Pierce nut manufacturing method and apparatus

Abstract

The present invention is premised upon method of manufacturing rolled pierce nuts having a predetermined profile from a metal rod, more particularly to a method and apparatus delivering greater manufacturing flexibility through the use of multiple stations with flexible inputs and outputs.

1 . A method of manufacturing rolled pierce nuts having a predetermined profile from a metal rod comprising the steps of:
 a. providing a articulating die including a punching station for punching a through-hole in the rod, a counter-sinking station for counter-sinking a least a portion of the through hole and a final trim station for cutting a blank nut to length;   b. advancing the rod through the punching station and punching the through-hole;   c. advancing the rod through the counter-sinking station and creating the counter-sunk portion of the through-hole;   d. advancing the rod through the final trim station and cutting the blank nut to length;   e. providing a hole sensor disposed after the final trim station for detecting the presence of the through-hole;   f. providing a first hopper to collect blank nuts;   g. advancing the blank nut past the hole sensor;   h. removing the blank nut if a non-compliant hole is detected;   i. advancing the blank nut into the first hopper if a compliant hole is detected;   j. providing a tapper station for tapping the through-hole of the blank nut;   k. advancing the blank nut from the first hopper to the tapper station;   l. tapping a thread into the through-hole creating a tapped nut;   m. providing a thread sensor after the tapper station for detecting the presence of the thread in the tapped nut;   n. providing a second hopper to collect tapped nuts;   o. advancing the tapped nut past the thread sensor;   p. removing the tapped nut if a non-compliant thread is detected;   q. advancing the tapped nut into the second hopper if a compliant thread is detected;   r. providing at least one frangible wire;   s. providing a cinching tool station to cinch the at least one frangible wire to the tapped nut creating a cinched pierce nut;   t. providing a spooling station;   u. advancing the tapped nut and the at least one frangible wire to the cinching tool station;   v. cinching the tapped nut to the at least one frangible wire;   w. advancing the cinched pierce nut to the spooling station; and   x. spooling the cinched pierce nut, thus creating the rolled pierce nuts.   
     
     
         2 . The method according to  claim 1 , further including the step of removing the blank nuts from the first hopper to perform at least one first derivative operation on the blank nuts. 
     
     
         3 . The method according to  claim 2 , further including the step of performing at least one first derivative operation on the blank nut, thus creating a modified bank nut. 
     
     
         4 . The method according to  claim 3 , further including the step of returning the modified blank nut to the first hopper, the second hopper or both. 
     
     
         5 . The method of  claim 3  wherein the at least one first derivative operation is selected from the group consisting of plating, drilling, painting, inspecting, heat treating; annealing; and de-burring. 
     
     
         6 . The method according to  claim 1 , further including the step of removing the tapped nuts from the first hopper to perform at least one second derivative operation on the tapped nuts. 
     
     
         7 . The method according to  claim 6 , further including the step of performing at least one second derivative operation on the blank nut, thus creating a modified tapped nut. 
     
     
         8 . The method according to  claim 7 , further including the step of returning the modified tapped nut to the first hopper, the second hopper or both. 
     
     
         9 . The method of  claim 7  wherein the at least one second derivative operation is selected from the group consisting of plating, drilling, painting, inspecting, heat treating; annealing; and de-burring.