EXHAUST GAS PURIFICATION SYSTEM FOR INTERNAL COMBUSTION ENGINE

• US 20200132036A1
• Filed: 09/17/2019
• Published: 04/30/2020
• Est. Priority Date: 10/30/2018
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: ASHIZAWA, Takeshi
• Granted Patent: US 10,823,026 B2
• Time in Patent Office: Days
• CPC Class Codes: F01N 2430/06 by varying fuel-air ratio, e.g. by enriching fuel-air mixture
• CPC Class Codes: F01N 2900/1602 Temperature of exhaust gas apparatus
• CPC Class Codes: F01N 3/10 by thermal or catalytic conversion of noxious components of exhaust by using other chemical processes, chemical aspects of catalytic conversion, e.g. using specified catalysts, B01D53/34
• CPC Class Codes: F01N 3/101 Three-way catalysts
• CPC Class Codes: F01N 3/20 specially adapted for catalytic conversion F01N3/22 takes precedence; Methods of operation or control of catalytic converters
• CPC Class Codes: F02N 99/004 Generation of the ignition spark
• CPC Class Codes: F02P 5/045 combined with electronic control of other engine functions, e.g. fuel injection in general F02D37/02
• CPC Class Codes: F02P 5/15 Digital data processing
• CPC Class Codes: F02P 5/1506 with particular means during starting
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

At the start of the engine, when the temperature of the catalyst is less than the activation temperature, control for activating the catalyst (i.e., activation control) is performed. In the activation control, the first and second discharge actions of the ignition apparatuses are controlled. The first discharge action is performed to ignite the mixed gas in the cylinder. The second discharge action is performed to generate ozone. The first discharge action is performed immediately after the start of the cranking. The first discharge action is performed in the crank angle section at the retard side rather than the compression TDC. The first discharge action is performed in every cylinder. The second discharge action is performed before the start of the cranking. The second discharge action is performed in the other cylinder except for the initial combustion cylinder.

Claims

1. An exhaust gas purification system for internal combustion engine, comprising:

an internal combustion engine including multiple cylinders;

ignition apparatuses which are provided to each of the multiple cylinders;

a catalyst which is configured to purify exhaust gas of the internal combustion engine; and

a controller which is configured to control discharge actions of the ignition apparatuses for each cylinder,

wherein the discharge actions include a first discharge action for igniting mixed gas in the cylinder and a second discharge action for generating ozone,

wherein the controller is further configured to execute activation control of the catalyst when the internal combustion engine is started,

wherein, in the activation control, the controller is configured to;

identify an initial combustion cylinder at which the mixed gas is initially ignited among all cylinders;

control the ignition apparatuses such that the first discharge action is performed in the initial combustion cylinder; and

before the first discharge action is performed in the initial combustion cylinder, control the initiation apparatuses such that the second discharge action is performed only in other cylinder excluding the initial combustion cylinder.

2. The exhaust gas purification system according to claim 1, further comprising injectors which are provided to each of the multiple cylinders,

wherein the controller is further configured to control injection actions of the injectors for each cylinder,

wherein, in the activation control, the controller is configured to control the injectors such that fuel is supplied only to the initial combustion cylinder before the first discharge action is performed in the initial combustion cylinder.

3. The exhaust gas purification system according to claim 1, further comprising injectors which are provided to each of the multiple cylinders,

wherein the controller is further configured to control injection actions of the injectors for each cylinder,

wherein, in the activation control, the controller is configured to:

after the first discharge action is performed in the initial combustion cylinder, control the ignition apparatuses such that the first discharge action is performed in every cylinder in a crank angle section at a retard side rather than compression top dead center; and

after the first discharge action is performed in the initial combustion cylinder, control the injectors such that fuel is supplied to every cylinder.