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: 11524527
    Abstract: A tire includes a tread, sidewalls, beads, and pairs of first and second grooves formed in the tread. A first land is between the first grooves, and second lands are between one of the first and second grooves and between another of the first and second main grooves. First sipes and lateral grooves are in the first land, at the same angle, the first sipes being connected to the lateral grooves. The first sipe and the lateral groove open to one of the first grooves. Second sipes and auxiliary grooves are in a bent shape in the second land. The first and second sipes are oriented the same. The auxiliary groove includes first and second portions. An intersection angle of the first portion with the second sipe is within 45° to 90°. A length a of the first portion and a length b of the second portion satisfy 0.05×a?b?0.4×a.
    Type: Grant
    Filed: August 23, 2018
    Date of Patent: December 13, 2022
    Assignee: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: 11364750
    Abstract: A pneumatic tire is provided. In a meridian cross-section, an external contour shape of the bead core is a polygon formed by common tangent lines of a plurality of circumferential portions of a bead wire, the external contour shape includes a single vertex located toward the outside in a tire radial direction, an internal angle formed by two sides sandwiching the vertex is an acute angle, a bottom side of the external contour shape is inclined with respect to the tire lateral direction by from 2° to 9°, and the carcass layer is bent and folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from a position of an outer end of the bead core in the tire radial direction extends toward a sidewall portion in contact with a body portion.
    Type: Grant
    Filed: November 19, 2018
    Date of Patent: June 21, 2022
    Assignee: The Yokohama Rubber Co., LTD.
    Inventors: Ryohei Takemori, Masaaki Nagayasu, Yuki Sasaya, Atsushi Tanno, Hiraku Kouda, Jun Matsuda
  • Patent number: 11331960
    Abstract: Of layers configuring a bead core of a pneumatic tire, the width W0 of one of the layers including the greatest number of rows, the width W1, W2 of other of the layers located respectively innermost and outermost in the radial direction satisfy W1>W2 and W2?0.5×W0. The position of width W0 is inward in the radial direction of the center of the bead core. A carcass is folded and curved along the bead core and extends toward sidewalls where a folded back portion of the carcass contacts a body of the carcass. A rubber occupancy ratio in a closed region formed by the body and the folded back portion is 0.1% to 15%. The cross-sectional area S2 and hardness H2 of a filler outward of the carcass in the lateral direction, and the cross-sectional area S1 and the hardness H1 of the side reinforcing layer satisfy 0.12?(S2×H2)/(S1×H1)?0.50.
    Type: Grant
    Filed: December 4, 2018
    Date of Patent: May 17, 2022
    Assignee: The Yokohama Rubber Co., LTD.
    Inventors: Atsushi Tanno, Hiraku Kouda, Jun Matsuda, Masaaki Nagayasu, Yuki Sasaya, Ryohei Takemori
  • Patent number: 11260702
    Abstract: In a cross-section of a pneumatic tire, a contour of the bead core is a polygon formed by tangent lines of circumferential portions of a bead wire, the contour includes a vertex with an acute angle and a bottom side opposite the vertex, the carcass layer is folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from an outer end of the bead core extends in the radial direction, and a distance in the radial direction between a center of an arc profile of a tire outer surface and a straight line extending in the lateral direction through the vertex is within 20% of a radius r of the arc, and a distance in the lateral direction between the center of the arc and a straight line extending in the radial direction through the vertex is within 2r±0.4r.
    Type: Grant
    Filed: November 19, 2018
    Date of Patent: March 1, 2022
    Inventors: Yuki Sasaya, Masaaki Nagayasu, Ryohei Takemori, Atsushi Tanno, Hiraku Kouda, Jun Matsuda
  • Publication number: 20210394561
    Abstract: In a pneumatic tire, a tread portion including rows of land portions defined by circumferential grooves extending in a tire circumferential direction is formed by sectors divided in the tire circumferential direction, sipes extending in a tire width direction formed in the land portions include a three-dimensional sipe, whose shape tread surface changes along a sipe depth direction, and a two-dimensional sipe, whose shape is constant along the sipe depth direction, and a ratio R1 of a number of the three-dimensional sipes with respect to a total number of the sipes in a first boundary region, which is within 15 mm on one side of a sector dividing position in the tire circumferential direction, and a ratio Rt of a number of the three-dimensional sipes with respect to a total number of the sipes in all of the tread portion satisfy relationship R1<Rt.
    Type: Application
    Filed: October 10, 2019
    Publication date: December 23, 2021
    Inventor: Masaaki NAGAYASU
  • Publication number: 20210323356
    Abstract: A pneumatic tire includes a tread portion molded by sectors divided in a tire circumferential direction. The pneumatic tire includes circumferential grooves, rows of land portions, and sipes. The circumferential grooves extend in the tire circumferential direction in the tread portion. The rows of land portions are defined by the circumferential grooves. The sipes extend in a tire width direction in at least one row of the rows of land portions. The sipes include at least one shallow bottom sipe and regular sipes. The at least one shallow bottom sipe is disposed in a boundary region including a dividing position of each of the sectors. The regular sipes are disposed at positions more separated from the dividing position of each of the sectors than the at least one shallow bottom sipe. The at least one shallow bottom sipe is shallower than the regular sipes.
    Type: Application
    Filed: August 22, 2019
    Publication date: October 21, 2021
    Inventor: Masaaki NAGAYASU
  • Publication number: 20210268846
    Abstract: A pneumatic tire includes protrusion portions projecting from and extending along a tire side portion, the protrusion portions being disposed on an outer side in a tire radial direction in an placement region that is a region from a position of 15% to a position of 85% of a tire cross-sectional height from a reference position on an inner side in the tire radial direction of the tire cross-sectional height, and including a first extending portion extending along the tire side portion in a single arc shape or a single straight shape, the first extending portion having a length within a range of no less than 1.0 and no more 6.0 times a height in the tire radial direction of the placement region, and the tire side portion having a thickness at a tire maximum width position within from 2 mm to 9 mm.
    Type: Application
    Filed: June 20, 2019
    Publication date: September 2, 2021
    Inventors: Yuki Sasaya, Masaaki Nagayasu, Ryohei Takemori, Hiraku Kouda
  • Publication number: 20210268845
    Abstract: A pneumatic tire includes protrusion portions formed on, extending along, and projecting from at least one tire side portion, the protrusion portions including at least one bend portion at a position where a direction in which the protrusion portion extends changes, and also including extending portions defined by the bend portion. Where the extending portion disposed on an outermost side in the radial direction among the extending portions is taken to be a first extending portion, a highest extending portion that is the extending portion in which an average extending portion height that is an average height from the tire side portion of each extending portion is highest is any one of the extending portions other than the first extending portion. The tire side portion has a thickness at a tire maximum width position within a range of no less than 2 mm and no more than 9 mm.
    Type: Application
    Filed: April 17, 2019
    Publication date: September 2, 2021
    Inventors: Masaaki Nagayasu, Hiraku Kouda, Ryohei Takemori, Yuki Sasaya
  • Publication number: 20210268844
    Abstract: A pneumatic tire includes protrusion portions formed on at least one tire side portion of tire side portions located on both sides in a width direction, projecting from a tire side surface that is a surface of the tire side portion, and extending along the tire side surface, the protrusion portions having an angle ? within a range of no less than 6% and no more than 50% of an angle of one round in a circumferential direction, the angle ? being relative and in the circumferential direction between two protrusion portion end position lines that respectively extend in a radial direction through different end portions of both end portions in an extending direction of the protrusion portions, and the tire side portion having a thickness at a tire maximum width position within a range of no less than 2 mm and no more than 9 mm.
    Type: Application
    Filed: June 3, 2019
    Publication date: September 2, 2021
    Inventors: Hiraku Koda, Masaaki Nagayasu, Ryohei Takemori, Yuki Sasaya
  • Publication number: 20210260935
    Abstract: A pneumatic tire includes protrusion portions formed on a side portion of tire side portions located on both sides in a width direction, projecting from a side surface of the side portion, and extending along the side surface, the protrusion portions including a bend portion where a direction in which the protrusion portions extend changes, and also including extending portions defined by the bend portion, a width of the extending portions changing at a position straddling the bend portion, a first extending portion having the longest length among the extending portions having a maximum width of no less than 1.0 mm and no more than 3.0 mm, and a thickness of the side portion at a maximum tire width position being no less than 2 mm and no more than 9 mm.
    Type: Application
    Filed: April 17, 2019
    Publication date: August 26, 2021
    Inventors: Ryohei Takemori, Hiraku Kouda, Masaaki Nagayasu, Yuki Sasaya
  • Publication number: 20210206207
    Abstract: A tire includes a tread, sidewalls, beads, and pairs of first and second grooves formed in the tread. A first land is between the first grooves, and second lands are between one of the first and second grooves and between another of the first and second main grooves. First sipes and lateral grooves are in the first land, at the same angle, the first sipes being connected to the lateral grooves. The first sipe and the lateral groove open to one of the first grooves. Second sipes and auxiliary grooves are in a bent shape in the second land. The first and second sipes are oriented the same. The auxiliary groove includes first and second portions. An intersection angle of the first portion with the second sipe is within 45° to 90°. A length a of the first portion and a length b of the second portion satisfy 0.05×a?b?0.4×a.
    Type: Application
    Filed: August 23, 2018
    Publication date: July 8, 2021
    Inventor: Masaaki Nagayasu
  • Patent number: 11040580
    Abstract: In a pneumatic tire including a side reinforcing layer, the maximum width W0 of a bead core and the widths W1, W2 of the bead core at innermost and outermost sides in the radial direction, respectively, satisfy W1>W2 and W2?0.5×W0. W0 is toward the inside of the center of the bead core in the radial direction. A carcass is folded and curved along the bead core, and a folded back portion of the carcass extends toward the sidewalls while contacting a body of the carcass. A rubber occupancy ratio in a region formed by the body and the folded back portion of the carcass is 0.1% to 15%. The cross-sectional area S2 of a filler toward the outside of the carcass in the lateral direction, the hardness H2 of the filler, the cross-sectional area S1 of a side reinforcing layer and the hardness H1 of the side reinforcing layer satisfy 0.15?(S2×H2)/(S1×H1)?0.60.
    Type: Grant
    Filed: December 4, 2018
    Date of Patent: June 22, 2021
    Inventors: Hiraku Kouda, Jun Matsuda, Atsushi Tanno, Masaaki Nagayasu, Ryohei Takemori, Yuki Sasaya
  • Publication number: 20210170806
    Abstract: In a cross-section of a pneumatic tire, a contour of the bead core is a polygon formed by tangent lines of circumferential portions of a bead wire, the contour includes a vertex with an acute angle and a bottom side opposite the vertex, the carcass layer is folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from an outer end of the bead core extends in the radial direction, and a distance in the radial direction between a center of an arc profile of a tire outer surface and a straight line extending in the lateral direction through the vertex is within 20% of a radius r of the arc, and a distance in the lateral direction between the center of the arc and a straight line extending in the radial direction through the vertex is within 2r±0.4r.
    Type: Application
    Filed: November 19, 2018
    Publication date: June 10, 2021
    Inventors: Yuki Sasaya, Masaaki Nagayasu, Ryohei Takemori, Atsushi Tanno, Hiraku Kouda, Jun Matsuda
  • Publication number: 20210170807
    Abstract: A pneumatic tire is provided. In a meridian cross-section, an external contour shape of the bead core is a polygon formed by common tangent lines of a plurality of circumferential portions of a bead wire, the external contour shape includes a single vertex located toward the outside in a tire radial direction, an internal angle formed by two sides sandwiching the vertex is an acute angle, a bottom side of the external contour shape is inclined with respect to the tire lateral direction by from 2° to 9°, and the carcass layer is bent and folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from a position of an outer end of the bead core in the tire radial direction extends toward a sidewall portion in contact with a body portion.
    Type: Application
    Filed: November 19, 2018
    Publication date: June 10, 2021
    Inventors: Ryohei Takemori, Masaaki Nagayasu, Yuki Sasaya, Atsushi Tanno, Hiraku Kouda, Jun Matsuda
  • Publication number: 20200376903
    Abstract: In a pneumatic tire including a side reinforcing layer, the maximum width W0of a bead core and the widths W1, W2 of the bead core at innermost and outermost sides in the radial direction, respectively, satisfy W1>W2 and W2?0.5×W0. W0 is toward the inside of the center of the bead core in the radial direction. A carcass is folded and curved along the bead core, and a folded back portion of the carcass extends toward the sidewalls while contacting a body of the carcass. A rubber occupancy ratio in a region formed by the body and the folded back portion of the carcass is 0.1% to 15%. The cross-sectional area S2 of a filler toward the outside of the carcass in the lateral direction, the hardness H2 of the filler, the cross-sectional area S1of a side reinforcing layer and the hardness H1 of the side reinforcing layer satisfy 0.15?(S2×H2)/(S1×H1)?0.60.
    Type: Application
    Filed: December 4, 2018
    Publication date: December 3, 2020
    Inventors: Hiraku Kouda, Jun Matsuda, Atsushi Tanno, Masaaki Nagayasu, Ryohei Takemori, Yuki Sasaya
  • Publication number: 20200376904
    Abstract: Of layers configuring a bead core of a pneumatic tire, the width W0 of one of the layers including the greatest number of rows, the width W1, W2 of other of the layers located respectively innermost and outermost in the radial direction satisfy W1>W2 and W2?0.5×W0. The position of width W0 is inward in the radial direction of the center of the bead core. A carcass is folded and curved along the bead core and extends toward sidewalls where a folded back portion of the carcass contacts a body of the carcass. A rubber occupancy ratio in a closed region formed by the body and the folded back portion is 0.1% to 15%. The cross-sectional area S2 and hardness H2 of a filler outward of the carcass in the lateral direction, and the cross-sectional area S1 and the hardness H1 of the side reinforcing layer satisfy 0.12?(S2×H2)/(S1×H1)?0.50.
    Type: Application
    Filed: December 4, 2018
    Publication date: December 3, 2020
    Inventors: Atsushi Tanno, Hiraku Kouda, Jun Matsuda, Masaaki Nagayasu, Yuki Sasaya, Ryohei Takemori
  • Patent number: 9827812
    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: Grant
    Filed: June 3, 2013
    Date of Patent: November 28, 2017
    Assignee: The Yokohama Rubber Co., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: 9539863
    Abstract: In a pneumatic tire, a single block includes a first sipe and a second sipe each extending in a tire width direction and disposed at a predetermined pitch in a tire circumferential direction. The first sipe and the second sipe include a first sipe portion that has a linear form when the block is viewed planarly, and a second sipe portion that has a zigzag shape when the block is viewed planarly and that connects to the first sipe portion. The first sipe portion includes a pair of sipe wall faces that face each other and have a linear form when viewed as a cross-section from a direction perpendicular to a sipe length direction, and includes a protrusion disposed on a first face of the sipe wall faces and a recess disposed on a second face of the sipe wall faces so as to mate with the protrusion.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: January 10, 2017
    Assignee: The Yokohama Rubber Co., LTD.
    Inventors: Hiroshi Furusawa, Masaaki Nagayasu
  • Patent number: 9381775
    Abstract: A pneumatic tire having improved performance on ice and wet road surfaces without degradation of steering stability on dry road surfaces. The pneumatic tire includes a tread portion, side wall portions, bead portions, a plurality of circumferential grooves extending in the tire circumferential direction and a plurality of lateral grooves extending in the tire width direction provided in the tread portion, a plurality of blocks partitioned by the circumferential and lateral grooves, and a plurality of sipes extending in the tire width direction in each block. At least some sipes include a main body part located centrally in the block width direction, and a deep-bottomed communicating portion that communicates with the circumferential groove adjacent to the block and has a depth not less than 50% the depth of the circumferential groove, and mutually mating convex and concave portions are formed locally in opposing surfaces in the deep-bottomed communicating portion.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: July 5, 2016
    Assignee: THE YOKOHAMA RUBBER CO., LTD.
    Inventor: Masaaki Nagayasu
  • Patent number: D788686
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: June 6, 2017
    Assignee: THE YOKOHAMA RUBBER CO., LTD.
    Inventors: Masaaki Nagayasu, Yoshimasa Hashimoto, Hiroshi Furusawa, Kenichirou Endou, Kenichi Sato