Patent ID: 6609429
Filing Date: 2003-08-26
Classification: A63B,G01H,G01N,Y10T

Abstract:
Apparatus for measuring asymmetry of a golf club shaft about a longitudinal axis thereof, said golf club shaft having a proximal end for gripping by a golfer and a distal end for attachment to a golf club head, said apparatus comprising:clamp for immobilizing a first one of said proximal end and said distal end of said golf club shaft; a restraint for maintaining a second one of said proximal end and said distal end in a displaced condition in a direction other than parallel to said longitudinal axis; a force transducer for measuring force tending to restore said second one of said proximal end and said distal end from said displaced condition, said clamp being rotated through at least about 360Â° of angular displacement during said measuring, while maintaining said second one of said proximal end and said distal end in said displaced condition, thereby obtaining a plurality of restoring force measurements at different angular displacements; memory in which said plurality of restoring force measurement is stored in association with angular displacement; and a processor programmed to calculate, from said plurality of restoring force measurements associated with angular displacement, an index derived from a formula and representative of said asymmetry, by: selecting, from said measured force associated with angular displacement, a maximum force Pmax and a minimum force Pmin; and computing said index, LSI, according to the following formula: LSI=100(1âˆ’(Pmaxâˆ’Pmin)/Pmax)).