Bat system with performance limiting structure and methods of making same

Abstract

The disclosed technology includes bat comprising a first hollow barrel, a second hollow barrel disposed in the first hollow barrel and spaced a distance apart from the first hollow barrel, and a compressible material disposed between the first hollow barrel and the second hollow barrel. The disclosed technology further includes a bat, which has a hollow barrel and an internal assembly configured to resist deformation of the hollow barrel. The internal assembly includes a rod disposed longitudinally in the hollow barrel, a ring attached to the rod, a deformable sleeve (a second hollow barrel) disposed around the ring and extending longitudinally in the hollow barrel. The bat can include a compressible material disposed between the hollow barrel and the deformable sleeve.

What is claimed is: 
     
         1 . A bat comprising:
 a first hollow barrel;   a second hollow barrel disposed in the first hollow barrel and spaced a distance apart from the first hollow barrel; and   a compressible material disposed between the first hollow barrel and the second hollow barrel.   
     
     
         2 . The bat of  claim 1 , wherein responsive to receiving force from an impact with an object, the first hollow barrel is configured to flex inwardly such that an inner surface of the first hollow barrel compresses the compressible material against the second hollow barrel. 
     
     
         3 . The bat of  claim 2 , wherein the compressible material is further configured to transfer a rebound force to the first hollow barrel as the compressible material returns from a deformed shape to an original shape. 
     
     
         4 . The bat of  claim 2 , wherein:
 the first hollow barrel is configured to transfer at least some of the force from the impact to the second hollow barrel via the compressible material, and   the second hollow barrel is configured to:
 at least partially deform from an original shape to a deformed shaped upon receiving the at least some of the force from the impact; and 
 return from the deformed shape to the original shape. 
   
     
     
         5 . The bat of  claim 4 , wherein the second hollow barrel is further configured to transfer a rebound force to the first hollow barrel as the second hollow barrel returns from the deformed shape to the original shape. 
     
     
         6 . The bat of  claim 1 , wherein the compressible material extends along less than an entire length of the second hollow barrel. 
     
     
         7 . The bat of  claim 1 , wherein the compressible material comprises a first portion and a second portion, the first portion being positioned proximally and the second portion being positioned distally along the second hollow barrel. 
     
     
         8 . The bat of  claim 1 , wherein the compressible material is disposed at approximately a middle portion of the second hollow barrel and extends proximally and distally. 
     
     
         9 . The bat of  claim 8 , wherein the compressible material extends approximately less than half of a length of the second hollow barrel. 
     
     
         10 . The bat of  claim 8 , wherein the compressible material extends approximately less than one third the length of the second hollow barrel. 
     
     
         11 . The bat of  claim 1 , wherein the compressible material has a density of between 0.35 g/cm 3  to about 0.4 g/cm 3 . 
     
     
         12 . The bat of  claim 1 , wherein the compressible material has a Shore A hardness of about 40 to about 50. 
     
     
         13 . The bat of  claim 1 , wherein the compressible material comprises polyurethan foam. 
     
     
         14 . The bat of  claim 1  further comprising:
 a rod disposed longitudinally in the first hollow barrel and second hollow barrel; 
 a ring attached to the rod and disposed at least partially in the second hollow barrel; and 
 an end cap attached to an end of the first hollow barrel, the end cap having a recess configured to receive an end of the rod, 
 wherein the rod is configured to maintain the second hollow barrel in a predetermined suspended position within the first hollow barrel such that, when the bat is at rest, the second hollow barrel is disposed a predetermined gap distance from an inner surface of the first hollow barrel. 
 
     
     
         15 . The bat of  claim 14  further comprising an alignment insert comprising:
 an outer diameter approximately equal to an inner diameter of the first hollow barrel; and 
 a lobe configured to receive a portion of the rod. 
 
     
     
         16 . A bat comprising:
 an outer barrel;   an inner barrel disposed in the outer barrel and spaced a distance apart from the outer barrel; and   a compressible material disposed between the outer barrel and the inner barrel and extending along the inner barrel a distance less than half of a length of the inner barrel.   
     
     
         17 . The bat of  claim 16 , wherein the compressible material comprises a first portion and a second portion, the first portion being positioned proximally and the second portion being positioned distally along the inner barrel. 
     
     
         18 . The bat of  claim 16 , wherein the compressible material is disposed at approximately a middle portion of the inner barrel and extends proximally and distally. 
     
     
         19 . The bat of  claim 16 , wherein the compressible material has a density of between 0.35 g/cm 3  to about 0.4 g/cm 3 . 
     
     
         20 . The bat of  claim 16 , wherein the compressible material has a Shore A hardness of about 40 to about 50.