Patent Abstract:
Assembling a multi-component baseball bat includes disposing a rigid sleeve coaxially over a portion of an elongate composite handle. The rigid sleeve encircles a second end of the handle and extends toward a first end of the handle. A ring is positioned near a second end of a bat barrel. A first end of the bat barrel is inserted into the second end of the handle; the first end of the bat barrel being secured within the second end of the handle. An illustrative bat includes an elongate composite handle and an elongate barrel, each having opposite first and second ends. The first end of the barrel is disposed within the second end of handle. A mechanism secures the first end of the barrel within the second end of the handle. A rigid sleeve encircles the second end of the handle, extending towards the first end thereof.

Full Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to baseball and softball bats. More particularly, the present invention relates to a multi-component bat and a related assembly process. 
         [0002]    Baseball and softball are very popular sports in the United States, Mexico, Cuba, Japan and elsewhere. Due to the competitive nature of the 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. Aluminum (metal) 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. Such bats are advantageous over wood bats in that they do not break and splinter like wood bats and thus can be repeatedly used with consequent cost savings. Metal bats also have a larger optimal hitting area or power zone (commonly referred to as the “sweet spot”) than wood bats. Furthermore, the ball comes off a metal bat faster than a wood bat resulting in longer hits. 
         [0003]    However, metal bats have certain disadvantages. Metal bats vibrate upon impact and may send painful vibrations into the hands and arms of the batter if the ball is not hit within the power zone of the bat. Metal bats, particularly aluminum bats, may also dent or otherwise deform due to forceful impacts with the ball. Metal bats also emit an undesirable high-pitched metallic sound, as opposed to the traditional sound heard when a wood bat contacts the ball. 
         [0004]    Various attempts have been made to overcome the problems associated with metal bats. Some attempts have been to coat or wrap the exterior of the metal bat with materials such as carbon reinforcing fibers to enhance batting performance. These externally wrapped bats have been found to be aesthetically unpleasant and lacking in significant improvement. Other attempts have been made to insert internal layers or compartments within the metal bat to improve performance. Bats have been devised that incorporate both metal and composite materials. Such designs include utilizing multiple-layered graphite inserts to provide durability and flexibility to the bat, tubular coiled spring steel inserts to improve the spring-board effect when the ball contacts the bat, and pressurized air chambers within the bat. Bats that incorporate composite materials tend to be much lighter than metal bats. While providing benefits, these designs also have drawbacks. Some designs are very expensive to manufacture and are prone to structural failure. The composite sheaths break down over time, the bats are subject to premature longitudinal cracks in the barrel of the bat and damage is created at an interface of the metal and composite materials due to differences in the impact absorption and resistance characteristics of the materials. 
         [0005]    Accordingly, there is a need for a bat which enhances the performance of the bat and overcomes the disadvantages previously experienced with metal bats. The present invention fulfills these needs and provides other related advantages. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention resides in an apparatus and process that provides a multi-component bat. As illustrated herein, a multi-component baseball bat embodying the present invention includes an elongate composite handle having opposite first and second ends. The bat further includes an elongate barrel having opposite first and second ends, the first end of the barrel being disposed within the second end of handle. A mechanism is provided for securing the first end of the barrel within the second end of the handle. The bat also includes a ring disposed near the second end of the barrel, and a rigid sleeve encircling the second end of the handle and extending toward the first end of the handle. 
         [0007]    The sleeve is adhered to an exterior of the handle and barrel. The sleeve comprises, at least in part, an intermediate tapered section between the barrel and handle. 
         [0008]    The securing mechanism includes a section of the handle enveloping an end of the barrel. The securing mechanism also includes an annular recess in the handle for receiving the sleeve therein. 
         [0009]    A portion of the handle is disposed between the sleeve and barrel. The first end of the barrel and the second end of the handle threadedly engage each other. The bat includes a layer of adhesive disposed between the first end of the barrel and the second end of the handle. 
         [0010]    A cap is disposed on the second end of the barrel with the ring coaxially disposed within the cap such that the ring and sleeve contain vibrations within the barrel. 
         [0011]    The process for assembling a multi-component baseball bat includes disposing a rigid sleeve coaxially over a portion of an elongate composite handle, the rigid sleeve encircling a second end of the handle and extending toward a first end of the handle. A ring is positioned near the second end of the bat barrel. As part of the process, a first end of a bat barrel is inserted into the second end of the handle; the first end of the bat barrel being secured within the second end of the handle. 
         [0012]    A section of the barrel is enveloped within the second end of the handle. Disposing the rigid sleeve over the handle includes having formed the rigid sleeve and then molding the handle with the sleeve. The sleeve is received within an annular recess in the handle. 
         [0013]    Securing the barrel and handle together adhering the barrel to the handle. In addition, the barrel can be adhered to the sleeve. Securing the barrel and handle together can also be accomplished by threadedly engaging the first end of the barrel and the second end of the handle to define an intermediate tapered section. 
         [0014]    A continuous tapered exterior surface of the baseball bat is formed by engagement of the barrel, handle and sleeve. 
         [0015]    A grip can be attached to the handle and a cap disposed over an open second end of the bat barrel. 
         [0016]    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 
         [0017]    The accompanying drawings illustrate the invention. In such drawings: 
           [0018]      FIG. 1  is a perspective view of a baseball bat embodying the present invention; 
           [0019]      FIG. 2  is an exploded perspective view of a bat barrel, bat handle, and interconnecting mechanism of the baseball bat of  FIG. 1 ; 
           [0020]      FIG. 3  is an enlarged view of area  3  of an embodiment of the bat of  FIG. 2 ; 
           [0021]      FIG. 4  is cross-sectional view taken generally along the line  4 - 4  of  FIG. 1 ; 
           [0022]      FIG. 5  is an enlarged view of area  5  of another embodiment of the bat of  FIG. 2 ; 
           [0023]      FIG. 6  is cross-sectional view taken generally along the line  6 - 6  of  FIG. 1 ; 
           [0024]      FIG. 7  is an enlarged view of area  7  of yet another embodiment of the bat of  FIG. 2 ; 
           [0025]      FIG. 8  is cross-sectional view taken generally along the line  8 - 8  of  FIG. 1 ; 
           [0026]      FIG. 9  is an enlarged view of area  9  of the bat of  FIG. 2  illustrating attachment of an end plug to the bat barrel; 
           [0027]      FIG. 10  is an enlarged view of area  10  of the bat of  FIG. 1  illustrating the end plug on the bat barrel; 
           [0028]      FIG. 11  is a cross-sectional view taken generally along the line  11 - 11  of  FIG. 10 ; 
           [0029]      FIG. 12  is a perspective view of still another baseball bat embodying the present invention; 
           [0030]      FIG. 13  is an exploded perspective view of a bat barrel, bat handle, and interconnecting mechanism of the baseball bat of  FIG. 12 ; 
           [0031]      FIG. 14  is an enlarged view of area  14  of the bat of  FIG. 13 ; 
           [0032]      FIG. 15  is a top perspective view of a fluted ring used with the bat of  FIG. 12 ; 
           [0033]      FIG. 16  is cross-sectional view taken generally along the line  16 - 16  of  FIG. 12 ; 
           [0034]      FIG. 17  is an enlarged view of area  17  of the bat of  FIG. 13  illustrating attachment of an end plug to the bat barrel; 
           [0035]      FIG. 18  is an enlarged view of area  18  of the bat of  FIG. 12  illustrating the end plug on the bat barrel; and 
           [0036]      FIG. 19  is a cross-sectional view taken generally along the line  19 - 19  of  FIG. 12 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    As shown in  FIGS. 1-11  for purposes of illustration, the present invention is concerned with a multi-component bat  20 ,  70 ,  120  for use in baseball or softball. 
         [0038]    In one embodiment of the present invention, as seen in  FIGS. 1-4 , and  9 - 11 , the multi-component bat  20  has an elongate hollow handle shell portion  22 , an elongate hollow barrel shell portion  24  and an intermediate cylindrically tapered section  26  interconnecting the handle portion  22  and the barrel portion  24 . A knob  28  is securely attached to an end of the handle portion  22  by a variety of means including, without limitation, bonding agents, glues, adhesives or the like. The knob  28  may be made of various materials including, without limitation, aluminum, magnesium, polyurethane, polycarbonate, a composite material, Zytel, Delrin, plastic or the like. Also, the handle portion  22  is typically wrapped with a grip  30  comprised of rubber, polyurethane, leather or the like, for comfort. The construction of the intermediate tapered section  26  dampens vibrations created when a ball contacts the bat  20  and provides limited pivotal movement of the barrel portion  24  relative to the handle portion  22  (i.e., a flex measured in microns). 
         [0039]    The handle and barrel portions  22 ,  24  may be made of various materials including, without limitation, wood, a lightweight yet durable metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers (e.g., 50/50 glass to carbon, 80/20 glass to carbon for a very flexible bat, 20/80 glass to carbon for a very stiff bat or any other ratio of glass to fiber in order to obtain a desired flex in the bat  20 )) or the like. Each of the portions  22 ,  24  may be made of the same material or they may be made of different materials. Preferably, the handle portion  22  is comprised of a composite material and the barrel portion  24  is comprised of a 6000 or 7000 series aluminum alloy in which zinc is the major alloying element coupled with a smaller percentage of magnesium, resulting in a heat-treatable alloy of very high strength. The barrel portion  24  is finished to a mechanical strength of T6/T7 Temper. In the alternative, the handle and barrel portions  22 ,  24  may both be made of composite materials (of equal or differing hardness) or metal (of equal of differing hardness). In another alternative, the barrel portion  24  may be made of a composite material, such as those described above, and the handle portion  22  made of a metal, such as those described above. 
         [0040]    The handle and barrel portions  22 ,  24  each include a tapered first end  32 ,  34  having an aperture  36 ,  38 . The intermediate tapered section  26  of the bat  20  is defined, at least in part, when an interior surface of the tapered first end  32  of the handle portion  22  includes an adhesive layer  40  that engages an adhesive layer  42  on an exterior surface of the tapered first end  34  of the barrel portion  24 . A section of the handle portion  22  envelopes the end  34  of the barrel portion  24  with the adhesive layers  40 ,  42  disposed between the first end  34  of the barrel portion  24  and the first end  32  of the handle portion  22 . Preferably, the length of the adhesive section takes up approximately 10%-75% of the length of the tapered section  26 . The adhesive engagement of the handle and barrel portions  22 ,  24  coaxially interconnects the handle and barrel portions  22 ,  24 , in an aligned relation in order to provide impact absorption and reduce stress on an interface section  44  of the handle and barrel portions  22 ,  24  which forms a portion of the intermediate tapered section  26  of the bat  20 . 
         [0041]    The stress on the interface section  44  results from repeated impacts of a ball on the bat  20 . The intermediate tapered section  26  deflects vibrations traveling from the barrel portion  24  to the handle portion  22 ; deflecting the energy of the vibrations back into the barrel portion  24 . The deflected energy is transmitted, at least in part, back to the ball. 
         [0042]    The intermediate section  26  includes a rigid cylindrically tapered ring or sleeve  46  attached to the first end  32  of the handle portion  22 . The sleeve  46  comprises, at least in part, the intermediate tapered section  26  between the barrel and handle portions  24 ,  22 . The sleeve  46 , in the form of a hollow, exteriorly tapered sleeve, is coaxially disposed around an exterior of the first end  32  of the handle portion  22 . The sleeve  46  is coaxially disposed between the barrel portion  24  and the handle portion  22  for interconnecting the barrel and handle portions  24 ,  22  in an aligned relation, to return energy and power to the barrel portion  24  that emanates from the barrel portion  24  due to an impact of a ball (not shown) on the barrel portion  24 . 
         [0043]    The handle portion  22  includes a cylindrical guide  48  in the handle portion  22  for receiving the sleeve  46  thereabout. The guide  48  extends a distance longitudinally from the first end  32  of the handle portion  22  towards a second, opposite end  50  of the handle portion  22  where the knob  28  is located. The aperture  36  of the first end  32  of the handle portion  22  is the entrance to an interior portion  52  of the guide  48  that extends into the handle portion  22 . The sleeve  46  includes a central bore  54  having first and second tapered ends  56 ,  58 . The cylindrical interior diameter of the bore  54  of the sleeve  46  closely matches the cylindrical exterior diameter of the tapered guide  48  in order to provide tight engagement of the sleeve  46  and guide  48 . The sleeve  46  is also adhered about the guide  48  by a conventional adhesive, glue or bonding agent  60 . When the handle portion  22  engages the barrel portion  24 , the glue or bonding agent  60  also adheres the sleeve  46  to the exterior of the barrel portion  24 . The guide  48  and the tapered first end  34  of the barrel portion  24  each define, in part, an annular recess  62  of the intermediate section  26  of the bat  20 . The first and second tapered ends  56 ,  58  of the sleeve  46  engage tapered ends of the recess  62  such that a continuous exterior surface of the bat  20  is formed. When the handle portion  22  engages the barrel portion  24 , a portion of the end  32  of the handle portion  22  is disposed between the sleeve  46  and the barrel portion  24 . 
         [0044]    The engagement of the barrel portion  24 , the handle portion  22  and the sleeve  46  provides a generally continuous exterior surface of the baseball bat  20 . This is, at least partially, because the angle of the tapered exterior surface of the sleeve  46  matches the angles of the tapered first ends  32 ,  34  of the handle and barrel portions  22 ,  24 ; the angle of the first tapered ends  32 ,  34  being between zero and forty-five degrees. 
         [0045]    The sleeve  46  is comprised of polyurethane, or polycarbonate, a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers), metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), or an elastomeric material (e.g., solid rubber, high performance rubber foam, silicone or similar materials). The sleeve  46  can be made of transparent material (colored or non-colored) or an opaque material (colored or non-colored). The sleeve  46  may be solid or partially hollowed out to decrease its weight. 
         [0046]    The bat  20  may be assembled in a number of ways. In one particular way, the handle portion  22  is mated with the barrel portion  24  by adhering the sleeve  46  about the guide  48 . The first end  34  of the barrel portion  24  is inserted through the aperture  36  of the open first end  32  of the handle portion  22  with the adhesive layers  40 ,  42  bonding the barrel portion  24  to the handle portion  22  once the barrel portion  24  engages the sleeve  46  and can travel no further into the interior portion  52  of the handle portion  22 . The securement of the handle and barrel portions  22 ,  24 , with the sleeve  46  disposed therebetween in the recess  62  formed thereby, provides a generally continuous exterior surface of the baseball bat  20  when the handle portion  22  engages the barrel portion  24 . 
         [0047]    The components of the intermediate tapered section  26  tightly fit together to isolate vibrations which insulates the handle portion  22  from vibrations generated in the barrel portion  24  when a ball strikes the barrel portion  24 . The length of the intermediate tapered section  26  will be varied based on the size and type of bat (e.g., adult baseball bat, youth baseball bat, softball bat or the like). The high strength bonding agent  60  (e.g. rubberized glue, rubber cement, etc.) may be applied to all joins to secure all the connections. The bonding agent  60  helps to dampen vibrations, fill in gaps and allow additional flexibility. The flexibility of the bonding agent  60  helps to give the bat  20  a whipping effect since the two materials that form, respectively, the handle and barrel portions  22 ,  24  flex at different rates (the barrel portion  24  flexing more than the handle portion  22 ) and the bonding agent  60  provides a flexible cushion along the interface of the sleeve  46 , handle portion  22  and barrel portion  24 . 
         [0048]    A second end  64  of the barrel portion  24  is typically open and directed inward for acceptance and retention of a rigid cap or end plug  66  that increases the rigidity of the bat  20 . The end plug  66  is typically comprised of urethane, polyurethane, Zytel or the like. The end plug  66  has a circumferential outer groove  68  which accepts an inwardly directed annular lip  70  of the barrel portion  24 . The end plug  66  is then secured to the end  64  of the barrel portion  24  by inserting a number pairs of keys  72  disposed on opposite sides of the end plug  66  into slots or keyholes  74  disposed on opposite sides of the lip  72  and rotating the end plug  66  therein. Bonding agent  60  may be used to secure the end plug  66  in position. A recess  76  is formed on a top surface of the end plug  66  in order to allow a tool having a complimentary shape to the recess  76  engage the end plug  66  in order to secure the end plug  66  within the barrel  24 . The end plug  66  includes a circumferential inner groove  78  within which a rigid ring  80  is at least partially disposed. The sleeve  46  at the intermediate section  26  blocks vibrations by itself, and in combination with the ring  80  within the end plug  66 , the sleeve  46  and the ring  80  interact to create a larger sweet spot along the length of the barrel  24 . The sleeve  46  and the ring  80 , disposed at opposite ends  34 ,  64  of the barrel  24 , cooperate to contain vibrations that occur when a ball hits the bat  20  as well as channel those vibrations in order to increase the volume of a desirable “ping” sound that occurs from the ball hitting the bat  20 . The ring  80  is made of a  65 D polyurethane material that allows a softer durometer material to be used in the end plug  66 . 
         [0049]    In another embodiment of the present invention, as seen in  FIGS. 1 ,  2 ,  5 ,  6 , and  9 - 11 , a multi-component bat  120 , similar to the bat  20  described above, has an elongate hollow handle shell portion  122 , an elongate hollow barrel shell portion  124  and an intermediate cylindrically tapered section  126  interconnecting the handle portion  122  and the barrel portion  124 . A knob  128  is securely attached to the end of the handle portion  122  by a variety of means including, but not limited to, bonding agents, glues, adhesives or the like. The knob  128  may be made of various materials including, without limitation, aluminum, magnesium, Zytel, Delrin, plastic, polyurethane, polycarbonate, a composite material or the like. Also, the handle portion  122  is typically wrapped with a grip  130  comprised of rubber, polyurethane, leather or the like, for comfort. The construction of the intermediate tapered section  126  dampens vibrations created when a ball contacts the bat  120  and provides limited pivotal movement of the barrel portion  124  relative to the handle portion  122  (i.e., a flex measured in microns). 
         [0050]    The handle and barrel portions  122 ,  124  may be made of various materials including, without limitation, wood, a lightweight yet durable metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers (e.g., 50/50 glass to carbon, 80/20 glass to carbon for a very flexible bat, 20/80 glass to carbon for a very stiff bat or any other ratio of glass to fiber in order to obtain a desired flex in the bat  120 )) or the like. Each of the portions  122 ,  124  may be made of the same material or they may be made of different materials. Preferably, the handle portion  122  is comprised of a composite material and the barrel portion  124  is comprised of a 6000 or 7000 series aluminum alloy in which zinc is the major alloying element coupled with a smaller percentage of magnesium, resulting in a heat-treatable alloy of very high strength. The barrel portion  124  is finished to a mechanical strength of T6/T7 Temper. In the alternative, the handle and barrel portions  72 ,  74  may both be made of composite materials (of equal or differing hardness) or metal (of equal of differing hardness). In another alternative, the barrel portion  124  may be made of a composite material, such as those described above, and the handle portion  122  made of a metal, such as those described above. 
         [0051]    The handle and barrel portions  122 ,  124  each include a tapered first end  132 ,  134  having an aperture  136 ,  138 . The intermediate tapered section  126  of the bat  120  is defined, at least in part, when the first end  134  of the barrel portion  124  and the first end  132  of the handle portion  122  threadedly engage each other. An interior surface of the tapered first end  132  of the handle portion  122  includes threads  140  that engage threads  142  on an exterior surface of the tapered first end  134  of the barrel portion  124 . A section of the handle portion  122  envelopes the end  134  of the barrel portion  124  with the engaged threads  140 ,  142  disposed between the first end  134  of the barrel portion  124  and the first end  132  of the handle portion  122 . Preferably, the length of the threaded section takes up approximately 10%-75% of the length of the tapered section  126 . The threaded engagement of the handle and barrel portions  122 ,  124  coaxially interconnects the handle and barrel portions  122 ,  124 , in an aligned relation in order to provide impact absorption and reduce stress on an interface section  144  of the handle and barrel portions  122 ,  124  which forms a portion of the intermediate tapered section  126  of the bat  120 . The stress on the interface section  144  results from repeated impacts of a ball on the bat  120 . The intermediate tapered section  126  deflects vibrations traveling from the barrel portion  124  to the handle portion  122 ; deflecting the energy of the vibrations back into the barrel portion  124 . The deflected energy is transmitted, at least in part, back to the ball. 
         [0052]    The intermediate section  126  includes a rigid cylindrically tapered ring or sleeve  146  attached to the first end  132  of the handle portion  122 . The sleeve  146  comprises, at least in part, the intermediate tapered section  126  between the barrel and handle portions  124 ,  122 . The sleeve  146 , in the form of a hollow, exteriorly tapered sleeve, is coaxially disposed around an exterior of the first end  132  of the handle portion  122 . The sleeve  146  is coaxially disposed between the barrel portion  124  and the handle portion  122  for interconnecting the barrel and handle portions  124 ,  122  in an aligned relation, to return energy and power to the barrel portion  124  that emanates from the barrel portion  124  due to an impact of a ball (not shown) on the barrel portion  124 . 
         [0053]    The handle portion  122  includes a cylindrical guide  148  in the handle portion  122  for receiving the sleeve  146  thereabout. The guide  148  extends a distance longitudinally from the first end  132  of the handle portion  122  towards a second, opposite end  150  of the handle portion  122  where the knob  128  is located. The aperture  136  of the first end  132  of the handle portion  122  is the entrance to an interior portion  152  of the guide  148  that extends into the handle portion  122 . The sleeve  146  includes a central bore  154  having first and second tapered ends  156 ,  158 . The cylindrical interior diameter of the bore  154  of the sleeve  146  closely matches the cylindrical exterior diameter of the tapered guide  148  in order to provide tight engagement of the sleeve  146  and guide  148 . The sleeve  146  is also adhered about the guide  148  by a conventional adhesive, glue or bonding agent  160 . When the handle portion  122  engages the barrel portion  124 , the glue or bonding agent  160  also adheres the sleeve  146  to the exterior of the barrel portion  124 . The guide  148  and the tapered first end  134  of the barrel portion  124  each define, in part, an annular recess  162  of the intermediate section  126  of the bat  120 . The first and second tapered ends  156 ,  158  of the sleeve  146  engage tapered ends of the recess  162  such that a continuous exterior surface of the bat  120  is formed. When the handle portion  122  engages the barrel portion  124 , a portion of the end  132  of the handle portion  122  is disposed between the sleeve  146  and the barrel portion  124 . 
         [0054]    The engagement of the barrel portion  124 , the handle portion  122  and the sleeve  146  provides a generally continuous exterior surface of the baseball bat  120 . This is, at least partially, because the angle of the tapered exterior surface of the sleeve  146  matches the angles of the tapered first ends  132 ,  134  of the handle and barrel portions  122 ,  124 ; the angle of the first tapered ends  132 ,  134  being between zero and forty-five degrees. 
         [0055]    The sleeve  146  is comprised of polyurethane, or polycarbonate, a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers), metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), or an elastomeric material (e.g., solid rubber, high performance rubber foam, silicone or similar materials). The sleeve  146  can be made of transparent material (colored or non-colored) or an opaque material (colored or non-colored). The sleeve  146  may be solid or partially hollowed out to decrease its weight. 
         [0056]    The bat  120  may be assembled in a number of ways. In one particular way, the handle portion  122  is mated with the barrel portion  124  by adhering the sleeve  146  about the guide  148 . The first end  134  of the barrel portion  124  is inserted through the aperture  136  of the open first end  132  of the handle portion  122  with the threads  140 ,  142  engaging the barrel portion  124  to the handle portion  122  until the barrel portion  124  can travel no further into the interior portion  152  of the handle portion  122 . The securement of the handle and barrel portions  122 ,  124 , with the sleeve  146  disposed therebetween in the recess  162  formed thereby, provides a generally continuous exterior surface of the baseball bat  120  when the handle portion  122  engages the barrel portion  124 . 
         [0057]    The components of the intermediate tapered section  126  tightly fit together to isolate vibrations which insulates the handle portion  122  from vibrations generated in the barrel portion  124  when a ball strikes the barrel portion  124 . The length of the intermediate tapered section  126  will be varied based on the size and type of bat (e.g., adult baseball bat, youth baseball bat, softball bat or the like). The high strength bonding agent  160  (e.g. rubberized glue, rubber cement, etc.) may be applied to all joins to secure all the connections. The bonding agent  160  helps to dampen vibrations, fill in gaps and allow additional flexibility. The flexibility of the bonding agent  160  helps to give the bat  120  a whipping effect since the two materials that form, respectively, the handle and barrel portions  122 ,  124  flex at different rates (the barrel portion  124  flexing more than the handle portion  122 ) and the bonding agent  160  provides a flexible cushion along the interface of the sleeve  146 , handle portion  122  and barrel portion  124 . 
         [0058]    A second end  164  of the barrel portion  124  is typically open and directed inward for acceptance and retention of a rigid cap or end plug  166  that increases the rigidity of the bat  120 . The end plug  166  is typically comprised of urethane, polyurethane, Zytel or the like. The end plug  166  has a circumferential outer groove  168  which accepts an inwardly directed annular lip  170  of the barrel portion  124 . The end plug  166  is then secured to the end  164  of the barrel portion  124  by inserting a number pairs of keys  172  disposed on opposite sides of the end plug  166  into slots or keyholes  174  disposed on opposite sides of the lip  172  and rotating the end plug  166  therein. Bonding agent  160  may be used to secure the end plug  166  in position. A recess  176  is formed on a top surface of the end plug  166  in order to allow a tool having a complimentary shape to the recess  176  engage the end plug  166  in order to secure the end plug  166  within the barrel  124 . The end plug  166  includes a circumferential inner groove  178  within which a rigid ring  180  is at least partially disposed. The sleeve  146  at the intermediate section  126  blocks vibrations by itself, and in combination with the ring  180  within the end plug  166 , the sleeve  146  and the ring  180  interact to create a larger sweet spot along the length of the barrel  124 . The sleeve  126  and the ring  180 , disposed at opposite ends  134 ,  164  of the barrel  124 , cooperate to contain vibrations that occur when a ball hits the bat  120  as well as channel those vibrations in order to increase the volume of a desirable “ping” sound that occurs from the ball hitting the bat  120 . The ring  180  is made of a  65 D polyurethane material that allows a softer durometer material to be used in the end plug  166 . 
         [0059]    In another embodiment of the present invention, as seen in  FIGS. 1 ,  2  and  7 - 11 , the multi-component bat  220 , similar to the bat  20 ,  120  described above, has an elongate hollow handle shell portion  222 , an elongate hollow barrel shell portion  224  and an intermediate cylindrically tapered section  226  interconnecting the handle portion  222  and the barrel portion  224 . A knob  228  is securely attached to the end of the handle portion  222  by a variety of means including, but not limited to, bonding agents, glues, adhesives or the like. The knob  228  may be made of various materials including, without limitation, aluminum, magnesium, Zytel, Delrin, plastic, polyurethane, polycarbonate, a composite material or the like. Also, the handle portion  222  is typically wrapped with a grip  230  comprised of rubber, polyurethane, leather or the like, for comfort. The construction of the intermediate tapered section  226  dampens vibrations created when a ball contacts the bat  220  and provides limited pivotal movement of the barrel portion  224  relative to the handle portion  222  (i.e., a flex measured in microns). 
         [0060]    The handle and barrel portions  222 ,  224  may be made of various materials including, without limitation, wood, a lightweight yet durable metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers (e.g., 50/50 glass to carbon, 80/20 glass to carbon for a very flexible bat, 20/80 glass to carbon for a very stiff bat or any other ratio of glass to fiber in order to obtain a desired flex in the bat  220 )) or the like. Each of the portions  222 ,  224  may be made of the same material or they may be made of different materials. Preferably, the handle portion  222  is comprised of a composite material and the barrel portion  224  is comprised of a 6000 or 7000 series aluminum alloy in which zinc is the major alloying element coupled with a smaller percentage of magnesium, resulting in a heat-treatable alloy of very high strength. The barrel portion  224  is finished to a mechanical strength of T6/T7 Temper. In the alternative, the handle and barrel portions  222 ,  224  may both be made of composite materials (of equal or differing hardness) or metal (of equal of differing hardness). In another alternative, the barrel portion  224  may be made of a composite material, such as those described above, and the handle portion  222  made of a metal, such as those described above. 
         [0061]    The handle and barrel portions  222 ,  224  each include a tapered first end  232 ,  234  having an aperture  236 ,  238 . The intermediate tapered section  226  of the bat  220  is defined, at least in part, when the first end  234  of the barrel portion  224  and the first end  232  of the handle portion  212  engage each other. An interior surface of the tapered first end  232  of the handle portion  222  includes corrugations  240  that engage corrugations  242  on an exterior surface of the tapered first end  234  of the barrel portion  224 . The corrugations  240 ,  242  absorb and block vibrations from traveling from the barrel to the handle. A section of the handle portion  222  envelopes the end  234  of the barrel portion  224  with the engaged corrugations  240 ,  242  disposed between the first end  234  of the barrel portion  224  and the first end  232  of the handle portion  222 . Preferably, the length of the threaded section takes up approximately 10%-75% of the length of the tapered section  226 . The engagement of the respective corrugations  140 ,  142  of the handle and barrel portions  222 ,  224  coaxially interconnects the handle and barrel portions  222 ,  224 , in an aligned relation in order to provide impact absorption and reduce stress on an interface section  244  of the handle and barrel portions  222 ,  224  which forms a portion of the intermediate tapered section  226  of the bat  220 . The stress on the interface section  244  results from repeated impacts of a ball on the bat  220 . The intermediate tapered section  226  deflects vibrations traveling from the barrel portion  224  to the handle portion  222 ; deflecting the energy of the vibrations back into the barrel portion  224 . The deflected energy is transmitted, at least in part, back to the ball. 
         [0062]    The intermediate section  226  includes a rigid cylindrically tapered ring or sleeve  246  attached to the first end  232  of the handle portion  222 . The sleeve  246  comprises, at least in part, the intermediate tapered section  226  between the barrel and handle portions  224 ,  222 . The sleeve  246 , in the form of a hollow, exteriorly tapered sleeve, is coaxially disposed around an exterior of the first end  232  of the handle portion  222 . The sleeve  246  is coaxially disposed between the barrel portion  224  and the handle portion  222  for interconnecting the barrel and handle portions  224 ,  222  in an aligned relation, to return energy and power to the barrel portion  224  that emanates from the barrel portion  224  due to an impact of a ball (not shown) on the barrel portion  224 . 
         [0063]    The handle portion  222  includes a cylindrical guide  248  in the handle portion  222  for receiving the sleeve  246  thereabout. The guide  248  extends a distance longitudinally from the first end  232  of the handle portion  222  towards a second, opposite end  250  of the handle portion  222  where the knob  228  is located. The aperture  236  of the first end  232  of the handle portion  222  is the entrance to an interior portion  252  of the guide  238  that extends into the handle portion  222 . The sleeve  246  includes a central bore  254  having first and second tapered ends  256 ,  258 . The cylindrical interior diameter of the bore  254  of the sleeve  246  closely matches the cylindrical exterior diameter of the tapered guide  248  in order to provide tight engagement of the sleeve  246  and guide  248 . The sleeve  246  is also adhered about the guide  248  by a conventional adhesive, glue or bonding agent  260 . When the handle portion  222  engages the barrel portion  224 , the glue or bonding agent  260  also adheres the sleeve  246  to the exterior of the barrel portion  224 . The guide  248  and the tapered first end  234  of the barrel portion  224  each define, in part, an annular recess  262  of the intermediate section  226  of the bat  220 . The first and second tapered ends  256 ,  258  of the sleeve  246  engage tapered ends of the recess  262  such that a continuous exterior surface of the bat  220  is formed. When the handle portion  222  engages the barrel portion  224 , a portion of the end  232  of the handle portion  222  is disposed between the sleeve  246  and the barrel portion  224 . 
         [0064]    The engagement of the barrel portion  224 , the handle portion  222  and the sleeve  246  provides a generally continuous exterior surface of the baseball bat  220 . This is, at least partially, because the angle of the tapered exterior surface of the sleeve  246  matches the angles of the tapered first ends  232 ,  234  of the handle and barrel portions  222 ,  224 ; the angle of the first tapered ends  232 ,  234  being between zero and forty-five degrees. 
         [0065]    The sleeve  246  is comprised of polyurethane, or polycarbonate, a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers), metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), or an elastomeric material (e.g., solid rubber, high performance rubber foam, silicone or similar materials). The sleeve  246  can be made of transparent material (colored or non-colored) or an opaque material (colored or non-colored). The sleeve  246  may be solid or partially hollowed out to decrease its weight. 
         [0066]    The bat  220  may be assembled in a number of ways. In one particular way, the handle portion  222  is mated with the barrel portion  224  by adhering the sleeve  246  about the guide  248 . The first end  234  of the barrel portion  224  is inserted through the aperture  236  of the open first end  232  of the handle portion  222  with the corrugations  240 ,  242  engaging the barrel portion  224  to the handle portion  222  until the barrel portion  224  can travel no further into the interior portion  252  of the handle portion  222 . The securement of the handle and barrel portions  222 ,  224 , with the sleeve  246  disposed therebetween in the recess  262  formed thereby, provides a generally continuous exterior surface of the baseball bat  220  when the handle portion  222  engages the barrel portion  224 . 
         [0067]    The components of the intermediate tapered section  226  tightly fit together to isolate vibrations which insulates the handle portion  222  from vibrations generated in the barrel portion  224  when a ball strikes the barrel portion  224 . The length of the intermediate tapered section  226  will be varied based on the size and type of bat (e.g., adult baseball bat, youth baseball bat, softball bat or the like). The high strength bonding agent  260  (e.g. rubberized glue, rubber cement, etc.) may be applied to all joins to secure all the connections. The bonding agent  260  helps to dampen vibrations, fill in gaps and allow additional flexibility. The flexibility of the bonding agent  260  helps to give the bat  220  a whipping effect since the two materials that form, respectively, the handle and barrel portions  222 ,  224  flex at different rates (the barrel portion  224  flexing more than the handle portion  222 ) and the bonding agent  260  provides a flexible cushion along the interface of the sleeve  246 , handle portion  222  and barrel portion  224 . 
         [0068]    A second end  264  of the barrel portion  224  is typically open and directed inward for acceptance and retention of a rigid cap or end plug  266  that increases the rigidity of the bat  220 . The end plug  266  is typically comprised of urethane, polyurethane, Zytel or the like. The end plug  266  has a circumferential outer groove  268  which accepts an inwardly directed annular lip  270  of the barrel portion  224 . The end plug  266  is then secured to the end  264  of the barrel portion  224  by inserting a number pairs of keys  272  disposed on opposite sides of the end plug  266  into slots or keyholes  274  disposed on opposite sides of the lip  272  and rotating the end plug  266  therein. Bonding agent  260  may be used to secure the end plug  266  in position. A recess  276  is formed on a top surface of the end plug  266  in order to allow a tool having a complimentary shape to the recess  276  engage the end plug  266  in order to secure the end plug  266  within the barrel  224 . The end plug  266  includes a circumferential inner groove  278  within which a rigid ring  280  is at least partially disposed. The sleeve  246  at the intermediate section  226  blocks vibrations by itself, and in combination with the ring  280  within the end plug  266 , the sleeve  246  and the ring  280  interact to create a larger sweet spot along the length of the barrel  224 . The sleeve  226  and the ring  280 , disposed at opposite ends  234 ,  264  of the barrel  224 , cooperate to contain vibrations that occur when a ball hits the bat  220  as well as channel those vibrations in order to increase the volume of a desirable “ping” sound that occurs from the ball hitting the bat  220 . The ring  280  is made of a  65 D polyurethane material that allows a softer durometer material to be used in the end plug  266 . 
         [0069]    In still another embodiment of the present invention, as seen in  FIGS. 12-19 , a multi-component bat  320 , similar to the bat  20 ,  120 ,  220  described above, has an elongate hollow handle shell portion  322 , an elongate hollow barrel shell portion  324  and an intermediate cylindrically tapered section  326  interconnecting the handle portion  322  and the barrel portion  324 . A knob  328  is securely attached to an end of the handle portion  322  by a variety of means including, without limitation, bonding agents, glues, adhesives or the like. The knob  328  may be made of various materials including, without limitation, aluminum, magnesium, polyurethane, polycarbonate, a composite material, Zytel, Delrin, plastic or the like. Also, the handle portion  322  is typically wrapped with a grip  330  comprised of rubber, polyurethane, leather or the like, for comfort. The construction of the intermediate tapered section  326  dampens vibrations created when a ball contacts the bat  320  and provides limited pivotal movement of the barrel portion  324  relative to the handle portion  322  (i.e., a flex measured in microns). 
         [0070]    The handle and barrel portions  322 ,  324  may be made of various materials including, without limitation, wood, a lightweight yet durable metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers (e.g., 50/50 glass to carbon, 80/20 glass to carbon for a very flexible bat, 20/80 glass to carbon for a very stiff bat or any other ratio of glass to fiber in order to obtain a desired flex in the bat  320 )) or the like. Each of the portions  322 ,  324  may be made of the same material or they may be made of different materials. Preferably, the handle portion  322  is comprised of a composite material and the barrel portion  324  is comprised of a 6000 or 7000 series aluminum alloy in which zinc is the major alloying element coupled with a smaller percentage of magnesium, resulting in a heat-treatable alloy of very high strength. The barrel portion  324  is finished to a mechanical strength of T6/T7 Temper. In the alternative, the handle and barrel portions  322 ,  324  may both be made of composite materials (of equal or differing hardness) or metal (of equal of differing hardness). In another alternative, the barrel portion  324  may be made of a composite material, such as those described above, and the handle portion  322  made of a metal, such as those described above. 
         [0071]    The handle and barrel portions  322 ,  324  each include a tapered first end  332 ,  334  having an aperture  336 ,  338 . The intermediate tapered section  326  of the bat  320  is defined, at least in part, when an interior surface of the tapered first end  332  of the handle portion  322  includes an adhesive layer  340  that engages an adhesive layer  342  on an exterior surface of the tapered first end  334  of the barrel portion  324 . A section of the handle portion  322  envelopes the end  334  of the barrel portion  324  with the adhesive layers  340 ,  342  disposed between the first end  334  of the barrel portion  324  and the first end  332  of the handle portion  322 . Preferably, the length of the adhesive section takes up approximately 10%-75% of the length of the tapered section  326 . The adhesive engagement of the handle and barrel portions  322 ,  324  coaxially interconnects the handle and barrel portions  322 ,  324 , in an aligned relation in order to provide impact absorption and reduce stress on an interface section  344  of the handle and barrel portions  322 ,  324  which forms a portion of the intermediate tapered section  326  of the bat  320 . 
         [0072]    The stress on the interface section  344  results from repeated impacts of a ball on the bat  320 . The intermediate tapered section  326  deflects vibrations traveling from the barrel portion  324  to the handle portion  322 ; deflecting the energy of the vibrations back into the barrel portion  324 . The deflected energy is transmitted, at least in part, back to the ball. 
         [0073]    The intermediate section  326  includes a rigid cylindrically tapered ring or sleeve  346  attached to the first end  332  of the handle portion  322 . The sleeve  346  comprises, at least in part, the intermediate tapered section  26  between the barrel and handle portions  324 ,  322 . The sleeve  346 , in the form of a hollow, exteriorly tapered sleeve having a fluted interior surface, is coaxially disposed around an exterior of the first end  332  of the handle portion  322 . A rubber or silicone ring  348 , disposed partially within the sleeve  346 , includes an exterior fluted surface that engages the interior fluted surface of the sleeve  346 . The sleeve  346  and ring  348  are coaxially disposed between the barrel portion  324  and the handle portion  322  for interconnecting the barrel and handle portions  324 ,  322  in an aligned relation, to return energy and power to the barrel portion  324  that emanates from the barrel portion  324  due to an impact of a ball (not shown) on the barrel portion  324 . 
         [0074]    The handle portion  322  includes a cylindrical guide  350  in the handle portion  322  for receiving the sleeve  346  and ring  348  thereabout. The guide  350  extends a distance longitudinally from the first end  332  of the handle portion  322  towards a second, opposite end  352  of the handle portion  322  where the knob  328  is located. The aperture  336  of the first end  332  of the handle portion  322  is the entrance to an interior portion  354  of the guide  350  that extends into the handle portion  322 . The sleeve  346  includes a central bore  356  having first and second tapered ends  358 ,  360 . The ring  348  is disposed near the second end  360 . The cylindrical interior diameter of the bore  356  of the sleeve  346  and the interior diameter of the ring  348  closely matches the cylindrical exterior diameter of the tapered guide  350  in order to provide tight engagement of the sleeve  346 , ring  348  and guide  350 . The sleeve  346  and ring  348  are also adhered about the guide  350  by a conventional adhesive, glue or bonding agent  362 . When the handle portion  322  engages the barrel portion  324 , the glue or bonding agent  362  also adheres the sleeve  346  and the ring  348  to the exterior of the barrel portion  324 . The guide  350  and the tapered first end  334  of the barrel portion  324  each define, in part, an annular recess  364  of the intermediate section  326  of the bat  320 . The first and second tapered ends  358 ,  360  of the sleeve  346  engage tapered ends of the recess  364  such that a continuous exterior surface of the bat  320  is formed. When the handle portion  322  engages the barrel portion  324 , a portion of the end  332  of the handle portion  322  is disposed between the sleeve  346 , the ring  348  and the barrel portion  324 . 
         [0075]    The engagement of the barrel portion  324 , the handle portion  322  and the sleeve  346  provides a generally continuous exterior surface of the baseball bat  320 . This is, at least partially, because the angle of the tapered exterior surface of the sleeve  346  matches the angles of the tapered first ends  332 ,  334  of the handle and barrel portions  322 ,  324 ; the angle of the first tapered ends  332 ,  334  being between zero and forty-five degrees. 
         [0076]    The sleeve  346  is comprised of polyurethane, or polycarbonate, a composite material (e.g., fiberglass, carbon fibers, or a combination of glass and carbon fibers), metal (e.g., aluminum, titanium, magnesium, or an alloy thereof), or an elastomeric material (e.g., solid rubber, high performance rubber foam, silicone or similar materials). The sleeve  346  can be made of transparent material (colored or non-colored) or an opaque material (colored or non-colored). The sleeve  346  may be solid or partially hollowed out to decrease its weight. 
         [0077]    The bat  320  may be assembled in a number of ways. In one particular way, the handle portion  322  is mated with the barrel portion  324  by adhering the sleeve  346  and the ring  348  about the guide  350 . The ring  348  may also be adhered to the sleeve  346 . The first end  334  of the barrel portion  324  is inserted through the aperture  336  of the open first end  332  of the handle portion  322  with the adhesive layers  340 ,  342  bonding the barrel portion  324  to the handle portion  322  once the barrel portion  324  engages the sleeve  346  and ring  350  and can travel no further into the interior portion  354  of the handle portion  322 . The securement of the handle and barrel portions  322 ,  324 , with the sleeve  346  and ring  348  disposed therebetween in the recess  364  formed thereby, provides a generally continuous exterior surface of the baseball bat  320  when the handle portion  322  engages the barrel portion  324 . 
         [0078]    The components of the intermediate tapered section  326  tightly fit together to isolate vibrations which insulates the handle portion  322  from vibrations generated in the barrel portion  324  when a ball strikes the barrel portion  324 . The length of the intermediate tapered section  326  will be varied based on the size and type of bat (e.g., adult baseball bat, youth baseball bat, softball bat or the like). The high strength bonding agent  362  (e.g. rubberized glue, rubber cement, etc.) may be applied to all joins to secure all the connections. The bonding agent  362  helps to dampen vibrations, fill in gaps and allow additional flexibility. The flexibility of the bonding agent  362  helps to give the bat  320  a whipping effect since the two materials that form, respectively, the handle and barrel portions  322 ,  324  flex at different rates (the barrel portion  324  flexing more than the handle portion  322 ) and the bonding agent  362  provides a flexible cushion along the interface of the sleeve  346 , the ring  348 , the handle portion  322  and the barrel portion  324 . 
         [0079]    A second end  366  of the barrel portion  324  is typically open and directed inward for acceptance and retention of a rigid cap or end plug  368  that increases the rigidity of the bat  320 . The end plug  368  is typically comprised of urethane, polyurethane, Zytel or the like. The end plug  368  has a circumferential outer groove  370  which accepts an inwardly directed annular lip  372  of the barrel portion  324 . The end plug  368  is then secured to the end  366  of the barrel portion  324  by inserting a number pairs of keys  374  disposed on opposite sides of the end plug  368  into slots or keyholes  376  disposed on opposite sides of the lip  372  and rotating the end plug  368  therein. Bonding agent  362  may be used to secure the end plug  368  in position. A recess  378  is formed on a top surface of the end plug  368  in order to allow a tool having a complimentary shape to the recess  378  engage the end plug  368  in order to secure the end plug  368  within the barrel  324 . The end plug  368  includes a circumferential inner groove  380  within which a rigid ring  382  is at least partially disposed. The sleeve  346  at the intermediate section  326  blocks vibrations by itself, and in combination with the ring  382  within the end plug  368 , the sleeve  346  and the ring  382  interact to create a larger sweet spot along the length of the barrel  324 . The sleeve  346  and the ring  382 , disposed at opposite ends  334 ,  366  of the barrel  324 , cooperate to contain vibrations that occur when a ball hits the bat  320  as well as channel those vibrations in order to increase the volume of a desirable “ping” sound that occurs from the ball hitting the bat  320 . The ring  382  is made of a  65 D polyurethane material that allows a softer durometer material to be used in the end plug  368 . 
         [0080]    An example of several methods of manufacturing the bat  20 ,  120 ,  220 ,  320  of the present invention will now be described. It is to be understood that the methods used may be altered in some respects while still creating a bat  20 ,  120 ,  220 ,  320  having the desired characteristics. Also, certain dimensions, materials, temperatures, etc. may be altered depending upon the size, weight and intended use of the resulting bat  20 ,  120 ,  220 ,  320 . The connection between the handle  22 ,  122 ,  222 ,  322  and barrel portions  24 ,  124 ,  224 ,  324  allows the balance between the handle  22 ,  122 ,  222 ,  322  and barrel portions  24 ,  124 ,  224 ,  324  to be adjusted so that the majority of the weight of the bat  20 ,  120 ,  220 ,  320  is at the intermediate section  26 ,  126 ,  226 ,  326 . The position of the intermediate section  26 ,  126 ,  226 ,  326  along the length of the bat  20 ,  120 ,  220 ,  320  may be adjusted as well as the length and/or thickness of the intermediate section  26 ,  126 ,  226 ,  326 . In general, the barrel portion  24 ,  124 ,  224 ,  324  has a minimum thickness of 0.070 inches and a maximum thickness of 0.115 inches. The thickness of the connection area of the bat  20 ,  120 ,  220 ,  320  is determined by the weight/size of the bat  20 ,  120 ,  220 ,  320 . 
         [0081]    The composite material handle portions  22 ,  122 ,  222 ,  322  may be manufactured using a variety of techniques. These techniques include, but are not limited to: resin transfer molding (RTM); vacuum resin transfer molding (VRTM); filament winding and wrapping technique. Using RTM, various layers of the composite material are pre-manufactured to from the handle portion  22 ,  122 ,  222 ,  322 . Wrapping technique provides a layer-by-layer formation of the handle portion  22 ,  122 ,  222 ,  322  that allows the manufacturer to control the flexibility of the handle portion  22 ,  122 ,  222 ,  322 . In general, the handle portion  22 ,  122 ,  222 ,  322  is formed by approximately sixteen to twenty layers of composite material, depending on fiber type, fiber thickness (0.001-0.003 inches), fiber area weight (FAW) and flex. 
         [0082]    A metal tube, such as an aluminum alloy tube, is provided at predetermined lengths and weights prior to manufacturing. For purposes of the following example, an aluminum alloy tube is provided for the manufacture of the barrel portion  24 ,  124 ,  224 ,  324  for the bat  20 ,  120 ,  220 ,  320 . 
         [0083]    The metal tube is first thermally treated. This is often referred to in the art as an annealing process. The thermal treatment softens the metal by removing the stress resulting from cold working. This process is to be repeated after a certain amount of cold work has been performed on the metal tubes. Before each cold forming process, the temperature of an anneal oven is set at four hundred ten degrees Centigrade. The aluminum tube is heated in the oven at this temperature for approximately three hours. The oven temperature is then decreased by twenty degrees Centigrade per hour, after the three hour soak time, until the temperature of the tubes has reached twenty degrees Centigrade. The aluminum tube is then heated at a temperature of two hundred thirty degrees Centigrade for two hours, at which point the oven temperature is reset to one hundred forty degrees Centigrade. The tube is removed from the oven when the temperature of the oven has reached one hundred forty degrees Centigrade. 
         [0084]    The tube is then cleaned. During the annealing process, an oxidation scale develops on the surface of the aluminum tube. An acid cleaning process is required to remove the oxidation scale. The tube is soaked in a sulfuric acid solution for approximately thirty minutes to remove the oxidation scale each time the tube is annealed. 
         [0085]    The tube is then formed into the barrel portion  24 ,  124 ,  224 ,  324  of desired thickness, contour and length. This wall forming process is a cold working process. It is performed to obtain a wall of a desired thickness. Several cold forming passes may have to be performed depending upon several factors including metal type and the type of bat  20 ,  120 ,  220 ,  320  desired. In the instant example, the tube forming the aluminum barrel portion  24 ,  124 ,  224 ,  324  is subject to the cold working process on the outside diameter and the wall thickness simultaneously to obtain a wall thickness ranging from the minimum thickness of 0.070 inches to the maximum thickness of 0.115 inches. The barrel portion  24 ,  124 ,  224 ,  324  is then cleaned. A degreasing process is required to remove all lubricants and residue substances out of the aluminum barrel portion  24 ,  124 ,  224 ,  324 . This is performed using an ultrasonic method with a detergent agent before and after the aluminum tube is annealed. 
         [0086]    The barrel portion  24 ,  124 ,  224 ,  324  is then cut, trimmed and swaged to a desired length and contour. A thin end of the aluminum barrel portion  24 ,  124 ,  224 ,  324  is trimmed to a predetermined length. It is important to have the thin ends of the aluminum barrel portions  24 ,  124 ,  224 ,  324  squarely trimmed to avoid folding problems when the tubes are swaged by a rotary taper swager. The aluminum barrel portion  24 ,  124 ,  224 ,  324  is swaged with a rotary swaging machine to obtain the desired contour shape and wall thickness. In the instant example, the required wall thickness after swaging is generally a minimum thickness of 0.070 inches and a maximum thickness of 0.115 inches for the barrel portion  24 ,  124 ,  224 ,  324 . 
         [0087]    The tapered sleeve  46 ,  146 ,  246 ,  346  may be formed using conventional methods which may vary. The tapered sleeve  46 ,  146 ,  246 ,  346  is shaped to obtain a desired contoured shape that will later assist in giving the exterior surface of the bat  20 ,  120 ,  220 ,  320  a generally continuous appearance. After forming the rigid sleeve  46 ,  146 ,  246 ,  346 , the handle portion  22 ,  122 ,  222 ,  322  can be molded with the sleeve  46 ,  146 ,  246 ,  346 . 
         [0088]    If necessary, after shaping, the barrel portion  24 ,  124 ,  224 ,  324  is cut to the desired length. 
         [0089]    The barrel portion  24 ,  124 ,  224 ,  324  is then thermally treated, quenched and aged in order to obtain a T6/T7 Temper. It is commonly known in the art to expose metal or alloys to a heating and cooling treatment to obtain desired conditions, properties and an increase in strength. The barrel portion  24 ,  124 ,  224 ,  324  is heat treated to obtain the highest tensile and yield strengths. The required temperature and time for the solution heat treatment is twenty-seven minutes at a temperature of four hundred eighty degrees Centigrade. After the barrel portion  24 ,  124 ,  224 ,  324  is heat treated, they are quenched immediately with either air or water. Quenching is a controlled rapid cooling of a metal from an elevated temperature by contact with a liquid, gas or solid. Precipitation from solid solution results in a change in properties of the alloy, usually occurring rapidly at elevated temperatures. The barrel portion  24 ,  124 ,  224 ,  324  is aged in an oven for twelve hours at one hundred thirty five degrees Centigrade. 
         [0090]    After aging, the tapered ends  34 ,  134 ,  234 ,  334  of the barrel portion  24 ,  124 ,  224 ,  324  are contoured by machining. The respective threads  142  and corrugations  242  of the barrel portions  124 ,  224  are machined to obtain the desired configuration and dimensions to closely receive the respective threads  140 , corrugations  242  and other parts of the handle portions  122 ,  222 . The end  34 ,  134 ,  234 ,  324  of the barrel portion  24 ,  124 ,  224 ,  324  is machined to achieve squareness and an angled exterior surface in order to obtain a snug mating with the handle portion  22 ,  122 ,  222 ,  322 . 
         [0091]    The barrel portion  24 ,  124 ,  224 ,  324  is then cleaned again. Due to the treatments, the barrel portions  24 ,  124 ,  224 ,  324  oxidizes. This oxidation is removed by an anodizing process. The barrel portion  24 ,  124 ,  224 ,  324  is anodized for five minutes. To eliminate all possible contaminations, the surface of the barrel portion  24 ,  124 ,  224 ,  324  is then thoroughly cleaned with methyl ethyl ketone. 
         [0092]    At this point, the barrel portion  24 ,  124 ,  224 ,  324  is assembled as outlined above, with respect to  FIGS. 1-19 . 
         [0093]    Thereafter, approximately a one half inch portion of the open barreled end  64 ,  164 ,  264 ,  366  is rolled inward at a ninety degree angle to accommodate the end plug  66 ,  166 ,  266 ,  368 . If necessary, the protruded portion of the rolled portion is machined to achieve an opening of one and a quarter inches in diameter for installing the end plug  66 ,  166 ,  266 ,  368 . The keyholes/slots  74 ,  174 ,  274 ,  376  are then machined into the lip  70 ,  170 ,  270 ,  372  and interior of the barrel portion  24 ,  124 ,  224 ,  324 . 
         [0094]    The bat  20 ,  120 ,  220 ,  320  is then polished and decorated. Any appropriate methods of polishing and decoration, as are well known in the art, can be applied. In the preferred embodiment, the outer surfaces of the barrel portion  24 ,  124 ,  224 ,  324  are exposed to sodium hydroxide to strip an anodize coating created during the manufacturing process as well as to prepare the outer surface for anodic coating process. Typically, the concentration of the sodium hydroxide is fifty grams per liter. The outer surface of the barrel portion  24 ,  124 ,  224 ,  324  is mechanically polished to obtain a mirror finish. The external surface of the barrel portion  24 ,  124 ,  224 ,  324  is then anodized. In the alternative, the external surface of the barrel portion  24 ,  124 ,  224 ,  324  may be painted, chromed, powder-coated, or covered by some other method of decorative coating. The outer surface of the barrel portion  24 ,  124 ,  224 ,  324  may be decorated with a graphic by using various methods such as silkscreening, heat transferring, or pad stamping. The handle portion  22 ,  122 ,  222 ,  322  may also be decorated using same/similar techniques. 
         [0095]    The bat  20 ,  120 ,  220 ,  320  is completed by attaching the knob  28 ,  128 ,  228 ,  328  typically by gluing the knob  28 ,  128 ,  228 ,  328  to an open end of the handle portion  22 ,  122 ,  222 ,  322  opposite the tapered end  32 ,  132 ,  232 ,  332 . The grip  30 ,  130 ,  230 ,  330  and the end plug  66 ,  166 ,  266 ,  368  are also installed to finish the bat  20 ,  120 ,  220 ,  320 . 
         [0096]    In the alternative, the above described method of manufacturing the bat  20 ,  120 ,  220 ,  320  may be varied. For example, physical characteristics of the bat  20 ,  120 ,  220 ,  320  such as the length, wall thickness or diameter may be increased or decreased. 
         [0097]    An important feature of the bat  20 ,  120 ,  220 ,  320  is the balance of the bat  20 ,  120 ,  220 ,  320 . The balance of the bat affects a user&#39;s control of the bat  20 ,  120 ,  220 ,  320 . The length L, thickness t and position P of the intermediate section  26 ,  126 ,  226 ,  326  of the bat  20 ,  120 ,  220 ,  320  affects the balance of the bat  20 ,  120 ,  220 ,  320 , as seen in  FIGS. 4 ,  6 ,  8  and  16 , respectively. 
         [0098]    Although constructed from affordable medium to high strength, light weight, and commercially available materials, the bat  20 ,  120 ,  220 ,  320  of the present invention offers the performance and advantages of expensive and high strength materials. The bat  20 ,  120 ,  220 ,  320  also dampens the vibrations created when traditional metal bats hit the ball that would otherwise sting the hitter&#39;s hand when a bat contacts a ball. Premature longitudinal cracking of the barrel portion  24 ,  124 ,  224 ,  324  caused in traditional bats with thin wall thicknesses and high stress conditions, is avoided in the present invention. 
         [0099]    The above-described embodiments of the present invention are illustrative only and not limiting. It will thus be apparent to those skilled in the art that various changes and modifications may be made without departing from this invention in its broader aspects. Therefore, the appended claims encompass all such changes and modifications as falling within the true spirit and scope of this invention.

Technology Classification (CPC): 0