Abstract:
A method for reloading workpieces includes providing a manipulator having a connecting base and a plurality of grasping assemblies arranged on the connecting base, providing a plurality of original workpieces and a plurality of machined workpieces positioned in a plurality of machining positions, grasping the original workpieces by at least one grasping assembly, with at least one grasping assembly vacant, grasping one machined workpiece by one vacant grasping assembly, rotating the connecting base, so that one original workpiece is placed in one machining position by one grasping assembly, further rotating the connecting base until another vacant grasping assembly is opposite to another machining position, and repeating grasping the machined workpieces from the machining positions and placing the original workpieces on the machining positions until a last original workpiece is placed on one machining position. The manipulator used in the present method for reloading workpieces is also provided.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates generally to methods for reloading workpieces and, more particularly, to a method for reloading workpieces using a manipulator. 
     2. Description of Related Art 
     Industrial robotic machines are widely used in the manufacturing industry to achieve high efficiency. A manipulator generally has a claw for holding a workpiece in a machining process. 
     A typical industrial robotic machine includes a first manipulator and a second manipulator, each manipulator including a main body and a plurality of claws assembled at an end of the main body. The first manipulator grasps a plurality of first workpieces, and places the first workpieces on a plurality of machining positions of a machine center. When the first workpieces are machined by the machining center, the second manipulator grasps a plurality of second workpieces. After the first workpieces are machined to desired products, the first manipulator grasps the products and transports the products away from the machining center. The second manipulator places the second workpieces on the machining positions of the machine tool for machining. 
     The method of using two manipulators to reduce waiting time for the machine tool increases machining cost of the products because of the use of two manipulators. 
     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 isometric view of a first embodiment of a manipulator. 
         FIG. 2  is a flowchart of one embodiment of a method for reloading workpieces using the manipulator of  FIG. 1 . 
         FIGS. 3 to 9  show a process of reloading workpieces using the manipulator of  FIG. 1 . 
         FIG. 10  is a flowchart of another embodiment of a method for reloading workpieces using the manipulator of  FIG. 1 . 
         FIG. 11  is an isometric view of a second embodiment of a manipulator. 
         FIG. 12  is a flowchart of one embodiment of a method for reloading workpieces using the manipulator of  FIG. 11 . 
         FIG. 13  is a flowchart of another embodiment of a method for reloading workpieces using the manipulator of  FIG. 11 . 
         FIG. 14  is an isometric view of a third embodiment of a manipulator. 
         FIG. 15  is a flowchart of one embodiment of a method for reloading workpieces using the manipulator of  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a first embodiment of a manipulator  10  includes a support arm  11 , a connecting base  13 , a first grasping assembly  15 , a second grasping assembly  16 , a third grasping assembly  17 , and a fourth grasping assembly  18 . Each of the first grasping assembly  15 , the second grasping assembly  16 , the third grasping assembly  17 , and the fourth grasping assembly  18  includes a plurality of substantially parallel grasping poles  101 . 
     The support arm  11  may be a cylindrical pole. An end of the support arm  11  is connected to a driving device (not shown), such as a motor, and the other end of the support arm  11  is connected to the connecting base  13 . The support arm  11  and the connecting base  13  are rotated by the driving device. 
     The connecting base  13  may be substantially cubic. In the illustrated embodiment, the connecting base  13  includes a plurality of curved surfaces  130 , a first side surface  133 , a second side surface  135 , a third side surface  137 , and a fourth side surface  139 . The first side surface  133 , the second side surface  135 , the third side surface  137 , and the fourth side surface  139  connect in turn via the curved surfaces  130 , and are substantially perpendicular to each other. 
     The first grasping assembly  15  is substantially perpendicularly positioned on the first side surface  133 . The second grasping assembly  16  is substantially perpendicularly positioned on the second side surface  135 . The third grasping assembly  17  is substantially perpendicularly positioned on the third side surface  137 . The fourth grasping assembly  18  is substantially perpendicularly positioned on the fourth side surface  139 . That is, the first grasping assembly  15  is substantially perpendicular to the second grasping assembly  16 , the second grasping assembly  16  is substantially perpendicular to the third grasping assembly  17 , the third grasping assembly  17  is substantially perpendicular to the fourth grasping assembly  18 , and the fourth grasping assembly  18  is substantially perpendicular to the first grasping assembly  15 . 
     A method for reloading a plurality of workpieces using the manipulator  10 , according to  FIG. 2 , is provided. 
     Referring also to  FIG. 3 , in a step SI  00 , the manipulator  10 , a plurality of original workpieces  60 , and a plurality of machined workpieces  70  are provided. The machined workpieces are placed on a plurality of machining positions  81  of a machining center  80 . 
     In a step S 200 , the manipulator  10  is rotated such that first grasping assembly  15  corresponds to a first of the plurality of original workpieces  60 . The first grasping assembly of the manipulator  10  grasps the first of the plurality of original workpieces  60  via the grasping poles  101 . The manipulator  10  rotates 90° in a direction A, and the second grasping assembly  16  corresponds to a second of the plurality of original workpieces  60 . The second grasping assembly  16  grasps the second of the plurality of original workpieces  60  via the grasping poles  101 . The manipulator  10  further rotates 90° in the direction A, and the third grasping assembly  17  corresponds to a third of the plurality of original workpieces  60 . The third grasping assembly  17  grasps the third of the plurality of original workpieces  60  via the grasping poles  101 . The manipulator  10  rotates 90° in the direction A, and moves to a first of the plurality of machining positions  81  of the machining center  80 , therefore, the fourth grasping assembly  18  faces the first of the plurality of machining positions  81  (as shown in  FIG. 4 ). 
     In a step S 300 , the fourth grasping assembly  18  grasps one machined workpiece  70 , on the first of the plurality of machining positions  81  (as shown in  FIG. 5 ). The manipulator  10  further rotates 90° in the direction A, and places the first original workpiece on the first of the plurality of machining positions  81  via the first grasping assembly  15  (as shown in  FIG. 6 ). The manipulator  10  moves to a second of the plurality of machining positions  81 , and the first grasping assembly  15  grasps a machined workpiece on the second of the plurality of machining positions  81  (as shown in  FIG. 7 ). The manipulator  10  further rotates 90° in the direction A, and places the second original workpiece on the second of the plurality of machining positions  81  via the second grasping assembly  16  (as shown in  FIG. 8 ). The manipulator  10  moves to a third of the plurality of machining positions  81 , and the second grasping assembly  16  grasps a machined workpiece on the third of the plurality of machining positions  81 . The manipulator  10  further rotates 90° in direction A, and places the third original workpiece on the third of the plurality of machining positions  81  via the third grasping assembly  17  (as shown in  FIG. 9 ). 
     The manipulator  10  moves away from the machining center  80 . The machined workpieces  70  on the first grasping assembly  15 , the second grasping assembly  16 , and the third grasping assembly  17  are unloaded from the manipulator  10 . The manipulator  10  then reloads a plurality of original workpieces  60  at one time. 
     Another embodiment of a method for reloading a plurality of workpieces using the manipulator  10 , according to  FIG. 10 , is also provided. 
     In a step S 400 , the manipulator  10 , a plurality of original workpieces  60 , and a plurality of machined workpieces  70  are provided. The machined workpieces are placed on a plurality of machining positions  81  of a machining center  80 . 
     In the step S 500 , each of the first grasping assembly  15  and the second grasping assembly  16  grasps an original workpiece  60 . The manipulator  10  moves to the first plurality of machining positions  81  of the machining center  80  with the third grasping assembly  17  opposite to the first plurality of machining positions  81 . The third grasping assembly  17  grasps a machined workpiece  70  in the first of the plurality of machining positions  81 . 
     In the step S 600 , the manipulator  10  rotates 180° in the direction A, and the first grasping assembly  15  places the original workpiece  60  in the first of the plurality of machining positions. The manipulator  10  rotates 90° opposite to direction A, and moves to a second of the plurality of machining positions  81 . The fourth grasping assembly  18  grasps a machined workpiece  70  on the second of the plurality of machining positions  81 . The manipulator  10  further rotates 180° in the direction A, and the second grasping assembly  16  places the original workpiece  60  on the second of the plurality of machining positions  81 . The manipulator  10  moves away from the machining center  80 . The machined workpieces on the third grasping assembly  17  and fourth grasping assembly  18  are unloaded from the manipulator  10 . 
     In the methods disclosed, before moving to the machining center  80  to reload workpieces  60 , one or more grasping assemblies of the manipulator  10  are vacant and the rest grasp original workpieces  60 . Therefore, the manipulator  10  can unload the machined workpieces  70  on the machining center  80  and load the original workpieces  60  on the machining center  80  at one time, increasing the efficiency of the manipulator  10 . 
     Referring to  FIG. 11 , a second embodiment of a manipulator  20  includes a support arm  21 , a connecting base  23 , a first grasping assembly  24 , a second grasping assembly  25 , a third grasping assembly  26 , a fourth grasping assembly  27 , a fifth grasping assembly  28 , and a sixth grasping assembly  29 . Each of the first grasping assembly  24 , the second grasping assembly  25 , the third grasping assembly  26 , the fourth grasping assembly  27 , the fifth grasping assembly  27 , and the sixth grasping assembly  27  includes a plurality of substantially parallel grasping poles  201 . 
     The support arm  21  may be a cylindrical pole. An end of the support arm  21  is connected to the driving device, and the other end of the support arm  21  is connected to the connecting base  23 . The support arm  21  and connecting base  23  are rotated by the driving device. 
     The connecting base  23  may be substantially cylindrical or hexagonal. The connecting base  23  includes a first side surface  233 , a second side surface  234 , a third side surface  235 , a fourth side surface  236 , a fifth side surface  237  and a sixth side surface  238 . The first side surface  233 , the second side surface  234 , the third side surface  235 , the fourth side surface  236 , the fifth side surface  237  and the sixth side surface  238  connect in turn via curved surfaces  230 . An angle between two adjacent grasping assemblies is about 60°. 
     A method for reloading a plurality of workpieces using the manipulator  20 , according to  FIG. 12 , is provided. 
     In the step S 700 , the manipulator  20 , a plurality of original workpieces  60 , and a plurality of machined workpieces  70  are provided. The machined workpieces are placed on a plurality of machining positions  81  of the machining center  80 . 
     In the step S 800 , the manipulator  20  rotates 60° continuously in a direction B as shown in  FIG. 12  until the first grasping assembly  24 , a second grasping assembly  25 , a third grasping assembly  26 , a fourth grasping assembly  27 , and a fifth grasping assembly  28  grasp an original workpiece  60  via the grasping poles  201 . The sixth grasping assembly  29  is vacant. 
     In the step S 900 , when a plurality of original workpieces  60  has been machined to a plurality of machined workpieces  70  on the machine center  80 , the manipulator  20  moves to a first of the plurality of machining positions  81  of the machining center  80  with the sixth grasping assembly  29  opposite to the first of the plurality of machining positions  81 . The sixth grasping assembly  29  grasps a machined workpiece  70  on the first of the plurality of machining positions  81 . The manipulator  20  further rotates 60° in the direction B, and places the original workpiece  60  grasped by the first grasping assembly  24  on the first of the plurality of machining positions  81 . 
     This is repeated until the original workpieces  60  grasped by the second grasping assembly  25 , the third grasping assembly  26 , the fourth grasping assembly  27 , and the fifth grasping assembly  28  are placed on the machining positions  81  and the machined workpieces  70  are grasped by the first grasping assembly  24 , the second grasping assembly  25 , the third grasping assembly  26 , and the fourth grasping assembly  27 . The manipulator  20  moves away from the machine center  80 , and five machined workpieces  70  are unloaded from the manipulator  10 . 
     Another method for reloading a plurality of workpieces  60  using the manipulator  20 , according to  FIG. 13 , is also provided. 
     In the step S 1000 , the manipulator  20 , a plurality of original workpieces  60 , and a plurality of machined workpieces  70  are provided. The machined workpieces are placed on a plurality of machining positions  81  of the machining center  80 . 
     In the step S 1100 , each of the first grasping assembly  24 , the second grasping assembly  25 , and the third grasping assembly  26  grasps an original workpiece  60 . The manipulator  10  moves to the first machining position  81  of the machining center  80  with the fourth grasping assembly  27  opposite to the first machining position  81 . 
     In the step S 1200 , the fourth grasping assembly  27  grasps a machined workpiece  70  in the first of the plurality of machining positions  81 . The manipulator  10  rotates 180° in direction B, and the first grasping assembly  24  places the original workpiece  60  in the first of the plurality of machining positions  81 . The manipulator  10  rotates 120° opposite the direction B, and moves to the second of the plurality of machining positions  81 . The fifth grasping assembly  28  grasps a machined workpiece  70  in the second of the plurality of machining positions  81 . The manipulator  20  further moves and rotates as described, until two original workpieces  60  grasped by the second grasping assembly  25  and the third grasping assembly  26  are placed in the machining positions  81 , and two machined workpieces  70  are grasped by the fifth grasping assembly  28  and the sixth grasping assembly  29 . The manipulator  20  moves away from the machine center  80 , and three machined workpieces  70  are unloaded from the manipulator  20 . 
     Referring to  FIG. 14 , a third embodiment of a manipulator  30  includes a support arm  31 , a connecting base  33 , a first grasping assembly  35 , and a second grasping assembly  37  opposite to the first grasping assembly  35 . Each of the first grasping assembly  35  and the second grasping assembly  37  includes a plurality of substantially parallel grasping poles  301 . 
     The support arm  31  may be a cylindrical pole. An end of the support arm  31  is connected to the driving device, and the other end of the support arm  31  is connected to the connecting base  33 . The support arm  31  and connecting base  33  are rotated by the driving device. 
     The connecting base  33  is substantially cubic. The connecting base  33  includes a first side surface  333  and a second side surface  335  opposite to the first side surface  333 . The first grasping assembly  35  is substantially perpendicularly positioned on the first side surface  333 . The second grasping assembly  37  is substantially perpendicularly positioned on the second side surface  337 . The first grasping assembly  35  is aligned with the second grasping assembly  37 . That is, an angle between the first grasping assembly  35  and the second grasping assembly  37  is about 180°. 
     One embodiment of a method for reloading a plurality of workpieces  60  using the manipulator  30 , according to  FIG. 15 , is provided. 
     In the step S 1300 , the manipulator  30 , a plurality of original workpieces, and a plurality of machined workpieces are provided. The machined workpieces are placed on a plurality of machining positions of the machining center. 
     In the step S 1400 , the first grasping assembly  35  grasps an original workpiece  60  via the grasping poles  301 . The manipulator  30  rotates 180° in a direction C as shown in  FIG. 15 , and moves to a machining position  81  of the machine center  80  with the second grasping assembly  37  opposite to the machining position  81 . 
     In the step S 1500 , the second grasping assembly  37  grasps a machined workpiece  70  on the machining position  81  via the grasping poles  301 . The manipulator  30  further rotates 180° in the direction C, and the first grasping assembly  35  places the original workpiece  60  on the machining position  81 . The manipulator  30  moves away from the machine center  80 , and the machined workpiece  70  is unloaded from the manipulator  30 . 
     It should be pointed out that the manipulator may include eight or more grasping assemblies, with the angle between every two adjacent grasping assemblies remaining the same. Each grasping assembly may include one or more grasping poles according to the size of the workpiece. The connecting base may be other shapes, such as a sphere. 
     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.