Exercise ball manufacturing method
Provided is a method for manufacturing an exercise ball which is made by using a pasted ball such as a soft leather ball and which has a lower impact value compared to a conventional yarn-wound ball. The exercise ball comprises a spherical hollow rubber bladder ( 2 ) in which compressed air is sealed, and a yarn-wound reinforcement layer ( 3 ) formed by evenly winding a filament yarn around the surface of the rubber bladder, wherein the exercise ball is characterized in that nylon filament yarn, obtained by hard twisting two 30-50 denier nylon filaments 1 - a, 1 - b in a single-direction twist is used as a winding yarn ( 1 ).
1. A sportsball comprising a spherical hollow rubber bladder filled with compressed air and a thread wound reinforced layer formed by evenly winding nylon filament threads around the surface of the rubber bladder, wherein the nylon filament threads each formed by two filament yarns each of 30˜50 deniers with a single twist, are used as winding threads, and each of the twisted nylon filament winding threads has 1800˜2000 T/m twist.
2. A method for manufacturing a sportsball, comprising a spherical hollow rubber bladder filled with compressed air and a thread wound reinforced layer formed by evenly winding nylon filament threads around the surface of the rubber bladder, wherein the nylon filament threads each formed by twisting two filament yarns each of 30˜50 deniers with a single twist, are used as winding threads, and each of the twisted nylon filament winding threads has 1800˜2000 T/m twist,
wherein in forming the thread wound reinforced layer, rubber cement is applied as binder to the winding threads simultaneously with winding the threads around the rubber bladder, in addition, the rubber-cement is sprayed onto the winding threads a little after beginning winding the threads around the bladder, and after finishing of winding the threads and then after the threads are cut, the spraying of rubber cement is further effected to cover the wound threads with the rubber cement, after drying, the thread wound bladder is vulcanized and molded under heat to form a carcass, and natural or synthetic leather panels or expanded sheet panels are bonded onto the surface of the carcass with rubber-based bonding adhesive applied onto the surface of the carcass.