Engine system for reducing gaseous fuel slip

Patent metadata

Field	Value
Publication number	US-2016290243-A1
Application number	US-201514678543-A
Country	US
Kind code	A1
Filing date	Apr 3, 2015
Priority date	Apr 3, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

An engine system is disclosed. The engine system may have an engine including at least one cylinder. Further, the engine system may have a nozzle configured to selectively inject gaseous fuel into the at least one cylinder of the engine. The engine system may also have an intake port configured to direct air for combustion to the at least one cylinder. In addition, the engine system may have exhaust valves associated with the at least one cylinder. The exhaust valves may be configured to direct exhaust from the cylinder to an atmosphere. The exhaust valves may also be configured to close at different times.

First claim

What is claimed is:

1 . An engine system, comprising:
an engine including at least one cylinder; a nozzle configured to selectively inject gaseous fuel into the at least one cylinder of the engine; an intake port configured to direct air for combustion to the at least one cylinder; and exhaust valves associated with the at least one cylinder and configured to direct exhaust from the at least one cylinder to an atmosphere, the exhaust valves also being configured to close at different times.

2 . The engine system of claim 1 , further including a controller configured to close the exhaust valves at different times.

3 . The engine system of claim 1 , wherein the at least one cylinder includes:
a first exhaust valve configured to close at a first crank angle; and a second exhaust valve configured to close at a second crank angle greater than the first crank angle.

4 . The engine system of claim 3 , wherein
the first exhaust valve is configured to open at a third crank angle; and the second exhaust valve is configured to open at a fourth crank angle.

5 . The engine system of claim 4 , wherein the third crank angle is about equal to the fourth crank angle.

6 . The engine system of claim 3 , wherein
the at least one cylinder extends from a cylinder head end to a crankshaft end, the first exhaust valve and the second exhaust valve are disposed adjacent the cylinder head end, and the nozzle is disposed adjacent the crankshaft end.

7 . The engine system of claim 6 , further including a fuel injector configured to selectively inject liquid fuel into the at least one cylinder, the fuel injector being disposed adjacent the cylinder head end.

8 . The engine system of claim 7 , wherein
the at least one cylinder includes a side wall, the nozzle is disposed on the side wall, and at least one of the first exhaust valve and the second exhaust valve is disposed nearer the intake port than the nozzle.

9 . The engine system of claim 7 , further including a cylinder head attached to the at least one cylinder at the cylinder head end, wherein the fuel injector, the first exhaust valve, and the second exhaust valve are disposed in the cylinder head.

10 . The engine system of claim 9 , wherein
the first exhaust valve is disposed at a first diametrical distance from the intake port, and the second exhaust valve is disposed at a second diametrical distance from the intake port, the second diametrical distance being larger than the first diametrical distance.

11 . A method for reducing gaseous fuel slip, comprising:
opening exhaust valves associated with at least one cylinder of an engine to allow exhaust gases to exit the engine; opening at least one intake port during an intake stroke to allow air to enter the at least one cylinder of the engine; selectively injecting gaseous fuel into the at least one cylinder of the engine; and closing the exhaust valves at different times.

12 . The method of claim 11 , further including:
closing a first exhaust valve associated with the at least one cylinder at a first crank angle; and closing a second exhaust valve associated with the at least one cylinder at a second crank angle larger than the first crank angle.

13 . The method of claim 12 , further including:
opening the first exhaust valve at a third crank angle; and opening the second exhaust valve at a fourth crank angle.

14 . The method of claim 13 , wherein the third crank angle is about equal to the fourth crank angle.

15 . The method of claim 14 , wherein the third crank angle and the fourth crank angle are smaller than the first crank angle and the second crank angle, respectively.

16 . An engine, comprising:
an engine block; a cylinder head; a crankshaft disposed within the engine block; at least one cylinder pack, including:
a cylinder extending from a cylinder head end to a crankshaft end, the cylinder being attached to the cylinder head at the cylinder head end;
an intake port disposed on a side wall of the cylinder and configured to direct air for combustion into the cylinder;
a piston reciprocatingly disposed within the cylinder; and
a connecting rod connected at a first rod end to the piston and connected at a second rod end to the crankshaft;
a fuel injector disposed adjacent the cylinder head end and configured to inject liquid fuel into the cylinder; a nozzle configured to inject gaseous fuel into the cylinder, the nozzle being disposed on the side wall opposite the intake port; and exhaust valves associated with the cylinder and configured to direct exhaust from the cylinder to an atmosphere, the exhaust valves also being configured to close at different times.

17 . The engine of claim 16 , wherein the cylinder includes:
a first exhaust valve configured to close at a first crank angle; a second exhaust valve configured to close at a second crank angle greater than the first crank angle; a third exhaust valve configured to close at a third crank angle; and a fourth exhaust valve configured to close at a fourth crank angle greater than the second crank angle.

18 . The engine of claim 17 , wherein
the first crank angle is about equal to the third crank angle; and the second crank angle is about equal to the fourth crank angle.

19 . The engine of claim 17 , wherein the first exhaust valve, the second exhaust valve, the third exhaust valve, and the fourth exhaust valve are configured to open at a fifth crank angle.

20 . The engine of claim 17 , wherein
the at least one cylinder pack is a first cylinder pack, the engine includes a second cylinder pack, including:
a fifth exhaust valve configured to close at a fifth crank angle; and
a sixth exhaust valve configured to close at a sixth crank angle greater than the fifth crank angle, and
a first crank angle difference between the first crank angle and the second crank angle is different from a second crank angle difference between the fifth crank angle and the sixth crank angle.

Assignees

• Electro Motive Diesel Inc

Inventors

• Bandyopadhyay Deep
• Timmons John P
• Montgomery David Todd
• Foege Aaron Gamache

Classifications

• F02D13/0203 Primary

  Variable control of intake and exhaust valves · CPC title

• F02D41/0027

  the fuel being gaseous (non-electrical control F02D19/02) · CPC title

• F02D19/024

  by controlling fuel injectors · CPC title

• F02B25/145

  with intake and exhaust valves exclusively in the cylinder head · CPC title

• F02D13/0242

  Variable control of the exhaust valves only · CPC title