Abstract:
A pin clamp assembly has a housing, an actuating device and a movable locating pin. A clamping device is coupled with the actuating device to move within the locator pin. The clamping device includes a rod and a finger. The finger extends and retracts in and out of the locating pin to enable the locating pin and clamping device to be moved so that the clamping finger clamps a workpiece.

Description:
FIELD 
       [0001]    The present disclosure relates to a pin clamp and, more specifically, to a pin clamp with a retractable clamp assembly. 
       BACKGROUND 
       [0002]    Pin clamp assemblies have been known for numerous years in robotic and manufacturing applications. Pin clamp assemblies may be used with a robot end effector to clamp a workpiece or material at a specific workstation such that an operation can be performed on the workpiece. The pin assembly can utilize a movable locator pin coupled with a clamping mechanism to clamp to the workpiece. A number of movable locator pin assemblies are available in the art. However, the operating mechanism for moving locator pin and the clamping mechanism are very complicated. The prior art requires bent rods and cams to control the extension and retraction of the clamping fingers. The bent rods are driven by various cams and the like to accomplish the requested movement. The present disclosure provides the art with a simple mechanism to drive the locator pin and the clamping mechanism. 
         [0003]    Accordingly, the present disclosure provides the art with a simple mechanism to move the locator pin and extend and retract the clamping finger. The present disclosure provides a linear movement from an actuator to extend and retract the clamping fingers and drive the locator pin. 
       SUMMARY 
       [0004]    According to the disclosure, a pin clamp assembly comprises a housing with a cavity in the housing and a bore extending from the cavity through the housing wall. An actuating device is coupled with the housing. A movable locating pin is positioned in the housing bore. The locating pin includes an internal bore and at least one aperture through the locator pin wall to the bore. A clamping device is coupled with the actuating device. The clamping device includes a movable rod positioned in the pin locator bore and at least one finger. The finger is located in the locator pin aperture and is coupled with the rod. A member extends from the rod or the finger. A slot is formed on the rod or the finger to receive the extending member. Reciprocation of the rod in the locator bore moves the at least one finger, in the locator pin aperture, between an extended and a retracted position. In the extended position, the rod moves the locator pin and the at least one finger into a clamping position. The rod includes an annular flange that moves in an enlarged bore portion of the locator pin. The rod includes the extending member with a tapered surface. The rod includes a flat planar head with the extending tapered surface on one side. A piston rod extension couples between the rod and the actuator device. The piston rod extension is positioned in the housing cavity and threadedly secured on the piston rod. A stop is positioned in the enlarged bore portion of the locator pin to contact the rod flange. An anti-rotation device is coupled with the locator pin to prohibit rotation of the locator pin. 
         [0005]    Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0006]    The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
           [0007]      FIG. 1  is a perspective view of the pin clamp assembly. 
           [0008]      FIG. 2  is a cross-section of  FIG. 1  in the first position. 
           [0009]      FIG. 3  is the same view as  FIG. 2  in a second position. 
           [0010]      FIG. 4  is the same view as  FIG. 2  in a third position. 
           [0011]      FIG. 5  is a perspective view of a locator pin rod. 
           [0012]      FIG. 6  is a perspective view of a clamping finger. 
           [0013]      FIG. 7  is a cross-section of a second embodiment of the pin clamp. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Example embodiments will now be described more fully with reference to the accompanying drawings. 
         [0015]    Turning to  FIG. 1 , a pin clamping assembly is illustrated and designated with the reference numeral  10 . The pin clamping assembly includes a housing  12  and an actuator  14 . The actuator device  14  is illustrated as an oval shaped piston cylinder including diagonally mounted studs  16  attaching it to the housing  12 . Also, a conduit  17  provides fluid to the piston cylinder. However, a round piston cylinder, either pneumatic or hydraulic, as well as an electrical actuator could be used. 
         [0016]    The actuating mechanism includes a piston assembly  16  positioned inside of the actuating cylinder  18 . The piston assembly  16  includes a piston rod  20  and a pair of pistons  22 ,  24 . The fluid acts on piston  22  moving both pistons  22 ,  24  in a first or downward direction as illustrated in the figures. Piston  24  is locked onto a detent  26  when the piston  24  reaches a bottom dead center position. This locks the piston rod  20  in position. Fluid enters below the second piston  24  returning both of the pistons in a second direction to their first position. 
         [0017]    The housing  12  includes an adapter  28  secured to an end of the housing  12 . The adapter  28  has an overall cylindrical configuration with a through bore  30 . The through bore  30  has an enlarged bore portion  31 . The enlarged bore portion  31  receives a cylindrical portion  46  of the locator pin  40 . The adapter  28  includes at least one anti-rotation mechanism  33  that are positioned in bores  35 . The anti-rotation mechanism  33  includes a housing with a spring biased detent ball. The ball contacts the locator pin  40  to prohibit rotation of the locator pin  40 . The housing  12  includes a cavity  32  that receives the piston rod extension  34 . The piston rod extension  34  is connected at one end, via a threaded connection, with the piston rod  20 . The other end includes an annular cut out to receive the clamping mechanism rod  54 . 
         [0018]    A locator pin  40  is positioned within the adapter  28 . The locator pin  40  houses a clamping mechanism  50 . 
         [0019]    The locator pin  40  has an elongated cylindrical shape with a central bore  42 . The central bore  42  includes an enlarged portion  44  at one end of the locator pin  40 . At least one aperture  45  is formed in the wall of the locator pin  40  that extends radially into the central bore  42 . The locator pin outer circumferential surface includes at least one cut out  47  to receive the detent ball to prohibit rotation. Also, the locator pin  40  includes an enlarged annular portion  46  that fits within the adapter bore enlarged portion  31 . The locator pin  40  moves within the bore  30  of the adapter  28 . This enables the locator pin  40  to move in a first and second reciprocal direction. 
         [0020]    The clamping mechanism  50  is movably retained in the locator pin  40  by a stop  52 . The stop  52  is positioned at an end of the enlarged bore portion  44 . The stop  52  includes a slot  53  to receive the rod  54  of the clamping mechanism  50 . The stop  52  is secured to the enlarged annular portion  46  of the locator pin  40 . 
         [0021]    The clamping mechanism  50  includes a rod  54  and a finger  56 . The rod  54  has a cylindrical body  56  with annular flanges  58 ,  62 . Additionally, the rod  54  includes a head  60  that is substantially flat and planar. The rod annular flange  62  fits into the annular cut out of the piston rod extension  34  to couple the rod  54  with the piston rod extension  34 . The rod  54  is directly driven by the piston rod extension  34  which, in turn, is directly driven by the piston rod  20 . Thus, the rod  54  drives the locator pin  40  in its reciprocating pattern. 
         [0022]    The flat head  60  includes a projecting member or shelf  64  on one side of the head  60 . The projecting member or shelf  64  has a tapered surface slid inside the finger  56 . The projecting member or shelf  64  is the terminus of the head  60  and provides a top tapered surface. The projecting member or shelf  64  is the terminus of the head  60  and provides a top tapered surface. Also, a slot is shown in phantom so that the shelf spot can be reversed. 
         [0023]    The finger  56  has an overall rectangular box shape with a central slot  66 . The central slot  66  includes a side slot  68 . The side slot  68  has tapered surfaces to receive the tapered surfaces of the projecting member  64  of the head  60 . The central slot  66  receives the rod head  60 . A projection member is shown in phantom. Additionally, the finger  56  includes two minor sides  70  with an arcuate surface. The arcuate surface  70  enables the finger  56  to circumferentially align with the wall of the locator pin  40 . Thus, when the finger  56  is in a retracted position in the locator pin  40 , the aperture  45  in the locator pin  40  is closed. Thus, weld slag or the like is prohibited from entering into the locator pin. Thus, the minor sides  70  are substantially flush with the circumferential surface of the locator pin  40 . 
         [0024]      FIG. 7  illustrates the clamping mechanism  50 . The elements that are the same as previously discussed will be identified with the same reference numerals. The difference between the first embodiment lies in the rod head  60 ′ and the finger  56 ′. 
         [0025]    The rod head  60 ′ includes an angled slot  80  formed near the free end of the head  60 ′. The finger  56 ′ includes central slot  66 . A pin  82  extends from the sides to span the central slot  66 . The slot  80  and head  60 ′ engages the pin  82 . As the rod  54  reciprocates, the pin moves in the slot  80 . As the pin  82  moves in the slot  80 , the finger  56  reciprocates in the locator pin  40  from an extended and retracted position. Additionally, the pin could extend from the rod head  60 ′ and slots could be formed in the sides of the finger  56 ′. 
         [0026]    In operation, fluid enters into the actuator device moving piston  22  in a first direction. As this occurs, the clamping member  50  is driven. Since the locator pin  40  is dependent upon movement of the clamping member  50 , it also moves in the adapter  28 . The clamping member rod  54  moves in the bore  42  of the locator pin  40 . As this occurs, the tapered surface  64  of the projecting member slides on the tapered surface of slot  68  forcing the finger  56  outward through the aperture  45 . Thus, the finger  56  extends from the locator pin  40 . This continues until the flange  58  contacts the stop  52  at the terminus of the enlarged bore  44 . 
         [0027]    As the fluid continues to enter into the actuating device  14 , the piston rod  20  continues to move in the first direction. As this occurs, the extension  34  continues to draw the rod  54  in a first direction which, in turn, moves the locator pin  40 . Fluid continues to enter into the actuating device  14 . As this occurs, the locator pin  40  dependent upon the rod  54  movement, as well as the clamping device  50 , continues to move in the first direction until the clamping finger  56  contacts a workpiece  84  positioned on the surface  80  of the adapter  28 . Also, as the actuating device  12  reaches this position, the piston  24  locks in place, via the detent  26 . Thus, the clamping device  50  is locked in position on the workpiece. To release the clamping member  50 , fluid enters the cylinder  12  on a side of the piston  24 . The piston  24  moves in a second direction which reverses the direction of the piston rod  20  and extension  34 . This forces the rod  54  in the second direction which, in turn, retracts the finger  56  into the locating pin  40 . The rod  54  then drives the locator pin  40  into its position. 
         [0028]    The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.