Sri Sports Limited

Sumitomo Rubber Industries Limited

Tomoya Hirano

Masahiko Ueda

Yasushi Sugimoto

Naoyoshi Ueda

Shimpei Oyama

Masahide Onuki

Takashi Nakamura

Hiroshi Abe

Seiji Hayase

Kenji Kii

Satoru Hanamitsu

Yuki Nagano

A golf club set includes a plurality of golf clubshaving different loft angles. The golf clubsinclude at least one 1st golf clubA having a loft angle of less than 34 degrees, and at least one 2nd golf clubB having a loft angle of not less than 34 degrees. Each of the at least one 1st golf clubA and the at least one 2nd golf clubB comprises a clubfaceprovided with a plurality of face grooveshaving a depth. The depth of the face groovesof the at least one 2nd golf clubB is larger than the depth of the face groovesof the at least one 1st golf clubA.

Golf club set

A golf club set includes at least one first golf club whose loft angle is not less than 46 degrees and less than 56 degrees, and at least one second golf club whose loft angle is not less than 56 degrees and less than 60 degrees. The first and second golf clubs each comprise a face provided with score lines each formed by a groove having a groove bottom and a pair of opposite grooves walls which are inclined at an inclination angle with respect to a normal direction to the face so that the groove width between the opposite grooves walls is increased from the groove bottom toward the face. The inclination angle of the groove walls of the score lines of the first golf club is in the range from 28 to 42 degrees. The inclination angle of the groove walls of the score lines of the second golf club is in the range from 23 to 37 degrees and smaller than that of the first golf club.

A golf club headcomprises: a porous part Ps including a porous metal and integrally formed; and a non-porous part NPs. The porous part Ps constitutes at least a part of a sole. The porous part Ps has a whole thickness part Pt occupying a whole thickness of the sole. Preferably, a rate Ra of an area occupied by the whole thickness part Pt among an area of the sole is equal to or greater than 15%. Preferably, the porous part Ps and the non-porous part NPs are welded mutually. In the disposal of the porous part Ps in the head, preferably, a substituted head obtained by substituting the porous part Ps with the same material as that of the non-porous part NPs adjacent to the porous part Ps is considered.

Golf club head

A golf club head has a hollow structure comprising a head main body provided with a opening and a cover covering the opening. The head main body is made of a metal material and provided in the opening with a supporting part for supporting a peripheral edge part of the cover fitted in the opening. The cover is made of a low specific gravity material. A method for producing the golf club head comprises a step of preparing a first workpiece having an opening, which step comprises forming the supporting part through a press working of a sheet metal having a uniform thickness.

Method for producing golf club head

A golf club head comprises: a hollow structure having an insertion-opening in the outer surface of the golf club head; a quick-release lid of the insertion-opening; a tubular part disposed in a hollow of the hollow structure and having a bottomed hole with which the insertion-opening communicates; and a gravity point adjuster. The gravity point adjuster comprises: a heavy-weight member having a specific gravity and a length L; a light-weight member having a specific gravity less than that of the heavy-weight member and a length Lmore than the length L; and an elastic member having a specific gravity less than that of the heavy-weight member, and an elastic modulus lower than those of the heavy-weight member and light-weight member. The heavy-weight member, light-weight member and elastic member are inserted in the bottomed hole by the use of the insertion-opening so that their relative positions relative to the bottomed hole can be changed easily by the golfer himself or herself.

A golf club head comprises has an inner surface including a back surface of the face portion that is provided with a crown-side thick-walled rib and a sole-side thick-walled rib. The crown-side thick-walled rib includes an upper face rib disposed in the face portion and extending from the central thick-walled part to a peripheral edge of the back surface of the face portion on a crown portion side, and a crown rib disposed in the crown portion and extending backwardly of the head from the upper face rib. The sole-side thick-walled rib includes a lower face rib disposed in the face portion and extending from the central thick-walled part to a peripheral edge of the back surface of the face portion on a sole portion side, and a sole rib disposed in the sole portion and extending backwardly of the head from the lower face rib.

A golf club head having a club face for hitting a ball comprises a hollow main body provided with a front opening, and a face member disposed at the front of the main body so that a front surface thereof forms at least a major part of the club face, and a rear surface thereof faces a hollow of the main body. The peripheral edge of the face member is welded to the main body so as to form a weld bead, and the width of the weld bead is changed so that a difference (Wmax&#x2212;Wmin) between the maximum width Wmax and minimum width Wmin is not less than 1 mm.

Golf club head and method for manufacturing the same

A hollow golf club head is disclosed, wherein a front member including a face portion and a hosel portion of the club head is made of a material having a specific gravity &#x3c1;; a rear member forming a backmost point of the club head is made of a material having a specific gravity &#x3c1;; and an intermediate member extending annularly through in a crown portion, a sole portion and a sidewall portion of the head is made of a material having a specific gravity &#x3c1;; and the specific gravity &#x3c1;is more than the specific gravity &#x3c1;which is more than the specific gravity &#x3c1;

An iron-type golf club headhaving excellent durability and weight distribution design and comprising a metallic head bodyA having a facefor hitting a golf ball and a recess portion, and a metallic weight memberB having a larger specific gravity than the head bodyA, the memberB being fitted to and welded to the recess portion to form a part of the outer surface of the head bodyA, wherein at least one closed spacesurrounded by the weight memberB and the surface of the recess portionis formed inside the head body.

Iron-type golf club head

A method for manufacturing a golf club head having a hollow structure composed of a main body-member and a metal face member welded thereto, comprises the steps of: (a) preparing a rolled material having a constant thickness; (b) cutting out a face member part or blank from the rolled material; (c) making the face member by forming the turnback through press working on the face member part; and (d) reducing the thickness of a corresponding-to-turnback region by machining prior to the step (c), wherein the corresponding-to-turnback region is a region of the cutout face member part corresponding to the turnback, or a region of the rolled material corresponding to the turnback.

A method for manufacturing a golf club head composed of a metal main body and a non-flat metal face member which are welded each other is disclosed. In order to make the non-flat metal face member, an in-process face material is cut out from a rolled metal plate having a constant thickness. And a turnback is formed around the in-process face material by press working. Before making the press working, the region of the in-process face material corresponding to the turnback is decreased in the thickness by a cutting work.

Method for manufacturing golf club head

A golf club head comprises a face portion of which front face defines a club face, wherein at least a part of the face portion is formed by a unidirectionally rolled plate of a titanium alloy having alpha phase such as alpha titanium alloys and alpha+beta titanium alloys, and the unidirectional rolled direction of the plate is oriented in the toe-heel direction of the head. At least 50% in area of the face portion is formed by the unidirectionally rolled plate. The angle (theta) between the rolled direction and the toe-heel direction is not more than 15 degrees.

A golf club head is provided with a face portion comprising: a central thick part having a thickness Tc; a crown-side thick part having a thicknesses Tr; a sole-side thick part having a thicknesses Tr; a toe-side thinner part having a thickness TT; and a heel-side thinner part having a thickness TH, wherein: (1) Tc&#x3e;=Tr&#x3e;TT and (2) Tr&#x3e;TH are satisfied; and the centroid of the central thick part is positioned on the toe-side of an extension of a widthwise center line of the crown-side thick part towards the sole and further positioned on the heel-side of an extension of a widthwise center line of the sole-side thick part towards the crown.

A wood-type golf club head has a hollow structure having a specific configuration in which, in order to make it easier to rotate the club head around the clubshaft during swing while maintaining a large lateral moment of inertia, the relative positions of the club face, the center of gravity, the clubshaft center line and the heel are optimized by limiting the face progression within a range between 21 to 27 mm, and the area ratio (S/S) of two specific right-angle triangles (OGP and ORQ) described on a horizontal plane (HP) within a range of from 4 to 10.

Wood-type golf club head

A method for manufacturing a hollow golf club head is disclosed, wherein a metallic main frame provided with a top opening and a bottom opening, a metallic crown plate and a metallic sole plate are prepared. The sole plate is placed in the bottom opening. A die is inserted into the inside of the main frame through the top opening. A protrusion of the sole plate is crushed onto the edge portion of the main frame around the bottom opening, by the use of the inserted die. Then the top opening is closed by the crown plate. The specific gravity SGm and proof stress YSm of the main frame, the specific gravity SGs and proof stress YSs of the sole plate, and the specific gravity SGf of the face plate satisfy: SGf=&#x3c;SGm&#x3c;SGs and YSs&#x3c;YSm.

Growing community of inventors

Kobe, Japan

Tomoya Hirano