Abstract: An arrangement for controlling the microwave power of magnetrons, in which a multiple of magnetrons are connected in parallel with a power unit (3) for generating a high magnetron-operating voltage, and which arrangement includes for each magnetron (1,2) a separate regulating circuit (9) which includes a current measuring circuit (10) for measuring the anode current passing through respective magnetrons, and in which arrangement the waveguides (70) to which the magnetrons are connected have earth potential. The invention is characterized in that the anode (4) of each magnetron (1, 2) is isolated electrically from the earth potential, in that the current measuring circuit (10) is connected between the anode (4) of the magnetron and the one terminal (23) of the power unit, and in that an over-voltage protector (78) is connected in parallel with the measuring circuit (10) for the purpose of limiting the voltage on the magnetron anode (4) in the event of a disruption in or failure of the measuring circuit (10).

Abstract: A method for controlling magnetrons with regard to their microwave power in those cases where a multiple of magnetrons are present. The method includes connecting two or more magnetrons in parallel with a power unit operative in generating a high voltage for operating the magnetron is connected to respective magnetrons and includes a current measuring circuit by which the anode current passing through respective magnetrons is measured on the high-voltage side of the magnetrons. The current measuring circuit is galvanically separated from a control circuit, which is arranged to control the anode current of a respective magnetron in response to a signal received from the current measuring circuit. Also an arrangement for carrying out the method.

Abstract: An arrangement for heating with the aid of microwave energy, comprising a microwave generator constructed to supply a waveguide, the waveguide having provided in one side surface thereof a dielectric plate through which microwave energy propagates. In accordance with the invention the arrangement includes at least two microwave generators (1, 2), each of which is arranged to supply a feed waveguide (3, 4). The feed waveguide (3, 4) is a power divider which is arranged to distribute the power input substantially equally to at least two applicators (7, 8; 9, 10) which extend at an angle to the feed waveguide, where each of the at least four applicators (7, 8; 9, 10) is provided on one side surface thereof with a dielectric plate (11, 12, 14) of the aforesaid kind. The applicators are positioned in relation to one another so that all dielectric plates (11, 12, 14) lie in one and the same plane.

Abstract: A cassette to be used in a conveyor device for products, for instance food stuff. The cassette (18) comprises a thin, broad-sided and broken through casing of substantially uniform thickness having an openable cover of broken through type. The casing and cover are interconnected along one side of the cover in several joints (47) and are interconnectable at several locking locations (48) along an opposite side of the cassette such that the casing and cassette in spite of the broken through structure, form a rigid and strong unit when the cover is closed.

Abstract: A continuous method for heating a product having at least one faster microwave heating portion and at least one slower microwave heating portion to a uniform predetermined temperature sufficient to sterilize the product without loss of odor, taste, texture, color or vitamin content quality by transporting the product through a plurality of microwave fields including a first higher energy field and one or more successively lower energy fields, in which the first microwave field is attenuated to an energy level sufficient to heat the fast microwave heating portions of the product to the predetermined temperature, the successively lower energy microwave fields are attenuated to an energy level sufficient to maintain the temperature of the faster heating portions and heat the slower heating portions to the predetermined temperature, and the transport of the product through the successively lower energy microwave fields is continued until the slower microwave heating portions of the product reach the predetermined

Abstract: A sluice device for insertion between zones having different environmental conditions, for instance pressure and/or temperature. A drum is rotatably arranged in an opening in a housing and has radially displaceable flaps uniformly distributed along the periphery of the drum. Each flap has a first portion for sealing against the housing, and a second portion of the flap, adjacent to the drum, cooperates with a sealing device. The sluice device is formed as a longitudinal groove which is open against the drum, whereby a longitudinal sealing member is arranged in the groove. The pressure difference between spaces at the two sides of the flap brings the longitudinal sealing member in such a sealing position that the flap, by the pressure difference, is placed in sealing abutment against the inside of the housing regardless of the positive or negative pressure difference.