Patent Publication Number: US-2015065278-A1

Title: Multi-component bat and assembly process

Description:
BACKGROUND OF THE INVENTION 
     The present invention generally relates to baseball and softball bats. More particularly, the present invention relates to a bat of multiple components which are quickly and easily assembled to one another. 
     Baseball and softball are very popular sports in the United States and many other countries. Due to the competitive nature of these sports, players are constantly seeking ways of improving their performance. An important aspect of baseball and softball is the ability to effectively hit the ball. 
     In the past, all bats were made of wood. In fact, at the professional baseball level only wood bats are used. However, wood bats have disadvantages, including the fact that they can break and splinter. This can present a significant cost to individuals and teams at the amateur level. 
     Metal, typically aluminum, bats are allowed in baseball amateur play from Little League to college levels. Metal bats are also typically used in slow and fast pitch softball. Metal bats are advantageous over wood bats in that they do not break and splinter like wood bats, and thus can be used repeatedly with consequent cost savings. Metal bats can also have a larger optimal hitting area or power zone, sometimes referred to as the “sweet spot”, than wood bats. 
     An early approach to manufacturing metal bats is disclosed by U.S. Pat. No. 1,611,858 to Middlekauff, wherein the bat was made from tapered steel tube, formed by a rolled tapered sheet with mating edges joined along a seam to form the tube. However, it soon became apparent that seamless lightweight metal tubing, such as aluminum or titanium, was preferred. This is due to the fact that the metal bat should closely resemble the operating characteristics of a wood bat, so as to exhibit the weight distribution, feel, and sound of the wood bat when hitting the ball. 
     Early efforts to develop aluminum bats included the approach of swaging down the length of a cylindrical extrusion or tube. The extrusion is swaged down by striking or contacting the member with clapping hammers, which repetitively strike the outer surface of the extrusion. The striking motion is perpendicular to the longitudinal axis of the tube, which causes the exterior diameter of the tube to be reduced, thus forming an intermediate tapered portion and handle end of the bat. 
     While generally having a smooth outer surface, it was discovered that the interior surface of the bat formed by this method was less than smooth and could have cracks or fractures running parallel to the longitudinal axis of the bat. Of course, these cracks weakened the bat and reduced its longevity. Moreover, the swaging process did not result in a uniform wall thickness of the tapered section. Moreover, the increased wall thickness added to the weight of the bat and did not contribute to the strength of the bat as it displaced the center of gravity of the bat away from the hitting end of the bat. 
     In an effort to overcome these disadvantages, a methodology of forming a hollow metal bat using a cold pilger process was devised, such as described in U.S. Pat. No. 5,626,050 to Ploughe et al. In accordance with this methodology, an aluminum tube blank was fixed into a “pusher” having a cylindrical opening with a diameter slightly larger than the outer diameter of the tube blank. The pusher and a threaded extension rod were used to advance the aluminum tube blank into a pilger mill, also referred to as a reducing rolling mill. This reduced the aluminum tube to form the handle section and the tapered section, and thereby formed the bat-shaped stock for fabricating a hollow metal bat. 
     However, this procedure also had its disadvantages. The use of an adapter, a pusher, and a threaded extension rod were found to be unsafe, inefficient and time-consuming. This process also used a partial, typically half ring die set, which generated a significant amount of heat when reducing the tubes. Although the use of an internal mandrel was useful to control the tube wall thickening as compared to the swaging process, it significantly added to the metal working costs and greatly increased the stress in the machinery used to reduce the outside diameter of the tube. 
     Subsequently, a drawn process, such as disclosed in U.S. Pat. No. 6,735,998 to Mitchell, was conceived in order to form metal bats. A blank was drawn only partly through a contoured die or a succession of dies. By only reducing the diameter of essentially only a select length of the tubular metal blank by the use of tension applied to pull the metal blank in a die or succession of dies, Mitchell asserted that an intermediate annealing step could usually be eliminated and a thinner tube wall and the handle and transition section of the bat obtained. 
     Yet later, it was discovered that each of the swaging, cold pilgering, and draw processes presented both advantages as well as disadvantages, however, a combination of these processes could be used to synergistically create a better bat and an improved manufacturing process. This combination of processes is disclosed in U.S. Pat. No. 7,328,599 to Van Nguyen. 
     Notwithstanding the advances in manufacturing metal bats, these metal bats have certain disadvantages, including vibrating upon impact and sending painful vibrations into the hands and arms of the batter if the ball is not within the “sweet spot” of the bat. Metal bats also emit an undesirable high-pitch metallic sound, as opposed to the traditional sound heard when a wood bat contacts the ball. 
     Various attempts have been made to overcome the problems associated with metal bats, including coating or wrapping the exterior of the metal bat with material, such as carbon reinforcing fibers, to enhance batting performance. Other attempts have been made to insert internal layers or compartments within the metal bat to improve performance. Bats that incorporate composite materials tend to be much lighter than metal bats. However, while providing benefits, these designs also have drawbacks in that they can be expensive and difficult to manufacture and are prone to structural failure. 
     Notwithstanding the disadvantages of metal and composite bats, these bats are very popular at the amateur level as not only can they be used repeatedly with consequent cost savings, they also have a larger “sweet spot” hitting area or power zone than wood bats. Furthermore, the ball comes off a metal bat faster than a wood bat, resulting in longer hits. 
     In fact, over the years there have been many injuries and near misses attributed to the speed from which a ball comes off a metal and/or composite bat. Several years ago, the National Collegiate Athletic Association (NCAA) for college and the National Federal of High School Association (NFHS) for high school baseball began to regulate batted-ball speeds of baseball bats indirectly by regulating the Ball Exit Speed Ratio (BESR) and controlling bat swing speed by limiting the moment-of-inertia (MOI) of non-wood baseball bats. More recently, the NCAA and NFHS replaced the previous BESR standard with a Bat Standard, or the Batted-Ball Coefficient of Restitution, sometimes referred to as Bat-Ball Coefficient of Restitution (BBCOR). Instead of measuring the speed of the ball after it is batted, BBCOR measures the “bounciness” of the ball and bat or the “trampoline” effect. The new standard ensures that performances by non-wood bats are more comparable to those of wood bats. In order to meet the standard, the BBCOR must be less than or equal to 0.500. 
     With the new standards, the non-wood bats, typically the multi-component metal and composite bats, have been modified. A multi-component bat of both metal, typically aluminum or aluminum alloy, and a composite material created complicated manufacturing and assembling processes. The new standards have not lessened the complication of the manufacturing and assembly of these multi-component bats. Of course, the complicated nature of the manufacturing and assembly of the bat increases the expense of the bat, or reduces the profit made from the bat. 
     Accordingly, there is a continuing need for a baseball or softball bat which has the advantages of a multi-component bat. What is also needed is a baseball or softball bat capable of meeting the regulation requirements for Little League, Amateur Softball Association of America (ASA), National Softball Association (NSA), United States Specialty Sports Association (USSSA), Independent Softball Association (ISA), International Softball Federation (ISF), NFHS, and NCAA. What is further needed is a baseball or softball bat which is relatively simple to manufacture and assemble. The present invention fulfills these needs and provides other related advantages. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a baseball or softball bat. The bat is manufactured by providing an elongated handle having an interconnection member at one end. Typically, an end of the handle is inserted into an opening of the interconnecting member. An aperture of the interconnecting member is aligned with an aperture of the handle, and a pin is inserted through the aligned apertures. 
     The handle is inserted through a generally cylindrical bat barrel to position the interconnection member within the bat barrel, with the remainder of the handle extending outwardly from the bat barrel. The interconnection member is attached to the barrel. Typically, the interconnection member is threadedly attached to the bat barrel, such as by turning the interconnection member relative to the bat barrel to engage threads of the interconnecting member and a connection region of the bat barrel to attach the interconnecting member and handle to the bat barrel. 
     An end cap is attached to a first open end of the bat barrel. A knob and a grip is associated with the handle. For example, a sheath may be attached over at least a portion of the handle, the sheath defining a grip and a knob at an end thereof. 
     The present invention is also directed to a process for assembling a baseball or a softball bat. A bat barrel is provided having a first open end, a second open end generally opposite the first open end and an inner connection region adjacent to the second open end. A handle is provided having a first end, a second generally opposite end and an interconnecting member disposed adjacent to the first end. At least a portion of the interconnecting member has an outer surface configuration corresponding to the connection region of the bat barrel. The second end of the handle is inserted into the first open end of the bat barrel. The second end of the handle is passed through the second open end of the bat barrel until the interconnecting member is disposed at the connection region of the bat barrel. The interconnecting member is attached to the connection region of the bat barrel. 
     Typically, the interconnection region of the bat barrel is threaded, as is an outer surface of the interconnection member. The attaching step comprises threadedly interconnecting the handle to the bat barrel. 
     The handle is locked to the bat barrel. The first end of the handle is inserted into an opening of the interconnecting member and attached thereto. In one embodiment, an aperture of the interconnecting member is aligned with an aperture of the handle, and a pin is inserted through the aligned apertures. 
     An end cap is attached to an open end of the bat barrel, and a knob and a grip are associated with the handle. For example, a sheath may be attached over at least a portion of the handle, the sheath defining a grip and a knob at an end thereof. 
     Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings illustrate the invention. In such drawings: 
         FIG. 1  is a side view of a bat embodying the present invention; 
         FIG. 2  is an exploded perspective view of components of the bat of the present invention; 
         FIG. 3  is an enlarged perspective view of a handle and interconnecting member, used in accordance with the present invention; 
         FIG. 4  is a cross-sectional view taken generally along line  4 - 4  of  FIG. 1 ; 
         FIG. 5  is an enlarged cross-sectional view of area “5” of  FIG. 4 , illustrating the attachment of an interconnection member to a bat barrel of the bat, in accordance with the present invention; 
         FIG. 6  is an enlarged cross-sectional view of area “6” of  FIG. 4 , illustrating the attachment of an end cap to the bat barrel; 
         FIG. 7  is a perspective view of a knob used in accordance with the present invention; and 
         FIG. 8  is a cross-sectional view illustrating the knob of  FIG. 7  attached to the handle of the bat. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is directed to a bat, as shown in the accompanying drawings for purposes of illustration. The bat typically comprises a baseball or softball bat, but can comprise any bat intended for hitting a ball. More particularly, the present invention is directed to a process for manufacturing and assembling a bat which is quick, easy and relatively inexpensive, while still maintaining the advantages found in multi-component bats. 
     With reference now to  FIG. 1 , an assembled bat  10  embodying the present invention is shown. As shown in  FIG. 2 , the bat  10  is generally comprised of a bat barrel  12 , a handle  14 , and an interconnecting member  16  attached to an end of the handle  14 . As will be more fully described herein, the interconnecting member  16  is attached to an end of the handle  14 , and the handle  14  is drawn through first and second open ends  18  and  20  of the bat barrel  12  until the interconnecting member  16  is disposed within the bat barrel, such as at an inner connection region  22  of the bat barrel  12 . The bat barrel  12  and the interconnecting member  16  are attached to one another, effectively attaching the handle  14  to the bat barrel  12 . 
     The bat barrel  12  is preferably formed of a strong material, such as an aluminum alloy. Alternatively, other materials can be used such as a titanium alloy, a scandium alloy, steel, a composite material, a thermal plastic material, a thermo set material, wood and combinations thereof. Typically, however, the bat barrel  12  is comprised of a metal, such as aluminum or an aluminum alloy. The bat barrel  12 , and the assembled bat  10 , is also preferably manufactured so as meet the NCAA and NFHS Rules Committee bat standards, such as the BBCOR standard, which is currently a maximum value of 0.500. 
     When the bat barrel  12  is comprised of aluminum, or another metal alloy, the bat barrel  12  may be manufactured in accordance with the following steps. A cylindrical hollow tube of raw material is annealed as needed to remove all residual stresses. The tubes are formed through a pilger to a smaller outer diameter and thinner wall thickness. The tubes are then cleaned and re-annealed. The tubes are drawn through a die and over a mandrel to a desired outer diameter and wall thickness. The tubes are then cut into a predetermined length, and chemically cleaned. 
     The tube shells are then drawn to a specified variable wall design. The tube shells are then chemically cleaned. The tubes are then drawn again to obtain precision of the outer diameter and wall thickness, and chemically cleaned again. The drawn tube shells are then heat treated and artificially aged to a desired temper, such as a T6 temper. The shell is cut to a preset length, as required per the specification of the bat design. The tube shells are then CNC drawn to meet final required specifications, after which the tube shells are chemically treated and finished. 
     As can be seen in the various drawings, the bat barrel  12  includes a generally cylindrical upper portion  24 , and a generally tapered or frustoconical lower section  26  adjacent to the second open end  20 . The inner connection region  22  of the bat barrel is typically defined by an inner surface of this lower tapered section  26 . Typically, the inner connection region  22  is adjacent to the second open end  20 , as shown in  FIGS. 4 and 5 . 
     The interconnecting member  16  is sized and configured so as to pass through the first open end  18  of the bat barrel and into the bat barrel  12  until it is disposed at the inner connection region  22  of the bat barrel  12 . Preferably, the interconnecting member  16  has an outer surface configuration substantially matching the inner surface configuration of the inner connection region  22 . As such, the interconnecting member  16  is typically generally conical in configuration so as to nest within the tapered or frustoconical section  26  of the bat barrel  12  defining the inner connection region  22 . The interconnecting member  16  may be formed of any suitable material, but typically is not comprised of metal. For example, the interconnecting member  16  can be comprised of a plastic or urethane material. 
     The interconnecting member  16  is attached to the bat barrel  12 , such as by gluing the interconnecting member  16  to the inner surface of the inner connection region  22 . More typically, however, the interconnecting member  16  has threads  28  on an outer surface thereof which are configured to engage and threadedly connect to inner threads  30  of the inner connection region  22 . Thus, the interconnecting member  16  is rotated with respect to the bat barrel  12  so as to threadedly connect the interconnecting member  16  to the inner connection region  22  of the bat barrel  12 . It will also be understood that an adhesive can be used in addition to the threaded connection in order to attach the interconnecting member  16  to the bat barrel  12 . 
     With reference again to  FIGS. 2 and 3 , typically the handle  14  is attached to the interconnecting member  16  before the interconnecting member  16  and bat barrel  12  are attached to one another. A first end of the handle  32  is attached to the interconnecting member  16 , and a second end of the handle  34  is used to pull the handle  14  and the interconnecting member  16  into the bat barrel  12 . The handle  14  will be passed through the hollow bat barrel  12  until the handle  14  substantially extends outwardly from the second open end  20  of the bat barrel, and the interconnecting member  16  is disposed at the inner connection region  24  of the bat barrel  12 . In fact, the handle  14  can be turned so as to rotate the interconnecting member  16  and threadedly attach it to the inner threads  30  of the inner connection region  22  of the bat barrel  12 . 
     The handle  14  can be attached to the interconnecting member  16  by any suitable means. In one embodiment, as illustrated, a first end  32  of the handle  14  is inserted into an opening  36  of the interconnecting member  16 . The opening  36  is generally cylindrical and has an inner diameter which is slightly larger than an outer diameter of the first end  32  of the handle  14  such that the first end  32  of the handle  14  fits snug therein. An adhesive may be applied to the first end  32  of the handle  14  and/or the inner surface of the opening  36  of the interconnecting member  16  so as to attach the handle  14  to the interconnecting member  16 . Alternatively, or in addition, apertures  38  may be formed through the handle  14 , such as at the first end  32  thereof, which are alignable with apertures  40  of the interconnecting member  16 , such that pins  42  can be inserted through the aligned apertures  38  and  40 , as illustrated in  FIGS. 4 and 5 . This further serves to securely attach and lock the handle  14  to the interconnecting member  16 . This is typically done before the handle  14  and interconnecting member  16  are passed into the bat barrel  12 . 
     The handle can be comprised of any suitable material, including metal, a composite material, wood, and combinations thereof. In a particularly preferred embodiment, however, the handle  14  is comprised of a composite material. This material is relatively lightweight, yet strong and durable. It also provides flexibility and does not transmit vibrations to the extent that a metal handle would. 
     In accordance with the present invention, a composite tube comprising the handle  14  is manufactured by first making a prepreg, using carbon fiber, fiberglass, Kevlar, and resin. The prepreg sheets are tailored as required to preset fiber angle and shape. The prepreg sheets are rolled over a mandrel by a rolling machine. Tape, such as BOPP (bioxially oriented polypropelene) tape is wrapped over the preform and mandrel by a wrapping machine. The preform is put into a curing oven. After curing, the composite tube is removed from the mandrel, and the tape is removed from the composite tube. The composite tube is then cut to the preset length necessary for the handle. Typically, the handle  14  is of a generally constant outer diameter. 
     In order to assemble the bat  10  of the present invention, glue is typically applied onto the composite tube comprising the handle  14 . This typically is at the first end  32  of the handle  14 . The first end  32  is inserted into the opening or passageway  36  of the interconnecting member  16 . In one embodiment, as illustrated, pins  42  are inserted through aligned apertures  38  and  40  of the handle  14  and interconnecting member  16  to further secure and attach and lock the handle  14  to the interconnecting member  16 . 
     Glue may be applied to an inner surface of the bat barrel  12 , such as at the inner connection region  22 . Alternatively, an adhesive is applied to the outer surface of the interconnecting member  16 . The handle  14 , having the interconnecting member  16  at the end thereof, is pulled through the bat barrel  12  until the second end  34  of the handle, and a significant portion or even all of the handle  14  is extending outwardly from the second open end  20  of the bat barrel  12 . The handle  14  and bat barrel  12  are turned relative to one another so as to threadedly connect the interconnecting member  16  and the inner connecting region  22 , such that the threads thereof  28  and  30  form a threaded connection. This effectively attaches and locks the handle  14  to the bat barrel  12 . 
     The bar barrel shell  12  may be sanded and cleaned, and graphics and paint applied thereto as desired. An end cap  44  is typically attached to the first open end  18  of the bat barrel. A grip  46  and a knob  48 , as necessary, are attached to the handle  14  to complete the bat  10 . 
     The end cap  44  typically has a groove  50  formed in an outer peripheral surface thereof into which a lip or projection  52  of the bat barrel  12  is inserted. An annular groove  54  may also be formed in the bat barrel  12 , adjacent to the first open end  18  which receives a mating circumferential projection  56  of the end cap  44 . This enables the end cap  44  to be threadedly attached to the first end of the bat barrel  12 , or forcibly inserted into the first end  18  of the bat barrel  12  so as to form a frictional fit therewith, with the various projections and grooves  50 - 56  forming a locking connection. The end cap  44  is typically comprised of a non-metallic material, such as a plastic material, a polymer material or the composite laminate. 
     It will be appreciated that the size, that is the length, of the end cap  44  can vary as needed. Thus, in some cases, the generally cylindrical hitting portion  24  of the bat barrel  12  may be relatively long and the end cap  44  relatively short. In other cases, the end cap  44  is longer and the hitting cylindrical barrel section  24  of the bat barrel  12  is shorter, depending on the desired characteristics of the bat. 
     With reference now to  FIGS. 7 and 8 , a separate knob  48  is attached to the second end  34  of the handle  14 . The knob  48  can be comprised of any suitable material, including aluminum or other metal, plastic, etc. The knob  48  includes a shaft  58  portion extending therefrom which is insertable into the open end of the handle  14 . Typically, the shaft portion  58  includes cutouts  60  to enable the shaft  58  to be compressible. Projections  62  typically extend outwardly from the shaft portion  58  so as to be snap fit into corresponding recesses  64  formed in the handle  14 . 
     Thus, in the embodiment illustrated in  FIGS. 7 and 8 , the shaft  58  of knob  48  is forcibly inserted into the second end  34  of the handle  14  until the projections  62  are snap fit into place within the recesses  64  of the handle  14 . Adhesive may be applied to the inner surface of the handle  14  and/or the outer surface of the shaft  58  so as to further attach the knob  48  to the handle  14 . The grip  46  is then applied over the outer surface of the handle  14 . 
     In another embodiment, a sheath  66  comprised of a relatively flexible material, such as rubber or polyurethane, forms both the grip and the knob  68 . This is a single member, wherein the knob  68  is an enlarged area at one end which extends over the end  34  of the handle  14 , and not in the handle  14 . The remainder of the sheath  66  forms the grip, which can be of varying designs. 
     It will be noted that the end  70  of the sheath  66  (or the grip  46 ) tapers outwardly and is somewhat enlarged with respect to the handle  14  and the remainder of the grip  46  or sheath  66 . With reference to  FIG. 5 , this is to allow the end of the grip  46  or sheath  66  to extend over an exposed end of the interconnecting member  16  extending outwardly of the second open end  20  of the bat barrel, so as to create a clean and aesthetically pleasing finish, as illustrated in  FIG. 1 . 
     The baseball or softball bat  10  of the present invention has many advantages over the prior art. It has the advantages of a multi-component bat, while being capable of meeting the standards of the various baseball and softball organizations. The bat is also relatively simple to manufacture and assemble. Moreover, it has been found that there is very little, if any, vibration at the handle under the impact between a bat and a ball. The “sweet spot” is much bigger than other bat designs. Furthermore, the swing weight is more balanced than other bat designs. It has also been found that the sound of a ball impacting the bat is louder and more uniform throughout the entire length of the bat barrel than with other composite and multi-component bat designs. 
     Although several embodiments have been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.