Patent ID: 6854358

Claim:
A balance shaft unit for an internal combustion engine comprising: at least one balance shaft ( 6 , 7 ) supported in a balance casing ( 5 ) along an axis on bearing surfaces ( 31 ) of a plurality of friction bearings ( 30 ) wherein the bearing surfaces ( 31 ) are formed in the balance casing ( 5 ) itself; at least one counterweight ( 8 ) fastened to the balance shaft ( 6 , 7 ), the counterweight comprises two spaced apart ring parts ( 59 , 60 ) extending normal to the axis and define therebetween an intermediate segmental part ( 62 ) and a cutout ( 55 ), the two spaced apart ring parts ( 59 , 60 ) each have an end surface ( 61 ) wherein one of the end surfaces ( 61 ) on one of the ring parts ( 59 , 60 ) form a thrust bearing ( 32 ) with a machined surface ( 33 ) of the balance casing ( 5 ) at a location proximate to bearing surface ( 31 ).