Gearwheel and method for manufacturing a gearwheel

Abstract

The invention concerns a gearwheel ( 1 ) with a gear rim ( 2 ) and an insert ( 3 ) whose external diameter (d 3 ) is greater than half of the external diameter (d 1 ) of the gearwheel ( 1 ), wherein the insert ( 3 ) is surrounded by injection molding by means of a cone mold during the manufacture of the gearwheel. In particular, the gear rim ( 2 ), including gear teeth on the external circumference, is formed at the same time during the injection molding process.

1 . Gearwheel ( 1 ) with 
 a gear rim ( 2 ) and    an insert ( 3 ), whose external diameter (d 3 ) is greater than half of the external diameter (d 1 ) of the gearwheel ( 1 ),    characterized in that    the insert ( 3 ) is surrounded by injection molding by means of a cone mold.    
   
   
       2 . Gearwheel according to  claim 1 , in which the gear rim ( 2 ) is formed by means of the cone mold as a component surrounding the insert.  
   
   
       3 . Gearwheel according to  claim 1 , in which the gear rim ( 2 ), including an external gear structure ( 21 ), is formed by means of a cone mold.  
   
   
       4 . Gearwheel according to  claim 3 , in which the insert ( 3 ) has indentations ( 32 ,  33 ) facing outward toward the gear rim ( 2 ), into which the material of the gear rim ( 2 ) penetrates.  
   
   
       5 . Gearwheel according to  claim 4 , in which at least one part of the indentations is formed as globoid-shaped indentations ( 33 ).  
   
   
       6 . Gearwheel according to  claim 1 , in which the insert ( 3 ) has off-center protrusions ( 34 ) facing outward toward the gear rim ( 2 ) which penetrate into the material of the gear rim ( 2 ).  
   
   
       7 . Gearwheel according to  claim 6 , in which at least one part of the off-center protrusions ( 34 ) is formed with an oblong extension transverse to a rotational direction.  
   
   
       8 . Gearwheel according to  claim 6 , in which at least one part of the off-center protrusions ( 34 ) is arrayed in a displaced configuration off-center to the gate side of the cone mold.  
   
   
       9 . Gearwheel according to  claim 1 , in which the insert ( 3 ) is made of metal and the external part ( 3 ) is made of plastic.  
   
   
       10 . Gearwheel according to  claim 1 , in which the insert ( 3 ) is surrounded by injection molding with a metallic material.  
   
   
       11 . Method for manufacturing a gearwheel ( 1 ) with a gear rim ( 2 ) and with an insert ( 3 ) whose external diameter (d 3 ) is greater than half of the external diameter (d 1 ) of the gearwheel ( 1 ), 
 characterized in that    the insert ( 3 ) is surrounded by injection molding by means of a cone mold.    
   
   
       12 . Method according to  claim 11 , in which the gear rim ( 2 ) is formed by means of the cone mold as the component surrounding the insert.  
   
   
       13 . Method according to  claim 11 , in which a lateral molded part is created by means of a cone mold on an insert wall in a direction axial to the insert ( 3 ).  
   
   
       14 . Method according to  claim 11 , in which a lateral part created in an axial direction by means of the cone mold is detached.  
   
   
       15 . Method according to  claim 11 , in which the gear rim ( 2 ), including an external gear structure ( 21 ), is formed by means of the cone mold.  
   
   
       16 . Method according to  claim 11 , in which the cone gate is designed with thick walls, specifically with a width on the side of the insert ( 3 ) of more than 60%, particularly from approximately 60% up to 150% or more, of a maximum wall thickness of the gear rim ( 2 ).