US 12,257,764 B1
Bent composite golf club shaft and methods for manufacturing bent composite golf club shafts
Logan K. Johnston, Vista, CA (US); Robert Gonczi, Oceanside, CA (US); Brandon D. DeMille, Carlsbad, CA (US); and Patrick Dawson, Poway, CA (US)
Assigned to Topgolf Callaway Brands Corp., Carlsbad, CA (US)
Filed by Callaway Golf Company, Carlsbad, CA (US)
Filed on Nov. 13, 2021, as Appl. No. 17/525,892.
Application 17/525,892 is a continuation in part of application No. 17/497,059, filed on Oct. 8, 2021.
Application 17/525,892 is a continuation in part of application No. 17/497,643, filed on Oct. 8, 2021, abandoned.
Claims priority of provisional application 63/091,434, filed on Oct. 14, 2020.
Claims priority of provisional application 63/091,407, filed on Oct. 14, 2020.
Int. Cl. B29C 53/42 (2006.01); A63B 53/10 (2015.01); B29C 53/08 (2006.01); B29C 53/56 (2006.01); B29C 53/80 (2006.01); B29K 705/00 (2006.01); B29L 31/52 (2006.01)
CPC B29C 53/566 (2013.01) [B29C 53/08 (2013.01); B29C 53/80 (2013.01); A63B 53/10 (2013.01); B29K 2705/00 (2013.01); B29L 2031/5227 (2013.01)] 3 Claims
OG exemplary drawing
 
1. A method of manufacturing a golf club shaft comprising the steps of:
cutting composite material into a plurality of composite pieces;
engaging a flexible core with a rod composed of a rigid material;
wrapping the composite pieces around the flexible core and rod combination to form a first precursor shaft;
rolling the first precursor shaft to form a straight, second precursor shaft;
wrapping tape around the second precursor shaft;
partially curing the second precursor shaft to form a third precursor shaft with a tip;
removing the flexible core and rod combination from the third precursor shaft;
placing a bladder in the third precursor shaft and inflating the bladder;
placing the tip in a forming mold while the tip is at a temperature above Tg;
bending the tip within the forming mold to form a fourth precursor shaft with a first bend having a first bend angle of 20 to 25 degrees relative to the non-tip shaft;
bending the tip within the forming mold to form the fourth precursor shaft with a second bend having a second bend angle of 12 to 16 degrees relative to the first bend angle;
curing the fourth precursor shaft;
removing the flexible core and rod combination from the fourth precursor shaft; and
applying cosmetic features to the fourth precursor shaft to create the final golf club shaft.