Bearing unit for use in an axlebox of a railway vehicle and axlebox including the same

Abstract

The invention relates to a bearing unit for use in an axlebox of a railway vehicle, including a bearing having an inner ring and a metallic outer ring and rolling elements arranged therebetween. The bearing is configured to support an axle of said railway vehicle. Further, a sleeve surrounding the outer ring of the bearing is provided. It is proposed that the sleeve is made of a non-metallic material.

1 . A bearing unit for use in an axlebox of a railway vehicle, the unit comprising:
 a bearing having an inner ring and a metallic outer ring and rolling elements arranged therebetween,   the bearing being configured to support an axle of the railway vehicle,   a sleeve surrounding the outer ring of the bearing; and   the sleeve being made of a non-metallic material.   
     
     
         2 . The bearing unit according to  claim 1 , wherein the sleeve is made of a polymer material. 
     
     
         3 . The bearing unit according to  claim 1 , wherein the sleeve is directly moulded onto said outer ring. 
     
     
         4 . The bearing unit according to  claim 1 , wherein the outer ring has a non-cylindrical outer surface. 
     
     
         5 . The bearing unit according to  claim 1 , wherein an outer surface of the outer ring has a concave portion in an axial cross-section. 
     
     
         6 . The bearing unit according to  claim 1 , wherein the bearing is a double-row angular contact roller bearing, wherein a thickness of said outer ring is basically constant over a width of two outer raceways of the outer ring. 
     
     
         7 . The bearing unit according to  claim 1 , wherein the sleeve has a flat portion in its outer surface. 
     
     
         8 . The bearing unit according to  claim 1 , wherein the outer ring is split in two parts and being simultaneously overmoulded with the same material used to fabricate the sleeve. 
     
     
         9 . The bearing unit according to  claim 8 , wherein a distance element is arranged between the two parts of the outer ring. 
     
     
         10 . The bearing unit according to  claim 1 , wherein an outer surface of the sleeve has a polygonal cross-section. 
     
     
         11 . An axlebox for railway vehicles, including:
 a bearing having an inner ring and a metallic outer ring and rolling elements arranged therebetween,   the bearing being configured to support an axle of the railway vehicle,   a sleeve surrounding the outer ring of the bearing; and   the sleeve being made of a non-metallic material; and   a metallic axlebox hosing accommodating the sleeve with the bearing, wherein   at least a part of the axlebox housing is configured to remain connected with a suspension of the railway vehicle when the axle is disconnected from the railway vehicle for maintenance.   
     
     
         12 . An axlebox according to  claim 9 , further comprising means for mounting a front cover of the axle box, wherein the means for mounting the axlebox are arranged provided in the sleeve.