US 12,071,887 B2
Engine assembly for a vehicle having a hydrocarbon trap
Ralf Rokita, Bad Wimsbach-Neydharting (AT); Matthias Zarhuber, Thalheim bei Wels (AT); Christian Raffelsberger, Scharnstein (AT); Heinz Kusel, Pennewang (AT); Nigel Foxhall, Semriach (AT); Markus Doppelbauer, Gunskirchen (AT); Thomas Zorn, Stadl-Paura (AT); and Christian Schwab, Gratwein-Strassengel (AT)
Assigned to BRP-ROTAX GMBH & CO. KG, Gunskirchen (AT)
Appl. No. 18/255,917
Filed by BRP-ROTAX GMBH & CO. KG, Gunskirchen (AT)
PCT Filed Dec. 17, 2021, PCT No. PCT/EP2021/086426
§ 371(c)(1), (2) Date Jun. 5, 2023,
PCT Pub. No. WO2022/129482, PCT Pub. Date Jun. 23, 2022.
Claims priority of provisional application 63/126,671, filed on Dec. 17, 2020.
Prior Publication US 2024/0044274 A1, Feb. 8, 2024
Int. Cl. F01N 9/00 (2006.01); F01N 1/08 (2006.01); F01N 1/16 (2006.01); F01N 3/28 (2006.01)
CPC F01N 9/00 (2013.01) [F01N 1/083 (2013.01); F01N 1/165 (2013.01); F01N 3/28 (2013.01); F01N 2900/08 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An engine assembly for a vehicle, comprising:
an internal combustion engine comprising:
a crankcase;
a crankshaft disposed at least in part in the crankcase; and
a cylinder block connected to the crankcase,
the cylinder block defining at least one cylinder, each of the at least one cylinder defining an exhaust port for discharging exhaust gas therefrom;
and
an exhaust system for discharging exhaust gas from the engine, the exhaust system defining a first exhaust path and a second exhaust path separate from one another, the exhaust system comprising:
a catalytic converter in fluid communication with the exhaust port of the at least one cylinder to receive exhaust gas therefrom;
a main muffler downstream from and in selective fluid communication with the catalytic converter, the main muffler defining at least in part the first exhaust path;
a hydrocarbon trap downstream from and in selective fluid communication with the catalytic converter, the hydrocarbon trap defining at least in part the second exhaust path, the hydrocarbon trap comprising a hydrocarbon trapping material to adsorb hydrocarbon from exhaust gas flowing therethrough;
a pre-muffler disposed upstream from the main muffler and the hydrocarbon trap, the pre-muffler defining a pre-muffler chamber, the catalytic converter being in fluid communication with the pre-muffler chamber such that exhaust gas flows from the catalytic converter to the pre-muffler chamber before flowing through one of the first exhaust path and the second exhaust path,
the pre-muffler further comprising:
a muffler conduit to fluidly connect the pre-muffler to the main muffler, and
a trap conduit to fluidly connect the pre-muffler to the hydrocarbon trap; and
at least one exhaust path valve operable to selectively obstruct the first exhaust path and the second exhaust path to prevent exhaust gas from the catalytic converter flowing through the first exhaust path and the second exhaust path respectively, the pre-muffler enclosing the at least one exhaust path valve, each of the at least one exhaust path valve being movable between a first exhaust path position and a second exhaust path position,
the at least one exhaust path valve obstructing the second exhaust path in the first exhaust path position such that exhaust gas flows from the exhaust port of the at least one cylinder to the catalytic converter to the main muffler and to the atmosphere,
the at least one exhaust path valve obstructing the first exhaust path in the second exhaust path position such that exhaust gas flows from the exhaust port of the at least one cylinder to the catalytic converter to the hydrocarbon trap and to the atmosphere,
in the first exhaust path position, the at least one exhaust path valve blocking an inlet of the trap conduit,
in the second exhaust path position, the at least one exhaust path valve blocking an inlet of the muffler conduit.