Ice making machine, method and evaporator assemblies

• US 20070130983A1
• Filed: 10/04/2006
• Published: 06/14/2007
• Est. Priority Date: 10/05/2005
• Status: Active Grant

• Current Assignee: Mile High Equipment Co. (Ali Holding Srl)
• Original Assignee: Enodis Corporation (Ali Holding Srl)
• Inventors: Allison, Matthew, Broadbent, John
• Granted Patent: US 7,540,161 B2
• Time in Patent Office: Days
• US Class Current: 62/351
• CPC Class Codes: F25B 39/02 Evaporators
• CPC Class Codes: F25C 1/12 by freezing water on cooled surfaces, e.g. to form slabs
• CPC Class Codes: F25C 2400/02 Freezing surface state
• CPC Class Codes: F25C 2600/04 Control means
• CPC Class Codes: F25C 5/08 by heating bodies in contact with the ice

Abstract

Ice making machine that uses PETD harvest technology, evaporators, ice molds and cooling system. One evaporator makes thin layers of ice that are laminated to form a larger ice piece. Other evaporators include an ice forming surface on a material that has good thermal conductivity for forming ice in a freeze mode and good electrical conductivity to serve as a resistive heater during a harvest mode. One evaporator has a plate and an array of freezing sites that extend above a surface thereof. Another evaporator has a plate that is divided into strips of good and poor thermal conductivity by. Another evaporator has a refrigerant tube that is sandwiched between a pair of corrugated sheets that have ice forming surfaces. Another evaporator has a waffle style pan that is constructed of a dielectric layer sandwiched between a pair of copper layers. Another evaporator forms an ice slab on an inclined flat surface, which after harvest is diced into cubes with a wire grid. A cooling system uses an evaporator to provide a cooling air to an ice mold to form ice and uses PETD energy to harvest the ice and defrost the evaporator.

Claims

1. An ice making machine comprising:

a water supply, a cooling system, an electrical energy source and an evaporator assembly, wherein said evaporator assembly comprises at least one thermally conductive surface disposed in thermal transfer with an electrically conductive and thermally conductive layer, and wherein said layer is connected in circuit with said electrical energy source; and

a controller that during a freeze mode operates said water supply and said cooling system to form ice on said electrically conductive and thermally conductive layer and during a harvest mode operates said electrical energy source to apply electrical pulse energy to said electrically conductive and thermally conductive layer to melt an interfacial layer of said ice such that it is freed from said layer.

2. The ice making machine of claim 1, wherein said electrically conductive and thermally conductive layer is made of a material selected from the group consisting of:

aluminum, steel, copper and thermally conductive plastic.

3. The ice making machine of claim 1, wherein said electrically conductive and thermally conductive layer is a foil.

4. The ice making machine of claim 1, wherein said thermally conductive surface is part of an array of thermally conductive surfaces.

5. The ice making machine of claim 4, wherein said freed ice comprises a plurality of thin ice layers, wherein said evaporator assembly further comprises a laminator that combines said ice layers into a laminated ice piece.

6. The ice making machine of claim 4, wherein said evaporator assembly further comprises a base portion that includes said array of thermally conductive surfaces, and wherein said thermally conductive surfaces are separated from one another by spaces over which ice is not formed during said freeze mode.

7. The ice making machine of claim 6, wherein said spaces are occupied by a substance selected from the group consisting of:

air and a thermally insulating material.

8. The ice making machine of claim 6, wherein said base portion comprises a plate that includes a plurality of raised portions that extend in rows across said plate and at least one layer of poor thermal conductivity that extends over said rows to occupy said spaces.

9. The ice making machine of claim 8, wherein said raised portions comprise raised freeze sites that form said array of surfaces.

10. The ice making machine of claim 9, wherein said array of thermally conductive surfaces is disposed on triangular shaped ridges of said raised portions.

11. The ice making machine of claim 4, wherein said evaporator assembly further comprises a base portion that includes a plurality of corrugations interleaved with flat portions that form said array of thermally conductive surfaces.

12. The ice making machine of claim 6, wherein a layer of dielectric material is disposed between said base portion and said electrically conductive and thermally conductive layer.

13. The ice making machine of claim 6, wherein said base portion is configured as a pan.

14. The ice making machine of claim 1, wherein said thermally conductive surface is substantially flat, wherein said ice is formed as a slab, and wherein said freed slab of ice is partitioned into smaller pieces of ice.

15. The ice making machine of claim 14, wherein said evaporator assembly further comprises a wire grid that is used to partition said freed slab of ice into said pieces of ice.

16. The ice making machine of claim 1, wherein said cooling system is selected from the group consisting of:

refrigerant and cool air.

17. The ice making machine of claim 1, wherein said cooling system comprises a blower, a refrigerant supply, and an evaporator;

and

wherein the controller during the freeze mode operates said blower to provide an air stream that flows to said evaporator assembly and operates said refrigerant supply and said evaporator to cool said air stream to a temperature that causes said ice to form on said electrically conductive and thermally conductive layer.

18. An ice making machine comprising:

a water supply, a cooling system and an ice mold, wherein said cooling system comprises a blower, a refrigerant supply, and an evaporator; and

a controller that during a freeze mode operates said water supply and said cooling system to form ice on a surface of said ice mold by operating said blower to provide an air stream that flows to said ice mold and operates said refrigerant supply and said evaporator to cool said air stream to a temperature that causes water from said water supply to form ice on said surface of said ice mold.

19. The ice making machine of claim 18, further comprising an electrical energy source, wherein said controller during a harvest mode operates said electrical energy source to provide electrical pulse energy to heat said ice mold so as to melt an interfacial layer of said ice such that it is freed from said surface of said ice mold.

20. The ice making machine of claim 18, further comprising an electrical energy source, wherein said controller defrosts said evaporator by operating said electrical energy source to provide electrical pulse energy to heat said evaporator.

21. An evaporator assembly comprising:

at least one thermally conductive surface disposed in thermal transfer with an electrically conductive and thermally conductive layer, and at least one electrical connection affixed to said electrically conductive and thermally conductive layer.

22. The evaporator assembly of claim 21, wherein said electrically conductive and thermally conductive layer is made of a material selected from the group consisting of:

aluminum, steel, copper and thermally conductive plastic.

23. The evaporator assembly of claim 21, wherein said electrically conductive and thermally conductive layer is a foil.

24. The evaporator assembly of claim 21, wherein said thermally conductive surface is part of an array of thermally conductive surfaces.

25. The evaporator assembly of claim 24, wherein said ice, when freed of said surfaces, comprises a plurality of thin ice layers, and further comprising a laminator that combines said ice layers into a laminated ice piece.

26. The evaporator assembly of claim 24, further comprising a base portion that includes said array of thermally conductive surfaces, and wherein said thermally conductive surfaces are separated from one another by spaces over which ice is not formed during a freeze mode.

27. The evaporator assembly of claim 26, wherein said spaces are occupied by a substance selected from the group consisting of:

air and a thermally insulating material.

28. The evaporator assembly of claim 26, wherein said base portion comprises a plate that includes a plurality of raised portions that extend in rows across said plate and at least one layer of poor thermal conductivity that extends over said rows to occupy said spaces.

29. The evaporator assembly of claim 28, wherein said raised portions comprise raised freeze sites that form said array of surfaces.

30. The evaporator assembly of claim 29, wherein said array of thermally conductive surfaces is disposed on triangular shaped ridges of said raised portions.

31. The evaporator assembly of claim 26, further comprising a base portion that includes a plurality of corrugations interleaved with flat portions that comprise said array of thermally conductive surfaces.

32. The evaporator assembly of claim 28, wherein a layer of dielectric material is disposed between said base portion and said electrically conductive and thermally conductive layer.

33. The evaporator assembly of claim 24, wherein said array of thermally conductive surfaces is configured in a pan.

34. The evaporator assembly of claim 21, wherein said thermally conductive surface is substantially flat and ice formed thereon is a slab.

35. The evaporator assembly of claim 34, further comprising a wire grid that partitions said slab of ice, when freed from said electrically conductive and thermally conductive layer, into smaller pieces of ice.

36. An evaporator assembly comprising:

a plate comprising a plurality of raised portions that extend in rows across said plate and at least one layer of poor thermal conductivity that extends over said rows and shaped to partition each of said rows into a plurality of freeze sites, and at least one electrical connection affixed to said plate.

37. The evaporator assembly of claim 36, further comprising at least one refrigerant passage disposed in said plate.

38. An evaporator assembly comprising:

a refrigerant tube and a plate comprising a plurality of corrugations interleaved with flat portions that are bonded to said refrigerant tube, and at least one electrical connection affixed to said plate.

39. The evaporator assembly of claim 38, wherein said corrugations and flat portions are disposed vertically.

40. The evaporator assembly of claim 38, wherein said plate is constructed of a layer of dielectric material sandwiched between first and second metallic layers.

41. An evaporator assembly comprising:

a metallic pan having a plurality of rows of freeze sites and a refrigerant tube disposed in thermal contact with said freeze sites, and at least one electrical connection affixed to said pan.

42. The evaporator assembly of claim 41, wherein said pan is a composite constructed of a dielectric layer sandwiched between first and second metallic layers.

43. The evaporator assembly of claim 41, wherein said composite is coated with nickel.

44. An evaporator assembly comprising:

a substantially flat electrically conductive and thermally conductive plate that has a substantially flat surface that is slightly inclined with a downward slope, and at least one electrical connection affixed to said pan.

45. The evaporator assembly of claim 44, further comprising a wire grid disposed to collect a slab of ice freed from said surface during a harvest mode and to partition said slab of ice into smaller pieces of ice.

46. A method of making ice with an ice making machine that comprises an evaporator assembly that includes at least one thermally conductive surface in thermal transfer with an electrically conductive and thermally conductive layer, a water supply, a cooling system and an electrical energy source, comprising:

during a freeze mode operating said water supply and said cooling system to form ice on said electrically conductive and thermally conductive layer; and

during a harvest mode operating said electrical energy source to apply electrical pulse energy to said electrically conductive and thermally conductive layer to melt an interfacial layer of said ice such that it is free from said electrically conductive and thermally conductive layer.

47. The method of claim 46, wherein said freed ice comprises a plurality of thin ice layers, and further comprising laminating said thin ice layers into a laminated ice piece.

48. The method of claim 46, wherein said thermally conductive surface is part of an array of thermally conductive surfaces in thermal transfer with said electrically conductive and thermally conductive layer, wherein said evaporator assembly further includes a plate that includes a plurality of raised portions that extend in rows across said plate and at least one layer of poor thermal conductivity that extends over said rows to partition said rows into said array of thermally conductive surfaces.

49. The method of claim 46, wherein said thermally conductive surface is part of an array of thermally conductive surfaces in thermal transfer with said electrically conductive and thermally conductive layer, wherein said evaporator assembly further comprises a plate that includes a plurality of corrugations interleaved with flat portions that form said array of thermally conductive surfaces.

50. The method of claim 46, wherein said thermally conductive surface is part of an array of thermally conductive surfaces in thermal transfer with said electrically conductive and thermally conductive layer, wherein said evaporator assembly further comprises a pan.

51. The method of claim 46, wherein said thermally conductive surface is substantially flat and ice formed thereon is a slab, and further comprising partitioning said slab of ice, when freed from said electrically conductive and thermally conductive layer, into a plurality of smaller pieces of ice.