Abstract:
An automatic leveling fixture includes a base, at least one jaw slidably connected to the base, a base plate slidable relative to the base. The at least one jaw has a base plate camming surface engaging the base plate and causing the at least one jaw to move a preselected distance relative to a distance moved by the base plate.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     None. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPLMENT 
     None. 
     REFERENCE TO SEQUENTIAL LISTINGS, ETC. 
     None 
     BACKGROUND 
     1. Field of the Invention 
     The present invention comprises a fixture for repeatedly positioning an object having an equilaterally shaped cross-section. More specifically, the present invention provides a fixture for baseball bats having an automatic leveling feature in order to position the bats at the same elevation for laser engraving baseball bats of differing diameter. 
     2. Description of the Related Art 
     One of the steps involved in manufacturing wooden baseball bats is to engrave the manufacturer&#39;s insignia, logos, or even personalize the barrel of the bats prior to finishing the manufacturing process. Engravings may be formed by heating a piece of metal defining the insignia and stamping or branding the insignia into the wooden barrel of the baseball bat. Alternatively, the insignia, logo, or personalization may be cut into the bat by a blade or other hardened metal cutting tool. In any event, these prior art methods are very labor intensive and alternative means of cutting the barrel of a bat were developed. 
     Currently one method of engraving which manufacturers are utilizing is through the use of lasers. The lasers are typically in a fixed positioned above the baseball bat and are aimed at the barrel while the bats are held in position by clamps or fixtures. As this technology has emerged, another problem has developed. As one skilled in the art is well aware, various types of baseball bats are formed having different weights and sizes and as a result have varying diameters. For example, children&#39;s bats are often small while college and professional bats are longer and heavier. Further, souvenir bats are also available which are smaller than children&#39;s bats. However, the lasers must always be positioned at the fixed distance from the upper surface of the baseball bat, regardless of the diameter, so that the laser stays properly focused for cutting. Since the baseball bats have varying diameters, the laser must continually be focused to a proper distance when bats of varying diameter are utilized. Manually focusing the laser for each personalized bat substantially slows the manufacturing time and reduces output for bat manufacturers. 
     However, heretofore none of the known clamps or bat fixtures compensate for the varying diameters typical with engraving a plurality of bat sizes. Therefore, manufacturers must continually stop engraving to adjust clamps or fixtures for differing bat sizes in order to re-focus the cutting lasers. 
     SUMMARY OF THE INVENTION 
     With regard to the foregoing, the present invention eliminates the oversights, difficulties, and disadvantages of the prior art by providing a bat fixture. 
     It is an object of the present invention to provide an automatic leveling bat fixture for laser engraving. 
     It is a further object of the present invention to provide an automatic leveling bat fixture which accepts baseball bats of differing diameters. 
     It is still a further object of the present invention to provide an automatic leveling bat fixture which repeatedly positions bats of differing diameter at the same elevation. 
     An automatic leveling bat fixture, comprising a base, at least one jaw slidably adjustable relative to the base, a base plate slidably adjustable relative to the base and the at least one jaw, the at least one jaw having a base plate camming surface engaging the base plate causing the at least one jaw to move a preselected distance relative to a distance moved by the base plate. The at least one jaw comprises a first jaw and a second jaw which each move one-half the distance moved by the base plate. The automatic leveling bat fixture further comprises a jaw channel extending through the base in a latitudinal direction wherein the at least one jaw slides relative to the base through the jaw channel. The jaw channel has a rail positioned therein. The at least one jaw may be two opposed jaws biased inwardly toward the base plate. The opposed jaws may be biased by a compression spring extending through the opposed jaws and the opposed jaws being mounted on a rail and slidable relative to the base. The at least one jaw includes a tapered receiving surface providing a lateral force component. The automatic bat leveling fixture further comprises camming rollers mounted within a notch of the base plate and slidably engaging a base plate camming surface. The automatic leveling bat fixture receives bats of differing diameter and positions the bats at equivalent elevations relative to a laser. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a automatic leveling bat fixture clamp of the present invention for retaining a baseball bat therein; 
         FIG. 2  is a perspective view of the automatic leveling bat fixture of  FIG. 1  shown without the bat; 
         FIG. 3  is an exploded perspective view of the automatic leveling bat fixture of  FIG. 2 ; 
         FIG. 4  is a side perspective view of a jaw of the fixture clamp of  FIG. 1 ; 
         FIG. 5  is a lower perspective view of a base plate and guide posts of the automatic leveling bat fixture of  FIG. 1 ; 
         FIG. 6  is a perspective view of a base of the automatic leveling bat fixture of  FIG. 1 ; 
         FIG. 7  is a side sectional view of the automatic leveling bat fixture of  FIG. 1  including a bat positioned therein; and, 
         FIG. 8  is a side sectional view of the automatic leveling bat fixture of  FIG. 7  including a second bat of a second diameter. 
     
    
    
     DETAILED DESCRIPTION 
     Given the foregoing deficiencies, it will be appreciated that a bat fixture is needed allowing placement repeated placement of bats of different diameter at the same elevation relative to an engraving laser or marking device. For purpose of this description, a baseball bat is shown and described as being held in place by the fixture of the present invention, however it should be understood that the fixture may be used to retain a plurality of objects having an equilateral cross-section. 
     Referring now in detail to the drawings, wherein like numerals indicate like elements throughout the several views, there is shown in  FIGS. 1-8  various aspects of an automatic leveling bat fixture  10 . The automatic leveling bat fixture  10  provides a clamping or retaining device which positions bats of differing diameters at the same elevation relative to a laser  11 . 
     Referring initially to  FIG. 1 , a perspective view of the automatic leveling bat fixture  10  and baseball bat  12  positioned within the automatic leveling bat fixture  10  for laser engraving of the bat barrel  13  is shown. In order to insure proper engraving, a laser  11  must be held at the same distance from the bat in a repeatable manner regardless of the diameter of the bat  12 . Thus, it is preferable to not move the laser  11  between bat changes but not absolutely necessary. The bat  12  must be repeatedly held at the same distance the automatic leveling bat fixture  10  comprises a base  14 , a base plate  16 , a first jaw  20 , and a second jaw  22 . The first jaw  20  and the second jaw  22  are biased inwardly toward the base plate  16  and spread away from one another as the bat  12  is interposed between the first and second jaws  20 ,  22  and against the base plate  16 . The illustrative embodiment of the present invention repeatedly positions a plurality of bats at the same elevation regardless of the bat diameter, to insure proper laser focus and engraving. 
     Referring now to  FIG. 2 , a perspective view of the automatic leveling bat fixture  10  is shown without the bat positioned between the first jaw  20  and second jaw  22  for purpose of clarity. As depicted, the first and second jaws  20 ,  22  are normally biased and positioned against the base plate  16  causing the base plate to be normally positioned some distance above an upper surface of a longitudinal jaw channel  40  extending across the base  14 . For purposes of this invention description, two directions will be defined by channels extending through the base  14 . 
     Referring now to  FIGS. 2 ,  3 , and  6  various aspects of the base  14  of the automatic leveling bat fixture  10  are shown and depict longitudinal and latitudinal channels extending there through. For purposes of the present description, a longitudinal direction will be defined by an upper base plate channel  30  extending across the upper portion of base  14  which is parallel to the major axis of base plate  16  and wherein the base plate  16  may be seated when the base plate  16  is fully positioned downward against the base  14 . Alternatively, a latitudinal direction is defined by a second channel extending through the base  14  and which is generally deeper than the longitudinal base plate channel and substantially orthogonal to the upper longitudinal channel extending through base  14 . The base  14  is may be substantially cubical in shape defined by four sides, and an upper and a lower surface. However the shape of the base need not be square and may be defined by a plurality of geometries not specifically shown herein. The base  14  may alternatively be described as two U-shaped bodies perpendicularly extruded and intersecting wherein one U-shaped body is deeper than the other U-shaped body. The base  14  further comprises an upper base plate channel  30  extending across the upper portion of the base in a longitudinal direction as previously defined from one side of the base  14  to an opposed side. The base plate channel  30  defines four plateaus  32  at four upper corner positions of the base  14  which act as sliding surfaces for the jaws  20 , 22  described further hereinafter. Within the lower surfaces of the base plate channel  30  are sleeve apertures  34  which are vertically oriented and extending downwardly through the base  14 . Within the sleeve apertures  34  are sleeves  36  which may be linear bearings or other friction reducing elements to provide for smooth vertical movement of the base plate  16  upwardly and downwardly through the sleeves  36  and which will also be described further hereinafter. 
     Extending through the base  14  in a substantially latitudinal direction perpendicular to the base plate channel  30  is a jaw channel  40  which is deeper than the base plate channel  30  and also defines the plateaus  32  formed by channel  30 . The jaw channel  40  extends from a first end of the base  14  to a second end of the base  14  and defines a position for a rail  42 . The rail  42  is fastened to the lower surface of jaw channel  40  by a plurality of fasteners  43  however it is well within the scope of the present invention that the rail  42  may be affixed with some fixative or other fastening or retaining device. Located at opposed ends of the rail  42  are stops  44  which are fastened to the rail  42 . The stops  44  inhibit removal of the first and second jaws  20 ,  22  once the jaws are slideably positioned on the rail  42 . 
     Referring now to  FIG. 3  and  FIG. 5 , which depicts the base plate  16  in a lower perspective view, the base plate  16  is shown being substantially parallelogram in shape, and more specifically having a substantially rectangular shape defined by an upper surface, a lower surface, and four side surfaces extending between the upper and lower surfaces. However, the base plate  16  may include a plurality of shapes preferably having opposed parallel sides for engagement with first and second jaws  20 , 22 . Depending from the lower surface of the base plate  16  are guideposts  18  which are substantially cylindrical or columnar in shape. Alternatively, the guideposts  18  may have different shapes as dictated by, and corresponding to, the sleeve apertures  34  and sleeves  36 . The lower ends of the guideposts  18  may have a slight taper or be rounded and are spaced apart a distance corresponding to the center distance between the sleeve apertures  34  in the base  14 . Thus, as one of ordinary skill in the art may understand, the tapered or rounded end of guideposts  18  facilitates feeding of the guideposts into the sleeves  16  and the linear bearings defining the sleeve  36  allow smooth movement of the guideposts  18  into and within the base  14 . Optionally, the guide posts  18  may include a catch, not shown, to inhibit removal of the base plate  16  from the base  14  once installed. 
     Along the outer edge of the longer sides of the base plate  16  and centrally positioned along the longer sides of the base plate  16  are camming rollers  46  which are positioned on roller axes  48 . A notch  47  is formed along a central portion of the longer sides of the base plate  16 . The notch  47  provides for positioning of the camming roller within the profile of the base plate  16 . The camming rollers  46  function to engage camming surfaces  60  on the first and second jaws  20 ,  22  in order to cause the base plate  16  to rise or fall corresponding to movement of the first and second jaws  20 ,  22  into and out of the jaw channel  40 . 
     Referring now to  FIG. 4 , the first jaw  20  is shown in perspective view and is illustrative of both the first jaw  20  and the second jaw  22 . The jaw  20  has a sled or jaw guide  50  located at a bottom portion of the jaw  20  which engages the rail  42  by receiving the cross-section of the rail  42 . More specifically, a rail channel  52  centrally positioned in the sled  50  and extending there through provides a connection allowing slidable positioning of the sled  50  and jaws  20 , 22  along the rail  42  and relative to the base  14 . In other words, the sled  50  allows movement in a latitudinal direction through the jaw channel  40 . The sled  50  or rail  42  may include linear bearings to inhibit binding and provide smooth motion of the sled  50  along the rail  42 . Positioned above the jaw guide or sled  50  is a platform  54  having a spring housing  56  extending horizontally through the platform  54  in a latitudinal direction as depicted in  FIGS. 2 ,  3 . As shown in  FIGS. 3 ,  7  and  8  a compression coil spring  58  provides a biasing force on the first and second jaws  20 ,  22  in order to pull the jaws  20 ,  22  inwardly in a latitudinal direction against the base plate  16 . The compression coil spring  58  is held in place by a retaining pins  59  at each end of the coil spring  58  and against outer surfaces of the platform  54  to bias the jaws  20 ,  22  latitudinally inwardly against the base plate  16 . 
     Extending upwardly from the platform  54  at a preselected angle is the base plate camming surface  60 . The camming surface  60  defines the hypotenuse of a right triangle wherein the horizontal leg  64  of the right triangle is one-half the length of the vertical leg  62  of the right triangle. In other words, the ratio of rise-to-run defined by the base plate camming surface  60  is 2-to-1 (2/1 ). 
     Referring briefly to  FIGS. 7 and 8 , the camming rollers  46  engage the base plate camming surfaces  60  of the first and second jaws  20 ,  22  so that as the base plate  16  moves downwardly, for instance when a bat is placed thereon, the jaws  20 ,  22  move a corresponding distance through the jaw channel  40  along rail  42 . Oppositely, when the jaws  20 , 22  move inwardly, the base plate  16  moves upwardly along the base plate camming surface  60 . More specifically, the angle of the camming surface  60  provides that each jaw  20 ,  22  moves inwardly or outwardly in a latitudinal direction one- half of the vertical distance moved by the base plate  16 . Otherwise stated, for each half unit that each jaw  20 , 22  moves, the base plate  16  moves a full unit. Stated in yet a another manner, the base plate  16  moves a distance equal to the total displacement of both jaws  20 , 22 . This geometry provides that bats of differing diameter may be positioned in the fixture  10  and always be positioned at the same height. 
     Extending from a rear portion of the base plate camming surface  60 , and more specifically the vertical leg of the triangle defining the base plate camming surface  60 , is a jaw plate  70 . The jaw plate  70  may be integrally formed with the jaw  20 , 22  or may be fastened or otherwise affixed thereto. The jaw plate  70  may be defined by a plurality of various shapes and is substantially rectangular in shape as shown in the present illustrative embodiment having a planar vertical surface normally disposed against the base plate  16 . At an upper portion of the jaw plate  70  is a tapered receiving surface  72  which guides the bat into the open area between the opposed first and second jaws  20 ,  22  and above base plate  16 . Further, the tapered receiving surface  72  creates a lateral force component on the jaws  20 ,  22  when a vertical force is placed on the jaws  20 ,  22  by the downward motion of a bat  12  being positioned in the automatic leveling bat fixture  10 . The lateral force component opposes the spring bias on jaws  20 , 22  causing the jaws  20 , 22  to spread apart in a latitudinal direction through jaw channel  40  in order to accommodate bats of different diameter and repeatedly position the bats at the same elevation. The jaw plate  70  engages a tangent point on the outer surface of the bat  12  when the bat is placed in the automatic leveling bat fixture  10  as shown in  FIG. 1 . 
     Referring now to  FIGS. 7 and 8 , side-sectional views of the automatic leveling bat fixture  10  are shown being utilized with two bats of different diameters in order to show that the automatic leveling bat fixture  10  repeatedly positions bats of different diameters at the same elevation relative to a laser  11  above the bat and automatic leveling bat fixture  10 . As shown in  FIG. 7 , a bat  12  having a first diameter is placed between the first and second jaws  20 ,  22  and has tangential contact with the opposed jaw plates  70 . The bat  12  also contacts the base plate  16  causing the first and second jaws  20 ,  22  to spread apart in a latitudinal direction and against the biasing force of the compression spring  58  as shown by the gap between the edges of the base plate  16  and the jaw plate  70 . In other words, the bat  12  is positioned within the automatic leveling bat fixture  10  so that the bat  12  has tangential contact with the base plate  16  and first and second jaws  20 ,  22 . When the first and second jaws  20 ,  22  and the base plate  16  are all in tangential contact with the bat  12 , the bat  12  is positioned at an elevation E 1  defined from the bottom of the base  14  to the top surface of the bat  12 . Referring now to  FIG. 8 , a second bat  112  is placed in the automatic leveling bat fixture  10  and has a second diameter greater than the diameter of the bat  12  previously shown and described in  FIG. 7 . As previously indicated, when the second bat  112  is in tangential contact with the first jaw  20 , the second jaw  22 , and the base plate  16 , the jaws  20 ,  22  are spread apart a distance greater than that shown in  FIG. 7  as indicated by the gap between the base plate  16  and the first and second jaws  20 ,  22  respectively. However, the elevation of the top surface of the bat is labeled E l  as depicted and shown in  FIG. 7 , and therefore is equal to the elevation E 1  shown in  FIG. 7  despite the fact that the second bat  112  has a diameter which is larger than the bat  12  of  FIG. 7 . 
     In operation, a bat  12  is positioned against the tapered receiving surface  72  and pushed downwardly against the inward bias on the jaws  20 , 22 . As discussed, the tapered surface  72  in combination with the downward force provides a lateral component force moving the jaws  20 , 22  outwardly against the spring bias. The bat  12  continues downwardly against the jaws  20 , 22  sliding along the jaw plate  70  until the bat  12  engages the base plate  16 . Over pushing of the bat  12  will result in the bat  12  losing contact with the jaw plates  70  as they move outwardly and the base plate  16  moves downward. Removal of the downward force results in the bias force compressing the jaws  20 , 22  against the bat  20  at which time the base plate  16  will rise as the plates  70  move inwardly in a latitudinal direction. When the fixture mechanically equalizes, the bat  12  will be in tangential contact with the base plate  16  and jaws  20 , 22 . At this time, the laser  11  may begin engraving. Once the bat is removed from the automatic leveling bat fixture  10 , the compression spring  58  biases the jaws  20 , 22  back together in a latitudinal direction through jaw channel  40  such that the jaw plate  70  is positioned against the base plate  16  and is therefore ready to accept a subsequent bat  12  for engraving.