Patents by Inventor Isao Hirai

Isao Hirai 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).

  • Publication number: 20090046971
    Abstract: A wheel bearing apparatus is formed as a unit of a wheel hub and a double row taper roller bearing. An outer member is formed with double row tapered outer raceway surfaces, each opened axially outward, on its inner circumference. An inner member, including the wheel hub, has a wheel mounting flange integrally formed at one end of the wheel hub. A cylindrical portion axially extends from the wheel mounting flange. At least one inner ring is fit onto the cylindrical portion of the wheel hub via a predetermined interference. Each inner ring is formed with one of the tapered double row inner raceway surfaces on its outer circumference. The inner raceway surfaces are arranged opposite to one of the double row outer raceway surfaces. On its larger outer diameter side, the inner ring has a larger flange portion to guide the tapered rollers. Double row tapered rollers are rollably arranged between the outer and inner raceway surfaces, via cages.
    Type: Application
    Filed: October 21, 2008
    Publication date: February 19, 2009
    Applicant: NTN Corporation
    Inventors: Isao Hirai, Takayuki Norimatsu, Hiroya Kato, Akira Fujimura, Kikuo Fukada
  • Publication number: 20090028485
    Abstract: A vehicle wheel bearing apparatus is formed as a unit and has a wheel hub with a wheel mounting flange at one end. A cylindrical portion extends from the wheel mounting flange, via a shoulder portion. A wheel bearing, formed by a double row rolling bearing, is press fit onto the cylindrical portion of the wheel hub. The wheel bearing has an outer member formed with double row outer raceway surfaces on its inner circumferential surface. A pair of inner rings, formed with inner raceway surfaces, is arranged opposite to the double row outer raceway surfaces. The rings are press fit onto the cylindrical portion of the wheel hub, via a predetermined interference. One ring abuts the shoulder portion. Double row rolling elements are freely rollably contained between the opposed inner and outer raceway surfaces, via cages. The inner rings are axially immovably secured by a caulked portion. The caulked portion is formed by plastically radially outwardly deforming the end portion of the cylindrical portion.
    Type: Application
    Filed: August 7, 2008
    Publication date: January 29, 2009
    Applicant: NTN Corporation
    Inventors: Takayuki Norimatsu, Hiroya Kato, Akira Fujimura, Isao Hirai, Kikuo Fukada
  • Publication number: 20090003746
    Abstract: A vehicle wheel bearing apparatus has an outer member formed with a body mounting flange on its outer circumferential surface. The body mounting flange is to be mounted on a knuckle of the vehicle. The outer member inner circumference includes double row outer raceway surfaces. An inner member includes a wheel hub with a wheel mounting flange formed on one end. A cylindrical portion extends from the wheel mounting flange. At least one inner ring is press-fit onto the cylindrical portion of the wheel hub. The inner ring outer circumference is formed with an inner raceway surface arranged opposite to the double row outer raceway surfaces. Double row rolling elements are freely rollably contained between the outer raceway surfaces and inner raceway surfaces of the outer member and the inner members. Seals are mounted within annular openings formed between the outer member and the inner member. The inner ring is axially secured relative to the wheel hub by a caulked portion.
    Type: Application
    Filed: September 5, 2008
    Publication date: January 1, 2009
    Applicant: NTN Corporation
    Inventors: Takayuki Norimatsu, Akira Fujimura, Isao Hirai, Shinji Morita
  • Patent number: 7452136
    Abstract: A vehicle wheel bearing apparatus which can increase the strength and durability of the hub wheel under rotary bending conditions as well as lighten the apparatus without changing the configuration and dimension of the wheel mounting flange and without causing surface run-out has an outer member formed with double row outer raceway surfaces on its inner peripheral surface. An inner member is formed with double row inner raceway surfaces arranged opposite to the double row outer raceway surfaces. Double row rolling elements are freely rollably contained between the outer and inner raceway surfaces, respectively, of the outer and inner members. A wheel mounting flange is integrally formed with either one of the outer or inner members. At least one of the outer and inner members, on which the wheel mounting flange is formed, is heat treated and their raceway surfaces are hardened by quenching to a predetermined surface hardness.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: November 18, 2008
    Assignee: NTN Corporation
    Inventors: Isao Hirai, Takayasu Takubo, Kazuhiko Yoshida
  • Publication number: 20070201783
    Abstract: A bearing device for a wheel enabling the easy control of quality since there is no possibility of cracking even if caulking is applied thereto. The bearing device comprises an outer ring having double rows of raceway surfaces on the inner periphery thereof, an inner member having raceway surfaces opposed to the raceway surfaces, and balls interposed between the double rows of raceway surfaces opposed to each other. The inner member further comprises a HUB ring and an inner ring. Caulking is applied to the HUB ring to join it to the inner ring. The grain size number of the austenite grains of a caulked section is at least 6.
    Type: Application
    Filed: March 3, 2005
    Publication date: August 30, 2007
    Inventors: Isao Hirai, Takayasu Takubo, Kazuhiko Yoshida
  • Publication number: 20070187004
    Abstract: A hub ring and/or an outer ring constituting a bearing device for a wheel, which is formed of a steel which contains 0.45 to 0.70 mass % of C and at least one of V, Nb and Ti in a total amount of 0.3 mass % or less, wherein a micro structure of a part being not surface-hardening-treated contains a ferrite in 15 to 30 area % and contains a particulate ferrite.
    Type: Application
    Filed: March 3, 2005
    Publication date: August 16, 2007
    Inventors: Isao Hirai, Takayasu Takubo, Kazuhiko Yoshida
  • Publication number: 20070081751
    Abstract: A wheel bearing apparatus has an outer member formed with double row outer raceway surfaces on its inner circumferential surface. An inner member includes a wheel hub integrally formed with a wheel mounting flange at one end and a cylindrical portion axially extending from the wheel mounting flange. At least one inner ring is fit onto the cylindrical portion of the wheel hub. The inner ring is formed with a double row inner raceway surfaces on its outer circumferential surface. The double row inner raceway surfaces are arranged opposite to the double row outer raceway surfaces. Double row rolling elements are rollably arranged between the outer and inner raceway surfaces, via cages. Seals are mounted in openings or annular spaces formed between the outer member and the inner member. At least an inner-side seal of the seals has a slinger and an annular sealing plate. Each has a substantially ā€œLā€ shaped cross-section arranged opposite to one another.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 12, 2007
    Inventors: Takayuki Norimatsu, Kenrou Adachi, Isao Hirai
  • Publication number: 20070076994
    Abstract: A wheel bearing apparatus has an outer member formed with double row outer raceway surfaces on its inner circumferential surface. An inner member includes a wheel hub with a wheel mounting flange integrally formed at one end and a cylindrical portion axially extending from the wheel mounting flange. At least one inner ring is fit onto the cylindrical portion of the wheel hub. The inner ring is formed with double row inner raceway surfaces on its outer circumferential surface. The double row inner raceway surfaces are arranged opposite to the double row outer raceway surfaces. Double row rolling elements are rollably arranged between the outer and inner raceway surfaces, via cages. A seal is mounted on one end of the outer member. The seal has integrally formed side lips adapted to be in sliding contact with the wheel hub. The base of the wheel mounting flange is formed to have a curved surface, in cross-section, of a circular arc.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 5, 2007
    Inventors: Takayuki Norimatsu, Hiroaki Itakura, Hironori Imanaka, Syougo Suzuki, Isao Hirai, Hiroya Kato, Akira Fujimura, Kikuo Fukada
  • Publication number: 20040252927
    Abstract: A vehicle wheel bearing apparatus which can increase the strength and durability of the hub wheel under rotary bending conditions as well as lighten the apparatus without changing the configuration and dimension of the wheel mounting flange and without causing surface run-out has an outer member formed with double row outer raceway surfaces on its inner peripheral surface. An inner member is formed with double row inner raceway surfaces arranged opposite to the double row outer raceway surfaces. Double row rolling elements are freely rollably contained between the outer and inner raceway surfaces, respectively, of the outer and inner members. A wheel mounting flange is integrally formed with either one of the outer or inner members. At least one of the outer and inner members, on which the wheel mounting flange is formed, is heat treated and their raceway surfaces are hardened by quenching to a predetermined surface hardness.
    Type: Application
    Filed: June 10, 2004
    Publication date: December 16, 2004
    Inventors: Isao Hirai, Takayasu Takubo, Kazuhiko Yoshida