Abstract: A rotary x-ray anode with an integrated liquid metal bearing outer shell has an anode disc made of Mo or a Mo-based alloy formed with a hole, which is formed centrally in the region of the axis of rotation and extends in the axial direction at least through part of the anode disc, and a bearing bushing made of Mo or a Mo-based alloy. The bearing bushing is connected to the anode disc via a material bond and its inner wall extends the hole in the anode disc. At least an axial portion of an inner wall of the hole in the anode disc and at least an axial portion of an inner wall of the bearing bushing are formed circumferentially as a liquid metal bearing running surface and they form at least a part of a liquid metal bearing outer shell. There is also described a corresponding production method.

Abstract: A bearing structure for an X-ray tube is provided that includes a journal bearing shaft with a radially protruding thrust bearing encased within a sleeve. The structure of sleeve is formed with enlarged traps or voids in the sleeve that are disposed adjacent various rotating anti-wetting seals/seal surfaces formed between the sleeve and the shaft. The geometry of the traps is formed to retain liquid metal/lubricating fluid within the gap defined by the bearing assembly and to direct to liquid metal flowing outwardly from the gap defined between the sleeve and the shaft away from the rotating anti-wetting seals and back towards the gap. This geometry allows the centrifugal forces exerted on the liquid metal by the rotation of the bearing structure to move the outflowing liquid metal away from the rotating anti-wetting seals to significantly reduce contact of the liquid metal with the seals.

Abstract: Methods and systems for realizing a high speed, rotating anode based x-ray illumination source suitable for high throughput x-ray metrology are presented herein. A high speed rotating anode includes a water cooled rotating platen supported by radial and thrust air bearings employing cascaded differential pumping. A very high bending stiffness of the rotating assembly is achieved by spacing radial air bearings far apart and locating a rotary motor and thrust bearings between the radial air bearings. The high bending stiffness increases the mechanical stability of the rotating assembly during high speed operation, and thus decreases vibration at the location of impingement of the electron beam on the rotating anode material. In some embodiments, magnetic thrust bearings are employed and the air gap is controlled to maintain a desired gap over an operational range of up to three millimeters.

Abstract: A measuring method for a liquid metal slide bearing is disclosed. In at least one embodiment, the measuring method includes providing a liquid metal slide bearing to be measured, the liquid metal slide bearing including two bearing parts with liquid metal being arranged between the two bearing parts. The method further includes measuring inductance, or a variable associated with the inductance, of the liquid metal slide bearing; and determining a quantity of liquid metal in the liquid metal slide bearing based upon the inductance, or the variable associated with the inductance, measured. Furthermore, a corresponding measuring device, a liquid metal slide bearing and an x-ray tube and an apparatus are disclosed.

Abstract: Methods and systems for realizing a high brightness, liquid based x-ray source suitable for high throughput x-ray metrology are presented herein. A high brightness x-ray source is produced by bombarding a rotating liquid metal anode material with a stream of electrons to generate x-ray radiation. A rotating anode support structure supports the liquid metal anode material in a fixed position with respect to the support structure while rotating at the constant angular velocity. In another aspect, a translational actuator is coupled to the rotating assembly to translate the liquid metal anode in a direction parallel to the axis of rotation. In another aspect, an output window is coupled to the rotating anode support structure. Emitted x-rays are transmitted through the output window toward the specimen under measurement. In another further aspect, a containment window maintains the shape of the liquid metal anode material independent of rotational angular velocity.

Abstract: In one embodiment, a rotating anode type X-ray tube comprises a fixed shaft having a first surface, a rotor, a cathode emitting electrons, and an anode target. The rotor comprises a first cylinder having a second surface, a second cylinder, and a third cylinder. A first threaded portion on an inner surface of the first cylinder and a second threaded portion on an outer peripheral surface of the third cylinder are tightened. A screw member is screwed in a third threaded portion on an inner peripheral surface of a hole which penetrates the third cylinder, and a tip portion of the screw member presses the second cylinder against the second surface.

Abstract: There is provided an X-ray tube device having a configuration for preventing peeled-off solid lubrication films from scattering in an X-ray tube even when the solid lubrication film peels off a rotary bearing. The X-ray tube device includes: an anode (212) that is irradiated with an electron beam, thereby emitting X-rays; a rotary bearing (304) that rotatably supports the anode (212); a solid lubrication film which is formed on a front surface of the rotary bearing (304) and into which a ferromagnet is mixed from the rotary bearing (304); and an attractor (303) which attracts, with a magnetic force, the solid lubrication film that peels off the rotary bearing (304).

Abstract: A liquid metal or spiral groove bearing structure for an x-ray tube and associated process for manufacturing the bearing structure is provided that includes a bearing shaft rotatably disposed in a bearing housing or shell. The shell includes a thrust seal engaged with a sleeve to maintain co-axiality for the rotating liquid metal seal formed in the shell about the shaft. The shaft has a bore for the introduction of a cooling fluid into the bearing assembly in which is disposed a cooling tube. The cooling tube includes turbulence-inducing features to increase the turbulence of the cooling fluid flowing through the cooling tube, consequently enhancing the heat exchange between the cooling fluid and the shaft. This maximizes the heat transfer from the shaft to the oil, allowing materials with lower thermal conductivities, such as non-refractory materials, to be used to form the bearing shaft and shell.

Abstract: A liquid metal bearing includes at least one first bearing part and at least one second bearing part that have a non-positive fit connection to one another. At least one first ductile sealing layer is disposed at least partly between at least a first bearing part of the at least one bearing and a second bearing part of the at least one second bearing part.

Abstract: A liquid metal bearing includes at least one first bearing part and at least one second bearing part that have a non-positive fit connection to one another. At least one first ductile sealing layer is disposed at least partly between at least a first bearing part of the at least one bearing and a second bearing part of the at least one second bearing part.

Abstract: The present disclosure is directed towards the prevention of high voltage instabilities within X-ray tubes. For example, in one embodiment, an X-ray tube is provided. The X-ray tube generally includes a stationary member, and a rotary member configured to rotate with respect to the stationary member during operation of the X-ray tube. The X-ray tube also includes a liquid metal bearing material disposed in a space between the shaft and the sleeve, a seal disposed adjacent to the space to seal the liquid metal bearing material in the space, and an enhanced surface area material disposed on a side of the seal axially opposite the space and configured to trap within the enhanced surface area material liquid metal bearing material that escapes the seal.

Abstract: A bearing assembly is disclosed that includes a sleeve having an opening formed therein and a shaft positioned within the opening of the sleeve such that a gap is formed between an inner surface of the sleeve and an outer surface of the shaft. A lubricant is disposed in the gap and a plurality of grooves are formed on at least one of the outer surface of the shaft and the inner surface of the sleeve. An anti-wetting coating is disposed on the at least one of the outer surface of the shaft and the inner surface of the sleeve between adjacent grooves of the plurality of grooves.

Abstract: An x-ray tube includes a frame enclosing a high vacuum, a cathode positioned within the enclosure, a bearing assembly a stationary component comprised of a first base substrate, the first base substrate having a first surface, a rotatable component comprised of a second base substrate, the second base substrate having a second surface, wherein the rotatable component is positioned proximate the stationary component such that a gap is formed between the first surface and the second surface, a liquid metal positioned within the gap, and an antiwetting coating attached to at least one of the first surface and the second surface, the coating includes titanium nitride attached to the at least one of the first surface and the second surface, and an oxide of titanium attached to the titanium nitride.

Abstract: The present disclosure is directed towards the prevention of high voltage instabilities within X-ray tubes. For example, in one embodiment, an X-ray tube is provided. The X-ray tube generally includes a stationary member, and a rotary member configured to rotate with respect to the stationary member during operation of the X-ray tube. The X-ray tube also includes a liquid metal bearing material disposed in a space between the shaft and the sleeve, a seal disposed adjacent to the space to seal the liquid metal bearing material in the space, and an enhanced surface area material disposed on a side of the seal axially opposite the space and configured to trap within the enhanced surface area material liquid metal bearing material that escapes the seal.

Abstract: According to one embodiment, a rotating anode X-ray tube includes a fixed shaft, a rotor, a lubricant, target, and a supporting member. The fixed shaft includes a small-diameter portion provided with a first radial bearing surface including first grooved surfaces, and a large-diameter portion provided with a second radial bearing surface including second grooved surfaces. The rotor includes a third radial bearing surface. The lubricant is filled in a gap between the fixed shaft and the rotor, and drawn by the first and second grooved surfaces.

Abstract: An x-ray tube includes a frame enclosing a high vacuum, a cathode positioned within the enclosure, a bearing assembly a stationary component comprised of a first base substrate, the first base substrate having a first surface, a rotatable component comprised of a second base substrate, the second base substrate having a second surface, wherein the rotatable component is positioned proximate the stationary component such that a gap is formed between the first surface and the second surface, a liquid metal positioned within the gap, and an antiwetting coating attached to at least one of the first surface and the second surface, the coating includes titanium nitride attached to the at least one of the first surface and the second surface, and an oxide of titanium attached to the titanium nitride.

Abstract: An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target, and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap, wherein at least one of the first and second materials comprises tantalum.

Abstract: An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target, and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap, wherein at least one of the first and second materials comprises tantalum.

Abstract: A mechanism to which a liquid-repellent structure hard to be exfoliated is applied. The tip of each of microprojections has a generally spherical surface. When a liquid metal (8) comes into contact with such a surface, the liquid metal (8) cannot enter the spaces among microprojections and is supported by the surfaces of the tips only with point contact. Therefore, the liquid metal (8) neither wets the surface of the base material nor spread over the surface. The liquid-repellent surface (11) has a structure such that the liquid metal (8) is supported by point contact of the many microprojections and repelled by the surface (11), and does not wet the surface (11).

Abstract: An x-ray tube includes a center shaft having an inner surface and an outer surface, the inner surface forming a portion of a cavity therein, a mount having an inner surface, the mount having an x-ray target attached thereto, and a liquid metal positioned between the outer surface of the center shaft and the inner surface of the mount. The x-ray tube further includes a flow diverter positioned in the cavity, the flow diverter having a wall with an inner surface, and a plurality of jets passing through the wall, wherein the plurality of jets are configured such that when a fluid is flowed into the flow diverter and passes along its inner surface, a portion of the fluid passes through the plurality of jets and is directed toward the inner surface of the center shaft.

Abstract: An x-ray tube includes a vacuum enclosure, a shaft having a first end and a second end, a flange attached to the first end of the shaft, the flange having an outer perimeter, and a ferrofluid seal assembly having an inner bore, the inner bore having an outer perimeter smaller than the outer perimeter of the flange. The shaft is inserted through the bore of the ferrofluid seal assembly such that the ferrofluid seal assembly is positioned between the first end of the shaft and the second end of the shaft and such that the first end extends into the vacuum enclosure, and the ferrofluid seal is configured to fluidically seal the vacuum enclosure from an environment into which the second end of the shaft extends.

Abstract: The present invention is related to high power X-ray sources, in particular to those ones that are equipped with rotating X-ray anodes capable of delivering a much higher short time peak power than conventional rotating X-ray anodes according to the prior art. The herewith proposed design principle thereby aims at overcoming thermal limitation of peak power by allowing extremely fast rotation of the anode and by introducing a lightweight material with high thermal conductivity (2) in the region adjacent to the focal track material (4). The extremely fast rotation is enabled by providing sections of the rotary anode disk made of anisotropic high specific strength materials with high thermal stability (1, 3, 6) which will be specifically adapted to the high stresses building up when the anode is operated, as for example fiber-reinforced ceramic materials.

Abstract: An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap. At least one of the first and second materials has a thickness greater than 0.1 mm.

Abstract: An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target, and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap, wherein at least one of the first and second materials comprises tantalum.

Abstract: An x-ray tube includes a cathode and a target assembly positioned to receive electrons emitted from the cathode. The target assembly includes a target and a spiral groove bearing (SGB) configured to support the target. The SGB includes a rotatable component having a first surface and a first material attached to the first surface, a stationary component having a second surface and a second material attached to the second surface, the stationary component positioned such that a gap is formed between the first material and the second material, and a liquid metal positioned in the gap. At least one of the first and second materials has a thickness greater than 0.1 mm.

Abstract: In an X-ray tube, a rotary anode formed into a hollow disk-like shape is fixedly supported by a rotating body formed into a hollow cylindrical shape. A fixed shaft has fixed ends, columnar bearing portions and a disk part, and a flow path of a cooling medium formed along a central axis thereof. The bearing portions are inserted into the rotating body with a first gap between the columnar bearing portion and the rotating body, so that the rotating body is rotatably supported. The disk part is arranged in the rotary anode with a second gap between the disk part and the rotary anode. The first and second gaps are filled with a lubricant, bearing grooves are formed in the bearing portion, thereby forming dynamic pressure bearings, and a center of gravity of the rotary anode is arranged between the first and second dynamic pressure bearings.

Abstract: A mechanism to which a liquid-repellent structure hard to be exfoliated is applied. The tip of each of microprojections has a generally spherical surface. When a liquid metal (8) comes into contact with such a surface, the liquid metal (8) cannot enter the spaces among microprojections and is supported by the surfaces of the tips only with point contact. Therefore, the liquid metal (8) neither wets the surface of the base material nor spread over the surface. The liquid-repellent surface (11) has a structure such that the liquid metal (8) is supported by point contact of the many microprojections and repelled by the surface (11), and does not wet the surface (11).

Abstract: In a rotary anode X-ray tube, a disc portion is fitted into a rotary anode with a first gap therebetween and a fixed shaft is fitted into a rotary shaft to support the anode with a second gap therebetween. The disc portion and the fixed shaft are formed integral with each other to have a hollow portion therein. A cooling liquid is allowed to flow through the hollow portion. A liquid metal is filled in the first and second gaps. Dynamic pressure type bearings is formed in the second gap. A passage is formed to directly communicate the first gap to the second gap, whereby the liquid metal being directly supplied from the second gap to the first gap. Thus, the liquid metal can be fed rapidly and surely into the gap between the anode target and a cooling vessel.

Abstract: An x-ray tube having a liquid lubricated bearing assembly and a liquid cooled anode target. The anode target and bearing assembly having increased lubrication and cooling to withstand higher power, higher temperature and higher load applications.

Abstract: A rotating anode X-ray tube includes a fixed body having a radial sliding bearing surface and a channel therein through which a coolant flows, a rotor including a discoid large-diameter portion, which has a recess fitted with one end portion of the fixed body with a clearance therebetween and constitutes an anode target, and a small-diameter portion, which has on an inner surface thereof a radial sliding bearing surface which faces the aforesaid radial sliding bearing surface with a clearance, and is united with the large-diameter portion at one end portion thereof, a lubricant filling the clearances, a cathode arranged opposite to the anode target, and a vacuum envelope which contains the fixed body, the rotor, the lubricant and the cathode, and fixes the fixed body at another end portion of the fixed body situated opposite the one end portion of the fixed body fitted in the recess.

Abstract: In an X-ray tube, a rotary anode formed into a hollow disk-like shape is fixedly supported by a rotating body formed into a hollow cylindrical shape. A fixed shaft has fixed ends, columnar bearing portions and a disk part, and a flow path of a cooling medium formed along a central axis thereof. The bearing portions are inserted into the rotating body with a first gap between the columnar bearing portion and the rotating body, so that the rotating body is rotatably supported. The disk part is arranged in the rotary anode with a second gap between the disk part and the rotary anode. The first and second gaps are filled with a lubricant, bearing grooves are formed in the bearing portion, thereby forming dynamic pressure bearings, and a center of gravity of the rotary anode is arranged between the first and second dynamic pressure bearings.

Abstract: A rotating anode X-ray tube includes a fixed body having a radial sliding bearing surface and a channel therein through which a coolant flows, a rotor including a discoid large-diameter portion, which has a recess fitted with one end portion of the fixed body with a clearance therebetween and constitutes an anode target, and a small-diameter portion, which has on an inner surface thereof a radial sliding bearing surface which faces the aforesaid radial sliding bearing surface with a clearance, and is united with the large-diameter portion at one end portion thereof, a lubricant filling the clearances, a cathode arranged opposite to the anode target, and a vacuum envelope which contains the fixed body, the rotor, the lubricant and the cathode, and fixes the fixed body at another end portion of the fixed body situated opposite the one end portion of the fixed body fitted in the recess.

Abstract: In a rotary anode X-ray tube, a disc portion is fitted into a rotary anode with a first gap therebetween and a fixed shaft is fitted into a rotary shaft to support the anode with a second gap therebetween. The disc portion and the fixed shaft are formed integral with each other to have a hollow portion therein. A cooling liquid is allowed to flow through the hollow portion. A liquid metal is filled in the first and second gaps. Dynamic pressure type bearings is formed in the second gap. A passage is formed to directly communicate the first gap to the second gap, whereby the liquid metal being directly supplied from the second gap to the first gap. Thus, the liquid metal can be fed rapidly and surely into the gap between the anode target and a cooling vessel.

Abstract: A bearing assembly mounted in an x-ray tube includes a bearing race and a bearing ball positioned adjacent to the bearing race. A lubricant is deposited on a first portion of a bare metal of one of the bearing race and the bearing ball, and a metal matrix deposited on a second portion of the bare metal.

Abstract: A bearing assembly for an x-ray tube is disclosed that includes a bearing race, a bearing ball positioned adjacent to the bearing race, and a combination coating deposited on one of the bearing race and the bearing ball. The combination coating includes titanium carbide and a solid lubricant.

Abstract: A method for manufacturing an x-ray tube bearing cage includes the step of forming a bearing cage from a carbon-carbon composite material. A coating is applied to the carbon-carbon composite bearing cage. The coating includes an outer layer formed of a dry film lubricant. The coated carbon-carbon composite bearing cage is included in a bearing assembly in the x-ray tube and forms a lubricious enclosure for bearing balls positioned therein to minimize wear and heat generation in the bearing assembly.

Abstract: A method for manufacturing an x-ray tube bearing cage includes the step of forming a bearing cage from a carbon-carbon composite material. A coating is applied to the carbon-carbon composite bearing cage. The coating includes an outer layer formed of a dry film lubricant. The coated carbon-carbon composite bearing cage is included in a bearing assembly in the x-ray tube and forms a lubricious enclosure for bearing balls positioned therein to minimize wear and heat generation in the bearing assembly.

Abstract: A bearing assembly mounted in an x-ray tube includes a bearing race and a bearing ball positioned adjacent to the bearing race. A coating is deposited on one of the bearing race and the bearing ball includes a lubricant and a hard material having a hardness greater than a base material of the bearing race and a base material of the bearing ball.

Abstract: A valve is provided to fill a chamber for holding a rotation shaft of a rotating anode in an X-ray tube. The valve has a needle supported on a seat. The needle maintains the vacuum in the tube. A sleeve can engage in the valve. The sleeve is hollow and has a cavity. This cavity can be connected to the vacuum or to a bottle under vacuum filled with a lubricant liquid. The sleeve is used to handle the needle. The sleeve furthermore bears on a rim of the valve by an O-ring joint. This joint maintains the vacuum when the needle is raised and when the tube under vacuum is connected to the cavity of the sleeve.

Abstract: A system for controlling a gas load imposed upon a high vacuum chamber includes a first chamber enclosing a high vacuum and positioned within an ambient environment, a second chamber enclosing a gas and positioned within the ambient environment adjacent to the first chamber, and a rotatable shaft having a first portion extending into the first chamber and a second portion extending into the second chamber. A ferrofluid seal is positioned about the rotatable shaft and positioned between the first portion and the second portion and the ferrofluid seal fluidically separates the first chamber from the second chamber. A control unit is attached to the second chamber and configured to control the gas enclosed in the second chamber such that a gas load in the first chamber is reduced.

Abstract: A bearing assembly mounted in an x-ray tube includes a bearing race and a bearing ball positioned adjacent to the bearing race. A lubricant is deposited on a first portion of a bare metal of one of the bearing race and the bearing ball, and a metal matrix deposited on a second portion of the bare metal.

Abstract: A bearing assembly mounted in an x-ray tube includes a bearing race and a bearing ball positioned adjacent to the bearing race. A coating is deposited on one of the bearing race and the bearing ball includes a lubricant and a hard material having a hardness greater than a base material of the bearing race and a base material of the bearing ball.

Abstract: A system and method for providing a sealing arrangement in an X-ray tube are provided. The X-ray tube includes a rotating portion having a plurality of ball bearings and a liquid metal within a housing having the ball bearings therein. The rotating portion is configured to rotate an anode. The X-ray tube further includes a sealing portion formed by a liquid metal vacuum interface configured in a radial direction to resist flow of liquid metal from the housing to a vacuum portion.

Abstract: A cooled radiation emission device has an enclosure in which X-rays are produced. In the enclosure, there is a cathode, an anode situated facing the cathode and rotating on a shaft, and a fixed anode shaft support. The support includes a holding chamber, the shaft of the anode being held in the chamber. The cooling of the tube uses a gallium-indium-tin liquid alloy flow through the anode shaft. This alloy is a conductor of heat and electricity. At the same time as the lubrication of the bearings and the electrical powering of the anode, it provides for cooling of the anode.

Abstract: An anode target is roratably supported by a rotating mechanism having a rotary body and a staionary body. A fitted portion between the rotary body and the stationary body is formed of bearing areas having dynamic pressure type sliding bearings and a non-bearing area having a clearance between the rotary body and the stationary body larger than that in the bearing areas. The rotary body facing the non-bearing area is positioned where a time for heat transfer from the anode target is shorter than the rotary body facing the bearing areas. Thus, the characteristics of heat radiation from the anode target can be improved, and a stable bearing operation can be maintained.

Abstract: A rotating anode bearing housing includes an x-ray tube frame (106) that has a vacuum chamber (108). An anode (110) resides within the vacuum chamber (108) and rotates on a shaft (114) via a bearing (117). The bearing (117) is attached to an interior surface (126) of the x-ray tube frame (106). The bearing (117) transfers thermal energy from the shaft (114) to the x-ray tube frame (106).

Abstract: Liquid metal gaskets for use in vacuum tubes are provided. Such liquid metal gaskets are ideal for use in x-ray tubes in x-ray imaging systems. These liquid metal gaskets comprise an internal plug incorporating a liquid metal filling, a first seal connected to a first end of the internal plug so as to isolate a bearing assembly from a vacuum vessel portion of the vacuum tube, and a second seal connected to a second end of the internal plug so as to prevent particles and vapors in a cavity of the bearing assembly from migrating into a vacuum area of the x-ray tube. The liquid metal gaskets incorporate any suitable liquid metal, such as mercury, gallium, or a gallium alloy. The liquid metal gaskets allow any suitable type of bearing assembly lubricant to be used, such as oils, powders, liquids, solids, wetting metals, and the like.

Abstract: An anode target (22) is rotatably supported by a rotating mechanism (25) having a rotary body (23) and a stationary body (28). A fitted portion between the rotary body (23) and the stationary body (28) is formed of bearing areas (L1) to (L4) having dynamic pressure type sliding bearings and a non-bearing area (L5) having a clearance between the rotary body (23) and the stationary body (28) larger than that in the bearing areas (L1) to (L4). The rotary body facing the non-bearing area is positioned where a time for heat transfer from the anode target (22) is shorter than the rotary body facing the bearing areas. Thus, the characteristics of heat radiation from the anode target (22) can be improved, and a stable bearing operation can be maintained.

Abstract: Disclosed is a rotary anode type X-ray tube comprising an anode target emitting an X-ray, a rotating mechanism for rotatably supporting the anode target, the rotating mechanism including an inside rotor and a stator, bearings being arranged between the inside rotor and the stator, and a vacuum envelope housing the anode target and the rotating mechanism. Dynamic slide bearings each using a liquid metal lubricant and ball bearings are used as the bearings arranged between the inside rotor and the stator.

Abstract: A bearing assembly for a rotating anode x-ray device. The bearing assembly includes a shaft having a flange at one end for attachment of the anode thereto. The shaft defines front and rear inner races and includes a plurality of extended surfaces. Front and rear outer race elements define front and rear outer races, respectively, corresponding to the front and rear inner races, respectively, defined by the shaft. The front and rear outer race elements cooperate with the shaft to confine front and rear ball sets which facilitate rotary motion of the shaft. A spacer including extended surfaces assists in the positioning of the front and rear outer race elements in a bearing housing. The extended surfaces of the shaft and spacer, in conjunction with emissive coatings provided on various portions of selected components of the bearing assembly, facilitate a relative improvement in heat transfer out of the bearing assembly.