End connection for packing strap

Abstract

A strapping connection for a pair of longitudinally extending and transversely overlapping strap ends has a pair of longitudinally extending and interengaging hook formations formed as transversely pushed-out regions of the strap ends and permitting limited movement of the strap ends in one longitudinal direction. In addition the ends are formed in the pair of hook formations with transversely interengaging lock formations fitting transversely snugly together and prohibiting relative longitudinal movement of the strap ends.

We claim:  
     
         1 . A strapping connection for a pair of longitudinally extending and transversely overlapping strap ends, the connection comprising: 
 a pair of longitudinally extending and interengaging hook formations formed as transversely pushed-out regions of the strap ends and permitting limited movement of the strap ends in one longitudinal direction; and    transversely interengaging lock formations fitting transversely snugly together, prohibiting relative longitudinal movement of the strap ends, and formed in the pair of hook formations.    
     
     
         2 . The strapping connection defined in  claim 1 , further comprising 
 a second pair of longitudinally extending and interengaging end hook formations spaced longitudinally from the first-mentioned pair, formed as transversely pushed-out regions of the strap ends, permitting limited movement of the strap ends in one longitudinal direction, and free of the lock formations.    
     
     
         3 . The strapping connection defined in  claim 1  wherein the lock formations are formed as interfitting dimples.  
     
     
         4 . The strapping connection defined in  claim 3  wherein the dimples are pyramidal.  
     
     
         5 . The strapping connection defined in  claim 3  wherein the dimples are conical.  
     
     
         6 . The strapping connection defined in  claim 1  wherein the lock formations pierce completely through one of the strap ends.  
     
     
         7 . The strapping connection defined in  claim 1  wherein each hook formation has an end portion defined between a pair of closely spaced and longitudinally extending cuts, another end portion spaced longitudinally from the one end portion and defined between a pair of widely spaced and longitudinally extending cuts, and an intermediate portion between the end portions and formed between a pair of angled cuts each connecting a respective one of the closely spaced cuts with a respective one of the widely spaced cuts.  
     
     
         8 . The strapping connection defined in  claim 7  wherein the lock formations are formed between the widely spaced cuts.  
     
     
         9 . The strapping connection defined in  claim 1  wherein the lock formations project transversely by a distance equal at least to a thickness of the strap ends.  
     
     
         10 . A method of joining a pair of longitudinally extending and transversely overlapping strap ends, the method comprising the steps of: 
 pushing regions out of the overlapping strip ends to form a pair of longitudinally extending and interengaging hook formations permitting limited movement of the strap ends in one longitudinal direction; and    a forming in the pair of hook formations transversely interengaging lock formations fitting transversely snugly together and prohibiting relative longitudinal movement of the strap ends.    
     
     
         11 . The method defined in  claim 10 , further comprising the step of 
 forming two further pairs of end hook formations longitudinally flanking the first-mentioned pair of hook formations.    
     
     
         12 . An apparatus for joining a pair of longitudinally extending and transversely overlapping strap ends, the apparatus comprising: 
 means including an interengaging die and punch tools having wavy faces for pushing regions out of the overlapping strip ends a pair of longitudinally extending and interengaging hook formations permitting limited movement of the strap ends in one longitudinal direction and a pin set in one of the tools for forming in the pair of hook formations transversely interengaging lock formations fitting transversely snugly together and prohibiting relative longitudinal movement of the strap ends.    
     
     
         13 . The apparatus defined in  claim 12  wherein the pin has a width generally equal to a width of a cavity of the die tool and an end formed with a tapered end.  
     
     
         14 . Th apparatus defined in  claim 13  wherein the tapered end has a flat end face.  
     
     
         15 . The apparatus defined in  claim 13  wherein the pin is set in the punch tool and the cavity is formed with a recess in which the pin can fit loosely when the die tool and punch tool are fitted together.  
     
     
         16 . The apparatus defined in  claim 13  wherein the pin is of hardened steel.