# US 11,998,816 B2 · Golf club head with vibrational damping system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,816 B2 - Document ID: US11998816B2 - Status: Granted - Kind: B2 - Application number: 17/653,279 - Filed: 2022-03-02 - Published: 2022-09-08 - Granted: 2024-06-04 - Earliest claimed: 2021-03-02 - Assignees: Karsten Manufacturing Corporation - Applicants: Karsten Manufacturing Corporation - Inventors: Travis D. Milleman; Matthew T. Schier; Murphy R. Alexander - Web page: https://patentgrep.com/patent/US11998816B2 ## CPC - A63B 60/54: with means for damping vibrations - A63B 53/0408: {characterised by specific dimensions, e.g. thickness} - A63B 53/0445: {Details of grooves or the like on the impact surface} - A63B 53/047: {iron-type} - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract Embodiments of an iron-type golf club head comprising a high moment of inertia and a damping system. The damping system includes an insert covering a lower portion of the back face and a badge covering an upper portion of the back face. The damping system covers a large proportion of the back face and provides a club head with desirable sound and feel characteristics. ## Claims ### Claim 1 An iron-type golf club head comprising: a strike face comprising a geometric center and a back face opposite the strike face; a heel portion; a toe portion opposite the heel portion; a top rail; a sole opposite the top rail; a rear wall extending upward from the sole at least partially towards the top rail; wherein the rear wall comprises a rear wall top edge; an insert cavity formed by at least an inner surface of the rear wall and a lower portion of the back face; wherein the insert cavity comprises an insert cavity opening extending between the rear wall top edge and the lower portion of the back face; wherein the insert cavity comprises an insert cavity base formed by an inner surface of the sole; a damping system comprising: an insert disposed within the insert cavity; a badge attached to an upper portion of the back face; wherein the insert and the badge are in contact with back face; wherein the damping system defines a damping system coverage area measured as a combined surface area of the back face contacted by the insert and the badge; wherein the damping system coverage area is greater than 3.0 in2; and wherein the damping system coverage area is greater than 85% of an available surface area of the back face. ### Claim 2 (depends on 1) The iron-type golf club head of claim 1, wherein the strike face comprises a plurality of grooves extending in a heel-to-toe direction; and wherein the club head comprises a blade length measured as a heel-to-toe distance between a heel-most extent of the plurality of grooves and a toe-most extent of the strike face. ### Claim 3 (depends on 2) The iron-type golf club head of claim 2, further comprising a ground plane tangent to the sole at an address position and a coordinate system; wherein the coordinate system comprises: an X-axis extending in a heel-to-toe direction parallel to the ground plane; a Y-axis orthogonal to the X-axis and extending in a top rail-to-sole direction; a Z-axis orthogonal to the X-axis and the Y-axis and extending in a front-to-back direction; wherein the club head further comprises an Iyy moment of inertia measured about the Y-axis; wherein the Iyy moment of inertia is greater than 390 g·in2; and wherein a ratio between the Iyy moment of inertia and the blade length is greater than 100 g·in. ### Claim 4 (depends on 1) The iron-type golf club head of claim 1, further comprising a rear cavity bounded, at least partially, by the top rail, the heel portion, the toe portion, and the rear wall; wherein the top rail forms a top rail rear edge, the heel portion forms a heel rear edge, and the toe portion forms a toe rear edge; wherein the top rail rear edge, the heel rear edge, the toe rear edge, and the rear wall top edge form a rear cavity opening; and wherein the rear cavity extends from the rear cavity opening to the upper portion of the back face. ### Claim 5 (depends on 4) The iron-type golf club head of claim 4, wherein the badge fills between 75% and 99% of a volume of the rear cavity. ### Claim 6 (depends on 1) The iron-type golf club head of claim 1, wherein the insert comprises an insert bottom surface abutting the insert cavity base and an insert top surface proximate the insert cavity opening; and wherein the insert top surface is below the geometric center of the strike face. ### Claim 7 (depends on 1) The iron-type golf club head of claim 1, wherein the badge comprises badge top edge and a badge bottom edge; and wherein a thickness of the badge increases from the badge top edge to the badge bottom edge. ### Claim 8 (depends on 7) The iron-type golf club head of claim 7, wherein the badge bottom edge entirely covers the insert cavity opening. ### Claim 9 (depends on 1) The iron-type golf club head of claim 1, wherein the badge comprises an adhesive layer coupled to the back face and a rigid layer exposed to an exterior of the club head. ### Claim 10 (depends on 9) The iron-type golf club head of claim 9, wherein the adhesive layer comprises a viscoelastic material. ### Claim 11 (depends on 1) The iron-type golf club head of claim 1, wherein the available surface area of the back face is greater than 3.0 in2. ### Claim 12 An iron-type golf club head comprising: a strike face and a back face opposite the strike face; a heel portion; a toe portion opposite the heel portion; a top rail; a sole opposite the top rail; a rear wall extending upward from the sole at least partially towards the top rail; wherein the strike face comprises a strike face perimeter and a plurality of score lines extending in a heel-to-toe direction; wherein the rear wall comprises a rear wall top edge; an insert cavity formed by at least an inner surface of the rear wall and a lower portion of the back face; wherein the insert cavity comprises an insert cavity opening extending between the rear wall top edge and the lower portion of the back face; wherein the insert cavity comprises an insert cavity base formed by an inner surface of the sole; a damping system comprising: an insert disposed within the insert cavity; a badge attached to an upper portion of the back face; wherein the insert and the badge are in contact with back face; wherein the damping system defines a damping system coverage area measured as a combined surface area of the back face contacted by the insert and the badge; wherein the damping system coverage area is greater than 3.0 in2; and wherein the strike face defines a scoring area extending from the strike face perimeter near the top rail to the strike face perimeter near the sole; wherein the scoring area comprises a scoring area heel boundary defined by a line connecting a heel-most extent of the plurality of score lines and a scoring area toe boundary defined by a line connecting a toe-most extent of the plurality of score lines; wherein the back face defines a projection corresponding to a location of the scoring area; and wherein a portion of the damping system coverage area that overlaps the projection is greater than 75% of a surface area of the scoring area. ### Claim 13 (depends on 12) The iron-type golf club head of claim 12, wherein the club head comprises a blade length measured as a heel-to-toe distance between a heel-most extent of the plurality of score lines and a toe-most extent of the strike face. ### Claim 14 (depends on 12) The iron-type golf club head of claim 12, wherein the badge comprises an adhesive layer in contact with the upper portion of the back face, a rigid layer opposite the adhesive layer and exposed to a rear exterior of the club head, and a filler layer disposed between the adhesive layer and the rigid layer. ### Claim 15 (depends on 14) The iron-type golf club head of claim 14, wherein the rigid layer of the badge comprises a hardness greater than 80 HRB. ### Claim 16 (depends on 12) The iron-type golf club head of claim 12, wherein the plurality of score lines comprise a spacing distance less than 0.12 inch. ### Claim 17 An iron-type golf club head comprising: a strike face and a back face opposite the strike face; a heel portion; a toe portion opposite the heel portion; a top rail; a sole opposite the top rail; a rear wall extending upward from the sole at least partially towards the top rail; wherein the rear wall comprises a rear wall top edge; an insert cavity formed by at least an inner surface of the rear wall and a lower portion of the back face; wherein the insert cavity comprises an insert cavity opening extending between the rear wall top edge and the lower portion of the back face; wherein the insert cavity comprises an insert cavity base formed by an inner surface of the sole; a damping system comprising: an insert disposed within the insert cavity; a badge attached to an upper portion of the back face; wherein the insert and the badge are in contact with back face; wherein the damping system defines a damping system coverage area measured as a combined surface area of the back face contacted by the insert and the badge; wherein the damping system coverage area is greater than 3.0 in2; and wherein the damping system coverage area is between 60% and 85% of a total surface area of the strike face. ### Claim 18 (depends on 17) The iron-type golf club head of claim 17, wherein the top rail comprises a top rail thickness, measured as a perpendicular distance between the strike face and a top rail rear edge, between 0.15 inch and 0.30 inch. ### Claim 19 (depends on 17) The iron-type golf club head of claim 17, further comprises a rear perimeter comprising a top rail rear edge, a heel portion rear edge, a toe portion rear edge, and a sole rear edge. ### Claim 20 (depends on 19) The iron-type golf club head of claim 19, wherein the rear wall is recessed with respect to the rear perimeter.