SPORTING IMPLEMENT FORMED WITH A MELT-PROCESSABLE STRUCTURAL BINDER
A composite sporting implement, such as a ball bat or bat barrel, is formed with layers of continuous structural fibers embedded in a binder material having a high melting point. Such a binder does not undergo a chemical conversion process during forming of the ball bat. The layers are shaped into a preform and placed in a mold. Heat and pressure are applied to bring the binder to its melting point and to cause the binder material to flow between adjacent layers. The mold is then cooled below the binder's melting point to solidify the composite structure. A composite sporting implement formed in this manner exhibits excellent shear strength, toughness, and damping qualities.
1 . A method of making a bat barrel, comprising the steps of:
providing a plurality of layers comprising continuous structural fibers in a binder having a melting point greater than 400° F.;
forming the layers into a barrel preform;
positioning the barrel preform in a mold;
heating the barrel preform in the mold to a temperature sufficient to bring the binder to its melting point so that the binder flows between adjacent layers;
cooling the binder in the mold below its melting point to bond the layers to one another to form a barrel structure; and
removing the barrel structure from the mold.
2 . The method of claim 1 further comprising the step of forming the layers into a handle preform that is integral with the barrel preform before positioning the barrel preform in the mold, such that a ball bat including a barrel and an integral handle is formed during the cooling step.
3 . The method of claim 1 further comprising the step of pressurizing the mold during the heating and cooling steps.
4 . The method of claim 1 wherein the binder does not undergo a chemical conversion process during the heating and cooling steps.
5 . A ball bat, comprising:
a handle;
a barrel integral with or attached to the handle, wherein the barrel comprises a plurality of layers of continuous structural fibers bonded to one another by a binder having a melting point greater than 400° F.
6 . The ball bat of claim 5 wherein the binder has a melting point between 400 and 450° F.
7 . The ball bat of claim 5 wherein the binder has a melting point between 500 and 550° F.
8 . The ball bat of claim 5 wherein the binder has a melting point between 600 and 650° F.
9 . The ball bat of claim 5 wherein the continuous fibers are unidirectional.
10 . A sports implement, comprising:
a tubular body comprising a plurality of layers of continuous, unidirectional fibers bonded to one another by a binder having a melting point greater than 400° F.
11 . The sports implement of claim 10 wherein the tubular body is in the form of a lacrosse stick shaft.
12 . The sports implement of claim 10 wherein the tubular body is in the form of a hockey stick shaft.
13 . The sports implement of claim 10 wherein the tubular body is in the form of a bicycle frame component.
14 . The ball bat of claim 10 wherein the binder has a melting point between 400 and 450° F.
15 . The ball bat of claim 10 wherein the binder has a melting point between 500 and 550° F.
16 . The ball bat of claim 10 wherein the binder has a melting point between 600 and 650° F.
17 . The ball bat of claim 10 wherein the continuous fibers are unidirectional.
18 . A method of making a sporting implement, comprising the steps of:
providing a plurality of layers comprising continuous structural fibers in a binder having a melting point greater than 400° F.;
forming the layers into a preform;
positioning the preform in a mold;
heating the preform in the mold to a temperature sufficient to bring the binder to its melting point so that the binder flows between adjacent layers;
cooling the binder in the mold below its melting point to bond the layers to one another to form a sporting implement; and
removing the sporting implement from the mold.
19 . The method of claim 18 further comprising the step of pressurizing the mold during the heating and cooling steps.
20 . The method of claim 18 wherein the binder does not undergo a chemical conversion process during the heating and cooling steps.