US 12,420,153 B2
Shaft for golf club
Dustin A. Barksdale, San Marcos, CA (US); Donald S. Bone, Escondido, CA (US); Charles E. Golden, Encinitas, CA (US); Noah de la Cruz, San Diego, CA (US); Steven Scott Ogg, Carlsbad, CA (US); and Parker Rosquist, Vista, CA (US)
Assigned to ACUSHNET COMPANY, Fairhaven, MA (US)
Filed by Acushnet Company, Fairhaven, MA (US)
Filed on Dec. 27, 2021, as Appl. No. 17/562,905.
Application 17/562,905 is a continuation in part of application No. 17/544,033, filed on Dec. 7, 2021, granted, now 12,179,076.
Prior Publication US 2023/0173352 A1, Jun. 8, 2023
Int. Cl. A63B 53/10 (2015.01); A63B 53/02 (2015.01); A63B 53/04 (2015.01)
CPC A63B 53/10 (2013.01) [A63B 53/0433 (2020.08); A63B 53/0437 (2020.08); A63B 53/0466 (2013.01); A63B 53/023 (2020.08); A63B 2225/01 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A golf club comprising:
a golf club head;
a grip; and
a shaft having a tip end and a butt end, the golf club head being coupled to the shaft at the tip end, the grip being coupled to the shaft at the butt end, and an average bending stiffness of a butt end portion of the shaft being greater than 4.9 times an average bending stiffness of a tip end portion of the shaft,
wherein the tip end portion extends in a tip-to-butt direction from 150 mm from the tip end to 300 mm from the tip end,
wherein the butt end portion extends in the tip-to-butt direction from 800 mm from the tip end to 950 mm from the tip end, and
wherein a rate of change of bending stiffness in a tip-to-butt direction, at a point along a middle portion between the tip end portion and the butt end portion, is at least 2.7 times an average rate of change of bending stiffness of the butt end portion.