CROSS-REFERENCE TO RELATED APPLICATIONS
FIELD OF THE INVENTION
This application claims priority from U.S. Provisional Patent Application Ser. No. 60/578,269, filed Jun. 9, 2004.
- BACKGROUND OF THE INVENTION
This invention relates generally to a lacrosse stick, and more particularly to a lacrosse stick having a shaft made of a composite material.
Lacrosse is an established sport which originated with the American and Canadian Indians. Lacrosse sticks were originally made of wood, usually hickory. The original lacrosse sticks were roughly handcrafted and susceptible to the elements. Additionally, the original lacrosse sticks varied greatly in size, shape, and weight because they were made by hand and lacked stringent guidelines.
Conventional lacrosse sticks having a shaft made of wood or metal are known. The metal shafts are usually made using an invariable extruding process. Thus, the shape of the shaft is determined when the extrusion die is manufactured. Further any texture, logos, team colors, etc. must be applied after formation of the shaft by knurling, painting, or another secondary process. Further, a material having a higher strength-to-weight ratio than wood and metal is desired in the art.
U.S. Pat. No. 5,048,843 issued to Dorfi, et al. discloses a lacrosse stick having a head and a handle attached thereto. The head includes a generally V-shaped frame with a crosspiece extending out of the plane of the head. The base of the head includes an arcuate recess along its back side to form with the netting a socket for receiving and retaining the lacrosse ball. The handle is a non-regular octagon in cross-section with the long sides of the handle extending generally parallel to the plane containing the head. The handle is provided at its proximal end with an enlarged butt cap approximately 1.5 times the largest cross-sectional dimension of the handle. The handle also increases in cross-sectional dimension from a median point towards its opposite ends. The netting in the head is replaceable with preformed netting by inserting preformed loops at the ends of the transverse lacing in openings and securing the loops along the outer side frames of the head. The longitudinal reinforcing strips are likewise received in openings and secured in adjusted positions.
U.S. Pat. No. 4,358,117 issued to Deutsch discloses a lacrosse head having grooves along the outer surface of the scoop-shaped end adapted to protect the lacings of a net structure from abrasive contact. The grooves will be defined by grooved depressions in the outer surface of the scoop-shaped end, or pairs of raised ridges on the outer surface of the scoop-shaped end. The grooves will extend from the openings, through which the net structure is laced, to the edge of the frame to which the net is attached.
A lacrosse stick that is stronger and lighter than conventional lacrosse sticks, and has a texture that improves the user's grin would provide further utility.
The invention comprises, in one form thereof, a shaft for a lacrosse stick, including a structural foam core, at least one fabric sleeve surrounding the foam core, and a resin infused into the fabric sleeves. The fabric sleeves consist of woven fibers selected from the group of aramid fibers, carbon fibers, fiberglass, or a combination thereof. A fabric having a personalized pattern applied over the fabric sleeves may be included. Further, a temporary release peel ply material and a temporary plastic mesh may be applied over the fabric sleeves when the epoxy is applied to the shaft.
The invention further comprises a method of making a shaft for a lacrosse stick comprising the steps of: forming a foam core to a desired shape; placing at least one fabric sleeve over said foam core; wrapping a release peel ply material over said at least one fabric sleeve; covering said release peel ply material with a plastic mesh; placing said shaft into a vacuum; infusing said shaft with a resin; curing said shaft; removing said shaft from said vacuum; discarding said plastic mesh; post-curing said shaft; and disposing of said release peel ply material.
BRIEF DESCRIPTION OF THE DRAWINGS
An advantage of the present invention is that the lacrosse stick is stronger and lighter than conventional lacrosse sticks. Further, the lacrosse stick of the present invention has a texture that improves the user's grip. Even further, the lacrosse stick of the present invention provides an integral personalization for the shaft of the lacrosse stick.
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become apparent and be better understood by reference to the following description of the embodiments of the invention in conjunction with the accompanying drawings, wherein:
FIG. 1 is an image of a lacrosse stick of the present invention;
FIG. 2 a is an image showing the layers of the shaft of the present invention;
FIG. 2 b is an image of a partially infused shaft sample;
FIG. 3 a is an image showing the layers of the shaft of the present invention having a personalization layer;
FIG. 3 b is an image of a finished shaft of the present invention having a personalization layer;
FIG. 4 is a an image showing a shaft sample and a vacuum bag prior to infusion; and
FIG. 5 is a cross-sectional view of a hollow shaft according to the second embodiment.
- DETAILED DESCRIPTION
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate several embodiments of the invention but should not be construed as limiting the scope of the invention in any manner.
Referring to FIGS. 1 and 2 a, there is shown the composite shaft for a lacrosse stick of the present invention. The shaft 10 includes a core 12, and an outer casing 14. A head 16 is affixed to one end of the shaft 10.
The core 12, shown in FIG. 2 a, is a structural foam designed for impact such as the foam sold under the name CORE-CELL A 300 by ATC Chemicals Inc. The core 12 is formed to the desired shape of the shaft. This may be accomplished by milling the core 12 to the desired shape. In a particular embodiment of the present invention, the shape of the core 12 may have a consistent cross-section that is round. In additional embodiments of the present invention the core 12 has a consistent cross-section that is polygonal, or the shape may vary to provide a shape that is either ergonomic or that enhances the user's performance.
Prior to processing, the outer casing 14 includes at least one fabric sleeve 20, a release peel ply material 24, and a shade cloth material 26. A particular embodiment of the present invention includes an optional personalization layer 22 (FIG. 3 a). The fabric sleeves 20 may be made of woven aramid fiber (such as KEVLAR), fiberglass, aramid/carbon fiber, or another fabric or paper. The sleeves 20 slide loosely over the core 12. Several layers of sleeves 20 may be used to increase the strength of the shaft 10. For example, most girls lacrosse leagues do not allow checking, therefore a shaft having one layer of a fiberglass sleeve 20 might be used to keep the cost down. However, in a league that does allow checking, several layers of a higher strength material may be required. The personalization layer 22 is a cloth, paper, or plastic containing a logo, a pattern of team colors, a player's uniform number, etc. The personalization layer 22 is applied over the sleeves 20. The release peel ply material 24 is wrapped around the shaft 10 and contributes to the grip of the finished shaft 10. The shade cloth material 26 is a plastic cloth such as those that are conventionally used to provide shade in agricultural applications. The shade cloth material 26 is wrapped around the release peel ply material 24.
After the core 12 and the outer casing 14 are prepared, the shaft 10 is placed into a vacuum bag 28 as shown in FIG. 4. The vacuum bag 28 is then sealed. A vacuum is perfected in the vacuum bag 28 using vacuum tube 29 a and the shaft 12 is infused with a resin 30. The resin 30 is preferably a polymer such as an epoxy, vinyl ester, or urethane. The resin 30 is forced into the vacuum bag 28 via resin tube 29 b. In a particular embodiment of the present invention, approximately between 100 and 150 grams of resin are used to infuse the shafts of the lacrosse sticks. However any amount of resin sufficient to infuse the shafts are within the scope of the invention. In order to deposit resin 30 along the entire length of the shaft 10, the end of the resin tube 29 b is moved along the length of the shaft 10. The shade cloth material 26 provides a conduit for the resin to flow around the shaft 10. As the resin 30 flows through the release peel ply material 24, the weave of the release peel ply material 24 creates a texture in the resin 30 that improves the user's grip on the finished shaft 10.
After the shaft 10 is infused with the resin 30, the vacuum is maintained in the vacuum bag 28 while the shaft 10 cures at room temperature. For particular embodiments of the present invention, it will take approximately 12 hours for the shaft to cure. Once the curing is complete, the shaft 10 is removed from the vacuum bag 28 and the shade cloth material 26 is removed The shaft 10 is post-cured according to the specifications of the manufacturer of the resin 30, for example at an elevated temperature of about 200° F. or higher for approximately 3 hours. The release peel ply material 24 is removed from the shaft 10 and the finished shaft 10 is trimmed to the final size and the head 16 is affixed to one end. The end user may further trim the shaft 10 according to his or her preferences using any appropriate device, such as a conventional saw.
Prior to processing, one end of the core 12 may be milled to a larger diameter than the rest of the shaft 10 in order to mimic the end cap required on hollow shaft lacrosse sticks.
The shaft 10 of the present invention the texture caused by the release peel ply material 24 is integral to the process, not a surface treatment that must be added later. Further, logos, text, color patterns, etc. are added during processing of the shaft 10, not painted on later. This allows for personalization of the shaft 10, such as the shaft shown in FIG. 3 b. Even further, the composite material provides a strong, light shaft 10 that has a low heat transfer coefficient such that the shaft 10 doesn't feel as cold as a metal shaft might in cold weather. Still further, a significant advantage of the shaft 10 is that the shape of the shaft 10 is formed by milling the core 12, not by the shape of a mold. Thus, various shapes and sizes of shaft 10 can be made with little or no changes in manufacturing equipment. Additionally, the cross-sectional shape can vary along the length of the shaft 10 as desired.
Referring now to FIG. 5, an additional embodiment of the present invention is shown. The shaft 110 has a hollow core 112, used in place of the solid core 12. The hollow core 112 is made of a structural foam that is in the shape of a shell. This reduces the amount of material used in the shaft 110, thus shaft 110 is lighter than shaft 10. The shaft 110 is otherwise the same as shaft 10.
While the invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope of the invention.
Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims.