# US 12,109,463 B2 · 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 12,109,463 B2 - Document ID: US12109463B2 - Status: Granted - Kind: B2 - Application number: 18/087,580 - Filed: 2022-12-22 - Published: 2023-06-29 - Granted: 2024-10-08 - Earliest claimed: 2016-12-29 - Assignees: Taylor Made Golf Company, Inc. - Applicants: Taylor Made Golf Company, Inc - Inventors: Paul Demkowski; Matt Bovee; Mike Walker; Boo Ohashi; Connor Halberg - Web page: https://patentgrep.com/patent/US12109463B2 ## CPC - A63B 53/047: {iron-type} - A63B 60/00: Details or accessories of golf clubs, bats, rackets or the like - A63B 60/02: Ballast means for adjusting the centre of mass (A63B60/24, A63B60/54 take precedence) - A63B 60/50: with through-holes (A63B60/18 takes precedence; for stringing purposes A63B49/00) - A63B 53/0412: {Volume} - A63B 53/0433: {with special sole configurations} - A63B 53/0462: {characterised by tapering thickness of the impact face plate} - A63B 53/0466: {wood-type} - A63B 53/0475: {with one or more enclosed cavities} - A63B 60/52: with slits - A63B 60/54: with means for damping vibrations - A63B 2209/00: Characteristics of used materials - A63B 2209/02: with reinforcing fibres, e.g. carbon, polyamide fibres - A63B 2209/10: with adhesive type surfaces, i.e. hook and loop-type fastener - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract Disclosed herein is an iron-type golf club head that comprises a body, made of a first material having a first density. The iron-type golf club head also comprises a weight located within the internal cavity. The iron-type golf club head further comprises a filler material that has a density no less than 0.21 g/cc. The filler material has a mass no less than 2.5 grams and no more than 8 grams. The internal cavity has an internal cavity volume ranging between 5 cc to 20 cc. A ratio of the internal cavity volume to external club head volume ranges between 0.14 and 0.385. The internal cavity has a minimum front-to-back depth above a midplane of the golf club head of no less than 1.4 mm and a maximum front-to-back depth of the internal cavity above the midplane of the golf club head is no more than 13 mm. ## Claims ### Claim 1 An iron-type golf club head, comprising: a body, made of a body material having a body material density, wherein the body comprises: a heel portion; a toe portion; a sole portion, comprising an internal shelf; a top portion; a front portion, comprising a face opening; and a rear portion, comprising a rear wall extending from the sole portion to the top portion; a strike plate with a face maximum thickness Tfacemax, made of a strike plate material different than the body material, welded to the body and covering the face opening and thereby creating a strike face having a geometric center; a weight, made of a weight material having a weight density greater than the body material density, at least partially seated on the internal shelf and configured such that no portion of the weight defines an exterior surface of the golf club head, and the weight does not contact the strike plate; an internal cavity, having an internal cavity volume defined by the sole portion, the top portion, the strike face, and the rear portion; and an elastomer filler material, located within the internal cavity; wherein: the golf club head has an external club head volume ranging between 40 cc to 55 cc, a ratio of the internal cavity volume to an external club head volume is at least 0.14, and the internal cavity volume is no more than 20 cc; the golf club head has a maximum topline width Wtopline of 5.0-9.0 mm; the golf club head has a blade length (LB) of 73-83 mm; the weight has a weight height (HW), a weight depth (DW), a weight length (LW) that is greater than the weight depth (DW), and the weight length (LW) is no more than 65% of the blade length (LB); the weight density is at least 12 g/cc and the weight has a mass of at least 10 grams; the internal cavity has a topline-adjacent internal cavity depth proximate the top portion that is no more than 6 mm; a midplane is located halfway between a maximum toe height and a ground plane when the golf club head is in an address position, the internal cavity extends below the midplane and above the midplane, and above the midplane the internal cavity comprises: an above midplane maximum front-to-back cavity depth that is no more than 13 mm; and an above midplane minimum front-to-back cavity depth that is less than the above midplane maximum front-to-back cavity depth; the elastomer filler material extends above the midplane, and below the midplane; and an offset, in a front-to-rear direction, between a forwardmost portion of a hosel and a leading edge of the strike face is less than 4.0mm. ### Claim 2 (depends on 1) The iron-type golf club head of claim 1, wherein the above midplane maximum front-to-back cavity depth is no more than 12 mm, and the ratio of the internal cavity volume to the external club head volume is at least 0.22. ### Claim 3 (depends on 2) The iron-type golf club head of claim 2, wherein the strike plate further comprises a sole wrap portion that defines a part of the sole portion and forms a portion of the internal cavity, no portion of the sole wrap portion is welded to the sole portion at a location more than 11 mm rearward of a leading edge of the strike plate, the elastomer filler material contacts the sole wrap portion, and a sole wrap thickness Tsolewrap of the sole wrap portion is no more than 3.3 mm. ### Claim 4 (depends on 3) The iron-type golf club head of claim 3, wherein a center of gravity of the weight is located toeward of the geometric center of the strike face. ### Claim 5 (depends on 4) The iron-type golf club head of claim 4, further including an injection port extending through the toe portion to the internal cavity, a plug seals the injection port and has a plug mass of less than 15 grams, and the plug is located below the midplane. ### Claim 6 (depends on 5) The iron-type golf club head of claim 5, wherein the injection port has a port length of at least 7 mm. ### Claim 7 (depends on 5) The iron-type golf club head of claim 5, wherein a portion of the injection port opens to the internal cavity at an elevation above a portion of the weight. ### Claim 8 (depends on 4) The iron-type golf club head of claim 4, wherein the strike plate has a face minimum thickness Tfacemin of 1.1-2.7 mm, and the face minimum thickness Tfacemin is less than the face maximum thickness Tfacemax. ### Claim 9 (depends on 8) The iron-type golf club head of claim 8, wherein a portion of the weight is at least 20 mm toeward of the geometric center of the strike face. ### Claim 10 (depends on 9) The iron-type golf club head of claim 9, wherein a maximum weight height elevation (HWT) of the weight is less than a geometric center height (HGC) of the geometric center of the strike face. ### Claim 11 (depends on 10) The iron-type golf club head of claim 10, wherein the topline-adjacent internal cavity depth is no more than 4.5 mm. ### Claim 12 (depends on 11) The iron-type golf club head of claim 11, wherein a topline thickness Ttopline of the top portion is less than the face maximum thickness Tfacemax. ### Claim 13 (depends on 11) The iron-type golf club head of claim 11, wherein a portion of a peripheral weld along a top perimeter of the strike plate is on the front portion and is below the top portion, and the elastomer filler material extends above the top perimeter of the strike plate. ### Claim 14 (depends on 10) The iron-type golf club head of claim 10, wherein a ratio of the sole wrap thickness Tsolewrap to the face maximum thickness Tfacemax is at least 0.40. ### Claim 15 (depends on 10) The iron-type golf club head of claim 10, wherein a portion of the sole wrap portion is welded to the sole portion at a location at least 4 mm rearward of a leading edge of the strike face. ### Claim 16 (depends on 10) The iron-type golf club head of claim 10, wherein the maximum topline width Wtopline is no more than 6.5 mm. ### Claim 17 (depends on 10) The iron-type golf club head of claim 10, wherein a ratio of a topline thickness Ttopline to the face maximum thickness Tfacemax is between 0.4 and 1.0. ### Claim 18 (depends on 10) The iron-type golf club head of claim 10, wherein the weight length (LW) is at least 35% of the blade length (LB). ### Claim 19 (depends on 18) The iron-type golf club head of claim 18, wherein the elastomer filler material has a filler material density of less than 0.71 g/cc. ### Claim 20 (depends on 19) The iron-type golf club head of claim 19, wherein the golf club head has a center of gravity located at a Z-up elevation above the ground plane, the maximum weight height elevation (HWT) of the weight is less than the Z-up elevation, and the rear wall, above the midplane and adjacent to the internal cavity, has a rear wall thickness Trear less than the face maximum thickness Tfacemax. ### Claim 21 (depends on 20) The iron-type golf club head of claim 20, wherein the filler material density is less than 0.49 g/cc. ### Claim 22 (depends on 21) The iron-type golf club head of claim 21, wherein the sole portion includes a back-constraining wall, the internal shelf extends from the back-constraining wall, and the back-constraining wall is parallel to an external surface of the strike face. ### Claim 23 (depends on 22) The iron-type golf club head of claim 22, wherein the sole portion includes an upper-constraining wall extending from the back-constraining wall, and a portion of the weight is between the internal shelf and the upper-constraining wall. ### Claim 24 (depends on 21) The iron-type golf club head of claim 21, wherein the above midplane maximum front-to-back cavity depth is no more than 10 mm. ### Claim 25 (depends on 21) The iron-type golf club head of claim 21, wherein the ratio of the internal cavity volume to the external club head volume is no more than 0.385. ### Claim 26 (depends on 21) The iron-type golf club head of claim 21, wherein the rear wall thickness Trear, above the midplane of the golf club head and adjacent to the internal cavity, is less than 2 mm. ### Claim 27 (depends on 21) The iron-type golf club head of claim 21, wherein the elastomer filler material has a filler has a filler material mass of 2-10 grams. ### Claim 28 (depends on 21) The iron-type golf club head of claim 21, wherein the Z-up elevation is 17.9-20 mm. ### Claim 29 (depends on 21) The iron-type golf club head of claim 21, wherein the face minimum thickness Tfacemin is less than 2 mm, and the face maximum thickness Tfacemax is less than 2.85 mm. ### Claim 30 (depends on 21) The iron-type golf club head of claim 21, wherein the golf club head has a coefficient of restitution value greater than 0.79 as measured according to the United States Golf Association (USGA) rules set forth in the Procedure for Measuring the Velocity Ratio of a Club Head for Conformance to Rule 4-1e, Appendix II Revision 2 Feb. 8, 1999. ### Claim 31 (depends on 21) The iron-type golf club head of claim 21, wherein a top perimeter of the strike plate extends to the top portion, and the top perimeter of the strike plate is welded to the top portion. ### Claim 32 (depends on 21) The iron-type golf club head of claim 21, further including an injection port extending through the toe portion to the internal cavity, and a plug seals the injection port and has a plug mass of less than 15 grams. ### Claim 33 (depends on 32) The iron-type golf club head of claim 32, wherein the injection port has a port length of at least 7 mm. ### Claim 34 (depends on 32) The iron-type golf club head of claim 32, wherein a portion of the injection port opens to the internal cavity at an elevation above a portion of the weight. ### Claim 35 (depends on 1) The iron-type golf club head of claim 1, wherein a first front-to-back depth of the internal cavity is proximate the midplane of the golf club head, a second front-to-back depth of the internal cavity is proximate the top portion, and a third front-to-back depth of the internal cavity is located in between the midplane of the golf club and the top portion, wherein the third front-to-back depth is less than the first front-to-back depth and the second front-to-back depth. ### Claim 36 (depends on 35) The iron-type golf club head of claim 35, wherein the third front-to-back depth is less than 5 mm. ### Claim 37 An iron-type golf club head, comprising: a body, made of a body material having a body material density, wherein the body comprises: a heel portion; a toe portion; a sole portion, comprising an internal shelf; a top portion; a front portion, comprising a face opening; and a rear portion, comprising a rear wall extending from the sole portion to the top portion; a strike plate with a face maximum thickness Tfacemax, made of a strike plate material different than the body material, welded to the body and covering the face opening and thereby creating a strike face having a geometric center; a weight, made of a weight material having a weight density greater than the body material density, at least partially seated on the internal shelf and configured such that no portion of the weight defines an exterior surface of the golf club head, the weight does not contact the strike plate, and a center of gravity of the weight is located toeward of the geometric center of the strike face; an internal cavity, having an internal cavity volume defined by the sole portion, the top portion, the strike face, and the rear portion; an elastomer filler material, located within the internal cavity; and an injection port extending through a portion of the body to the internal cavity with a portion of the injection port opening to the internal cavity at an elevation above a portion of the weight, and a plug sealing the injection port and having a plug mass of less than 15 grams; wherein: the golf club head has an external club head volume ranging between 40 cc to 55 cc, a ratio of the internal cavity volume to an external club head volume is at least 0.22, and the internal cavity volume is no more than 20 cc; the golf club head has a maximum topline width Wtopline of 5.0-9.0 mm; the golf club head has a blade length (LB) of 73-83 mm; the weight has a weight height (HW), a weight depth (DW), a weight length (LW) that is greater than the weight depth (DW), and the weight length (LW) is no more than 65% of the blade length (LB); the weight density is at least 12 g/cc and the weight has a mass of at least 10 grams; the internal cavity has a topline-adjacent internal cavity depth proximate the top portion that is no more than 6 mm; a midplane is located halfway between a maximum toe height and a ground plane when the golf club head is in an address position, the internal cavity extends below the midplane and above the midplane, and above the midplane the internal cavity comprises: an above midplane maximum front-to-back cavity depth that is no more than 12 mm; and an above midplane minimum front-to-back cavity depth that is less than the above midplane maximum front-to-back cavity depth; the elastomer filler material extends above the midplane, and below the midplane; an offset, in a front-to-rear direction, between a forwardmost portion of a hosel and a leading edge of the strike face is less than 4.0 mm; the strike plate further comprises a sole wrap portion that defines a part of the sole portion and forms a portion of the internal cavity, a portion of the sole wrap portion is welded to the sole portion, the elastomer filler material contacts the sole wrap portion, and a sole wrap thickness Tsolewrap of the sole wrap portion is no more than 3.3 mm; and the plug is located below the midplane. ### Claim 38 (depends on 37) The iron-type golf club head of claim 37, wherein the above midplane maximum front-to-back cavity depth is no more than 12 mm, and the ratio of the internal cavity volume to the external club head volume is at least 0.22. ### Claim 39 (depends on 37) The iron-type golf club head of claim 37, wherein a first front-to-back depth of the internal cavity is proximate the midplane of the golf club head, a second front-to-back depth of the internal cavity is proximate the top portion, and a third front-to-back depth of the internal cavity is located in between the midplane of the golf club and the top portion, wherein the third front-to-back depth is less than the first front-to-back depth and the second front-to-back depth. ### Claim 40 (depends on 39) The iron-type golf club head of claim 39, wherein the third front-to-back depth is less than 5 mm. ### Claim 41 (depends on 37) The iron-type golf club head of claim 37, wherein the injection port extends through the toe portion to the internal cavity. ### Claim 42 (depends on 41) The iron-type golf club head of claim 41, wherein the injection port has a port length of at least 7 mm. ### Claim 43 (depends on 37) The iron-type golf club head of claim 37, wherein the strike plate has a face minimum thickness Tfacemin of 1.1-2.7 mm, and the face minimum thickness Tfacemin is less than the face maximum thickness Tfacemax. ### Claim 44 (depends on 37) The iron-type golf club head of claim 37, wherein a portion of the weight is at least 20 mm toeward of the geometric center of the strike face. ### Claim 45 (depends on 44) The iron-type golf club head of claim 44, wherein a maximum weight height elevation (HWT) of the weight is less than a geometric center height (HGC) of the geometric center of the strike face. ### Claim 46 (depends on 44) The iron-type golf club head of claim 44, wherein a portion of a peripheral weld along a top perimeter of the strike plate is on the front portion and is below the top portion, and the elastomer filler material extends above the top perimeter of the strike plate. ### Claim 47 (depends on 44) The iron-type golf club head of claim 44, wherein the weight length (LW) is at least 35% of the blade length (LB). ### Claim 48 (depends on 44) The iron-type golf club head of claim 44, wherein the elastomer filler material has a filler material density of less than 0.71 g/cc. ### Claim 49 (depends on 48) The iron-type golf club head of claim 48, wherein the golf club head has a center of gravity located at a Z-up elevation above the ground plane, the maximum weight height elevation (HWT) of the weight is less than the Z-up elevation, and a portion of the rear wall, above the midplane and adjacent to the internal cavity, has a rear wall thickness Trear less than the face maximum thickness Tfacemax. ### Claim 50 (depends on 48) The iron-type golf club head of claim 48, wherein the filler material density is less than 0.49 g/cc, and a portion of the rear wall thickness Trear, above the midplane of the golf club head and adjacent to the internal cavity, is less than 2 mm. ### Claim 51 (depends on 50) The iron-type golf club head of claim 50, wherein the sole portion includes a back-constraining wall, the internal shelf extends from the back-constraining wall, and the back-constraining wall is parallel to an external surface of the strike face. ### Claim 52 (depends on 51) The iron-type golf club head of claim 51, wherein the sole portion includes an upper-constraining wall extending from the back-constraining wall, and a portion of the weight is between the internal shelf and the upper-constraining wall. ### Claim 53 (depends on 44) The iron-type golf club head of claim 44, wherein the ratio of the internal cavity volume to the external club head volume is no more than 0.385. ### Claim 54 (depends on 53) The iron-type golf club head of claim 53, wherein a portion of the rear wall thickness Trear, above the midplane of the golf club head and adjacent to the internal cavity, is less than 2 mm. ### Claim 55 (depends on 54) The iron-type golf club head of claim 54, wherein the face minimum thickness Tfacemin is less than 2 mm, and the face maximum thickness Tfacemax is less than 2.85 mm. ### Claim 56 (depends on 44) The iron-type golf club head of claim 44, wherein the golf club head has a coefficient of restitution value greater than 0.79 as measured according to the United States Golf Association (USGA) rules set forth in the Procedure for Measuring the Velocity Ratio of a Club Head for Conformance to Rule 4-1e, Appendix II Revision 2 Feb. 8, 1999. ### Claim 57 (depends on 44) The iron-type golf club head of claim 44, wherein a top perimeter of the strike plate extends to the top portion, and the top perimeter of the strike plate is welded to the top portion. ### Claim 58 (depends on 37) The iron-type golf club head of claim 37, wherein the topline-adjacent internal cavity depth is no more than 4.5 mm. ### Claim 59 (depends on 37) The iron-type golf club head of claim 37, wherein a topline thickness Ttopline of the top portion is less than the face maximum thickness Tfacemax. ### Claim 60 (depends on 37) The iron-type golf club head of claim 37, wherein a ratio of the sole wrap thickness Tsolewrap to the face maximum thickness Tfacemax is at least 0.40. ### Claim 61 (depends on 60) The iron-type golf club head of claim 60, wherein a portion of the sole wrap portion is welded to the sole portion at a location at least 4 mm rearward of a leading edge of the strike face. ### Claim 62 (depends on 61) The iron-type golf club head of claim 61, wherein a ratio of a topline thickness Ttopline to the face maximum thickness Tfacemax is between 0.4 and 1.0. ### Claim 63 An iron-type golf club head, comprising: a body, made of a body material having a body material density, wherein the body comprises: a heel portion; a toe portion; a sole portion, comprising an internal shelf; a top portion; a front portion, comprising a face opening; and a rear portion, comprising a rear wall extending from the sole portion to the top portion; a strike plate with a face maximum thickness Tfacemax and a face minimum thickness Tfacemin of 1.1-2.7 mm and less than the face maximum thickness Tfacemax, the strike plate made of a strike plate material different than the body material, welded to the body and covering the face opening and thereby creating a strike face having a geometric center; a weight, made of a weight material having a weight density greater than the body material density, at least partially seated on the internal shelf and configured such that no portion of the weight defines an exterior surface of the golf club head, and the weight does not contact the strike plate, a portion of the weight is at least 20 mm toeward of the geometric center of the strike face, and a maximum weight height elevation (HWT) of the weight is less than a geometric center height (HGC) of the geometric center of the strike face; an internal cavity, having an internal cavity volume defined by the sole portion, the top portion, the strike face, and the rear portion; an elastomer filler material, located within the internal cavity; and an injection port extending through a portion of the body to the internal cavity with a portion of the injection port opening to the internal cavity at an elevation above a portion of the weight, and a plug sealing the injection port and having a plug mass of less than 15 grams; wherein: the golf club head has an external club head volume ranging between 40 cc to 55 cc, a ratio of the internal cavity volume to an external club head volume is at least 0.14, and the internal cavity volume is no more than 20 cc; the golf club head has a maximum topline width Wtopline of 5.0-9.0 mm; the golf club head has a blade length (LB) of 73-83 mm; the weight has a weight height (HW), a weight depth (DW), a weight length (LW) that is greater than the weight depth (DW), and the weight length (LW) is no more than 65% of the blade length (LB); the weight density is at least 12 g/cc and the weight has a mass of at least 10 grams; the internal cavity has a topline-adjacent internal cavity depth proximate the top portion that is no more than 6 mm; a midplane is located halfway between a maximum toe height and a ground plane when the golf club head is in an address position, the internal cavity extends below the midplane and above the midplane, and above the midplane the internal cavity comprises: an above midplane maximum front-to-back cavity depth that is no more than 13 mm; and an above midplane minimum front-to-back cavity depth that is less than the above midplane maximum front-to-back cavity depth; the elastomer filler material extends above the midplane, and below the midplane, and below a portion of the weight; and an offset, in a front-to-rear direction, between a forwardmost portion of a hosel and a leading edge of the strike face is less than 4.0 mm. ### Claim 64 (depends on 63) The iron-type golf club head of claim 63, wherein the above midplane maximum front-to-back cavity depth is no more than 12 mm, and the ratio of the internal cavity volume to the external club head volume is at least 0.22. ### Claim 65 (depends on 63) The iron-type golf club head of claim 63, wherein a first front-to-back depth of the internal cavity is proximate the midplane of the golf club head, a second front-to-back depth of the internal cavity is proximate the top portion, and a third front-to-back depth of the internal cavity is located in between the midplane of the golf club and the top portion, wherein the third front-to-back depth is less than the first front-to-back depth and the second front-to-back depth. ### Claim 66 (depends on 65) The iron-type golf club head of claim 65, wherein the third front-to-back depth is less than 5 mm. ### Claim 67 (depends on 63) The iron-type golf club head of claim 63, wherein the injection port extends through the toe portion to the internal cavity. ### Claim 68 (depends on 67) The iron-type golf club head of claim 67, wherein the injection port has a port length of at least 7 mm. ### Claim 69 (depends on 67) The iron-type golf club head of claim 67, wherein a portion of the injection port opens to the internal cavity at an elevation above a portion of the weight. ### Claim 70 (depends on 63) The iron-type golf club head of claim 63, wherein a center of gravity of the weight is located toeward of the geometric center of the strike face. ### Claim 71 (depends on 63) The iron-type golf club head of claim 63, wherein the topline-adjacent internal cavity depth is no more than 4.5 mm. ### Claim 72 (depends on 71) The iron-type golf club head of claim 71, wherein a topline thickness Ttopline of a portion of the top portion is less than the face maximum thickness Tfacemax. ### Claim 73 (depends on 63) The iron-type golf club head of claim 63, wherein a portion of a peripheral weld along a top perimeter of the strike plate is on the front portion and is below the top portion, and the elastomer filler material extends above the top perimeter of the strike plate. ### Claim 74 (depends on 63) The iron-type golf club head of claim 63, wherein the strike plate further comprises a sole wrap portion that defines a part of the sole portion and forms a portion of the internal cavity, and the elastomer filler material contacts the sole wrap portion. ### Claim 75 (depends on 74) The iron-type golf club head of claim 74, wherein a portion of the sole wrap portion has (a) a sole wrap thickness Tsolewrap of no more than 3.3 mm, and (b) a ratio of the sole wrap thickness Tsolewrap to the face maximum thickness Tfacemax of at least 0.40. ### Claim 76 (depends on 74) The iron-type golf club head of claim 74, wherein a portion of the sole wrap portion is welded to the sole portion at a location at least 4 mm rearward of a leading edge of the strike face. ### Claim 77 (depends on 63) The iron-type golf club head of claim 63, wherein a ratio of a topline thickness Ttopline to the face maximum thickness Tfacemax is between 0.4 and 1.0. ### Claim 78 (depends on 63) The iron-type golf club head of claim 63, wherein the weight length (LW) is at least 35% of the blade length (LB). ### Claim 79 (depends on 63) The iron-type golf club head of claim 63, wherein the elastomer filler material has a filler material density of less than 0.71 g/cc. ### Claim 80 (depends on 79) The iron-type golf club head of claim 79, wherein the golf club head has a center of gravity located at a Z-up elevation above the ground plane, and the maximum weight height elevation (HWT) of the weight is less than the Z-up elevation. ### Claim 81 (depends on 79) The iron-type golf club head of claim 79, wherein the filler material density is less than 0.49 g/cc. ### Claim 82 (depends on 63) The iron-type golf club head of claim 63, wherein the sole portion includes a back-constraining wall, the internal shelf extends from the back-constraining wall. ### Claim 83 (depends on 82) The iron-type golf club head of claim 82, wherein the sole portion includes an upper-constraining wall extending from the back-constraining wall, and a portion of the weight is between the internal shelf and the upper-constraining wall. ### Claim 84 (depends on 63) The iron-type golf club head of claim 63, wherein the ratio of the internal cavity volume to the external club head volume is no more than 0.385. ### Claim 85 (depends on 84) The iron-type golf club head of claim 84, wherein a portion of the rear wall thickness Trear, above the midplane of the golf club head and adjacent to the internal cavity, is less than 2 mm. ### Claim 86 (depends on 84) The iron-type golf club head of claim 84, wherein the face minimum thickness Tfacemin is less than 2 mm, and the face maximum thickness Tfacemax is less than 2.85 mm. ### Claim 87 (depends on 84) The iron-type golf club head of claim 84, wherein the golf club head has a coefficient of restitution value greater than 0.79 as measured according to the United States Golf Association (USGA) rules set forth in the Procedure for Measuring the Velocity Ratio of a Club Head for Conformance to Rule 4-1e, Appendix II Revision 2 Feb. 8, 1999. ### Claim 88 (depends on 84) The iron-type golf club head of claim 84, wherein a top perimeter of the strike plate extends to the top portion, and the top perimeter of the strike plate is welded to the top portion.