FR2804174A1 - System to aid in the regeneration of particulates in the particulate filter in the exhaust system of a Diesel automotive engine - Google Patents

Abstract

The engine (1) has a unit (17) for controlling the function of different organs, these organs adapted for triggering a regeneration phase of the exhaust particulate filter by combustion of the particles trapped in it, and shutting a multiple fuel injection phase in the cylinders during the expansion phase. The control unit is adapted to be connected to an inlet unit for a request of forced triggering of a regeneration phase, by an operator, the control unit is also adapted for controlling the functioning of the engine and its associated organs, along a proper control strategy to trigger the regeneration of the filter.

Description

The present invention relates to a system for assisting the regeneration of a particulate filter integrated in an exhaust line of a diesel engine of a motor vehicle.

We know that the reduction of polluting emissions linked to the operation of motor vehicle engines and in particular diesel engines is a permanent concern of manufacturers.

Various systems have already been developed in the state of the art to reduce the level of these polluting emissions in particular by using a particle filter integrated in the exhaust line.

However, the management of its operation and in particular the management of its regeneration still generates difficulties.

The object of the invention is therefore to solve them.

To this end, the subject of the invention is a system for assisting the regeneration of a particulate filter integrated in an exhaust line of a diesel engine of a motor vehicle, characterized in that the engine is associated with different components, including - means for admitting air into the engine, - means for recycling exhaust gas from the engine at the inlet to it, - a turbocharger, - an oxidation catalyst placed upstream the particulate filter in the exhaust line; - a common fuel supply system for the engine cylinders, comprising electrically controlled injectors, associated with these cylinders, - means for adding to the fuel an additive intended to be deposited on the particle filter to lower the combustion temperature of the particles trapped therein, - means for acquiring information relating to different operating parameters of the engine and of the members associated with it, and - means for controlling the operation of the means intake, recycling means, turbocharger and / or supply system to control engine operation, these means being further adapted to trigger a regeneration phase of the particulate filter by combustion of the particles trapped in it ci by initiating a phase of multiple fuel injections into the engine cylinders during their expansion phase, and in that the means are adapted to be connected to means for input of a request for forced triggering of a regeneration phase of the particle filter, by an operator, the control means then being adapted to control the operation of the engine and of the organs associated with it according to a piloting strategy capable of triggering the regeneration of the filter.

The invention will be better understood on reading the description which follows, given solely by way of example and made with reference to the appended drawing which represents a block diagram illustrating a diesel engine of motor vehicle, and the various organs associated with it; This figure shows a motor vehicle diesel engine which is designated by the general reference 1.

This diesel engine is associated with air intake means at the inlet thereof, which are designated by the general reference 2.

At the output, this engine is associated with an exhaust line which is designated by the general reference 3.

Means for recycling the exhaust gas from the engine at the inlet thereof are also provided and are designated by the general reference 4. These means are then interposed, for example between the engine outlet and the intake means 2 of in this one.

The exhaust line can also be associated with a pressurized turbocharger designated by the general reference 5 and more particularly with the turbine portion thereof, in a conventional manner.

Finally, the exhaust line comprises an oxidation catalyst designated by the general reference 6, disposed upstream of a particle filter designated by the general reference 7, disposed in the exhaust line.

The engine is also associated with a common fuel supply system for the cylinders thereof. This system is designated by the general reference 8 in this figure and comprises, for example, electrically controlled injectors associated with these cylinders. In the embodiment shown, the engine is a four-cylinder engine and therefore comprises four electrically controlled injectors, respectively 9, 10, 11 and 12.

These different injectors are associated with a common fuel supply rail designated by the general reference 13 and connected to fuel supply means designated by the general reference 14, including for example a high pressure pump.

These supply means are connected to a fuel tank designated by the general reference 15 and to means for adding to this fuel an additive intended to be deposited on the particle filter to lower the combustion temperature of the particles. trapped in it.

In fact, this additive can for example be contained in an auxiliary tank designated by the general reference 16 associated with the fuel tank 15, to allow the injection of a certain quantity of this additive into the fuel.

Finally, this engine and the various members which have just been described are also associated with means for controlling their operation designated by the general reference 17 in this figure, comprising for example any suitable computer 18 associated with storage means for 'information 19, and connected as input to different means for acquiring information relating to different operating parameters of this engine and of these members, this calculator then being adapted to control the operation of the intake means, recycling, of the turbocharger and / or of the fuel system to control the operation of the engine and in particular the torque generated by it as a function of the driving conditions of the vehicle in a conventional manner.

Thus, for example, this computer is connected to a differential pressure sensor 20 at the terminals of the catalyst and of the particle filter, respectively 6 and 7, to temperature sensors 21, 22 and 23, respectively upstream of the catalyst. , between this catalyst and the particulate filter and downstream of this particulate filter in the exhaust line. The computer can also receive information on the oxygen content of the exhaust gases from a Lambda probe a, designated by the general reference 24 in this figure, integrated in the exhaust line.

At the outlet, this computer is suitable for controlling the air intake means, the exhaust gas recycling means, the pressurized turbocom, the means for adding the additive to the fuel, the means for supplying fuel from the common rail and the various injectors associated with the engine cylinders.

In particular, this computer is adapted to trigger a regeneration phase of the particle filter by combustion of the particles trapped in it by initiating a phase of multiple injections of fuel into the engine cylinders during their expansion phase.

The particles emitted by the engine during its operation are in fact trapped in the particle filter. It should then be regenerated regularly by combustion of these particles.

The control means 17 and more particularly the computer 18 are also adapted to be connected to means 25 for inputting a request for forced triggering of a regeneration phase of the particle filter by an operator.

These input means can, for example, be integrated into the vehicle or into a tool external to this vehicle adapted to be connected to the control means 17 by complementary connectors for example.

This phase of forced regeneration of the particulate filter can then be triggered when the vehicle passes through a garage for any maintenance operation.

During this forced regeneration phase, the control means 17 control the operation of the engine and of the members associated with it according to a strategy capable of causing the filter to regenerate in a conventional manner.

The control means 17 can then in this case be associated with different means of acquiring information relating to specific security conditions of the vehicle before triggering this forced regeneration of the filter. Thus, for example, the control means can be brought to verify that the vehicle gearbox is in neutral, that the parking brake of the latter is properly applied, etc.

Of course, other security conditions can be checked.

Claims (4)

<U> CLAIMS </U> 1. A system for assisting the regeneration of a particulate filter integrated into an exhaust line of a diesel engine of a motor vehicle, characterized in that the engine (1) is associated with different members, among which - means (2) for admitting air into the engine, - means (4) for recycling exhaust gases from the engine at the inlet thereof, - a turbocharger (5), - an oxidation catalyst ( 6) disposed upstream of the particulate filter (7) in the exhaust line, - a system (8) for the common supply of fuel to the engine cylinders, comprising electrically controlled injectors (9,10,11,12 ), associated with these cylinders, - means (16) for adding to the fuel an additive intended to be deposited on the particle filter (7) to lower the combustion temperature of the particles trapped therein, - means (20,21,22,23,24) of acquiring information relating to different operating parameters ment of the engine and of the members associated with it, and - means (17) for controlling the operation of the intake means, recycling means, of the turbocharger and / or of the supply system for controlling the operation of the engine , these means being further adapted to trigger a regeneration phase of the particle filter by combustion of the particles trapped therein by initiating a phase of multiple injections of fuel into the engine cylinders during their expansion phase, and in this that the control means (17) are adapted to be connected to means (25) for inputting a request for forced initiation of a regeneration phase of the particle filter (7), by an operator, the means of control (17) then being adapted to control the operation of the engine and of the members associated with it according to a control strategy capable of triggering the regeneration of the filter. 2. System according to claim 1, characterized in that the means (25) for inputting the request are integrated into the vehicle. 3. System according to claim 1, characterized in that the means (25) for inputting the request are integrated into a tool external to the vehicle and adapted to be connected to the control means (17) by complementary connectors. 4. System according to any one of the preceding claims, characterized in that the control means (17) are associated with means for acquiring information relating to vehicle safety conditions before triggering the forced regeneration phase .