# US 10,478,681 B2 · Weighted iron set > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,681 B2 - Document ID: US10478681B2 - Status: Granted - Kind: B2 - Application number: 15/896,852 - Filed: 2018-02-14 - Published: 2018-06-21 - Granted: 2019-11-19 - Earliest claimed: 2015-02-19 - Assignees: Acushnet Company - Applicants: Acushnet Company - Inventors: Michael E. Franz; Marni Ines; Jonathan Hebreo; Ryan J. A. Ritchie - Web page: https://patentgrep.com/patent/US10478681B2 ## CPC - A63B 53/047: {iron-type} - A63B 53/0475: {with one or more enclosed cavities} - A63B 60/02: Ballast means for adjusting the centre of mass (A63B60/24, A63B60/54 take precedence) - A63B 53/005: {Club sets} - A63B 53/0408: {characterised by specific dimensions, e.g. thickness} - A63B 53/0433: {with special sole configurations} - A63B 2053/0491: {with added weights, e.g. changeable, replaceable} - A63B 2209/00: Characteristics of used materials - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract The present invention is direct to a set of golf clubs comprising long irons, mid-irons and short irons. The invention contemplates the use of titanium or steel for the main body portion and significant tungsten weight members coupled to at least the toe and a heel weight member coupled in a hosel cavity. ## Claims ### Claim 1 A set of golf clubs comprising at least a first club head having a loft between about 15 and 25 degrees and a first club head mass, a second club head having a loft of between about 26 and 35 degrees and a second club head mass, and a third club head having a loft of about 36 degrees or greater and a third club head mass, the first club head comprising: a body made of steel comprising a heel, a toe, a topline, a sole, a hosel, a front face insert made of steel and a back wall forming a hollow cavity therebetween, a toe weight member formed of tungsten and coupled to a toe portion of the hollow cavity that comprises 25%-35% of the first club head mass; and a heel weight member formed of tungsten and coupled into a hosel cavity formed in a lower portion of the hosel, the heel weight member comprising 5%-10% of the first club head mass, wherein the heel weight member is enclosed in the hosel cavity by a steel cover member that forms at least a portion of the hosel. ### Claim 2 (depends on 1) The set of golf clubs of claim 1, wherein the second club head comprises: a second body made of steel comprising a second heel, a second toe, a second topline, a second sole, a second hosel, a second front face insert made of steel and a second back wall forming a second hollow cavity therebetween, and a second toe weight member formed of tungsten and coupled to a second toe portion of the second hollow cavity that comprises 25%-35% of the second club head mass. ### Claim 3 (depends on 2) The set of golf clubs of claim 2, wherein the first toe weight member and the second toe weight member are at least 65 grams each. ### Claim 4 (depends on 2) The set of golf clubs of claim 2, wherein the first club head and the second club head have a Moment of Inertia about the y-axis, extending vertically through a face center, of greater than 250 kg-mm2. ### Claim 5 (depends on 1) The set of golf clubs of claim 1, wherein the first club head has a Center of Gravity that is less than 18 mm from a ground surface when the club head is in the standard address position and is greater than 6 mm from a face center toward the back surface. ### Claim 6 (depends on 1) The set of golf clubs of claim 1, wherein the first club head has a Moment of Inertia about the y-axis of greater than 250 kg-mm2 and a blade length of less than 82 mm. ### Claim 7 A set of golf clubs comprising at least three first club heads having a loft between about 15 and 25 degrees and first club head masses, at least three second club heads having a loft of between about 26 and 35 degrees and second club head masses, and a third club head having a loft of about 36 degrees or greater and a third club head mass, each of the first club heads comprising: a body made of steel comprising a heel, a toe, a topline, a sole, a hosel, a front face insert made of steel and a back wall forming a hollow body having a first blade length, a toe weight member formed of tungsten and coupled to a lower toe portion of the hollow body that comprises 25%-35% of the first club head mass; and a heel weight member formed of tungsten and coupled a lower hosel portion of the body that comprises 5%-10% of the first club head mass; wherein the combined mass of the toe weight members and the heel weight members for the first club heads increases with loft; wherein the first club heads have a Center of Gravity that is less than 18 mm from a ground surface when the club head is in the standard address position and a Moment of Inertia about the y-axis of greater than 250 kg-mm2; and wherein at least one of the first club heads' Moment of Inertia about the y-axis, which extends vertically through a face center of the first club head, is greater than a second Moment of Inertia about the y-axis which extends vertically through a face center of at least one of the second club heads and less than a third Moment of Inertia about the y-axis which extends vertically through a face center of the third club head. ### Claim 8 (depends on 7) The set of golf clubs of claim 7, wherein the first blade lengths are less than 82 mm. ### Claim 9 (depends on 8) The set of golf clubs of claim 8, wherein the first club heads have a Moment of Inertia about the y-axis to blade length ratio of greater than 3 kg-mm. ### Claim 10 (depends on 9) The set of golf clubs of claim 9, wherein the Center of Gravity depth from the face center for the first club heads are almost 1/10 the first blade length. ### Claim 11 (depends on 7) The set of golf clubs of claim 7, wherein the second club heads have second Center of Gravities that are less than 19 mm from a ground surface when the club head is in the standard address position and the third club head has a third Center of Gravity that is less than 19 mm from a ground surface when the club head is in the standard address position. ### Claim 12 (depends on 7) The set of golf clubs of claim 7, wherein each of the club heads has a Center of Gravity height from the ground that increases with loft through the set. ### Claim 13 (depends on 7) The set of golf clubs of claim 7, wherein the Moment of Inertia about the y-axis for the first club heads increases with loft.