Patent Publication Number: US-2012032383-A1

Title: Clamp apparatus

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure generally relates to a clamp apparatus. 
     2. Description of Related Art 
     A commonly used clamp apparatus used with a manipulator includes a first clamp arm, a second clamp arm opposite to and movable relative to the first clamp arm, and a linear actuator. Opposite ends of the first and second clamp arms define a plurality of contact surfaces corresponding to the shape and size of a clamped workpiece, respectively. Generally, the linear actuator is a cylinder moving the second clamp arm toward and away from the first clamp arm along a predetermined straight line. However, since the translation movement of the first and second clamp arms is along the straight line, the clamp apparatus has a larger dimension in this direction, thus requiring even more space for the clamping operation. 
     Therefore, there is room for improvement within the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is an assembled, isometric view of one embodiment of a clamp apparatus, in a disengaged state. 
         FIG. 2  is a plan view of the clamp apparatus of  FIG. 1 . 
         FIG. 3  is an exploded, isometric view of the clamp apparatus of  FIG. 1 . 
         FIG. 4  is an isometric view of one embodiment of the clamp apparatus, in an engaged state. 
         FIG. 5  is a plan view of the clamp apparatus of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 through 3 , one embodiment of a clamp apparatus  100  includes a mounting base  20 , a rotation actuator  30  mounted to the mounting base  20 , a beveled active gear  40  driven by the rotation actuator  30 , and a plurality of clamp jaws  50  arranged around the mounting base  20  and rotated by the beveled active gear  40 . 
     Each clamp jaw  50  includes a beveled driven gear  51  engaging the beveled active gear  40  of the clamp apparatus  100 , and a clamp body  52  connected to the beveled driven gear  51 . When the clamp jaws  50  are rotated by the beveled active gear  40 , the clamp bodies  52  engage and cooperatively clamp a workpiece. 
     In the illustrated embodiment, the clamp apparatus  100  includes three clamp jaws  50  evenly distributed around a circumference thereof. The beveled active gear  40  rotates about a first rotation axis A, and the three beveled driven gears  51  are rotated about three second rotation axes B 1 , B 2 , B 3 , respectively. The second rotation axes B 1 , B 2 , B 3  are arranged in the same plane and intersect with each other to form a 120° angle therebetween (between each pair of adjacent second rotation axes, i.e. between B 1  and B 2 , for example). The beveled active gear  40  is rotated or driven by the rotation actuator  30 , whereby the beveled driven gear  51  is also rotated, and the clamp bodies  52  rotate toward or away from each other, to clamp or release a workpiece. 
     The mounting base  20  is substantially cylindrical and includes a top surface  21  and a sidewall  22  extending from the edge of the top surface  21 . The top surface  21  and the sidewall  22  cooperatively define a receiving chamber  23 . The top surface  21  defines a plurality of first mounting holes  212  and a plurality of second mounting holes  213 . The first mounting holes  212  are adapted to mount the mounting base  20  to a manipulator, and the second mounting holes  213  are adapted to mount the mounting base  20  to the rotation actuator  30  so as to receive the rotation actuator  30  in the receiving chamber  23 . In the illustrated embodiment, the centers of the first mounting holes  212  are arranged in a first circle and the centers of the second mounting holes  213  are arranged in a second circle having a diameter less than that of the first circle. 
     The rotation actuator  30  has an output shaft  31  on which the beveled active gear  40  is mounted. The rotation actuator  30  may be a stepping motor or a server motor. The rotation actuator  30  can be connected to a controller and thereby be activated. 
     Each clamp jaw  50  further includes a sliding sleeve  53 , a connecting member  54  slidably retained in the sliding sleeve  53 , a connecting shaft  55  fixed to the sliding sleeve  53  and the beveled driven gear  51 , and a plurality of bob-weights  56  positioned on a distal end of the connecting member  54 . The clamp body  52  is fixed to an end of the connecting member  54 . 
     The sliding sleeve  53  defines a through hole  531  for the connecting member  54 . The connecting member  54  is slidable relative to the sliding sleeve  53  and can be retained in a plurality of positions by a fixing means (not shown), so that the distance between the rotation axis of the connecting shaft  55  and the clamp body  52  is adjustable to accommodate the sizes and shapes of various workpieces. 
     The connecting member  54  includes a first end  541  and a second end  542  at the opposite end. The first end  541  defines a plurality of fixing holes  5412  to be detachably connected to the clamp body  52 . The bob-weight  56  is secured on the second end  542 . The dynamic balance of the jaws  50  can be adjusted by increasing or reducing the total amount of the weight of the bob-weights  56 . 
     The clamp body  52  is substantially L-shaped and includes a connecting portion  521  and a contact portion  522  extending from the connecting portion  521 . The connecting portion  521  defines a first connecting hole  5211  on an end surface, and a plurality of second connecting holes  5212  on a side surface of the connecting portion  521  communicated with the first connecting hole  5211 . The first end  541  of the connecting member  54  is received in the first connecting hole  5211  and retained by a fastener (not shown) engageably received in the second connecting hole  5212  and the corresponding fixing hole  5412 . Thus, the clamp bodies  52  are adjustable according to the shape and size of the workpieces, thus increasing the usage flexibility of the clamp apparatus  100 . It should be understood that the clamp bodies  52  can be detachably connected to the connecting member  54  by any other means. 
     In the illustrated embodiment, the contact portion  522  has only one contact surface  5221  formed on one side thereof. In other embodiments, the contact portion  522  can be provided with two opposite contact surfaces (not shown) formed on opposite sides thereof, thus the clockwise and counterclockwise rotations of the clamp jaws  50  can be provided to accommodate for different workpieces. 
     The clamp apparatus  100  further includes a support member  60  positioned between the rotation actuator  30  and the beveled active gear  40 . The support member  60  is disc-shaped and defines an axial through hole  61  for the output shaft  31  of the rotation actuator  30 , a plurality of mounting holes  62  formed around the through hole  61  for fixing the support member  60  to the mounting base  20 , and a plurality of radial shaft holes  63  for the plurality of connecting shafts  55 . 
     The mounting base  20  forms a plurality of stopper portions  221  extending from the bottom of the sidewall  22 . Each stopper portion  221  defines a cutout  2212 . The stopper portion  221  is positioned between the beveled driven gear  51  and the connecting member  54 , and the connecting shaft  55  is rotatably received in the cutout  2212  and engaged in the shaft hole  63 , thereby rotatably connecting the clamp jaws  50  and the support member  60 . 
     It should be understood that in alternative embodiments, the support member  60  can be omitted, wherein the mounting base  20  defines a fixing hole, the connecting shaft  55  defines a fixing groove on an end, and a clip can be engaged in the fixing groove to rotatably connect the clamp jaws  50  and the support member  60 . 
     The operation of the clamp apparatus  100  is as follows.  FIGS. 1 and 2  show the clamp apparatus  100  in a disengaged state, and  FIGS. 4 and 5  show the clamp apparatus  100  in an engaged state. In use, the rotation actuator  30  is activated to rotate the beveled active gear  40 , and the clamp jaws  50  are rotated via the engagement of the beveled active gear  40  and the beveled driven gears  51 , such that the clamp bodies  52  are moved toward or away from each other, thereby switching between the engaged and disengaged states. Accordingly, when the three clamp jaws  50  are rotated about the second rotation axes B 1 , B 2 , B 3  respectively, in either direction, the clamp apparatus  100  clamps and releases the workpiece, respectively. Since the clamp jaws  50  are arranged around the mounting base  20  and rotated about the second rotation axes B 1 , B 2 , B 3  perpendicular to the first rotation axis A of the beveled active gear  40 , the clamp apparatus  100  presents a more compact size. 
     It should be understood that in other embodiments, the first rotation axis A can be angled to the second rotation axes B 1 , B 2 , B 3 . 
     It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages.