67results about "Discharge tube solid thermionic cathodes" patented technology

The invention relates to an electron extraction method and system for a low-energy electron source. The method comprises the following steps: providing at least one cathode, at least one heating power supply and at least one control electrode; in a first time period, the heating power supply provides heating current for the cathode, so that the temperature of the cathode is increased to be higher than an electron emission threshold value, meanwhile, the potential difference between the control electrode and the cathode is controlled to be a suppression value, and electrons generated by the cathode are prevented from reaching a preset target spot; and in the second time period, the current is stopped from being supplied to the cathode, and meanwhile, the potential difference between the control electrode and the cathode is controlled to reach a guide value, so that electrons emitted by the cathode through waste heat reach the preset target spot and interact with target particles. Cathode heating is controlled in an intermittent energization mode, and accurate extraction of the low-energy scattered electron beam is achieved.

[Problem] To provide novel technology. [Solution] One aspect of the present invention provides a thermionic cathode. The thermionic cathode includes an electron source and a plurality of grids. The electron source is configured to emit electrons when heated. The plurality of grids have through-holes that allow electrons emitted from the electron source to pass in a predetermined direction. At least one of the grids is configured to reduce the movement speed of the electrons.

The electron source is provided with: an electron emission unit containing an alloy of iridium and a rare earth element; a support part made of metal; and a joining part that joins the electron emission part and the support part. The bonding portion has a coating layer containing iridium and the metal in the support portion, and the coating layer contains iridium and the metal in the support portion.

A cathode device with an electrical contact junction that operates cooler and has more stable electrical resistance than prior art Provision of. The cathode device includes an emitter tip (16) for generating electrons. It includes an elongated heater (14) having a proximal end and a distal end. The emitter tip can be located at the distal end of the heater. Two spaced-apart legs (15a, 15b) extend away from the heater's distal end and terminate at the proximal end, forming an elongated slot therebetween. Two electrical contacts (20) compressively engage opposite outer surfaces of the two legs at the heater's proximal end to mechanically secure and electrically connect the two legs to their respective electrical contacts at a junction located away from the emitter tip to maintain a lower junction temperature.

According to the cathode structure of the ionizer, a large arc structure formed by winding one metal hot wire in the prior art is changed into a small arc structure formed by winding two metal hot wires, the pins are arranged at the two ends of each metal hot wire, and the metal hot wires are fixed to the sheet electrodes through the pins, so that the cathode structure of the ionizer is formed. According to the metal hot wire, the first end of the sheet-shaped electrode is provided with a pin positioning groove or an arc-shaped surface and a limiting step, so that the original multi-point welding between the linear pin and the sheet-shaped electrode is changed into straight welding, the angular tensile stress during welding is reduced, the metal hot wire is not prone to deformation in the assembling process, and the concentricity of the metal hot wire and other electrodes is kept; the stability of a small arc structure formed after welding is improved, a welding area of the metal hot wire and the sheet electrode is far away from a high-temperature area of the metal hot wire by arranging the linear pins, an effective electron emission area is enlarged, and heat loss generated by heat conduction is reduced. The efficiency of the metal heating wire is remarkably improved, the metal heating wire is not prone to fusing failure, and the service life is prolonged.

A method for manufacturing an electron source according to the present disclosure includes steps of: (A) preparing a first member provided with a columnar portion made of a first material having an electron emission characteristic, (B) preparing a second member which has a higher work function and a lower strength than the first material, and in which a hole is formed extending in a direction from one end surface toward the other end surface, and (C) pushing the columnar portion into the hole in the second member, wherein the first member has a cross-sectional shape that is dissimilar to the cross-sectional shape of the hole; and in the step (C), by pressing the columnar portion into the hole, a portion of a side surface of the columnar portion scrapes the inner surface of the hole and bites into the second member, thereby fixing the columnar portion to the second member.

An ion source for forming a plasma includes a cathode having a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially surrounding the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, and the cathode gap defines a tortuous path for restricting movement of the plasma through the gap. The cathode surface may have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter. The first cathode diameter and the second cathode diameter are different from each other to define the cathode step. The stepped cylindrical surface may be an outer surface or an inner surface. The first cathode diameter and the second cathode diameter may be concentric or axially offset.

The invention belongs to the technical field of electron flow emitting devices, and particularly relates to a device for enhancing electron emission guidance quality, which comprises a base, a guide piece column and at least one lamp filament, each pair of conductive columns penetrate through the base and are electrically connected with a power supply, and the lamp filament is electrically connected with the conductive columns. The conductive column is fixedly installed on the base, the lamp filament is installed on the base, the insulating parts are arranged at the two ends of the connecting position of the conductive column and the base respectively and wrap the conductive column, and the guiding part is fixedly installed on the base and located behind the lamp filament so that the situation that electrons emitted by the lamp filament thermally flow to a non-working area to be dissipated can be reduced. The density of the electron flow is controlled, the use of multiple working areas is met, and the dissipation direction of the electron flow can be controlled through the guide piece.

Various methods and systems are provided for an emitter assembly for a cathode of an X-ray tube. In one example, an emitter assembly comprises a first end of a substantially flat emitter supported by two rods extending from a two-rod insulator assembly, and a second end of the substantially flat emitter supported by a compliant, single rod insulator assembly.

To provide an electron source which can have sufficient electron emission characteristics even after a certain time elapses from start of emission of electrons, and to provide a manufacturing method of the electron source.SOLUTION: An electron source 100 includes: an electron emission member 10 containing iridium and lanthanoid; a conductive support member 20 which supports the electron emission member 10; and a conductive member 30 disposed between the electron emission member 10 and the support member 20 and in contact with both. In a manufacturing method of the electron source 100, the electron emission member 10 and the support member 20 are joined through the conductive member 30.SELECTED DRAWING: Figure 2

To provide an indirect heated cathode capable of shortening the time up to a start of radiation of thermoelectrons, and a method of manufacturing the indirect heated cathode in which a heat absorption layer which has a uniform thickness can be easily manufactured.SOLUTION: An indirect heated cathode 10 comprises a cathode sleeve 1, a heater 2 arranged at a hollow part of the cathode sleeve 1, a black heat absorption layer 4 covering a hollow part inner surface of the cathode sleeve 1, and a cathode base body 3 carrying an electron emission substance arranged at the cathode sleeve 1. The black heat absorption layer 4 consists of a particulate substance including tungsten and aluminum oxide. The black heat absorption layer 4 is formed by arranging rod-like alumina ceramics, and a first tungsten heater and a second tungsten heater in the hollow part of the cathode sleeve 1 and heating it in a vacuum atmosphere.SELECTED DRAWING: Figure 1

An emitter (1) having: an electron source tip (10); a first filament (50) connected to a first position (10a) on the side surface of the electron source tip (10); a second filament (60) connected to a second position (10b) on the side surface of the electron source tip (10); two upper positive terminals (20a, b) connected to first side surfaces (50a, b) at two locations of the first filament (50), respectively; two upper negative terminals (20c, d) connected to second side surfaces (60a, b) at two locations of the second filament (60), respectively; one lower positive terminal (30a) electrically connected to the two upper positive terminals (20a, b); one lower negative terminal (30b) electrically connected to the two upper negative terminals (20c, d); and an insulator (40) carrying the upper positive terminals (20a, b), the upper negative terminals (20c, d), the lower positive terminal (30a), and the lower negative terminal (30b), the first position (10a) and the second position (10b) being different positions, the first side surfaces (50a, b) of the first filament (50) being connected to the side surfaces of the upper positive terminals (20a, b), respectively, and the second side surfaces (50a, b) being connected to the side surfaces of the lower positive terminals (30a, b). The second side surfaces (60a, b) of the second filament (60) are connected to the side surfaces of the upper negative terminals (20c, d), respectively.

In one embodiment, a system includes a cathode and a thermionic emitter installed at least partially within the cathode tube of the cathode. The thermionic emitter is in a shape of a hollow cylinder. The hollow cylinder includes an outer surface and an unsmooth inner surface. The outer surface is configured to contact an inner surface of the cathode tube. The unsmooth inner surface includes a plurality of structures that provide an increase in surface area over a smooth surface.

An electron beam generating source includes an electron emitting portion extending in a desired axis and emitting electrons, a movable portion connected to one end of the electron emitting portion, a support portion supporting the movable portion in a manner that the movable portion is movable along the axis, and a tension maintaining portion maintaining tension of the electron emitting portion by applying a pressing force or a stretching force to the movable portion. The movable portion and the tension maintaining portion are disposed on the axis, respectively.

The invention provides a heater-free hollow cathode with a built-in tungsten filament electrode, and belongs to the technical field of spaceflight related equipment manufacturing. An emitter is arranged on the upper portion of the inner side wall of a cathode tube and tightly attached to the inner side wall of the cathode tube, the outlet end of the top of the cathode tube is connected with a throttling top in a sealed mode, a first flow channel of the throttling top is communicated with the cathode tube and an emitter cavity, the cathode tube is coaxially sleeved with a touch holding electrode, and the bottom end of the cathode tube is fixedly connected with the top end face of a ceramic base. The built-in tungsten filament electrode is fixed in the second flow channel of the ceramic base, the top end of the built-in tungsten filament electrode is arranged in the cavity of the emitter and does not make contact with the surface of the emitter, the first through hole of the ceramic base is communicated with the third flow channel and sealed, and a ceramic insulating layer is arranged on the bottom end face of the touch holding electrode. And the two conductive columns pass through the two through holes II of the ceramic insulating layer and are fixedly connected with the contact holding electrode. In the cathode starting process, an external heating structure of a traditional cathode can be optimized by means of the heat emission effect of a tungsten filament in the cathode, and therefore miniaturization of the cathode is achieved.

A filament assembly 10 for an x-ray tube 20 can include a planar filament 11 electrically-coupled between and substantially-encircled by a pair of collector plates C1 and C2. The pair of collector plates C1 and C2 can support the planar filament 11 so that it does not twist or warp and align the filament assembly 10 within a cathode cup 33. The pair of collector plates C1 and C2 can block electrons emitted from a back side of the filament. Without the collector plates C1 and C2, back side electrons can change direction by about 180°, hit the target, and distort a target electron spot. Each collector plate C1 or C2 can include holes H1 and H2. These holes H1 and H2 can aid in alignment of the collector plates C1 and C2 with electrodes 31 and electrode 32, can allow welding at a lower temperature, and can facilitate weld inspection.

A monolithic graphite heater for heating a thermionic electron cathode includes first and second electrically conductive arms, each one of the first and second electrically conductive arms having an electrode mount at a proximal end, a thermal apex at a distal end, and a transitional region between the electrode mount and the thermal apex; a cathode mount electrically and mechanically coupling each thermal apex to form a maximum Joule-heating region at or adjacent the cathode mount and decreasing Joule heating along each transitional region; and a press-fit aperture formed in the cathode mount, the press-fit aperture sized to receive at least a portion of the thermionic electron cathode for facilitating thermionic emission produced therefrom in response to operative heat power generation provided by the maximum Joule-heating region.

The application discloses a barium tungsten lanthanum hexaboride composite hollow cathode, which comprises a cathode tube, a gas inlet is arranged at a first end of the cathode tube, a cathode top is arranged at a second end of the cathode tube, and a cathode top through hole is arranged in the cathode top; a touch electrode is arranged outside the cathode tube, an end of the touch electrode is provided with a touch electrode top, a touch electrode through hole is arranged in the touch electrode top, and the touch electrode is coaxial with the cathode tube; an emitter comprises a first emitter and a second emitter, the first emitter and the second emitter are sequentially arranged on an inner wall of the second end of the cathode tube in a direction from the gas inlet to the cathode top; a heater is arranged around an outer wall of the cathode tube; wherein the first emitter is a barium tungsten emitter, the second emitter is a lanthanum hexaboride emitter, and the lanthanum hexaboride emitter is heated by heat generated by self-sustaining work of the barium tungsten emitter, so that the starting power consumption is greatly reduced.

The invention relates to the field of electronic gun power supplies, and discloses an electronic gun filament power supply isolation device and electronic gun equipment, and the electronic gun filament power supply isolation device comprises a driving circuit which is used for outputting a driving signal when receiving a control signal; the first motor is connected with the driving circuit, and the first motor is used for working when receiving the driving signal; the insulation transmission structure is connected with the first motor; the second motor is connected with the insulation transmission structure and is also used for connecting an electron gun filament; the first motor drives the insulation transmission structure to rotate when working so as to drive the second motor to generate alternating current and output the alternating current to the electron gun filament. Through the first motor, the insulation transmission structure and the second motor, conversion from electric energy to mechanical energy and then to the electric energy is achieved, the structural design of a power circuit is simplified while electrical isolation and insulation are achieved, and the energy transmission efficiency is improved.

An ion source is disclosed which may be used to introduce a dopant material into an arc chamber. A component containing the dopant material is placed in the path of the etching gas entering the arc chamber. In some embodiments, the dopant material is in liquid form, and the etching gas moves through the liquid. In several other embodiments, the dopant material is a solid material. In some embodiments, the solid material is formed as a porous structure, thereby allowing the etching gas to flow through the solid material. In several other embodiments, one or more components of the ion source are manufactured using a material containing the dopant material, thereby allowing the etching gas to etch the component to release the dopant material.

An emitter comprises: an insulator; a pair of terminals extending along a first direction and fixed to the insulator so as to face each other in a second direction perpendicular to the first direction; a filament fixed to the pair of terminals; and a chip part formed of an electron emission material and fixed to the filament. Each of the pair of terminals has an inclined surface that is on one side in a third direction perpendicular to the first direction and the second direction and that is inclined with respect to the first direction so as to slope toward the other side in the third direction as it gets farther from the insulator. The filament is fixed to the pair of terminals at the inclined surface thereof.

To provide a new technology.SOLUTION: A thermionic cathode according to an embodiment of the present invention includes an electron source and a plurality of grids. The electron source is configured to emit electrons when heated. The plurality of grids have through holes that allow electrons emitted from the electron source to pass in a predetermined direction. At least one of the grids is configured to slow down the traveling speed of the electrons.SELECTED DRAWING: Figure 1

The present invention relates to the technical field of filament cathode materials. Disclosed are a tungsten carbide alloy filament and a preparation method therefor, and a heating device. The tungsten carbide alloy filament comprises a base body (100) and a carbonization layer (200) attached to the outer surface of the base body (100), wherein the grain width of the carbonization layer (200) is 1.0-15.0 µm; the components of the base body (100) and the carbonization layer (200) both comprise tungsten, carbon, oxygen and an M element, the M element being selected from one or a combination of more of La, Y, Sc, Nd, Sm, Lu, Ce, Gd, Tb, Dy, Ho, Pr, Er, Tm, Yb, Eu, Hf and Zr; and the components of the tungsten carbide alloy filament do not contain thorium. The material improves the emission stability of the tungsten alloy filament, and can also reach stable emission capability of a traditional thorium-tungsten filament without adding thorium, thereby solving the problem of relatively poor stable emission capability of an existing thorium-free tungsten filament, and avoiding the radioactive contamination problem of a traditional thorium-tungsten filament.

The application discloses a kind of hot emission cathode based on microwave enhancement control, belongs to space electric propulsion field and electric vacuum device field, the present application is to solve the problem of conventional hot emission cathode electron emission current regulation and control ability, the big interference of plasma environment.For solving the problem of conventional hot emission cathode electron emission current regulation and control ability, the big interference of plasma environment.The present application includes hot electron emission unit, microwave feed-in joint and resonant chamber, hot electron emission unit is coaxially arranged in resonant chamber;Microwave feed-in joint is inserted into resonant chamber from side vertical cavity and is connected with the waveguide of hot electron emission unit;Hot electron emission unit is used to emit hot electron under direct current electric field;Microwave feed-in joint is used to feed microwave into resonant chamber, and microwave is repeatedly reflected at open end and short end of resonant chamber, to form standing wave on the waveguide surface of electron emission unit, and to form strong standing wave electric field on the emitter of electron emission unit, to realize the regulation and control of increasing electron emission current.

The present invention discloses a magnetic deflection array cathode, comprising: a housing, a grid structure, and a deflection member; the grid structure and the deflection member are installed inside the housing; the grid structure is used to generate electrons; and the deflection member is used to deflect and accelerate the electrons. The present invention, by using a chip selection electrode, can avoid failure of the entire device due to a short circuit between part of the cathode body and the anode, thereby improving the reliability and life of the cathode. At the same time, the use of a magnetic deflection method to lead out the electron beam can also reduce the cathode body from being bombarded by environmental pollution and external ions, etc., which can cause product failure, thereby increasing product reliability. By adding a grid assembly to the lead-out end, the electron beam can be focused and the energy enhanced, so that the electron source can be used in situations where current is required.

The utility model belongs to the technical field of electron flow emitting devices, and particularly relates to a device for enhancing electron emission guidance quality, which comprises a base, a guide piece column and at least one lamp filament, each pair of conductive columns penetrate through the base and are electrically connected with a power supply, and the lamp filament is electrically connected with the conductive columns. The two ends of the connecting position of the conductive column and the base are respectively provided with an insulating part wrapping the conductive column, and the guiding part is fixedly installed on the base and located behind the lamp filament so as to reduce the phenomenon that electrons emitted by the lamp filament thermally flow to be dissipated in a non-working area. A plurality of independent power supplies can be connected so as to control the density of the electron flow, the use of multiple working areas is met, and the dissipation direction of the electron flow can be controlled through the guide piece.

The invention relates to a flat emitter with compliant support ends. Various methods and systems are provided for an emitter assembly for a cathode (352) of an X-ray tube. In one example, a transmitter assembly includes: a first end (426) of a substantially planar transmitter (424) supported by a dual pole extending from a dual pole insulator assembly (420); and a second end portion (428) of the substantially planar emitter (424), the second end portion being supported by a compliant single pole insulator assembly (414).

Various methods and systems are provided for an emitter assembly for a cathode (352) of an X-ray tube. In one example, an emitter assembly comprises a first end (426) of a substantially flat emitter (424) supported by two rods extending from a two-rod insulator assembly (420), and a second end (428) of the substantially flat emitter (424) supported by a compliant, single rod insulator assembly (414).