Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
  • F01N13/008—Mounting or arrangement of exhaust sensors in or on exhaust apparatus
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
  • F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N1/00—Silencing apparatus characterised by method of silencing
  • F01N1/02—Silencing apparatus characterised by method of silencing by using resonance
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
  • F01N11/007—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2230/00—Combination of silencers and other devices
  • F01N2230/02—Exhaust filters
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2240/00—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being
  • F01N2240/20—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being a flow director or deflector
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2410/00—By-passing, at least partially, exhaust from inlet to outlet of apparatus, to atmosphere or to other device
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2470/00—Structure or shape of gas passages, pipes or tubes
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
  • F01N2550/04—Filtering activity of particulate filters
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
  • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
  • F01N2560/025—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor for measuring or detecting O2, e.g. lambda sensors
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
  • F01N2560/06—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being a temperature sensor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
  • F01N2560/07—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas flow rate or velocity meter or sensor, intake flow meters only when exclusively used to determine exhaust gas parameters
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
  • F01N2560/08—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being a pressure sensor
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/40—Engine management systems

Definitions

• the invention relates to a device for the diagnosis of a particulate filter attached to a main exhaust line of an internal combustion engine, a diagnostic device of the type comprising, downstream of the first particle filter, a detection filter. and means for measuring an output parameter of the detection filter.
• the most commonly used particulate filters are composed of a set of channels with filtering walls and plugged alternately at the inlet or the outlet ( Figure 1).
• the exhaust gases enter one channel and exit through another after passing through at least one filter wall.
• filters made of silicon carbide (SiC) the channels are grouped into segments interconnected by a seal that compensates for the significant expansion of silicon carbide during thermal transients.
• Particle filters now installed on almost all motor vehicles in Europe are highly efficient and can limit particle emissions to less than 5 mg / km traveled, the maximum level allowed by the Euro 5 standard which will come into effect in 2010 and measured following the standard NEUDC driving cycle.
• Standards for other diesel applications or more generally with thermal engines (trucks, agricultural machinery, constructions) in Europe as well as in other countries like the United States and Japan impose similar limits.
• particulate filters are known to be robust and suitably perform their function throughout the life of the vehicles on which they are installed, some filters may fail, for example because of a manufacturing defect, or they may fail. following severe operating conditions for example.
• the most well-known failures result in cracking of a filter wall, a seal connecting several segments and / or a plug closing a or more channels. These failures result in a particle emission higher than the threshold tolerated by the legislation.
• the current OBD (On Board Diagnostic) standard requires the establishment of means for detecting a component failure (in particular the particulate filter) that could lead to pollutant emissions exceeding the threshold set by legislation. . These detection means must send a visible signal to the driver of the vehicle to signal the need to control pollutant emissions.
• Resistive sensors a metal plate positioned in the flow coming out of the particle filter increases its resistance when particles stick to it.
• the soot deposition mechanisms on the resistive element are very complex; dependent on parameters that are difficult to control.
• low-intensity electrical signals require expensive processing electronics.
• Electric discharge sensors two electrodes are arranged in the flow of gases leaving the particle filter and, when a predefined high voltage is applied between these electrodes, an electric discharge occurs if the quantity of particles in the gas flow is greater than a threshold value.
• Optical sensors an optical signal passing through the flow of gases leaving the particle filter makes it possible to determine the quantity of particles present in the stream. These sensors, however, are difficult to maintain in good operating condition in a difficult environment such as exhaust.
• Another technique envisaged in document Dl consists in putting a detection filter downstream of the particulate filter and detecting the pressure difference between the input and the output of the detection filter.
• a pressure difference close to zero means that the detection filter does not stop particles, that is to say that the particles present in the exhaust gas leaving the engine have been properly filtered in the particulate filter.
• an increasing pressure difference means that the detection filter is fouled with particles that are not filtered by the particulate filter, ie the particulate filter fails.
• the main disadvantage of the solution proposed in D1 is that, in normal operation, the detection filter generates a significant counter-pressure in the exhaust duct, especially at the points of operation of the engine where the gas flow is important.
• WO 03/091553 discloses a defect detection device for a particulate filter.
• the device is in the form of a chamber installed in the exhaust duct of an engine, downstream of the particulate filter.
• the chamber comprises a filter wall, facing the flow of exhaust gas, and a gas outlet port in the opposite wall.
• the device uses two oxygen sensors, one placed in the chamber and the other in the conduit.
• the invention proposes a new diagnostic device, not having the disadvantages of the prior devices described above.
• the invention proposes a device for diagnosing a particulate filter fixed on a main exhaust line of an internal combustion engine, the diagnostic device comprising, downstream of the first particulate filter, a filter of detection and means for measuring an output parameter of the detection filter representative of an operating state of the particulate filter.
• the detection filter is traversed by a first portion of the gases from the particulate filter, a second part of the gases from the particulate filter along the main exhaust line.
• the portion of the gas passing through the detection filter is preferably small relative to the total amount of gas exiting the particulate filter, for example between 0.1 and 70%.
• the quantity of gas passing through the detection filter is limited to the amount necessary and sufficient to allow the measurement of the output parameter of the filter. detection with the desired accuracy.
• the portion of the gas passing through the detection filter is preferably limited to 0.1 to 15% of the total quantity of gas leaving the particulate filter, more preferably 0.1 to 10%, and even 0.1 to 5%. With a fraction of the exhaust gas as low, it is possible to use a small detection filter. This makes it possible to limit the bulk while allowing accurate measurement.
• the detection filter is installed in a secondary exhaust line which divides the flow of the main line downstream of the particle filter and extends outside the main line (at least in part).
• the secondary line comprises a gas inlet connected to the main exhaust line downstream of the particulate filter.
• the use of a secondary line distinct from the main line (and external to it) is particularly advantageous when working on the basis of temperature variations generated by the clogging of the detection filter, because this avoids a warming by the main line.
• the secondary line may of course include an inlet section placed in the main line to deflect a portion of the gases, and, where appropriate, an outlet section may be positioned in the main line.
• the means for measuring an output parameter of the detection filter then comprises a sensor placed in the secondary line portion out of the line. main, which can be used alone or in combination with an upstream sensor as discussed below.
• the detection filter can be placed in the secondary line (out of the main line) or in the input section of the secondary line, so in the main line. This latter configuration is advantageous for regenerating the detection filter via heating caused by the regeneration of the particulate filter.
• the measuring means can be:
• a temperature, flow rate, flow velocity or oxygen concentration sensor of the gases positioned at the output of the detection filter, or
• a differential measuring means able to establish a difference (gradient) between the input and the output of the detection filter. It may be for example a means for measuring differential pressure or differential temperature, comprising a first pressure sensor, respectively a temperature sensor, upstream of the detection filter, a second pressure sensor, respectively a temperature sensor, downstream of the detection filter and a comparator able to determine a difference in pressure, respectively temperature, between the input and the output (upstream / downstream difference) of the detection filter.
• the diagnostic device may also comprise an alerting means for producing an alert signal if a profile of the output parameter of the detection filter is different from a reference profile.
• the device according to the invention is particularly useful for equipping motor vehicles, such as cars, trucks, tractors, etc. But it can also be used more generally for the diagnosis of any particulate filter associated with a heat engine, such as for example engines on fixed installations, boats, construction equipment, etc.
• Preferred embodiments of the present invention are set forth in dependent claims 2 to 17.
• the present invention relates to a method of diagnosing a particulate filter according to claim 18.
• Preferred embodiments are set forth in dependent claims 19 to 22.
• FIG. 1 is a block diagram of a diagnostic device according to one embodiment of the invention.
• FIGS. 2 to 5, 11 and 12 show variants of the device of FIG. 1;
• Figure 6 is a graph illustrating the speed of the exhaust gas according to the operating state of the particulate filter
• FIGS. 7, 8 and 10 show illustrations of the signals measured by the sensors to be used by the electronic controller of the motor
• Figure 9 illustrates the principle of calibration and detection of the present device.
• FIG. 1 a known particulate filter comprising an inlet 11 for connection to an exhaust outlet of a heat engine.
• An outlet 12 of the particulate filter 10 is connected to a main exhaust line 13 in which the exhaust gas has a total flow rate Qt when the engine is operating normally.
• the diagnostic device comprises, downstream of the particle filter 10, a detection filter 14 and a measurement means 15.
• the detection filter 14 is positioned so as to receive only a part of the flow of the gases leaving the particle filter, and the detection means 15 is preferably fixed at the output of the detection filter (downstream, after this).
• the detection filter preferably has filtering properties similar to those of a particulate filter.
• the most widely used particle filters today are those of silicon carbide or cordierite but with different filter properties such as porosity, pore size and the number of channels per flow passage section.
• the detection filter employed is designed to allow a low pressure drop when the detection filter is not loaded with soot and then clog quickly even with very low levels of soot emissions.
• Other filters such as metal foams or woven metal sheets can be used when they have such a filtering behavior.
• the detection filter 14 is placed in a bypass duct or secondary exhaust line 16.
• the secondary line is dimensioned (section, shape, etc.) so that only 0.1 to 70% of the total of the gases
• the exhaust system is diverted to the secondary line and the detection filter.
• the section is limited so that only 0.1 to 15%, more preferably 0.1 to 10% or 0.1 to 5%, of the total of the exhaust gases is drifted to the secondary line. and the detection filter, to limit at best the consequences on the operation of the engine of a fouling of the detection filter 14 during a failure of the particulate filter 10.
• An inlet 17 of the secondary line is connected to the main line 13 downstream of the particle filter 10 so that said inlet 17 is subjected to the total pressure Ptotal gases.
• an output of the secondary line is connected to the main exhaust line so that, at the outlet of the secondary line, the gases are only subjected to the static pressure.
• An output of the secondary line is made such that, at the output of the secondary line, the gases are subjected to a pressure less than or equal to the static pressure Pstatic.
• the output of the secondary line is left in the open air, the gases are thus subjected to the output at the only atmospheric pressure (less than the static pressure) and the pressure difference between the inlet and the outlet of the secondary line is greater than the dynamic pressure.
• the flow of gases in the secondary line is a function notably of:
• the shape, the dimensions, and the connection on the main line of the secondary line are therefore dimensioned so that the secondary flow rate of the gases is sufficient to allow a detection of a parameter of the gases by the detection means 14. If necessary, several solutions can be considered to increase the secondary flow.
• the secondary exhaust line thus realizes a deflection of a portion of the exhaust gas and constitutes a distinct line of the main duct extending out of it.
• the main line For its connection to the main line, it may simply be connected to the main conduit, or include an inlet section (or primer) within the main line to facilitate gas deflection.
• the inlet section is preferably substantially parallel to the gas flow.
• the restriction can be a grid (19a) placed around the inlet section 17 of the secondary line or a simple restriction (19b) or any other means that can increase the pressure drop in the main exhaust line behind the section d entry 17.
• a main line comprising in series a particle filter 10 and an additional element (such as a silencer 20 or a resonator), to position the input of the secondary line between the output of the particle filter 10 and the inlet of the additional element.
• the secondary line is thus in derivation with respect to the main line.
• the outlet 18 of the secondary line can be left open (Figure 1), so that the exhaust gases are discharged in the open air, as well as the gases flowing in the main line.
• the outlet 18 can also be connected to the main line downstream of the inlet 17 (FIGS. 2, 3).
• the outlet 18 can still be connected to the main line downstream of the additional element if there is one (FIG. 4).
• It can also be connected to any point of the exhaust line or engine air intake (not shown) may have a pressure differential sufficient to ensure a flow derived from a suitable flow.
• the secondary line 16 can be installed inside a muffler 20 to save space (FIG. 5).
• the detection filter 14 has filtering properties similar to those of a particulate filter:
• the detection filter passes all the particles passed through the particulate filter (i.e. the smallest particles or soot and in a very small residual amount); the detection filter is thus quasi-transparent for the flow of gas that passes through it,
• the detection filter blocks all particles that the particulate filter should have filtered if it had functioned properly. As the detection filter has detection capabilities (in terms of volume and number of particles that it is able to absorb), the detection filter gradually clogs up to almost no longer allow the gas to pass.
• the amount of soot leaking from the main filter can be determined by measuring the gas temperature gradient between the inlet and the outlet of the detection filter. Indeed, when the flow rate of the deflected gases towards the detection filter decreases because of the clogging of the latter, the temperature loss through the detection filter will tend to increase as shown in FIG. 10. While without soot leakage of the main filter, the temperature gradient between the input and the output of the detection filter remains constant. The increase in the temperature gradient is directly related to the level of soot leakage. It is therefore sufficient to characterize the temperature gradient through the detection filter over time as a function of the deviated gas flow and the level of soot emissions, to store these reference data in the engine control unit for the engine. then use them during operation of the vehicle or the engine to give the warning signal as soon as a temperature gradient corresponding to the maximum soot level tolerated is reached or exceeded.
• the detection filter can be made according to the same principle and with the same materials as the particulate filter. But any other type of filter can be used, as long as it has the above properties.
• gas flow parameters such as temperature, pressure, flow rate, flow rate, oxygen concentration, etc. placed at the output and / or at the input of the detection filter. It is therefore possible to use as a measuring means at the output of the detection filter a single sensor (FIGS. 1, 2, 4, 5) such as a temperature, pressure, flowmeter, anemometer, probe or oxygen, etc. All these sensors are widely known, they have the advantage of being robust, efficient even in a difficult environment such as exhaust and do not require complex control electronics.
• a differential measuring means for example pressure or differential temperature (see Figure 3), comprising a first pressure sensor (or temperature) 24 upstream of the detection filter 14, a second pressure sensor (or temperature sensor) 25 downstream of the detection filter and a comparator 26 adapted to determine a pressure difference (or temperature) between the upstream and downstream of the detection filter.
• a differential measuring means for example pressure or differential temperature (see Figure 3), comprising a first pressure sensor (or temperature) 24 upstream of the detection filter 14, a second pressure sensor (or temperature sensor) 25 downstream of the detection filter and a comparator 26 adapted to determine a pressure difference (or temperature) between the upstream and downstream of the detection filter.
• the particulate filter is regenerated regularly when the engine is running.
• the temperature of the exhaust gas is raised significantly to burn the soot absorbed by the particulate filter.
• the detection filter may be automatically regenerated each time the particulate filter is regenerated.
• the particulate filter is regenerated from time to time even if it fails.
• the detection filter must be dimensioned to clog quickly in case of failure of the particulate filter, so that it can be detected before the regeneration of the particulate filter. In such a case, a small detection filter is used.
• the present diagnostic device advantageously also comprises an alert means (not shown), for monitoring the variations in time of the parameter measured by the measuring means and producing an alert signal if the profile of the measured signal is different from a reference profile.
• the alerting means is a comparator, which compares the amplitude of the output parameter with a reference threshold and produces the alert signal when the magnitude of the output parameter is below the reference threshold.
• the alert means comprises a memory and a comparator.
• the memory is stored a reference profile corresponding to the evolution of the detected parameter as a function of time in the case of normal operation of the particulate filter.
• the reference profile is for example obtained by testing the vehicle in which a diagnostic device is installed, before it is put on the market.
• the comparator continuously compares the signal supplied by the measuring means with the reference profile, and provides the alert signal when the measured signal deviates more than X% from the reference profile.
• X is a percentage whose value is to be adjusted according to properties desired for the diagnostic device (speed of detection of a particle filter failure, guarantee that an alert corresponds to a failure of the particulate filter, etc.). ).

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Analytical Chemistry (AREA)
• Processes For Solid Components From Exhaust (AREA)
• Exhaust Gas After Treatment (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=43446400

Family Applications (1)

Country Status (3)

Families Citing this family (21)

Family Cites Families (13)

• 2010
  • 2010-09-14 EP EP10754486.8A patent/EP3137744A1/de not_active Withdrawn
  • 2010-09-14 US US13/395,862 patent/US20130047841A1/en not_active Abandoned
  • 2010-09-14 WO PCT/EP2010/063455 patent/WO2011032933A1/fr active Application Filing

Also Published As

Similar Documents

Legal Events