Patents by Inventor Junichi Izumino

Junichi Izumino 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: 8491398
    Abstract: A manufacturing method for a tripod type constant velocity universal joint includes, when forging a raw-shaped material corresponding to each of three journals into a journal shape using a molding surface of a die and in a state where a relief portion is provided on a raw-shaped-material-leading-end-side of the die, molding an outer peripheral surface of the raw-shaped material into a projected round shape. The molding occurring with a tapered surface formed on the molding surface with which the outer peripheral surface of the raw-shaped material is held in contact and a recessed round surface formed between the molding surface and the tapered surface.
    Type: Grant
    Filed: April 2, 2010
    Date of Patent: July 23, 2013
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Kenji Konaka, Hiroshi Murakami, Akira Sera, Jiahua Miao, Shunsuke Makino
  • Patent number: 8342969
    Abstract: A tripod-type constant-velocity universal joint has a journal raw profile with reduced weight and a reduced number of manufacturing steps. A leading end corner portion of the journal raw profile is held with use of a die and forged. By the forging, at the part including an elliptically longitudinal side relatively on a leading end portion side of an outer peripheral surface of each of journals, edge portions reducing a lateral sectional area of each of the journals toward a leading end side thereof are formed, and tapered surfaces are formed on the leading end side of the edge portions. Centering on each of the journals is performed by causing two points on an elliptically longitudinal side of the edge portions to abut against a centering jig.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: January 1, 2013
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Kenji Konaka
  • Publication number: 20120021842
    Abstract: Provided is a manufacturing method for a tripod type constant velocity universal joint including: an outer joint member having an inner peripheral surface provided with: three track grooves extending in an axial direction; and roller-guide surfaces extending in the axial direction on both sides of each of the three track grooves; a tripod member including three journals each projected into a radial direction; and a roller unit supported rotatably around each of the three journals of the tripod member and inserted rollably in each of the three track grooves of the outer joint member, the manufacturing method including, when forging a raw-shaped material corresponding to each of the three journals into a journal shape with use of a molding surface of a die, under a state in which a relief portion is provided on a raw-shaped-material-leading-end-side of the die, molding an outer peripheral surface of the raw-shaped material into a projected round shape with use of a tapered surface formed on the molding surface
    Type: Application
    Filed: April 2, 2010
    Publication date: January 26, 2012
    Inventors: Junichi Izumino, Kenji Konaka, Hiroshi Murakami, Akira Sera, Jiahua Miao, Shunsuke Makino
  • Patent number: 8029373
    Abstract: A fixed constant velocity universal joint of a structure, which easily allows incorporation of an inner ring into a cage without impairing a function of the joint, is provided.
    Type: Grant
    Filed: November 15, 2006
    Date of Patent: October 4, 2011
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Manabu Hoshino
  • Publication number: 20110130211
    Abstract: Provided are a tripod-type constant-velocity universal joint which is capable of reducing weight of a journal raw profile to thereby reduce the number of manufacturing steps and in which forging of journals is facilitated, and a method of manufacturing the same. A leading end corner portion (32) of a journal raw profile (54) is held with use of a die (X) and forged. In this case, in a state in which a relief portion (35) is provided on a leading end side of the die (X), a part including an elliptically longitudinal side of the leading end corner portion (32) of the journal raw profile (54) is held with use of the die (X). In the die (X), inner walls of a part at which the leading end corner portion (32) of the journal raw profile (54) is held constitute tapering surfaces (33).
    Type: Application
    Filed: July 29, 2009
    Publication date: June 2, 2011
    Inventors: Junichi Izumino, Kenji Konaka
  • Patent number: 7708644
    Abstract: A tripod constant velocity universal joint includes among others an inner joint member having a boss 22 and journals 24 radially protruding from the boss, a radius of curvature R1 as viewed in a cross section of a journal bottom part 23 connecting the boss 22 to the journal 24 and as measured at opposing locations in a circumferential direction of the joint is larger than a radius of curvature R2 of the journal bottom part as viewed in its cross section and as measured at opposing locations in an axial direction of the joint and R1 gradually decreases down to R2.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: May 4, 2010
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Minoru Ishijima
  • Patent number: 7704148
    Abstract: In a tripod type constant velocity joint, in order to produce a recovery couple to correct the inclination of the rolling direction of a roller and to reduce surface pressure without using angular contact provided by a Gothic arch-shaped roller guide surface, it is arranged that where r1 and r2 are the minimum and maximum values, respectively, of the radius of curvature of the generatrix for the outer peripheral surface of the roller within the range where solid contact is effected by elastic deformation of the contact section between the roller and the roller guide surface under a predetermined torque load with respect to the radius of curvature of the roller guide surface, the radius of curvature (r) of the generatrix be set in the range r1?r?r2.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: April 27, 2010
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Kenta Yamazaki
  • Patent number: 7682253
    Abstract: A tripod type constant velocity joint including a hollow cylindrical housing fixed to the end of a first rotary shaft and formed with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, and roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: March 23, 2010
    Assignee: NTN Corporation
    Inventors: Minoru Ishijima, Kenta Yamazaki, Junichi Izumino
  • Patent number: 7654908
    Abstract: A tripod type constant velocity universal joint that includes an outer joint member having three track grooves axially extending on an inner circumferential surface thereof; an inner joint member having three radially projecting trunnions; a boot fitted to an outer periphery of the outer joint member at an end portion and to a shaft extended from the inner joint member at another end portion to seal an inner region of the joint; wherein the outer joint member includes a first reduced-thickness portion on an outer periphery thereof in a region corresponding to the region between the track grooves, and a second reduced-thickness portion on an outer periphery thereof in a region corresponding to the region where the track grooves are located; and wherein the second reduced-thickness portion is of a groove shape axially extending with respect to the outer joint member.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: February 2, 2010
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Minoru Ishijima
  • Publication number: 20090258716
    Abstract: Provided is a fixed constant velocity universal joint of a structure, which easily allows incorporation of an inner ring into a cage without impairing a function of the joint.
    Type: Application
    Filed: November 15, 2006
    Publication date: October 15, 2009
    Inventors: Junichi Izumino, Manabu Hoshino
  • Patent number: 7473181
    Abstract: The present invention provides a lightweight, compact, and low-cost tripod type constant velocity universal joint while maintaining strength of overall tripod type constant velocity universal joint. The dimensional ratio of each component of the tripod type constant velocity universal joint is set as follows: 0.80<Dor<0.90, 0.105<Tor<0.115, 0.025<fir<0.045, 0.025<t2r<0.075, 0.53<Dir<0.63, 0.065<Tir<0.085, 0.32<Dj1r<0.42, and 0.32<Dj2r<0.35. In this event, the subscript “r” means that each dimension is divided by the trunnion journal pitch circle diameter D (=PCD) of the joint.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: January 6, 2009
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Minoru Ishijima
  • Publication number: 20080194341
    Abstract: A tripod type constant velocity universal joint that includes an outer joint member having three track grooves axially extending on an inner circumferential surface thereof; an inner joint member having three radially projecting trunnions; a boot fitted to an outer periphery of the outer joint member at an end portion and to a shaft extended from the inner joint member at another end portion to seal an inner region of the joint; wherein the outer joint member includes a first reduced-thickness portion on an outer periphery thereof in a region corresponding to the region between the track grooves, and a second reduced-thickness portion on an outer periphery thereof in a region corresponding to the region where the track grooves are located; and wherein the second reduced-thickness portion is of a groove shape axially extending with respect to the outer joint member.
    Type: Application
    Filed: April 11, 2008
    Publication date: August 14, 2008
    Applicant: NTN CORPORATION
    Inventors: Junichi Izumino, Minoru Ishijima
  • Publication number: 20080161116
    Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher
    Type: Application
    Filed: March 14, 2008
    Publication date: July 3, 2008
    Inventors: Minoru Ishijima, Kenta Yamazaki, Junichi Izumino
  • Patent number: 7357723
    Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: April 15, 2008
    Assignee: NTN Corporation
    Inventors: Minoru Ishijima, Kenta Yamazaki, Junichi Izumino
  • Patent number: 7201664
    Abstract: A fixed constant velocity joint is provided, which is suitable for an application where a rotational backlash should be avoided. A pressing member is attached to a shaft, and simultaneously a receiving member is attached to a cage. Then, an elastic force of an elastic member elastically bring a pressing part of the pressing member in contact with a receiving part of the receiving member. As a result, an inner race and a cage relatively travel in the axial direction, balls are pushed toward a direction along which wedge-shape ball tracks narrow, and consequently a track clearance in the axial direction decreases.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: April 10, 2007
    Assignee: NTN Corporation
    Inventors: Kenta Yamazaki, Junichi Izumino, Kenji Terada, Hisaaki Kura
  • Publication number: 20070004522
    Abstract: A tripod type constant velocity joint comprising a hollow cylindrical housing fixed to the end of a first rotary shaft and formed at the inner peripheral surface thereof with axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on the inner peripheral surface, a tripod consisting of a boss fixed to the end of a second rotary shaft, and end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss, a roller assemblies each consisting of an inner roller swingably fitted at the inner peripheral surface thereof on the spherical outer peripheral surface of the trunnion journal, and an outer roller supported for rotation and axial movement on the outer peripheral surface of the inner roller through needle rollers, wherein the outer rollers are received in the recessed grooves in the housing and are rollable axially of the housing, each recessed groove consists of guide surfaces contacting the outer peripher
    Type: Application
    Filed: September 5, 2006
    Publication date: January 4, 2007
    Inventors: Minoru Ishijima, Kenta Yamazaki, Junichi Izumino
  • Patent number: 7137895
    Abstract: Tripod type constant velocity joint has a hollow cylindrical housing fixed to the end of a first shaft and has axially extending recessed grooves opened at one axial end and located at circumferentially trisectional positions on an inner peripheral surface. A tripod has a boss fixed to the end of a second shaft with end-spherical trunnion journals radially projecting from circumferentially trisectional positions on the boss. Roller assemblies each have an inner roller fitted on the spherical surface of the trunnion journal and an outer roller supported for rotation and axial movement on the inner roller. The outer rollers are received in the recessed grooves and rollable axially of the housing. Each recessed groove has guide surfaces contacting the outer surface of the outer roller. Guide shoulder surfaces guide the outer roller axially of the housing. A relief is locally formed along a forged parting line of the trunnion journal.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: November 21, 2006
    Assignee: NTN Corporation
    Inventors: Minoru Ishijima, Kenta Yamazaki, Junichi Izumino
  • Patent number: 7121950
    Abstract: A tripod type constant velocity universal joint that can suppress generation of shudder by reducing the 3rd order cyclic axial force and has high rotation durability. In a double-roller tripod type constant velocity universal joint, a track gap ?1 between one of the roller guiding surfaces formed on both sides of a track groove, which is on the no-load applied side, and an outer circumferential surface of an outer roller is set to satisfy ?1>0.03/A. Also, a shoulder gap ?2 between a guide shoulder surface formed at the bottom of the track groove and a side surface of the outer roller is set to satisfy ?2>0.15×A. In both the expressions, a degree of torus A is defined as a ratio of a radius of curvature r of a generatrix of the outer circumferential surface to a radius R of an outer circumference of the outer roller (A=r/R).
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: October 17, 2006
    Assignee: NTN Corporation
    Inventors: Junichi Izumino, Minoru Ishijima, Kenta Yamazaki
  • Publication number: 20060223642
    Abstract: The present invention provides a lightweight, compact, and low-cost tripod type constant velocity universal joint while maintaining strength of overall tripod type constant velocity universal joint. The dimensional ratio of each component of the tripod type constant velocity universal joint is set as follows: 0.80<Dor<0.90, 0.105<Tor<0.115, 0.025<t1r<0.045, 0.025<t2r<0.075, 0.53<Dir<0.63, 0.065<Tir<0.085, 0.32<Dj1r<0.42, and 0.32<Dj2r<0.35. In this event, the subscript “r” means that each dimension is divided by the trunnion journal pitch circle diameter D (=PCD) of the joint.
    Type: Application
    Filed: March 17, 2006
    Publication date: October 5, 2006
    Inventors: Junichi Izumino, Minoru Ishijima
  • Publication number: 20060217205
    Abstract: A tripod constant velocity universal joint comprises among others an inner joint member having a boss 22 and journals 24 radially protruding from the boss, a radius of curvature R1 as viewed in a cross section of a journal bottom part 23 connecting the boss 22 to the journal 24 and as measured at locations opposing circumferentially of the joint is larger than a radius of curvature R2 of the journal bottom part as viewed in its cross section and as measured at locations opposing axially of the joint and R1 gradually decreases down to R2.
    Type: Application
    Filed: March 9, 2006
    Publication date: September 28, 2006
    Inventors: Junichi Izumino, Minoru Ishijima