Inner bladder structure for ball

Abstract

A ball inner bladder structure, particularly suitable for a seamless ball, includes a bladder in the form of a spherical bag, a yarn layer enclosing the bladder, an emulsion layer applied over the yarn layer, and a ball cover layer bonded to the emulsion layer. The yarn layer is an integrally knitted web structure having a 3D spherical shape. Knitted yarns subjected to pressure can displace relative to one another to finely adjust a surface configuration of the web structure for the same to completely bear against the bladder. The emulsion layer fills up voids on the yarn layer to provide a smooth spherical surface. The specifically knitted yarn layer can effectively control an expansion degree of the bladder when the same is inflated. And, expansion or compression pressure applied to the bladder is uniformly distributed over interlocking points of knitted yarns, preventing the bladder from deformation and breaking.

1 . An inner bladder structure for ball, particularly suitable for a seamless ball, comprising a bladder being in the form of a spherical bag and forming a main body structure of a seamless ball, a yarn layer being provided on an outer surface of the bladder, an emulsion layer being provided on an outer surface of the yarn layer to serve as a binding material, and a round and smooth ball cover layer bonded to an outer surface of the emulsion layer; the yarn layer being a single-layered web structure integrally knitted using a plurality of yarns to have a three-dimensional (3D) spherical shape with a plurality of voids formed between adjacent knitting yarns; and the emulsion layer filling up the voids on the yarn layer to form a complete spherical body. 
     
     
         2 . The inner bladder structure for ball as claimed in  claim 1 , wherein the web structure of the yarn layer is formed by knitting the yarns around the bladder from a predetermined starting point on the outer surface of the bladder, so that the web structure has a plurality of interlocking points of the yarns and is radially outward expanded from the starting point to gradually increase a winding radius thereof at a fixed spacing; and wherein when the winding radius of the web structure is equal to a radius of the bladder, the knitting continues toward another point on the bladder diametrically opposite to the starting point while the winding radius of the web structure gradually decreases at the same fixed spacing, and when the web structure is finally extended to the diametrically opposite point on the bladder, the spherical-shaped web structure is completed. 
     
     
         3 . The inner bladder structure for ball as claimed in  claim 2 , wherein each of the interlocking points is formed at an intersection of four knitting yarns that are connected to one another at the intersection and extended in four different directions, it is therefore able to control an elongation ratio and expansion degree at the interlocking point when the same is subjected to stress from different directions. 
     
     
         4 . The inner bladder structure for ball as claimed in  claim 1 , wherein the ball cover layer includes an inner filler layer and an outer cover layer; the inner filler layer being in direct contact with and glued to the outer surface of the emulsion layer, and the outer cover layer being formed from a plurality of panels that have the same predetermined shape and are arranged adjoining one another. 
     
     
         5 . The inner bladder structure for ball as claimed in  claim 4 , wherein the outer cover layer is made of thermoplastic polyurethane (TPU), and the inner filler layer is made of ethylene vinyl acetate (EVA). 
     
     
         6 . The inner bladder structure for ball as claimed in  claim 1 , wherein the yarn layer is formed using synthetic twist yarns. 
     
     
         7 . The inner bladder structure for ball as claimed in  claim 1 , wherein the yarn layer is in the form of a spherical-shaped knitted fabric; the spherical-shaped knitted fabric being formed by knitting at a fixed spacing around an axis of a preset spherical surface, which has a radius corresponding to that of the bladder, and the knitting being started from a preset one of the longitudes of the preset spherical surface. 
     
     
         8 . The inner bladder structure for ball as claimed in  claim 7 , wherein the spherical-shaped knitted fabric includes a plurality of knitting yarns, which are repeatedly bent to form a plurality of loop portions; the loop portions being respectively extended through a loop portion formed by a previous adjacent knitting yarn, and then being respectively extended through by another loop portion formed by a next adjacent knitting yarn, so that a web structure is formed with a void formed in each loop portion and between any two laterally adjacent loop portions. 
     
     
         9 . The inner bladder structure for ball as claimed in  claim 7 , wherein the ball cover layer includes a filler layer and an outer cover layer; the filler layer being in direct contact and glued to the outer surface of the emulsion layer, and the outer cover layer being formed from a plurality of panels that have the same predetermined shape and are arranged adjoining one another. 
     
     
         10 . The inner bladder structure for ball as claimed in  claim 9 , wherein the outer cover layer is made of thermoplastic polyurethane (TPU), and the filler layer is made of ethylene vinyl acetate (EVA). 
     
     
         11 . The inner bladder structure for ball as claimed in  claim 7 , wherein the yarn layer is formed using synthetic twist yarns.