Thermally Actuated Turntable for Conventional/Convection Cooking Ovens

Abstract

The present invention is a thermally actuated turntable suitable for conventional and convection cooking ovens, which posses uneven temperature/cooking characteristics. By means of coupling dissimilar materials, each having a wide variance in their respective coefficients of thermal expansion, the relative linear expansion of these materials caused by the ambient heat found in the cooking chamber of an oven can be utilized in such a way as to create a thermo-linear motor and thus produce relatively small linear displacements of the actuator with relatively high force capabilities. This linear displacement can then be magnified by means of the mechanical advantage of levers to produce sufficient linear displacement of a rack and pinion gear set which is capable of producing multiple rotations of an attached platter during a typical short duration cooking cycle. This slow speed rotational motion is very advantageous for cooking short duration food items.

1 . A turntable for conventional and convection ovens, the turntable comprising:
 a. at least one thermally responsive actuator;   b. a linkage system, further comprising at least one lever, operationally connected to the thermally responsive actuator;   c. a drive mechanism operationally coupled to the linkage system and further comprising a rack and pinion gear set; and   d. a turntable platter coupled to the drive mechanism;   wherein the thermally responsive actuator changes shape while exposed to ambient heat within an oven chamber and moves the linkage system and the associated drive mechanism, thereby rotating the turntable platter.   
     
     
         2 . The turntable of  claim 1 , the at least one thermally responsive actuator comprising at least two different materials with unequal coefficients of thermal expansion. 
     
     
         3 . The turntable of  claim 2 , the at least one thermally responsive actuator being comprised of an aluminum tube with a coaxial rod of 64FeNi coupled thereto on one end. 
     
     
         4 . The turntable of  claim 1 , further comprising a covering providing a thermally isolated interior in which the thermally responsive actuator resides. 
     
     
         5 . The turntable of  claim 4  the covering further comprising at least one user selectable vent. 
     
     
         6 . The turntable of  claim 1 , comprising at least two thermally responsive actuators, the actuators being linked in a manner such that their responses to change in ambient temperature co-operate. 
     
     
         7 . The turntable of  claim 6 , the thermally responsive actuators being comprised of at least two different materials with unequal coefficients of thermal expansion. 
     
     
         8 . The turntable of  claim 7 , at least one of the thermally responsive actuators being comprised of an aluminum tube with a coaxial rod of 64FeNi coupled thereto on one end.