Working station of a machine processing plate elements

Abstract

A working station for a machine for processing plate-like elements having a front end. A working tool supported on the machine frame has a trailing end in a feed direction of the plate-like elements. A transverse gripper bar extending across the working station has at least one gripper for seizing the leading edge of the sheet. A drive device at one end of the gripper bar with two flexible drive chains at opposite ends drives the gripper bar. The gripper bar is guided down toward the downstream end of the working tool when the gripper bar crosses the downstream end of the working tool, by transverse link axles connected with the chain, to a cam sensor or follower and a lever arm between axles. A cam surface on the frame contacts the cam sensor as the gripper bar passes the end of the working station and urges the cam sensor, the lever arm and the gripper bar to swivel down toward the working tool. At the end of the cam surface, the cam sensor and the gripper bar are urged upwardly off the working surface.

1 . A working station for a machine for processing plate-like elements, the working station comprising: 
 a frame;    a working tool supported on the frame and onto which a plate-like element may be arranged;    a gripper bar extending transversely of the working tool and including an element for seizing the leading edge of a sheet of plate-like element as it is advanced over the working tool;    a flexible drive device attached to the gripper bar for advancing the gripper bar and thereby advancing the plate-like element;    a drive for the flexible drive device and supported on the frame;    the gripper bar being movable toward the working tool and with respect to the flexible drive as the gripper bar crosses the downstream end of the working tool during advancing of the flexible drive and the gripper bar;    at least one transverse link axle connected with the flexible drive;    a cam sensor movable toward and away from the working tool;    a lever arm connecting the at least one link axle with the cam sensor and the cam sensor being swivellable about the at least one link axle, a pull-back device for maintaining the lever arm and the cam sensor in a determined position about the at least one transverse link axle;    a gripper bar lowering cam attached to the frame and extending in the feed direction of the plate-like element and having a cam surface placed to intersect the trajectory of the cam sensor as the flexible drive device and the cam sensor are advanced to the feed direction, the cam surface being-positioned that upon contacting the sensor cam, the cam surface swivels the cam sensor toward the working surface and swivels the gripper bar and the sensor cam about the at least one link axle for temporarily moving the gripper and the leading edge of the sheet toward the working tool.    
     
     
         2 . The working station of  claim 1 , further comprising a guide element in the feed direction of the plate-like element for contacting the cam sensor and for swiveling the cam sensor and the gripper bar back off the working tool after the cam sensor has passed the lowering cam.  
     
     
         3 . The working station of  claim 1 , wherein the at least one link axle comprises a first link axle and a second link axle, the cam sensor being swivellable about the first axle.  
     
     
         4 . The working station of  claim 2 , wherein the second axle supports the cam sensor roller.  
     
     
         5 . The working station of  claim 4 , wherein the cam sensor is a roller.  
     
     
         6 . The working station of  claim 1 , wherein the gripper bar has opposite lateral sides and the flexible drive device comprises two flexible drive devices attached at opposite ends of the gripper bar and movable together.  
     
     
         7 . The working station of  claim 6 , wherein the drive devices are shaped like endless loops guided in an endless continuous path.  
     
     
         8 . The working station of  claim 7 , wherein the drive devices are chains.  
     
     
         9 . The working station of  claim 6 , wherein: 
 the at least one link axle comprises a first link axle and a second link axle, the cam sensor being swivellable about the first axle;    the second axis supports the cam sensor roller;    the flexible drive device is a chain to which the first and second link axle is attached;    chain guides attached to the frame and in contact with the chain, the chain guides are shaped for enabling swiveling of the gripper bar held at the second axle around the first link axle supported on the chain guide when the cam sensor contacts the cam surface.    
     
     
         10 . The working station of  claim 3 , wherein the first link axle leads to the second link axle along the feed direction of the plate-like elements.  
     
     
         11 . The working station of  claim 3 , wherein the cam sensor is located in the vicinity of the rear link axle between the gripper bar and the chain guide.