This patent delivers microwave power and thermal power to the oven cavity simultaneously, thermal power being provided by a circulation of hot air forced through the cavity by a fan. When a predetermined maximum temperature of hot air is reached after a cold start, the oven automatically switches off or decreases in power to finish the cooking process.

American Patent #: 4,661,670
Australian Patent #: 573,412
Canadian Patent #: 1,249,036
Japanese Patent #: 2,539,194