Patent application number | Description | Published |
20080220901 | Golf ball - The invention provides a golf ball composed of a core, a cover, and an intermediate layer between the core and the cover, which ball has a surface with a plurality of non-circular dimples thereon. The cover is harder than the intermediate layer. The ball surface has land areas with intervals therebetween of from 0.05 to 1.0 mm, the lands having outer surfaces that define an outermost peripheral face of the ball. The non-circular dimples have non-circular inside corners that are curved. The ball satisfies conditions (I) to (IV) below: | 09-11-2008 |
20090098950 | MOLD FOR FORMING GOLF BALL - There are provided a golf ball molding die capable of manufacturing a golf ball having a satisfactory surface condition, and a golf ball manufactured by using the die. The present golf ball molding die comprises at least two die bodies within which a cavity for molding a golf ball is formed by jointing of the die bodies; and a pin accommodating hole provided in at least one of the die bodies, and is characterized in that at least one groove communicating directly with the cavity is provided in the wall surface of the pin accommodating hole. | 04-16-2009 |
20090111613 | GOLF BALL - An object of the present invention is to provide a golf ball having an improved aesthetic appearance and enhanced flying performance. The present invention provides a golf ball on which a plurality of dimples are arranged on the spherical surface thereof, wherein each of the dimples has at least two contour main parts and contour connecting parts, and the at least two contour main parts are connected to each other by the contour connecting parts, and the contour connecting parts are formed so as to be curved toward the inside of the contour main parts from the outermost points. | 04-30-2009 |
20090160088 | GOLF BALL AND DIE FOR MOLDING THE SAME - There are provided a golf ball in which the depths of dimples after grinding, which greatly affect the trajectory of golf ball, can be controlled readily and exactly, and a golf ball molding die for manufacturing the golf ball. The golf ball molding die in accordance with the present invention comprises two die bodies in which a cavity for molding a golf ball is formed by joining the die bodies to each other; and a protrusion formed on the cavity side surface of at least one of the die bodies, the protrusion having a uniform height from the surface or an imaginary spherical surface on which the protrusion is assumed to be absent toward the center of the cavity, wherein when a parting line is at latitude zero degree, the protrusion is arranged in the range of from latitude about 10 degrees to latitude about 80 degrees. | 06-25-2009 |
20100093468 | GOLF BALL - A golf ball has an increased surface occupancy ratio of dimples, the dimples are shallow to restrain a lift acting on the golf ball flying in a high-speed region after the ball has been hit, and the lift of the golf ball flying in a low-speed region in the latter half of the trajectory is maintained for a long time, by which a longer carry can be obtained. The golf ball has plural dimples formed on the surface thereof, in which at least about 10 percent of dimples of all the dimples on the surface are noncircular dimples in which a boundary line between a land part and the dimple include a curved line part and a straight line part, and the noncircular dimples each have a flat bottom surface. | 04-15-2010 |
20100151966 | GOLF BALL AND METHOD OF MANUFACTURING THE SAME - There are provided a golf ball molding die capable of manufacturing a golf ball having a satisfactory surface condition, and a golf ball manufactured by using the die. The present golf ball molding die comprises at least two die bodies within which a cavity for molding a golf ball is formed by jointing of the die bodies; and a pin accommodating hole provided in at least one of the die bodies, and is characterized in that at least one groove communicating directly with the cavity is provided in the wall surface of the pin accommodating hole. | 06-17-2010 |
20100179000 | GOLF BALL MOLD AND GOLF BALL - The invention provides a golf ball mold composed of a plurality of mold parts which removably mate to form a hollow interior spherical cavity having a cavity wall with a plurality of dimple-forming protrusions thereon and which have a parting surface that is formed in a convex shape and a concave shape matching the convex shape. All or some of the dimple-forming protrusions are formed at positions at least about 0.03 mm away from an outside edge of a convex portion of the parting surface. The mold eliminates the possibility that molding flash projecting out from the parting surface of the mold will enter the dimples, as a result of which the dimples are not affected by the trimming of flash. Golf balls manufactured with such a mold are able to effectively manifest the aerodynamic performance of dimples tightly and uniformly arranged on the surface of the ball. | 07-15-2010 |
20100190581 | GOLF BALL - The invention provides a golf ball with a surface having a plurality of dimples formed thereon. The number of dimples is at least 250 and not more than 400, the dimples have a surface coverage (SR) of at least 70% and a volume ratio (VR) of at least 1.1%, are of at least three types and have an average depth of at least about 0.18 mm and a diameter (DM) to depth (DP) ratio (DM/DP) of not more than about 22. The (total number of Db)/(total number of Da) ratio, where Da represents dimples having a diameter of at least 3.7 mm and Db represents dimples having a diameter of less than 3.7 mm, is at least about 0.005 and not more than about 1. The ball has a coefficient of lift CL at a Reynolds number of 70,000 and a spin rate of 2,000 rpm which is maintained at 60% or more of the coefficient of lift CL at a Reynolds number of 80,000 and a spin rate of 2,000 rpm. The golf ball of the invention lowers fluctuations in lift and drag at high and low spin rates, enabling a stable trajectory to be achieved. | 07-29-2010 |
20100216575 | GOLF BALL AND METHOD FOR DESIGNING SAME - A golf ball includes noncircular dimples having smooth bottom surfaces; a method for designing the golf ball is disclosed. A noncircular dimple D | 08-26-2010 |
20100273583 | GOLF BALL AND DIE FOR MOLDING THE SAME - There are provided a golf ball in which the depths of dimples after grinding, which greatly affect the trajectory of golf ball, can be controlled readily and exactly, and a golf ball molding die for manufacturing the golf ball. The golf ball molding die in accordance with the present invention comprises two die bodies in which a cavity for molding a golf ball is formed by joining the die bodies to each other; and a protrusion formed on the cavity side surface of at least one of the die bodies, the protrusion having a uniform height from the surface or an imaginary spherical surface on which the protrusion is assumed to be absent toward the center of the cavity, wherein when a parting line is at latitude zero degree, the protrusion is arranged in the range of from latitude about 10 degrees to latitude about 80 degrees. | 10-28-2010 |
20100298070 | TWO-PIECE SOLID GOLF BALL - The invention provides a two-piece solid golf ball having a core and a cover, which ball has a plurality of dimples formed on the surface. The number of dimples is from 250 to 500, the dimples have a surface coverage (SR) of at least 70% and a volume ratio (VR) of at least 1.0%, and dimples of at least three types are used. In addition, the dimples have an average depth of at least about 0.18 mm and a diameter-to-depth ratio (DM/DP) of not more than about 23. The ball has a coefficient of lift CL at a Reynolds number of 70,000 and a spin ratio of 2,000 rpm which is maintained at 60% or more of the coefficient of lift CL at a Reynolds number of 80,000 and a spin rate of 2,000. This two-piece solid golf ball lowers fluctuations in lift and drag at high and low spin rates, enabling a stable trajectory to be achieved. | 11-25-2010 |
20100316756 | MOLD FOR FORMING GOLF BALL AND GOLF BALL MANUFACTURED USING THE SAME - There are provided a mold for forming a golf ball, which allows a dimple formed near the equator of golf ball corresponding to the partition surface of upper and lower molds to be formed so as to have the same shape as that of a dimple formed in other regions, and a golf ball manufactured using this mold. The mold for forming a golf ball in accordance with the present invention includes at least two body parts, a cavity is formed within the mold by the joining of the at least two body parts, and in at least one of the body parts, a groove for forming a projecting land part which is ground after the formation of the golf ball is provided in a cavity wall surface adjacent to the whole circumference of a parting line formed by the joining. | 12-16-2010 |
20100317464 | GOLF BALL AND METHOD FOR MANUFACTURING THE SAME - A method for manufacturing a golf ball includes the steps of forming the golf ball by using a mold, which mold includes at least two body parts, and is configured so that a cavity is formed within the mold by the joining of the at least two body parts, and in at least one of the body parts, a groove for forming a projecting land part which is ground after the formation of the golf ball is provided in a cavity wall surface near the entire circumference of a parting line formed by the joining; and performing treatment in which the golf ball formed by using the mold is treated so that the color of the entire land part of the golf ball is different from the color of dimples. | 12-16-2010 |
20110028245 | GOLF BALL - A golf ball has uniform gaps between dimples even if the surface occupancy ratio of the dimples is high, and therefore the aerodynamic performance thereof is improved, whereby a longer flight distance can be obtained. In the golf ball having a plurality of dimples and land parts surrounded by the plurality of dimples, the land part has a shape having at least one vertex, the land part is connected to at least two adjacent land parts substantially by a point, and the area of the land part is in the range of about 0.05 mm | 02-03-2011 |
20110040535 | GOLF BALL TRAJECTORY SIMULATION METHOD - The invention is directed at a golf ball trajectory simulation method that employs arithmetic operations executed by a computer to analyze a trajectory of a golf ball having a plurality of dimples on a surface thereof when the ball is launched into flight. The trajectory of the ball is estimated by setting up a golf ball model within a virtual airflow space (field) where a grid has been generated; setting a weight for the golf ball model and applying initial conditions (initial velocity, launch angle, spin rate) to the ball model so as to cause the model to fly within the virtual airflow space (field); calculating a lift coefficient and a drag coefficient for the golf ball from an air stream velocity, direction and pressure calculated in each grid cell; and calculating a flight distance and left-to-right dispersion for the golf ball from launch until landing by calculating a change in height, a change in lateral direction, a change in velocity and a change in spin rate for the golf ball during flight. | 02-17-2011 |
20110106500 | METHOD FOR DESIGNING GOLF BALL AND GOLF BALL MANUFACTURED BY THE SAME - A method for manufacturing a golf ball includes the step of designing plural dimples on a surface of the golf ball so as to satisfy the following parameters. A total number N of the dimples is approximately 400 or less; a surface roughness Rda of the golf ball is approximately 0.085 mm or less; and a value obtained by dividing an average convex part surface area Srt in the first cross-section and the second cross-section by an average concave part cross-section Sru in the first cross-section and the second cross-section is approximately 0.9 or less. The golf ball surface roughness Rda is the average value of a first golf ball cross-section surface roughness Rp, a second golf ball surface roughness Rm, and a third golf ball surface roughness Rs. The average convex part surface area Srt is the average value of a first convex part surface area Art that, in the first cross-section, is surrounded by the reference spherical surface and the golf ball surface that is higher than the reference spherical surface and a second convex part surface area Art that, in the second cross-section, is surrounded by the reference spherical surface and the golf ball surface that is higher than the reference spherical surface. | 05-05-2011 |
20110159988 | MOLD FOR FORMING GOLF BALL, METHOD TO MANUFACTURE GOLF BALL WITH SAME, AND GOLF BALL MANUFACTURED USING THE SAME - A golf ball that, in the process of spherical grinding after forming, can maintain the dimple shape and achieve the designed dimple surface occupation ratio. A mold for forming a golf ball of the present invention has at least two body parts, a cavity being formed within the mold by the joining of the at least two body parts, the body part comprising a cavity wall surface which has a spherical surface shape with the center thereof being at the center of the cavity and dimple-forming protrusions provided on the cavity wall surface, the dimple-forming protrusions being connected to the cavity wall surface at an angle of about 60 or more degrees in a region from about 3 μm to about 20 μm from the cavity wall surface. | 06-30-2011 |
20110159989 | GOLF BALL MOLD, GOLF BALL AND METHOD OF MANUFACTURING A GOLF BALL - The invention provides a golf ball mold that is composed of a plurality of mold parts which removably mate to form a cavity having an inner wall with a plurality of dimple-forming protrusions thereon, wherein a non-circular resin injection port is formed between a plurality of mutually adjoining dimple-forming protrusions which include dimple-forming protrusions that lie across a parting line of the mold. Also provided is a golf ball molded using such a mold, and a golf ball manufacturing method which uses such a mold. | 06-30-2011 |
20110250987 | MULTI-PIECE SOLID GOLF BALL - The invention provides a multi-piece solid golf ball having a solid core, an inner cover layer and an outer cover layer, which outer cover layer has a plurality of dimples on a surface thereof. The value obtained by subtracting a material hardness (Shore D) of the outer cover layer from a material hardness (Shore D) of the inner cover layer is greater than −5 and less than +5. The dimples number at least 250 and not more than 500, have a surface coverage (SR) of at least 70% and a volume ratio (VR) of at least 1.0%, are of at least three types of mutually differing dimple diameter (DM) and/or dimple depth (DP), and have an average depth of at least about 0.18 mm and a diameter-to-depth ratio (DM/DP) of not more than about 23. The ball has a coefficient of lift CL at a Reynolds number of 70,000 and a spin rate of 2,000 rpm which is maintained at 60% or more of the coefficient of lift CL at a Reynolds number of 80,000 and a spin rate of 2,000. This multi-piece solid golf ball is able to substantially reduce the distance traveled by the ball when struck at a high HS, while at the same time holding down the reduction in distance when struck at a low HS. | 10-13-2011 |
20110250988 | MULTI-PIECE SOLID GOLF BALL - The invention provides a multi-piece solid golf ball having a solid core, an inner cover layer and an outer cover layer, which outer cover layer has a plurality of dimples on a surface thereof. The inner cover layer has a thickness of from 0.8 to 3.0 mm and a material hardness (Shore D) of from 10 to 60, the outer cover layer has a thickness of from 0.7 to 3.0 mm and a material hardness (Shore D) of from 45 to 62, and the material hardness (Shore D) of the outer cover layer is higher than the material hardness (Shore D) of the inner cover layer. The dimples number at least 250 and not more than 500, have a surface coverage (SR) of at least 70% and a volume ratio (VR) of at least 1.0%, are of at least three types of mutually differing dimple diameter (DM) and/or dimple depth (DP), and have an average depth of at least about 0.18 mm and a diameter-to-depth ratio (DM/DP) of not more than about 23. The ball has a coefficient of lift CL at a Reynolds number of 70,000 and a spin rate of 2,000 rpm which is maintained at 60% or more of the coefficient of lift CL at a Reynolds number of 80,000 and a spin rate of 2,000. This multi-piece solid golf ball is able to substantially reduce the distance traveled by the ball when struck at a high HS, while at the same time holding down the reduction in distance when struck at a low HS. | 10-13-2011 |
20110250989 | MULTI-PIECE SOLID GOLF BALL - The invention provides a multi-piece solid golf ball having a solid core, an inner cover layer and an outer cover layer, which outer cover layer has a plurality of dimples on a surface thereof. The inner cover layer has a thickness of from 0.8 to 3.0 mm and a material hardness (Shore D) of from 50 to 80, the outer cover layer has a material hardness (Shore D) of from 35 to 60, and the material hardness (Shore D) of the inner cover layer is higher than the material hardness (Shore D) of the outer cover layer. The dimples number at least 250 and not more than 500, have a surface coverage (SR) of at least 70% and a volume ratio (VR) of at least 1.0%, are of at least three types of mutually differing dimple diameter (DM) and/or dimple depth (DP), and have an average depth of at least about 0.18 mm and a diameter-to-depth ratio (DM/DP) of not more than about 23. The ball has a coefficient of lift CL at a Reynolds number of 70,000 and a spin rate of 2,000 rpm which is maintained at 60% or more of the coefficient of lift CL at a Reynolds number of 80,000 and a spin rate of 2,000. This multi-piece solid golf ball is able to substantially reduce the distance traveled by the ball when struck at a high HS, while at the same time holding down the reduction in distance when struck at a low HS. | 10-13-2011 |
20110257945 | GOLF BALL TRAJECTORY SIMULATION METHOD - The invention is directed at a golf ball trajectory simulation method which sets up a golf ball model within a virtual airflow space where a grid has been generated, sets a weight for the ball model and applies initial conditions (initial velocity, launch angle, spin rate) to the ball model so as to cause the model to fly within the virtual airflow space, then calculates the lift coefficient and the drag coefficient for the golf ball from the air stream velocity, direction and pressure calculated in each grid cell, and calculates the flight distance and left-to-right dispersion for the golf ball from launch until landing by calculating the change in height, change in lateral direction, change in velocity and change in spin rate for the golf ball during flight. The trajectory simulation method divides the flight path of the golf ball model into two or three regions based on the criteria that Re=250,000 to 170,000 is a high-velocity region, Re=170,000 to 100,000 is a medium-velocity region and Re=100,000 and below is a low-velocity region, and sets up a height for the grid adjacent to the golf ball model surface in the high-velocity region (grid height A), a height for the grid adjacent to the golf ball model surface in the medium-velocity region (grid height B) and a height for the grid adjacent to the golf ball model surface in the low-velocity region (grid height B) such that grid height A10-20-2011 | |
20110287862 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples have a volume ratio (VR) of at least 1.0 but less than 1.6%. The ball has a deflection, when compressed under a final load of 1,275 N (130 kgf) from an initial load state of 98 N (10 kgf), of from 4.0 to 6.0 mm, an initial velocity, as measured using an initial velocity measuring apparatus of the same type as a USGA drum rotation-type initial velocity instrument, which is greater than 77.7 m/s but not more than 82 m/s, and a ratio of total distance traveled when struck at a head speed of 54 m/s to total distance traveled when struck at a head speed of 35 m/s (HS54/HS35) of from 1.30 to 1.50. This golf ball is able to achieve a superior distance when struck at a low head speed and on shots with an iron. | 11-24-2011 |
20110287863 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples have a volume ratio (VR) of from 1.0 to 1.4%. The ball has an initial velocity, as measured using an initial velocity measuring apparatus of the same type as a USGA drum rotation-type initial velocity instrument, of from 75.5 to 77.7 m/s, and a ratio of total distance traveled when struck at a head speed of 54 m/s to total distance traveled when struck at a head speed of 35 m/s (HS54/HS35) of from 1.30 to 1.50. This golf ball is able to substantially reduce the distance traveled by the ball when struck at a high head speed, while at the same time holding down the decrease in distance when struck at a low head speed. | 11-24-2011 |
20110287864 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples number at least 250 but not more than 500, and have a volume ratio (VR) of from 1.20 to 1.60%. The outermost cover layer has a surface hardness, expressed as the Shore D hardness, of from 58 to 75. The ball has a deflection, when compressed under a final load of 1,275 N (130 kgf) from an initial load state of 98 N (10 kgf), of from 4.0 to 6.0 mm. This golf ball is able to substantially reduce the distance traveled by the ball when struck at a high head speed, while at the same time holding down the decrease in distance when struck at a low head speed. | 11-24-2011 |
20110287867 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples have a volume ratio (VR) of at least 1.6%. The ball has an initial velocity, as measured using an initial velocity measuring apparatus of the same type as a USGA drum rotation-type initial velocity instrument, which is at least 77 m/s, and has a ratio of total distance traveled when struck at a head speed of 54 m/s to total distance traveled when struck at a head speed of 35 m/s (HS54/HS35) of from 1.30 to 1.50. This golf ball is able to substantially reduce the distance traveled by the ball when struck at a high head speed, while at the same time holding down the decrease in distance when struck at a low head speed. | 11-24-2011 |
20110287868 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples number at least 250 but not more than 500, and have a volume ratio (VR) of from 1.20 to 1.50%. The ball has a deflection, when compressed under a final load of 1,275 N (130 kgf) from an initial load state of 98 N (10 kgf), of from 4.0 to 6.0 mm. This golf ball is able to substantially reduce the distance traveled by the ball when struck at a high head speed, while at the same time holding down the decrease in distance when struck at a low head speed. | 11-24-2011 |
20110287869 | GOLF BALL - The invention provides a golf ball having a solid core, a cover of at least one layer, and a plurality of dimples on a surface of an outermost layer of the cover. The dimples number at least 250 but not more than 500, and have a volume ratio (VR) of from 1.00 to 1.40%. The ball has a deflection, when compressed under a final load of 1,275 N (130 kgf) from an initial load state of 98 N (10 kgf), of from 4.0 to 6.0 mm, and has an initial velocity, as measured using an initial velocity measuring apparatus of the same type as a USGA drum rotation-type initial velocity instrument, of from 70.0 to 76.0 m/s. This golf ball is able to substantially reduce the distance traveled by the ball when struck at a high head speed, while at the same time holding down the decrease in distance when struck at a low head speed. | 11-24-2011 |
20110300971 | GOLF BALL - A golf ball includes a land part representing a symbol, and dimples defining the land part by outer edges thereof and disposed on a surface of the golf ball. The symbol represented by the land part may include numerals, letters, pictures, or logo. The dimples defining the land part by outer edges thereof can include at least two non-circular dimples. The dimples defining the land part by outer edges thereof can include a dimple having a wall surface having a linear shape extending substantially in a depth direction, the wall surfaces being adjacent to the land part representing the symbol. | 12-08-2011 |
20110300972 | GOLF BALL - A golf ball has plural dimples provided on a surface of the golf ball; a first land part existing between the plural dimples and having as its surface a spherical surface of a sphere having the center of the golf ball as its center; a second land part having a boundary with the first land part or boundaries with the first land part and the plural dimples and having a surface having a smaller curvature than the spherical surface of the first land part; and an engraved marking disposed substantially on the second land part. | 12-08-2011 |
20120010026 | GOLF BALL - A golf ball includes a plurality of circular dimples formed on the surface thereof, each of the circular dimples having a flat bottom surface; and a plurality of noncircular dimples formed on the surface of the golf ball, at least about 10 percent of dimples of all the dimples on the surface being the noncircular dimples, wherein a boundary line between a land part of the golf ball and the noncircular dimples each comprise a curved line part and a straight line part. The plurality of noncircular dimples each having a flat bottom surface. The bottom surface of the noncircular dimple may has a planar shape approximately similar to the boundary line. The lift coefficient CL at Re 70000/2000 rpm may be at least about 70 percent of the lift coefficient CL at Re 80000/2000 rpm, and the drag coefficient CD at Re 180000/2520 rpm is up to about 0.225. | 01-12-2012 |
20120065949 | GOLF BALL ESTIMATE SIMULATION METHOD - When an air stream is made to flow into a virtual airflow space set up by computer and the velocity, direction and pressure of the air stream flowing around a rotating golf ball model are calculated for each cell of a grid, by setting an airflow stabilization time during which computation proceeds without rotation of the golf ball model until the air stream that flows into the virtual airflow space ceases to be influenced by the initial air stream and stabilizes, then rotating the golf ball model at a given spin rate once the airflow stabilization time has elapsed and calculating the velocity, direction and pressure of the air stream for each grid cell, the computational time can be greatly shortened without lowering accuracy, enabling coefficients of lift and coefficients of drag to be easily calculated from the velocity, direction and pressure of the air stream for each grid cell. | 03-15-2012 |
20120072184 | GOLF BALL AND METHOD FOR DESIGNING SAME - A golf ball includes noncircular dimples having smooth bottom surfaces; a method for designing the golf ball is disclosed. A noncircular dimple D | 03-22-2012 |
20120322584 | METHOD FOR ARRANGING DIMPLES ON GOLF BALL SURFACE - A method for arranging dimples on a golf ball surface includes: determining an initial arrangement of dimples; dividing the surface of a golf ball into multiple equivalent unit regions; based on a dimple interval between two freely selected dimples within one of the unit regions, determining whether or not the two dimples are in an adjacent relationship to each other; and changing the positions of the two dimples corresponding to the dimple interval between the two freely selected dimples in the adjacent relationship, wherein determining of the adjacent relationship and changing of the position are repeated until the maximum interval, which is a maximum value of the dimple interval between two freely selected dimples in the adjacent relationship in the unit region, falls below a predetermined value. | 12-20-2012 |
20120329578 | MOLD FOR FORMING GOLF BALL AND GOLF BALL MANUFACTURED USING THE SAME - There are provided a mold for forming a golf ball, which allows a dimple formed near the equator of golf ball corresponding to the partition surface of upper and lower molds to be formed so as to have the same shape as that of a dimple formed in other regions, and a golf ball manufactured using this mold. The mold for forming a golf ball in accordance with the present invention includes at least two body parts, a cavity is formed within the mold by the joining of the at least two body parts, and in at least one of the body parts, a groove for forming a projecting land part which is ground after the formation of the golf ball is provided in a cavity wall surface adjacent to the whole circumference of a parting line formed by the joining. | 12-27-2012 |
20130256948 | GOLF BALL MOLD AND GOLF BALL MANUFACTURING METHOD - A golf ball mold that includes a mold body configured as a plurality of mold parts which have at least a parting surface that defines a parting line at a golf ball equator and removably mate to form a cavity having an inner wall with a plurality of dimple-forming protrusions thereon is provided. The golf ball mold includes a support pin which has an end face with a plurality of dimple-forming protrusions thereon and is extendable into and retractable from the cavity. The support pin extends into the cavity to support a center sphere and, when in a retracted state, the end face thereof defines a portion of the inner wall of the cavity. The end face of the support pin includes a pole of the cavity and has a peripheral edge which intersects a parallel of latitude at 10 degrees from the pole. | 10-03-2013 |
20140073455 | GOLF BALL - The invention provides a golf ball endowed with an improved distance and durability. The ball has a core and a cover, the core being formed of a rubber composition containing a base rubber, a co-crosslinking agent, a crosslinking initiator and a metal oxide. The co-crosslinking agent is methacrylic acid. The core has a hardness profile in which, letting (A) be the JIS-C hardness at the core surface, (B) be the JIS-C hardness at a position 2 mm in from the surface toward the center of the core, (C) be the JIS-C hardness at a position 5 mm in from the surface toward the center of the core, (D) be the JIS-C hardness at a position 10 mm in from the surface toward the center of the core, (E) be the JIS-C hardness at a position 15 mm in from the surface toward the center of the core, and (F) be the JIS-C hardness at the center of the core, (A) to (F) have specific hardnesses. | 03-13-2014 |
20140073460 | GOLF BALL - The invention provides a golf ball endowed with an improved distance and durability. The ball has a core and a cover, the core being formed of a rubber composition containing a base rubber, a co-crosslinking agent, a crosslinking initiator and a metal oxide. The base rubber is a mixture of (A) polybutadiene with (B) styrene-butadiene rubber and/or isoprene rubber, the co-crosslinking agent is methacrylic acid, and the metal oxide is zinc oxide. The rubber composition contains the crosslinking initiator in an amount of from 1.2 to 5 parts by weight per 100 parts by weight of the base rubber. | 03-13-2014 |
20140367884 | METHOD FOR FORMING GOLF BALL AND MOLD THEREFOR - A method for forming a golf ball provides a core member comprising a core of a golf ball into a cavity of a mold so that the core member is supported by a movable holding pin disposed in the mold; forming a layer outside the core member by injecting a material of the layer into the cavity; and retracting the pin from the cavity into the mold during the material injection so that a portion projecting from a surface of the layer is formed by a tip of the pin, the projecting portion having a site area of at least 0.2% in relation to an entire area of the tip of the pin and having a height of at least 0.2 mm. This method can be implemented by controlling the retraction of the pin, or alternatively by using the pin having a predetermined indentation portion on the tip. | 12-18-2014 |