Patents by Inventor Eiichi Nakamizo

Eiichi Nakamizo 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: 10408267
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: September 22, 2017
    Date of Patent: September 10, 2019
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 10190576
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between said outer ring and said inner ring; and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding said roller. A connection part extends in a circumferential direction so as to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between said outer ring and said inner ring, in which a corner of a circumferential end face is chamfered. Also provided is a spacer arranged between the circumferentially arranged first retainer segment and last retainer segment, wherein a chamfered part is provided at a corner of a circumferential spacer end face of the space. The roller bearing can be used in a main shaft support structure of a wind-power generator.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: January 29, 2019
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20180010639
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Application
    Filed: September 22, 2017
    Publication date: January 11, 2018
    Inventors: Tatsuya OMOTO, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Patent number: 9810263
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: May 16, 2014
    Date of Patent: November 7, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20170306929
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between said outer ring and said inner ring; and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding said roller. A connection part extends in a circumferential direction so as to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between said outer ring and said inner ring, in which a corner of a circumferential end face is chamfered. Also provided is a spacer arranged between the circumferentially arranged first retainer segment and last retainer segment, wherein a chamfered part is provided at a corner of a circumferential spacer end face of the space. The roller bearing can be used in a main shaft support structure of a wind-power generator.
    Type: Application
    Filed: July 6, 2017
    Publication date: October 26, 2017
    Inventors: Tatsuya OMOTO, Shoichi HIOKI, Mitsuo SASABE, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Patent number: 9732734
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding the roller, and connection parts and extending in a circumferential direction to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part is positioned at an circumferential end of the retainer segment. Here, a circumferential outer side end face of the column part positioned at the end is flat, and a circumferential inner side end face of the column part positioned at said end is provided with a recess recessed in the circumferential direction to reduce the thickness of the column part.
    Type: Grant
    Filed: November 5, 2014
    Date of Patent: August 15, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 9664231
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: May 30, 2017
    Assignee: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20150226262
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Application
    Filed: April 22, 2015
    Publication date: August 13, 2015
    Inventors: Tatsuya OMOTO, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20150056079
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding the roller, and connection parts and extending in a circumferential direction to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part is positioned at an circumferential end of the retainer segment. Here, a circumferential outer side end face of the column part positioned at the end is flat, and a circumferential inner side end face of the column part positioned at said end is provided with a recess recessed in the circumferential direction to reduce the thickness of the column part.
    Type: Application
    Filed: November 5, 2014
    Publication date: February 26, 2015
    Inventors: Tatsuya OMOTO, Shoichi HIOKI, Mitsuo SASABE, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Patent number: 8905646
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding the roller, and connection parts and extending in a circumferential direction to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part is positioned at an circumferential end of the retainer segment. Here, a circumferential outer side end face of the column part positioned at the end is flat, and a circumferential inner side end face of the column part positioned at said end is provided with a recess recessed in the circumferential direction to reduce the thickness of the column part.
    Type: Grant
    Filed: November 21, 2012
    Date of Patent: December 9, 2014
    Assignee: NTN Corporation
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20140248018
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Application
    Filed: May 16, 2014
    Publication date: September 4, 2014
    Applicant: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Patent number: 8764304
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: July 1, 2014
    Assignee: NTN Corporation
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20130078098
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments having a plurality of column parts extending in a direction along a shaft so as to form a pocket for holding the roller, and connection parts and extending in a circumferential direction to connect the plurality of column parts, and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part is positioned at an circumferential end of the retainer segment. Here, a circumferential outer side end face of the column part positioned at the end is flat, and a circumferential inner side end face of the column part positioned at said end is provided with a recess recessed in the circumferential direction to reduce the thickness of the column part.
    Type: Application
    Filed: November 21, 2012
    Publication date: March 28, 2013
    Inventors: Tatsuya OMOTO, Shoichi HIOKI, Mitsuo SASABE, Eiichi NAKAMIZO, Tomoya SAKAGUCHI
  • Patent number: 8382380
    Abstract: Tapered rollers are retained between outer and inner rings by a retainer to be circumferentially spaced apart from each other. The inner ring has a raceway on its outer surface and includes small and large-diameter flanges at the small- and large-diameter ends of the raceway, respectively. The retainer includes two annular portions and crossbars extending between the annular portions. Its radially inner surface is located radially inwardly of the pitch cone of the tapered rollers to increase the thickness of the crossbars and the axial thickness of the small-diameter annular portion. The conical surface defined by the outer surfaces of the crossbars has an inclination angle that is greater than the central angle of the bearing to increase the volume of the crossbars. The rigidity of the retainer is thus increased.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: February 26, 2013
    Assignee: NTN Corporation
    Inventors: Eiichi Nakamizo, Junichi Hattori, Hideshi Nishiwaki, Tatsuya Omoto, Michio Hori
  • Publication number: 20110249931
    Abstract: A tapered roller bearing (31) has pockets to house tapered rollers (34) and includes a plurality of retainer segments (11a) to (11d) arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32) and an inner ring (33). The retainer segments (11a) to (11d) include at least a first retainer segment having a first circumferential length, and a second retainer segment having a second circumferential length different from the first circumferential length. After the retainer segments (11a) to (11d) have been arranged in the circumferential direction without space therebetween, a circumferential clearance (39) is provided between the retainer segment (11a) arranged first and the retainer segment (11d) arranged last. A circumferential range of the clearance is larger than 0.08% and smaller than 0.10% of a circumference of a circle passing through a center of the retainer segment at room temperature.
    Type: Application
    Filed: September 1, 2009
    Publication date: October 13, 2011
    Applicant: NTN CORPORATION
    Inventors: Tatsuya Omoto, Eiichi Nakamizo
  • Publication number: 20100316321
    Abstract: The object is to provide a miniature-sized tapered roller bearing that includes an inner race having an inner diameter of not more than 9 mm and that ensures high dynamic load rating. The ratio of the average diameter DRAVE of the tapered rollers 3 to the inner diameter DIi of the inner race 1, i.e. DRAVE/DIi is set to 0.45 to 0.70 to ensure high dynamic load rating with a miniature-sized tapered roller bearing of which the inner race 1 has an inner diameter of not less than 9 mm.
    Type: Application
    Filed: November 30, 2007
    Publication date: December 16, 2010
    Inventors: Eiichi Nakamizo, Hideshi Nishiwaki, Tsukasa Toyoda
  • Publication number: 20090324410
    Abstract: A tapered roller bearing (31a) has a plurality of retainer segments (11a, 11d) each having a pocket to house a tapered roller (34a), and arranged so as to be continuously lined with each other in a circumferential direction between an outer ring (32a) and an inner ring (33a). The retainer segment (11a, 11d) is formed of a resin containing a filler material to lower a thermal linear expansion coefficient. In addition, a clearance (39a) is provided between the first retainer segment (11a) and the last retainer segment (11d) after the plurality of retainer segments (11a, 11d) have been arranged in the circumferential direction without providing any clearance. Here a circumferential range (R) of the clearance (39a) is larger than 0.075% of a circumference of a circle passing through a center of the retainer segment (11a, 11d) and smaller than 0.12% thereof at room temperature.
    Type: Application
    Filed: September 4, 2007
    Publication date: December 31, 2009
    Inventors: Tatsuya Omoto, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20090046974
    Abstract: A roller bearing comprises an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a plurality of retainer segments (11a) having a plurality of column parts (14a) and (14b) extending in a direction along a shaft so as to form a pocket (13a) for holding the roller, and connection parts (15a) and (15b) extending in a circumferential direction so as to connect the plurality of column parts (14a) and (14b), and continuously lined with each other in the circumferential direction between the outer ring and the inner ring. The column part (14a) is positioned at an circumferential end of the retainer segment (11a). Here, a circumferential outer side end face (21a) of the column part (14a) positioned at the end is flat, and a circumferential inner side end face (25a) of the column part (14a) positioned at said end is provided with a recess (23a) recessed in the circumferential direction so as to reduce the thickness of the column part (14a).
    Type: Application
    Filed: February 26, 2007
    Publication date: February 19, 2009
    Inventors: Tatsuya Omoto, Shoichi Hioki, Mitsuo Sasabe, Eiichi Nakamizo, Tomoya Sakaguchi
  • Publication number: 20080193067
    Abstract: A tapered roller bearing is proposed for supporting each of planetary rotary members that rotate about a common axis and their own axes. The tapered roller bearing includes an inner ring spacer provided adjacent to the small-diameter flange of the inner ring. The retainer retaining the tapered rollers in position includes small- and large-diameter annular portions and bridges connecting the two annular portions together. The retainer further includes a disk portion extending radially inwardly from the axially outer end of the small-diameter annular portion, and a third annular portion extending axially outwardly from the radially inner end of the disk portion. The third annular portion has a radially inner guided surface guided by the radially outer guiding surface of the inner ring spacer. A hardened surface layer and a lubricating film are formed on the radially outer guiding surface of the inner ring spacer.
    Type: Application
    Filed: January 28, 2008
    Publication date: August 14, 2008
    Inventors: Junichi Hattori, Michio Hori, Eiichi Nakamizo, Tsukasa Toyoda
  • Publication number: 20070047865
    Abstract: A plurality of tapered rollers are retained between an outer ring and an inner ring by a retainer so as to be circumferentially spaced apart from each other. The inner ring is formed with a raceway on its outer surface and includes a small-diameter flange and a large-diameter flange at the small- and large-diameter ends of the raceway, respectively. The retainer includes two annular portions and crossbars extending between the annular portions. Its radially inner surface is located radially inwardly of the pitch cone of the tapered rollers (conical surface defined by the axes of the tapered rollers) to increase the thickness of the crossbars as well as the axial thickness of the small-diameter annular portion. The rigidity of the retainer thus increases.
    Type: Application
    Filed: August 23, 2006
    Publication date: March 1, 2007
    Inventors: Eiichi Nakamizo, Junichi Hattori, Hideshi Nishiwaki, Tatsuya Omoto, Michio Hori