Feeder for punch

Abstract

A feeder is provided for a punch. The feeder includes a feeding unit, a bending unit and a transferring unit. The feeding unit feeds a roll of a metal strip that includes a leading edge. The bending unit includes a plate for bending the metal strip, a sensor for generating at least one signal on detecting the arrival of the leading edge of the metal strip at the plate and a controller for actuating the plate on receiving the signal. The transferring unit transfers the metal strip to another unit of the punch.

1 . A feeder for a punch, the feeder comprising: 
 a feeding unit for feeding a roll of a metal strip that includes a leading edge;    a bending unit comprising a plate for bending the metal strip, a sensor for generating at least one signal on detecting the arrival of the leading edge of the metal strip at the plate and a controller for actuating the plate on receiving the signal; and    a transferring unit for transferring the metal strip from the bending unit to another unit of the punch.    
   
   
       2 . The feeder according to  claim 1  wherein the operation of the plate comprises a first step and a second step.  
   
   
       3 . The feeder according to  claim 2  wherein on detecting the arrival of the leading edge of the metal strip, the sensor sends a first signal to the controller that in turn causes the plate to pivot faster than the metal strip advances so that the plate departs from the leading edge in the first step, wherein on detecting the arrival of the leading edge of the metal strip again, the sensor sends a second signal to the controller that in turn causes the plate to pivot further in the second step.  
   
   
       4 . The feeder according to  claim 1  wherein the sensor is embedded in the plate.  
   
   
       5 . The feeder according to  claim 1  wherein the plate comprises a first edge and a second edge closer to the feeding unit than the first edge is, wherein the sensor is located near the second edge.  
   
   
       6 . The feeder according to  claim 1  wherein the bending unit comprises an arm for pivoting the plate.  
   
   
       7 . The feeder according to  claim 6  wherein the bending unit comprises a mechanism for rocking the arm.  
   
   
       8 . The feeder according to  claim 7  wherein the mechanism is a cylinder.  
   
   
       9 . The feeder according to  claim 8  wherein the cylinder is hydraulic.  
   
   
       10 . The feeder according to  claim 8  wherein the cylinder is pneumatic.  
   
   
       11 . The feeder according to  claim 1  wherein the feeding unit comprises a restraint for restraining the metal strip.  
   
   
       12 . The feeder according to  claim 11  wherein the feeding unit comprises an abutting element for abutting the metal strip after the restraint.  
   
   
       13 . The feeder according to  claim 12  wherein the feeding unit comprises a guiding element for guiding the metal strip to the bending unit after the abutting element.  
   
   
       14 . The feeder according to  claim 1  wherein the transferring unit comprises at least one pair of driving rollers for rolling and driving the metal strip.  
   
   
       15 . The feeder according to  claim 14  wherein the transferring unit comprises, near the driving rollers, a group of flattening rollers for rolling and flattening the metal strip.