With Movable Target Patents (Class 378/125)
  • Patent number: 5020087
    Abstract: Diode for providing X-rays. A diode for generating X-rays is adapted for connection to a source of high electrical energy with the diode having a first end from which the X-rays are emitted, a second end, and axis extending between the ends. The diode includes a ring cathode connected to the electron source and an intermediate anode spaced from the cathode with at least a portion of this anode being disposed between the ring cathode and the diode first end. The intermediate anode decelerates electrons to cause the generation of X-rays emitted from the diode first end. The diode also includes an intermediate cathode disposed radially outwardly of the intermediate anode and connected to this anode. The diode further includes an inverse anode spaced from the intermediate cathode and positioned radially outwardly of the intermediate cathode and between the intermediate cathode and between the intermediate cathode and the diode second end.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: May 28, 1991
    Assignee: Maxwell Laboratories, Inc.
    Inventors: William H. Rix, John P. Shannon, deceased
  • Patent number: 5010562
    Abstract: The generation of excessive electron radiation or X-ray radiation is prevented in an apparatus which comprises an accelerator means for generating and accelerating electrons. These electrons form an electron beam which has a predetermined low intensity level for the generation of electron radiation or a predetermined high intensity level for the generation of X-ray radiation. In case of generating electron radiation a scattering foil or a target, respectively are arranged in the trajectory of the electron beam. The foil and the target are movably arranged on a support means.
    Type: Grant
    Filed: August 31, 1989
    Date of Patent: April 23, 1991
    Assignee: Siemens Medical Laboratories, Inc.
    Inventors: Francisco Hernandez, Jerry Chamberlain
  • Patent number: 5008918
    Abstract: A composite target for an x-ray tube has a graphite substrate portion and a metal portion, the two portions being bonded together by platinum and platinum alloying materials. The preferred alloying materials are tungsten and nickel which act in conjunction with the platinum to improve the bond resulting in an x-ray tube having a longer life span.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: April 16, 1991
    Assignee: General Electric Company
    Inventors: David S. Lee, Thomas C. Tiearney, Jr.
  • Patent number: 4993055
    Abstract: X-ray tube includes a rotatable envelope in which is mounted an electron gun at one end and a target anode at the other end. A fixed means for deflecting the electron beam from the electron gun is provided to deflect the electron beam on a fixed path as the envelope of the x-ray tube rotates about an axis. The electron beam being confined to a fixed path results in the electron beam striking various positions of the target anode to provide for improved heat dissipation. The electron beam is deflected along the fixed path using magnetic deflection means including magnetic deflection coils positioned external of the envelope to provide a deflection field transverse to the electron beam. The target anode is cooled by directing a cooling fluid on an external side of the target anode.
    Type: Grant
    Filed: November 23, 1988
    Date of Patent: February 12, 1991
    Assignee: Imatron, Inc.
    Inventors: Roy E. Rand, Douglas P. Boyd, Kristian R. Peschmann
  • Patent number: 4993054
    Abstract: An improved rotary x-ray target wherein a rotor stud member is fastened to a hub portion, with both the stud member and the hub portion composed of a refractory metal. The fastening of the stud member to the hub portion is effected by a brazing alloy composed of the following ranges of metals expressed in weight percent: 30-70 copper; 10-55 palladium and 5-28 nickel. The brazed joint has a liquidus temperature in the range of 1145.degree.-1200.degree. C. and thus allows operating temperatures for the stud/hub joint of at least as high as 1000.degree. C.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: February 12, 1991
    Assignee: General Electric Company
    Inventor: Paul U. Ujari
  • Patent number: 4991194
    Abstract: The invention relates to a rotating anode for an X-ray tube, which avoids the anarchical generation of cracks in a target carried by the anode. For this purpose, at least a part of a target area is carved by a plurality of radial slots arranged symmetrically with respect to an axis of symmetry of the anode. The depth of the slots is less than the thickness of the target.
    Type: Grant
    Filed: December 29, 1988
    Date of Patent: February 5, 1991
    Assignee: General Electric CGR S.A.
    Inventors: Michel Laurent, Pierre Noualhaguet, Claude Mathieu
  • Patent number: 4969172
    Abstract: An x-ray tube rotor structure wherein a target support stem has an externally threaded end portion engaged with an internally threaded surface of an encircling bushing and fixedly attached thereto by an interposed brazed joint. The stem is made of predominantly molybdenum material having a linear thermal expansion coefficient of 58.times.10.sup.-7 per degree Fahrenheit and is thermally matched with the bushing which is made of an iron cobalt nickel alloy material having a linear thermal expansion coefficient of 60.times.10.sup.-7 per degree Fahrenheit. The bushing has an outer surface fixedly attached through a welded joint with an inner surface of an annular plug which has an outer marginal portion fixedly attached to an adjacent end portion of a coaxial rotor skirt. The annular plug is made of an iron chrome nickel alloy material having a linear thermal expansion coefficient of 84.times.10.sup.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: November 6, 1990
    Assignee: Machlett Labs. Inc.
    Inventors: Albert F. Fengler, Raymond A. Daly, Ming-Wei P. Xu, Steven Tavoletti, Thomas J. Koller
  • Patent number: 4964147
    Abstract: The invention relates to an X-ray tube with a rotating anode which is driven by a magnetic bearings motor. The anodic current is outflowed by a friction-type contact device which is located inside the shaft supporting the rotor of the motor. The friction contact device is actuated so as to cut off or establish an electrical contact between an inner wall of the rotor and the friction contact device.
    Type: Grant
    Filed: January 17, 1989
    Date of Patent: October 16, 1990
    Assignee: General Electric CGR SA
    Inventors: Michel Laurent, Pierre Noualhagnet, Claude Mathieu
  • Patent number: 4962519
    Abstract: A bearing retainer for mounting for a bearing in an X-ray tube, the X-ray tube having a rotating anode supported on an anode shaft held within a hollow anode stem, the retainer being slidably fitted into a hollow anode stem to hold one bearing coaxially with the anode shaft and to permit axial motion of the bearing so held, where the sliding surface of the bearing retainer is coated with a solid lubricant, and wherein the bearing retainer includes a bearing flange not coated with lubricant which may be swaged around the outer race of the bearing to hold the bearing.
    Type: Grant
    Filed: January 22, 1990
    Date of Patent: October 9, 1990
    Assignee: General Electric Company
    Inventor: Kamleshwar Upadhya
  • Patent number: 4939762
    Abstract: An X-ray target having a graphite body and an X-ray generating metal coating layer, in that a metal interlayer which is non-reactive with graphite and which has a coefficient of thermal expansion substantially equal to those of the graphite and the X-ray generating metal coating layer is formed at the boundary between the graphite body and the X-ray generating metal coating layer, and that the interlayer is caused to percolate into the graphite body. Desirably, the interlayer includes a part percolating into the graphite body over a depth of at least 10 .mu.m. The X-ray target can be manufactured in such a way that the surface of the graphite body is coated with the metal interlayer by subjecting the surface to chemical vapor deposition under a normal pressure or under a pressure near the normal pressure, and that the metal interlayer is thereafter coated with an X-ray generating metal by an expedient such as chemical vapor deposition, sputtering or thermal spraying.
    Type: Grant
    Filed: November 15, 1988
    Date of Patent: July 3, 1990
    Assignees: Hitachi, Ltd., Hitachi Medical Corporation
    Inventors: Noboru Baba, Yusaku Nakagawa, Masatake Fukushima, Masateru Suwa, Ichiro Inamura
  • Patent number: 4935948
    Abstract: An arrangement for reducing noise in an X-ray tube uses a ring mass disposed on the bearing shroud. The ring mass dissipates vibrational energy which would otherwise be transmitted to the glass envelope of the vacuum tube within the casing of the X-ray tube. The ring mass, which is tightly coupled to the bearing shroud, is mounted adjacent the neck of the glass envelope of the vacuum tube. The ring mass is made of lead and may have two ends at a split so that a bolt may tighten the ring around the bearing shroud.
    Type: Grant
    Filed: December 12, 1988
    Date of Patent: June 19, 1990
    Assignee: General Electric Company
    Inventor: Jeung T. Kim
  • Patent number: 4920551
    Abstract: A rotating anode X-ray tube is provided which includes an anode disk having a central axis of rotation and a circumferential peripheral edge lying in a plane perpendicular to that axis of rotation. A ring-shaped target is mounted to the disk adjacent the peripheral edge and the disk includes a mechanism formed integrally solid with the disk and remote from the target for mounting the disk to a support shaft of a rotor within a vacuum housing to permit rotation of the disk about the axis of rotation of the disk. The disk is formed integrally solid along the aforementioned plane, including that portion of the disk coincident with the axis of rotation and the disk has a thickness which increases progressively in a radially inward direction from the peripheral edge, including that portion of the disk between the target and the mechanism for coupling, to counteract a radially inward increase in the disk upon high speed rotation of the disk.
    Type: Grant
    Filed: May 9, 1989
    Date of Patent: April 24, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Takahashi, Kenichi Takahara
  • Patent number: 4914684
    Abstract: A bearing retainer for mounting for a bearing in an X-ray tube, the X-ray tube having a rotating anode supported on an anode shaft held within a hollow anode stem, the retainer being slidably fitted into a hollow anode stem to hold one bearing coaxially with the anode shaft and to permit axial motion of the bearing so held, where the sliding surface of the bearing retainer is coated with titanium carbide, and wherein the bearing retainer includes a bearing flange not coated with titanium carbide which may be swaged around the outer race of the bearing to hold the bearing.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: April 3, 1990
    Assignee: General Electric Company
    Inventor: Kamleshwar Upadhya
  • Patent number: 4912739
    Abstract: A microfocus X-ray tube having a rotating anode wherein X-ray are generated by electron beam bombardment of the anode and wherein the electron beam is bent as by a magnetic field to impinge on a selected surface of the anode.
    Type: Grant
    Filed: September 21, 1987
    Date of Patent: March 27, 1990
    Inventor: Mortimer E. Weiss
  • Patent number: 4896341
    Abstract: Disclosed herein is an X-ray lithography system having a long life target. The life of the conventional target in X-ray generating systems for use in X-ray lithography systems is increased by providing means by which a single laser pulse can be provided to the same spot a plurality of times. In addition, new target designs are provided which are mechanically moved to allow laser pulses to be provided to adjacent points over a large surface area. One type of target is a cylindrical drum which is helically rotated to allow the laser pulse to intersect at all points along the helix of the drum. A second type of long life target is a long continuous strip in which a strip is moved from a feed reel to a take-up reel. The strip may be within a cassette.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: January 23, 1990
    Assignee: Hampshire Instruments, Inc.
    Inventors: James M. Forsyth, Robert D. Frankel
  • Patent number: 4894850
    Abstract: The invention relates to the elimination of streak-like artefacts in slit radiography which are caused by an axial excursion of the rotary anode X-ray tube used for making the radiographs. These streaks can be eliminated by adapting the speed of displacement of the X-ray beam, the number of revolutions per unit time of the anode and the intensity profile of the radiation beam to one another so that for each point the intensity modulation in the half-shade area, caused by the periodic displacement of the focal point, is compensated for.
    Type: Grant
    Filed: August 25, 1988
    Date of Patent: January 16, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Gottfried Frings, Walter Hillen, Ulrich Schiebel
  • Patent number: 4891831
    Abstract: A method for generating X-rays in an X-ray tube, comprises the steps of: rotating an X-ray target of a rotating anode, the X-ray target having a metal coated layer thereon; applying electron beams emitted from a cathode onto the metal coated layer of the X-ray target; and offsetting thermal deformation of the X-ray target due to the application of the electron beams by deformation of the X-ray target due to centrifugal force, thereby maintaining a position of the X-ray target in a direction of the application of the electron beams, at a room temperature of the X-ray target, thus generating the X-rays.
    Type: Grant
    Filed: July 21, 1988
    Date of Patent: January 2, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Akira Tanaka, Satoshi Shimada, Kazuji Yamada, Yusaku Nakagawa, Motohisa Nishihara, Tadahiko Miyoshi, Noboru Baba, Hiromi Kagohara, Ichiro Inamura
  • Patent number: 4891832
    Abstract: An x-ray tube has an evacuated housing with a cathode and a rotating anode therein, the rotating anode including a drive shaft normally supported during operation by a magnetic bearing arrangement, but having mechanical bearings attached to the housing by which the shaft is supported if the anode "drops" during operation. A disengageable contact is provided which, when closed, completes a circuit for supplying high voltage to the anode. A displaceable actuator extends into the evacuated housing for making and breaking the contact, the actuator being sealed air-tight within the housing by a spring bellows. The actuator has a guide element disposed outside of the evacuated housing, which permits the guide element to be lubricated as needed. A locking element is provided which is engageable with the guide element to hold the anode shaft, and thus the anode, in place against the mechanical bearings during transport of the x-ray tube.
    Type: Grant
    Filed: June 23, 1988
    Date of Patent: January 2, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hans Ebersberger
  • Patent number: 4878235
    Abstract: Several different embodiments of high-intensity rotating-anode X-ray are shown which use a liquid or fluid-cooled rotating-anode. No ferrofluid-type rotating joints or O-ring gasket-type seals are required so that the interior of the tube maintains a high vacuum without pumping. A bellows permits mechanical coupling to interior structures of the tube while providing a completely vacuum tight enclosure. All joints may be hard soldered or brazed together so the entire system can be baked at a high temperature during pumpdown.
    Type: Grant
    Filed: February 25, 1988
    Date of Patent: October 31, 1989
    Assignee: Varian Associates, Inc.
    Inventor: Weston A. Anderson
  • Patent number: 4852140
    Abstract: A structure for suppressing arcing in electric current carrying anti-friction bearings operating in a vacuum environment is disclosed having opposed spaced-apart surfaces forming an effective capacitor in parallel with the bearings responsive to temperature to reduce arcing which would otherwise result from current interruption in the bearings.
    Type: Grant
    Filed: June 11, 1987
    Date of Patent: July 25, 1989
    Assignee: Siemens Medical Systems, Inc.
    Inventor: Mark Dax
  • Patent number: 4845732
    Abstract: The invention relates to an apparatus and to a process for producing bremsstrahlung. This apparatus comprises in a ferromagnetic member a circular cavity containing electrons rotated on a circular path under the action of a magnetic field induced by the ferromagnetic member and by means for inducing a magnetic field. The apparatus also comprises a circular target partly located outside the cavity and rotating in a plane perpendicular to that of the path of the electrons. The end of the target periodically traverses said path in order to interact periodically with the electrons on their path, so as to produce bremsstrahlung. Means are provided for varying the magnetic field in the cavity and are synchronized with the interaction period of the target on the electrons and are connected to the induction means.Application to all fields requiring the production bremsstrahlung.
    Type: Grant
    Filed: February 10, 1987
    Date of Patent: July 4, 1989
    Inventor: Roche Michel
  • Patent number: 4821305
    Abstract: The average power capacity of a rotating-anode X-ray generator tube is limited by the slow radiation cooling of the anode. The invention removes this limitation by rotating the entire vacuum envelope so the heat can be conducted directly to the air or to a circulating liquid. The cathode and anode are made as figures of revolution about the axis. A stationary source of X-rays is produced by focusing a stationary spot of the light onto a rotating photocathode. The photoelectrons are drawn off and focused onto a stationary spot on the rotating anode, to produce a stationary source of X-rays.
    Type: Grant
    Filed: June 9, 1988
    Date of Patent: April 11, 1989
    Assignee: Varian Associates, Inc.
    Inventor: Weston A. Anderson
  • Patent number: 4819259
    Abstract: A rotary anode type X-ray apparatus includes an arithmetic unit for calculating the optimum number of revolutions of the anode, on the basis of the previously measured and stored temperature-characteristic data of the X-ray tube, at least one of the tube voltages applied to the X-ray tube, the X-ray radiation time, and the tube current. According to frequency of revolution data derived from the arithmetic unit, the motor controller drives the motor to rotate the rotary anode at an appropriate number of revolutions. This number is determined by the X-ray tube drive conditions, including the tube current.
    Type: Grant
    Filed: September 19, 1986
    Date of Patent: April 4, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shigeru Tanaka
  • Patent number: 4802196
    Abstract: A composite target for an x-ray tube has a graphite substrate portion and a metal portion, the two portions being bonded together by a platinum brace. A tantalum wetting agent layer on the graphite acts to improve the bond by causing the platinum to better wet the graphite portion.
    Type: Grant
    Filed: December 31, 1986
    Date of Patent: January 31, 1989
    Assignee: General Electric Company
    Inventors: Thomas C. Tiearney, Jr., William D. Love, David K. Moorman
  • Patent number: 4800581
    Abstract: An X-ray tube is provided with a target that radiates primarily the characteristic X-ray of molybdenum. The target has an electron focal area of molybdenum base alloy containing molybdenum as a major component, and at least one of titanium and a combination of potassium oxide and silicon dioxide.
    Type: Grant
    Filed: October 22, 1987
    Date of Patent: January 24, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaji Kujirai, Yoshio Fukuhara
  • Patent number: 4799250
    Abstract: The invention pertains to a rotating anode with graphite for an X-ray tube in which the quality of the bond with the graphite is considerably improved in comparison with the prior art, through the use of a bonder element comprising beryllium.
    Type: Grant
    Filed: January 14, 1987
    Date of Patent: January 17, 1989
    Assignee: Thomson-CGR
    Inventors: Jean M. Penato, Emile Gabbay, Yves Debrouwer
  • Patent number: 4799249
    Abstract: A self-cleaning rotating anode x-ray source comprising an evacuable housing, a rotatable cylindrical anode within the housing, a source of electrons within the housing which electrons are caused to impinge upon the anode to produce x-rays, and means for ionizing residual particles within the housing and accelerating such ions so as to impinge upon the anode to sputter impurities from the surface thereof.
    Type: Grant
    Filed: June 2, 1987
    Date of Patent: January 17, 1989
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Arvydas P. Paulikas
  • Patent number: 4788705
    Abstract: A high-intensity X-ray source generates significant heat at the anode. To help dissipate this heat, the anode is often rotated in the vacuum. Heat must still be radiated from the anode to the exterior walls. An improved X-ray source incorporates the anode in the walls of the vacuum chamber and rotates the entire chamber. The heat is then easily conducted to the exterior where it may be dissipated by connection or forced air cooling.
    Type: Grant
    Filed: January 21, 1987
    Date of Patent: November 29, 1988
    Assignee: Varian Assoicates, Inc.
    Inventor: Weston A. Anderson
  • Patent number: 4780900
    Abstract: A radiological device is provided of the type comprising a radiogenic tube with magnetic bearings, said radiogenic tube being contained in a sheath as well as electronic means for controlling said magnetic bearings.
    Type: Grant
    Filed: April 23, 1986
    Date of Patent: October 25, 1988
    Assignee: Thomson-CGR
    Inventors: Emile Gabbay, Andre Plessis
  • Patent number: 4780902
    Abstract: Rotary anodes for X-ray tubes are provided having improved thermal stability. The rotary anodes are comprised of a basic body made of molybdenum alloy comprising about 0.1 to 15% by weight hafnium, about 0.1 to 15% by weight zirconium, about 0.01 to 1.0% by weight carbon and the balance molybdenum.The alloy according to the invention has a low tendency of cracking distortion, and/or surface roughening, even with focal track zones made of tungsten and tungsten alloys and even at operating temperatures exceeding the currently normal values by up to about 200.degree. C.
    Type: Grant
    Filed: June 20, 1986
    Date of Patent: October 25, 1988
    Assignee: Schwarzkopf Development Corporation
    Inventor: Ralf Eck
  • Patent number: 4769831
    Abstract: A rotating anode x-ray tube has an anode magnetically seated in a housing in non-contacting fashion. For non-contacting transmission and dissipation of the anode current, a hollow cylindrical rotor of the anode is provided with ribs on its interior surface. A stationary hollow cylinder is disposed inside of the rotor, the stationary hollow cylinder being also provided with ribs in registry with the ribs on the interior of the rotor, and being connected to the anode lead. Current is thereby transferred from the stationary cylinder to the rotating hollow cylinder by corona discharge.
    Type: Grant
    Filed: September 29, 1986
    Date of Patent: September 6, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Karlheinz Broenner
  • Patent number: 4736400
    Abstract: A rotatable x-ray target assembly and process for manufacturing the same is provided for an x-ray tube. The x-ray target assembly comprises an x-ray target member having an opening disposed therethrough and a support member having: a mounting surface disposed transversely to the axis of rotation, a lower surface of the target member being disposed on the mounting surface; and, a threaded stem extending from said mounting surface through the opening of the target member. The support member also comprises a nut adapted to receive the threaded stem, the nut engaging an upper surface of the target member. The target member is secured to the support member by brazing material disposed between the lower surface of the target member and the mounting surface, a first portion of the brazing material being diffused into the target member and a second portion of the brazing material being diffused into the mounting surface of the support member.
    Type: Grant
    Filed: January 9, 1986
    Date of Patent: April 5, 1988
    Assignee: The Machlett Laboratories, Inc.
    Inventors: Thomas J. Koller, Steven Tavoletti
  • Patent number: 4731805
    Abstract: A rotary anode for an X-ray tube is in the form of a disc (1) the surface of which has, at least partially, a blackening coating (2). The latter is in the form of a sintered porous composition of titanium grains, mainly of the dendritic structure, of a size from 0.5 to 150 .mu.m, and at least one high-melting metal having a melting point above 2500.degree. C., the quantity the high-melting metal in the composition being from 5 to 60% by mass.
    Type: Grant
    Filed: January 28, 1986
    Date of Patent: March 15, 1988
    Inventors: Maiya F. Boyarina, Vladimir G. Vildgrube, Jury S. Sergeev, Oleg V. Filatov, Lev G. Andruschenko, Jury N. Zelenov, Valery N. Kupriyanov, Elena I. Taubkina
  • Patent number: 4679220
    Abstract: An evacuated envelope is formed with a portion of larger diameter and tubular portions extending along the axis on both sides of the portion of larger diameter in opposite directions. A target with a rotatable anode is arranged in the portion of larger diameter. A pair of shafts arranged on the tube axis and fixed on both sides of this target are arranged in the tubular portions. Each shaft has at least one flange of insulating material on the side facing the target and on its periphery is provided with a metal tube constituting a rotor of a magnetic bearing. On the outermost side of the tubular portion there are arranged a magnetic field generating device and a magnetic drive device that rotates the rotatable anode target.
    Type: Grant
    Filed: January 17, 1986
    Date of Patent: July 7, 1987
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Katsuhiro Ono
  • Patent number: 4675891
    Abstract: The invention relates to an X-ray apparatus with focus position control, the focus being formed on the anode of an X-ray tube with magnetic bearings. The X-ray apparatus comprises a focus position sensing device cooperating with electronic means associated with the magnetic bearings, in order to control the position of the focus by displacing a rotor under the action of the magnetic bearings.
    Type: Grant
    Filed: June 25, 1985
    Date of Patent: June 23, 1987
    Assignee: Thomson-CGR
    Inventors: Andre Plessis, Jacques Leguen
  • Patent number: 4670895
    Abstract: The present invention relates to an X-ray tube with a rotary anode and to a process for fixing a rotary anode to a support shaft contained in such a tube. The rotary anode is fixed to the support shaft with the aid of a deformed element, positioned between the rotary anode and the support shaft, concentrically to the latter, and acting in the manner of a stuffing box.
    Type: Grant
    Filed: June 25, 1985
    Date of Patent: June 2, 1987
    Assignee: Thomson-CGR
    Inventors: Jean M. Penato, Paul Hery, Claude Bouhnik
  • Patent number: 4651336
    Abstract: In an X-ray tube comprising a rotating anode mounted on magnetic bearings, the flow of anode current within the tube takes place without any contact by means of a stationarily fixed hollow anode in which is placed a cathode coupled rotationally to the rotating anode. The hollow anode is associated with heating means and the cathode is heated by thermal radiation within the hollow anode.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: March 17, 1987
    Assignee: Thomson-CSF
    Inventors: Jacques Le Guen, Andre Plessis
  • Patent number: 4641332
    Abstract: The bearing in an X-ray tube comprising a liquid metal lubricated helical-groove bearing is provided with a push-pull bearing at one or both end faces of a bearing member. Consequently, the bearing member need not be further secured so that, notably in the case of suitable cooling of the anode disc and the bearing, extremely precise positioning of the radiation object point in the tube can be achieved.
    Type: Grant
    Filed: November 2, 1984
    Date of Patent: February 3, 1987
    Assignee: U.S. Philips Corporation
    Inventor: Jan Gerkema
  • Patent number: 4635283
    Abstract: Mounting for a rotary anode in an x-ray tube. A radially outer rotor sleeve, constituting the rotor of an electric motor, has an anode disc connected centrally thereof. A radially inner, supporting sleeve is telescoped within the rotor sleeve and is spaced radially therefrom. A central shaft extending longitudinally of the rotor sleeve and a further sleeve intermediate between the radially inner and outer sleeves has an anti-friction bearing with inner and outer races mounted on its respective ends, the inner race of each bearing being connected to the shaft and the outer race of each bearing being connected to the intermediate sleeve which is disposed coaxially of the rotor sleeve, the intermediate sleeve, and the shaft, and between and spaced from the shaft and the supporting sleeve. The intermediate sleeve is prevented from axial movement with respect to the supporting sleeve.
    Type: Grant
    Filed: March 26, 1984
    Date of Patent: January 6, 1987
    Assignee: ZVL Vyzkumny ustav pro valiva loziska Brno
    Inventors: Frantisek Starek, Vilem Machacek, Pavel Manhalter
  • Patent number: 4608707
    Abstract: The invention relates to a rotating anode X-ray tube provided with a charge flow device, in which the anode current of the tube is established between an emitter coupled in rotation to the rotating anode, as well as a fixed collector. The latter is electrically connected to high voltage and the emitter is electrically connected to the rotating anode, having at least one part with a tapered end constituting an electron emissive zone. These electrons are trapped by the collector, so as to establish the anode current of the tube without any material contact between the emitter and the collector. The invention is applicable to radiology in general and more specifically to medical diagnosis.
    Type: Grant
    Filed: June 22, 1984
    Date of Patent: August 26, 1986
    Assignee: Thomson-CGR
    Inventors: Emile Gabbay, Andre Plessis
  • Patent number: 4577340
    Abstract: An all metal and ceramic high vacuum rotary anode X-ray tube adapted for mounting on a gantry of a rotational type CT scanner. The evacuated region where X-rays are generated is maintained at about 10.sup.-7 Torr. Vacuum sealing about the rotating shaft of the anode is provided by a magnetic fluid. No bearings are utilized within the evacuated region. Large, long wearing ball bearings that transmit rotation through the vacuum seal are provided about the shaft outside of the high vacuum region where conventional lubricants may be applied. Circulating coolant is applied internally through the anode assuring continual operation of the tube without the need for frequent cool-down waits.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: March 18, 1986
    Assignee: Technicare Corporation
    Inventors: Roland W. Carlson, Edward A. Blaskis
  • Patent number: 4574388
    Abstract: An x-ray tube anode formed of a dispersion-strengthened molybdenum alloy which is not compatible with a stem of a different material for purposes of diffusion bonding, includes an integral core insert composed of a substantially pure molybdenum alloy. The insert is compatible with both the adjoining materials and allows for a diffusion bonding of the anode to the stem.
    Type: Grant
    Filed: May 24, 1984
    Date of Patent: March 4, 1986
    Assignee: General Electric Company
    Inventors: John H. Port, Dennis G. Kukoleck, Robert M. Guezuraga
  • Patent number: 4573185
    Abstract: A tungsten focal track is placed on a graphite substrate in such a manner as to reduce off focal spot radiation while maintaining a fixed focal spot size. The radial width of the focal tract is made smaller than that of the electron beam from the cathode such that the electron beam overlap will allow for misalignments between the electron beam and the focal track without affecting the focal spot size or location.
    Type: Grant
    Filed: June 27, 1984
    Date of Patent: February 25, 1986
    Assignee: General Electric Company
    Inventors: Brian D. Lounsberry, Robert W. Meade
  • Patent number: 4569070
    Abstract: The rotor that carries the target in a rotating anode x-ray tube is carried on a shaft that is journaled in axially spaced apart ball bearings. The outer and inner races of the bearings have curved grooves presented toward each other and there are a plurality of balls in the grooves. A preloaded spring is interposed between corresponding races of the bearings for applying oppositely directed axial forces to them. The grooves are so shaped and the clearance between the balls and groove surfaces is such that when the axial force is applied, one race shifts axially relative to the other in which case each ball has two points of contact, one point at which the ball contacts the surface of the groove in the outer race on one side of a plane transverse to the shaft axis and another point where the ball contacts the surface of the groove in the inner race on the other side of the plane.
    Type: Grant
    Filed: September 19, 1983
    Date of Patent: February 4, 1986
    Assignee: General Electric Company
    Inventors: Thomas E. Schubert, John C. Clark
  • Patent number: 4563769
    Abstract: In an X-ray generator device a target member emitting X-rays by electron bombardment is arranged in a rod-shaped tubular probe and is provided with a conically tapering front part facing a comparatively narrow aperture in a controlling electron beam diaphragm for the purpose of forming a substantially punctiform radiation source. The position of the target member is adjusted by securing the rod-shaped target member at a part of its length reckoned from its opposite, rearmost end in a central bore of an oblong cylindrical target carrier positioned coaxially in the probe, said target carrier being only at its foremost end connected with the wall of the probe, thereby allowing fine adjustment of the target member with respect to said aperture by displacement of said opposite end of the target carrier in a radial plane in the probe, e.g. by means of wedge means formed as adjusting screws in the annular channel between the target carrier and the inner wall of the probe.
    Type: Grant
    Filed: December 21, 1982
    Date of Patent: January 7, 1986
    Assignee: Andrex Radiation Products A/S
    Inventor: Jens U. Madsen
  • Patent number: 4562587
    Abstract: An X-ray tube having a rotary anode which is accommodated in a vacuum-tight housing so as to be rotatable by means of at least one spirally grooved bearing. The mutually cooperating surfaces of the bearing consist essentially of Mo or of an alloy of Mo and W and are effectively wetted by a Ga-alloy serving as a bearing lubricant. In order to extend the life of the X-ray tube, 1 to 4% by weight of Ag and/or Cu are added to the Ga-alloy, as a result of which the formation of crystalline compounds is inhibited.
    Type: Grant
    Filed: December 16, 1983
    Date of Patent: December 31, 1985
    Assignee: U.S. Philips Corporation
    Inventors: Jan Gerkema, Anton K. Niessen, Jozef B. Pelzer
  • Patent number: 4545064
    Abstract: A mounting system for securing a rotating anode of an x-ray tube against axial movement locates a bearing on a stud projecting from a tube end wall and secures the bearing on the stud by means of a threaded fastener which is accessed through a central bore of the rotating anode assembly prior to closure of the tube vacuum envelope.
    Type: Grant
    Filed: October 28, 1983
    Date of Patent: October 1, 1985
    Assignee: Litton Systems, Inc.
    Inventor: Heinrich F. Klostermann
  • Patent number: 4531227
    Abstract: The invention provides a rotary anode which has a graphite body having a plurality of radial slits and a target layer adhered to the upper surface of the graphite body. The target layer is a single layer of tungsten or a tungsten alloy, or a composite layer consisting of the single layer and a molybdenum layer. In the manufacturing process and in use of the rotary anode, a thermal stress which occurs in the graphite body is decreased, thus preventing cracking of the graphite body. The invention also provides a method for manufacturing the rotary anode.
    Type: Grant
    Filed: September 23, 1982
    Date of Patent: July 23, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Yoshio Fukuhara, Hideo Koizumi
  • Patent number: 4519093
    Abstract: A rotary anode X-ray tube comprises a support frame disposed inside a glass bulb, a rotary anode fixed to a shaft portion of the support frame, a rotating shaft attached to the support frame coaxially with the shaft portion, a support member having a cylindrical portion concentrically surrounding the rotating shaft at a given space therefrom, a double tube concentrically disposed between the rotating shaft and the cylindrical portion and fixed to the cylindrical portion, first and second bearings concentrically disposed between the auxiliary tube and the rotating shaft at given spaces therefrom, and a coil spring for elastically pressing one race of one of the bearings along said rotating shaft, the other race of which is fixed.
    Type: Grant
    Filed: February 21, 1984
    Date of Patent: May 21, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Teruo Kurihara, Takeshi Oowa
  • Patent number: 4504965
    Abstract: In the case of tubes with magnetically mounted anodes, it is difficult to obtain an adequately stable mounting of the anode shaft for all stresses to be expected, in particular, in the case of tilting and pivoting. To this end, the disclosure provides that magnetically conductive pole pieces are inserted in the wall of the tube envelope at the locations at which magnets are exteriorly disposed which pole pieces are in magnetic coupling relation with the anode arrangement. The distances between the parts to be magnetically coupled can thereby be substantially reduced, so that there results--in relation to known magnetic bearings--a substantially more stable support-mounting of the rotary anode in the high vacuum envelope. The disclosure is, in particular, applicable in the case of X-ray tubes for utilization in medical X-ray technology.
    Type: Grant
    Filed: December 7, 1982
    Date of Patent: March 12, 1985
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hans Ebersberger