System and method for warming an emissions device of an engine exhaust system

Patent metadata

Field	Value
Publication number	US-11401875-B2
Application number	US-202016798163-A
Country	US
Kind code	B2
Filing date	Feb 21, 2020
Priority date	Feb 21, 2020
Publication date	Aug 2, 2022
Grant date	Aug 2, 2022

Abstract

Methods and systems for increasing exhaust gas temperatures of an engine are described. In one example, engine exhaust gas temperatures may be increased via deactivating cylinders and flowing exhaust gases through deactivated cylinder. Engine pumping losses may be reduced via the exhaust gases that flow through the deactivated cylinder so as to reduce engine fuel consumption while heating an exhaust gas after treatment device.

First claim

The invention claimed is:

1. An engine operating method, comprising:
deactivating a cylinder via ceasing fuel flow thereto and holding an intake poppet valve of the cylinder open for an entire duration of a cycle of an engine that includes the cylinder;
operating an exhaust valve of the cylinder during the cycle; and
adjusting a port throttle to a partially open position for the entire duration of the cycle of the engine.

2. The engine method of claim 1 , where holding the intake poppet valve of the cylinder open for the entire duration of the cycle of the engine includes holding the intake poppet valve open a threshold lift amount.

3. The engine method of claim 2 , further comprising increasing lift of the intake poppet valve above the threshold lift amount to follow an intake poppet valve lift amount generated from a base cam lift profile during an intake stroke of the cycle.

4. The engine method of claim 1 , where the cylinder is deactivated in response to a request to heat an after treatment device, and where the intake poppet valve is open less than a squish height of the cylinder plus a valve recess plus a depth of a piston valve pocket.

5. The engine method of claim 4 , further comprising at least partially closing a central throttle of the engine in response to the request to heat the after treatment device.

6. The engine method of claim 5 , where the central throttle is closed to a position where net flow across the intake poppet valve is negative and from the cylinder to an intake manifold during the cycle of the engine.

7. The engine method of claim 1 , further comprising combusting fuel in one or more cylinders during the cycle of the cylinder.

8. An engine system, comprising:
a diesel engine including a cylinder included in a first group of cylinders, a second group of cylinders, a central throttle, and an exhaust after treatment device, the cylinder including at an intake poppet valve and a decompression actuator to lift the intake poppet valve;
a controller including executable instructions stored in non-transitory memory that cause the controller to deactivate the cylinder and other cylinders included in the first group of cylinders while operating cylinders in the second group of cylinders in response to a request to heat the exhaust after treatment device, and additional instructions to hold the intake poppet valve open during an entire cycle of the diesel engine in response to the request to heat the exhaust gas after treatment device.

9. The engine system of claim 8 , further comprising:
a central throttle, a port throttle for the cylinder, and a port throttle for each of the other cylinders included in the first group of cylinders.

10. The engine system of claim 9 , further comprising additional instructions that cause the controller to open the port throttle for the cylinder during at least a portion of an exhaust stroke of the cylinder and to close the port throttle during at least a portion of an expansion stroke.

11. The engine system of claim 10 , further comprising additional instructions that cause the controller to fully open the central throttle while the request to heat the engine exhaust after treatment system is asserted.

12. The engine system of claim 8 , where the intake poppet valve is held open via the decompression actuator.

13. The engine system of claim 8 , further comprising additional instructions increase fuel flow to cylinders in the second group of cylinders in response to the request to heat the engine after treatment system.

14. An engine operating method, comprising:
opening a central throttle of an engine and holding closed a port throttle of a cylinder of the engine during at least a portion of an expansion stroke of the cylinder in response to a request to heat an engine exhaust gas after treatment system, an intake stroke of the cylinder occurring during a cycle of the engine; and
holding open the port throttle during at least part of an exhaust stroke of the cylinder, the exhaust stroke of the cylinder occurring during the cycle of the engine.

15. The engine method of claim 14 , further comprising deactivating the cylinder in response to the request to heat the engine exhaust gas after treatment system.

16. The engine method of claim 14 , further comprising increasing fuel injected to a second cylinder in response to the request to heat the engine exhaust.

17. The engine method of claim 14 , further comprising at least partially closing vanes of a turbocharger turbine in response to the request to heat the engine exhaust gas after treatment system.

18. The engine method of claim 14 , further comprising holding open an intake valve of the cylinder and adjusting lift of the intake valve to follow at least a portion of a trajectory of base valve lift during the entire cycle of the engine.

19. The engine method of claim 18 , further comprising opening and closing an exhaust valve of the cylinder during the cycle of the engine.

Assignees

• Ford Global Tech Llc

Inventors

• Kurtz Eric Matthew
• Martz Jason Brian

Classifications

• F02D41/38

  of the high pressure type · CPC title

• F01L2013/111

  Camshafts position or phase · CPC title

• F02D41/0002

  Controlling intake air · CPC title

• F02D41/0087

  Selective cylinder activation, i.e. partial cylinder operation (deceleration cut-off F02D41/123) · CPC title

• F02D13/0226

  changing valve lift or valve lift and timing · CPC title