Patent Publication Number: US-2012031217-A1

Title: Robotic arm

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is related to co-pending U.S. Patent Applications (Attorney Docket No. US34532 and US 34534), entitled “ROBOTIC ARM”, by Jin et al. These application have the same assignee as the present application and have been concurrently filed herewith. The above-identified applications are incorporated herein by reference. 
     BACKGROUND 
     1. Technical Field 
     This disclosure relates to robotic arms, particularly to robotic arms for handling freshly molded items 
     2. Description of Related Art 
     Molding machines typically use robotic arms to hold molded items. However, typical robotic arms have a complicated mechanism. 
     Therefore, there is a room for improved in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the exemplary robotic arm. Moreover, in the drawings like reference numerals designate corresponding parts throughout the several views. Wherever possible, the same reference numbers are used throughout the drawings to refer to the same or like elements of an embodiment. 
         FIG. 1  is an assembled view of an exemplary embodiment of a robotic arm. 
         FIG. 2  is another assembled view of the robotic arm shown in  FIG. 1 . 
         FIG. 3  is an exploded view of the robotic arm shown in  FIG. 1 . 
         FIG. 4  is an exploded view of the robotic arm shown in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-2 , an exemplary robotic arm  100  used in a molding machine (not shown) is disclosed. The robotic arm  100  can extend into the molding machine for holding and reto move molded items (not shown) in the molding machine. 
     The robotic arm  100  includes a mount  10 , a mounting board  20 , a lifting mechanism (not labeled), a first horizontal driving device  30 , a sliding mechanism  40 , a connecting board  50 , a second horizontal driving device  60  and a holder  70 . The lifting mechanism is mounted between the mount  10  and the first horizontal driving device  30 . The mounting board  20  is mounted to the first horizontal driving device  30 . The lifting mechanism is used to mechanically raise or lower the first horizontal driving device  30  relative to the mount  10  so the mounting board  20  can move in a first (e.g., vertical) direction A shown in  FIG. 1 . The first horizontal driving device  30  is mounted between the mount  10  and the mounting board  20  to move the mounting board  20  relative to the mount  10  in a second (first horizontal) direction B shown in  FIG. 1  perpendicular to the first direction A. The sliding mechanism  40  is mounted between the mounting board  20  and the connecting board  50  to control the connecting board  50  move relative to the mounting board  20  in a third (e.g., second horizontal) direction C shown in  FIG. 1  perpendicular to the first direction A and the second direction B. The second horizontal driving device  60  is mounted between the mounting board  20  and the connecting board  50  to enable the connecting board  50  to move relative to the mounting board  20  in the second direction B. The holder  70  is mounted to a distal end of the connecting board  50  and moves with the connecting board  50  relative to the mounting board  20 , for holding and reto move molded items in the molding machine. 
     Referring to  FIG. 2 , the lifting mechanism includes a guiding groove  13  and a pin  35  movably engaging with the guiding groove  13 . In this exemplary embodiment, the guiding groove  13  is defined in the mount  10  and the pin  35  is positioned on the first horizontal driving device  30 . When the first horizontal driving device  30  moves relative to the mount  10  in the first direction A, the pin  35  moves in the guiding groove  13 . 
     Referring to  FIGS. 1 and 3 , the first horizontal driving device  30  includes a cylinder  31 , an output rod  32  movably mounted on the cylinder  31  and a retaining board  33  mounted on a distal end of the output rod  32  for retaining the mounting board  20  to the first horizontal driving device  30 . The retaining board  33  defines a number of retaining holes  331  for mounting the mounting board  20  to the retaining board  33 . When the output rod  32  moves relative to the cylinder  31 , the retaining board  33  drives the mounting board  20  to move relative to the mount  10  and the first horizontal driving device  30  in the second direction B. 
     Referring to  FIGS. 3 and 4 , the mounting board  20  includes a main body  21  and a mounting arm  23  located near one side of the main body  21 . The mounting board  20  defines a number of mounting holes  213  in the main body  21 . Each mounting hole  213  corresponds to one of the retaining holes  331  for mounting the mounting board  20  to the retaining board  33 . The mounting board  20  further defines an opening  215  through the main body  21  for the second horizontal driving device  60  to pass through the mounting board  20 . 
     Referring to  FIGS. 1 and 3 , the sliding mechanism  40  is mounted between the mounting board  20  and the connecting board  50  to make the connecting board  50  move relative to the mounting board  20 . The sliding mechanism  40  includes a rail  41  and a sliding block  45 , the rail  41  movably engages with a sliding groove  451  defined in the sliding block  45 . In this exemplary embodiment, the rail  41  is positioned on the mounting arm  23  and the sliding block  45  is positioned on connecting board  50 , so the connecting board  50  can move relative to the mounting board  20  along the rail  41 . The sliding mechanism  40  further includes two stopping blocks  412  respectively positioned near opposite ends of the rail  41 . The stopping blocks  412  are used for preventing the sliding block  45  and the rail  41  from separating. 
     Referring to  FIGS. 1 and 3 , the second horizontal driving device  60  includes a seat  61  mounted to one side of the mounting board  20 , a gear  63  rotatably mounted on the seat  61  by a shaft  635 , a toothed rack  65  mounted to the connecting board  50 , a chassis  69  mounted to another side of the mounting board  20  and a motor  67  mounted to the chassis  69 . The motor  67  includes a driving pole  673  passing through the opening  215  to connect with the shaft  635 . The driving pole  673  drives the shaft  635  to rotate relative to the seat  61 . The gear  63  engages with the toothed rack  65 . Therefore, when the gear  63  rotates, the gear  63  drives the toothed rack  65  to move relative to the gear  63 . Additionally, the toothed rack  65  is mounted to the connecting board  50  so when the gear  63  rotates, the connecting board  50  can move together with the toothed rack  65 . 
     Referring to  FIGS. 2 and 4 , in assembly, the pin  35  is mounted in the guiding groove  13  to slidably mount the first horizontal driving device  30  to the mount  10 . The retaining holes  331  are respectively aligned with the mounting holes  213  and then a number of bolts  80  ( FIG. 1 ) are inserted in the retaining holes  331  and the mounting holes  213  to retain the mounting board  20  to the retaining board  33 . Referring to  FIGS. 1 and 2 , the seat  61  is mounted to the mounting board  20  with the shaft  635  aligned with the opening  215 , the chassis  69  is mounted to the mounting board  20  with the driving pole  673  passing through the opening  215  to connect with the shaft  635 . The rail  41  is mounted to mounting board  20  and the sliding block  45  is slidably mounted to the rail  41 . The holder  70  is retained to the connecting board  50 . The toothed rack  65  is retained to the connecting board  50 . The connecting board  50  is mounted to the sliding block  45  with the toothed rack  65  engaging with the gear  63 , to yield an assembled robotic arm  100 . 
     Referring to  FIG. 1 , in use, the first horizontal driving device  30  moves relative to the mount  10  by the lifting mechanism, to adjust the distance between the holder  70  and the molding machine in the first direction A. To adjust the distance between the holder  70  and the molding machine in the second direction B, the cylinder  31  is started to drive the mounting board  20  to move relative to the cylinder  31  until the holder  70  moves to a first predetermined position. To adjust the distance between the holder  70  and the molding machine in the third direction C, the motor  67  is started to drive the gear  63  to rotate so the toothed rack  65  moves until the holder  70  arrives in a second predetermined position. 
     It is to be understood that the sliding mechanism  40  and the connecting board  50  may be omitted, in this case, the holder  70  is directly mounted to the toothed rack  65 ; the toothed rack  65  is slidably and directly mounted to the mounting board  20 . Thus, the motor  67  drives the gear  63  to rotate so the toothed rack  65  moves relative to the mounting board  30  in the third direction C. It is also to be understood that the mounting board  20  can be directly and slidably mounted to the mount  10 , and the lifting mechanism can be omitted. 
     It is to be further understood that even though numerous characteristics and advantages of the exemplary embodiments have been set forth in the foregoing description, together with details of structures and functions of various embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the exemplary invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.