Device for increasing the braking power of a multi-cylinder internal combustion engine of a vehicle during an engine braking operation

摘要

A device for increasing the braking power of a multi-cylinder internal combustion engine of a vehicle during engine braking operation including a turbosupercharger and an exhaust gas turbine for each stage thereof. A respective bypass line branches off from a region of two exhaust gas header pipes that can be blocked by throttle valves. Each bypass line communicates with a nozzle bore in a turbine wall. The nozzle bores are in a plane perpendicular to a turbine wheel axis and extend either parallel next to one another or at an acute angle to and merging with one another. The nozzle bores open out into the turbine chamber directed tangentially onto the outer portion of the turbine wheel. During an engine braking operation, two partial exhaust gas streams are branched off by the bypass lines from exhaust gas retained in blocked header pipes and strike turbine wheel blades at high pressure and high speed, whereupon the turbosupercharger is driven in an accelerated manner and compressed air is supplied to combustion chambers of the engine and is there effective to increase braking power.