Patents by Inventor Masaaki Nagayasu

Masaaki Nagayasu 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: 9180739
    Abstract: A plurality of blocks is provided in a tread portion and a plurality of sipes is provided in a tread surface of the blocks. In the sipes, protrusions are formed on a first sipe wall surface of mutually opposing sipe wall surfaces and recesses that engage with the protrusions are formed on a second sipe wall surface. Collapsing of the portions of the blocks sandwiched by the sipes is suppressed due to the engaging of the protrusions and the recesses. A height of the protrusions provided on the sipe wall surfaces of the sipes located at the edges in the tire circumferential direction is greater than a height of the protrusions provided on the sipe wall surfaces of the other sipes. Specifically, a force that works to suppress bending deformation increases and collapsing of the portions of the blocks located at the edges in the tire circumferential direction is suppressed.
    Type: Grant
    Filed: July 14, 2011
    Date of Patent: November 10, 2015
    Assignee: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: 9162535
    Abstract: A pneumatic tire includes sipes extending in a tire width direction on a road contact surface of blocks, the sipes having at least one end open to a circumferential main groove. The sipes are positioned at an edge portion of the blocks, and have a first sipe portion open to the circumferential main groove and a second sipe portion positioned at a center portion of the blocks. The first sipe portion has a linear form when viewed as a cross-section from a direction perpendicular to a sipe length direction, and has a pair of mutually mating, opposing first sipe wall faces with a protrusion and a recess respectively disposed thereon. The second sipe portion has a form bent in the sipe width direction when viewed as a cross-section from a direction perpendicular to the sipe length direction, and has a pair of mating mutually opposing second sipe wall faces.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: October 20, 2015
    Assignee: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: 9156317
    Abstract: A pneumatic tire wherein a sipe includes protrusions on a first sipe wall face of mutually opposing sipe wall faces and recesses that mate with the protrusions in a second sipe wall face. Additionally, in a projection figure of the protrusions with the sipe wall faces in an expanded state, a relationship between a placement density X of the protrusions in a region that extends up to half of a sipe depth H from an opening of the sipe and a placement density Y of the protrusions in a region that extends up to half of the sipe depth H from a bottom of the sipe is X>Y.
    Type: Grant
    Filed: June 21, 2011
    Date of Patent: October 13, 2015
    Assignee: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Publication number: 20150191051
    Abstract: A pneumatic tire includes blocks arranged in the tread center region that is X % (30?X?70) of the tread contact width TW with the tire equator C as center are formed elongated in the tire circumferential direction so that the block ratio is not less than 1.5. At least one end in the longitudinal direction of the sipes provided in the blocks connects to a longitudinal groove. A protrusion and a recess that can engage with each other are provided on the sipe wall surfaces that face each other constituting the sipes, at the end portion in the longitudinal direction of the sipes that connect with the longitudinal groove.
    Type: Application
    Filed: June 3, 2013
    Publication date: July 9, 2015
    Applicant: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: 9061550
    Abstract: A pneumatic tire has a good balance between on-ice and on-snow performances. The tire includes a tread portion having longitudinal and lateral grooves defining block rows. Each block in the block rows includes sipes. A length of each block in the first and second block rows is not less than 1.5 times and not more than 2.5 times a length of each third block row block. A width of each second block row block is larger than a width of each first block row block. The lateral grooves defining the first and second block row blocks are offset in the tire circumferential direction by not less than 0.2 times and not more than 0.8 times the length of each first block row block. The lateral grooves defining the second and third block row blocks communicate with each other while inclining in the same direction.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: June 23, 2015
    Assignee: THE YOKOHAMA RUBBER CO., LTD.
    Inventors: Masaaki Nagayasu, Hiroshi Furusawa
  • Patent number: 8875760
    Abstract: A plurality of sipes extending in a tire width direction are provided in a tread surface of a block. In the sipes, protrusions are formed on a first sipe wall surface of mutually opposing sipe wall surfaces and recesses that engage with the protrusions are formed on a second sipe wall surface. Collapse of portions of the block sandwiched by the sipes is suppressed due to engagement of the protrusions and the recesses. A height of protrusions positioned on an upper portion in the depth direction of the sipes is greater than a height of protrusions positioned on a lower portion.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: November 4, 2014
    Assignee: The Yokohama Rubber Co., Ltd.
    Inventor: Masaaki Nagayasu
  • Patent number: 8844592
    Abstract: A pneumatic tire improved in on-ice performance and on-snow performance in good balance. The pneumatic tire includes a tread portion extending in a tire circumferential direction and forming a ring shape, a pair of sidewall portions on both sides of the tread portion, respectively, and a pair of bead portions on inner sides of the sidewall portions in a tire radial direction, respectively. The tread portion includes a plurality of longitudinal grooves extending in the tire circumferential direction and a plurality of lateral grooves extending in a tire width direction. The longitudinal and lateral grooves define a plurality of block rows each including a plurality of blocks. Each of the plurality of blocks included in at least one of the block rows includes at least three closed grooves including at least one first closed groove and at least one second closed groove.
    Type: Grant
    Filed: May 17, 2011
    Date of Patent: September 30, 2014
    Assignee: The Yokohama Rubber Co., Ltd.
    Inventors: Masaaki Nagayasu, Yoshimasa Hashimoto, Hiroshi Furusawa, Kenichirou Endou, Kenichi Sato
  • Publication number: 20120285591
    Abstract: A pneumatic tire has a good balance between on-ice and on-snow performances. The tire includes a tread portion having longitudinal and lateral grooves defining block rows. Each block in the block rows includes sipes. A length of each block in the first and second block rows is not less than 1.5 times and not more than 2.5 times a length of each third block row block. A width of each second block row block is larger than a width of each first block row block. The lateral grooves defining the first and second block row blocks are offset in the tire circumferential direction by not less than 0.2 times and not more than 0.8 times the length of each first block row block. The lateral grooves defining the second and third block row blocks communicate with each other while inclining in the same direction.
    Type: Application
    Filed: September 20, 2011
    Publication date: November 15, 2012
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventors: Masaaki NAGAYASU, Hiroshi FURUSAWA
  • Publication number: 20120180920
    Abstract: A pneumatic tire includes sipes extending in a tire width direction on a road contact surface of blocks, the sipes having at least one end open to a circumferential main groove. The sipes are positioned at an edge portion of the blocks, and have a first sipe portion open to the circumferential main groove and a second sipe portion positioned at a center portion of the blocks. The first sipe portion has a linear form when viewed as a cross-section from a direction perpendicular to a sipe length direction, and has a pair of mutually mating, opposing first sipe wall faces with a protrusion and a recess respectively disposed thereon. The second sipe portion has a form bent in the sipe width direction when viewed as a cross-section from a direction perpendicular to the sipe length direction, and has a pair of mating mutually opposing second sipe wall faces.
    Type: Application
    Filed: September 28, 2011
    Publication date: July 19, 2012
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventor: Masaaki Nagayasu
  • Publication number: 20120118454
    Abstract: A pneumatic tire improved in on-ice performance and on-snow performance in good balance. The pneumatic tire includes a tread portion extending in a tire circumferential direction and forming a ring shape, a pair of sidewall portions on both sides of the tread portion, respectively, and a pair of bead portions on inner sides of the sidewall portions in a tire radial direction, respectively. The tread portion includes a plurality of longitudinal grooves extending in the tire circumferential direction and a plurality of lateral grooves extending in a tire width direction. The longitudinal and lateral grooves define a plurality of block rows each including a plurality of blocks. Each of the plurality of blocks included in at least one of the block rows includes at least three closed grooves including at least one first closed groove and at least one second closed groove.
    Type: Application
    Filed: May 17, 2011
    Publication date: May 17, 2012
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventors: Masaaki NAGAYASU, Yoshimasa HASHIMOTO, Hiroshi FURUSAWA, Kenichirou ENDOU, Kenichi SATO
  • Publication number: 20120018069
    Abstract: A plurality of blocks is provided in a tread portion and a plurality of sipes is provided in a tread surface of the blocks. In the sipes, protrusions are formed on a first sipe wall surface of mutually opposing sipe wall surfaces and recesses that engage with the protrusions are formed on a second sipe wall surface. Collapsing of the portions of the blocks sandwiched by the sipes is suppressed due to the engaging of the protrusions and the recesses. A height of the protrusions provided on the sipe wall surfaces of the sipes located at the edges in the tire circumferential direction is greater than a height of the protrusions provided on the sipe wall surfaces of the other sipes. Specifically, a force that works to suppress bending deformation increases and collapsing of the portions of the blocks located at the edges in the tire circumferential direction is suppressed.
    Type: Application
    Filed: July 14, 2011
    Publication date: January 26, 2012
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventor: Masaaki Nagayasu
  • Publication number: 20110315290
    Abstract: A pneumatic tire wherein a sipe includes protrusions on a first sipe wall face of mutually opposing sipe wall faces and recesses that mate with the protrusions in a second sipe wall face. Additionally, in a projection figure of the protrusions with the sipe wall faces in an expanded state, a relationship between a placement density X of the protrusions in a region that extends up to half of a sipe depth H from an opening of the sipe and a placement density Y of the protrusions in a region that extends up to half of the sipe depth H from a bottom of the sipe is X>Y.
    Type: Application
    Filed: June 21, 2011
    Publication date: December 29, 2011
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventor: Masaaki Nagayasu
  • Publication number: 20110277896
    Abstract: A plurality of sipes extending in a tire width direction are provided in a tread surface of a block. In the sipes, protrusions are formed on a first sipe wall surface of mutually opposing sipe wall surfaces and recesses that engage with the protrusions are formed on a second sipe wall surface. Collapse of portions of the block sandwiched by the sipes is suppressed due to engagement of the protrusions and the recesses. A height of protrusions positioned on an upper portion in the depth direction of the sipes is greater than a height of protrusions positioned on a lower portion.
    Type: Application
    Filed: May 11, 2011
    Publication date: November 17, 2011
    Applicant: THE YOKOHAMA RUBBER CO., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: D678175
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: March 19, 2013
    Assignee: The Yokohama Rubber Co., Ltd.
    Inventors: Masaaki Nagayasu, Yoshimasa Hashimoto, Hiroshi Furusawa, Kenichiro Endo, Kenichi Sato
  • Patent number: D682774
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: May 21, 2013
    Assignee: The Yokohama Rubber Co., Ltd.
    Inventors: Masaaki Nagayasu, Yoshimasa Hashimoto, Hiroshi Furusawa, Kenichiro Endo, Kenichi Sato