Lubricant level control in vehicle driving head assemblies

摘要

A prefabricated shield is configured to be fitted around at least a portion of crown wheel (102) in a vehicle driving head assembly. The shield defines a mouth into which at least an external portion of the crown wheel is intended to extend, to provide a cover for a portion of the crown wheel. The shield defines a working clearance with the crown wheel, in use. A temperature controlled valve (140) for regulating the flow of lubricant into the shield in relation to the temperature of lubricant adjacent the shield. A heater is provided for heating the lubricant in cold conditions.