Rush for automatic motor vehicle washing systems

Abstract

The present invention relates to a brush which has been specifically designed for automatic motor vehicle washing systems, which comprises a bristle supporting layer ( 1 ) which can be wound about a shaft. The main feature of the invention is that the bristles ( 2 ) are made by extruding a closed cell foamed plastics material.

1  A brush for automatic motor vehicle washing systems, comprising a bristle supporting layer ( 1 ) which can be wound about a shaft, the brush bristles ( 2 ) being made of an extruded closed cell foamed plastics material, characterized in that said closed cell foamed plastics material is made by foaming polyethylene or polypropilene by using, as a foaming agent, a modified azodicarbonamide, dispersed in high fluidity polyethylene, and in a rate from 1.5% to 2% based on the cell foamed plastics material, at a foaming temperature from 160° C. to 190° C. in an extruder having the following temperature pattern: 
 140° C. at the feeding region of said extruder;  
 175°-180° C. at the central region of said extruder; and  
 160° C. at the head of said extruder;  
 said temperatures varying within ±15%.  
 
     
     
         2 . A brush according to  claim 1 , characterized in that said foamed plastics material bristles ( 2 ) have a density from 300 to 700 kg/m 3 .  
     
     
         3 . A brush, according to  claim 1 , characterized in that said foamed plastics material bristles have a density of 500 kg/m 3 .  
     
     
         4 . A brush, according to  claim 1 , characterized in that said bristles have an opposite double trapezium shaped cross section.  
     
     
         5 . A brush, according to  claim 1 , characterized in that said bristles have a square-shape cross section.  
     
     
         6 . A brush, according to  claim 1 , characterized in that said bristles have a rectangular-shape cross section.  
     
     
         7 . A brush, according to  claim 1 , characterized in that said bristles have a circular shape cross-section.  
     
     
         8 . A brush, according to  claim 1 , characterized in that said bristles have an oval shape cross-section.