Oven with refrigerated food storage based on thermal exchange fluid

• US 4,156,454 A
• Filed: 04/29/1977
• Issued: 05/29/1979
• Est. Priority Date: 10/04/1972
• Status: Expired due to Term

• Current Assignee: Stephen F. Skala
• Original Assignee: Stephen F. Skala
• Inventors: Skala, Stephen F.
• Primary Examiner(s): Myhre, Charles J.
• Assistant Examiner(s): LaTulin, Margaret
• Application Number:
  US05/792,455
• Time in Patent Office: 760 Days
• Field of Search: 165/2, 165/12, 165/14, 165/18, 165/26, 165/50, 165/61, 165/17, 99/326, 99/332, 62/185, 62/234, 62/376, 62/434, 62/435, 62/451, 62/82, 62/282
• US Class Current: 165/259
• CPC Class Codes: A47J 27/17 with steam jacket
• CPC Class Codes: A47J 37/00 Baking; Roasting; Grilling; Frying bakers' ovens, non-domestic baking apparatus or equipment A21B; domestic stoves or ranges F24B, F24C
• CPC Class Codes: F25D 17/02 for circulating liquids, e.g. brine
• CPC Class Codes: F25D 31/005 Combined cooling and heating devices
• CPC Class Codes: Y10S 165/918 Heated and cooled food cabinets and/or trays

Abstract

An oven, which maintains food at a low temperature to preserve its properties for subsequent unattended cooking at high oven temperatures, is cooled and heated by a flowing liquid thermal exchange fluid which is cooled and heated by flowing through thermal sources separate from the oven. Within a food processing compartment of the oven, heat is exchanged between an enclosed chamber heat exchanger and the food by air convection.

In a preferred embodiment, the oven is one of a plurality of domestic appliances similarly heated and cooled by a liquid thermal exchange fluid. The oven and the other appliances share in common an assembly of thermal reservoirs which provides thermal exchange fluid under pressure at substantially the temperatures of the thermal reservoirs which include a hot and a cold reservoir. The oven controls heating and cooling of the food processing compartment by positioning selector valves which admit thermal exchange fluid from one of the thermal reservoirs and by adjusting a regulator valve to control flow through the enclosed chamber. The selector and regulator valves are controlled in response to a computer and a temperature sensor to attain predetermined temperature levels in the food processing compartment which include cold to preserve food properties and hot to desirably alter the food properties.

Claims

1. A method for refrigerating food in an oven for subsequent cooking, said oven having a food processing compartment and a single enclosed chamber in said food processing compartment, said enclosed chamber receiving a single substance liquid thermal exchange fluid at hot and cold temperatures comprising the steps of

placing food in the food storage compartment separate from the enclosed chamber,

cooling the thermal exchange fluid by a cold source separate from the oven,

causing the cold thermal exchange fluid to flow through the enclosed chamber to thereby cool the food processing compartment for a predetermined time to preserve properties of the food,

stopping flow of the cold thermal exchange fluid through the enclosed chamber,

heating the thermal exchange fluid to a hot oven temperature by a hot source separate from the oven,

causing the hot thermal exchange fluid to flow through the enclosed chamber for a predetermined time to thereby heat the food processing compartment to cook the food by desirably and nonreversibly altering properties of the food by thermal processes, said enclosed chamber exchanging heat with said food by gases moving within the food storage compartment between the enclosed chamber and the food.

2. The method of claim 1 wherein said hot oven temperature exceeds 275°

F.

3. The method of claim 1 wherein temperature of the food storage compartment is controlled by regulating flow of the thermal exchange fluid through the enclosed chamber.

4. The method of claim 3 wherein the steps of causing cold and hot thermal exchange fluid to flow through the enclosed chamber include operating selector valves in response to temperature set points to connect the enclosed chamber alternately to a source of cold thermal exchange fluid under a differential pressure and to a source of hot thermal exchange fluid under a differential pressure.

5. Apparatus for storing food at low temperature to preserve properties of the food and for processing the food at high oven temperature to cook the food comprising

a thermally insulated food processing compartment,

single enclosed chamber within the food processing compartment for exchanging heat therewith, said enclosed chamber receiving a liquid thermal exchange fluid, said thermal exchange fluid being a single substance varying in temperature,

means separate from the food processing compartment to cool the thermal exchange fluid to provide a body of cold thermal exchange fluid,

means to deliver the body of cold thermal exchange fluid under pressure to the enclosed chamber,

means separate from the food processing compartment to heat the thermal exchange fluid to a hot oven temperature to provide a body of hot thermal exchange fluid,

means to deliver the body of hot thermal exchange fluid under pressure to the enclosed chamber,

means to select the body of cold thermal exchange fluid or flow through the enclosed chamber to cool the food processing compartment for a predetermined time thereby preserving the properties of food contained therein,

means to stop flow of the body of cold thermal exchange fluid through the enclosed chamber,

means to select the body of hot thermal exchange fluid for flow through the enclosed chamber to heat the food processing compartment for a predetermined time thereby cooking the food contained therein,

means to stop flow of the body of hot thermal exchange fluid through the enclosed chamber,

means to support the food in the food processing compartment separate from the enclosed chamber, said food heated and cooled by gases moving within the food processing compartment.

6. The apparatus of claim 5 wherein flow of said hot and cold thermal exchange fluid through the enclosed chamber is regulated by means responsive to temperature within the food processing compartment to regulate temperature therein to predetermined levels.

7. The apparatus of claim 5 wherein said means to heat the thermal exchange fluid heats the body of hot thermal exchange fluid to temperatures exceeding 275°

F.

8. The method of claim 7 wherein said altering of properties of the food includes browning of surfaces of the food.

9. The method of claim 8 wherein the cooking comprises roasting and baking.