Belt pulley and method for producing it

Patent metadata

Field	Value
Publication number	US-2016017979-A1
Application number	US-201414775028-A
Country	US
Kind code	A1
Filing date	Mar 27, 2014
Priority date	Mar 28, 2013
Publication date	Jan 21, 2016
Grant date	—

Abstract

A belt pulley ( 1 ) for a belt drive and a plastic injection molding method for producing the belt pulley are provided. The belt pulley ( 1 ) includes an anti-friction bearing ( 2 ) and a running ring ( 3 ) which surrounds the bearing outer ring ( 7 ). An end side of the running ring has a multiplicity of molding points ( 13 ) which run on the sector radii (R) of circular sectors which have a common center point on the rotational axis ( 15 ) of the belt pulley and at least two center point angles (α) of different size. Part of the circular sectors are to have sector radii, on which the molding points have cross sections of different size. Here, the center point angle of the adjacent circular sector on the side of the larger molding cross section is larger than the center point angle of the adjacent circular sector on the side of the smaller molding cross section.

First claim

1 . A belt pulley for a belt drive, comprising an anti-friction bearing and a running ring that surrounds the anti-friction bearing and is made from plastic, the anti-friction bearing including an outer ring that is injection molded, one end of the running ring has a plurality of injection molding points that run on sector radii (R) of circular sectors that have a common center point on a rotational axis of the belt pulley and at least two different size center angles (α), a part of the circular sectors include the sector radii (R) on which the injection molding points are located and have different size cross sections, and the center angle (α) of an adjacent one of the circular sectors on a side of a larger injection molding cross section is greater than a center angle (α) of an adjacent one of the circular sectors on a side of a smaller injection molding cross section.

2 . The belt pulley according to claim 1 , wherein the running ring has an inner ring, an outer ring, and a ring web connecting the inner ring to the outer ring, and on both sides of the ring web, a plurality of ribs that extend radially with non-uniform angular distribution and support the outer ring against the inner ring, and the injection molding points each run between two of the ribs on a ring bead rising from the ring web.

3 . The belt pulley according to claim 2 , wherein a number of the ribs is odd.

4 . The belt pulley according to claim 1 , wherein the injection molding points are circular and have different diameters (D) between 0.8 mm and 2.4 mm.

5 . A method for producing a belt pulley for a belt drive, comprising an anti-friction bearing and a running ring that surrounds the anti-friction bearing and is made from plastic according to claim 1 , comprising
injection molding of the anti-friction bearing outer ring with plastic in a circular ring-shaped cavity with end-side injection molding via a runner with a plurality of feed channels that run on the sector radii (R) of the circular sectors that have the common center point on the rotational axis of the belt pulley and at least two different size center angles (α), wherein a part of the circular sectors include the sector radii (R) on which feed channels with different size injection molding cross sections open into a cavity, and the center angle (α) of the circular sector adjacent on the side of the larger injection molding cross section is greater than the center angle (α) of the circular sector adjacent on the side of the smaller injection molding cross section.

Assignees

• Schaeffler Technologies Ag

Inventors

• Bell Lorenz

Classifications

• B29C45/2708

  Gates (B29C45/2703 takes precedence) · CPC title

• B29C2045/2709

  with a plurality of mould cavity inlets in close proximity · CPC title

• B29C45/0046

  Details relating to the filling pattern or flow paths or flow characteristics of moulding material in the mould cavity · CPC title

• F16H55/48 Primary

  manufactured exclusively or in part of non-metallic material, e.g. plastics  (F16H55/38, F16H55/42, F16H55/46 take precedence) · CPC title

• B29C45/1459

  Coating annular articles · CPC title