Griddle Plate Having a Vacuum Bonded Cook Surface

Abstract

A composite griddle plate comprising a first sheet of metal defining a cook surface and a core plate of a metal having a relatively high coefficient of heat conductivity wherein the first sheet remains in intimate contact with an upper surface of the core plate with the aid of a vacuum.

1 . A composite griddle plate for cooking food and adapted to be heated by an external source acting on a lower surface thereof, comprising at least a first sheet of metal defining a cook surface and a core plate of a metal having a relatively high coefficient of heat conductivity wherein the said first sheet remains in intimate contact with an upper surface of the core plate with the aid of a vacuum, and wherein the griddle plate is sealed around a perimeter thereof to maintain the vacuum, and wherein the first sheet of metal is thinner than the core plate to prevent thermal warpage during use. 
     
     
         2 . The griddle plate of  claim 1  wherein the core plate is made from a metal selected from the group consisting of aluminum and copper. 
     
     
         3 . The griddle plate of  claim 1  wherein the first sheet is one of stainless steel or titanium. 
     
     
         4 . The griddle plate of  claim 1  wherein the composite griddle plate is sealed around a perimeter thereof. 
     
     
         5 . The griddle plate of  claim 1  wherein the griddle plate is under a permanent vacuum. 
     
     
         6 . The griddle plate of  claim 1  wherein the griddle plate is under a continuous vacuum selectively applied by a vacuum pump during use. 
     
     
         7 . The griddle plate of  claim 1  wherein the seal is provided by welding. 
     
     
         8 . A composite griddle plate for cooking comprising a high heat conductivity core plate selected from aluminum or copper, upper and lower sheets of metal facing said core plate, said upper sheet selected from one of stainless steel or titanium, said griddle plate having a perimeter sealed by welding and defining an interior that is under a permanent vacuum whereby said upper and lower sheets remain in intimate contact with the high heat conductivity core plate by virtue of said vacuum and wherein said upper and lower sheets of metal are thinner than the core plate to prevent thermal warpage during use. 
     
     
         9 . The griddle plate of  claim 8  wherein the upper and lower sheets are stainless steel. 
     
     
         10 . The griddle plate of  claim 8  wherein the upper sheet is titanium and the lower sheet is stainless steel. 
     
     
         11 . The griddle plate of  claim 8  wherein the lower sheet is a ferromagnetic material to permit heating of the griddle plate by induction.