# US 10,765,921 B2 · Iron golf club head > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,765,921 B2 - Document ID: US10765921B2 - Status: Granted - Kind: B2 - Application number: 16/375,637 - Filed: 2019-04-04 - Published: 2019-08-01 - Granted: 2020-09-08 - Earliest claimed: 2017-07-13 - Assignees: Sumitomo Rubber Industries, Ltd. - Applicants: Sumitomo Rubber Industries, Ltd. - Inventors: Takahiro Norimura; Kazuhiro Hayashi - Web page: https://patentgrep.com/patent/US10765921B2 ## CPC - A63B 53/047: {iron-type} - A63B 53/0475: {with one or more enclosed cavities} - A63B 53/042: {the face insert consisting of a material different from that of the head} - A63B 53/0445: {Details of grooves or the like on the impact surface} - A63B 60/02: Ballast means for adjusting the centre of mass (A63B60/24, A63B60/54 take precedence) - A63B 60/54: with means for damping vibrations - A63B 2053/0491: {with added weights, e.g. changeable, replaceable} - A63B 2102/32: Golf - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract An iron golf club head comprises; a head main body including a club face provided with score lines; a weight member having a specific gravity larger than that of the head main body; and a fixing member having a specific gravity larger than that of the head main body and less than that of the weight member, and fixed to the head main body by welding so as to cover the weight member. In a forward tilting state of the club head in which the score lines are horizontal and the club face is vertical, the distance D in the perpendicular direction to the club face from the backmost position of the club head to the center of gravity of the weight member is not more than 47.3% of the maximum thickness W of the club head which is the shortest distance from the backmost position of the club head to the club face. ## Claims ### Claim 1 An iron-type golf club head comprising: a head main body including a striking face comprising scorelines, the main body comprising a main body specific gravity; a weight member having a weight member specific gravity that is larger than the main body specific gravity; and a fixing member having a fixing member specific gravity less than the weight member specific gravity, the fixing member being fixed to the head main body by welding so as to cover the weight member, wherein: the weight member further comprises a weight member center of gravity; and measured in a direction perpendicular to the striking face, the club head further comprises: a backmost location; a maximum thickness w being the shortest distance between the striking face and the backmost location; and a distance D, from the backmost location to the weight member center of gravity, that is not more than 47.3% of the maximum thickness w of the club head. ### Claim 2 (depends on 1) The iron-type golf club head according to claim 1, wherein the distance D is not more than 40.0% of the maximum thickness w of the club head. ### Claim 3 (depends on 1) The iron-type golf club head according to claim 1, wherein the weight member is completely covered with the fixing member and the fixing member forms at least a part of a back face of the head main body. ### Claim 4 (depends on 1) The iron-type golf club head according to claim 1, wherein the weight member is disposed in a recess of the head main body. ### Claim 5 (depends on 4) The iron-type golf club head according to claim 4, wherein the recess is positioned in a sole of the club head forming a bottom face of the club head. ### Claim 6 (depends on 4) The iron-type golf club head according to claim 4, wherein the recess comprises a pair of slant faces that taper toward a bottom surface of the recess, and the weight member contacts the slant faces but does not contact the bottom surface so as to form a gap therebetween. ### Claim 7 (depends on 1) The iron-type golf club head according to claim 1, wherein: the scorelines comprise a toe-most end and a heel-most end; and the weight member further comprises a center of gravity that is located, in the heel-to-toe direction, between the heel-most end and the toe-most end of the scorelines. ### Claim 8 (depends on 1) The iron-type golf club head according to claim 1, wherein weldability of the head main body with respect to the weight member is lower than weldability of the head main body with respect to the fixing member. ### Claim 9 An iron-type golf club head comprising: a head main body including a striking face comprising scorelines, the main body comprising a main body specific gravity; a weight member having a weight member specific gravity that is larger than the main body specific gravity; and a fixing member having a fixing member specific gravity less than the weight member specific gravity, the fixing member being fixed to the head main body by welding so as to cover the weight member, a club head center of gravity; a backmost location measured in a direction perpendicular to the striking face; a maximum thickness w being the shortest distance between the striking face and the backmost location; and a depth L of the club head center of gravity measured from and perpendicular to the striking face, the depth L being no less than 27.0% of the maximum thickness w of the club head. ### Claim 10 (depends on 9) The iron-type golf club head according to claim 9, wherein: the scorelines comprise a heel-most end and a toe-most end; and the depth L is no less than 27.5% of a thickness wt of the club head measured at a position of the toe-most end of the scorelines. ### Claim 11 (depends on 9) The iron-type golf club head of claim 9, wherein the fixing member specific gravity is larger than the main body specific gravity. ### Claim 12 (depends on 9) The iron-type golf club head of claim 9, wherein: the weight member further comprises a weight member center of gravity; and a distance D, measured from the backmost location to the weight member center of gravity in a direction perpendicular to the striking face, is not more than 47.3% of the maximum thickness w of the club head. ### Claim 13 (depends on 9) The iron-type golf club head according to claim 9, wherein the weight member is completely covered with the fixing member and the fixing member forms at least a part of a back face of the head main body. ### Claim 14 (depends on 9) The iron-type golf club head according to claim 9, wherein the weight member is disposed in a recess of the head main body. ### Claim 15 (depends on 9) The iron-type golf club head according to claim 9, wherein the recess is positioned in a sole of the club head forming a bottom face of the club head. ### Claim 16 (depends on 9) The iron-type golf club head according to claim 9, wherein the recess comprises a pair of slant faces that taper toward a bottom surface of the recess and the weight member contacts the slant faces but does not contact the bottom surface so as to form a gap therebetween. ### Claim 17 (depends on 9) The iron-type golf club head according to claim 9, wherein: the scorelines comprise a toe-most end and a heel-most end; and the weight member further comprises a center of gravity that is located, in the heel-to-toe direction, between the heel-most end and the toe-most end of the scorelines. ### Claim 18 (depends on 9) The iron-type golf club head according to claim 9, wherein weldability of the head main body with respect to the weight member is lower than weldability of the head main body with respect to the fixing member.