US Patent 10550772 Camshaft assembly and method of operating the same

A camshaft assembly for an internal combustion engine of a vehicle and method of operating the camshaft assembly to enhance engine braking performance through selective activation of a cam lobe having a brake gas recirculation contour. The camshaft assembly comprises an exhaust camshaft and a lobe pack on the exhaust camshaft, with the lobe pack including a plurality of cam lobes. At least one cam lobe of the plurality of cam lobes includes a brake gas recirculation cam contour having an exhaust stroke projection and a combustion stroke projection. The method switches to the cam lobe including the brake gas recirculation profile when certain criteria indicate that an engine braking mode is to be activated.