US 11,918,873 B2
Diameter profiled golf club shaft to reduce drag
David S. Kultala, Phoenix, AZ (US); Martin R. Jertson, Phoenix, AZ (US); and Ryan M. Stokke, Anthem, AZ (US)
Assigned to Karsten Manufacturing Corporation, Phoenix, AZ (US)
Filed by KARSTEN MANUFACTURING CORPORATION, Phoenix, AZ (US)
Filed on Jan. 26, 2022, as Appl. No. 17/649,048.
Application 17/649,048 is a continuation of application No. 16/941,444, filed on Jul. 28, 2020, granted, now 11,235,214.
Application 16/941,444 is a continuation of application No. 16/355,482, filed on Mar. 15, 2019, granted, now 10,758,796, issued on Sep. 1, 2020.
Application 16/355,482 is a continuation of application No. 15/798,002, filed on Oct. 30, 2017, granted, now 10,272,304, issued on Apr. 30, 2019.
Claims priority of provisional application 62/414,492, filed on Oct. 28, 2016.
Prior Publication US 2022/0143479 A1, May 12, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. A63B 53/10 (2015.01); A63B 53/02 (2015.01); A63B 60/00 (2015.01); A63B 53/04 (2015.01)
CPC A63B 60/00 (2015.10) [A63B 53/02 (2013.01); A63B 53/10 (2013.01); A63B 53/0466 (2013.01); A63B 53/047 (2013.01); A63B 2053/0479 (2013.01); A63B 60/0081 (2020.08); A63B 2209/00 (2013.01); A63B 2209/02 (2013.01); A63B 2225/01 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A golf club comprising:
a golf club head comprising a strike face and a hosel;
a shaft adapter secured within a hosel internal bore;
wherein the shaft adapter further comprises a generally tubular body having a shaft adapter inner bore adapted to receive a golf club shaft, and an outer profile or surface adapted to be secured within the hosel internal bore;
the golf club shaft formed from a fiber reinforced polymer and extending along a longitudinal axis between a tip end and a grip end, the golf club shaft including:
a tip end section abutting the tip end, wherein the tip end section is at least partially secured within the inner bore of the shaft adapter;
a grip end section abutting the grip end; and
a tapered section interconnecting the tip end section and the grip end section, wherein:
the tapered section includes an upper 60% and a lower 60% along the longitudinal axis, the upper 60% abutting the grip end section, and the lower 60% abutting the tip end section, and
the tapered section has a length of greater than about 30 inches, wherein:
a first region is located entirely within about a first 15 inches of the tapered section closest to the tip end section:
the tapered section further including:
a reference portion at least partially located within the upper 60%, wherein an outer surface of the reference portion has a frustoconical shape with a near-constant taper rate;
a narrowed portion at least partially located within the lower 60% and between the tip end and the reference portion, wherein an outer surface of the narrowed portion is recessed relative to a reference surface extrapolated from the frustoconical shape toward the tip end;
wherein the fiber reinforced polymer of the narrowed portion comprises a plurality of fibers oriented parallel to a longitudinal axis (0-degree fibers).