# US 2018/0021646 A1 · Variable wall bat > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0021646 A1 - Document ID: US20180021646A1 - Status: Published application - Kind: A1 - Application number: 15/487,649 - Filed: 2017-04-14 - Published: 2018-01-25 - Earliest claimed: 2016-07-22 - Assignees: Rawlings Sporting Goods Company, Inc. - Applicants: Rawlings Sporting Goods Company, Inc. - Inventors: Rebecca O'Hara; Nicole McLeod - Web page: https://patentgrep.com/patent/US20180021646A1 ## CPC - A63B 59/58: characterised by the shape (A63B59/55, A63B59/56 take precedence) - A63B 59/51: made of metal - A63B 60/00: Details or accessories of golf clubs, bats, rackets or the like - A63B 59/56: characterised by the head - A63B 2102/18: Baseball, rounders or similar games - A63B 2102/182: {Softball} - A63B: APPARATUS FOR PHYSICAL TRAINING, GYMNASTICS, SWIMMING, CLIMBING, OR FENCING; BALL GAMES; TRAINING EQUIPMENT (apparatus for passive exercising, massage A61H) ## Abstract A barrel for a ball bat having a first inside surface and an outside surface, and a first thickness represented by the distance between the first inside surface and the outside surfaces. The first thickness of the barrel is generally uniform except at one or more locations within the ball impact area of the bat. However, the barrel may include one or more than one thick section relative to the uniform thickness of the rest of the barrel of the bat. In addition, the barrel may include one or more than one thin section relative to the uniform thickness of the rest of the barrel of the bat. The shoulders between the thick and/or thin section(s) and the uniform thickness of the remainder of the bat may be relatively abrupt. ## Claims ### Claim 1 A barrel for a ball bat, the barrel comprising: a barrel portion and a transition section, the barrel portion having a constant outer diameter and the transition section having an outer diameter that tapers from the barrel portion toward an attachment end of the transition section; a ball impact area extending from an end-cap end of the barrel portion along the barrel portion and at least a portion of the transition section, wherein the ball impact area has a first thickness measured between an outer surface and a first inner surface section; at least one thick section positioned along the ball impact area, said at least one thick section having a second thickness measured between the outer surface and a second inner surface section; at least one thin section positioned along the ball impact area, said at least one thin section having a third thickness measured between the outer surface and a third inner surface section; and at least one shoulder transitioning between adjacent portions of the barrel having different thicknesses; wherein the bat has a weight drop of −4 or greater. ### Claim 2 (depends on 1) The barrel of claim 1 wherein the first thickness is less than the second thickness, and the first thickness is thicker than the third thickness. ### Claim 3 (depends on 2) The barrel of claim 2 wherein the second thickness is between about 0.170 and 0.200 inches. ### Claim 4 (depends on 2) The barrel of claim 2 wherein the third thickness is between about 0.065 and 0.120 inches. ### Claim 5 (depends on 4) The barrel of claim 4 wherein the third thickness is between about 0.075 and 0.100 inches. ### Claim 6 (depends on 1) The barrel of claim 1 wherein the first thickness is less than the second thickness, and the first thickness is equal to the third thickness. ### Claim 7 (depends on 6) The barrel of claim 6 wherein the second thickness is between about 0.170 and 0.200 inches. ### Claim 8 (depends on 7) The barrel of claim 7 wherein the third thickness is between about 0.065 and 0.120 inches. ### Claim 9 (depends on 8) The barrel of claim 8 wherein the third thickness is between about 0.075 and 0.100 inches. ### Claim 10 (depends on 1) The barrel of claim 1 wherein a ratio between the second and third thicknesses is greater than 1.6. ### Claim 11 (depends on 1) The barrel of claim 1 wherein a ratio between the second and third thicknesses is between about 1.7 and 2.27. ### Claim 12 (depends on 1) The barrel of claim 1 wherein the barrel portion is between about three and eight inches in length axially. ### Claim 13 (depends on 1) The barrel of claim 1 wherein at least one said thick section is between about 1 and 2 inches in length axially, not including any shoulders. ### Claim 14 (depends on 1) The barrel of claim 1 wherein at least one said thick section is between about 1.5 and 2 inches in length axially, not including any shoulders. ### Claim 15 (depends on 1) The barrel of claim 1 wherein a ratio between an axial length of the barrel portion and an axial length of a said thick section, not including any shoulders, is between about 1.5 and 5.67. ### Claim 16 (depends on 1) The barrel of claim 1 wherein a ratio between an axial length of a said thick section and the second thickness is between about 8.11 and 11.76. ### Claim 17 (depends on 1) The barrel of claim 1 wherein a ratio between an axial length of the barrel portion and the second thickness is between about 17.65 and 50. ### Claim 18 (depends on 1) The barrel of claim 1 wherein a shoulder has an axial length of about 0.5 inches or less. ### Claim 19 (depends on 1) The barrel of claim 1 wherein each shoulder has an axial length of about 0.5 inches or less. ### Claim 20 A barrel for a ball bat, the barrel comprising: a barrel portion and a transition section, the barrel portion having a constant outer diameter and the transition section having an outer diameter that tapers from the barrel portion toward an attachment end of the transition section; a ball impact area extending from an end-cap end of the barrel portion along the barrel portion and at least a portion of the transition section, wherein the ball impact area has a first thickness measured between an outer surface and a first inner surface section; at least one thick section positioned along the ball impact area, said at least one thick section having a second thickness measured between the outer surface and a second inner surface section, said at least one thick section having an axial length of between about 1 and 2 inches; at least one thin section positioned along the ball impact area, said at least one thin section having a third thickness measured between the outer surface and a third inner surface section; and at least one shoulder transitioning between adjacent portions of the barrel having different thicknesses, said at least one shoulder having an axial length of about 0.5 inches or less; wherein a ratio between the second and third thicknesses is above about 1.6. ### Claim 21 (depends on 20) The barrel of claim 20, wherein a ratio between the axial length of a said thick section and the second thickness is between about 5.5 and 11.76. ### Claim 22 (depends on 20) The barrel of claim 20, wherein a ratio between an axial length of the barrel portion and the second thickness is between about 23.5 and 29.5.