Tennis racket having improved strength factor

Claim 1

A tennis racket structure comprising: a frame strip for defining a stringing section and a handle section; said frame strip comprising an extruded metal frame strip having a pair of opposed outer tubular sections connected by a web and being shaped to partially define a generally oval section and a pair of spaced apart generally parallel handle end sections and said web cooperating with said pair of tubular sections to define on one side thereof a generally rectangular channel and on the other side thereof a generally trapezoidal channel; said frame strip having a cross-sectional configuration for defining a strength factor (IYs/A) in the range of 0.0516(in2) Ys to 0.0580 (in2)Ys wherein the strength factor is the ratio of the moment of inertia I(in4) of the frame strip around the longitudinal axis thereof to the transverse cross-sectional area A(in2) of the strip material, and Ys is the yield stress of the strip material; a throat piece consisting solely of plastic and including a pair of opposed surfaces shaped complementarily to conform to the shape of said generally trapezoidal channel of said frame strip and wherein said plastic throat piece possesses such flexibility and resiliency as to prevent deformation in torsion in the throat area of the tennis racket frame in normal play; and handle means.