Patents by Inventor Mutsumi Muraoka

Mutsumi Muraoka has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10415665
    Abstract: A fluid-filled vibration-damping device including first and second mounting members elastically connected by a main rubber elastic body and a fluid chamber whose wall is partially constituted by the main rubber elastic body. A sealing member attached to the second mounting member has a step part, and an attaching tube part and a sealing tube part on opposite sides of the step part. A press-fit projection is formed peripherally partially on at least one of an inner peripheral face of the attaching tube part and an outer peripheral face of the second mounting member, so as to secure press-fit the second mounting member inserted into the attaching tube part. A transmission prevention part is provided in the step part on a portion that transmits press-fit stress from the attaching tube part to the sealing tube part so as to reduce stress transmission.
    Type: Grant
    Filed: April 22, 2016
    Date of Patent: September 17, 2019
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Atsushi Goto, Tetsuji Ando, Mutsumi Muraoka
  • Publication number: 20190048956
    Abstract: An outer member fixed to an outer peripheral portion of a main rubber elastic body has a projecting part projecting peripherally outward. First and second assembly members each include an annular fastening plate part so that the annular fastening plate parts are superposed and fixed while clamping the projecting part to constitute a bracket supporting the projecting part. A clinch fastening part is formed such that one of the annular fastening plate parts is folded back to cover an outer peripheral rim of the other annular fastening plate part and fastened by clinching to the other annular fastening plate part with clinching force being not directly exerted on the projecting part. A locking section is provided at the annular fastening plate part of at least one of the assembly members, and the projecting part being locked and positioned relative to the annular fastening plate part.
    Type: Application
    Filed: August 8, 2017
    Publication date: February 14, 2019
    Applicant: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Hiroyuki KASHIHARA, Hirotaka MATSUI, Mutsumi MURAOKA
  • Publication number: 20190032740
    Abstract: A vibration damping device including first and second side opposition surfaces mutually and separately opposed and elastically connected by a main rubber elastic body. A protruding part is provided at the first side opposition surface to protrude toward the second side opposition surface with a protrusion dimension with which the protruding part does not reach the second side opposition surface, in a section peripherally inside an outer peripheral edge of the main rubber elastic body. A recessed part is provided at the second side opposition surface in opposition to the protruding part so as to be recessed to a distant side from the protruding part and open in the second side opposition surface. The protruding part has an outer face without a break and is buried in the main rubber elastic body. The recessed part is filled with the main rubber elastic body.
    Type: Application
    Filed: July 26, 2017
    Publication date: January 31, 2019
    Applicant: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Hiroyuki KASHIHARA, Hirotaka MATSUI, Mutsumi MURAOKA
  • Patent number: 9651111
    Abstract: A fluid-filled vibration damping device including a vibration damping device main unit which has a main rubber elastic body elastically connecting first and second mounting members, and a fluid chamber whose wall is partially constituted by the main rubber elastic body. The vibration damping device main unit further includes a temporary joint member locked on the second mounting member and temporarily coupled thereto in an axial direction, and an annular sealing part provided to the temporary joint member and overlapped on the second mounting member in the axial direction with a sealing rubber sandwiched therebetween for achieving a temporary seal. A sealing coupling member is mounted on the second mounting member while exerting a pressing force in a direction of overlapping on the second mounting member and the temporary joint member for increasing a compression ratio of the sealing rubber and achieving a full seal.
    Type: Grant
    Filed: May 21, 2015
    Date of Patent: May 16, 2017
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Mutsumi Muraoka, Tomomi Suzuki, Kei Okumura, Wakako Michiyama
  • Publication number: 20160238102
    Abstract: A fluid-filled vibration-damping device including first and second mounting members elastically connected by a main rubber elastic body and a fluid chamber whose wall is partially constituted by the main rubber elastic body. A sealing member attached to the second mounting member has a step part, and an attaching tube part and a sealing tube part on opposite sides of the step part. A press-fit projection is formed peripherally partially on at least one of an inner peripheral face of the attaching tube part and an outer peripheral face of the second mounting member, so as to secure press-fit the second mounting member inserted into the attaching tube part. A transmission prevention part is provided in the step part on a portion that transmits press-fit stress from the attaching tube part to the sealing tube part so as to reduce stress transmission.
    Type: Application
    Filed: April 22, 2016
    Publication date: August 18, 2016
    Applicant: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Atsushi GOTO, Tetsuji ANDO, Mutsumi MURAOKA
  • Patent number: 9243680
    Abstract: A fluid-filled type active vibration damping device including: a pressure-receiving chamber; an equilibrium chamber; an orifice passage permitting fluid flow between the two chambers; an oscillation member oscillated by an electromagnetic actuator; an intermediate chamber; and a pressure transmission passage through which pressure fluctuations produced in the intermediate chamber is applied to the pressure-receiving chamber. The intermediate chamber is provided independently of the equilibrium chamber. The pressure transmission passage comprises a filter orifice tuned to higher frequency than the orifice passage. A movable plate is provided for limiting an amount of fluid flow through the filter orifice. A leak hole is formed for continuously interconnecting the intermediate chamber and the pressure-receiving chamber, and a liquid column resonance frequency of the leak hole is set to not more than half of that of the filter orifice.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: January 26, 2016
    Assignee: SUMITOMO RIKO COMPANY LIMITED
    Inventors: Hironori Koyama, Mutsumi Muraoka
  • Publication number: 20150252866
    Abstract: A fluid-filled vibration damping device including a vibration damping device main unit which has a main rubber elastic body elastically connecting first and second mounting members, and a fluid chamber whose wall is partially constituted by the main rubber elastic body. The vibration damping device main unit further includes a temporary joint member locked on the second mounting member and temporarily coupled thereto in an axial direction, and an annular sealing part provided to the temporary joint member and overlapped on the second mounting member in the axial direction with a sealing rubber sandwiched therebetween for achieving a temporary seal. A sealing coupling member is mounted on the second mounting member while exerting a pressing force in a direction of overlapping on the second mounting member and the temporary joint member for increasing a compression ratio of the sealing rubber and achieving a full seal.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 10, 2015
    Inventors: Mutsumi MURAOKA, Tomomi SUZUKI, Kei OKUMURA, Wakako MICHIYAMA
  • Patent number: 8936235
    Abstract: A fluid-filled type vibration damping device including a base component and a tubular mating component. The tubular mating component is externally fitted onto the base component by means of a diameter-constricting caulking with a sealing rubber clasped therebetween so as to constitute a mate-fastened portion. The tubular mating component extends axially outward beyond a sealed section of the mate-fastened portion so as to provide a caulking tube portion. A diametrical position of the tubular mating component at the sealed section is determined by contact of the caulking tube portion against an outside peripheral face of a positioning projection provided on the base component so as to define a diametrical positioning portion. The caulking tube portion is constricted in diameter and held in engagement with an axial edge portion of the positioning projection so as to form an axial positioning portion.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: January 20, 2015
    Assignees: Sumitomo Riko Company Limited, Nissan Motor Co., Ltd.
    Inventors: Hironori Koyama, Mutsumi Muraoka, Hironori Daito, Satoshi Umemura, Jyoji Tsutsumida, Shinichi Suganuma, Takeshi Hamanaka, Kaoru Murakami
  • Patent number: 8919748
    Abstract: An active antivibration device which includes a main body, a mobile element which is elastically supported inside the main body and movable in an axial direction of the main body, and a coil which is disposed inside the main body and fixed to the main body. The mobile element includes a mobile axis body supported in the axial direction of the main body, and a first yoke, a permanent magnet and a second yoke which are held by the mobile axis body and disposed successively along an axial direction of the mobile axis body. The permanent magnet is magnetized in the axial direction of the mobile axis body and disposed between the first yoke and the second yoke.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: December 30, 2014
    Assignees: Keihin Corporation, Sumitomo Riko Company Limited
    Inventors: Atsushi Urayama, Hirozumi Kon, Hironori Koyama, Mutsumi Muraoka, Atsushi Muramatsu
  • Patent number: 8807546
    Abstract: A fluid filled vibration damping device including: a first mounting member; a second mounting member having a cylindrical portion; and a main rubber elastic body elastically connecting the first and second mounting members. The first mounting member is fixed to one end of the main rubber elastic body, and an insertion metal fitting in a cylindrical shape is fixed onto an outer peripheral face of another end thereof, and the cylindrical portion of the second mounting member is bonded by pressure to the insertion metal fitting with a sealing rubber in between in a fluid-tight manner. The insertion metal fitting is provided with an inward protrusion where part of a wall portion protrudes inward. A sealing rubber storage space is formed between the inward protrusion and the cylindrical portion of the second mounting member.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: August 19, 2014
    Assignee: Tokai Rubber Industries, Ltd.
    Inventors: Hironori Daito, Mutsumi Muraoka, Hironori Koyama
  • Patent number: 8789819
    Abstract: A fluid-filled type active vibration damping device including: a first mounting member; a second mounting member; a main rubber elastic body connecting the first and second mounting members; a fluid chamber; an oscillation member that partially defines a wall of the fluid chamber; an actuator having an output shaft, the output shaft being connected to the oscillation member; a connecting member that interconnects the oscillation member and the output shaft at one point with the oscillation member superposed against a projecting distal end of the output shaft; and an abutting portion provided by superposed faces of the oscillation member and the output shaft being positioned in abutment with each other at an outer peripheral side of a connected section where the oscillation member and the output shaft are interconnected by the connecting member.
    Type: Grant
    Filed: March 8, 2012
    Date of Patent: July 29, 2014
    Assignee: Tokai Rubber Industries, Ltd.
    Inventors: Mutsumi Muraoka, Satoshi Umemura, Hironori Koyama
  • Publication number: 20130264756
    Abstract: A fluid filled vibration damping device including: a first mounting member; a second mounting member having a cylindrical portion; and a main rubber elastic body elastically connecting the first and second mounting members. The first mounting member is fixed to one end of the main rubber elastic body, and an insertion metal fitting in a cylindrical shape is fixed onto an outer peripheral face of another end thereof, and the cylindrical portion of the second mounting member is bonded by pressure to the insertion metal fitting with a sealing rubber in between in a fluid-tight manner. The insertion metal fitting is provided with an inward protrusion where part of a wall portion protrudes inward. A sealing rubber storage space is formed between the inward protrusion and the cylindrical portion of the second mounting member.
    Type: Application
    Filed: March 7, 2013
    Publication date: October 10, 2013
    Applicant: TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Hironori DAITO, Mutsumi MURAOKA, Hironori KOYAMA
  • Patent number: 8292273
    Abstract: A fluid filled type vibration damping device having a pressure-receiving chamber and an equilibrium chamber disposed on either side of a partition member. A movable cover member juxtaposed against the partition member from the pressure receiving chamber side to cover a communicating hole of the partition member. An outside peripheral edge of the movable cover member is held in intimate contact against the partition member through urging force of an elastic retainer portion. Pressure of both chambers will acts on both faces of a movable rubber film, thereby constituting a pressure fluctuation absorbing mechanism. The outside peripheral edge of the movable cover member is separated from the partition member in opposition to the urging force by negative pressure in the pressure receiving chamber for providing a shunting mechanism for preventing excessive negative pressure in the pressure receiving chamber.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: October 23, 2012
    Assignee: Tokai Rubber Insustries, Ltd.
    Inventors: Mutsumi Muraoka, Satoshi Umemura
  • Publication number: 20120242021
    Abstract: A fluid-filled type vibration damping device including a base component and a tubular mating component. The tubular mating component is externally fitted onto the base component by means of a diameter-constricting caulking with a sealing rubber clasped therebetween so as to constitute a mate-fastened portion. The tubular mating component extends axially outward beyond a sealed section of the mate-fastened portion so as to provide a caulking tube portion. A diametrical position of the tubular mating component at the sealed section is determined by contact of the caulking tube portion against an outside peripheral face of a positioning projection provided on the base component so as to define a diametrical positioning portion. The caulking tube portion is constricted in diameter and held in engagement with an axial edge portion of the positioning projection so as to form an axial positioning portion.
    Type: Application
    Filed: March 8, 2012
    Publication date: September 27, 2012
    Applicants: NISSAN MOTOR CO., LTD., TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Hironori KOYAMA, Mutsumi MURAOKA, Hironori DAITO, Satoshi UMEMURA, Jyoji TSUTSUMIDA, Shinichi SUGANUMA, Takeshi HAMANAKA, Kaoru MURAKAMI
  • Publication number: 20120242020
    Abstract: A fluid-filled type active vibration damping device including: a first mounting member; a second mounting member; a main rubber elastic body connecting the first and second mounting members; a fluid chamber; an oscillation member that partially defines a wall of the fluid chamber; an actuator having an output shaft, the output shaft being connected to the oscillation member; a connecting member that interconnects the oscillation member and the output shaft at one point with the oscillation member superposed against a projecting distal end of the output shaft; and an abutting portion provided by superposed faces of the oscillation member and the output shaft being positioned in abutment with each other at an outer peripheral side of a connected section where the oscillation member and the output shaft are interconnected by the connecting member.
    Type: Application
    Filed: March 8, 2012
    Publication date: September 27, 2012
    Applicant: TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Mutsumi MURAOKA, Satoshi UMEMURA, Hironori KOYAMA
  • Publication number: 20120242019
    Abstract: A fluid-filled type active vibration damping device including: a pressure-receiving chamber; an equilibrium chamber; an orifice passage permitting fluid flow between the two chambers; an oscillation member oscillated by an electromagnetic actuator; an intermediate chamber; and a pressure transmission passage through which pressure fluctuations produced in the intermediate chamber is applied to the pressure-receiving chamber. The intermediate chamber is provided independently of the equilibrium chamber. The pressure transmission passage comprises a filter orifice tuned to higher frequency than the orifice passage. A movable plate is provided for limiting an amount of fluid flow through the filter orifice. A leak hole is formed for continuously interconnecting the intermediate chamber and the pressure-receiving chamber, and a liquid column resonance frequency of the leak hole is set to not more than half of that of the filter orifice.
    Type: Application
    Filed: March 8, 2012
    Publication date: September 27, 2012
    Applicant: TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Hironori KOYAMA, Mutsumi MURAOKA
  • Patent number: 8172209
    Abstract: A vibration damping device including: a rubber elastic body connecting first and second mounting members; a partition member supported on the second mounting member; a pressure-receiving chamber and an equilibrium chamber connected by a first orifice passage; an oscillating plate defining the pressure-receiving chamber; and an electromagnetic actuator for actuating the oscillating plate. The oscillating plate is constituted by a cylinder shaped hole and a piston shaped plate accommodated within the cylinder shaped hole with a gap provided therebetween. An output member of the electromagnetic actuator is linked to the piston shaped plate. A plate spring extending in an axis-perpendicular direction is disposed to an opposite side from the electromagnetic actuator with the piston shaped plate therebetween, with the oscillating plate linked to and supported in an axial direction with respect to the partition member by the plate spring.
    Type: Grant
    Filed: September 18, 2008
    Date of Patent: May 8, 2012
    Assignee: Tokai Rubber Industries, Ltd.
    Inventor: Mutsumi Muraoka
  • Patent number: 8132796
    Abstract: A fluid filled type vibration damping device wherein an elastic rubber film is disposed to partially define a primary fluid chamber disposed on one side thereof, and a pressure operating chamber is disposed on an opposite side from the primary fluid chamber with the elastic rubber film interposed therebetween. The elastic rubber film has a dome shape and an attraction face of the pressure operating chamber has an inverted dome shape, and has a negative pressure suction groove including an outer circumferential groove extending in a circumferential direction at an outer peripheral portion of the attraction face and opening to the pressure operating chamber, and a negative pressure suction bore for introducing a negative pressure to the pressure operating chamber is connected to the negative pressure suction groove.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: March 13, 2012
    Assignee: Tokai Rubber Industries, Ltd.
    Inventor: Mutsumi Muraoka
  • Patent number: 8047513
    Abstract: A vibration damping device including: a pressure-receiving chamber and an equilibrium chamber connected by a first orifice passage; a movable member disposed within the pressure-receiving chamber, to form a primary fluid chamber partly defined by a rubber elastic body, and an auxiliary fluid chamber partly defined by an oscillating plate; and a second orifice passage connecting the auxiliary fluid chamber to the equilibrium chamber. A through-hole is formed in a partition member that partitions the primary fluid chamber and the auxiliary fluid chamber, the oscillating plate is housed within the through-hole with a gap provided therebetween whereby the oscillating plate is displaceable in an axial direction within the through-hole. A stopper abutted by the oscillating plate during displacement to one axial side is provided, with the gap becoming closed off when the oscillating plate is in a state of abutment against the stopper.
    Type: Grant
    Filed: September 18, 2008
    Date of Patent: November 1, 2011
    Assignee: Tokai Rubber Industries, Ltd.
    Inventors: Mutsumi Muraoka, Hironori Koyama
  • Publication number: 20110180980
    Abstract: An active antivibration device which includes a main body, a mobile element which is elastically supported inside the main body and movable in an axial direction of the main body, and a coil which is disposed inside the main body and fixed to the main body. The mobile element includes a mobile axis body supported in the axial direction of the main body, and a first yoke, a permanent magnet and a second yoke which are held by the mobile axis body and disposed successively along an axial direction of the mobile axis body. The permanent magnet is magnetized in the axial direction of the mobile axis body and disposed between the first yoke and the second yoke.
    Type: Application
    Filed: January 28, 2011
    Publication date: July 28, 2011
    Applicants: KEIHIN CORPORATION, TOKAI RUBBER INDUSTRIES, LTD.
    Inventors: Atsushi URAYAMA, Hirozumi Kon, Hironori Koyama, Mutsumi Muraoka, Atsushi Muramatsu