Abstract The invention in different forms is shown as a serpentine antenna embedded in a microwave-transparent plate, nested in one surface of such a plate, and deposited on one surface of such a plate. A pair of such plate-antenna structures are mounted in the top and bottom of an oven cavity. The center of each antenna has an integral probe extending through openings in the back wall of the cavity and into the arms of a waveguide T. Energy from a magnetron is injected into the leg of the T, and divides between the arms to excite the antennas which then radiate microwave energy into the cavity. The material of the plates serves to absorb some microwave energy, whereby to present a desired minimum load to the magnetron when it is operating while the cavity is empty. The actual oven enclosure for cleaning purposes is that defined by the plates and the portions of the walls and door between the plates. These surfaces are flat, whereby they can quickly be cleaned with a minimum of effort.
The combination, for a microwave oven, of: a plate to be placed in the oven; and an antenna element integral with said plate; said antenna element having an integral portion adapted to couple energy thereto from an external source to cause said element to radiate microwave energy into the oven; and said plate being operable to permit radiation of energy from said element while absorbing a predetermined amount thereof, whereby to present a minimum load for the external source.
Claim 2
Dependent Claim
79 words
The combination, for a microwave oven, of: a plate to be placed in the oven; and an antenna element integral with said plate; said antenna element having an integral portion adapted to couple energy thereto from an external source to cause said element to radiate microwave energy into the oven; and said plate being operable to permit radiation of energy from said element while absorbing a predetermined amount thereof, whereby to present a minimum load for the external source.
Claim 3
Dependent Claim
13 words
The combination of claim 1, wherein said element is embedded in said plate.
Claim 4
Dependent Claim
15 words
The combination of claim 1, wherein said element is on one surface of said plate.
Claim 5
Dependent Claim
16 words
The combination of claim 1, wherein said element is nested in one surface of said plate.
Claim 6
Dependent Claim
85 words
The combination of claim 1, including: a microwave oven having a metal cavity and a door through which to place foodstuff in the cavity; and a pair of spaced plates as defined in claim 1 being positioned in said oven adjacent opposite walls of said cavity; said plates being arranged so as to prevent materials from collecting between their edges and the surrounding walls of the cavity; and said plates forming opposed walls of an enclosure within the cavity for the foodstuff to be cooked.
Claim 7
Dependent Claim
22 words
The combination of claim 5, wherein said plates are horizontal and are positioned adjacent the top and bottom walls of the cavity.
Claim 8
Dependent Claim
44 words
The combination of claim 6, wherein the top plate and the top cavity wall have a plurality of aligned openings through which to permit vapors to escape from said cavity; said openings being dimensioned to prevent the escape of microwave energy from said cavity.