Tire tread wear indicator and molding device for forming a tread wear indicator

Abstract

A tire has at least one tread wear indicator. Each wear indicator is a single mark that provides continuous information to the consumer, while changing its presentation based upon the amount of tread wear. The mold blade employed to form the ear indicator has a series of stacked portions, each portion having a different configuration, the configuration being constant for the length of each portion.

1 . A tire tread for a vehicle tire, the tread having at least one tread element projecting from the base of the tread and having an defined tread depth, at least one tread element having a tread wear indicator, the wear indicator being characterized by: 
 having a series of radially stacked portions, each portion having a configuration that visually indicates the tread depth and wherein each portion has a different configuration.    
   
   
       2 . The tread of  claim 1  wherein the stacked portions have a radially innermost portion, and the configuration of the innermost portion is a warning symbol.  
   
   
       3 . The tread of  claim 1  wherein at least a single point of contact is present between radially adjacent stacked portions.  
   
   
       4 . The tread of  claim 1  wherein the different configurations are international picture symbols.  
   
   
       5 . The tread of  claim 1  wherein each portion has a consistent configuration for the radial depth of each portion.  
   
   
       6 . The tread of  claim 1  wherein the wear indicator has three radially outer portions, and the configuration in each of the three radially outer portions is a face.  
   
   
       7 . The tread of  claim 1  wherein the configuration of the radially outermost portion of the wear indicator is a smiley face.  
   
   
       8 . The tread of  claim 1  wherein the wear indicator has at most five radially adjacent stacked portions.  
   
   
       9 . A molding device for forming a tread wear indicator in a tread, the molding device comprising a mold blade, the mold blade being characterized by a series of stacked portions, each portion having a different configuration.  
   
   
       10 . The mold device of  claim 9  wherein there is at least a single point of contact between the stacked portions of the mold blade.  
   
   
       11 . The mold device of  claim 9  wherein each portion of the mold blade has a constant configuration for the length of the portion.  
   
   
       12 . The mold device of  claim 9 , the mold device further comprising a pair of pins, the pins being adjacent to the mold blade.  
   
   
       13 . The mold device of  claim 12  wherein the one pin has a greater length than the other pin.  
   
   
       14 . The mold device of  claim 9 , the mold device further comprising a tube surrounding the mold blade.  
   
   
       15 . The mold device of  claim 14  wherein for at least a portion of its length, the tube has a circular configuration.  
   
   
       16 . The mold device of  claim 14  wherein the tube has a changing cross sectional configuration.  
   
   
       17 . The mold device of  claim 14  wherein the tube has a cross sectional configuration that changes at a location corresponding to a change in configuration of the mold blade.