Supercharged internal combustion engine, particularly supercharged diesel engine for vehicular drives

Claim 1

Supercharging arrangement for internal combustion engines comprising a radial flow turbine (10) connected to the engine to receive exhaust gases therefrom, said turbine having a turbine wheel (12), the outer diameter (Da) of which is greater by at least 20 percent than the inner diameter (Di), and having a low value on nq, in which nq is defined as wherein n speed (r.p.m.); V flow volume, and H differential pressure; a supercharging rotary compressor (23) of the displacement type and having outlet valves (53); and a Foettinger torque converter of the three-element type driving said compressor from said turbine, said torque converter comprising a pump element (14) supplying fluid and having a speed-fluid supply pressure-fluid supply volume characteristic which is highly speed-dependent, said pump having a propeller with a high value of nq; a radial-flow turbine (17) element driven by the fluid pumped by said pump element and having a speed-fluid supply pressurefluid supply volume characteristic having a low degree of speed dependence, and having a value of nq which is low with respect to that of the pump element, said pump element (14) being coupled to be driven by said turbine (10) and the radial flow turbine element (17) being connected to drive a rotor of said rotary compressor (23), and a guide vane assembly element (16) for said fluid, said three elements providing for torque conversion within a predetermined range of speed ratios v between the pump element and the turbine element to drive the compressor indirectly by the exhaust gases of the internal combustion engine by means of the interposed hydrodynamic torque converter essentially independent of engine speed over wide ranges of said engine speed, the speed ratio v varying automatically in accordance with the torque balance at the shafts of the pump element and of the turbine element.