Patent Publication Number: US-2005124441-A1

Title: Spiral wound laminate wood and method for construction

Description:
REFERENCE TO RELATED APPLICATION  
      This application claims the benefit of U.S. Provisional Application No. 60/462,086, filed Jun. 23, 2003, entitled “Spiral Wound Laminate Wood and Method for Construction,” incorporated herein by reference. 
    
    
     TECHNICAL FIELD OF THE INVENTION  
      The present invention relates to wood products, and more particularly to  
     BACKGROUND OF THE INVENTION  
      Baseball bats made of a single piece of wood are susceptible to breakage and contain a weaker and stronger plane based upon the orientation of the wood grain. Other attempts to construct laminated wooden bats resulted in the same preferred strength orientation depending upon the coarseness or orientation of the laminates. Frequently these bats fracture when a ball is hit perpendicular to the glue plane. Construction using fiberglass reinforced plastic (FRP) or other materials alters the feel and density of the bat.  
      Spiral wound veneer construction eliminates all of these problems by providing a bat of primarily all wood construction with a density and mass virtually identical to the native material but superior in strength. The strength of the spiral laminates is identical from all sides because the grain strength and orientation are along the axis of the bat. The bat therefore cannot be struck at an angle that is parallel to the glue line, thereby making the bat extremely difficult to break. No longer will hitters have to be careful to orient the bat with the label facing in a preferred orientation to prevent accidental breakage. This construction will allow a player to hit the ball at any location because there is no weaker orientation.  
      The spiral construction allows for a bat that is uniform in both feel and performance. The construction, since it is extremely strong in all directions, will be very resistant to breakage and safer for both players and spectators alike. Since veneer construction is an extremely efficient wood utilization process it will serve to preserve the natural resources through higher wood utilization.  
     SUMMARY OF THE INVENTION  
      The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.  
      This invention is for a primarily wood laminated bat that is constructed of a continuous wound piece of veneer wood. The bat is laminated by rolling a thin piece of wood veneer into a very tight spiral roll. The veneer is glued to itself by way of a common glue, epoxy, or thermal-set resin. The process is performed in one, two, or more steps, increasing the roll diameter in each step, to approximate the final shape of the finished bat or product.  
      In order to compress the wood veneer into a tightly wound cylindrical cone shape, it is necessary to press the rolled assembly into a tapered die with a hydraulic or pneumatic cylinder. Other mechanical devices such as a lead screw can also be used to force the veneer into the tapered mold while the resin sets. This is done to eliminate the air voids and to minimize the glue thickness between the layers of wood to create the strongest bond. Once the glue, epoxy, or resin has cured, the spiral-wound laminated core is removed from the tapered die.  
      This process is repeated in a second or third step where additional thicker veneer material is wrapped around the previously cured core of spirally-wrapped veneer to build it up to the approximate final size and shape. In these subsequent steps the veneer is coated in resin, glue, or epoxy and forced into a larger tapered die in much the same way as the original core was constructed. However, in the subsequent steps, the inner cured core is used as a tapered wedge to compress the outer veneer wrap against the outer tapered wall of the mold to a compression level just below the yield of the cellulose material of the outer veneer.  
      The veneer material is cut from a conveniently sized piece of material so that the final roll is already slightly tapered.  
      The slightly tapered die provides an ideal shape to create tremendous circumferential forces on the spiral laminate. This can be done with a very low axial force on the roll due to the great advantage of the slightly tapered mold. The large circumferential force created by the mold will eliminate air bubbles in the glue or binder and will serve to minimize glue thickness, thereby creating an extremely strong laminate bond.  
      The spiral wound bat is extremely strong and has no preferred orientation of maximum strength. It can be hit from any angle, orientation, or direction without shattering and breaking. A continuously wound spiral pattern from the core of the bat to the outer surface results in a wood laminate that has exceptional strength and is uniform in all directions. Players will not have to be worried about a preferred grain orientation when using this bat as they do with conventional bats or other laminated bats.  
      Other features of this bat construction and method are as follows: 
          Extremely durable.     Stronger than base wood.     Uniform balance.     Density is similar to the original material by matching the parent wood with the veneer laminate.     No need to consider wood grain orientation when using the bat.     Omni directional strength.     Safety.     Strong wooden bat.     Best/largest sweet spot.     Less vibration on hands.        

      Can modify grain alignment to modify characteristics by rolling veneer at an angle as opposed to normal to the grain structure.  
      Other features of the invention will become apparent from the following detailed description when taken in conjunction with the drawings, in which:  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  shows the end of view, from the top, of a bat with a single veneer laminate sheet in spiral configuration from the center of the bat to the outer most surface.  
       FIG. 2  shows the side view of the spiral wound laminate bat shown in  FIG. 1  after final shaping on a lathe or other turning device.  
       FIG. 3  shows the end of view, from the top, of a bat with multiple (2) veneer laminate sheets in spiral configuration. The first veneer sheet is wound clockwise from the center out and the second veneer sheet is wound counter clockwise from the center out.  
       FIG. 4  shows the side view of the spiral wound laminate bat depicted in  FIG. 3 .  
       FIG. 5  shows a side cutaway view of a hydraulic press and tapered mold device for pressing the spiral wound veneer laminate into a tight coil for curing.  
       FIG. 6  shows a side cutaway view of a hydraulic press and tapered mold device for pressing a second spiral wound veneer laminate into a tight coil around the first spiral wound laminate.  
       FIG. 7  shows a plan view of a piece of veneer that has been cut on one corner to result in a tapered roll when rolled into a tight spiral.  
       FIG. 8  shows the resultant tapered roll created by the veneer that has been cut to create a taper.  
    
    
     DETAILED DESCRIPTION  
      In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described.  
      The spiral wound bat or other implement will be constructed of either a single or multiple veneer sheet(s)  22  of varying thicknesses wound in a very tight spiral pattern  14  as illustrated in  FIGS. 7 and 8 . For ease of description, one sheet will be referenced throughout this disclosure. The veneer sheet can be cut at an angle  22  to create a slightly tapered profile  21  when rolled. The veneer sheet is then coated with a common glue, binder, epoxy or thermal set resin, rolled  14 , and placed into a tapered mold  13  as shown in  FIG. 5 .  
      The rolled and glue coated veneer  14  is forced into a tapered mold  13  by a hydraulic cylinder  10  with ram  11  and tapered end  12 . The hydraulic ram is actuated and forces the spirally-wound veneer  14  into the tapered mold  13 . The mold  13  creates an extremely high circumferential force upon the roll thereby eliminating any air bubbles or large pockets of glue. This high force also creates a very high strength bond joint between the subsequent layers of wood veneer. Once cured, the laminated piece  14  is removed from the mold  13 .  
      The first spiral wound laminate  14  serves as the core  14  for a second spiral wound laminate  20 . This veneer  22  of the same or thicker material is coated with glue, epoxy, or thermal cure resin and spiral wound around the outside of the core  14 . This assembly is placed into a gradually tapered mold  18 . The outer veneer  20  is held in place while the inner cured core  14  is forced by the hydraulic ram  11  into the mold  18  thereby compressing the outer veneer  22  against the tapered mold. The mold  18  and tapered core  14 , due to their tapered design, create extremely high circumferential forces onto the spiral wound wood veneer  20 . These high forces are maintained below the crush threshold of the cellular veneer material to create a very strong bond without any air pockets.  
      The bat  7  is shaped by turning or machining to the final desired shape and balance which includes the barrel  7 , handle  8  and knob  9  as shown in  FIG. 2 . All sections of the bat  6  include spiral laminates resulting in maximum strength in all directions. The bat can also be made in multiple stages using multiple laminates as shown in  FIGS. 3 and 4 .  
      Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, a certain illustrated embodiment thereof is shown in the drawings and has been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.  
      All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.  
      The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.  
      Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.