153results about "Multi-cavity magnetrons" patented technology

The present invention provides a relativistic magnetron with axial extraction, or magnetron with diffraction output (MDO), with a mode converter placed directly within the diffraction output of radiation to effectively convert the operating π-mode into a radiated mode of simpler radiation patterns.

A magnetron comprising an anode portion having an anode cylinder and vanes, a cathode portion having a coil-shaped filament, magnetic poles disposed at the upper and lower ends of the filament, ring-shaped permanent magnets made of a Sr ferrite magnet containing La-Co, an input portion and an output portion. The diameter phia of the inscribed circle at the ends of the vanes constituting the anode portion is in the range of 7.5 to 8.5 mm, and the outside diameter phic of the coil-shaped filament 1 constituting the cathode portion is in the range of 3.4 to 3.6 mm.

A high-power microwave generator employing a plurality of inexpensive commercial magnetron tubes cross-coupled by means of a secondary coupling path between each magnetron output pair, whereby a portion of the output energy from a first magnetron tube is injected into a second magnetron tube and a portion of the output energy from the second magnetron tube is similarly injected into the first magnetron tube. The resulting cross-injection of microwave energies brings the respective magnetron tube pair into a phase-lock sufficiently stable to permit coherent combination of their outputs for many high-power microwave applications, such as directed energy weapon systems. The magnetron phase-locking system requires no external components other than the secondary coupling paths of this invention.

An electromagnetic radiation source is disclosed. The electromagnetic radiation source includes an anode having a first conductor, a second conductor positioned relative to the first conductor, a plurality of pole pieces coupled to at least one of the first conductor and the second, and at least one mechanical phase reversal positioned along the first conductor or second conductor. Adjacent pole pieces are separated by a gap. The electromagnetic radiation source also includes a cathode separated from the anode by an anode-cathode space, electrical contacts for applying a dc voltage between the anode and the cathode and establishing an electric field across the anode-cathode space, and at least one magnet arranged to provide a dc magnetic field within the anode-cathode space generally normal to the electric field. Electrons emitted from the cathode are influenced by the electric and magnetic fields to follow a path through the anode-cathode space and pass in close proximity to the plurality of pole pieces, and the gaps between adjacent pole pieces provide fringing fields which interact with the electrons to produce single mode operation at a desired operating frequency.

A magnetron for a microwave oven includes a yoke, an anode cylindrical body installed inside the yoke, a plurality of veins mounted inside the anode cylindrical body, a filament installed in a center of the veins, and an upper magnet and a lower magnet respectively mounted on an upper side and a lower side of the anode cylindrical body. The magnetron also includes an upper pole piece and a lower pole piece respectively installed between the anode cylindrical body and the upper and lower magnets. A length (L) from an external tip of a central part of the upper pole piece to an internal tip thereof, on which a hollow part is formed, is adjusted to suppress harmonics in the magnetron. Thus, generation of the harmonics may be effectively attenuated, and an output of a microwave may be enhanced by preventing power consumption of the magnetron which may be large due to interrupting harmonics.

Embodiments of the present invention generally provide a magnetron that is encapsulated by a material that is tolerant of heat and water. In one embodiment, the entire magnetron is encapsulated. In another embodiment, the magnetron includes magnetic pole pieces, and the magnetic pole pieces are not covered by the encapsulating material.

A magnetron of improved performance capable of stabilizing the frequency and phase of magnetron output for use in particle accelerators and other applications. Thin variable-permeability blocks are attached inside the resonant anode structures of a standard magnetron design. A variable bias electromagnet, with field orthogonal in direction to the RF magnetic field, is used to vary the permeability of each block and therefore the resonant frequency of each anode structure. An electronic feedback control circuit adjusts the bias magnetic fields to lock in the frequency and phase of the magnetron output to an external low-level reference signal. Such devices may be used to provide synchronized high-power RF to many locations (e.g. the RF cavities of a particle accelerator), while requiring the distribution only of electrical power and an appropriate low-level RF reference signal.

A magnetron in accordance with the present invention is configured so that an antenna lead (17) connected to a desired position of an anode segment (2) passes through a magnetic pole piece (7) and a metal cylinder (8) so as not to make contact therewith and is connected to the output portion (20) of the magnetron, and so that the electrical length L1 of this antenna lead (17) between the opening end of a third harmonic restraint choke (15) and the connection portion of the anode segment (2) is 1 / 2 of the wavelength (lambda) of the third harmonic, thereby restraining the third harmonic and the side bands of the third harmonic.

At an oscillation frequency of 2450 MHz band, number of the vanes constituting the anode part of the magnetron being, the diameter 2ra of the circle inscribing tip portions of the vanes on the cathode side being 8.0 to 8.8 mm, the diameter 2rc of the outer periphery of the filament constituting the cathode part being 3.5 to 3.9 mm, the height A3 of the vane in the direction of the tube axis is 7.0 to 8.0 mm, the mutual distance A1 between the bases of the pair of funnel-shaped pole pieces fixed to both sides of the anode part being 21.5 to 23.5 mm, the mutual distance A2 between the bottom portions of the pair of pole pieces being 10.2 to 11.2 mm, the inner diameter P1 of the through-hole of the pole piece being 8.3 to 8.5 mm, and the outer diameter P2 of the bottom portion being 11.0 to 16.0 mm are set up.

A magnetron includes a ring-shaped anode, a cathode, an activating space, at least one permanent magnet and a magnetic flux carrying unit. The ring-shaped anode forms a plurality of resonance circuits. The cathode is disposed at the axial center of the anode to emit thermions. The activating space is formed between the anode and the cathode. The at least one permanent magnet is provided beside the anode. The magnetic flux carrying unit carries magnetic flux generated by the at least one permanent magnet to the activating space. A microwave oven and / or high frequency heating apparatus may utilize the magnetron.

At an oscillation frequency of 2450 MHz band, number of the vanes constituting the anode part of the magnetron being, the diameter 2 ra of the circle inscribing tip portions of the vanes on the cathode side being 8.0 to 8.8 mm, the diameter 2 rc of the outer periphery of the filament constituting the cathode part being 3.5 to 3.9 mm, the height A 3 of the vane in the direction of the tube axis is 7.0 to 8.0 mm, the mutual distance A 1 between the bases of the pair of funnel-shaped pole pieces fixed to both sides of the anode part being 21.5 to 23.5 mm, the mutual distance A 2 between the bottom portions of the pair of pole pieces being 10.2 to 11.2 mm, the inner diameter P 1 of the through-hole of the pole piece being 8.3 to 8.5 mm, and the outer diameter P 2 of the bottom portion being 11.0 to 16.0 mm are set up.

Disclosed herein is a magnetron. The magnetron comprises an anode cylinder, upper and lower magnets provided to upper and lower portions of the anode cylinder, and upper and lower magnetic poles connected to the magnets, respectively. Each of the magnets has an inner diameter of 19˜21 mm, a thickness of 11.5˜12.5 mm, and an outer diameter of 50˜54 mm.

A crossed field device, such as a magnetron or crossed field amplifier, that includes a cathode, an anode, one or more magnetic elements, and one or more extraction elements. In one embodiment, the crossed field device includes an annular cathode and anode that are axially spaced from one another such that the device produces an axial electric (E) field and a radial magnetic (B) field. In another embodiment, the crossed field device includes an oval-shaped cathode and anode that are radially spaced from one another such that the device produces a radial electric (E) field and an axial magnetic (B) field. The crossed field device may produce electromagnetic (EM) emissions having a frequency ranging from megahertz (MHz) to terahertz (THz), and may be used in one of a number of different applications.

A magnetron is provided including a yoke having an inner space; a first magnet provided at one end of the inner space, a second magnet provided at a second end of the inner space, the second magnet being axially spaced from the first magnet. Further, there is an anode cylinder that generates a high frequency provided between the first magnet and the second magnet; a first pole piece and a second pole piece provided proximate first and second openings of the anode cylinder, respectively. Additionally, a seal that prevents outward leakage and has an inward protrusion extending axially toward the anode cylinder; and a choke filter, provided beneath a free end of the inwardly bent end of the seal to prevent outward leakage, may be provided.