Close Proximity Seal (e.g., Contactless, Fluent, Etc.) Patents (Class 277/409)
  • Patent number: 6814356
    Abstract: A mount construction for a bearing seal is capable of easily and surely installing the bearing seal in a bearing and, after installation, developing a stable seal performance by suppressing an extracting force. The bearing seal, formed by disposing an elastic member having a lip part on one side face of a reinforcement ring, is press-fitted into a ring body or radially reduced ring body in a state where the lip part is bent in a direction away from the outer peripheral edge of the reinforcement ring on the elastic member side of the bearing seal. While maintaining this state, the bearing seal is extruded from the inside of the ring body or the radially reduce ring into the bearing with care so that the lip part is not caught between the reinforcement ring and the bearing is installed on the bearing.
    Type: Grant
    Filed: May 14, 2002
    Date of Patent: November 9, 2004
    Assignee: Uchiyama Manufacturing Corp.
    Inventor: Koji Esumi
  • Patent number: 6811154
    Abstract: An annular finger seal is adapted to be interposed between a high pressure upstream region and a lower pressure downstream region to provide noncontact sealing along a rotatable member. The finger seal comprises axially juxtaposed downstream and upstream finger elements, each having integrally spaced fingers. The downstream fingers each have a lift pad, whereas the upstream fingers lack a pad. Each pad extends in a downstream direction. Each upstream finger is spaced from the rotating member a greater distance than each pad. Upon sufficient rotational speed of the rotating member, each pad is operative to lift and ride on a thin film of fluid intermediate the rotating member and the pad.
    Type: Grant
    Filed: February 8, 2003
    Date of Patent: November 2, 2004
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Margaret P. Proctor, Bruce M. Steinetz
  • Publication number: 20040155410
    Abstract: An annular finger seal is adapted to be interposed between a high pressure upstream region and a lower pressure downstream region to provide noncontact sealing along a rotatable member. The finger seal comprises axially juxtaposed downstream and upstream finger elements, each having integrally spaced fingers. The downstream fingers each have a lift pad, whereas the upstream fingers lack a pad. Each pad extends in a downstream direction. Each upstream finger is spaced from the rotating member a greater distance than each pad. Upon sufficient rotational speed of the rotating member, each pad is operative to lift and ride on a thin film of fluid intermediate the rotating member and the pad.
    Type: Application
    Filed: February 8, 2003
    Publication date: August 12, 2004
    Applicant: National Aeronautics and Space Administration
    Inventors: Margaret P. Proctor, Bruce M. Steinetz
  • Publication number: 20040145119
    Abstract: In case that some trouble occurs in exhaust pump or in pipe, internal pressure of groove comes closer to atmospheric pressure owing to leak-in of air, because the groove adjoins groove opened to atmospheric air. However, the internal pressures of grooves are maintained at negative value. Thus, difference in pressure between the top and bottom surfaces of moving block is generated. Further, the gap between the moving block and the intermediate block decreases. Consequently, the deterioration in the degree of vacuum in the process chamber can be retarded. During retarded time, measures to protect an object to be processed, such as operation of tightly sealing the object can be taken. Further, in case that the system recovers, time required to operate turbo-molecular pump for sucking the inside of the process chamber is reduced to a short time. Therefore, the processing can be quickly resumed.
    Type: Application
    Filed: September 30, 2003
    Publication date: July 29, 2004
    Applicant: NSK LTD.
    Inventors: Tsuyoshi Nakamura, Nobuhito Saji
  • Patent number: 6758477
    Abstract: A gas turbine engine aspirating face seal includes rotatable and non-rotatable engine members and a leakage path therebetween. Annular generally planar rotatable and non-rotatable gas bearing face surfaces are operably associated with the rotatable and non-rotatable engine members respectively and are circumscribed about and generally perpendicular to a centerline axis. A substantially fully annular pull off biasing element is operably disposed for urging the non-rotatable gas bearing face surface axially away from the rotatable gas bearing face surface and circumscribed about the centerline axis. The pull off biasing element may be at least one wave spring or one bellville washer. The non-rotatable gas bearing face surface may be on a face seal ring mounted on a translatable cylindrical piston which is axially movable and supported by the non-rotatable engine member.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: July 6, 2004
    Assignee: General Electric Company
    Inventors: John C. Brauer, Robert J. Albers
  • Patent number: 6746019
    Abstract: A seal assembly (10) includes a first seal element (12) defining a fist sealing surface (14); displacement means including at least one electromagnet (20) operatively coupled with the first seal element (12), the displacement means being operable to displace the first seal element (12) via the, or each, electromagnet (20); and a second seal element defining a second sealing surface (28) associated with the first sealing surface (14), the first and second seal elements providing a seal. The invention extends to a combination comprising a gas turbine and a seal assembly. The invention further extends to a method of controlling a spacial relationship between respective sealing surfaces of two seal elements.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: June 8, 2004
    Assignee: Eskom
    Inventors: Johannes Jacobus Liebenberg, Johan Francois De Villiers
  • Patent number: 6742782
    Abstract: A seal of non-hermetic design for installation between two components which can move relative to one another, includes a multiplicity of flexurally elastic sealing elements which each have an end connected fixedly to a seal-bearing device and a free, angled end with the point directed toward the surface of the one component, the seal-bearing device being connected fixedly to the other component and supporting the angled ends of the sealing elements at least on one side. The sealing elements are designed as thin-walled, angled spring leaves and are arranged parallel next to one another and in at least two layers one above the other with alternate overlapping.
    Type: Grant
    Filed: April 3, 2001
    Date of Patent: June 1, 2004
    Assignee: MTU Aero Engines GmbH
    Inventor: Stefan Beichl
  • Patent number: 6722657
    Abstract: Disclosed is a labyrinth seal assembly for sealing an annular gap defined between a bore of a housing and an outer surface of a cylindrical shaft, wherein the housing and shaft are relatively movable. The seal assembly includes radially inner and radially outer shield rings. The radially inner shield ring has an inner surface which is adapted and configured for support by the shaft. The radially outer shield ring is partially disposed within the sealing channel of the inner shield ring. The outer shield ring includes a casing member, foam seal elements, and a shield element retainer. The foam seal elements depend radially inward into the sealing channel so as to form a circuitous sealing labyrinth therein. The seal elements are formed preferably from polyurethane. A highly viscous fluid is disposed within the circuitous sealing labyrinth.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: April 20, 2004
    Assignees: Stemco LLC, The Timken Company
    Inventors: Charles Robin Hood, Donald G. Wells, Mark N. Gold, Richard Borowski
  • Patent number: 6719296
    Abstract: A face seal assembly is provided having an annular seal body mounted in an axially moveable relationship to a seal support structure. A piston ring is disposed between the annular seal body and the seal support structure forming a secondary seal. A first locator spring, which is an annular wave spring, is disposed between said seal support structure and the piston ring to urge the piston ring in an axial direction. Optionally, a second locator spring, also a wave spring, may be disposed between the piston ring and the seal support structure for urging the piston ring in a radial direction.
    Type: Grant
    Filed: July 12, 2002
    Date of Patent: April 13, 2004
    Assignee: General Electric Company
    Inventors: John Christopher Brauer, Christopher Charles Glynn, Wu-Yang Tseng, Jerry Lynn Cabe
  • Patent number: 6715765
    Abstract: A sealing structure of a ball bearing is disclosed wherein a seal or a shield is provided on at least one side of the ball bearing, the ball bearing allowing rotation of either an outer ring or an inner ring. A large number of blades extend radially along an outer surface of the seal or shield provided on one side of the ball bearing. An annular plate may be mounted on a shaft with the inner ring fitted thereon at a position relatively close to the blade projections. Plural through holes may be formed circumferentially on or near an inner peripheral edge of the annular plate. Thus, a simple structure effectively prevents fluid from flowing or leaking through the ball bearing and also prevents leakage of grease from the ball bearing.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: April 6, 2004
    Assignee: Minebea Co., Ltd.
    Inventor: Shin-ichi Machida
  • Publication number: 20040046323
    Abstract: The present invention relates to a seal system for use in rotary machines. The seal system includes a first member and a second member forming an annulus, a high pressure region and a low pressure region in the annulus, and a liquid seal intermediate the first and second members and intermediate the high pressure region and the low pressure region for reducing gas leakage from the high pressure region to the low pressure region.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 11, 2004
    Inventor: Sean McCutchan
  • Publication number: 20040046324
    Abstract: A seal and method of making seals utilises folds in order to form creases in a length of material such that the creases reinforce individual seal elements or surfaces whilst perforations or slots in a seal edge allow air leakage from one side of the seal element or surface to the other. Thus, air pressurisation can take place between spaced seal elements or surfaces and this allows air flotation or riding of a rotating component relative to a static housing component. The perforations are typically graduated from the seal edge in order to provide the best pressurisation and air-riding effect for proximity or gap control between the sealing edge and the rotating component surface. The slots effectively provide flexibility to the sealing edge such that the seal component emulates a brush seal.
    Type: Application
    Filed: July 31, 2003
    Publication date: March 11, 2004
    Inventor: Alison J. McMillan
  • Patent number: 6698762
    Abstract: A lubricant leakage stop is provided on the shaft of a rotary device in the form of an annular groove in the shaft. In one embodiment the annular groove is formed with an annular inner surface at the bottom of the groove and with an annular intermediate surface positioned between two portions of the annular inner surface. The intermediate surface has a larger diameter dimension than the two inner surface portions on the axially opposite sides of the intermediate surface. The intermediate surface also has a smaller diameter dimension than that of the two portions of the shaft outer surface on axially opposite sides of the groove. In a second embodiment, the annular groove is formed with an annular inner surface that tapers from the bottom of the groove outwardly to the outer surface of the shaft on one side of the groove.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: March 2, 2004
    Assignee: Emerson Electric Co.
    Inventors: Barry M. Newberg, Gary W. Borcherding
  • Patent number: 6682077
    Abstract: A disc turbine has a rotor assembly of spaced apart discs with at least one disc equipped with an annular labyrinth seal whose grooves interdigitate with a corresponding labyrinth seal mounted in the sidewall of the rotor housing. A pattern of aligned through holes in the rotor housing and the rotor housing seal assist in the axial and concentric alignment of the rotary assembly with respect to the stationary assembly, and the inspection of same, and provide access through at least one sensing port to working fluid proximal to the seal entrance.
    Type: Grant
    Filed: February 13, 2002
    Date of Patent: January 27, 2004
    Inventor: Guy Louis Letourneau
  • Patent number: 6679501
    Abstract: A motor or bearing which incorporates the use of a capillary seal adjacent a bearing race between the shaft and surrounding hub or housing. The seal may take a plurality of forms, including a straight capillary seal; a seal formed between the housing and a seal ball having different radius of curvatures (preferably with the housing internal surface having a larger radius); or a centrifugal capillary seal comprising a male cone supported on a fixed or rotating shaft, and a female cone supported on a housing. The use of a capillary seal rather than ferrofluid seal should also provide a reduction in resistance across the seal gap compared to a ferrofluid seal.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: January 20, 2004
    Assignee: Seagate Technology LLC
    Inventors: Robert M. Pelstring, Raquib U. Khan, Klaus Kloeppel, Alan L. Grantz, Norbert S. Parsoneault, Marten F. Byl, Hans Leuthold
  • Patent number: 6655696
    Abstract: A seal carrier is provided for a rotary machine wherein the seal carrier comprises a packing ring coupled to a seal and wherein the packing ring comprises a channel disposed therein. In addition, a displacement apparatus is disposed in the channel for radially positioning the seal to control a flow of a fluid in a fluid path.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: December 2, 2003
    Assignee: General Electric Company
    Inventors: Biao Fang, Norman Arnold Turnquist, Hamid Reza Sarshar, Mahmut Faruk Aksit, Mark Edward Burnett, Frederick George Baily, Mehmet Demiroglu
  • Publication number: 20030201609
    Abstract: A unitized seal assembly for use with roller or ball bearing assemblies is disclosed. The unitized seal assembly includes, among other things, a radially outer ring and a radially inner deflector ring. The outer ring includes a first shield element which defines a first sealing face. The radially inner deflector ring includes a second shield element which defines a second sealing face. The second sealing face is dimensioned and configured so as to correspond to the first sealing face such that when the first shield element is positioned in non-contacting proximity to the second shield element, a circuitous sealing labyrinth is formed between the first sealing face and the second sealing face.
    Type: Application
    Filed: April 26, 2002
    Publication date: October 30, 2003
    Inventors: Charles Robin Hood, Donald G. Wells, Mark N. Gold
  • Publication number: 20030168815
    Abstract: A hydraulic seal arrangement 5 between two shafts 1, 2 rotating relatively to each other, particularly in the same sense of rotation, of especially a gas turbine engine, where the radially outer shaft 2 has an annulus 5a extending radially outwards on its circumference into which the radially inner shaft 1 projects with a fin 5b that extends radially outwards on its circumference, said annulus 5a can be filled siphon-fashion through an inlet area 5d under centrifugal effect with a hydraulic fluid in the area of the free end of the fin 5b as the shaft(s) 1, 2 rotate(s), with an opening 7 branching off from an annulus area 5e for the discharge of hydraulic fluid, the annulus 5a being formed by a first outer shell part 8 and a second outer shell part 9 situated on the shaft 2.
    Type: Application
    Filed: January 13, 2003
    Publication date: September 11, 2003
    Inventor: Detlef Rensch
  • Patent number: 6592127
    Abstract: An air purged shaft seal assembly has a seal housing fixedly securable to a stationary support and having a circular aperture through which a shaft can pass. The seal housing has an internal annular surface defining the circular aperture, the internal annular surface having a first annular portion for engaging an outer surface of an annular sealing member and a second annular portion shaped to partially form an air receiving chamber. The seal housing has a passage for supplying air under pressure from an external source thereof to the air receiving chamber. A sleeve mountable on the shaft for sliding movement therealong, the sleeve having an external peripheral surface with a first peripheral portion co-operable with the first annular portion of the internal annular surface of the seal housing to receive the annular sealing member therebetween and a second peripheral portion co-operable with the second annular portion of the internal annular surface of the seal housing to form the air receiving chamber.
    Type: Grant
    Filed: January 23, 2002
    Date of Patent: July 15, 2003
    Assignee: Phlaver Inc.
    Inventors: Arnold B. Flower, Bernard Teichroeb
  • Patent number: 6590747
    Abstract: A sealed micro-actuator device for positioning a slider in a disc drive comprises a micro-actuator body, which includes a stator, a rotor, and a motor for moving the rotor with respect to the stator. The micro-actuator device includes means for sealing the micro-actuator body to prevent debris from reaching the motor. In a preferred embodiment, the means for sealing comprises a plurality of cavities formed in the micro-actuator body and an injection molded polymer seal with a plurality of protrusions that extend into the plurality of cavities. A first subset of the plurality of protrusions make contact with the stator, thereby holding the means for sealing in place. A second subset of the plurality of protrusions extend into cavities formed in the rotor. The second subset of protrusions does not contact the rotor.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: July 8, 2003
    Assignee: Seagate Technology, LLC.
    Inventors: Zine-Eddine Boutaghou, Wayne A. Bonin
  • Publication number: 20030122316
    Abstract: In a gas turbine having a chordal hinge seal between an inner rail of each nozzle segment and an annular axially facing sealing surface of a nozzle support ring, a supplemental seal is disposed between the support ring and inner rail of the nozzle segment on a high pressure side of the chordal hinge seal. The supplemental seal includes a pair of sheet metal shims overlaid by a woven metallic cloth supported by a bracket secured to the nozzle support ring. The radially outer end of the cloth seal bears against a back side of the inner rail. The shims of the legs of the supplemental seal are slit along their distal margin and staggered in a circumferential direction relative to one another to provide flexibility and effective sealing engagement with the inner rail.
    Type: Application
    Filed: December 28, 2001
    Publication date: July 3, 2003
    Inventors: Mahmut Faruk Aksit, Ahmad Safi, Abdul-Azeez Mohammed-Fakir
  • Patent number: 6572113
    Abstract: A seal assembly for co-operation with a shaft comprising a seal member which, in use, in a first position, forms a seal against the shaft, a seal housing for retaining the seal member, means for applying a radially inward force to the seal member and means for applying a radially outward force to the seal member so that, when the means for applying a radially outwards force is operated, the seal member is dilated to a second position thereby enabling the seal assembly and the shaft to be fitted and disassembled in conventional manner, when the means for applying a radially outward force is removed the means for applying a radially inward force to the seal member returns the seal member to the first position.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: June 3, 2003
    Assignee: Rolls-Royce plc
    Inventor: Ian C D Care
  • Patent number: 6561516
    Abstract: A stationary ferrofluidic seal for sealing a stationary shaft to a rotating hub. A formed magnetic is attached to the rotating hub, bounded by upper and lower members to form a shaped cavity. A stationary ring is attached to the shaft and extends into the cavity, which is filled with a conductive ferrofluid. The cavity has a uniform, concave cross section over at least part of its surface. The end of the stationary ring distal from the shaft is shaped so that in the region containing the fluid, the ring and cavity surface are equidistant from a set of points defining the seals “characteristic contour”.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: May 13, 2003
    Assignee: Seagate Technology LLC
    Inventors: Ram V. Pazhayannur, David D. Koester, John W. Elsing
  • Patent number: 6467773
    Abstract: A non-contacting seal which includes a stationary tooth that radially overlaps a tooth on a rotatable shaft, with the sealing action resulting from controlled clearance both radially between stationary tooth and the shaft, and axially between the stationary tooth and the shaft. The seal may also be in the form of a stationary tooth that is approximately in the same radial plane as a tooth on a rotatable shaft, with the sealing action resulting from both a controlled clearance gap between the two teeth and from the momentum of liquid traveling outward from the rotating tooth making it difficult for the liquid to turn to go axially through the gap between the rotating tooth and the stationary tooth. The seal may also comprise the combination of the two seals described above.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: October 22, 2002
    Assignee: Atlas Copco Comptec Inc.
    Inventor: John M. Rinaldo
  • Patent number: 6454270
    Abstract: A low leakage sealing system is provided between a steam pipe and a housing comprised of a pair of shells and a nozzle box movable relative to one another. The sealing system includes large and small diameter sealing rings engaging the pipe and shells or nozzle box and a secondary sealing element disposed between the sealing rings and one of the pipe and shells or nozzle box. The sealing elements comprise frustoconical elements having curved end surfaces forming primary seals with the sealing rings and the housing. In another form, the sealing system includes annular carrier elements having radially opening cavities for receiving sealing rings engageable with the pipe and housing, respectively. The carrier elements are axially spaced from a plurality of sealing rings to provide the low leakage sealing system.
    Type: Grant
    Filed: December 14, 2000
    Date of Patent: September 24, 2002
    Assignee: General Electric Company
    Inventors: Wei-Ming Chi, Norman Arnold Turnquist, Christopher Edward Wolfe, Mark Arne Florin, Mahmut Faruk Aksit
  • Patent number: 6390477
    Abstract: A bearing isolator seal having a shaft seal assembly that includes a stator housing comprising two components, an interior and an exterior component, the two stator housing components being selectively connectable, and axially positionable (relative to the radial faces of the rotor), disconnectable via screw threads on similar structures formed thereon to enable a perishable rotor component to be readily replaced with the stator components being reusable with a new rotor, the assembled stator housing, having an inner radially extending face with a pair of spaced concentric annular flanges of substantially frusto-conical shape extending from a larger diameter end that is fixed to the inner radially extending face to a smaller diameter free end, and a rotor having a peripherally extending radial flange that is fixed to a hub of the rotor and has a contact sealing surface that contacts the free end of the annular flanges of the stator housing.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: May 21, 2002
    Assignee: Garlock Inc
    Inventors: James Drago, Joel R. Shaw, Larry E. Strohm
  • Patent number: 6378874
    Abstract: An apparatus and method are provided for sealing and electrically coupling an outer surface 170 of a shaft 175 to an inner surface 165 of a hub 160 disposed about the shaft. The invention is particularly useful for spindle motors 155 used in disc drives 100. In one embodiment, a seal 185 having a pair of annular pole pieces 270a, 270b, coupled to opposite poles of a magnet 265 is positioned between the shaft 175 and the hub 160. A nonmagnetic, electrically conductive ring 275 electrically couples the pole pieces 270a, 270b to one another and to the hub 160. In one version, the electrically conductive ring 275 includes an annular disk 300 with tabs 305 projecting from the exterior radius. The disk 300 abuts one pole piece 270b and the tabs 305 are folded over to electrically couple to the other 270a.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: April 30, 2002
    Assignee: Seagate Technology LLC
    Inventor: Robin Francis Dorulla
  • Patent number: 6364317
    Abstract: This invention relates to an arrangement for sealing a closed chamber in which equipment is to be replaced and especially to a chamber in which equipment is to be replaced while the chamber is to be maintained closed. The arrangement includes a channel filled with a fluid, such as water, and a skirt arranged to extend into the fluid to form the seal. As the skirt extends down into the liquid, a portal space is formed at the opening in the chamber and the opening preferably includes a gate for closing the chamber from the portal space and the outside.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: April 2, 2002
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Tom Edward Estep, Ronald P. Hoffman, James R. Hunter, Jean Joseph Muller, Germain Schilz, Carl E. Vorhees, James M. Wiggins, Jean Francois Woll
  • Patent number: 6334616
    Abstract: A hard disk drive spindle motor has a hub, a drive shaft, and a bearing therebetween. The spindle motor also has a ferrofluid seal to prevent any incidental oil emissions from the bearing from entering the drive. A ferrofluid cap is mounted on the axial end of the spindle motor for sealing the ferrofluid seal. The cap is a flat ring and has an elastomeric pad around its outer edge. The pad seats in a recess in the bore of the hub. The cap does not touch the shaft as it rotates with the hub about the shaft. Any excess ferrofluid from the ferrofluid seal is forced radially outward away from the shaft by centrifugal force. The cap contains the excess ferrofluid within the spindle motor and prevents it from entering other areas of the disk drive.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: January 1, 2002
    Assignee: International Business Machines Corporation
    Inventors: M. Amine Hajji, Andrew K. Hanlon, Holavanahally Seshachar Nagaraj
  • Publication number: 20010045702
    Abstract: A hard disk drive spindle motor has a hub, a drive shaft, and a bearing therebetween. The spindle motor also has a ferrofluid seal to prevent any incidental oil emissions from the bearing from entering the drive. A ferrofluid cap is mounted on the axial end of the spindle motor for sealing the ferrofluid seal. The cap is a flat ring and has an elastomeric pad around its outer edge. The pad seats in a recess in the bore of the hub. The cap does not touch the shaft as it rotates with the hub about the shaft. Any excess ferrofluid from the ferrofluid seal is forced radially outward away from the shaft by centrifugal force. The cap contains the excess ferrofluid within the spindle motor and prevents it from entering other areas of the disk drive.
    Type: Application
    Filed: July 17, 2001
    Publication date: November 29, 2001
    Applicant: International Business Machines Corp.
    Inventors: M. Amine Hajji, Andrew K. Hanlon, Holavanahally Seshachar Nagaraj
  • Patent number: 6070881
    Abstract: A configuration seals a leadthrough gap between a wall and a shaft which is passed through the wall and can be set in rotation relative to the wall. The configuration has a sealing ring through which the shaft can be passed as well as a holder that can be firmly connected to the wall and has a cylindrical recess and a groove opening into the recess. The groove has a first groove surface and a second groove surface, between which the sealing ring is held while leaving respective radial gaps as well as a chamber that surrounds the sealing ring and can be filled with oil. The radial gap at the first groove surface is blocked to prevent a throughflow of oil from the chamber. The configuration can be used in a sealing system for an electrical machine filled with hydrogen, in particular for a turbogenerator.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: June 6, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventor: Alexander Longree
  • Patent number: 6029978
    Abstract: A motor is disclosed which includes a shaft and a hub rotating relative to one another and defining a bore therebetween. Also disclosed is a magnetic fluid seal which includes pole pieces supported from the hub, the pole pieces extend toward the shaft. The pole pieces sandwich a non-conducting magnet in a space between the pole pieces. In addition, a contacting process is supported from one of the pole pieces for making electrical contact with the other pole piece to enhance electrical conductivity between the hub and shaft.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: February 29, 2000
    Assignee: Seagate Technology, Inc.
    Inventors: Robert Michael Pelstring, John Charles Dunfield
  • Patent number: 5799951
    Abstract: A rotating sealing device for sealing between a wall separating two mediums under substantially different pressure and a rotatable shaft utilizes a combination of a liquid meatal seal comprising at least one liquid metal ring and a shield means which prevents contamination of the metal ring by gases coming into contact with the liquid metal. Magnetic fluid seal, a ring of an oil material, or inert gas may be used as a shield to protect the liquid metal.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: September 1, 1998
    Assignee: Varian Associates, Inc.
    Inventors: Weston A. Anderson, John E. Richardson