Engine system

Patent metadata

Field	Value
Publication number	US-2016369709-A1
Application number	US-201514939967-A
Country	US
Kind code	A1
Filing date	Nov 12, 2015
Priority date	Jun 19, 2015
Publication date	Dec 22, 2016
Grant date	—

Abstract

An engine system includes main exhaust ports fluidly communicating with each combustion chamber. An exhaust variable valve lift apparatus controls an operation of a main exhaust valve which closes or opens each main exhaust port. A main exhaust manifold is connected with the main exhaust ports. Scavenge exhaust ports fluidly communicate with each combustion chamber. A variable scavenge apparatus controls an operation of a scavenge valve which closes and opens each scavenge exhaust port. A scavenge manifold is connected with the scavenge exhaust ports. A controller is configured to control operations of the exhaust variable valve lift apparatus and the variable scavenge apparatus according to a vehicle operation state.

First claim

What is claimed is:

1 . An engine system comprising:
main exhaust ports fluidly communicating with each combustion chamber; an exhaust variable valve lift apparatus controlling an operation of a main exhaust valve which closes or opens each main exhaust port; a main exhaust manifold connected with the main exhaust ports; scavenge exhaust ports fluidly communicating with each combustion chamber; a variable scavenge apparatus controlling an operation of a scavenge valve which closes and opens each scavenge exhaust port; a scavenge manifold connected with the scavenge exhaust ports; and a controller configured to control operations of the exhaust variable valve lift apparatus and the variable scavenge apparatus according to a vehicle operation state.

2 . The engine system of claim 1 , wherein the exhaust variable valve lift apparatus is selectively operated in a short duration mode and in a long duration mode of which an opening duration of the main exhaust valve is longer than that of the short duration mode according to the control of the controller, and
wherein the variable scavenge apparatus is selectively operated in a normal mode and a cylinder de-activation (CDA) mode of which the scavenge valve is closed according to the control of the controller.

3 . The engine system of claim 2 , wherein according to the vehicle operation state, the controller controls the exhaust variable valve lift apparatus to be operated in the short duration mode and the variable scavenge apparatus to be operated in the normal mode.

4 . The engine system of claim 2 , wherein when the exhaust variable valve lift apparatus is operated in the short duration mode, a closing time of the main exhaust valve is earlier than an exhaust top dead center, and
wherein when the exhaust variable valve lift apparatus is operated in the long duration mode, the closing time of the main exhaust valve is later than the exhaust top dead center.

5 . The engine system of claim 2 , wherein when the variable scavenge apparatus is operated in the normal mode, the scavenge valve is opened later than an opening time of the main exhaust valve and is closed later than a closing time of the main exhaust valve.

6 . The engine system of claim 5 , wherein a valve lift and a valve duration of the scavenge valve are smaller than those of the main exhaust valve.

7 . The engine system of claim 5 , wherein the scavenge valve is opened near an exhaust top dead center.

8 . The engine system of claim 1 , wherein valve profiles of the scavenge valve and the main exhaust valve are crossed at a valve lift of less than 2.0 mm.

9 . The engine system of claim 1 , wherein valve profiles of the scavenge valve and an intake valve are crossed at a valve lift of more than 80% of a maximum lift of the scavenge valve.

10 . The engine system of claim 1 , further comprising: a turbocharger,
wherein exhaust gas passing through the main exhaust manifold passes through a turbine of the turbocharger, and a part of the exhaust gas passing through the scavenge manifold passes through a compressor of the turbocharger before entering the combustion chamber.

11 . The engine system of claim 1 , further comprising: an exhaust gas recirculation (EGR) cooler, and
wherein a part of the exhaust gas passing through the scavenge manifold passes through the EGR cooler before entering the combustion chamber.

12 . The engine system of claim 1 , wherein the scavenge exhaust port has a diameter smaller than that of the main exhaust port.

13 . The engine system of claim 2 , wherein according to the vehicle operation state, the controller controls the exhaust variable valve lift apparatus to be operated in the long duration mode and the variable scavenge apparatus to be operated in the CDA mode.

14 . An engine system comprising:
main exhaust ports fluidly communicating with each combustion chamber; an exhaust variable valve lift apparatus controlling an operation of a main exhaust valve which closes or opens each main exhaust port; a main exhaust manifold connected with the main exhaust ports; scavenge exhaust ports fluidly communicating with each combustion chamber; a variable scavenge apparatus controlling an operation of a scavenge valve which closes and opens each scavenge exhaust port; a scavenge manifold fluidly connected with the scavenge exhaust ports; an engine operation state detecting portion including an rpm sensor; and a controller configured to control operations of the exhaust variable valve lift apparatus and the variable scavenge apparatus according to an output signal of the engine operation state detecting portion.

15 . The engine system of claim 14 , wherein the exhaust variable valve lift apparatus is selectively operated in a short duration mode and a long duration mode of which an opening duration of the main exhaust valve is longer than an opening duration of the short duration mode according to the control of the controller, and
wherein the variable scavenge apparatus is selectively operated in a normal mode and a CDA mode of which the scavenge valve is closed according to the control of the controller.

16 . The engine system of claim 15 , wherein the controller controls the exhaust variable valve lift apparatus to be operated in the short duration mode and the variable scavenge apparatus to be operated in the normal mode according to an vehicle operation state including an rpm signal, and
wherein the controller controls the exhaust variable valve lift apparatus to be operated in the long duration mode and the variable scavenge apparatus to be operated in the CDA mode according to the vehicle operation state.

17 . The engine system of claim 15 , wherein when the variable scavenge apparatus is operated in the normal mode, the scavenge valve is opened later than an opening time of the main exhaust valve and is closed later than a closing time of the main exhaust valve.

18 . The engine system of claim 17 , wherein the scavenge valve has smaller valve lift and valve duration than those of the main exhaust valve;
wherein the scavenge valve is opened near an exhaust top dead center; and wherein valve profiles of the scavenge valve and the main exhaust valve are crossed at a valve lift of less than 2.0 mm.

19 . The engine system of claim 17 , wherein valve profiles of the scavenge valve and an intake valve are crossed at a valve lift of more than 80% of a maximum lift of the scavenge valve.

20 . The engine system of claim 17 , wherein the scavenge exhaust port has a smaller diameter than that of the main exhaust port.

Assignees

• Hyundai Motor Co Ltd

Inventors

• Choi Byong Young

Classifications

• F01N13/107

  More than one exhaust manifold or exhaust collector · CPC title

• F02M26/23

  Layout, e.g. schematics · CPC title

• F02D13/0276 Primary

  Actuation of an additional valve for a special application, e.g. for decompression, exhaust gas recirculation or cylinder scavenging · CPC title

• F02D13/0249

  changing the valve timing only · CPC title

• F02M26/41

  characterised by the arrangement of the recirculation passage in relation to the engine, e.g. to cylinder heads, liners, spark plugs or manifolds; characterised by the arrangement of the recirculation passage in relation to specially adapted combustion chambers · CPC title