Exhaust gas recirculation device

Abstract

The present invention relates to an exhaust gas recirculation device (6) for an internal combustion engine (1), in particular in a motor vehicle. The exhaust gas recirculation device (6) includes a recirculation line (7) and a fresh gas line section (8) in which a Venturi nozzle (10) is designed in its inlet area (9). The recirculation line (7) opens into the fresh gas line section (8) in a low pressure area (11) of the Venturi nozzle (10).

Description

The drawings show schematically in each case

FIG. 1 a basic diagram like a wiring diagram of an internal combustion engine having exhaust gas recirculation,

FIG. 2 a partial sectional perspective view of an exhaust gas recirculation device,

FIG. 3 a view like that in FIG. 2 but from a different direction of view,

FIGS. 4 to 6 views like that in FIG. 2 but each showing different embodiments.

Claims

1. An exhaust gas recirculation device for an internal combustion engine (1), in particular in a motor vehicle having at least one recirculation line (7),having a fresh gas line section (8) in which a Venturi nozzle (10) is designed in an inlet area (9),whereby the at least one recirculation line (7) opens into the fresh gas line section (8) in a low pressure range (11) of the Venturi nozzle (10),whereinthe Venturi nozzle (10) has a variable flow cross section.

2. The exhaust gas recirculation device according to claim 1, whereina control device (20) for adjusting the flow cross section of the Venturi nozzle (10) is provided.

3. The exhaust gas recirculation device according to claim 1, whereinthe Venturi nozzle (10) has at least one adjustable wall section (21) which is adjustable with regard to its distance with respect to an opposite wall section (22) and/ora mouth opening (33) through which the recirculation line (7) opens into the fresh gas line section (8) is arranged in the opposite wall section (22).

4. The exhaust gas recirculation device according to claim 3, whereinthe adjustable wall section (21) is formed by an elastically bendingly deformable membrane (25) which is attached to the fresh gas line section (8) on its end sections (26, 27) spaced a distance apart from one another in the direction of flow (23) of the Venturi nozzle (10),the membrane (25) is attached with at least one of its end sections (27) to the fresh gas line section (8) in the direction of flow (23) so that it is displaceable in relation to the fresh gas line section (8).

5. The exhaust gas recirculation device according to claim 2whereinthe control device (20) is drive-coupled to the adjustable wall section (21) and/orthe control device (20) has a control member (29) that is drive-coupled to the membrane (25) and/orthe control member (29) is arranged exclusively on a side of the membrane (25) facing away from the flow path (37) leading through the Venturi nozzle (10) and/orthe control member (29) penetrates through the membrane (25) across the direction of flow (23) of the Venturi nozzle (10) and has a valve member (36) for controlling a mouth opening (33) of the recirculation line (7) and/orthe control member (29) is adjustable in stroke across the direction of flow (23) of the Venturi nozzle (10) and/orthe control member (29) is drive-coupled to the adjustable wall section (21) or to the membrane (25) via an entraining arrangement (30, 31) so that the control member (29) entrains the adjustable wall section (21) or the membrane (25) only after a predetermined return stroke.

6. The exhaust gas recirculation device according to claim 3, whereinthe adjustable wall section (21) is attached to the fresh gas line section (8) so that it can pivot about a pivot axis (40) running across the direction of flow (23) of the Venturi nozzle (10) on an upstream or downstream end section (27) and/orthe adjustable wall section (21) is stiff or rigid.

7. The exhaust gas recirculation device according to claim 2, whereinthe control device (20) is drive-coupled to the adjustable wall section (21) in the area of the other end section (26) and/orthe control device (20) has a wedge-shaped control member (29) that is adjustable parallel to the direction of flow (23) in relation to the fresh gas line section (8) and cooperates with the other end section (26) of the adjustable wall section (21) and pivots it more or less about the pivot axis (40) depending on its relative position.

8. The exhaust gas recirculation device according to claim 3, whereinthe adjustable wall section (21) has two partial wall sections (45, 46) overlapping one another in the direction of flow (23) of the Venturi nozzle (10),the first partial wall section (45) is mounted on the fresh gas line section (8) so it can pivot about a pivot axis (48) running across the direction of flow (23) on an end section (47) at a distance from the second partial wall section (46),the second partial section (46) is attached to a shaft (50) on an end section (49) at a distance from the first partial wall section (45), said shaft being arranged on the fresh gas line section (8) to rotate about an axis of rotation (51) running across the direction of flow (43).

9. The exhaust gas recirculation device according to claim 2, whereinthe control device (20) is drive-coupled to the shaft (50) and/orthe second partial wall section (46) entrains the first partial wall section (45) in pivoting or entrains against the spring force and/orthe second partial wall section (46) slides on the first partial wall section (45) in the overlap area (54) and/orthe overlap area (54) is designed in the area of the narrowest flow cross section of the Venturi nozzle (10).

10. The exhaust gas recirculation device according to claim 1, whereinthe at least one recirculation line (7) opens into the fresh gas line section (8) in the area of the narrowest flow cross section of the Venturi nozzle (10) and/orthe at least one recirculation line (7) has a mouth section (38) opening into the fresh gas line section (8), its longitudinal direction running essentially across the direction of flow (23) of the Venturi nozzle (10) and/orthe at least one recirculation line (7) has a mouth section (38) opening into the fresh gas line section (8) and arranged in the interior of the fresh gas line section (8), its longitudinal direction running essentially parallel to the direction of flow (23)of the Venturi nozzle (10) and/orthe Venturi nozzle (10) has essentially a rectangular profile with a cross-sectional area that varies in the direction of flow (23) across its direction of flow (23).

11. The exhaust gas recirculation device according to claim 1, whereinthe recirculation line (7) is connected to an exhaust line (5) of the internal combustion engine (1) upstream from a turbine (16) of the exhaust gas turbocharger (15) and/orthe fresh gas line section (8) is installed in a fresh gas line (4) of the internal combustion engine (1) downstream from a charger (13), in particular a compressor (14) of an exhaust gas turbocharger (15).