Vacuum-gripper

Abstract

The present invention relates to a vacuum gripper and in particular to a vacuum gripper for gently gripping work-pieces having sensitive surfaces, such as solar cells, wafers, or panels for flat screens, and for gripping heavy glass plates or plates made of other material having a very smooth surface that are stacked on top of each other and should be removed from above, wherein the vacuum gripper has the following characteristics: a straight or curved gripper plate ( 2 ), at least one suction opening ( 3; 3 a ), which is provided in the gripper plate ( 2 ), wherein a workpiece throttle surface ( 6 ) is formed around the suction opening ( 3 ), at least one recess ( 4 ), which is provided in the side of the gripper plate ( 2 ) facing the workpiece, outside of the workpiece throttle surface ( 6 ) relative to the suction opening ( 3 ), and at least one ventilation hole ( 5 ), which is provided within each recess ( 4 ).

1 . Vacuum gripper for gripping a work-piece ( 1 ), the vacuum gripper comprising the following features:
 a plan or curved gripper plate ( 2 ),   at least one suction port ( 3 ;  3   a ) which the gripper plate ( 2 ) is provided with, wherein a work-piece suction throttling zone ( 6 ) is formed around the suction port ( 3 ),   at least one recess ( 4 ) provided in the gripper plate ( 2 ) at that side thereof directed the work-piece and arranged beyond the work-piece suction throttling zone ( 6 ) formed around the suction port ( 3 ), and   at least one vent hole ( 5 ) formed within each of the recesses ( 4 ).   
     
     
         2 . Vacuum gripper according to  claim 1 , characterized in that the cross sections of the vent holes ( 5 ) are variable.  25   
     
     
         3 . Vacuum gripper according to  claim 1 , characterized in that several vent holes ( 5 ) are formed within each of the recesses, which can be closed selectively. 
     
     
         4 . Vacuum gripper according to  claim 1 , characterized in that the vent holes ( 5 ) are filled with a porous material. 
     
     
         5 . Vacuum gripper according to  claim 4 , characterized in that the porous material is a foamed plastic having open pores and shaped into a plug. 
     
     
         6 . Vacuum gripper according to  claim 1 , characterized in that the vent holes ( 5 ) comprise exchangeable air filters. 
     
     
         7 . Vacuum gripper according to  claim 1 , characterized in that the vent holes ( 5 ) are tap-holes for screwing in nozzles having different geometries. 
     
     
         8 . Vacuum gripper according to  claim 1 , characterized in that the vent holes ( 5 ) comprise controllable flow valves. 
     
     
         9 . Vacuum gripper according to  claim 1 , characterized in that the volumes of the recesses ( 4 ) are variable. 
     
     
         10 . Vacuum gripper according to  claim 1 , characterized in that several work-piece suction throttling zones ( 6 ) are provided within a gripper plate ( 2 ). 
     
     
         11 . Vacuum gripper according to  claim 1 , characterized in that the gripper plate ( 2 ) is formed as air bearing having air exit nozzles. 
     
     
         12 . Vacuum gripper according to  claim 1 , characterized in that the gripper plate ( 2 ) is mechanically coupled to at least one ultrasonic vibrator, wherein the gripper plate ( 2 ) is dimensioned so that it forms an ultrasonic air bearing. 
     
     
         13 . Vacuum gripper according to  claim 1 , characterized in that several suction ports ( 3 ) are provided, wherein a work-piece suction throttling zone ( 6 ) is formed around each of the suction ports ( 3 ).