MICROWAVE TURNTABLE CONVECTION HEATER

摘要

A method and apparatus for heating or cooling a product (P) which includes a plurality of tapered ducts (90a, 90b) in a cabinet (20) above and below a turntable (16) to form streams which are directed toward the product (P). Spent air is drawn through intake openings (83, 87) in return ducts (80a, 80b) in the cabinet. Temperature controlled gas is delivered at an angle through an array of openings adjacent opposite edges of an opening through which a product is loaded on the turntable (16) in a loading zone to cause most of the heated air to be drawn to return duct openings and to maintain internal pressure in the baking zone (10) in the cabinet to prevent ingress and egress of air through the loading opening (35). Orifices (94) are formed in a circular array of rings (94a-94h) such that the sum of the areas of orifices in each ring spaced from the axis about which the turntable rotates is substantially equal.