Abstract:
A tool adjustment system includes a first body, a second body and an adjusting member. The adjusting member is rotatably affixed to the first body and allowed to rotate in the second body during angular adjustment of the first body relative to the second body. In yet another aspect of the present invention, an adjustment tool and a locking tool are provided.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION 
     This invention relates generally to an adjustment system and more particularly to a member for adjusting a tool relative to a mounting body. 
     Powered grippers, clamps and gauges (collectively referenced herein as a gripper or tool) are typically secured to a floor mounted bracket, table, robotic arm or other mounting body by common dowel pins, roll pins or bolts. Conventional dowel pins have a circular-cylindrical exterior shape, a chamfered first end, a rounded second end and are entirely solid. These dowel pins, roll pins and bolts serve to positively locate and fasten the gripper to the adjacent bracket in a positive and precise manner in the X, Y and Z directional axes. In one traditional arrangement, a pair of solid dowel pins are pressfit into a bracket and powered gripper, with the dowel pins being diagonally located relative to each other. In this device, a pair of mounting screws are also diagonally located relative to each other for securing the powered gripper to the mounting bracket. However, the dowel pins and screws are positioned to define a square pattern. The dowel pins and screws do not allow for angular realignment between the gripper and bracket. 
     Notwithstanding, it is common for the workpiece to be mislocated by as much as 15 angular minutes prior to being clamped by the gripper; this mislocation can be significant for a large part, such as a sheet metal automotive vehicle body panel. This can lead to subsequent gripping misalignment and undesired process variations. The conventional manner for readjusting the gripper to account for part misalignment is to insert multiple shims or wedges to angularly move the bracket along the X (vertical) and Y (horizontal in-out) planes. Thus, gripper to bracket setup and maintenance are often time-consuming, expensive and relatively crude. 
     In accordance with the present invention, a preferred embodiment of a tool adjustment system includes a first body, a second body and adjustable locating member. The member is rotatably affixed to the first body and allowed to rotate in the second body during angular adjustment of the bodies relative to each other. In another aspect of the present invention, a pin longitudinally projects in an offset manner from a generally smooth intermediate section of a rotatable adjustment member. In still another aspect of the present invention, a plug is inserted into the rotatable adjustment member so as to expand and deter further rotation of the rotatable adjustment member and a tool body relative to a mounting member. In yet another aspect of the present invention, an adjustment tool and a locking tool serve to rotate the rotatable adjustment member in order to adjust the tool body relative to the mounting member and then subsequently maintain the desired adjustment position while locking the rotatable adjustment member to the mounting member. 
     The adjustable tool mounting system of the present invention is advantageous over conventional devices in that the present invention provides a very refined and precise rotational adjustment of a gripper body relative to a bracket. This accurate adjustment construction allows for quick and precisely maintained positioning of the gripper body, thereby saving the associated setup and maintenance costs while improving repeatable part gripping and subsequent processing. The present invention also allows for use of a rotatable adjustment assembly as a retro-fit kit in existing tool setups. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side elevational view showing the preferred embodiment of a tool adjustment system of the present invention relative to a workpiece; 
     FIG. 2 is an enlarged side elevational view, taken within circle  2  of FIG. 1, showing the preferred embodiment of the tool adjustment system; 
     FIG. 3 is a cross sectional view, taken along line  3 — 3  of FIG. 2, showing the preferred embodiment of the tool adjustment system; 
     FIG. 3A is a cross sectional view, taken along line  3 A— 3 A, showing the interface between an adjustable dowel and an insert employed in the preferred embodiment of the tool adjustment system; 
     FIG. 4 is an exploded perspective view showing the adjustable dowel, insert and a plug employed in the preferred embodiment of the tool adjustment system; 
     FIG. 5 is a side elevational view showing the insert employed in the preferred embodiment of the tool adjustment system; 
     FIG. 6 is an end elevational view showing the insert employed in the preferred embodiment of the tool adjustment system; 
     FIG. 7 is a side elevational view showing the adjustable dowel employed in the preferred embodiment of the tool adjustment system; 
     FIG. 8 is an end elevational view showing the adjustable dowel employed in the preferred embodiment of the tool adjustment system; 
     FIG. 9 is an end elevational view, taken opposite that of FIG. 8, showing the adjustable dowel employed in the preferred embodiment of the tool adjustment system; 
     FIG. 10 is a partially fragmented side elevational view showing a first alternate embodiment of the tool adjustment system; 
     FIG. 11 is an exploded perspective view showing the first alternate embodiment of the tool adjustment system; 
     FIG. 12 is an exploded perspective view showing a second alternate embodiment of the tool adjustment system; and 
     FIG. 13 is a side elevational view, similar to that of FIG. 2, showing a third alternate embodiment of the tool adjustment system. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1-3, a first body or bracket  21  has a base  23  secured to a floor or table  25  by a couple of bolts  27  and a couple of locating dowel pins  29 . An angled blade  31  projects from an upstanding riser  33  of bracket  21 . Four through bores  41  are drilled in blade  31  and are arranged in a square pattern relative to each other. 
     A gripper tool  43  has an aluminum body  45  containing a pneumatic or hydraulic fluid powered piston which travels in a linear direction. An externally mounted gripping or back up arm  47  is adjustably mounted for rotation to a hub. Within body  45 , hub is rotatably coupled to a crank which, in turn, is coupled to a linearly moving slide by a straight link. Four holes  49  are drilled into body  45  corresponding to through bores  41 . Gripper  43  is preferably a TRILOK™ gripper sold by BTM Corporation employing an internally moving three point, crank-to-slide block stop. It is also envisioned that any other gripper, or tool can be employed in combination with the present invention. For example, the preferred gripper may be substituted by the devices shown in the following U.S. patents which have been invented by one of the inventors of the present invention: U.S. Pat. No. 5,516,173 entitled “Gripper” which issued on May 14, 1996; U.S. Pat. No. 5,171,001 entitled “Sealed Power Clamp” which issued on Dec. 15, 1992; and U.S. Pat. No. 5,118,088 entitled “Power Clamp” which issued on Jun. 2, 1992; all of which are incorporated by reference herein. A second bracket  51  and second powered gripper  53  are also used to grip a workpiece  55 , such as a piece of sheet metal, against a gripping pad  57  secured to arm  47  of the first gripper  43 . 
     The preferred embodiment of an adjustable tool mounting system  71 , is used to adjust then fasten gripper body  45  to bracket  21 . This can be observed in FIGS. 3-6. An adjustable dowel assembly  73  employs an insert  75  machined from 4150 heat treated steel rod stock, having a black oxide coating, and a partially circular-cylindrical exterior surface  77 . The exterior surface at a body end  79  of insert  75  has a straight knurl or splined pattern oriented in a parallel and longitudinal direction. A pair of partially circular cross sectionally shaped legs  81  longitudinally project from body end  79  and are separated by a rectangularly shaped slot defined by a pair of flat internal surfaces  83 . Insert  75  is pressfit into one hole  49  in gripper body  45  and is prevented from rotation by engagement of the straight knurl pattern with the surface of body  45  defining hole  49 . 
     Insert  75  is ideally suited for retrofit use in existing circular-cylindrical holes commonly employed in gripper bodies, that do not allow for angular adjustment relative to a corresponding mounting bracket. Accordingly, flat surfaces  83  of legs  81  act as interlocking structures for engaging an adjustable dowel, as will be discussed in further detail hereinafter. Notwithstanding, it should be appreciated that other interlocking structures may be employed which are integrally formed as part of the gripper body such that a separate insert is not necessarily required. 
     Referring now to FIGS. 3,  3 A,  4  and  7 - 9 , the adjustable dowel  101  has a head  103 , a body portion or an intermediate segment  105 , and an adjusting portion or a pin  107 . Head  103  has a hexagonally shaped periphery defined by multiple flats for receiving a hand-held adjustable wrench. Intermediate segment  105  has an unthreaded, circular-cylindrical and smooth exterior surface which is longitudinally elongated. An expansion slot  109  is machined through a portion of intermediate segment  105  and head  103 . Pin  107  also has an unthreaded and smooth, circular-cylindrical exterior surface. A centerline of pin  107  is eccentrically or transversely offset from intermediate segment  105 . Thus, a transverse width of pin  107  is less than a transverse width of intermediate segment  105 . Adjustable dowel  101  is preferably machined from 4150 heat treated steel rod stock having a black oxide coating and a Rockwell hardness of  28 - 32  C. 
     Pin  107  of adjustable dowel  101  is longitudinally insertable through bore  41  of bracket  21  and into hole  49  of gripper body  45  such that its circular-cylindrical external surface fits between legs  81  of insert  75 . Concurrently, intermediate segment  105  of adjustable dowel  101  is inserted and allowed to freely rotate within bore  41  of bracket  21 . Thus, when a wrench engages and rotates head  103  of adjustable dowel  101 , intermediate segment  105  will rotate within bracket  21  and eccentric pin  107  will abut against and be prevented from rotating relative to flat surfaces  83  of insert  75 . This will cause gripper body  45  to pivot about a fixed pivot dowel  121  (see FIGS.  1  and  2 ), which has a solid circular-cylindrical body with rounded or chamfered ends. Plus or minus 0.5 degrees of rotational adjustment will provide the equivalent amount of angular adjustment of gripping pad  57  (see FIG. 1) depending on the specific geometry of the parts employed. 
     Next, as is illustrated in FIGS. 3 and 4, an externally threaded and tapered steel plug  124  is inserted into a corresponding internally threaded cavity  124  of adjustable dowel  101 . This causes a portion of adjustable dowel  101 , adjacent to expansion slot  109 , to transversely expand away from its longitudinal centerline, thereby securely fastening and preventing adjustable dowel  101  from further rotation relative to bracket  21 . Plug  123  has a blind hexagonal hole for receiving an Allen wrench but may also be provided with a slot or Phillips head pattern for engagement by a screwdriver. The wrench must continue to engage and prevent head  103  of adjustable dowel  101  from rotating while plug  123  is being fully inserted, so as to maintain gripper body  45  in its final desired adjusted position. 
     A pair of mounting screws or bolts  125  (see FIGS. 1 and 2) are then screwed into their corresponding smooth bracket bores and internally threaded gripper body holes to longitudinally secure gripper body  45  to bracket  21 . However, between approximately 0.8 and 1 millimeter of transverse clearance is provided between each screw  125  and the corresponding bracket bore to allow for the rotational adjustment provided by adjustment dowel  101 . 
     A first alternate embodiment adjustable tool mounting system of the present invention is shown in FIGS. 10 and 11. An insert  201  and adjustable dowel  203  are generally the same as that described with the preferred embodiment except that in the present embodiment, a tool receiving head  205  has a width less than that of an intermediate section  207 . Furthermore, head  205  has a pair of external flat surfaces  209 . Thus, adjustable dowel  203  can be entirely hidden within a bracket  211  if the thickness of bracket  211  is larger than the longitudinal length of adjustable dowel  203 . 
     In this arrangement, a special steel adjustment tool  221  is used to rotate adjustable dowel  203 . An engaging end  223  of adjustment tool  221  has a pair of internal flats  225  separated by a generally rectangular transverse slot for receiving head  205 . Adjustment tool  221  is further provided with a wrench receiving end  231 , defined by a hexagonal periphery. A wrench  234  engages end  231  of adjustment tool  221  for rotating adjustable dowel  203  relative to bracket  211 . After a gripper  233  has been angularly oriented to its desired position relative to bracket  211 , wrench  234  maintains adjustment tool  221  and adjustable dowel  203  in its final position while an Allen wrench  241  is longitudinally inserted into an internal and cylindrical shaft  243  running through adjustment tool  221 . This allows Allen wrench  241  to engage the blind hexagonal hole of a plug  245 . Thus, Allen wrench  241  is allowed to rotate plug  245  in order to expand the intermediate section of adjustable dowel  203  without causing concurrent rotation of adjustable dowel  203  or gripper  233 . Alternately, a screwdriver can be used in place of Allen wrench  241 . 
     FIG. 12 illustrates a second alternate embodiment of the present invention wherein a special adjustment tool  271  has an internal, blind hexagonal configuration  273  for engaging a corresponding external, hexagonal pattern  275  on an adjustable dowel  277 . Furthermore, the opposite end of adjustment tool  271  is provided with a set of transversely extending holes  279  for receiving a steel rod  281 . Rod  281  has stepped, circular-cylindrical external surfaces which are coaxially aligned. The smaller portion  283  of rod  281  is engagable into holes  279  and used to manually rotate adjustment tool  271  and adjustable dowel  277 . 
     Finally, referring to FIG. 13, two adjustable dowels  301  (and no pivot dowels) are employed to provide full circular rotational adjustment of the gripper relative to the mounting bracket. Hence, the theoretical gripper pivot point is located between the two adjustable dowels  301 . In this situation, the adjustable dowels are essentially identical to each other. 
     While various embodiments of the tool adjustment system have been described and illustrated, it will be appreciated that many other variations can be used without departing from the scope of the present invention. For example, an impacted wedge can be used in place of the disclosed plug. Furthermore, the interlocking structure may include a keyhole-shaped gripper hole or other internally formed gripper body projections. Moreover, the pin of the adjustable dowel may have other shapes. Various materials have been disclosed in an exemplary fashion, however, other materials may of course be employed. It is intended by the following claims to cover these and any other departures from the disclosed embodiments which fall within the true spirit of this invention.