Patent Application
20230177895
The present invention generally relates to internal combustion engine (or combustion engine) depollution techniques, and more specifically to a method for descaling a combustion engine by hydrogen injection, as well as a descaling station for its implementation.
The invention has applications, in particular, in maintaining internal combustion engines implemented in motor vehicles of all types, in the land vehicle field (personal and utility vehicles, road transport lorries, farming vehicles, military vehicles, site vehicles for public works or forestry works, etc.), but also in other fields, like marine or aeronautics, or also in generator combustion engines. The examples thus given are not limiting.
The clogging of internal combustion engines of motor vehicles is mainly due to current motor vehicle traffic conditions, namely, in particular:
Carbon residue from combustion (i.e. scale) is installed inside the engine, in particular in sensitive parts, such as:
The descaling of an internal combustion engine aims to fight against the accumulation in the engine of this carbon residue, or soot, which is responsible for them clogging over time. This residue weakens the abovementioned parts of the engine, and cause damaging effects on the engine's performance and on the emission of damaging matter or particles into the environment.
In the past, each use was able to count, in a certain measurement and with various pleasure, on the detergents contained in high-end fuel, even, on so-called “descaling” additives, to keep their engine clean.
For a few years, the descaling of an engine by hydrogen injection appeared and offers an effective and inexpensive alternative as regards the benefits which can be expected from it. This method consists of injecting hydrogen inside the engine of a vehicle in the inlet of the engine, while making it operate a low revs, with the vehicle stopped, for a duration of between thirty minutes and around one and a half hours. This has the effect of removing the soot deposits inside the engine, this soot thus being burnt and/or released into the exhaust. The vehicle, once cleared from combustion residue which pollutes its engine, returns substantially all of the performance given by the manufacturer for a vehicle equipped with a new engine, and in particular decreases its fuel consumption.
Document FR3041997A discloses a descaling system comprising a control means arranged to control an opening or a closing of the EGR valve of the engine according to parameters of the injected cleaning fluid, in order to make the cleaning fluid circulate better in the top part of the engine, in the inlet circuit, and in the gas recirculation circuit. This controlling of the EGR valve which opens and closes during treatment allows it to be cleaned well.
Document FR3064025 discloses a cleaning installation comprising a diagnostic means adapted to determine a clogging rate of a motorisation system comprising an internal combustion engine according to intrinsic parameters of said motorisation system, and a means for controlling a device for injecting a cleaning fluid of the motorisation system adapted to provide said injection device with cleaning parameters according to the clogging rate of the motorisation system. Thus, the fluid injection is adjusted taking account of a clogging rate of the motorisation system depending on the intrinsic parameters of the motorisation system, like for example, the geometry of the engine, the number and the diameter of the cylinders, etc., for a better effectiveness of the cleaning.
In the cleaning installation according to document FR3064026, moreover, a diagnostic means is arranged to determine a clogging rate of the motorisation system according to a defectiveness rate of at least one of the movable parts, and a control means arranged to provide the injection device with cleaning parameters for the implementation of the cleaning sequence, said cleaning parameters according to the clogging rate of the motorisation system. Thus, the cleaning fluid injection is adjusted taking account of a clogging rate of the motorisation system according to a defectiveness rate of at least one movable part. The cleaning sequence is thus adapted to the real need of the engine, and not based only on a statistical clogging state of the engine.
The state of the art summarised above reveals that the general principle of descaling an internal combustion engine by hydrogen injection forms the subject of continuous improvements, mainly resulting from interaction with the vehicle specifically in question by the current operation.
However, it seems that this interaction with said vehicle, even if it makes it possible to take account of the state of the vehicle just before the performance of the operation, can also be improved.
In particular, all internal combustion engines of modern vehicles are electronically managed, by one (or more) on-board management boxes. These management boxes each comprise at least one computer which controls the operation of the engine according to various parameters, like the engine system (slowing down, acceleration, etc.), the engine's charge (full charge, engine brake, etc.), the acceleration request (deceleration, resumption), the engine's temperature, the operating phase (cold start-up, city journey with frequent stops and restarts if a “stop and start” function is implemented, etc.), and others too. Thanks to this technology, all the factors of good operation are taken into account to adjust certain engine control parameters, like the duration of the injection, the moment of pre-injection, the injection and the post-injection, etc.
The clogging of the engine, which forms part of the parameters associated with the ageing of engine parts, is also taken into account by these electronic management boxes of the engine, as a slow development parameter.
This being so, injecting hydrogen in order to remove or reduce scale inside the engine during a descaling operation, has the effect that the electronic management of the engine is suddenly no longer in phase with the real state of the parts which are more particularly subject to scaling. These parts are indeed, from the standpoint of electronic management boxes of the engine, considered as intrinsically clogged with the effect of reducing the efficiency of their operation with respect to what was commissioned of the engine. However, these parts are found to be, all of a sudden, partially or totally regenerated due to the descaling operation which has just been carried out. For this reason, the parameters taken into account by the electronic management boxes of the engine which are linked to clogging (valve lift height, injector opening rate, DPF scaling rate, etc.) become at least partially erroneous as soon as the ageing effects attributed to the progressive formation of scale in the engine totally or partially disappear due to the descaling operation carried out.
The invention aims to improve the situation and proposes, to this end, in substance, to inform all of the electronic management boxes of the engine to carry out a descaling operation. Thus, the electronic management of the engine can take account of the resetting (i.e. to the initial values or to values closes to said initial values) of the operating parameters of the engine which are sensitive to the scaling of the engine, like EGR valve mobility, valve lift, DPF clogging, injector needle mobility, etc.
This aim is achieved, thanks to a cleaning method involving a motorisation unit diagnostic tool, which can interact with the control electronics system of the engine, not only for reading information and controlling certain members during the cleaning procedure, but which further can vary the state of the members impacted by the cleaning and updating of the management parameters of the engine in real time accordingly in the control electronics system of the motorisation unit.
More specifically, a method for cleaning a motor vehicle motorisation unit comprising an internal combustion engine is proposed, said method comprising:
Embodiments, taken individually or in combination, further provide that:
In a second aspect, the invention also aims for a diagnostic tool adapted to be operationally connected to a cleaning station, by injection of a cleaning fluid, of a motor vehicle motorisation unit comprising an internal combustion engine, said diagnostic tool comprising means for the implementation of all the steps of the method according to the first aspect above.
A third aspect of the invention relates to a cleaning installation of a motor vehicle motorisation unit comprising an internal combustion engine, said installation comprising a cleaning station adapted for the injection of a cleaning fluid in the motorisation unit, engine turned on, and a diagnostic tool according to the second aspect above, adapted to be operationally connected to a cleaning station in order to implement the method according to the first aspect.
In a fourth and last aspect, the invention also aims for a computer program product comprising one or more instruction sequences stored on a memory medium which can be read by a machine comprising a processor, said instruction sequences being adapted to carry out all the steps of the method according to the first aspect of the invention when the program is read in the memory medium and executed by the processor.
A drop of 10 to 38% of consumption for a depolluted vehicle can be noted, thanks to the implementation of the invention. The system proposed, in view of such costed elements, demonstrates its effectiveness, as well in terms of energy saving, as regarding respecting the environment and taking account of the public health problems linked to air quality.
Other features and advantages of the invention will also appear upon reading the following description. This is purely illustrative and must be read regarding the accompanying drawings, wherein:
In the description of embodiments below and in the figures of the accompanying drawings, the same elements or similar elements have the same numerical references to the drawings.
An internal combustion engine discards, during its operation, gases and damaging products such as;
Despite the efforts implemented to reduce these emissions, in particular by reducing fuel consumption by combustion engines, but also by implementing depollution techniques, the impact of human activities involving the use of combustion engines remains concerning for the planet and for humanity.
Descaling is a method for cleaning motorisation units comprising an internal combustion engine, which contributes to reducing emissions of abovementioned pollutant products, by fighting against the accumulation of carbon soot in the members in question, which is responsible for the drop in performance of vehicles and the increase in pollutants with the age of the vehicle.
It is reminded that the technique of descaling a combustion engine by hydrogen injection consists of injecting hydrogen inside the engine, while the engine operates with low revs. This hydrogen is produced only as demineralised water-based. No chemical product is added. That is why, and although other cleaning fluids can be considered, hydrogen is currently the most common. That is also why the embodiments considered here relate to a cleaning of a motorisation unit by hydrogen injection. A person skilled in the art will assess, however, that the implementation of the invention is not limited to this example.
The hydrogen injection in particular makes it possible:
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In an embodiment, the diagnostic tool can be a connected tablet, associated with the cleaning station 20, or a functionally equivalent device like a smartphone or a laptop computer, equipped with software and an interface to communicate with the on-board computers of the control electronics system 32. In a variant, it can be a diagnostic case available on the market equipped with software for vehicles of the main makes (this can also be called “multi-make case”), or a desktop computer, equipped in the same way, and equipped with an interface to communicate with the on-board computers.
It will be noted that, in all the embodiments, the diagnostic tool is sold with no software and no datafile corresponding to cleaning procedures. The user of the cleaning station can apply exclusive procedures that they will have developed closely with the cleaning station that they use in relation to the connected diagnostic tool.
They can also install in the diagnostic tool 10, diagnostic software 110 corresponding to the different types of motor vehicles managed in their workshop (light-duty passenger vehicles, heavy-duty utility vehicles, farming vehicles, site vehicles, boats and ships, diesel engine railway vehicles, aircraft, etc.), and if necessary, a customer file 120 which will seem the most suitable for them.
For example, the diagnostic tool 10 can be connected to the control electronics system 32 of the motorisation unit 31 by way of the OBD connector, referenced 34, of the vehicle 30, via an interface cable 14. The OBD standard is the only standard for all motor vehicle manufacturers. It is the on-board diagnostic standard, which aims to enable the control of pollutant emissions by being capable of detecting the probable origin of a malfunctioning by means of error codes stored in the memory of the computer, in particular during technical control sessions. According to the specifications of this standard, applicable in Europe, furthermore, when a major OBD fault code is detected, the computer illuminates the engine depollution light on the dashboard. In a variant, the operational connection between the tool 10 and the control electronics system 32 can also occur by other means, wired or wireless.
By the expression, connected tablet “associated” with the cleaning station 20, this means that it can be provided with said cleaning station, by the manufacturer of the latter. But, this can also be a digital tablet available on the market, smart and connecting, wherein an app can be executed which implements the method and which comprises operational connection means, wired or wireless, with the cleaning station 20. In summary, the diagnostic tool 10 can be connected to the cleaning station 20 by way of a wired connection 23, 13 like a USB™ connection established by a USB™ cable 23 of the station with a USB™ connector 23 of the tool 10, for example a USB-3™ connection, or by a wireless connection, for example a Bluetooth™ connection or a Wi-Fi™ connection.
The cleaning station 20 further comprises a pipe 21 to deliver the cleaning fluid, in this case hydrogen, to the motorisation unit 31 of the motor vehicle 30, via a means for ad-hoc connecting to the vehicle. More specifically, hydrogen is injected into the inlet of the engine, for example, via the air inlet hose (or conduit). This can occur downstream from the air filter, for a positive ignition vehicle (or so-called “petrol” vehicle), or downstream from the EGR valve for a diesel vehicle.
Finally, [
In reference to the step diagram of [
First, it will be noted that a standard implementation of an engine cleaning by hydrogen injection according to the prior art comprises the following steps, implemented by an operator in a specialist workshop
In step 201 of the method according to the embodiments of the invention illustrated by the step diagram of [
In step 202, the diagnostic tool 10 performs the reading of faults of the motorisation unit possibly highlighted by the control electronics system 32 of the motorisation unit comprising the internal combustion engine 31, during the prior operation of the motorisation unit. Such faults are conventionally stored, if necessary, in a non-volatile memory of the control electronics system 32, for example an EEPROM (Electrically Erasable and Programmable Read-only Memory) memory, or a Flash memory.
Step 203 comprises the reading by the diagnostic tool 10, in real time and engine turned on, of operating parameters of the motorisation unit. It also comprises the establishment, always by the diagnostic tool 10, of a diagnosis relating to the clogging of members of the motorisation unit according to the faults highlighted, if necessary, as well as the operating parameters of the motorisation unit read in the memory of the electronics 32. A person skilled in the art will assess that these are members of the motorisation unit which are sensitive to clogging by carbon residue (scale), in particular the turbo, the diesel particle filter, the EGR valve, the bypass box, the exhaust valve, the valves controlled by the variable valve timing (VVT) system, and the injectors. This list is not exhaustive.
In step 204, the operator performs the connection to the vehicle 30 of the cleaning station 20, which is adapted to ensure the cleaning of the motorisation unit by injection of a cleaning fluid, namely hydrogen in the example. The cleaning station 20 is further connected to the diagnostic tool 10 to perform under the control of said diagnostic tool, in the scope of the cleaning procedure established by this tool.
This cleaning procedure is, for example, established based on standard procedures, one of which is selected and adapted (by the configuration of ad-hoc parameters, for example) according to the faults noted in step 202 and from the diagnostic established in step 203, in particular.
In a first example, if faults are noted and/or if malfunctions are observed at the EGR system, the cleaning procedure can provide:
In a second example, if faults are noted and/or if malfunctions are observed at the diesel particle filter (DPF), the cleaning procedure can provide:
In a third example, if faults are noted and/or if malfunctions are observed at the EGR system, the cleaning procedure can provide:
A person skilled in the art will assess that these examples are not limiting at all.
The cleaning procedure can also, generally, provide that the cleaning of the engine will be performed for a duration which further depends on intrinsic parameters of the motorisation unit, like the engine's cylinder, the age and/or the total mileage travelled by the vehicle since it was commissioned, etc. Other more subjective parameters, like the type of dominant use of the vehicle (small, daily journeys on city routes, or on the contrary, occasional, long journeys on the motorway, for example) and directly entered by the operator in the diagnostic tool 10 (insofar as they are known) or collected from the customer datafile 120, for example, can also be taken into account to establish the cleaning procedure most suitable for the particular case of the vehicle to be descaled.
In step 205, the diagnostic tool controls the cleaning of the motorisation unit by injection, engine turned on, of the cleaning fluid in the inlet of the engine, namely hydrogen in the example considered in this case. During this step, and at the same time as the hydrogen injection is performed, the movable members of the motorisation unit comprised among the members of said motorisation unit which are sensitive to clogging are preferably moved, according to the methods belonging to the cleaning procedure mentioned in the preceding paragraph, which depends on the diagnosis established. For example, the movable members of the motorisation unit among the members of said motorisation unit which are sensitive to clogging comprise the turbo, the EGR valve, the exhaust valve, the valves and the injectors. This list is not exhaustive.
In step 206, the diagnostic tool controls the removal of faults highlighted before cleaning, if necessary, of the memory of the control electronics system 32 of the motorisation unit of the vehicle 30.
In step 207, the diagnostic tool 10 further learns, after the cleaning operation, in real time and engine turned on, of the effective state of the self-adaptive members of the motorisation unit which are comprised among the members of said motorisation unit which are sensitive to clogging. For example, the self-adaptive members of the motorisation unit among the members of said motorisation unit which are sensitive to clogging comprise the EGR valve, the exhaust valve and the valves (through the VVT system). This list is not exhaustive either.
Finally, in step 208, the diagnostic tool performs the update, in the control electronics system 32 of the motorisation unit of the vehicle 10, operating parameters of said motorisation unit which are normally impacted by the clogging of members which are sensitive to clogging. This makes it possible, advantageously, to take account of the effective state, after the cleaning operation, of the self-adaptive members of the motorisation unit among the members of said motorisation unit which are sensitive to clogging. In other words, the operation of the motorisation unit after cleaning by hydrogen injection will take account of the return of said members to an identical state to or close to their initial state, during the commissioning of the vehicle 10. The reduction of consumption and fuel and the emission of damaging products into the atmosphere are therefore optimised, likewise the performance of the vehicle.
A person skilled in the art will assess that the order of step 206, on the one hand, and steps 207 and 208, on the other hand, is indifferent.
The present invention has been described and illustrated in the present detailed description and in the figures of the accompanying drawings, in possible embodiments. The present invention is not limited, however, to the embodiments presented. Other variants and embodiments can be deduced and implemented by a person skilled in the art upon reading the present description and the accompanying drawings.
In the claims, the term “comprise” or “has” does not exclude other elements or other steps. One single processor or several other units can be used to implement the invention. The different features presented and/or claimed can be advantageously combined. Their presence in the description or in different dependent claims, do not exclude this possibility. The reference signs could not be understood as limiting the scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| FR2005353 | May 2020 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/053977 | 5/11/2021 | WO |
