylindrical member being rotatable about an axis spaced from and generally parallel to its major longitudinal axis and so positioned that a portion of said cylindrical member is movable into and out of interference relation with said mold members.

6. In ice making apparatus of the type including a plurality of concave flexible and resilient mold members having their concave portions presented toward a common axis, means for centrifuging said members to retain water therein as it is subjected to below-freezing temperatures, flexible and resilient means disposed and adapted to support said mold members from the regions of opposite rim portions thereof, in the recited axial orientation, and operable upon centrifuging of said members to provide both for vertical movements of said mold members and for movements of such rim portions toward one another substantially in the plane of rotation thereof, means operable to terminate the centrifuging and provide for deceleration of said distorted, vertically pivoted mold members, to accommodate movements of such rim portions away from one another and pivotation of said members to their normal rest positions, whereby ice masses may be stripped from the mold members, and means for impacting said mold members as the centrifuging thereof is terminated.

7. Apparatus according to claim 6, and characterized in that said mold members are pivotable downwardly to rest position and upwardly to water freezing position.

8. In centrifugal ice mold apparatus, a mold pocket comprising: a generally cup-shaped member of flexible and resilient material; leaf spring means extending generally diametrically across the open region of said member and affixed to the latter in the region of confronting edge portions thereof; a cantilever supported, pivotally mounted arm affixed to a generally central portion of said leaf spring means for supporting said cup-shaped member in position such that its open region is movable between inclined and substantially vertical positions; and means operable to impact with said cup-shaped member upon movement thereof toward one of its last recited positions.

9. Apparatus according to claim 8, and further characterized in that said means operable to impact with said mold pocket upon movement thereof toward one of its recited positions comprises a generally cylindrical member extending transversely of said generally cup-shaped member and mounted for rotation about an axis so positioned that a portion of said cylindrical member is movable into and out of engagement with said cup-shaped member.

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