Controller for variable valve mechanism

Patent metadata

Field	Value
Publication number	US-9500141-B2
Application number	US-201314126159-A
Country	US
Kind code	B2
Filing date	Apr 2, 2013
Priority date	Apr 2, 2013
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

An internal combustion engine includes a plurality of cylinders, intake valves ( 31 ) provided respectively in the cylinders, and a variable valve mechanism ( 600 ) for changing a valve characteristic of the intake valves ( 31 ). A motor ( 210 ) drives the variable valve mechanism ( 600 ). A motor controller ( 150 ) controls the motor ( 210 ). The internal combustion engine can be operated in a cylinder deactivation mode for retaining the intake valves ( 31 ) of some of the cylinders in a valve closing state. When the internal combustion engine returns from the cylinder deactivation mode, the motor controller ( 150 ) executes overlap adjustment processing for controlling the valve characteristic such that valve opening periods of the intake valves ( 31 ) are not overlapped between the cylinders.

First claim

The invention claimed is:

1. A controller for a variable valve mechanism applied to an internal combustion engine including a plurality of cylinders, intake valves provided respectively in the cylinders, and a variable valve mechanism for changing a valve characteristic of the intake valves, wherein the internal combustion engine is capable of switching an operation mode between a cylinder deactivation mode for retaining the intake valves of some of the cylinders in a valve closing state and an all-cylinder operation mode for performing opening and closing actions of the intake valves of all the cylinders, the controller comprising:
a control section for controlling the valve characteristic, wherein
the control section is capable of setting, as the valve characteristic at the time of executing the all-cylinder operation mode, a valve characteristic with which an overlap is generated in valve opening periods of the intake valves between the cylinders, and
when the internal combustion engine returns from the cylinder deactivation mode, the control section is configured to execute overlap adjustment processing for controlling the valve characteristic such that an overlap amount in the valve opening periods of the intake valves between the cylinders becomes smaller than an overlap amount set in the all-cylinder operation mode.

2. The controller for a variable valve mechanism according to claim 1 , wherein the valve characteristic when the overlap adjustment processing is executed is a valve characteristic with which the valve opening periods of the intake valves are not overlapped between the cylinders.

3. The controller for a variable valve mechanism according to claim 1 , wherein the control section is configured to complete execution of the overlap adjustment processing after air-fuel mixture is combusted in the cylinders that have returned from the cylinder deactivation mode.

4. The controller for a variable valve mechanism according to claim 1 , wherein
the variable valve mechanism is a multistage variable valve mechanism for changing the valve characteristic in multiple stages by selecting a valve characteristic from a plurality of valve characteristics set in advance, and
the valve characteristic at the time of executing the overlap adjustment processing is set as one of the plurality of valve characteristics.

5. The controller for a variable valve mechanism according to claim 4 , wherein
the multistage variable valve mechanism includes a variable mechanism unit for changing the valve characteristic of the intake valves, a control shaft for activating the variable mechanism unit, a cam for moving the control shaft in the axial direction, and an electric motor for turning the cam, and
a cam surface of the cam has a section in which an axial displacement amount of the control shaft is changed, and a plurality of sections in which the displacement amount is constant.

6. The controller for a variable valve mechanism according to claim 1 , wherein the internal combustion engine includes a forced induction device for supercharging intake air by utilizing exhaust gas.

7. The controller for a variable valve mechanism according to claim 1 , wherein the internal combustion engine includes a return passage for returning some of the exhaust gas to the intake air.

Assignees

• Hioka Eiichi
• Toyota Motor Co Ltd

Inventors

• Hioka Eiichi

Classifications

• F02D13/06

  Cutting-out cylinders · CPC title

• F02D13/023

  the change of valve timing is caused by the change in valve lift, i.e. both valve lift and timing are functionally related · CPC title

• F01L2013/001

  Deactivating cylinders · CPC title

• F01L13/0005

  Deactivating valves · CPC title

• F01L1/2405

  by means of a hydraulic adjusting device located between the cylinder head and rocker arm · CPC title