ENGINE INTAKE AND EXHAUST SYSTEM AND INTERNAL COMBUSTION ENGINE
FIG6 is a side view of an upper part of the engine
As illustrated in FIG6, the upstream-side intake pipe 3 constituting the intake passage has a declined part 3a obliquely inclining toward the compressor 2b of the turbocharger 2. Thus, the EGR pipe 16 constituting the EGR passage has a curve 16a in an intermediate part thereof and is connected to the obliquely declined part 3a of the upstream-side intake pipe 3 via the EGR valve 17. A blow-by gas introduction pipe 31 which introduces the blow-by gas of the engine into the intake passage is connected to the obliquely declined part 3a of the upstream-side intake pipe 3.
side view
24
supply pipe
17
EGR valve
31
gas introduction pipe
16
EGR pipe
3
pipe
13
curved pipe
['1. An intake and exhaust system for an engine (1), comprising: an exhaust gas recirculation (EGR) passage (15, 16, 17) configured to recirculate a portion of exhaust gas as EGR gas, from an exhaust passage (2a, 11, 12, 13, 14) of the engine (1) to an intake passage (2b, 3, 4, 5, 8); and an EGR cooler (15) disposed in the EGR passage (15, 16, 17), the EGR cooler (15) being coupled to a passage wall of the exhaust passage (2a, 11, 12, 13, 14) at an EGR gas inlet side, and having a center line intersecting with a flow direction of exhaust gas in the exhaust passage (2a, 11, 12, 13, 14), wherein a through-hole (18) communicating the EGR cooler (15) with the exhaust passage (2a, 11, 12, 13, 14) is a long hole (18) elongated substantially in the flow direction in the exhaust passage (2a, 11, 12, 13, 14), wherein an exhaust gas purifier (12) is provided in an intermediate part of the exhaust passage (2a, 11, 12, 13, 14), wherein the exhaust gas passage (2a, 11, 12, 13, 14) has a curved pipe (13) on a downstream side of the exhaust gas purifier (12) in the flow direction to change the flow direction, wherein the through-hole (18) communicating the EGR cooler (15) with the exhaust passage (2a, 11, 12, 13, 14) opens to a passage wall of the curved pipe (13) of the exhaust passage (2a, 11, 12, 13, 14) at an outer circumferential side of the curve of the exhaust passage on an upper surface of the curved pipe (13), and the EGR cooler (15) is directly attached to the curved pipe (13).']