Patents by Inventor Takahiro Sajima
Takahiro Sajima 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).
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Publication number: 20180169481Abstract: A golf ball 2 includes a core 4 and a cover 6. A difference (FB2?FC2) between a secondary natural frequency FB2 of the golf ball 2 and a secondary natural frequency FC2 of the core 4 is greater than 420 Hz and not greater than 760 Hz. Preferably, a sum (FB2+FC2) is not greater than 5200 Hz. Preferably, the FC2 is not less than 1700 Hz and not greater than 2400 Hz. Preferably, the FB2 is not less than 2250 Hz and not greater than 3050 Hz. Preferably, an amount of compressive deformation Dc of the core 4 is 2.30 to 3.90 mm. Preferably, an amount of compressive deformation Db of the golf ball 2 is 1.80 to 3.30 mm. Preferably, a thickness Tc of the cover 6 is 1.00 to 2.30 mm. Preferably, a Shore D hardness Hc of the cover 6 is 54 to 67.Type: ApplicationFiled: October 16, 2017Publication date: June 21, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Takahiro SAJIMA, Hironori TAKIHARA
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Publication number: 20180169480Abstract: A golf ball 2 includes a core 4, a mid layer 6, a cover 8, and dimples 10. A Shore C hardness Hmc of the mid layer 6 is greater than a Shore C hardness Hs at a surface of the core 4. A Shore D hardness He of the cover 8 is less than a Shore D hardness Hm of the mid layer 6. Peak values and orders of maximum peaks of data constellations of the golf ball 2 are calculated. A minimum value of the peak values is not less than 95 mm. A minimum value of the orders is not less than 27, and a maximum value of the orders is not greater than 37. An average of the orders is not less than 30 and not greater than 34.Type: ApplicationFiled: October 17, 2017Publication date: June 21, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Hidetaka INOUE, Kazuya KAMINO, Takahiro SAJIMA, Kohei MIMURA
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Publication number: 20180169482Abstract: A golf ball includes a core and a cover. A difference (FB2?FC2) between a secondary natural frequency FB2 of the golf ball and a secondary natural frequency FC2 of the core is not less than 80 Hz and not greater than 420 Hz. The golf ball having a sum (FB2+FC2) of not less than 4000 Hz is preferable. Preferably, the FC2 is not less than 1800 Hz and not greater than 2500 Hz. Preferably, the FB2 is not less than 2000 Hz and not greater than 2800 Hz. Preferably, an amount of compressive deformation Dc is 2.30 mm to 3.90 mm. Preferably, an amount of compressive deformation Db is 1.80 mm to 3.30 mm. Preferably, a thickness Tc is 0.80 mm to 2.10 mm. Preferably, a Shore D hardness Hc is not less than 52 and not greater than 65.Type: ApplicationFiled: November 15, 2017Publication date: June 21, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Takahiro SAJIMA, Hironori TAKIHARA
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Publication number: 20180161634Abstract: A golf ball 2 includes a core 4, a mid layer 6 positioned outside this core, and a cover 8 positioned outside this mid layer. When a total thickness of the mid layer 6 and the cover 8 is denoted by L (mm), a Shore C hardness at a point A away from a surface of the core 4 toward a central point of the core 4 by 5L (mm) is denoted by Ha, a Shore C hardness at a point B away from the surface of the core 4 toward the central point of the core 4 by 2.5L (mm) is denoted by Hb, and a Shore C hardness at the central point of the core 4 and Shore C hardnesses of the mid layer 6 and the cover 8 are denoted by H0, Hm, and Hc, respectively; the golf ball 2 satisfies Hc?Hb>0, Hm?H0>0, and Ha?Hm>0.Type: ApplicationFiled: October 10, 2017Publication date: June 14, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Hironori TAKIHARA, Takahiro SAJIMA
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Publication number: 20180161629Abstract: A golf ball 2 has a large number of dimples 10 on a surface thereof. Fifteen axes are assumed for a phantom sphere of the golf ball 2. 30240 points on a predetermined region of the surface of the golf ball 2 during backspin about each axis are determined. A length L1 of a perpendicular line that extends from each point to the axis is calculated. A total length L2 is calculated by summing 21 lengths L1 calculated based on 21 perpendicular lines arranged in a direction of the axis. A transformed data constellation is obtained by performing Fourier transformation on a data constellation of 1440 total lengths L2 calculated along a direction of rotation about the axis. A peak value and an order of a maximum peak of the transformed data constellation are calculated. A minimum value of 15 peak values is not less than 95 mm.Type: ApplicationFiled: September 28, 2017Publication date: June 14, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Kohei MIMURA, Takahiro SAJIMA
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Publication number: 20180161632Abstract: A golf ball includes a core, one or more mid layers, a cover, and dimples. A central hardness Ho and a surface hardness Hs of the core, a hardness Hm(min) of a layer having a lowest hardness among the mid layers, and a hardness Hc of the cover satisfy the following mathematical formulas (i) to (iv).Type: ApplicationFiled: September 25, 2017Publication date: June 14, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Hironori TAKIHARA, Takahiro SAJIMA, Kohei MIMURA
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Publication number: 20180140904Abstract: An object of the present invention is to provide a golf ball traveling a great distance on driver shots.Type: ApplicationFiled: January 18, 2018Publication date: May 24, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Kohei MIMURA, Takahiro SAJIMA, Kosuke TACHIBANA
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Patent number: 9975004Abstract: A golf ball 2 includes a large number of dimples 10 on a surface thereof. The surface has a northern hemisphere N and a southern hemisphere S. Each of the hemispheres has a high-latitude region 14, a mid-latitude region 18 and a low-latitude region 16. The high-latitude region 14 has a latitude range of 40° or greater but 90° or less. The mid-latitude region 18 has a latitude range of 20° or greater but less than 40°. The low-latitude region 16 has a latitude range of 0° or greater but less than 20°. The number of planes that can divide a dimple pattern of the hemisphere so that divided dimple patterns are mirror symmetry to each other is one. Neither a dimple pattern of the high-latitude region 14 nor a dimple pattern of the low-latitude region 16 is rotationally symmetrical.Type: GrantFiled: June 26, 2015Date of Patent: May 22, 2018Assignee: DUNLOP SPORTS CO. LTD.Inventors: Takahiro Sajima, Kohei Mimura
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Patent number: 9914021Abstract: An object of the present invention is to provide a golf ball traveling a great distance on driver shots.Type: GrantFiled: April 19, 2016Date of Patent: March 13, 2018Assignee: DUNLOP SPORTS CO. LTD.Inventors: Kohei Mimura, Takahiro Sajima, Kosuke Tachibana
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Publication number: 20180056136Abstract: A golf ball 2 has a plurality of dimples 12 and a land 14 on a surface thereof. The golf ball 2 further has a large number of minute projections 18 formed on surfaces of the dimples 12 and the land 14. An average depth Fav of the dimples 12 and an average height Hav of the minute projections 18 satisfy the following mathematical formula (1). Hav<Fav*0.05??(1) An average value Pav of pitches P between the minute projections 18 and other minute projections 18 adjacent to the minute projections 18 is not less than 10 ?m and not greater than 2000 ?m.Type: ApplicationFiled: July 14, 2017Publication date: March 1, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Kohei MIMURA, Takahiro SAJIMA
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Publication number: 20180056138Abstract: A golf ball has a plurality of dimples 12 and a land 14 on a surface thereof. The golf ball further has a large number of minute projections 18 formed on surfaces of the dimples 12 and the land 14. An average pitch Pav of these minute projections 18 is less than 100 ?m. An average height Hav of these minute projections 18 is not less than 0.5 ?m and not greater than 50 ?m. The golf ball satisfies the following mathematical formula. Lav<3*Tav In the mathematical formula, Lav represents an average value of distances L between the minute projections 18 and other minute projections 18 adjacent to the minute projections 18, and Tav represents an average value of widths T of these minute projections 18.Type: ApplicationFiled: July 28, 2017Publication date: March 1, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Takahiro SAJIMA, Kohei MIMURA
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Publication number: 20180028873Abstract: A golf ball 2 includes a core 4, one or more mid layers 6, a cover 8, and dimples 10. A central hardness Ho and a surface hardness Hs of the core 4, a hardness Hm(min) of a layer having a lowest hardness among the mid layers 6, and a hardness Hc of the cover 8 satisfy the following mathematical formulas (1) to (4). Hs?Ho>15??(1) Hc?Hm(min)>20??(2) ?10<Hm(min)?Ho<15??(3) 5<Hc?Hs<20??(4) An occupation ratio So and a ratio Rs of a number of the dimples 10 each having a diameter of from 9.60% to 10.37% of a diameter of the golf ball 2, relative to a total number of the dimples 10, satisfy the following mathematical formula (5). Rs??2.Type: ApplicationFiled: June 15, 2017Publication date: February 1, 2018Applicant: DUNLOP SPORTS CO. LTD.Inventors: Hironori TAKIHARA, Takahiro SAJIMA, Kohei MIMURA
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Patent number: 9861861Abstract: A golf ball 2 includes a core 4, a mid layer 6, a cover 8 and a paint layer 10. The core 4 includes a center 12 and an envelope layer 14. The golf ball 2 satisfies the following mathematical formulas. In the mathematical formulas, Tm represents a thickness of the mid layer, Tcmin represents a minimum thickness of the cover, Tcmax represents a maximum thickness of the cover, and Tp represents a thickness of the paint layer. The golf ball 2 has a large number of dimples 16 on a surface thereof. The number of planes that can divide a pattern of the dimples so that divided patterns are mirror symmetry to each other is one. Tm>Tcmax?Tcmin>Tp (Tcmax?Tcmin)?0.15 mm 0.15?(Tp/Tcmin)?0.Type: GrantFiled: June 26, 2015Date of Patent: January 9, 2018Assignee: DUNLOP SPORTS CO. LTD.Inventors: Kazuya Kamino, Kosuke Tachibana, Takahiro Sajima
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Patent number: 9849340Abstract: A golf ball 2 has a large number of dimples 10 on a surface thereof. The contours of the dimples 10 are non-circular. A standard deviation of areas of the dimples 10 is equal to or less than 1.7 mm2. A ratio of a total area of the dimples 10 relative to a surface area of a phantom sphere of the golf ball 2 is equal to or greater than 80%. By comparting lines CS obtained by projecting sides of a regular dodecahedron, which is inscribed in the phantom sphere, onto the phantom sphere, a surface of the phantom sphere can be divided into 12 units Ut each of which meets the following mathematical formula (I): ?2?(Nt/12)?Nu?2??(I), where Nt represents the total number of the dimples 10 and Nu represents the number of the dimples 10 on one unit.Type: GrantFiled: September 17, 2015Date of Patent: December 26, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventors: Kohei Mimura, Takahiro Sajima, Hyoungchol Kim
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Patent number: 9849342Abstract: A golf ball of one aspect of the present invention includes a spherical core, one or more cover members to cover the core, and a coating layer to coat a cover member configuring an outermost layer of the one or more cover members. A plurality of dimples is formed in the cover member. Shore-D hardness of the cover member is equal to or larger than 50. A 10% modulus of the coating layer is equal to or smaller than 160 kgf/cm2. Roughness is produced on a surface of the coating layer after applying a coating material over the cover member of the outermost layer A maximum height Rz of the coating layer is equal to or larger than 3 ?m.Type: GrantFiled: October 8, 2015Date of Patent: December 26, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventor: Takahiro Sajima
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Patent number: 9839812Abstract: A golf ball of one aspect of the present invention includes a spherical core, one or more cover members to cover the core, and a coating layer to coat a cover member configuring an outermost layer of the one or more cover members. A plurality of dimples is formed in the cover member of the outermost layer. Roughness is produced on a surface of the coating layer after applying a coat over the cover member of the outermost layer. An average value Fa (mm) of maximum depths of the plurality of dimples and arithmetic average roughness Ra (?m) on the surface of the coating layer, satisfy a relational expression: ?1.5×Fa+0.8?Ra??1.5×Fa+1.8.Type: GrantFiled: October 8, 2015Date of Patent: December 12, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventor: Takahiro Sajima
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Patent number: 9789369Abstract: An object of the present invention is to provide a golf ball traveling a great distance on driver shots and on iron shots.Type: GrantFiled: April 26, 2016Date of Patent: October 17, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventors: Hironori Takihara, Kosuke Tachibana, Takahiro Sajima, Kohei Mimura
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Patent number: 9750982Abstract: A golf ball has a large number of dimples 10 on a surface thereof. The dimples 10 include a plurality of small dimples 10S each having an area of less than 8.0 mm2, and a plurality of large dimples 10L each having an area of equal to or greater than 8.0 mm2. A ratio PS of a sum of areas of all the small dimples 10S to a surface area of a phantom sphere of the golf ball is less than 2.0%. A ratio PL of a sum of areas of all the large dimples 10L to the surface area of the phantom sphere is equal to or greater than 79.0%. A degree G of uniformity of areas of the large dimples 10L is equal to or less than 1.15.Type: GrantFiled: November 5, 2015Date of Patent: September 5, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventors: Kohei Mimura, Takahiro Sajima, Hironori Takihara
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Patent number: 9713747Abstract: A golf ball has a large number of dimples on a surface thereof. The golf ball meets the following mathematical formula (I): Su?9.0*So?6.04??(I), Where: So represents a ratio of a sum of spherical surface areas of all the dimples to a surface area of a phantom sphere of the golf ball; and Su represents a standard deviation (mm2) of the spherical surface areas of all the dimples. Preferably, the ratio So is equal to or greater than 0.780. Preferably, the standard deviation Su is equal to or less than 2.150 mm2. Preferably, a number of the dimples is equal to or greater than 300 but equal to or less than 390. Preferably, an average Sa of the spherical surface areas s of all the dimples is equal to or greater than 14.00 mm2.Type: GrantFiled: July 28, 2014Date of Patent: July 25, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventors: Takahiro Sajima, Hyoungchol Kim
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Patent number: 9707452Abstract: A golf ball has a large number of dimples 10 on a surface thereof. The dimples 10 include a plurality of small dimples 10S each having an area of less than 8.0 mm2, and a plurality of large dimples 10L each having an area of equal to or greater than 8.0 mm2. A ratio PS of a sum of areas of all the small dimples 10S to a surface area of a phantom sphere of the golf ball is less than 2.0%. The number NL of the large dimples 10L is equal to or greater than 250 but less than 450. The number NL of the large dimples 10L and a degree G of uniformity of areas of the large dimples 10L satisfy the following mathematical formula (II): G<0.0032·NL+0.26??(II).Type: GrantFiled: October 21, 2015Date of Patent: July 18, 2017Assignee: DUNLOP SPORTS CO. LTD.Inventors: Kohei Mimura, Takahiro Sajima