Abstract: In certain examples, a food processing machine for processing a food product includes a housing defining a cavity, a conveyor with a belt comprising metal for conveying the food product through the cavity in a longitudinal direction, and a convection heating system for heating air in the cavity such that heated air heats the food product as the food product is conveyed through the cavity. A microwave launch box system is configured to emit microwave energy into the cavity in a lateral direction transverse to the longitudinal direction to thereby further heat the food product as the food product is conveyed through the cavity.

Abstract: In certain examples, a food processing machine for processing a food product includes a housing defining a cavity, a conveyor with a belt comprising metal for conveying the food product through the cavity in a longitudinal direction, and a convection heating system for heating air in the cavity such that heated air heats the food product as the food product is conveyed through the cavity. A microwave launch box system is configured to emit microwave energy into the cavity in a lateral direction transverse to the longitudinal direction to thereby further heat the food product as the food product is conveyed through the cavity.

Abstract: In certain examples, a food processing machine for processing a food product includes a housing defining a cavity, a conveyor with a belt comprising metal for conveying the food product through the cavity in a longitudinal direction, and a convection heating system for heating air in the cavity such that heated air heats the food product as the food product is conveyed through the cavity. A microwave launch box system is configured to emit microwave energy into the cavity in a lateral direction transverse to the longitudinal direction to thereby further heat the food product as the food product is conveyed through the cavity.

Abstract: In certain examples, a food processing machine for processing a food product includes a housing defining a cavity, a conveyor with a belt comprising metal for conveying the food product through the cavity in a longitudinal direction, and a convection heating system for heating air in the cavity such that heated air heats the food product as the food product is conveyed through the cavity. A microwave launch box system is configured to emit microwave energy into the cavity in a lateral direction transverse to the longitudinal direction to thereby further heat the food product as the food product is conveyed through the cavity.

Abstract: The oven cavity (1) of a microwave oven includes an apertured launch wall (3) on the external side of which a launch box (5) is mounted so as to cover the aperture. Two three or four magnetrons supply microwave energy to the launch box (5), and hence into the oven cavity, via corresponding waveguides (10a, 10b, 10c) each in communication with a respective side of the launch box (5). In another aspect of the invention, a microwave oven cavity (1) includes an apertured launch wall (3), means for supplying microwave energy to the cavity (1) through the aperture and a match plate (26) mounted in the cavity so as to be spaced a small distance from the launch wall (3) and in registration with the aperture. The match plate and the launch wall (3), define a slot for coupling microwave energy into the cavity (1), and at least one hole (27) in the match plate (26), in use, enables microwave energy to be coupled to resonant modes in the centre of the cavity.

Abstract: A microwave oven comprises a magnetron for delivering microwave power to a cavity of the oven, a rotatable phase modular (19) an electrical resistance heating element (12) and a rotatable fan (20) for forcing air over the resistance heating element (12) and though the cavity. The phase modulator (19) and the fan (20) are mounted on a common driveshaft (18). A matchplate (9) is mounted in the cavity.

Abstract: A microwave oven has an oven cavity in which a launch site for delivering microwave energy into the oven cavity is provided by a hole (6) in a wall (2) of the cavity and a match plate (10). In order to improve the distribution of microwave energy in the cavity, the oven also has a second wall (4) partially covered on its internal side by a second match plate (30) which acts as a second resonator. The second wall may include a hole which, with the second match plate, forms a second launch site for delivering microwave energy into the oven cavity, in which case the two holes are interconnected by a waveguide via which said microwave energy is supplied from at least one magnetron.

Abstract: A microwave oven has an oven cavity in which a launch site for delivering microwave energy into the oven cavity is provided by a hole (6) in a wall (2) of the cavity and a match plate (10). In order to improve the distribution of microwave energy in the cavity, the oven also has a second wall (4) partially covered on its internal side by a second match plate (30) which acts as a second resonator. The second wall may include a hole which, with the second match plate, forms a second launch site for delivering microwave energy into the oven cavity, in which case the two holes are interconnected by a waveguide via which said microwave energy is supplied from at least one magnetron.

Abstract: A microwave oven has an oven cavity with a wall (2) formed with a hole (6) covered on an external side of the wall by a metal launch box (8) and choke plate (7). A metal match plate (10) is mounted on the internal side of the wall (2) so that the match plate (10) and the launch box (8) form a launch cavity for delivering microwave energy to the cavity. The choke plate (7) has a peripheral choke channel which prevents leakage of microwave energy between the launch box (8) and choke plate (7), enabling the choke plate (7) and match plate (10) to be bolted to the wall (2).

Abstract: A microwave oven has an oven cavity with a wall (2) formed with a hole (6) covered on an external side of the wall by a metal launch box (8) and choke plate (7). A metal match plate (10) is mounted on the internal side of the wall (2) so that the match plate (10) and the launch box (8) form a launch cavity for delivering microwave energy to the cavity. The choke plate (7) has a peripheral choke channel which prevents leakage of microwave energy between the launch box (8) and choke plate (7), enabling the choke plate (7) and match plate (10) to be bolted to the wall (2).

Abstract: A microwave oven has a food-receiving cavity and a magnetron for delivering microwave power to the cavity. The magnetron is supplied with a high voltage through a transformer, and a variable impedance is connected in series with the primary winding of the transformer. The resistive heating effect produced by primary current is utilized to heat the air in the oven cavity, and the magnitude of the impedance is variable to vary the output of the magnetron.