| 摘要 |
FIELD: sports. ^ SUBSTANCE: invention relates to sports equipment. Racket is fixed in machine and fixed. Prior to tightening, string is stretched in three stages with maximum force of 40-50 kg. Duration of stretching in each stage makes 30-60 seconds. Length of string when stretched at the first stage increases by 50% from the maximum value of extension. At the second stage of stretching, length of string increases by 20-30%. At the third stage of stretching, string extends by another 20-30%. ^ EFFECT: improved operational characteristics of rocket string surface by means of preliminary preparation of string prior to its tightening on racket. ^ 1 dwg |
