Training balls for varying ball speed, methods of use, and systems

Abstract

Methods and apparatus provide for at least one ball, comprising: a hard shell of a predetermined size defining an internal volume and including a plurality of apertures therethrough; and a foam core disposed within the internal volume.

1 . A ball, comprising:
 a hard shell of a predetermined size defining an internal volume and including a plurality of apertures therethrough; and   a foam core disposed within the internal volume.   
   
   
       2 . The ball of  claim 1 , wherein a diameter of the foam core is less than a diameter of the internal volume such that a layer of air is located between an outside surface of the foam core and an inside surface of the hard shell. 
   
   
       3 . The ball of  claim 2 , wherein the foam core fills the internal volume. 
   
   
       4 . The ball of  claim 2 , further comprising at least one spacer disposed between the outside surface of the foam core and the inside surface of the hard shell, and adapted to position the foam core within the internal volume. 
   
   
       5 . The ball of  claim 4 , wherein the at least one spacer is adapted to connect the outside surface of the foam core to the inside surface of the hard shell. 
   
   
       6 . The ball of  claim 5 , wherein at least one of: the at least one spacer is formed of the core material, and the at least one spacer is integrally formed with the foam core. 
   
   
       7 . The ball of  claim 4 , wherein a size and shape of the at least one spacer is operable to accommodate different distances from the inside surface of the hard shell to the outside surface of the foam core, such that the diameter of the foam core may be increased or decreased relative to the diameter of the hard shell. 
   
   
       8 . The ball of  claim 1 , wherein a composition of the foam core is taken from the group consisting of: nylon, acetal, teflon, polycarbonate, acrylic, polyurethane blend, polyethylene, polystyrene, urethane, polyester, polypropylene, neoprene, rubber cork, black nitrile, silicone, plastic, hyplon, fluorocarbons, ethylene propylene diene monomer rubber, elastomer, ceramic, acetate, urea, polymethylpentene, acrylonitrile butadiene styrene, polyetheretherketone, and polyvinyl chloride. 
   
   
       9 . The ball of  claim 1 , wherein at least one of a porosity and a composition of the foam core are predetermined for a desired density. 
   
   
       10 . The ball of  claim 9 , wherein the foam core includes an inner portion having a first density and an outer portion having a second density surrounding the inner portion. 
   
   
       11 . The ball of  claim 10 , wherein at least one of:
 the first density is substantially higher than the second density;   the inner portion is not formed of foam; and   the outer portion is formed of foam.   
   
   
       12 . The ball of  claim 9 , wherein the density affects at least one aerodynamic characteristic of the ball. 
   
   
       13 . The ball of  claim 9 , wherein the density of the foam core is related to a speed at which the ball travels through air when released at a predetermined velocity. 
   
   
       14 . The ball of  claim 12 , wherein the density is linearly related to the speed. 
   
   
       15 . The ball of  claim 9 , wherein the density of the foam core is at least one of: 1 to 300 kg/m 3 , 1 to 100 kg/m 3 , 1 to 10 kg/m 3 , 1 to 5 kg/m 3 , 5 to 10 kg/m 3 , 10 to 30 kg/m 3 , and 15 to 20 kg/m 3 . 
   
   
       16 . The ball of  claim 9 , wherein
 a diameter of the foam core is less than a diameter of the internal volume such that a layer of air is located between an outside surface of the foam core and an inside surface of the hard shell; and   a volume of the layer of air is inversely related to a speed at which the ball travels through air when released at a predetermined velocity.   
   
   
       17 . The ball of  claim 1 , wherein the size of the hard shell is a size of one of: a ping pong ball, a golf ball, a baseball, a softball, a tennis ball, a polo ball, a rugby ball, a football, a soccer ball, a volley ball, a racquet ball, and a hand ball. 
   
   
       18 . A method for teaching a person to hit a ball, comprising:
 providing a plurality of balls, each ball comprising: (i) a hard shell defining an internal volume and including a plurality of apertures therethrough, and (ii) a foam core disposed within the internal volume; and   propelling the balls toward the person by releasing them, in turn, at a substantially constant velocity.   
   
   
       19 . The method of  claim 18 , wherein the foam core of at least one of the balls has a density substantially different than the foam core of at least one other of the balls, such that the balls travel through air at different speeds despite being released at the substantially constant velocity. 
   
   
       20 . The method of  claim 19 , wherein the difference between the density of the foam core of the at least one of the balls and the density of the foam core of the at least one other of the balls is such that the balls travel through the air at speeds differing by at least about 10%. 
   
   
       21 . The method of  claim 20 , wherein the difference in density is such that the balls travel through the air at speeds differing by at least about 5% to about 20%. 
   
   
       22 . The method of  claim 18 , wherein:
 a diameter of the foam core of at least one of the balls is less than a diameter of the internal volume thereof such that a layer of air is located between an outside surface of the foam core and an inside surface of the hard shell; and   a volume of the layer of air is such that the at least one of the balls and at least one other of the balls travel through air at different speeds despite being released at the substantially constant velocity.   
   
   
       23 . The method of  claim 22 , wherein the volume of air within the at least one of the balls is such that the balls travel through the air at speeds differing by at least about 10%. 
   
   
       24 . The method of  claim 22 , wherein the volume of air within the at least one of the balls is such that the balls travel through the air at speeds differing by at least about 5% to about 20%. 
   
   
       25 . The method of  claim 18 , wherein a plurality of the balls have substantially equal size. 
   
   
       26 . The method of  claim 18 , wherein a deviation of the size is one of: no greater than about 5%, no greater than about 2%, and no greater than about 1%. 
   
   
       27 . The method of  claim 18 , wherein the step of propelling the balls at the substantially constant velocity is carried out manually. 
   
   
       28 . The method of  claim 18 , wherein the step of propelling the balls at the substantially constant velocity is carried out by an automated machine. 
   
   
       29 . A system, comprising:
 a plurality of balls, each ball comprising: (i) a hard shell defining an internal volume and including a plurality of apertures therethrough; and (ii) a foam core disposed within the internal volume,   wherein the foam core of at least one of the plurality of balls is adapted to cause such ball to travel through air at a substantially different speed as compared to at least one other of the plurality of balls despite the balls being released at a substantially constant velocity.   
   
   
       30 . The system of  claim 29 , wherein at least one of:
 at least one of the plurality of balls includes a foam core that fills the internal volume thereof; and   at least one of the plurality of balls includes at least one spacer disposed between the outside surface of the foam core thereof and the inside surface of the hard shell thereof, the at least one spacer being adapted to position the foam core within the internal volume.   
   
   
       31 . The system of  claim 30 , wherein the at least one spacer is adapted to connect the outside surface of the foam core to the inside surface of the hard shell. 
   
   
       32 . The system of  claim 29 , wherein
 at least some of the plurality of balls include respective foam cores having respective porosities and/or compositions that are predetermined to achieve different respective densities; and   the difference in density among the foam cores of the at least some of the plurality of balls are such that the balls travel through air at substantially different speeds despite being released at a substantially constant velocity.   
   
   
       33 . The system of  claim 32 , wherein the foam cores of the at least some of the plurality of balls are such that the balls travel through the air at speeds differing by at least about 5% to about 20%. 
   
   
       34 . The system of  claim 29 , wherein:
 at least some of the plurality of balls include respective foam cores having diameters that are less than diameters of the internal volumes such that respective layers of air are located between outside surfaces of the foam cores and inside surfaces of the respective hard shells; and   respective volumes of the layers of air of the at least some of the plurality of balls are such that the balls travel through air at different speeds despite being released at the substantially constant velocity.   
   
   
       35 . The system of  claim 34 , wherein the respective volumes of the layers of air within the at least some of the plurality of balls are such that the balls travel through the air at speeds differing by at least about 10%. 
   
   
       36 . The system of  claim 29 , wherein the plurality of balls have substantially equal size.