Control device for internal combustion engine

Patent metadata

Field	Value
Publication number	US-9347384-B2
Application number	US-201214400067-A
Country	US
Kind code	B2
Filing date	May 14, 2012
Priority date	May 14, 2012
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A control device for an internal combustion engine is provided with: a variable valve driving mechanism capable of changing a working angle of an intake valve while keeping a maximum magnitude of lift and opening timing constant; a reduction catalyst which absorbs nitrogen oxide in exhaust during lean combustion and reduces the nitrogen oxide absorbed during rich combustion; and a control unit changing, according to a load on the internal combustion engine, an amount of advance of closing of the intake valve at the time of switching to rich combustion.

First claim

The invention claimed is:

1. A control device for an internal combustion engine comprising:
a variable valve driving mechanism configured to change a working angle of an intake valve while keeping a maximum magnitude of lift and opening timing constant;
a reduction catalyst which absorbs nitrogen oxide in exhaust during lean combustion and reduces the nitrogen oxide absorbed during rich combustion; and
a control unit changing, according to a load on the internal combustion engine, an amount of advance of a timing of closing of the intake valve at a time of switching to rich combustion.

2. The control device according to claim 1 , wherein the control unit increases the amount of advance as the load on the internal combustion engine decreases.

3. The control device according to claim 1 , wherein the control unit advances the timing of the closing of the intake valve and then increases a fuel injection amount at the time of switching to rich combustion.

4. The control device according to claim 1 , wherein:
the variable valve driving mechanism is configured to change a phase of the intake valve in addition to changing of the working angle of the intake valve; and
the variable valve driving mechanism maximizes lift of the intake valve at a crank angle at which a flow rate of intake air becomes a maximum.

5. The control device according to claim 1 , wherein:
the control device is a control device for an internal combustion engine having two exhaust ports or more per cylinder; and
the control device opens one of the two exhaust ports or more located upstream in a swirl flow on an intake stroke during a low-load operation of the internal combustion engine.

Assignees

• Takada Noriyuki
• Ishiyama Shinobu
• Ogawa Takashi
• Toyota Motor Co Ltd

Inventors

• Takada Noriyuki
• Ishiyama Shinobu
• Ogawa Takashi

Classifications

• F01L1/267

  with means for varying the timing or the lift of the valves · CPC title

• F02D13/0257

  Independent control of two or more intake or exhaust valves respectively, i.e. one of two intake valves remains closed or is opened partially while the other is fully opened · CPC title

• F01N2430/06

  by varying fuel-air ratio, e.g. by enriching fuel-air mixture · CPC title

• F01N2430/10

  by modifying inlet or exhaust valve timing · CPC title

• F02D13/0226 Primary

  changing valve lift or valve lift and timing · CPC title