Tennis racquet with adjustable frame isolation
OwnerPaul Richard Zarda, Jr.inventor
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Abstract
The present invention is directed to a racquet design with an inner and outer frame connected by an isolation system. Uniquely adapted to tennis racquets, the natural motion of the inner frame relative to the outer frame upon impact of the tennis ball on the inner frame will generate spin when the ball contacts the inner frame. The relationship between the inner frame, outer frame and isolation system can control the spin imparted to the ball for a given tennis swing. The tuning of the isolators relative to conventional racquet characteristics will increase the amount of ball spin caused by conventional racquets. The invention also increases the accuracy of the tennis ball's trajectory.
Claims21
A racquet comprising:
- an outer frame defined by a generally hoop shaped portion with a handle extending therefrom;
- an inner frame positionable within said outer frame having a string bed formed from a plurality of cross string elements and a plurality of main string elements;
- and a means for isolating and securing said inner frame to said outer frame constructed and arranged to allow for sway space deflection and to control overall in-plane stiffness between 30 lbs/in and 800 lbs/in and overall out-of-plane stiffness between 70 lbs/in and 600 lbs/in, said means for isolating and securing said inner frame to said outer frame combines out-of-plane stiffness, string bed stiffness, in-plane stiffness, and inner frame weight to provide increased spin to a ball impacting said string bed.
A tennis racquet comprising:
- an outer frame defined by a generally hoop shaped portion with a handle extending therefrom;
- an inner frame positionable within said outer frame having a string bed formed from a plurality of cross string elements and a plurality of main string elements;
- and a means for isolating and securing said inner frame to said outer frame constructed and arranged to allow for sway space deflection, said inner frame weighs between 20 grams and 200 grams, said means for isolating and securing said inner frame to said outer frame adjusted to provide an overall equivalent in-plane stiffness between 30 lbs/in and 800 lbs/in and an overall equivalent out-of-plane stiffness between 70 lbs/in and 600 lbs/in, whereby said means for isolating and securing said inner frame to said outer frame is adjustable wherein in-plane isolator stiffnesses, equivalent string-bed/ball stiffness, inner frame effective-mass, coefficient of friction between ball/strings sway space are adjusted so that out-of-plane ball-contact time approximately matches the half-period of the in-plane rigid-body motion of the inner-frame/string-bed stiffness to provide increase spin to a ball impacting said string bed.
Dependencies are inferred from the claim text.