Valve train with cylinder deactivation and compression release

Patent metadata

Field	Value
Publication number	US-11512653-B2
Application number	US-202117378996-A
Country	US
Kind code	B2
Filing date	Jul 19, 2021
Priority date	Dec 18, 2017
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

An internal combustion engine system includes an engine with a plurality of pistons housed in respective ones of a plurality of cylinders, an air intake system to provide air to the plurality of cylinders through respective ones of a plurality of intake valves, an exhaust system to release exhaust gas from the plurality of cylinders through respective one of a plurality of exhaust valves. A valve train is provided for cylinder deactivation of a first part of the plurality of cylinders and compression release braking on a second part of the plurality of cylinders.

First claim

What is claimed is:

1. A method, comprising:
operating an internal combustion engine system including an internal combustion engine with a plurality of cylinders that receive a charge flow for combustion of a fuel provided to at least a portion of the plurality of cylinders;
deactivating at least part of the plurality of cylinders in response to a cylinder deactivation condition; and
compression release braking the internal combustion engine in response to a braking condition by adjusting at least an exhaust valve opening and closing timing of cylinders involved in the compression release braking, wherein braking condition is distinct from the cylinder deactivation condition, wherein compression release braking the internal combustion engine includes increasing a braking amount by switching from a first compression release braking to a second compression release braking.

2. The method of claim 1 , wherein compression release braking the internal combustion engine includes adjusting both the exhaust valve opening and closing timing and an intake valve opening and closing timing of the cylinders involved in the compression release braking.

3. The method of claim 1 , wherein adjusting at least the exhaust valve opening and closing timing includes switching a valve lift profile of at least one exhaust valve from a nominal valve lift profile to a compression release lift profile.

4. The method of claim 3 , wherein braking the internal combustion engine further includes providing a two stroke compression release braking by switching a valve lift profile of at least one intake valve from a nominal valve lift profile to a compression release lift profile.

5. A method, comprising:
operating an internal combustion engine system including an internal combustion engine with a plurality of cylinders that receive a charge flow for combustion of a fuel provided to at least a portion of the plurality of cylinders;
deactivating at least part of the plurality of cylinders in response to a cylinder deactivation condition; and
in response to a braking condition, reducing the charge flow, adjusting at least an exhaust valve opening and closing timing of cylinders involved in compression release braking the internal combustion engine to provide four stroke compression release braking after reducing the charge flow, and increasing the charge flow to increase a braking amount while providing four stroke compression release braking, wherein braking condition is distinct from the cylinder deactivation condition.

6. The method of claim 5 , further comprising, after increasing the charge flow, reducing the charge flow while adjusting the intake valve opening and closing timing to provide two stroke compression release braking to further increase the braking amount.

7. The method of claim 6 , further comprising increasing the charge flow to further increase the braking amount while providing the two stroke compression release braking.

8. A system, comprising:
an internal combustion engine including a plurality of cylinders that receive a charge flow from an intake system and an exhaust system for receiving exhaust gas produced by combustion of a fuel provided to at least a portion of the plurality of cylinders;
a plurality of sensors operable to provide signals indicating operating conditions of the system;
a valve actuation mechanism configured to control an opening and closing timing of exhaust valves and intake valves associated with the plurality of cylinders; and

a controller connected to the plurality of sensors operable to interpret one or more signals from the plurality of sensors, wherein the controller, in response to a cylinder deactivation condition, is configured to control the valve actuation mechanism to deactivate part of the plurality of cylinders and, in response to a braking condition, provide a compression release braking by adjusting a timing of an exhaust valve opening and an exhaust valve closing of cylinders involved in the compression release braking, wherein the controller is configured to increase a braking amount by switching from a first compression release braking to a second compression release braking.

9. The system of claim 8 , wherein the controller is configured to adjust a timing of an intake valve opening and an intake valve closing of the cylinders involved in the compression release braking.

10. The system of claim 8 , wherein the intake system includes an intake throttle and the controller is configured to modulate the intake throttle in response to the braking condition.

11. A system, comprising:
an internal combustion engine including a plurality of cylinders that receive a charge flow from an intake system that includes an intake throttle and an exhaust system for receiving exhaust gas produced by combustion of a fuel provided to at least a portion of the plurality of cylinders;
a plurality of sensors operable to provide signals indicating operating conditions of the system;
a valve actuation mechanism configured to control an opening and closing timing of exhaust valves and intake valves associated with the plurality of cylinders; and
a controller connected to the plurality of sensors operable to interpret one or more signals from the plurality of sensors, wherein the controller, in response to a cylinder deactivation condition, is configured to control the valve actuation mechanism to deactivate part of the plurality of cylinders and, in response to a braking condition, provide a compression release braking by adjusting a timing of an exhaust valve opening and an exhaust valve closing of cylinders involved in the compression release braking, wherein the controller is configured to, in response to the braking condition, modulate the intake throttle to reduce the charge flow, adjust the exhaust valve opening and closing timing to provide four stroke compression release braking after reducing the charge flow, and increase the charge flow via the intake throttle to increase a braking amount while providing four stroke compression release braking.

12. An apparatus, comprising:
a controller for connection to a plurality of sensors configured to interpret signals from the plurality of sensors associated with operation of an internal combustion engine, wherein the controller is further configured to determine a cylinder deactivation condition from the signals of the plurality of sensors and provide a cylinder deactivation command to deactivate part of a plurality of cylinders of the internal combustion engine in response to the cylinder deactivation condition, and wherein the controller is further configured to determine a braking condition from the signals of the plurality of sensors and provide a compression release braking by adjusting a timing of an exhaust valve opening and an exhaust valve closing of cylinders involved in the compression release braking, wherein the controller is configured to increase a braking amount by switching from a first compression release braking to a second compression release braking.

13. The apparatus of claim 12 , wherein the controller is configured to adjust a timing of an intake valve opening and an intake valve closing of the cylinders involved in the compression release braking.

14. The apparatus of claim 13 , wherein the controller is configured to switch a cam lobe profile operating to open and close the exhaust valves and the intake valves of the cylinders involved in the compression release braking.

15. The apparatus of claim 12 , wherein the controller is configured to modulate an intake throttle that provides a charge flow to the internal combustion engine

Assignees

• Cummins Inc

Inventors

• Perfetto Anthony Kyle
• Shambhav Anshul
• Cecil Adam C
• Schultz Ryan Edward

Classifications

• F01L2820/01

  Absolute values · CPC title

• F02D13/0207

  changing valve lift or valve lift and timing · CPC title

• F01L2800/00

  Methods of operation using a variable valve timing mechanism · CPC title

• F01L2800/08

  Timing or lift different for valves of different cylinders · CPC title

• F01L13/065

  Compression release engine retarders of the "Jacobs Manufacturing" type · CPC title