Abstract:
An apparatus for transporting objects may include a plurality of grippers having a first spacing at a first position and second spacing at a second position. A drive mechanism may be provided is for selectively displacing the grippers from the first position to the second position to adjust the spacing between the grippers.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates, in general, to an apparatus for gripping an article, for example, while transporting the article. More specifically, the apparatus can be suitable for gripping a flat portion of the article, for example, the seam of a foil bag. The apparatus can be used to suspend the article, for example, while conveying the article horizontally. 
         [0002]    Gripping apparatuses can include two clamping jaws movable relative to each other, wherein the jaws are movable via a transmission element, from a gripping position to an opened position and vice versa. The gripping apparatuses available in the market, however, are often not suitable or are limited when suspending and transporting thin articles, such as foil bags. For example, the clamping force of the jaws applied on the articles may be compromised by irregularities in the transmission elements. Whereas the compromised force may be insignificant when the article is relatively thick, thin articles such as foil bags may be sensitive to such compromises in the clamping force. 
         [0003]    In light of the shortcomings described above, it is desirable to provide an apparatus and system for gripping and transporting products. 
       SUMMARY 
       [0004]    Generally speaking, the present invention is directed toward an apparatus for gripping an article for transport, preferably a relatively thin article, such as a foil bag having a relatively thin seam. The gripping apparatus can contact both sides of the seam and apply sufficient pressure, or clamping force, to grasp and suspend the article as it is being transported to another station, conveyor belt, etc. The gripping apparatus preferably includes a toggle lever for controlling the clamping motion of the gripping apparatus. 
         [0005]    Objects and features of the present invention will become apparent from the following detailed description, considered in conjunction with the accompanying drawing figure. It is to be understood, however, that the drawings are designed solely for the purpose of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES  
         [0006]    For a fuller understanding of the invention, reference is had to the following description, taken in connection with the accompanying drawings, in which: 
           [0007]      FIG. 1  is a perspective view of an apparatus in accordance with an embodiment of the invention in a first position; 
           [0008]      FIG. 2  is a cross-sectional view of the apparatus of  FIG. 1 ; 
           [0009]      FIG. 3  is a cross-sectional view of the apparatus of  FIG. 1  in a second position. 
       
    
    
     DETAILED DESCRIPTION  
       [0010]    Reference is made to  FIGS. 1-3 , wherein an embodiment of a gripping apparatus  1  is illustrated.  FIG. 1  shows gripping apparatus  1  gripping an article  2 , such as a foil bag. Article  2  can include a sealing edge  3 , which can be thin, preferably having a thickness of less than about 0.5 mm, more preferably between about 0.02 and 0.5 mm. 
         [0011]    An exemplary embodiment of gripping apparatus  1  can be connected to and, preferably extends downward from, a continuously rotating conveying system, such as a conveyor chain. Alternatively, gripping apparatus  1  can be mounted on individually movable arms, or moved back and forth, or otherwise arranged to convey article  2  from one position to another. 
         [0012]    Referring to  FIGS. 1-3 , gripping apparatus  1  can include a clamping assembly having a first jaw  4   a  and a second jaw  4   b  pivotally displaceable with respect to each other. The clamping assembly can also include a first arm  13   a  connected to first jaw  4   a,  and a second arm  13   b  connected to second clamping jaw  4   b.  Preferably, jaws  4   a,    4   b  are shaped to accommodate article  2  being gripped therebetween. For example, in the embodiment shown, jaws  4   a,    4   b  are substantially rectangular having a flat inner surface to grip the flat sealing edge  3  of article  2 . 
         [0013]    Gripping apparatus  1  preferably includes an actuating assembly  9  constructed and arranged to displace jaws  4   a,    4   b  toward and away from each other. An exemplary embodiment of actuating assembly  9  illustrated in  FIGS. 1-3  includes a base  15 , a rod  18 , an intermediate member  11 , and a toggle lever comprising a first lever  8   a  and a second lever  8   b.  Preferably, first lever  8   a  is connected to intermediate member  11  at a first end and first arm  13   a  at a second end. Likewise, second lever  8   b  is connected to intermediate member  11  at a first end and second arm  13   b  at a second end. The embodiment of levers  8   a,    8   b  as shown have a generally elongated cylindrical shape. Therefore, reference is made to first and second ends of levers  8   a,    8   b.  However, it is to be understood that levers  8   a,    8   b  can include a variety of shapes and are not limited to elongated members or cylindrical members. 
         [0014]    Referring to the embodiment of the toggle lever illustrated, first lever  8   a  is pivotally attached to intermediate member  11  via a first pivot  10   a,  and second lever  8   b  is pivotally attached to intermediate member  11  via a first pivot  10   b.  Additionally, first lever  8   a  can be pivotally attached to first arm  13   a  via a third pivot  12   a,  and second lever  8   b  can be pivotally attached to second arm  13   b  via a fourth pivot  12   b.  Preferably, first pivot  10   a  and second pivot  10   b  are spaced apart from third pivot  12   a  and fourth pivot  12   b,  respectively. 
         [0015]    First arm  13   a  is preferably fixedly connected to first jaw  4   a,  and second arm  13   b  is preferably fixedly connected to second jaw  4   b.  The toggle lever in accordance with the invention preferably provides an increased force generated by jaws  4   a,    4   b  with reduced movement and less force than systems known in the art. Therefore, the gripper apparatus in accordance with an embodiment of the invention can be used at higher speeds and lower pressure than previously known systems. 
         [0016]    Gripper apparatus can further include a base  15  having an aperture  17  through which rod  18  extends in a direction represented as double arrow P. Preferably, the wear and tear of rod  18  and aperture  17  is insignificant. Preferably, rod  18  is displaceable along aperture  17  toward and away from jaws  4   a,    4   b.  Such linear motion preferably reduces certain drawbacks of previously known systems. Base  15  can also be connected to the clamping assembly, preferably to first and second arms  13   a,    13   b.  In the embodiment shown, first and second arms  13   a,    13   b  are pivotally connected to base  15  via fifth pivot  14   a  and sixth pivot  14   b,  respectively. In accordance with the embodiment shown, fifth pivot  14   a  and sixth pivot  14   b  are spaced away from third pivot  12   a  and fourth pivot  12   b,  respectively. Preferably, portions of base  15  extend toward arms  13   a,    13   b  as shown in  FIGS. 1-3 . 
         [0017]    Referring to  FIG. 2 , rod  18  can be connected to an operating head  20 , which can include, by way of non-limiting example, a cam follower of a cam control for levers  8   a,    8   b.    
         [0018]    Alternatively, operating head  20  can be selectively depressed or otherwise displaced toward jaws  4   a,    4   b,  to displace rod  18  toward jaws  4   a,    4   b.  Preferably, rod  18  is fixed to operating head  30  so that the movement of operating head  20  is transferred into the movement of rod  18 . 
         [0019]    A spring  21  is preferably provided to urge operating head  20  away from base  15 , thus urging rod  18  away from jaws  4   a,    4   b.  Referring to  FIG. 3 , spring  21  preferably has a minimum height wherein spring  21  is substantially completely contracted between base  15  and operating head  20 . More specifically, when spring  21  abuts stopper surface  23  of operating head  20  and can no longer contract, for example, based on the thickness of spring  21 , rod  18  is preferably fully extended. 
         [0020]    When rod  18  is fully extended in accordance with the embodiment shown in  FIG. 3 , intermediate member  11  is moved toward jaws  4   a,    4   b.  Because levers  8   a,    8   b  of the embodiment shown are pivotally attached at one end to intermediate member  11  and arms  13   a,    13   b  at the opposite end, as intermediate member  11  is moved away from base  15  toward jaws  4   a,    4   b,  levers  8   a,    8   b  are pivoted about first and second pivots  10   a,    10   b  toward base  15  and away from jaws  4   a,    4   b  to create an angle of less than 180° with respect to one another. Additionally, because arms  4   a,    4   b  are pivotally connected to base  15  at fifth and sixth pivots  14   a,    14   b,  the pivoting motion of levers  8   a,    8   b  causes arms  13   a,    13   b  to pivot about fifth and sixth pivots  14   a,    14   b  away from each other. According, jaws  14   a,    14   b,  which are fixed to arms  13   a,    13   b,  are also separated and move apart from one another, thus creating a gap in which article  2  can be received. 
         [0021]    Reference is made to  FIG. 2 , wherein an embodiment of rod  18  is fully retracted, which is preferably the rest position of gripping apparatus  1  when no force is exerted thereon. In the embodiment shown, first pivot  10   a,  second pivot  10   b,  third pivot  12   a  and fourth pivot  12   b  are aligned in a common plane. As shown, intermediate member  11  is moved toward base  15  until prevented from moving further. For example, intermediate member  11  preferably has a width that is greater than the diameter of aperture  17 , and therefore a face  19  of intermediate member  11  can abut a guide portion  16  of base  15 , whereupon rod  18  is prevented from retracting any further. As shown, levers  8   a,    8   b  can pivot about first and second pivots  10   a,    10   b  away from base  15  and toward jaws  4   a,    4   b  until levers  8   a,    8   b  are aligned, more specifically, having an angle of 180° with respect to one another. Levers  8   a,    8   b  pivot about third and fourth pivots  12   a,    12   b  with respect to arms  13   a,    13   b.  Preferably, simultaneously, arms  13   a,    13   b  pivot about fifth and sixth pivots  14   a,    14   b  toward each other until jaws  4   a,    4   b  contact each other. Accordingly, if a portion of article  2  is present between jaws  14   a,    14   b,  jaws  4   a,    4   b  can grasp the portion of article  2  therebetween. Preferably, the opposing force between jaws  4   a,    4   b  is sufficient to maintain a relatively thin article  2 , such as a foil bag, more specifically, the sealing edge  3  in place. The force is preferably strong enough to suspend and convey article  2  while grasping sealing edge  3 . 
         [0022]    In accordance with an exemplary embodiment, a lining  6  is provided on the surface of jaws  4   a,    4   b  to facilitate grasping and retaining article  2  between jaws  4   a,    4   b.  Lining  6  is preferably a friction-increasing lining. Examples of lining  6  include a nap lining having relatively low flexibility. 
         [0023]    Preferably, gripping apparatus  1  is substantially symmetrical about a center plane  1 ′ extending through operating head  20 , rod  18 , intermediate member  11  and between jaws  4   a,    4   b.  For example, levers  8   a,    8   b  are symmetrical to each other about center plane  1 ′. 
         [0024]    The examples provided are merely exemplary, as a matter of application specific to design choice, and should not be construed to limit the scope of the invention in any way. 
         [0025]    Thus, while there have been shown and described and pointed out novel features of the present invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit of the invention. For example, two or more elements can be combined into single elements, and single elements can be divided into multiple parts without deviating from the scope of the invention. Additionally, other alterations can be made as a matter of application specific to design choice, without deviating from the scope of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. 
         [0026]    It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.