Abstract:
A tooling apparatus for positioning end effector tooling for engagement with a workpiece to facilitate the performance of work operations on the workpiece. The apparatus includes an elongated rectangular tubular backbone member, a plurality of tubular collars positioned over and secured to the backbone member at predetermined longitudinally spaced locations along the backbone member, and a plurality of support structures secured to a side of one or more of the collars utilizing a plurality of fasteners engaging apertures in the collars and aligned apertures in the underlying backbone member.

Description:
[0001]     The present application claims priority to U.S. Provisional Application No. 60/696,865 filed Jul. 6, 2005. entitled APPARATUS FOR ACCURATELY POSITIONING AND SUPPORTING MODULAR TOOLING. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to an apparatus for accurately positioning and supporting modular tooling, and more particularly, an apparatus that provides a wide range of fine adjustment and rigid support for modular tooling to ensure accurate geometric positioning of a workpiece during machining and/or assembling of the workpiece.  
       BACKGROUND OF THE INVENTION  
       [0003]     The assembling and/or welding of various workpieces is often a challenging task in the manufacturing industry. For example, in the automotive industry, sheet metal stampings must often be welded together in order to create a single assembled or preassembled part. Prior to welding the sheet metal stampings, the stampings must be positioned in a highly accurate and repetitive geometric position in order that the sheet metal stampings may be accurately welded into an assembled position. Failure to do so may lead to the improper sizing and positioning of the assembled workpiece relative to the remaining parts of the automobile. The positioning of the sheet metal stampings prior to welding is often referred to as the geometric positioning of the workpiece.  
         [0004]     In order to maintain the geometric positioning of the workpiece, previous designs have utilized heavy, rigid, structural members that are supported and moved by manipulators, such as robotic arms. These structural members are typically fabricated from heavy-duty steel so as to ensure the integrity and positioning of the end effector tooling that is mounted thereon. Such end effector tooling may include various power clamps, power grippers, and/or pin locators to locate and secure the workpiece in a predetermined geometric position. The adjustability and/or flexibility of the positioning and movement of the end effector tooling has been limited in such previous designs, as the previous designs typically concentrate on the rigidity and accuracy of the end effector tooling. This is to ensure that if the end effector tooling were to come into contact with something other than the workpiece, the end effector tooling will not be compromised, but rather, the end effector tooling will maintain the geometric positioning necessary to weld and assemble accurate workpieces.  
         [0005]     The disadvantage to such previous designs is that they are typically heavy and non-flexible in design. Thus, the manipulator or robotic arm must be large and powerful enough to support and move such heavy tooling. In addition, the lack of flexibility does not allow for a high degree of adjustability to the end effector tooling such that the end effector tooling may be adjusted for a variety of different workpieces. The inability of such designs to adapt to various workpiece designs requires that the end effector tooling be dedicated to the specific configuration of one particular workpiece. This requires that a multitude of tooling be purchased and provided thereby creating an undesirable inefficiency in the industry.  
         [0006]     It would be desirable to provide lightweight, flexible tooling that provided for the accurate positioning and support of end effector tooling to ensure the geometric positioning of a variety of workpieces during the machining and/or assembling of the workpiece.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention relates to an apparatus for accurately positioning, adjusting, and supporting end effector tooling to ensure the geometric positioning of a workpiece during the machining and/or assembling of the workpiece. The apparatus provides a rigid support member connectable to a manipulator, such as a robotic arm. A plurality of coupling members are connected to the rigid support member in predetermined positions. At least one support member is adjustably connected to at least one of the coupling members wherein the support members are adaptable to receive the end effector tooling in a predetermined geometric position.  
         [0008]     According to an important feature of the invention, the apparatus includes an elongated tubular backbone member of polygonal cross-section, a plurality of annular collars having a polygonal cross-section corresponding to the polygonal cross-section of the backbone member positioned over and secured to the backbone member at spaced locations along the backbone member, a plurality of support structures secured to a side of one or more collars, and a plurality of fasteners adapted to secure the support structures to the collars.  
         [0009]     According to a further feature of the invention, the fasteners engage apertures in the collars and aligned apertures in the underlying backbone member.  
         [0010]     According to a further feature of the invention, the apertures in the collars and the underlying backbone member comprise threaded apertures for receipt of threaded fasteners and unthreaded apertures for receipt of dowel pins.  
         [0011]     According to a further feature of the invention, the apertures are aligned in rows with each row including a pair of outboard threaded apertures for receipt of outboard threaded fasteners and a central unthreaded aperture for receipt of a central dowel pin.  
         [0012]     According to a further feature of the invention, the support structure defines an outwardly opening socket.  
         [0013]     According to a further feature of the invention, the apparatus further includes a tubular boom rod telescopically received at its inboard end in the outwardly opening socket.  
         [0014]     According to a further feature of the invention, the apparatus further includes a coupling including a socket portion telescopically receiving the outboard end of the boom rod and a mounting surface mounting a respective end effector tool.  
         [0015]     According to a further feature of the invention, the coupling includes a base member defining the socket portion and a mounting plate defining the mounting surface.  
         [0016]     According to a further feature of the invention, the base member and the mounting plate are adjustably interconnected.  
         [0017]     According to a further feature of the invention, the adjustable interconnection between the base member and the mounting plate comprises a series of parallel grooves on one of the base member and the mounting plate and a series of coacting parallel ribs on the other of the base member and the mounting plate.  
         [0018]     According to a further feature of the invention, the support structures include a support plate secured to one or more collars and a socket member secured to the support plate.  
         [0019]     The invention also provides a methodology for forming a tooling apparatus for positioning end effector tooling.  
         [0020]     According to the invention methodology, a tubular backbone member of polygonal cross sectional configuration is provided; a plurality of collars are positioned over the backbone member at predetermined longitudinally spaced locations; the collars are secured to the backbone member; the collars and backbone member are machined to provide a plurality of aligned apertures in the collars and in the underlying backbone member; a plurality of support structures are provided for supporting the end effector tooling; and the support structures are secured to the collars utilizing fasteners engaging the aligned apertures in the collars and in the underlying backbone member.  
         [0021]     According to a further feature of the invention methodology, at least certain of the aligned apertures are threaded and the fasteners comprise threaded fasteners.  
         [0022]     According to a further feature of the invention methodology, at least certain of the aligned apertures are unthreaded and the fasteners comprise dowel pins.  
         [0023]     According to a further feature of the invention methodology, each support structure defines an outwardly opening socket and the method includes the further steps of positioning the inboard end of a boom rod in each socket, mounting a coupling member on the outboard end of each boom rod, and mounting an end effector tool on the coupling member. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]     The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout several view and wherein:  
         [0025]      FIG. 1  is a perspective view of the apparatus of the present invention being utilized to clamp and position two sheet metal workpieces;  
         [0026]      FIG. 2  is a perspective view of the apparatus of the present invention clamping and positioning a sheet metal workpiece;  
         [0027]      FIG. 3  is a perspective view showing the apparatus of the present invention locating and clamping two sheet metal pieces;  
         [0028]      FIG. 4  is a perspective view of the apparatus of the present invention in another configuration;  
         [0029]      FIG. 5  is a front plan view of a rigid support member of the apparatus of the present invention;  
         [0030]      FIG. 6  is a perspective view showing the rigid support member, the coupling members, and the support member of the apparatus of the present invention;  
         [0031]      FIG. 7  is a perspective view showing an adjustable support member of the apparatus of the present invention; and  
         [0032]      FIG. 8  is a cross-sectional view taken on line  8 - 8  of  FIG. 5 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0033]     Referring to the drawings, the present invention will now be described in detail with reference to the disclosed embodiment.  
         [0034]      FIGS. 1-8  illustrate an apparatus  10  for accurately positioning and supporting a workpiece  12  or workpieces  12 , such as stamped sheet metal parts, in a predetermined geometric position so that certain machining and assembling operations may be performed on the workpiece  12 .  
         [0035]     The apparatus  10  includes a rigid support member or backbone member  14  that is connectable to a manipulator, such as a robotic arm (not shown). The backbone member  14  has a plurality of annular coupling or collar members  16  mounted thereon in predetermined longitudinally spaced positions. A mounting plate  18  may be connected to a pair of collar members  16  whereby the manipulator or robotic arm is connected via the mounting plate  18  to the backbone member  14 . A plurality of support structures  20  are connected to at least one of the collar members  16  in predetermined positions. The support structures  20  support end effector tools  22 , such as a power clamps, power grippers, and/or a locator pins. The apparatus  10  provides accurate positioning of the end effector tools  22  so as to accurately and repeatably position the workpieces  12  in a predetermined geometric position so that a particular machining or assembling operation, such as welding, may be performed on the workpieces  12 . Such geometric positioning may hold tolerances up to + or −0.25 mm  
         [0036]     In order to provide the apparatus  10  with the appropriate rigidity and support, the backbone member  14  is fabricated from a substantially rectangular, hollow tubular structure having rounded corners thereon. The backbone member  14  is fabricated from a lightweight, high-strength rigid material, such as carbon fiber, steel, castings, aluminum, or other lightweight, high-strength, rigid materials. The backbone member  14  is fabricated in a high-precision manner such that the backbone member  14  may maintain a high degree of accuracy.  
         [0037]     The collar members  16  are mounted on the outside surface of the backbone member  14 . The collar members  16  are substantially rectangular and hollow so as to receive the backbone member  14 . The collar members  16  are also fabricated from a lightweight, high-strength material, similar to that provided for the backbone member  14 . The collar members  16  are fixedly secured to the backbone member  14  by bonding or welding. However, it is anticipated that other securing means may be utilized such as expanding the backbone member  14  onto the collar members  16  when the backbone member is fabricated from a carbon fiber material.  
         [0038]     Following securement of the collar members  16  on the backbone member  14  in predetermined longitudinally spaced positions, six apertures, formed as two parallel rows, are machined in each of the four sides of each collar member and in the underlying backbone member for receiving dowel rods  33  and threaded fasteners  32  from the support structures  20 . The central apertures  24   a  on each row on each side of the collar member  16 , as well as the aligned central apertures  14   a  in backbone member  14 , are unthreaded and receive a dowel rod  33 , and the outboard apertures  24   b  in each row on each side of the collar member  36 , as well as the aligned outboard apertures  14   b  in backbone member  14 , are threaded for receiving threaded fasteners  32 . Each of the four sides of the collar members  16  may also have a recessed portion  26  for reducing the amount of material and weight associated with the collar members  16 . Again, the collar members  16  are fabricated in a high-precision manner so as to maintain a high degree of accuracy when mounting the end effector tooling  22  thereon.  
         [0039]     Alternatively, and as seen in  FIGS. 4 and 7 , each collar member  16  may have a single row of apertures  24   a,    24   b  on each side thereof for aligned coaction with a single row of apertures in the underlying backbone member  14 .  
         [0040]     Various support structures  20  may be utilized to connect the end effector tooling  22  to the collar members  16 . In one support structure embodiment, seen in  FIGS. 1, 3  and  6 , the support structure includes a support plate  28  connected to and extending between a pair of collar members  16 , as best seen in  FIG. 6 . The support plate  28  may be connected at each end to any of the four sides of the collar members  16 . The support plate  28  has a substantially rectangular, plate-like configuration with rounded corners. A plurality of unthreaded outboard counterbore apertures  30   a  extend through the support plate  28  for receiving headed threaded fasteners  32  for engagement with threaded apertures  24   b  in a side face of the collar members and aligned threaded apertures  14   b  in the backbone member, and a plurality of unthreaded central constant diameter apertures  30   b  extend though the support plate for receiving locating dowel rods  33  for receipt in unthreaded central apertures  24   a  in a side face of the collar members and aligned unthreaded central apertures  14   a  in the backbone member. The threaded fasteners  32  serve to rigidly mount the support plate  28  on the collar members  16  and the dowel rods  33  provide a high degree of locational accuracy in the positioning of the plate on the collar members. The support plate  28  further includes a plurality of spaced rows of apertures with each row including a pair of threaded outboard apertures  30   c  and an unthreaded central apertures  30   d.  The support plate  28  is manufactured in a highly precise manner and may be fabricated from a low weight, high strength rigid material similar to that provided for the rigid support member  14 . The support plate  28  allows for adjustment of the end effector tooling  22  along a longitudinal axis of the backbone member  14 .  
         [0041]     The support structure  20  of the embodiment of  FIGS. 1, 3  and  6  also includes a socket member  34  that is connected directly to the support plate  28  by the use of conventional fasteners  32  engaging threaded outboard apertures  30   c  and locating dowel rods  33  engaging unthreaded central apertures  30   d.    
         [0042]     In an alternate embodiment of support structure  20 , as seen in  FIGS. 2 and 7 , the support structure  20  may comprise a unitary member  35  including a rectangular base portion  35   a  and a rectangular socket portion  35   b.  Base portion  35   a  includes outboard apertures  35   c  extending therethrough for receiving conventional fasteners  32  for threaded engagement with outboard collar apertures  24   b  and outboard backbone apertures  14   b  and central constant diameter apertures  35   d  for receiving dowel rods  33  for receipt in unthreaded central collar apertures  24   a  and unthreaded central backbone apertures  14   a.  Rib portions  34   e  extend integrally from the base portion  35   a  and the tubular portion  35   b  to provide added support to the tubular portion  35   b.  Unitary member  35  is manufactured in a highly precise manner and may be fabricated from a low weight, high strength rigid material similar to that provided for the rigid support member  14 .  
         [0043]     In a further alternate embodiment of the support structure  20 , seen at  64  in  FIG. 2 , the support structure includes a base plate portion  64   a  secured to a side face of a collar and a U-shaped tubular socket portion  64   b.    
         [0044]     The positioning apparatus of the invention further includes a plurality of boom rods  36 . Each boom rod  36  is substantially rectangular and hollow and includes rounded corners. Each boom rod  36  is telescopically received at its inboard end in a socket column member  34 , in a socket portion  35   b  of a unitary member  35 , or in the “U” shaped socket portion  64   b  of a support structure  64 , and may be fixedly secured to the member  34 , socket portion  35   b,  or socket portion  64   b  by bonding or welding. Each boom rod  36  is also manufactured in a highly precise manner and fabricated from a light weight, high strength rigid material as previously described for the rigid support member  14 .  
         [0045]     As best seen in  FIGS. 4 and 7 , each effector tooling  22  is supported on the outboard end of a boom rod  36  through the use of an adjustable coupling. Several variations of adjustable couplings are illustrated. One form of adjustable coupling is seen at  38  in  FIGS. 4 and 7  and includes a base member  42  and an adjustable mounting plate  43 .  
         [0046]     Base member  42  includes a substantially rectangular tubular portion  42   a  for telescopically receiving the outboard end of a boom rod  36  and a base portion  42   b  which is integral with the tubular portion  42   a.  The base portion  42   b  provides a substantially flat mounting surface having contoured parallel grooves  42   c  formed therein. A pair of spaced substantially parallel slots  42   d  extend through the base portion  42   b  of the base member  42  at right angles to the grooves  42   c.    
         [0047]     Each adjustable mounting plate  43  is coupled to the base portion  42   b  of a base member  42 . The adjustable mounting plate  43  has an L-shaped configuration including a webbed portion  58  extending integrally between a long leg portion  60  and a short leg portion  62 . The short leg portion  62  has a contoured ribbed surface  64  formed on the bottom thereof for matingly engaging the grooves  42   c  on the base portion  42   b  of the base member  42  whereby to adjustably mount the mounting plate on the base member. A pair of apertures extend through the short leg portion  62  of the mounting plate  43  and align with the slots  42   d  in the base portion  42   b  of the base member  42 . A pair of conventional fasteners  50  extend through the apertures in the leg portion  62  and through the slots  42   d,  and a nut  66  is provided on the threaded end of the fasteners  50  to tighten the mounting plate  43  on the base member  42  in any desired position of lateral adjustment. Indicia  68  are provided on an edge of the base portion  42   b  of the base member  42  so as to indicate the position of the adjustable mounting plate  43  relative to the base member. Each adjustable coupling  38  is manufactured in a highly precise manner and fabricated from similar materials as the rigid support member  14 .  
         [0048]     Each end effector tooling  22  is mounted on an adjustable mounting plate  43  utilizing apertures extending through the adjustable mounting plate which correspondingly align with apertures provided in the end effector tooling  22 . Conventional fasteners extend through the apertures in the adjustable mounting plate  43  and into the apertures provided in the end effector tooling  28  to secure the end effector tooling  22  to the adjustable mounting plate  43 . As previously noted, various end effector tooling  22  may be utilized, such as power grippers, power clamps, locator pins, etc.  
         [0049]     In operation, the apparatus  10  is typically set up prior to connecting the apparatus  10  to a manipulator or a robotic arm. The end effector tooling  22  is adjusted with respect to the apparatus  10  so as to provide proper geometric positioning of the workpiece  12 . The end effector tooling  22  may be adjusted by moving and/or adjusting the collar members  16  with respect to the backbone member  14  and by adjusting support structures  20  with respect to collar members  16 . The length of the boom rods  36  may also be adjusted to provide further adjustment to the end effector tooling  22 . The adjustable mounting plate  43  also provides varied adjustment of the end effector tooling  22 . Further, as seen at  70  in  FIG. 2 , combinations of boom rods and couplings may be utilized to allow the mounting structure for the end effector tooling to include right angles or elbows.  
         [0050]     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments, but to the contrary, it is intended to cover various modifications or equivalent arrangements included within the spirit and scope of the appended claims. The scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is performed under the law.