Patents by Inventor Daijiro KOJIMA

Daijiro KOJIMA 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: 11839795
    Abstract: An object of the present disclosure is to provide a golf ball having excellent durability and flight distance and good shot feeling for an average golfer who hits a golf ball at a slow head speed. The present disclosure provides a golf ball comprising a spherical core and at least two cover layers covering the spherical core, wherein a difference between a core surface crosslinking density and a core center crosslinking density is more than 1.0×102 mol/m3 and less than 9.0×102 mol/m3, a hardness difference between a core surface hardness Cs (Shore C hardness) and a core center hardness Co (Shore C hardness) is 13.0 or more and 30.0 or less, a compression deformation amount of the core when applying a load from an initial load of 98 N to a final load of 1275 N to the core is less than 3.
    Type: Grant
    Filed: September 20, 2022
    Date of Patent: December 12, 2023
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventors: Takahiro Sajima, Daijiro Kojima, Hikaru Nagakura
  • Patent number: 11833396
    Abstract: An object of the present disclosure is to provide a golf ball having excellent durability and flight distance and good shot feeling for an average golfer who hits a golf ball at a slow head speed. The present disclosure provides a golf ball comprising a spherical core and at least two cover layers covering the spherical core, wherein a difference between a core surface crosslinking density and a core center crosslinking density is more than 1.0×102 mol/m3 and less than 9.0×102 mol/m3, a hardness difference between a core surface hardness Cs (Shore C hardness) and a core center hardness Co (Shore C hardness) is 13.0 or more and 30.0 or less, a compression deformation amount of the core when applying a load from an initial load of 98 N to a final load of 1275 N to the core is 3.
    Type: Grant
    Filed: September 20, 2022
    Date of Patent: December 5, 2023
    Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
    Inventors: Daijiro Kojima, Takahiro Sajima, Hikaru Nagakura
  • Publication number: 20230241459
    Abstract: A golf ball can have a large number of dimples on a surface thereof. A trajectory of the golf ball can be calculated under conditions of an initial speed of 260 ft/s, a launch angle of 15.0 degrees, and an initial backspin rate of 3000 rpm satisfying the following mathematical formula, Amax ? 4 .0 ? * ? Vave + 13 .10, wherein Amax represents a maximum value (degree) of a vector angle A in the trajectory, and Vave represents an average volume (mm3) of the dimples. The vector angle A can be calculated by the mathematical formula A = ATAN Vy / Vx , wherein Vx represents a horizontal component of a speed of the golf ball, and Vy represents a vertical component of the speed of the golf ball.
    Type: Application
    Filed: January 31, 2023
    Publication date: August 3, 2023
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventors: Takahiro SAJIMA, Daijiro KOJIMA
  • Publication number: 20230241460
    Abstract: A golf ball can have a relatively large number of dimples on a surface thereof. A trajectory of the golf ball calculated under conditions of an initial speed of 260 ft/s, a launch angle of 15.0 degrees, and an initial backspin rate of 3000 rpm can satisfy the following mathematical formula: Amin??5.0*Vave?38.98, wherein A min represents a minimum value (degree) of a vector angle A in the trajectory, and Vave represents an average volume (mm3) of the dimples. The vector angle A can be calculated by the following mathematical formula: A=ATAN(Vy/Vx), wherein Vx represents a horizontal component of a speed of the golf ball, and Vy represents a vertical component of the speed of the golf ball.
    Type: Application
    Filed: January 31, 2023
    Publication date: August 3, 2023
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventors: Daijiro KOJIMA, Takahiro SAJIMA
  • Publication number: 20230103376
    Abstract: An object of the present disclosure is to provide a golf ball having excellent durability and flight distance and good shot feeling for an average golfer who hits a golf ball at a slow head speed. The present disclosure provides a golf ball comprising a spherical core and at least two cover layers covering the spherical core, wherein a difference between a core surface crosslinking density and a core center crosslinking density is more than 1.0×102 mol/m3 and less than 9.0×102 mol/m3, a hardness difference between a core surface hardness Cs (Shore C hardness) and a core center hardness Co (Shore C hardness) is 13.0 or more and 30.0 or less, a compression deformation amount of the core when applying a load from an initial load of 98 N to a final load of 1275 N to the core is less than 3.
    Type: Application
    Filed: September 20, 2022
    Publication date: April 6, 2023
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventors: Takahiro SAJIMA, Daijiro KOJIMA, Hikaru NAGAKURA
  • Publication number: 20230089974
    Abstract: An object of the present disclosure is to provide a golf ball having excellent durability and flight distance and good shot feeling for an average golfer who hits a golf ball at a slow head speed. The present disclosure provides a golf ball comprising a spherical core and at least two cover layers covering the spherical core, wherein a difference between a core surface crosslinking density and a core center crosslinking density is more than 1.0×102 mol/m3 and less than 9.0×102 mol/m3, a hardness difference between a core surface hardness Cs (Shore C hardness) and a core center hardness Co (Shore C hardness) is 13.0 or more and 30.0 or less, a compression deformation amount of the core when applying a load from an initial load of 98 N to a final load of 1275 N to the core is 3.
    Type: Application
    Filed: September 20, 2022
    Publication date: March 23, 2023
    Applicant: Sumitomo Rubber Industries, Ltd.
    Inventors: Daijiro KOJIMA, Takahiro SAJIMA, Hikaru NAGAKURA