Abstract:
Arrangements for clamping a large workpiece such as an I-beam to a precision assembly table (or fitup table) or other workpiece support. The clamping arrangement includes a base; a first track supported by the base; a first slider for sliding along the track; a second slider for sliding along the first track, wherein the first slider and the second slider are moveable relative to one another along the first track; a first spacer supported by the first slider; and a second spacer supported by the second slider; wherein the first spacer and the second spacer are adapted to grip the workpiece therebetween.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit under 35 U.S.C. §119(e) of the earlier filing date of U.S. Provisional Application Ser. No. 61/101,904 filed on Oct. 1, 2008, the entire disclosure of which is hereby incorporated by reference herein as if being set forth in its entirety. 
     
    
     FIELD OF INVENTION 
       [0002]    The invention relates to arrangements and processes for clamping a large workpiece. 
       BACKGROUND OF THE INVENTION 
       [0003]    Precision assembly tables (or fitup tables) historically have represented one highly useful arrangement for accommodating large workpieces such as magnetic levitation system guideways, wherein the workpieces are held securely for the purpose of undertaking precision work on the workpiece (such as welding). U.S. Pat. Nos. 6,453,544 and 6,202,275, both assigned to Maglev, Inc., provide examples and their disclosures are incorporated by reference herein. 
         [0004]    Consequently, by way of providing general background and also of appreciating a context in which embodiments of the invention may readily be employed,  FIG. 1  provides a perspective view of a conventional precision assembly table and basic components thereof. Additional details thereof may be appreciated from the prior Maglev patents cited hereinabove. It should be understood and appreciated that although a precision assembly table is shown in  FIG. 1  that primarily relates to magnetic levitation guideway assembly, general principles relating to fitup tables in general as well as components or aspects of the table of  FIG. 1  suitable for use with large workpieces in general can indeed be applicable to I-beams and other large workpieces as well as magnetic levitation guideways. It should also be readily understood and appreciated that fitup tables per se are provided as but one example of a possible mounting arrangement that could employ a clamping arrangement as broadly contemplated herein in accordance with at least one embodiment of the invention. 
         [0005]    As shown, a precision assembly table may include a frame  1  connected to a surface  2  over which rigid bars  3  are positioned by adjustable support members  4  which are connected to the rigid bars  3  and the frame  1  and necessarily pass through the surface  2 . As depicted, the frame  1  supports the surface  2  above the ground, and the frame further supports the adjustable support members  4  which protrude through the surface  2  to support the rigid bars  3  above the surface  2 , above the frame  1 , and above the ground. The frame  1  is very rigid and typically is connected to the factory floor or ground to prevent movement of the frame  1 , thereby avoiding interference with the assembly. The frame  1  can be of a variety of configurations, provided that it provides a rigid and stable apparatus upon which the surface  2  and adjustable support members  4  can be connected. The surface  2  is utilized to shield the frame  1  and the apparatus associated with adjustable support members (see  FIG. 3  of the prior Maglev patents, supra), from materials and damage resulting from the assembly operations taking place on top of the rigid bars  3 . 
         [0006]    The frame  1  may be used in connection with the adjustable support members  3  and rigid bars  2  without the presence of the surface  2 , whereby the apparatus would perform the method of assembly in the same manner. The structures to be assembled are not required to, and preferably do not, rest on the surface  2  but rather on the tops of the rigid bars  3 ; this is readily depicted in  FIG. 1 , which shows a magnetic levitation guideway guide plate  5  positioned on the tops of the rigid bars  3 . 
         [0007]    The rigid bars  3  are typically parallel to each other and set apart from each other by a fixed distance (e.g., one foot apart). Other applications and particularly complex or curved contours may require more rigid bars  3  closer together. In some circumstances, the rigid bars  3  would not necessarily need to be parallel to each other. Some applications would not require as many rigid bars  3  such that the rigid bars  3  could be placed more than one foot apart. The skilled artisan is credited with the ability to ascertain any such requirements that such applications may require with respect to such spacing. 
       SUMMARY OF THE INVENTION 
       [0008]    Broadly contemplated herein, in accordance with at least one embodiment of the invention, are arrangements and processes for clamping a large workpiece such as an I-beam to a precision assembly table (or fitup table) or other workpiece support. Particularly contemplated herein, in accordance with at least one embodiment of the invention, are clamping arrangements that can be employed with fitup arms or other mounting arrangements for accommodating large workpieces such as I-beams. 
         [0009]    Assembling a beam (e.g., an I-beam), including welding portions thereof, can be a complex process. It is important to be able to hold a beam securely and accurately during an assembly process. 
         [0010]    In accordance with at least one embodiment of the invention, are arrangements and processes for clamping a large workpiece including a base; a first track supported by the base; a first slider for sliding along the track; a second slider for sliding along the first track, wherein the first slider and the second slider are moveable relative to one another along the first track; a first spacer supported by the first slider; and a second spacer supported by the second slider; wherein the first spacer and the second spacer are adapted to grip the workpiece therebetween. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of a precision assembly table with basic components thereof according to the prior art. 
           [0012]      FIG. 2  is a perspective view of a clamping arrangement that may be employed with a fitup arm or other suitable support arrangement in accordance with an embodiment of the invention. 
           [0013]      FIG. 3  shows essentially the same arrangement as in  FIG. 2 , but in a different perspective view. 
           [0014]      FIG. 4  shows a clamping arrangement, in accordance with an embodiment of the invention, as applied to an I-beam in a generally horizontal orientation (as opposed to the generally vertical orientation shown in  FIGS. 2 and 3 ). 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0015]    The disclosure now turns to  FIGS. 2-4  in connection with embodiments of the invention.  FIGS. 2-4  may henceforth be referred to collectively if not otherwise noted. In  FIG. 2  various components are labeled; it should be understood that a label in  FIG. 2  may be construed as referring to any similar component in  FIG. 2  as well. Components in  FIGS. 3 and 4  which are similarly configured or positioned as in  FIG. 2  can also be taken as being referenced by labels from  FIG. 2 . 
         [0016]      FIGS. 2-4  also specifically depict a workpiece in the form of an I-beam  10  (e.g., as may be employed in highway, bridge or other construction projects). However, it should be understood that embodiments of the invention as broadly contemplated herein may be considered as being applicable to a very wide variety of large workpieces other than I-beams. Accordingly, specific references to I-beams herethroughout should not be construed as necessarily limiting upon the embodiments of the invention. 
         [0017]      FIG. 2  illustrates in perspective view a clamping arrangement  12  in accordance with an embodiment of the invention that may be employed with a suitable support arrangement such as the one shown in  FIG. 1 . Shown are two cooperating sides of a clamp structure on each of two different base/track combinations, flanking an I-beam  10 . 
         [0018]    As shown, two parallel bases  14  (which themselves could correspond to fitup table arms as understood herein) may each support corresponding tracks  16  on which are disposed two sliders  18  each, wherein the sliders  18  can move towards and away from each other along the track  16 . To this end, each slider  18  may have wheels or other similarly functioning elements  20  permitting such movement with respect to the track  16 . Each slider  18  can selectively be fixed in position with respect to the track  16  via any suitable arrangement such as motion locks  22  as shown. Wherein, e.g., four pivotable elements per slider  18  may pivot with respect to each slider  18  such that in a first position of each motion lock  22 , e.g., a horizontal position, the motion lock  22  serves to hold a corresponding portion of the slider  18  in place with respect to the track  16  while in a second position of each motion lock  22 , e.g., a vertical position, the motion lock  22  releases a corresponding portion of the slider  18  from the track  16  to permit, with other motion locks  22  so positioned, the slider  18  to slide along the track  16 . 
         [0019]    Each slider  18  preferably has a gripper  24  configured for holding a side spacer  26 . Each side spacer  26 , as shown, may preferably have holes  28  in it so as to reduce heat conduction therethrough (e.g., if the I-beam  10  is to be welded or otherwise undergo a high-temperature treatment). Whereas the grippers  24  each preferably have a major dimension oriented perpendicularly with respect to a longitudinal axis of the corresponding track  16 , the side spacers  26  preferably have a major dimension oriented in parallel to a longitudinal axis of the corresponding track  16 . 
         [0020]    As shown, cooperating pairs of sliders  18  (one pair per track  16 ) can preferably flank a lower (horizontal) portion of the I-beam  10  (that is to be worked on or assembled) and thus serve to hold that lower portion of the I-beam in place. Accordingly, a corresponding side spacer  26  may preferably be configured and dimensioned as to provide additional support to the vertical portion of the I-beam  10 . 
         [0021]    In order to provide fine positional adjustment of the sliders  18  with respect to the I-beam  10 , an adjusting cylinder  30  (e.g., hydraulic cylinder) may preferably be provided for each slider  18  to cause each slider  18  to undergo limited displacement so as to finely position each slider  18  and/or ensure that each slider  18  is sufficiently brought into contact with the I-beam  10  as to adequately provide support for the I-beam  10 . These cylinders  30  may travel with the sliders  18 , to then be fixed with respect to the track  16  so as then be able to apply a force relative to the sliders  18 , or they may each be selectively insertable into and mountable with respect to the track  16  as needed, or they may each be already fixedly mounted with respect to the track  16  in a manner to selectively accommodate a slider  18  to push a slider  18  when needed. 
         [0022]    As shown, each slider  18  preferably includes a lower post  32  support configured for accommodating an interchangeable post  34  therein. The interchangeable posts  34  can be of essentially any suitable length so as to accommodate an I-beam  10  in accordance with applications broadly contemplated herein.  FIGS. 2 and 3  relate to an I-beam  10  in vertical orientation, so the discussion at present will be directed the use of interchangeable posts  34  for such an orientation. 
         [0023]    As shown, with respect to each track  16 , two such interchangeable posts  34  may preferably extend upwardly from corresponding lower post  32  supports to upper post supports  36 . These upper post supports  36  are each preferably integrated with horizontal lintel supports  38  configured for supporting an interchangeable horizontal support or lintel  40 . Again, the interchangeable lintels  40  can be of essentially any suitable width so as to accommodate an I-beam  10  in accordance with applications broadly contemplated herein. (While only one set of interchangeable posts  34  and an interchangeable lintel  40  is shown in each of  FIGS. 2 and 3 , it should be understood that a similarly configured set can preferably be provided with respect to the other track  16 .) 
         [0024]    The interchangeable lintels  40  preferably serve to support an I-beam  10  at an upper portion of an I-beam  10  in a manner now to be discussed. As shown, a pair of sliding holders  42  may preferably be disposed on the upper (horizontal) portion of an I-beam  10 . These sliding holders  42  preferably employ wheels or other suitable elements  44  to slidably displace with respect to the upper portion of the I-beam  10 , along a direction parallel to a longitudinal axis of the upper portion of the I-beam  10 . At each interchangeable lintel  40 , a variable spacer  46  may preferably be provided to extend and provide support between the interchangeable lintel  40  and the sliding holder  42 , all by way of exerting a downward force on the I-beam  10  to better support the I-beam  10  (in conjunction with the sliders  18  and associated components below). Preferably, the variable spacer  46  may include a hydraulic cylinder  48  to assist the spacer in extending between the lintel  40  and the sliding holder  42 , thereby not only assisting in support of the I-beam  10  but to also provide fine positional adjustment of the sliding holder  42  against the I-beam  10 . 
         [0025]      FIG. 4  shows a clamping arrangement  112 , in accordance with an embodiment of the invention, as applied to an I-beam  110  in a generally horizontal orientation (as opposed to the generally vertical orientation shown in  FIGS. 2 and 3  and with similar elements having reference numeral advanced by  100  with respect to reference numeral used in  FIGS. 2 and 3 ). Thus, essentially the same clamping arrangement as  FIGS. 2  and  3  is shown, but with components differently configured. As shown in  FIG. 4 , a much longer lintel  140  is provided, while the interchangeable posts are removed. Preferably, the upper  136  and lower  132  post supports will be configured for readily integrating or mating with one another or may be configured for accommodating an interchangeable internal support therewithin, such as a rod that extends from an interior of the lower post support upwardly into an interior of the upper post support. It can also be seen in  FIG. 4  that smaller spacers  126 , different from than the ones shown in  FIGS. 2 and 3  can be gripped by the grippers  124  and used for supporting the I-beam  110 . Also shown are intermediate supports  150  that can selectively be placed on a track  116  to support the large horizontal portion of the I-beam. It can also be seen that here there is no support, analogous to the variable spacer of  FIGS. 2 and 3 , extending downwardly from the lintel. 
         [0026]    In general overview, to the extent that any specific dimensions may appear in one or more drawings, it should be understood that these are provided merely by way of illustrative and non-restrictive example, and are not necessarily to be construed as limiting upon the embodiments of the invention. The same holds true for any relative or proportional dimensions that can be discerned from the drawings. 
         [0027]    Without further analysis, the foregoing will so fully reveal the gist of the invention and its embodiments that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute characteristics of the generic or specific aspects of the invention and its embodiments. 
         [0028]    If not otherwise stated herein, it may be assumed that all components and/or processes described heretofore may, if appropriate, be considered to be interchangeable with similar components and/or processes disclosed elsewhere in the specification, unless an express indication is made to the contrary. 
         [0029]    If not otherwise stated herein, it may be assumed that all components and/or processes described heretofore may, if appropriate, be considered to be interchangeable with similar components and/or processes disclosed elsewhere in the specification, unless an express indication is made to the contrary. 
         [0030]    If not otherwise stated herein, any and all patents, patent publications, articles and other printed publications discussed or mentioned herein are hereby incorporated by reference as if set forth in their entirety herein. 
         [0031]    It should be appreciated that the apparatus and method of the invention may be configured and conducted as appropriate for any context at hand. The embodiments described above are to be considered in all respects only as illustrative and not restrictive.