Title:
TENNIS RACKET
Document Type and Number:
Japanese Patent JPS6437967
Kind Code:
A
Abstract:
PURPOSE: To improve the preciseness of shot without being influenced by the flying passage of a ball by providing a design so that the frequency of a dominant vibration mode excited in a racket in play is made to coincide with the ball/racket contact period. CONSTITUTION: The height of a racket frame is continuously increased from a dimension A in the top of the head part of the frame to a dimension B in the throat part of the frame, the maximum height B is produced in the area where throat members 21, 22 are combined to a head part 20. The maximum dimension B is substantially conformed to the center of a frame piece 24 in which the frame piece crosses the vertical central line CL. When set to such form and dimension, the racket has rigidity larger than a general racket, and an inertial moment to an intermediate surface MP is provided so as to have a desired frequency from 170Hz to 250Hz to the first mode of bending under free-free suppression.
Inventors:
MAAKU ERU KARASEKU
Application Number:
JP21321087A
Publication Date:
February 08, 1989
Filing Date:
August 28, 1987
Export Citation:
Assignee:
WILSON SPORTING GOODS
International Classes:
A63B49/00; A63B49/02; A63B49/10; A63B59/00; (IPC1-7): A63B49/02
Domestic Patent References:
| JPS5317930A | 1978-02-18 | |||
| JPS59225A | 1984-01-05 |
Foreign References:
| US0031419A | 1861-02-12 |
Attorney, Agent or Firm:
Michiteru Soga