Porous Metal Patents (Class 384/279)
  • Patent number: 6178843
    Abstract: In a rack guide disposed in a casing of a rack and pinion type steering system for slidably supporting a rack bar having rack teeth which engage with a pinion rotatably supported in the casing, the area for bearing the load of the rack bar can be fixed. A slide bearing member 21 has a three-layered structure consisting of a backing metal 22 made of bronze, a sintered alloy layer 23 and a synthetic resin layer 24, the surface of the synthetic resin layer 24 comprising sliding-contact surface portions 25, 26 formed intermittently with the center thereof at the center of curvature “O” of a circular outer peripheral surface of a rack bar 16 and with a radius of curvature equal to the radius of curvature R0 of the same, and the remaining surface portions 27 to 29 formed in other positions than the sliding-contact surface portions 25, 26 so as to be more dented than the sliding-contact surface portions 25, 26.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: January 30, 2001
    Assignee: Daido Metal Company LTD
    Inventors: Katsuhiro Machida, Nobumitsu Mabuchi, Yasuo Ido
  • Patent number: 6174087
    Abstract: A friction bearing, for ceramic shafts, made of metallic hardenable sintered material having an open pore volume of at least 15%, wherein the sintered material is brought into a predetermined shape and is subsequently sintered. A local wear and tear of shaft and bearing is avoided or at least considerably reduced in the region of mixed friction with high lateral forces, it is provided to harden the friction bearing after the sintering.
    Type: Grant
    Filed: November 9, 1999
    Date of Patent: January 16, 2001
    Assignee: Maxon Motor GmbH
    Inventor: Bodo F{umlaut over (u)}tterer
  • Patent number: 6139115
    Abstract: A wheel hub to be used in a golf motor caddie, has an axle; an outer tube, having a first end with a small opening, a second end with a large opening and three sections containing a first, a second and a third chambers, with an inner circular groove cut into the outer tube close to the second end; an inner tube, surrounding the axle; a first, plastics bearing, inserted in the first chamber; a second bearing, inserted in the second chamber; a third, oil-lubricated bearing, inserted in the third chamber; and a C-shaped washer, laid into the groove, for securing the third bearing. The outer tube is a common outer layer for all bearings. The first and second bearings enclose the inner tube, while the third, oil-lubricated bearing directly encloses the axle, such that no uneven distribution of forces and no eccentric rotation occur.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: October 31, 2000
    Inventor: Daniel Chao-Chih Hsieh
  • Patent number: 6119346
    Abstract: A bearing comprising different materials having oil-filled pores in them has a relief space in the middle section which is not provided by machining. The materials are different, have different characteristics, and bear different portions of load the bearing supports, resulting in longer bearing life and reduced noise. Materials 1 and 2 are separately formed and sintered in such a way that material 1 has smaller pores in it and can support higher load, material 2 has larger pores in it and can support lower load, and an end portion of each material is stepped so that material 1 can be partially inserted into material 2 and a relief space is provided on the inner periphery of material 1. The materials 1 and 2 are then joined together into one piece, and the one piece is placed in a sizing die and pressed. The sized one piece is a strong one-piece bearing having an accurate inside diameter and good concentric alignment.
    Type: Grant
    Filed: January 21, 1999
    Date of Patent: September 19, 2000
    Assignees: Hitachi Powdered Metals Co., Ltd, Matsushita Electric Industrial Co., Ltd.
    Inventors: Motohiro Miyasaka, Makoto Kondo, Shigeru Otsuka
  • Patent number: 6120188
    Abstract: An inexpensive bearing unit having a high rotational accuracy and a high reliability is provided for use in information and video-acoustic equipments. In the case of an oil-impregnated sintered bearing (1) in which an inner surface (2) sliding together with a shaft is formed on the bearing body (1) made of a porous sintered alloy, a plurality of concavities (4) are transferred to a tapered portion of the bearing inner surface (2) by forming a part or the whole of the inner surface (2) into a tapered shape or a tapered-like shape at the time of molding a green compact of the sintered alloy and press-fitting a pin (5) formed with protrusions (6) in the subsequent process and moreover, concavities (7) in which the shaft sliding surface is closed are formed by sizing the tapered portion straight at the time of sizing. Because the concavities (7) making a superior dynamic-pressure effect can be formed in a simple process, it is possible to provide an inexpensive bearing unit having a high rotational accuracy.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: September 19, 2000
    Assignee: Matsushita Electric Industiral Co., Ltd.
    Inventors: Hiroyasu Fujinaka, Shigeru Otsuka
  • Patent number: 6086257
    Abstract: A sliding bearing having an improved load-carrying capacity and fatigue strength, by sintering a molded body of iron-based metal mixture powder and concurrently bonding the same to steel-backed metal layer, in which a lubricating oil having the optimal lubrication conditions is impregnated, and providing convenient maintenance and management thereof due to an increased grease non-supplying period, and a manufacturing method of the same. A sliding bearing includes a steel-backed metal layer, and an iron-based sintered alloy layer formed of copper of 10-30 wt % and iron for the residue. The iron-based sintered alloy layer is sintered and concurrently bonded to the steel-backed metal layer. A bush type sliding bearing is formed by inserting a steel-backed metal layer into a mold of a press having cavity for installation of a core at the central portion of the mold and a lower pressing member at the lower portion thereof; filling metal mixture powder formed of copper of 10-30 wt %, graphite of 6.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: July 11, 2000
    Inventor: Woo Chun Lee
  • Patent number: 6082903
    Abstract: A bearing device includes a slidemember made of porous-sintered-metal for slidably supporting a rotational shaft, and a holding member made of the same porous-sintered-metal and holding the slide member. The two members are constructed of the same material, and yet the density of the slide member is greater than that of the holding member so that lubricating oil is supplied continuously from the holding member to the slide member due to the capillary phenomenon. The bearing device constructed as above prevents the lubricating oil from flowing out, improves abrasion-resistance, and thereby extends the service life. Further, this construction allows the bearing device to be smaller and thinner.
    Type: Grant
    Filed: November 2, 1998
    Date of Patent: July 4, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Ryoji Saneshige
  • Patent number: 6024496
    Abstract: An oil sleeve bearing device for holding a shaft of a motor in a motor base and permitting smooth revolving of the shaft therein is disclosed. The oil sleeve bearing device includes a sleeve bearing for holding the shaft, a bearing holder for supporting the sleeve bearing, and a securing member for positioning the sleeve bearing and the shaft in the bearing holder, and there exists a room among the sleeve bearing, the bearing holder, and the securing member for storing oil which can be supplied to the sleeve bearing for lubrication. A buckle structure of the securing member is also disclosed so as to allow the sleeve bearing and the shaft to be easily secured to the bearing holder.
    Type: Grant
    Filed: January 6, 1998
    Date of Patent: February 15, 2000
    Assignee: Delta Electronics, Inc.
    Inventor: Alex Shy
  • Patent number: 6000850
    Abstract: The invention provides a dynamic pressure bearing capable of generating enough dynamic pressure even with the use of a porous material. Dynamic pressure grooves at an inner circumferential surface of a sleeve made of porous material are formed by rolling process. Voids of the porous material at a surface of the dynamic pressure grooves are crushed by this rolling process, making the dynamic pressure grooves airtight. Further, the inner circumferential surface at which the dynamic pressure grooves are formed is subject to a sizing process, by which a bearing surface of the sleeve is crushed so that substantially no voids are present.
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: December 14, 1999
    Assignee: Koyo Seiko Co., Ltd.
    Inventors: Takeshi Takahashi, Masayoshi Onishi
  • Patent number: 5984525
    Abstract: The present invention relates to an oil-retaining bearing for a rotary machine. In the oil-retaining bearing for a rotary machine according to the present invention, a first lock section is provided in a bearing housing; a first thrust spacer is relatively rotatably mounted in the vicinity of the end face of the oil-retaining bearing for a rotary machine; the first thrust spacer is provided with a second lock section, in engagement with the first lock section; a second thrust spacer is relatively non-rotatably mounted on the rotating shaft; and a third thrust spacer having elasticity is relatively rotatably mounted on the rotating shaft; the third thrust spacer being interposed between the first thrust spacer and the second thrust spacer.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: November 16, 1999
    Assignee: Japan Servo Co., Ltd.
    Inventors: Junichi Ikeda, Naoya Ito, Masahiro Mimura, Takeaki Tamabuchi
  • Patent number: 5941646
    Abstract: Two bearing bodies 1 each having a bearing surface 17 are force-fitted into a housing 7 which is opened at one end and closed at the other end thereof, and a shaft 2 (rotary shaft) is inserted in the bearing bodies 1, thereby forming two axially spaced porous oil-impregnated bearings A. The inner peripheral surfaces of the bearing bodies 1 and the oil leak preventing member 11 are formed with a plurality of inclined grooves (hydrodynamic-pressure-generating grooves 5 and air current producing grooves 12). A solid lubricating composition 3 composed of synthetic resin as a base material and oil as a lubricating component by blending lubricating oil or lubricating greases is disposed between the two bearing bodies 1.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: August 24, 1999
    Assignee: NTN Corporation
    Inventors: Natsuhiko Mori, Yasuhiro Yamamoto, Isao Komori, Kazuo Okamura
  • Patent number: 5932946
    Abstract: An improved porous bearing and a motor which is provided with the porous bearing in which the friction losses and reflection of shaft are reduced, noises caused by the vibrations are avoided with low cogging or low jitter, and in addition, the manufacturing process is simplified to obtain long-life products at low cost. The number (C) of grooves of the porous bearing meets at least one of the following equations:nA+mB-C.noteq.0, nA-C.noteq.0 and mB-C.noteq.0wherein A is the number of magnetic poles of the motor magnet, B is the number of the slots of the armature, and n and m are integers, respectively.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: August 3, 1999
    Assignees: Hitachi Powdered Metals Co., Ltd, Matsushita Electric Industrial Co., Ltd.
    Inventors: Motohiro Miyasaka, Makoto Kondo, Shigeru Otsuka
  • Patent number: 5911514
    Abstract: The bearing comprises a metal backing, a sintered layer on said metal backing, and a lining layer infiltrated into pores of the sintered layer and standing proud thereof to provide a bearing surface. The lining layer comprises polytetrafluoroethylene including 2 to 10% by volume of fibrillated aramid fibers.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: June 15, 1999
    Assignee: T&N Technology Limited
    Inventors: Glyndwr John Davies, Philip Moisey, Janette Johnston
  • Patent number: 5899572
    Abstract: A bearing assembly 10 comprising an oil impregnated sintered bushing 15 supported by a bearing retainer 20 and a sintered oil collector 14 disposed in direct physical contact with an external surface of the bushing 15 to remove excess oil from the bushing. The oil collector 14 is preferably substantially oil free or non-impregnated, has a volume at least 10% that of the bushing and has a porosity which is 5 to 10% greater than the porosity of the bushing.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: May 4, 1999
    Assignee: Johnson Electric S.A.
    Inventor: Georg Strobl
  • Patent number: 5895119
    Abstract: A bearing comprising different materials having oil-filled pores in them has a relief space in the middle section which is not provided by machining. The materials are different, have different characteristics, and bear different portions of load the bearing supports, resulting in longer bearing life and reduced noise. Materials 1 and 2 are separately formed and sintered in such a way that material 1 has smaller pores in it and can support higher load, material 2 has larger pores in it and can support lower load, and an end portion of each material is stepped so that material 1 can be partially inserted into material 2 and a relief space is provided on the inner periphery of material 1. The materials 1 and 2 are then joined together into one piece, and the one piece is placed in a sizing die and pressed. The sized one piece is a strong one-piece bearing having an accurate inside diameter and good concentric alignment.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: April 20, 1999
    Assignees: Hitachi Powered Metals Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Motohiro Miyasaka, Makoto Kondo, Shigeru Otsuka
  • Patent number: 5833370
    Abstract: The present invention relates to an oil-retaining bearing for a rotary machine. In the oil-retaining bearing for a rotary machine according to the present invention, a first lock section is provided in a bearing housing; a first thrust spacer is relatively rotatably mounted in the vicinity of the end face of the oil-retaining bearing for a rotary machine; the first thrust spacer is provided with a second lock section, in engagement with the first lock section; a second thrust spacer is relatively non-rotatably mounted on the rotating shaft; and a third thrust spacer having elasticity is relatively rotatably mounted on the rotating shaft; the third thrust spacer being interposed between the first thrust spacer and the second thrust spacer.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: November 10, 1998
    Assignee: Japan Servo Co., Ltd.
    Inventors: Junichi Ikeda, Naoya Ito, Masahiro Mimura, Takeaki Tamabuchi
  • Patent number: 5810481
    Abstract: Oil retaining bearing members 2a and 2b for supporting a rotative shaft 1 are arranged in a bearing housing 7 with an interval. The bearing housing 7 has a bottom portion, one end being opened and another end being closed. A porous spacer 3 for supplying a lubrication oil is closely inserted between the oil retaining bearings 2a and 2b. An oil thrower 8 is arranged at an upper portion of the bearing housing 7 and a thrust bearing 5 is arranged at a lower portion. The open end of the bearing housing 7 is arranged on the upper portion and the another end of the bearing housing 7 is arranged on the lower portion of the bearing housing 7, and state a lubrication oil 4a is enclosed in the housing to immerse a part of the porous spacer 3 to some degree. The pore diameter of the porous spacer 3 is larger than that of the oil retaining bearings 2a and 2b. By utilizing capillary tube action in by the porous spacer 3, the lubrication oil 4a is supplied to the oil retaining bearing 2a.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: September 22, 1998
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Co., Ltd.
    Inventors: Katsutoshi Nii, Makoto Kondoh, Takashi Kono, Yoshihiro Sato, Seiichiro Terashima
  • Patent number: 5786648
    Abstract: A motor comprises a rotary shaft, an oil impregnated sintered bearing rotatably supporting the rotary shaft, a bearing holder supporting the oil impregnated sintered bearing and a motor case. A lateral pressure device is provided to the rotary shaft which abrasively contacts the rotary shaft from a radial direction and provides a lateral pressure so that the rotary shaft is displaced in the radial direction. The lateral pressure device further comprises an inner ring made of an oil impregnated sintered member in which a through-hole abrasively contacts the rotary shaft from the radial direction is formed, an elastic member which provides a lateral pressure so that the rotary shaft is displaced in the radial direction and an outer ring which holds the elastic member and is fixed to the motor case.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: July 28, 1998
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Takashi Iwanami
  • Patent number: 5785429
    Abstract: A sintered oilless kinetic pressure bearing containing an oil is formed with a plurality of grooves along the inner diameter to produce the kinetic pressure, in which the proportion between the groove and corresponding inner periphery portion is appropriately maintained according to the Reynolds equation for decreasing initial abrasion and heightening durability to lengthen the life while a pressure is induced throughout the inner periphery for providing a stiffness coefficient impervious to a great impact or high load imposed by an external force and heightening stability in the rotating motion. The bearing in a cylindrical sintered oilless bearing includes a plurality of grooves along the inner periphery plane thereof in the lengthwise direction of a shaft such that an interval between the grooves become respective inner periphery portions and the groove and inner periphery portion are partitioned by side planes. Thus, assuming that an angle range of the groove is denoted by .alpha.
    Type: Grant
    Filed: April 9, 1997
    Date of Patent: July 28, 1998
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventor: Dae Hyun Jeong
  • Patent number: 5765358
    Abstract: An aerostatic axial bearing (6) of an open-end spinning machine in which the bearing plate (601) of the axial bearing (6) is made of a permeable material, has a bearing plate (601) provided with one or several air channels (605), the task of which is to convey the air closer to the bearing gap (630) before it goes through the permeable bearing plate material. Thereby, the utilization of an additional choke can be avoided. Furthermore the mechanical properties of the holder bearing plate (601) are improved.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: June 16, 1998
    Assignee: Rieter Ingolstadt Spinnereimaschinenbau AG
    Inventors: Erich Bock, Manfred Knabel, Edmund Schuller
  • Patent number: 5762423
    Abstract: A bearing device wherein a porous body is formed with a bearing surface (5a) which comes in slide contact with the slide surface of a shaft (3) to be supported, while a porous oil-impregnated bearing (5) impregnated with a lubricating oil or lubricating grease and a solid resin lubricating composition (7) in the form of a synthetic resin substrate having a lubricating component dispersed and held therein are disposed in contact with each other.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: June 9, 1998
    Assignee: NTN Corporation
    Inventors: Natsuhiko Mori, Yasuyuki Watanabe, Yasuhiro Yamamoto
  • Patent number: 5746516
    Abstract: An improved porous bearing and a motor which is provided with the porous bearing in which the friction losses and reflection of shaft are reduced, noises caused by the vibrations are avoided with low cogging or low jitter, and in addition, the manufacturing process is simplified to obtain long-life products at low cost. The number (C) of grooves of the porous bearing meets at least one of the following equations:nA+mB-C.noteq.0, nA-C.noteq.0 and mB-C.noteq.0wherein A is the number of magnetic poles of the motor magnet, B is the number of the slots of the armature, and n and m are integers, respectively.
    Type: Grant
    Filed: August 8, 1996
    Date of Patent: May 5, 1998
    Assignees: Hitachi Powdered Metals Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Motohiro Miyasaka, Makoto Kondo, Shigeru Otsuka
  • Patent number: 5704718
    Abstract: Oil-impregnated sintered bearing has a bearing bore with axially extending grooves formed therein so that in a cross-section of the bearing bore concave and convex portions alternate in the circumferential direction, the surface porosity of the convex portions being preferably larger than that of the concave portions. Formed in part of an inner circumference of the bearing bore, is a bearing surface for supporting a rotary shaft, the rest of the inner circumference other than the bearing surface extending toward an end edge of the bearing bore at a taper angle of 2.degree. to 10 over a width of at least 1/3 or more of an axial width of the bearing surface.
    Type: Grant
    Filed: July 12, 1996
    Date of Patent: January 6, 1998
    Assignee: NTN Corporation
    Inventors: Natsuhiko Mori, Yoshinori Ito, Toshihiko Tanaka, Yasuhiro Yamamoto
  • Patent number: 5645355
    Abstract: A bearing unit in which two oil sintered slide bearings are fitted in a bearing space of non-magnetic bearing housings to be spaced away from each other and a magnetic fluid is interposed between a rotary shaft and the oil sintered slide bearings to rotatably support the rotary shaft. The rotary shaft is made from a material having permeability, and a ring-shaped permanent magnet is fixedly provided between the two oil sintered slide bearings to be spaced therefrom. The magnetic fluid is held between the two oil sintered slide bearings to be circulated.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: July 8, 1997
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Co., Ltd.
    Inventors: Hidekazu Tokushima, Motohiro Miyasaka, Michihiro Aizawa, Hideo Shikata, Katsutoshi Nii
  • Patent number: 5524502
    Abstract: A base board supported on an X-Y stage or the like of an exposure apparatus includes a cylindrical fixed member. Porous pads held on the fixed member support the inner circumferential surface of a guide member provided as one body with a holding member for holding a wafer in a non-contact state. The base board is rotated around its central axis by a .theta. linear motor, and is reciprocated in the vertical direction by Z linear motors provided at an equal interval in the circumferential direction. Each of the Z linear motors and the .theta. linear motor includes a rotor fixed to the holding board, and a stator that includes a coil fixed to the base board.
    Type: Grant
    Filed: March 2, 1994
    Date of Patent: June 11, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventor: Eiji Osanai
  • Patent number: 5501529
    Abstract: A bearing insert for being cast into an aluminum alloy engine block is made by a ferrous powder metal sintering process to make a skeleton structure which is permeable to the molten aluminum alloy in the block casting process. The insert is made of a material having a similar composition as the bearing cap so as to equalize machining and thermal expansion properties of the cap and block so as to provide improved roundness of the bearing in the machining operations for forming the bearing support and in operation of the engine.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: March 26, 1996
    Assignee: Zenith Sintered Products, Inc.
    Inventors: Terry M. Cadle, Carl J. Landgraf, Georgia M. Mayer
  • Patent number: 5490730
    Abstract: The improved slide bearing assembly comprises at least a shaft and a bush that is formed of a porous iron-base sintered material and is characterized in that the bush is impregnated with a lubricant oil having a viscosity of 240-1500 cSt. The bearing assembly can be operated in slow- and high-pressure applications without oil refillings for a prolonged period of at least several years. The shaft is preferably formed of an iron or a steel member that have been subjected to a treatment of surface modification. The slide bearing assembly is preferably used in such an environment that the working pressure applied to the sliding surfaces is at least 6.0 kgf/mm.sup.2 and that the sliding speed is in the range 2-5 cm/sec.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: February 13, 1996
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hideki Akita, Makoto Ota, Hideaki Nakatani, Kazuyoshi Hatano, Manabu Ogasawara
  • Patent number: 5474386
    Abstract: A bearing system comprises a motor shaft, bearings that support the shaft in a rotatable manner, a cylindrical bearing holder that holds the bearings and a cylindrical sleeve on the inner periphery of the bearing holder. The cylindrical sleeve is either made of metal of a material of high rigidity. The cylindrical sleeve, furthermore, is either integrally formed or press-fitted on the periphery of the bearing holder.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: December 12, 1995
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Izumi Komatsu
  • Patent number: 5441386
    Abstract: A lubricating system for cooling fans is provided and mainly consists of a self-lubricating bearing, an oil retaining cap, and an oil retaining ring. The oil retaining ring has a central hole, an inner portion adjacent to the central hole and having a round cross section, and an outer flange portion integrally extended from the inner portion and having a concavo-concave cross section. The oil retaining cap is bowl-shaped and has a central opening, an inner convex portion, and an outer concave portion. The self-lubricating bearing has two end surfaces each of them being provided with a plurality of shallow bevel grooves inclining toward an axially extended shaft hole of the bearing, and an annular recess formed at a middle section of the shaft hole.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: August 15, 1995
    Inventor: Hsin M. Hsieh
  • Patent number: 5433532
    Abstract: An annular bearing has its bearing surface on the inner surface. The bearing surface is formed to improve bearing properties, that is, to improve adaptability to an impact load and an imbalanced load. A method of manufacturing a bearing having such a bearing surface is given. An annular bearing blank, together with a mandrel having a plurality of arch-shaped ridges extending axially on the outer surface of the mandrel and a sleeve fitted on a periphery of the mandrel, is pushed into an inner hole of a molding die. The material is accordingly closed in a space defined by the mandrel, the inner hole, the sleeve and an ejector inserted into the bottom part of the inner hole. Thus, a plurality of arch-shaped recesses are formed extending axially on the inner surface of the bearing blank.
    Type: Grant
    Filed: August 15, 1994
    Date of Patent: July 18, 1995
    Assignee: Daido Metal Company, Ltd.
    Inventors: Hideharu Kawageo, Takayuki Shibayama, Yoshitaka Kondo, Motoji Komori
  • Patent number: 5397184
    Abstract: A hydrostatic gas bearing comprises a pair of bearing structural members 4 which make up an inner ring 3 and each have a frusto-conical engaging face 5 formed on the radially outer peripheral surface thereof, a pair of bearing members 2 which are fixed to the respective bearing structural members 4, and each formed with a radially inner engaging face 6 for engagement with the taper of the engaging face 5, and an outer bearing surface 10 which is aligned parallel to the inner engaging face 6, wherein since each bearing member 2 is pressed in an axial direction by an attachment member 7 and thereby fastened with a uniform pressing force to the bearing structural member 4, positional displacement of the bearing member 2 relative to the bearing structural member 4 and uneven deformation of the bearing member 2 can be suppressed so that bearing characteristics can be maintained in a simple structure.
    Type: Grant
    Filed: April 12, 1994
    Date of Patent: March 14, 1995
    Assignee: NSK, Ltd.
    Inventor: Takashi Murai
  • Patent number: 5372433
    Abstract: An object of this invention is to provide a bearing device for an electric motor in which a bearing holder holding an oil-impregnated bearing provides good area contact from the beginning and can be readily formed with high productivity.
    Type: Grant
    Filed: February 24, 1994
    Date of Patent: December 13, 1994
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Toru Nakanishi, Hisaya Nakagawa
  • Patent number: 5307902
    Abstract: In a meter counter assembly of a gas meter, a rotatable shaft of a gear train is journaled in a bore that extends through a support plate mounted in the housing of the counter. The plate is of a porus material, forming capillary passages for the transmission of lubricant therethroughout. A portion of the support plate extends into a lubricant reservoir in the housing. In use, lubricant migrates through the capillary passages to the bore from the reservoir for lubrication of the shaft.
    Type: Grant
    Filed: March 24, 1993
    Date of Patent: May 3, 1994
    Assignee: Dresser Industries, Inc.
    Inventors: Richard T. Herrmann, Albert B. Atkinson
  • Patent number: 5295330
    Abstract: A centrifugal disk finisher includes a porous layer at the bottom of the vertical wall of the containment vessel. A pressurized fluid, preferably air, is forced through the porous layer so as to form a fluid bearing between the bottom of the porous layer and the spinning disk enclosed within the containment vessel. The containment vessel is levitated above the spinning disk by a small amount due to the presence of the fluid bearing, so that the disk spins without any contact with the containment vessel, thus reducing wear. The fluid bearing also acts as a seal, which repels particles from the interface between the disk and the porous layer due to the small height of the fluid bearing and its imperviousness to all but the most energetic particles.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: March 22, 1994
    Inventor: Steve E. Hoffman
  • Patent number: 5282688
    Abstract: In a sintered oil impregnated bearing constructed of a bearing main body made of a porous type sintered alloy on which is formed a bearing hole for inserting a rotating shaft therethrough, the pores on the axially lying sliding face of the inner peripheral surface of the bearing hole on which the rotating shaft slides are crushed. The sintered oil impregnated bearing is manufactured, at the time of forming powder compact, by forming a through hole defining the bearing hole, by a rod having a roughening section formed thereon, thereby crushing the pores which are in contact with the roughening section, and afterward by sintering the powder compact. Because the pores on the sliding face are crushed, the lubricating oil on the sliding face does not leak, thereby forming a strong oil film having no oil pressure drop on the sliding face, and thus preventing the local contact between the rotating shaft and the sliding face. It is therefor is possible to lower the coefficient of friction of the bearing.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: February 1, 1994
    Assignees: Mitsubishi Materials Corporation, Asmo Co., Ltd.
    Inventors: Noboru Kanezaki, Takeshi Tanaka, Yoshiaki Hayashi
  • Patent number: 5281035
    Abstract: An improvement in the leak proof construction and the rotating shaft attachment means for an oil-containing bearing includes a plurality of oil-storing grooves formed on the oil-containing bearing such that the lubricant oil required by the rotation of the rotating shaft can be received and contained therein. On an outlet portion of the rotating shaft and the oil-containing bearing, there is provided an oil guiding plate which rotates with the rotating shaft. The lubricant oil escaping along the rotating shaft will be expelled by the oil guiding plate into the oil-storing grooves of the oil containing bearing by the centrifugal force generated by the rotation of the oil guiding plate.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: January 25, 1994
    Assignee: Delta Electronics, Inc.
    Inventor: Jansen Lo
  • Patent number: 5145266
    Abstract: In a bearing apparatus having an oilless bearing, plural grooves are formed on an outer surface of the bearing or an inner surface of a bearing holder for holding lubricant oil which is overflowed from the bearing, thereby the lubricant is maintained in a long service.
    Type: Grant
    Filed: July 16, 1991
    Date of Patent: September 8, 1992
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ryoji Saneshige, Shigeru Ootsuka
  • Patent number: 5129738
    Abstract: Bearing devices which rotatably support a shaft in a bearing having a plurality of radial projections formed on either the inside peripheral surface of the bearing or the peripheral surface of the shaft are discolsed. The bearing has an oil film formed between the projections and the mating part opposite to the projections for supporting the shaft. The projections are adapted to face the mating part with a specified area sufficient to cause a specified oil film dynamic pressure effect to occur. In one form of the invention, the projections are formed of an oil impregnated sintered metal, the part of the surface of the projections facing the mating part having been subject to a filling-up process.
    Type: Grant
    Filed: January 24, 1991
    Date of Patent: July 14, 1992
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Hisaya Nakagawa
  • Patent number: 5120091
    Abstract: An oil impregnated sintered bearing suitably used for a spindle motor, which rotatably supports a shaft in a longitudinal opening of the bearing for supporting the motor shaft. The longitudinal opening is formed by at least three inwardly projecting surfaces defining a portion of the longitudinal opening and being arranged symmetrically with respect to a central longitudinal axis of the opening. The surfaces are almost tangential to a motor shaft disposed in the opening such that the surfaces have a clearance relative to the shaft which is smaller than that of other inner peripheral portions defining the opening. A wedge-like clearance is formed between the shaft and a side of the projecting surfaces toward which the shaft rotates.
    Type: Grant
    Filed: September 18, 1990
    Date of Patent: June 9, 1992
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Hisaya Nakagawa
  • Patent number: 5120140
    Abstract: A sintered oil-impregnated bearing is disclosed having a plurality of evenly extending smoothed areas on the inner periphery surface for receiving a rotary shaft, the smoothed areas having a constant angular width of 10.degree. to 90.degree., the remaining surface areas between any adjoining two of said smoothed areas being kept porous. Such a sintered oil-impregnated bearing can be realized without the process of aging and ensures a good oil circulation on the smoothed surface areas, a high precision assembling operation because of the exactly circular and concentric configuration of the inner and outer peripheries and an easy and accurate alignment of the smoothed surface areas and the corresponding contact areas of the rotary shaft. Therefore, a sintered oil-impregnated bearing according to the invention is free from any metallurgical damage and can be manufactured in an existing manufacturing facility without significantly modifying the manufacturing equipment.
    Type: Grant
    Filed: October 23, 1990
    Date of Patent: June 9, 1992
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventors: Hisaya Nakagawa, Toru Nakanishi
  • Patent number: 5098206
    Abstract: A shaft bearing assembly, particularly for a miniature electric motor. In the case of the present shaft bearing assembly, an oil-impregnated dampening disc made of an absorbent material the capillary action of which is greater than that of the porous bearing block is disposed between the thrust collar of the shaft and the axial end face of the bearing block. The shaft bearing assembly is particularly suitable for electric motors of smaller size and is effective in reducing motor noise.
    Type: Grant
    Filed: February 22, 1991
    Date of Patent: March 24, 1992
    Assignee: Interelectric AG
    Inventor: Bodo Futterer
  • Patent number: 5094548
    Abstract: A composite and self-lubricating bushing comprises a monolithic steel body having a machined internal cylindrical surface and a porous bearing layer applied to the surface. The porous bearing layer is formed by compacting and sintering a particulate bearing material. The steel body may also include a cavity for storing lubricant and at least one passageway extending between the cavity and the internal cylindrical surface. The bushing may be fabricated by positioning the steel body concentrically over an elastomeric plug, charging the annular cavity between the body and the plug with a sinterable particulate, expanding the elastomeric plug diametrically to compact the particulate, removing the plug and heating the bearing body and compacted particulate.
    Type: Grant
    Filed: July 16, 1990
    Date of Patent: March 10, 1992
    Assignee: Danly Corporation
    Inventor: James C. Danly, Sr.
  • Patent number: 5028148
    Abstract: A slide bearing device having an oil-containing sintered member and a fixed pad fixed to the sintered member and supporting a sliding member through a film of a lubricating oil supplied from the sintered member, wherein a dynamic pressure of the lubricating oil is generated so as to forcibly form and maintain the oil film between the fixed pad and the sliding member.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: July 2, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Hisanobu Kanamaru, Katsuyoshi Terakado, Shin Onose
  • Patent number: 4878768
    Abstract: Disclosed is a bearing having an improved corrosion resistance, which comprises: a base metal; and, a bearing layer of Cu-series alloy having a skeleton structure of Cu alloy. The clearance of the skeleton structure are filled essentially with Pb-containing phase. The deterioration of corrosion resistance due to dissolution of Pb in the clearances into degraded engine oil is prevented by including into the Pb-containing phase In at a depth exceeding approximately 20 .mu.m mearued from the surface of the bearing layer.
    Type: Grant
    Filed: August 4, 1988
    Date of Patent: November 7, 1989
    Assignee: Taiho Kogyo, Ltd.
    Inventors: Tatsuhiko Fukuoka, Takashi Suzuki
  • Patent number: 4865467
    Abstract: A roll-formed bushing for sliding surface bearings has no machining allowance in the bearing bore and is made of a strip section and has a butt joint that extends throughout the width of the bearing. In order to reduce the allowances of the bore diameter and the outside diameter of the bearing bushing, the butt joint has been closed by charge carrier beam welding.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: September 12, 1989
    Assignee: Kolbenschmidt Aktiengesellschaft
    Inventors: Karl Becker, Alfred Berger, Joachim Iwansky, Roland Koble, Karl Back
  • Patent number: 4853180
    Abstract: A die assembly having a cavity in which powdered metal is compressed with upper and lower punches. A core extends through the lower punch to form the inner wall of a bushing, and a core extension rod having a lateral protrusion that extends into the cavity to form a groove in the upper portion of the bushing. The core and the core extension rod move in concert between positions to receive powder, compress it and moves upward to afford expelling the finishing bushing. One stationary protrusion extends from the die into the cavity to form a groove in the powdered metal along the full length of the completed bushing. Air passage means are used to direct air into the cavity to remove residue powder that may eventually build-up and cause inaccuracies. Also, in the preferred embodiment a powder feeder means is used on a die table to reciprocate between a retracted, inactive position and an extended position to deposit powdered metal into the cavity and later to bump a finished bushing across the table.
    Type: Grant
    Filed: September 15, 1988
    Date of Patent: August 1, 1989
    Assignee: Martin Sprocket & Gear, Inc.
    Inventor: Billy G. Howard
  • Patent number: 4848932
    Abstract: A gas-static and gas-dynamic radial bearing assembly includes a shaft having a supply line extending in the interior thereof for bearing gas. The shaft has a portion in the form of a porous sintered body. A bearing has a given bearing length, part of which is occupied by the porous sintered body. The bearing has a bearing box divided into individual segments partly overlapping one another at given regions. Spring elements in the vicinity of said given regions spread said segments apart.
    Type: Grant
    Filed: August 3, 1988
    Date of Patent: July 18, 1989
    Assignee: Interatom GmbH
    Inventor: Heinrich Puetz
  • Patent number: 4838710
    Abstract: A static pressure gas bearing assemby having a gaseous fluid discharging bearing member for supporting a shaft by the discharged gaseous fluid is disclosed. The bearing member is made of porous graphite. For the manufacture, carbon particles approximately 80% of which have particle diameters not greater than approx. 40 microns, more particularly, particle diameters ranging from 1-20 microns are used. The carbon particles are subjected to molding, calcination and graphitization, whereby a porous graphite member having pores distributed substantially uniformly is obtained. In another aspect of the invention, the bearing member is made of a porous graphite material having a specific degree of swelling. Also, in another aspect, the surface of the shaft to be supported by the bearing member is coated with titanium nitride by ion plating treatment. In this manner, a high-precision and high-prerformance bearing assembly can be provided with reduced manufacturing costs.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: June 13, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Jiro Ohta, Sadamu Tozawa, Koichi Matsushita, Yutaka Maruyama
  • Patent number: 4820140
    Abstract: The invention comprises a rotary pump with sliding vanes with a self-lubricating solid coating covering the exterior end facing surfaces of the rotor and end facing surfaces of air transfer end plates. Additionally disclosed herein is a rotary pump with sliding vanes with a pair of bushings centrally located in the rotor with the internal bearing facing surfaces of the bushings covered with a self-lubricating solid coating.
    Type: Grant
    Filed: October 26, 1987
    Date of Patent: April 11, 1989
    Assignee: Sigma-Tek, Inc.
    Inventor: Jerry B. Bishop
  • Patent number: RE36405
    Abstract: The improved slide bearing assembly comprises at least a shaft and a bush that is formed of a porous iron-base sintered material and is characterized in that the bush is impregnated with a lubricant oil having a viscosity of 240-1500 cSt. The bearing assembly can be operated in slow- and high-pressure applications without oil refillings for a prolonged period of at least several years. The shaft is preferably formed of an iron or a steel member that have been subjected to a treatment of surface modification. The slide bearing assembly is preferably used in such an environment that the working pressure applied to the sliding surfaces is at least 6.0 kgf/mm.sup.2 and that the sliding speed is in the range 2-5 cm/sec.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: November 23, 1999
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Hideki Akita, Makoto Ota, Hideaki Nakatani, Kazuyoshi Hatano, Manabu Ogasawara