Patent Publication Number: US-9421599-B2

Title: Clinch clamp

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/414,229, filed on Nov. 16, 2010. The entire disclosure of the above application is incorporated herein by reference. 
    
    
     BACKGROUND AND SUMMARY 
     The present invention relates generally to a joint forming apparatus and more specifically to a die and punch and related method for forming a joint between sheets of material. 
     In the manufacture of products, there is often a need to join a pair or several pieces of material, such as sheet metal to build various assemblies and subassemblies. There are many different means for accomplishing this joining task. For example, there is adhesive bonding, welding or cold deformation. Both bonding and welding processes require the introduction of a foreign material to the assembly. The foreign material can tend to fail, thereby weakening the assembly. In cold deformation, several pieces of sheet material are plastically deformed in such a manner that they are locked together. Depending on the thickness, strength and/or the number of pieces of material to be joined, a great amount of force is required to accomplish this task. 
     Traditional presses for providing this force include in-line hydraulic presses and accordion-type toggle presses. Such presses, however, are often heavy and include many intricate parts making maintenance difficult and time consuming. Furthermore, many presses require a robot to feed (such as horizontally) the pieces of material into a position between a die and punch. Moreover, in many instances it can become difficult and inefficient to manage and accommodate the associated rotational and translational movements of the various components in the press. 
     In accordance with the present invention, a clamping apparatus is provided. The apparatus generally includes a clamp body, an arm, a punch, a die and a first linear actuator. The arm is rotatably fixed to the clamp body around a first pivot axis between a closed position and an open position. The punch is mounted to one of the body and the arm. The die is fixedly mounted to the other of the body and the arm. The first linear actuator includes a rod that is rotatably coupled to the arm around a second pivot axis. The rod moves between a first position corresponding to the arm being in the closed position and a second position corresponding to the arm being in the open position. A first distance is defined between the first and second pivot axes in the closed position. A second distance is defined between the first and second pivot axes in the open position. The first and second distances are equivalent. 
     According to additional features of the present invention, the first linear actuator is rotatably fixed to the body about a third pivot axis. The linear actuator rotates around the third pivot axis during translation of the rod between the first and second positions. The arm generally comprises an arcuate body having a first body portion that extends between a first end and the first pivot axis and a second body portion that extends between the second end and the first pivot axis. The first end of the first arm includes one of the punch and die. The second end of the arm includes an engagement member that is configured to contact a portion of the clamp body when the arm rotates to the closed position. 
     According to additional aspects of the present invention, a second linear actuator is provided on the clamp body. The second linear actuator includes a movable member that moves between a retracted position and an extended position. In the extended position, the movable member is aligned for contact with the second end of the arm and inhibits rotation of the arm around the first pivot axis toward the open position during operation of the punch. 
     A method for clinching a workpiece with a clamping apparatus is provided. The clamping apparatus is moved to an open position. The workpiece is located between a punch and die oppositely mounted to a clamp body and an arm, respectively, of the clamping apparatus. A rod of a first linear actuator is actuated from a first position to a second position. The arm is caused to rotate relative to the clamp body around a first pivot axis and into a closed position. The rod is rotatably coupled to the arm around a second pivot axis. A first distance is defined between a first and second pivot axes in the closed position and a second distance is defined between the first and second axes in the open position. The first and second distances are equivalent. The punch is then actuated. 
     According to other aspects of the present invention, the method further comprises contacting an engagement member disposed on the arm with a stop disposed on the clamp body upon rotation of the arm into the closed position. Actuating the rod further comprises rotating the first linear actuator relative to the body about a third pivot axis. According to other aspects of the present invention, the method further comprises actuating a second linear actuator from a first position to a second position causing a movable member to become aligned for contact with the arm prior to actuating the punch. The movable member engages and inhibits rotation of the arm around the first pivot axis toward the open position upon actuation of the punch. 
     According to other aspects of the present invention, the clamping apparatus is advantageous over conventional clamping devices. In this regard, the clamping apparatus according to the present invention provides a lower cost clamping configuration that requires less moving parts compared to other conventional clamping devices that may incorporate a camming action between a track and follower associated with the arm. Furthermore, the clamping apparatus of the present invention provides a swing arm that rotates around a pivot pin to an open position that allows vertical insertion of workpieces onto the die. The swing arm has a counterbalance body portion that extends opposite the pivot pin relative to the punch assembly to improve balance of the swing arm relative to the clamp body. The configuration of the swing arm, clamp body and first actuator provide an apparatus that accommodates higher loads and has improved balance as compared to conventional clamping devices. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a clinch clamp constructed in accordance with the principles of the present invention and shown with the clinch clamp in an open position; 
         FIG. 2  is a perspective view of the clinch clamp of  FIG. 1  and shown with the clinch clamp in the closed position; 
         FIG. 3  is a side view of the clinch clamp of  FIG. 2  shown in a work position; 
         FIG. 4  is a top view of the clinch clamp of  FIG. 2 ; 
         FIG. 5  is a front view of the clinch clamp of  FIG. 2 ; 
         FIG. 6  is a side view of the clinch clamp of  FIG. 1  and shown with a lockout key in a retracted position; 
         FIG. 7  is a side view of the clinch clamp of  FIG. 3  and shown in a closed position with the lockout key in an extended position; 
         FIG. 8  is a cross-sectional view taken along lines  8 - 8  of  FIG. 4 ; 
         FIG. 9  is a side view of a clinch clamp constructed in accordance with additional features of the present invention and shown with the clinch clamp in a closed position and shown with the punch in an actuated position; 
         FIG. 10  is a top view of the clinch clamp of  FIG. 9 ; 
         FIG. 11  is a front view of the clinch clamp of  FIG. 9 ; 
         FIG. 12  is a side view of the clinch clamp of  FIG. 9  and shown with the clinch clamp in the open position and with a lockout key in a retracted position; 
         FIG. 13  is a cross-sectional view of the clinch clamp of  FIG. 9  and shown with the punch in a retracted position; 
         FIG. 14  is a perspective view of a clinch clamp constructed in accordance with additional principles of the present invention and incorporating an anti-rotation feature, the clinch clamp shown in a closed position; 
         FIG. 15  is a cross-sectional view taken along lines  15 - 15  of  FIG. 14 ; 
         FIG. 16  is a front perspective view of the anti-rotation feature of the clinch clamp of  FIG. 14 ; 
         FIG. 17  is a bottom side perspective view of the anti-rotation feature of the clinch clamp of  FIG. 14 ; 
         FIG. 18  is a cross-sectional view taken along lines  18 - 18  of  FIG. 15 ; 
         FIG. 19  is a perspective view of a clinch clamp constructed with additional principles of the present invention and shown in an open position; and 
         FIG. 20  is a perspective view of the clinch clamp of  FIG. 19  and shown in a closed, working position. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     The following description of the preferred embodiment is merely exemplary in nature and is in no way intended to limit the scope of the invention, its application, or its uses. 
     With initial reference to  FIGS. 1 and 2 , an apparatus for clinching a workpiece constructed in accordance to the present invention is shown and generally identified at reference numeral  10 . The apparatus  10  is preferably a clinch-type clamp. The apparatus  10  generally includes a body assembly  12 , a punch assembly  14 , a die assembly  16  and a first linear actuator  20 . The body assembly  12  generally comprises a clamp body  22  having a pair of support arms  24  that support a swing arm  26 . The body assembly  12  is fixedly mounted to a clamp base  28 . The swing arm  26  is rotatably fixed to the clamp body  22  around a pivot pin  30  for rotation around an arm pivot axis  32 . It can be appreciated that while the illustrated embodiment comprises support arms  24  that are bifurcated for supporting a single swing arm  26  therebetween, the clamp body  22  can alternatively comprise a single riser having a bifurcated swing arm pivotally mounted thereto. 
     The punch assembly  14  generally comprises a punch holder  36 , a punch  38 , a biasing member  40  (see also  FIG. 8 ), and a stripper  42 . The punch assembly  14  is mounted to the swing arm  26  by a cylinder mounting block  44 . A punch cylinder  46  and actuator  48  are mounted against the cylinder mounting block  44 . The actuator  48  is hydraulically actuated however other configurations, such as pneumatic and mechanical are contemplated. The biasing member  40  provides clamping force to the stripper  42 . 
     The die assembly  16  is fixedly mounted to the support arms  24  by a die support  50 . The die assembly  16  generally includes a die body  52  and an anvil  54  ( FIG. 6 ). The die assembly  16  further includes three movable die blades  56 . While not specifically identified by reference numeral in the figures, the die assembly  16  further includes a guard, a canted coil spring, a dowel and a bolt. Further description of the die assembly  16  may be found in commonly owned U.S. Pat. Nos. 6,115,898; 6,092,270; and 5,581,860, which are expressly incorporated herein by reference. 
     With further reference now to  FIGS. 3-7 , the first linear actuator  20  will be further described. The first linear actuator  20  generally includes a piston  60  that translates through a cylinder  62 . The first linear actuator  20  is a pneumatically actuated cylinder however other configurations, such as hydraulic and mechanical are contemplated. The piston  60  is fixedly connected to a piston rod  64 . As will become appreciated from the following discussion, the piston rod  64  translates between a first position (or extended position), illustrated in  FIG. 3 , corresponding to the swing arm  26  being in a closed position to a second position (or retracted position), illustrated in  FIG. 6 , corresponding to the swing arm  26  being in an open position. The first linear actuator  20  further includes a lower end cap  70  and an upper end cap  72  connected at opposite ends of the cylinder  62  and further supported by four tie rods  74 . The first linear actuator  20  is rotatably coupled to the clamp body  22  through a trunion mount  78 . Explained further, the first linear actuator  20  is rotatably coupled through a cylinder pivot pin  80  extending through the trunion mount  78  for rotation around a cylinder pivot axis  82  ( FIG. 1 ). A distal end  86  of the piston rod  64  includes a piston rod pivot joint  90 . The piston rod pivot joint  90  generally includes a rod eye  92 , a bushing  94 , a piston rod pivot pin  96  and a piston rod mount  98 . As viewed in  FIG. 2 , the piston rod mount  98  generally includes a clevis  100  having a first leg  102  and a second leg  104 . The rod eye  92  is rotatably mounted around the piston rod pivot pin  96 . The bushing  94  is interposed between the pivot pin  96  and the rod eye  92 . The bushing  94  according to the present invention is constructed of bronze. The bronze bushing  94  provides favorable wear properties in the present application. The piston rod pivot pin  96  defines a pivot pin axis  110  through which the piston rod mount  98  and therefore the swing arm  26  rotates about. 
     With specific reference now to  FIGS. 3 and 6-8 , additional features of the apparatus  10  will be described. A second linear actuator  120  is mounted generally between the support arms  24  of the clamp body  22 . The second linear actuator  120  is a pneumatically actuated cylinder however other configurations, such as hydraulic and mechanical are contemplated. The second linear actuator  120  generally includes a piston  122  that is configured for slidable translation within a cylinder  124 . The piston  122  carries a rod  126  that has a lock-out key  130  disposed on a distal end  132  thereof. The second linear actuator  120  is configured to translate the lock-out key  130  between an extended position ( FIGS. 3, 7 and 8 ) and a retracted position ( FIG. 6 ). As will become appreciated from the following discussion, the lock-out key  130  is configured to move to the expanded position subsequent to the swing arm  26  being rotated to the closed position to engage the swing arm  26  and inhibit rotation of the swing arm  26  in a counterclockwise direction around the swing arm pivot pin  30  during actuation of the punch  38 . Subsequent to a punching event (e.g., clinching of a workpiece), the lock-out key  130  is retracted, such that the swing arm  26  is uninhibited from rotating in a counterclockwise direction around the pivot pin  30  as viewed in  FIG. 3  to the open position as shown in  FIG. 6 . 
     With specific reference now to  FIGS. 6 and 8 , additional features of the apparatus  10  will be further described. An engagement member  136  is disposed on the swing arm  26 . The engagement member  136  is configured to contact a hard stop  140  that is fixedly connected between the support arms  24  of the clamp body  22 . Contact of the engagement member  136  onto the hard stop  140  facilitates the stopping of clockwise rotation of the swing arm  26  around the arm pivot axis  32  when rotating from the open position ( FIG. 6 ) to the closed position ( FIG. 8 ). As can be appreciated, the hard stop  140  can assist in dissipating the rotational stopping energy of the swing arm  26  that could otherwise be taken up by the piston rod pivot joint  90 . The engagement member  136  can be formed of urethane or rubber. The hard stop  140  can be formed of metal, such as steel or other hard material. 
     The apparatus  10  according to the present invention incorporates components that are arranged for rotational and translational movement that are without any joints that require a cam or track configuration. In this regard, a more robust, efficient and repeatable motion of the swing arm  26  between the open position ( FIG. 1 ) and the closed position ( FIG. 2 ) is provided. To further illustrate a geometrical relationship provided by the body assembly  12  and first linear actuator  20 , specific reference now is made to  FIGS. 3 and 6 . A first distance D 1  is defined between the axis  32  of the swing arm pivot pin  30  and the axis  110  of the piston rod pivot pin  96 . The distance D 1  is illustrated in  FIG. 3  with the swing arm  26  in the closed position. A distance D 2  is defined between the axis  32  of the swing arm pivot pin  30  and the axis  110  of the piston rod pivot pin  96  with the swing arm  26  in the open position. The distances D 1  and D 2  are equivalent. Furthermore, the distance between the axis  32  of the swing arm pivot pin  30  and the axis  110  of the piston rod pivot pin  96  remains unchanged throughout the rotational motion of the swing arm  26  between the closed position ( FIG. 3 ) and open position ( FIG. 6 ). 
     With particular reference to  FIG. 6 , the swing arm  26  will be described in greater detail. The swing arm  26  generally comprises an arcuate or C-shaped body  150  including a first body portion  152  and a second body portion  154 . The first body portion  152  extends between a first end  160  of the swing arm  26  and the axis  32  of the swing arm pivot pin  30 . The second body portion  154  extends between a second end  162  of the swing arm  26  and the axis  32  of the swing arm pivot pin  30 . According to an advantage of the present invention, the second body portion  154  of the swing arm  26  has a significant amount of mass opposite the first body portion  152  relative to the axis  32 . In one example, the first body portion  152  can account for at least one-quarter of the mass of the swing arm  26 . In this regard, the second body portion  154  can provide a counter balance to the mass associated with the first body portion  152  (and also the mass associated with the components of the punch assembly  14 ). 
     The apparatus  10  according to the present invention provides other useful advantages. Notably, with the swing arm  26  rotated to the open position as illustrated in  FIG. 6 , the immediate space above and adjacent to the die assembly  16  is unobstructed. Explained further, a longitudinal axis  168  taken through the die body  52  with the swing arm  26  rotated to the open position is non-intersecting relative to the punch assembly  14 . In this regard, if desired, a user (a robot, etc.) is able to horizontally locate a workpiece (specifically identified at reference numeral  170  in  FIG. 8 ) against the die body  52  with reduced effort as compared to introducing a workpiece that may require additional and/or more complicated movements, such as translating horizontally and/or rotating. 
     An exemplary method of using the apparatus  10  according to the present invention will now be described. At the outset, the body assembly  12  is rotated to the open position ( FIGS. 1 and 6 ). A workpiece (identified at reference numeral  170  in  FIG. 8 ) is then located generally against the die assembly  16 . The first linear actuator  20  is then actuated, such that the piston rod  64  translates from the retracted position illustrated in  FIG. 6  to the expanded position illustrated in  FIG. 3 . During the actuation of the piston rod  64 , the cylinder  62  of the first linear actuator  20  is caused to rotate around the cylinder pivot axis  82  in a direction counterclockwise as viewed in the figures relative to the cylinder pivot pin  80  of the trunion mount  78 . Concurrently, the piston rod mount  98  is caused to rotate clockwise around the axis  110  of the piston rod pivot pin  96 . During rotational movement of the cylinder  62  relative to the trunion mount  78 , the lower end cap  70  simply rotates uninhibited in a direction away from the clamp body  22 . Rotation of the piston rod mount  98  around the axis  110  causes the swing arm  26  to rotate in a direction clockwise (as view in  FIG. 6 ) around the swing arm pivot pin  30  until the engagement member  136  disposed on the second end  162  of the swing arm  26  engages the hard stop  140  disposed on the clamp body  22  ( FIG. 8 ). 
     At this point, the swing arm  26  is in the closed position as shown in  FIGS. 3, 7 and 8 . Next, the second linear actuator  120  is actuated causing the rod  126  and lock-out key  130  to move from the position shown in  FIG. 6  to the position shown in  FIG. 8 . The lock-out key  130  is now in position to resist any counterclockwise rotation of the swing arm  26  about the pivot axis  32  that is caused from firing of the punch  38 . With the lock-out key  130  expanded to the position shown in  FIG. 8 , the punch  38  can then be actuated creating a clinch joint on the workpiece  170 . The punch  38  is linearly actuated in a direction along the longitudinal axis  168  ( FIG. 6 ). Again, a backlash force that may tend to influence the swing arm  26  to rotate in a counterclockwise direction around the pivot axis  32  resulting from engagement of the punch  38  onto the workpiece  170  can be blocked by the lock-out key  130 . Once the clinch joint has been made, the punch  38  is then retracted by the cylinder  46 . The second linear actuator  120  is then retracted, such that the rod  126  translates back into the cylinder  124  to a position where the lock-out key  130  clears the second end  162  of the swing arm  26  ( FIG. 6 ). 
     The first linear actuator  20  is then actuated, such that the piston rod  64  retracts into the cylinder  62  causing the piston rod mount  98  to rotate in a counterclockwise direction around the axis  110  of the piston rod pivot pin  96 . Concurrently, the cylinder  62  rotates in a clockwise direction around the cylinder pivot axis  82  ( FIG. 1 ). As can be appreciated, the swing arm  26  is therefore caused to rotate in a counterclockwise direction around the axis  32  of the swing arm pivot pin  30  until reaching the open position shown in  FIG. 6 . The method then repeats for successive clinching operations. 
     With reference now to  FIGS. 9-13 , an apparatus for clinching a workpiece constructed in accordance to additional features of the present invention is shown and generally identified at reference numeral  210 . The apparatus  210  is preferably a clinch-type clamp. The apparatus  210  generally includes a body assembly  212 , a punch assembly  214 , a die assembly  216  and a first linear actuator  220 . The body assembly  212  generally comprises a clamp body  222  having a pair of support arms  224  ( FIG. 10 ) that support a swing arm  226 . The body assembly  212  is fixedly mounted to a clamp base  228 . The swing arm  226  is rotatably fixed to the clamp body  222  around a pivot pin  230  for rotation about an arm pivot axis  232 . It will be appreciated that while the illustrated embodiment comprises support arms  224  that are bifurcated for supporting a single swing arm  226  therebetween, the clamp body  222  can alternatively comprise a single riser having a bifurcated swing arm pivotally mounted thereto. 
     The punch assembly  214  generally comprises a punch holder  236 , a punch  238 , a biasing member  240  and a stripper  242 . The punch assembly  214  is mounted to the swing arm  226  by a cylinder mounting block  244 . A punch cylinder  246  and an actuator  248  are mounted against the cylinder mounting block  244 . The actuator  248  is an air/oil intensifying cylinder however, other configurations, such as pneumatic and mechanical are contemplated. The biasing member  240  provides a clamping force to the stripper  242 . 
     The die assembly  216  is fixedly mounted to the support arms  224  by a die support  250 . The die assembly  216  can have any configuration such as one that includes three movable die blades as discussed above with respect to the die assembly  16 . Other configurations are contemplated. 
     With reference now to  FIGS. 9, 12, and 13 , the first linear actuator  220  will be further described. The first linear actuator  220  generally includes a piston  260  that translates through a cylinder  262 . The first linear actuator  220  is a pneumatically actuated cylinder however, other configurations, such as hydraulic and mechanical are contemplated. The piston  260  is fixedly connected to a piston rod  264 . As will become appreciated from the following discussion, the piston rod  264  translates between a first position (or extended position), illustrated in  FIGS. 9 and 13 , corresponding to the swing arm  226  being in a closed position to a second position (or retracted position), illustrated in  FIG. 12 , corresponding to the swing arm  226  being in an open position. The first linear actuator  220  is rotatably coupled to the clamp body  222  through a trunion mount  278 . The first linear actuator  220  is rotatably coupled through a cylinder pivot pin  280  extending through the trunion mount  278  for rotation about a cylinder pivot axis  282  ( FIG. 12 ). A distal end  286  of the piston rod  264  includes a piston rod pivot joint  290 . The piston rod pivot joint  290  generally includes a rod eye  292  ( FIG. 9 ), a bushing  294 , a piston rod pivot pin  296 , and a piston rod mount  298 . The piston rod pivot joint  290  may be configured similarly to the piston rod pivot joint  90  described above with respect to  FIGS. 3-7 . The piston rod pivot pin  296  defines a pivot pin axis  299  through which the piston rod mount  298  and, therefore the swing arm  226  rotates about. 
     The linear actuator  220  remains at a non-orthogonal angle relative to the clamp base  228  in both the closed position ( FIG. 9 ) and the open position ( FIG. 12 ). Such a relationship allows an increase in throat depth, identified at area  300  ( FIG. 15 ). 
     A second linear actuator  320  is mounted generally between the support arms  224  of the clamp body  222 . The second linear actuator  320  is a pneumatically actuated cylinder however, other configurations, such as hydraulic and mechanical are contemplated. The second linear actuator  320  generally includes a piston  322  that is configured for slidable translation within a cylinder  324 . The piston  322  carries a rod  326  that has a lock-out key  330  disposed on a distal end  332  thereof. The second linear actuator  320  is configured to translate the lock-out key  330  between an extended position ( FIGS. 9 and 13 ) and a retracted position ( FIG. 12 ). The lock-out key  330  is configured to move to the expanded position subsequent to the swing arm  226  being rotated to the closed position to engage the swing arm  226  and inhibit rotation of the swing arm  226  in a counterclockwise direction around the swing arm pivot pin  230  during actuation of the punch  238 . The lock-out key  330  can operate similar to the lock-out key  130  described above. In this regard, subsequent to a punching event, the lock-out key  330  is retracted, such that the swing arm  226  is uninhibited from rotating in a counterclockwise direction around the pivot pin  230  as viewed in  FIG. 9  to the open position as shown in  FIG. 12 . The second linear actuator  320  is also arranged at a non-orthogonal angle relative the clamp base  228  to align with the swing arm  226 . 
     An engagement member  336  ( FIG. 13 ) is disposed on the swing arm  226 . The engagement member  336  is configured to contact a hard stop  340  that is fixedly connected between the support arms  224  of the clamp body  222 . The configuration of the engagement member  336  and the hard stop  340  is similar to that described above with respect to the engagement member  136  and  140 . In this regard, the engagement member  336  is configured to engage the hard stop  340  to facilitate the stopping of clockwise rotation of the swing arm  226  around the arm pivot axis  232  when rotating from the open position ( FIG. 12 ) to the closed position ( FIG. 13 ). The hard stop  340  can assist in dissipating the rotational stopping energy of the swing arm  226  that could otherwise be taken up by the piston rod pivot joint  290 . 
     As with the apparatus  10  described above, the apparatus  210  according to the present invention incorporates components that are arranged for rotational and translational movement that are without any joints that require a cam or track configuration. In this regard, a more robust, efficient, and repeatable motion of the swing arm  226  between the open position ( FIG. 12 ) and the closed position ( FIGS. 9 and 13 ) is provided. To further illustrate a geometrical relationship provided by the body assembly  212  and the first linear actuator  220 , specific reference now is made to the  FIGS. 9 and 12 . A first distance D 3  is defined between the axis  232  of the swing arm pivot pin  230  and the axis  299  of the piston rod pivot pin  296 . The distance D 3  is illustrated in  FIG. 9  with the swing arm  226  in the closed position. A distance D 4  is defined between the axis  232  of the swing arm pivot pin  230  and the axis  299  of the piston rod pivot pin  296  with the swing arm  226  in the open position. The distances D 3  and D 4  are equivalent. Furthermore, the distance between the axis  232  of the swing arm pivot pin  230  and the axis  299  of the piston rod pivot pin  296  remains unchanged throughout the rotational motion of the swing arm  226  between the closed position ( FIGS. 9 and 13 ) and the open position ( FIG. 12 ). 
     With particular reference now to  FIG. 13 , the swing arm  226  will be described in greater detail. The swing arm  226  generally comprises an arcuate or C-shaped body  350  including a first body portion  352  and a second body portion  354 . The first body portion  352  extends between a first end  360  of the swing arm  226  and the axis  232  of the swing arm pivot pin  230 . The second body portion  354  extends between a second end  362  of the swing arm  226  and the axis  232  of the swing arm pivot pin  230 . Similar to the swing arm configuration described above with respect to the swing arm  26 , the swing arm  226  incorporates a significant amount of mass on the second body portion  354  opposite the first body portion  352  relative to the axis  232 . In one example, the first body portion  352  can account for at least one-quarter of the mass of the swing arm  226 . In this regard, the second body portion  354  can provide a counter balance to the mass associated with the first body portion  352  (and also the mass associated with the components of the punch assembly  214 ). In addition, when the swing arm  226  is rotated to the open position as illustrated in  FIG. 12 , the immediate space above and adjacent to the die assembly  216  is unobstructed. 
     An exemplary method of using the apparatus  210  according to the present invention will now be described. At the outset, the body assembly  212  is rotated to the open position ( FIG. 12 ). A workpiece (not specifically shown) may be generally located against the die assembly  216 . The first linear actuator  220  is then actuated, such that the piston rod  264  translates from the retracted position illustrated in  FIG. 12  to the expanded position illustrated in  FIG. 13 . During the actuation of the piston rod  264 , the cylinder  262  of the first linear actuator  220  is caused to rotate around the cylinder pivot axis  282  ( FIG. 12 ) in a direction counterclockwise as viewed in the Figures relative to the cylinder pivot pin  280  of the trunion mount  278 . Concurrently, the piston rod mount  298  is caused to rotate clockwise around the axis  299  of the piston rod pivot pin  296 . During rotation of the piston rod mount  298  around the axis  299  causes the swing arm  226  to rotate in a direction clockwise (as viewed in  FIG. 12 ) around the swing arm pivot pin  230  until the engagement member  336  ( FIG. 13 ) disposed on the second end  362  of the swing arm  226  engages the hard stop  340  disposed on the clamp body  222 . At this point, the swing arm  226  is in the closed position as illustrated in  FIG. 9 . Next, the second linear actuator  320  is actuated causing the rod  326  and the lock-out key  330  to move from the position shown in  FIG. 12  (retracted position) to the position shown in  FIG. 13  (actuated position). The lock-out key  330  is now in position to resist any counterclockwise rotation of the swing arm  226  about the pivot axis  232  that is caused from firing of the punch  238 . 
     With the lock-out key  330  expanded to the position shown in  FIG. 13 , the punch  238  can then be actuated from the position shown in  FIG. 13  to the position shown in  FIG. 9 . Again, a backlash force that may tend to influence the swing arm  226  to rotate in a counterclockwise direction around the pivot axis  232  resulting from the engagement of the punch  238  onto a workpiece can be blocked by the lock-out key  330 . Once the clinch joint has been made, the punch  238  is then retracted by the cylinder  246 . The second linear actuator  320  is then retracted, such that the rod  326  translates back into the cylinder  324  to a position where the lock-out key  330  clears the second end  362  of the swing arm  226  ( FIG. 12 ). The first linear actuator  220  is then actuated, such that the piston rod  264  retracts into the cylinder  262  causing the piston rod mount  298  to rotate in a counterclockwise direction around the axis  299  of the piston rod pivot pin  296 . Concurrently, the cylinder  262  rotates in a clockwise direction around the cylinder pivot axis  282  ( FIG. 12 ). As can be appreciated, the swing arm  226  is therefore caused to rotate in a counterclockwise direction around the axis  232  of the swing arm pivot pin  230  until reaching the open position shown in  FIG. 12 . The method then repeats for successive clinching operations. 
     With reference now to  FIGS. 14-18 , an apparatus for clinching a workpiece constructed in accordance to additional features of the present invention is shown and generally identified at reference numeral  410 . The apparatus  410  is preferably a clinch-type clamp. The apparatus  410  generally includes a body assembly  412 , a die assembly  416 , and a first linear actuator  420 . The apparatus  410  is constructed substantially similar to the apparatus  210  described above and shown in  FIGS. 9-13 , however the apparatus  410  incorporates an anti-rotation feature  430 . The following discussion will be directed toward features associated with the anti-rotation feature  430 . A description of the remainder of the apparatus  410  may be found above with the description of the apparatus  210  and will not be repeated here. The anti-rotation feature  430  generally includes an anti-rotation block  432 , an anti-rotation key  434 , and a punch  440 . The anti-rotation block  432  is rigidly secured to a support block  444  that is coupled to a swing arm  426  with a fastener  450 . The anti-rotation block  432  is coupled to the support block  444  by way of fasteners  452 . The anti-rotation block  432  incorporates opposing flats  456  ( FIG. 18 ) that are configured to slidably engage complementary flats  460  formed on the punch  440 . 
     The anti-rotation key  434  is coupled to the punch  440  by way of a fastener  468 . The anti-rotation feature  430  is configured to cooperate with a punch assembly  470  that generally comprises a punch holder  472 , the punch  440 , a biasing member  474  and a stripper  476 . The punch assembly  470  is mounted to the swing arm  426  by a cylinder mounting block  478  and the support block  444 . A punch cylinder  480  and an actuator  482  are mounted against the cylinder mounting block  478 . The respective flats  456  of the anti-rotation block  432  and flats  460  of the punch  440  maintain a fixed rotational orientation of the punch  440  and punch assembly  470  as a whole. It will be appreciated that the anti-rotation feature  430  may also be incorporated on the apparatus  10  described above with respect to  FIGS. 1-8 . 
     With reference now to  FIGS. 19 and 20 , an apparatus for clinching a workpiece constructed in accordance to additional features of the present invention is shown and generally identified at reference numeral  510 . The apparatus  510  is preferably a clinch-type clamp. The apparatus  510  generally includes a body assembly  512 , a die assembly  516 , and a first linear actuator  520 . The apparatus  510  is constructed substantially similar to the apparatuses  10  and  210  described above, however the apparatus  510  incorporates a locater arm assembly  530  and a locater pin mount assembly  532 . The body assembly  512  comprises a clamp body  533  having a pair of support arms  534  that support a swing arm  535 . The first linear actuator  520  is configured to be arranged similar to the actuator  20  in that the first linear actuator  520  attains a substantially vertical orientation relative to a clamp base  536  in the closed position ( FIG. 20 ). The following discussion will be directed toward features associated with the locater arm assembly  530  and locater pin mount assembly  532 . A description of the remainder of the apparatus  510  may be found above with the description of the apparatus  10  and the apparatus  210  and will not be repeated here. 
     The locater arm assembly  530  generally includes a pair of upper mounting blocks  540  that are configured to be fixedly mounted to the swing arm  535 . In other examples, the mounting blocks  540  can be additionally or alternatively fixedly mounted to the cylinder mounting block  544 . A punch assembly  546  can extend from the mounting block  544 . A corresponding pair of locating arms  548  extends from the upper mounting blocks  540  and extends generally on opposing sides of the punch assembly  546 . The locating arms  548  define terminal workpiece engaging surfaces  550 . As will be described herein, the terminal workpiece engaging surfaces  550  of the locating arms  548  are configured to engage and therefore position a workpiece collectively referred to at  560 . The workpiece  560  can generally include any workpieces that are to be joined such as a first workpiece  562  and a second workpiece  564  as shown in  FIG. 20 . 
     The locater pin mount assembly  532  generally includes a pair of lower mounting blocks  566  that are fixedly mounted relative to a die support  568 . A die body  570  can be mounted to the die support  568 . A pair of mounting arms  572  extends from the lower mounting blocks  566  and includes a corresponding pair of locater pins  576  extending generally upright therefrom. The locater pins  576  can include a generally conical and pointed tip  578 . The locater pins  576  extend generally on opposing sides of the die body  570 . 
     In the closed and working configuration shown in  FIG. 20 , the conical portions  578  of the locater pins  576  can be configured to extend through corresponding apertures formed in the first workpiece  562  and second workpiece  564 . The terminal workpiece engaging surfaces  550  of the respective locating arms  548  can engage the second (or upper) workpiece  564  to permit the proper geometric orientation of a single workpiece or multiple workpieces during a joining operation. The locating pins  576  can be accurately positioned at desired locations on the workpiece  560  such as with a laser to qualify the apparatus  510  as a gauge such that the first and second workpieces  562  and  564  can be properly aligned to each other or to another subassembly. It will be appreciated that the locater arm assembly  530  and/or the locater pin mount assembly  532  can be configured as part of any of the other clinch-type clamp apparatuses  10 ,  210 , and  410  described above. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.