Rotor blade and rotor for a mechanical trowel, such as a concrete polisher

Abstract

The rotor blade for a mechanical trowel, such as a concrete polisher, comprises a blade arm ( 20 ), a spacer bar ( 22 ), and a blade plate ( 24 ). The spacer bar ( 22 ) is not integral with the blade plate ( 24 ). Through-bolts ( 30 ) with nuts ( 44 ) run through unthreaded through-holes ( 32, 34, 36 ) formed in the plate ( 24 ), the spacer bar ( 22 ), and the blade arm ( 20 ). After the removal of the bolts ( 30 ), the plate ( 24 ) is separated from the spacer bar ( 22 ).

1 . Rotor blade for a mechanical trowel, such as a concrete polisher, comprising 
 a. a blade arm    b. a blade plate, and    c. a spacer bar disposed between the two,    the blade plate and the spacer bar being removably fastened to the blade arm by threaded fastening means, characterized in that the spacer bar is not integral with the blade plate, and the threaded fastening means run through unthreaded through-holes formed in at least the blade plate and the spacer bar so that the blade plate is separated from the spacer bar when the fastening means are removed.    
     
     
         2 . Blade according to  claim 1 , characterized in that the threaded fastening means are bolts inserted into threaded holes in the blade arm.  
     
     
         3 . Blade according to  claim 1 , characterized in that the threaded fastening means are bolts with nuts, also run through unthreaded through-holes formed in the blade arm.  
     
     
         4 . Blade according to  claim 3 , characterized in that the holes formed in the blade plate and the spacer bar are chamfered, and in that the bolts have heads sunk into these chamfered holes.  
     
     
         5 . Blade according to  claim 3 , characterized in that the bolts are inserted without being rotated into the holes formed in the spacer bar.  
     
     
         6 . Blade according to  claim 3 , characterized in that the nuts are cap nuts.  
     
     
         7 . Rotor blade for a mechanical trowel, such as a concrete polisher, comprising 
 a. a blade arm    b. a blade plate, and    c. a spacer bar disposed between the two, the blade plate being removably fastened to the blade arm by threaded fastening means,    characterized in that the spacer bar is not integral with the blade plate, but is integral with the blade arm, so as to form a subassembly comprising the blade arm and the spacer bar, and in that the threaded fastening means run through unthreaded through-holes formed in at least the blade plate so that the blade plate is separated from said subassembly when the fastening means are removed.    
     
     
         8 . Blade according to  claim 7 , characterized in that the threaded fastening means are bolts inserted into threaded holes in said subassembly.  
     
     
         9 . Blade according to  claim 7 , characterized in that the threaded fastening means are bolts with nuts, which also run through unthreaded through-holes formed in the blade arm and the spacer bar of the aforementioned subassembly.  
     
     
         10 . Blade according to  claim 8  or  9 , characterized in that the holes formed in the blade plate and the aforementioned subassembly are chamfered and the bolts have heads sunk into these chamfered holes.  
     
     
         11 . Blade according to  claim 9 , characterized in that the bolts are inserted without being rotated into the holes formed in the aforementioned subassembly.  
     
     
         12 . Blade according to  claim 9 , characterized in that nuts are cap nuts.  
     
     
         13 . Blade according to any of claims  7  through  12 , characterized in that the spacer bar is welded or screwed to the blade arm.  
     
     
         14 . Rotor for a mechanical trowel, such as a concrete polisher, comprising: 
 a rotor hum having at least one rotor blade comprising: 
 a. a blade arm attached to the hub, and  
 b. a blade plate located at a level lower than the hub of the rotor and removably attached by threaded fastening means to a plate-bearing part of the blade arm,  
   characterized in that the plate-bearing part of the blade arm extends vertically to a level lower than the hub of the rotor, and the threaded fastening means run through unthreaded through-holes formed in at least the blade plate.    
     
     
         15 . Rotor according to  claim 14 , characterized in that the threaded fastening means are bolts inserted into threaded holes in the plate-bearing part of the blade arm.  
     
     
         16 . Rotor according to  claim 14 , characterized in that the threaded fastening means are bolts with nuts, which also extend through unthreaded through-holes formed in the plate-bearing part of the blade arm.  
     
     
         17 . Rotor according to  claim 15  or  16 , characterized in that the holes formed in the blade plate and the plate-bearing part of the blade arm are chamfered and the bolts have heads sunk into these chamfered holes.  
     
     
         18 . Rotor according to  claim 16 , characterized in that the bolts are inserted without being rotated into the holes formed in the plate-bearing part of the blade arm.  
     
     
         19 . Rotor according to  claim 6 ,  7  or  8 , characterized in that nuts are cap nuts.  
     
     
         20 . Rotor according to any of claims  14  through  19 , characterized in that the blade arm has a cylindrical root part fitted into the hub and having a longitudinal central axis, and in that the plate-bearing part of the blade arm has a polygonal, for example hexagonal or rectangular, shape, and has a longitudinal central axis that is offset from the longitudinal central axis of the cylindrical root section.  
     
     
         21 . Rotor according to any of claims  14  through  19 , characterized in that the plate-bearing part of the blade arm has, in cross section, an upper hexagonal part and a lower part in the shape of a quadrilateral.