Abstract: In the microwave oven of square waveguide type or coaxial tube type, the waveguide or inner conductor of the tube type is gradually declined from the inlet toward the outlet of the oven. A top slot is provided so that containers may be moved along the slot with their bottom portions being received in the oven and the contents heat sterilized. There is laid on a bottom surface of the oven a support rail for the bottoms of the containers, and this rail is gradually thickened from the inlet toward the outlet. More preferably, two or more such microwave ovens may be serially connected and the containers may be moved therethrough to heat sterilize medical fluids within each container in a stepwise manner.

Abstract: A rectangular waveguide is provided in communication with a microwave generator, and an irradiation furnace formed in its top wall with a slot is provided in communication with the rectangular waveguide. Ampules having only lower portions inserted through the slot into the irradiation furnace are transported by conveyor means along the slot. A depth of the irradiation furnace and/or a distance between the ampules and a surface of the slot may be adjusted to control sterilizing effect for medical fluid filling the ampule.

Abstract: A microwave heating device for using microwave energy to heat a high polymer material or the like being conveyed under pressure comprises a hollow, cylindrical microwave waveguide closed at one end and having a metallic shell capable of withstanding high internal pressures, a pressure partition made from a dielectric material provided within said waveguide near an open end thereof so as to define a sealed space between itself and the closed end of said waveguide and to define a path for introduction of microwaves between itself and the open end of said waveguide, a solid or liquid dielectric packing material filling said sealed space and thereby forming a packed dielectric region, said packing material having a lower specific inductive capacity than that of the material to be heated, a passage for pressurized conveyance of the material to be heated, said passage running transversely through said waveguide at said packed dielectric region thereof, and a microwave generator for transmitting microwaves into said