RU2588326C2 - Method and system for cleaning filter - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: group of inventions relates to particulate filter cleaning and to system with silencer and particulate filter. Vehicle is equipped with internal-combustion engine and particulate filter arranged in working position inside exhaust system silencer at normal engine operation. Purification process is performed as follows: particulate filter is disconnected and removed from first end of silencer. Further, particulate filter is turned to opposite direction and again installed in cleaning position on said first end of silencer. Then engine is started and its operation is controlled by adjusting frequency of rotation in accordance with given cycle until specified condition is achieved. Engine is stopped and particulate filter is returned into working position inside exhaust system silencer.

EFFECT: group of inventions enables improving methods and systems for particulate filter cleaning in vehicles using available flow of exhaust gases.

20 cl, 11 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a method and system for cleaning a diesel particulate filter, and more specifically, a method and apparatus for cleaning a diesel particulate filter in situ using an exhaust gas stream.

State of the art

A diesel particulate filter removes organic and inorganic solid particles from the exhaust stream of a diesel engine. Organic particles are a complex mixture of carbon, hydrogen and oxygen and result from incomplete combustion of diesel fuel in the engine cylinders. Sources of the inorganic part of the particles are materials added to oil or fuel, as well as particles resulting from erosion of engine parts. The bulk of these inorganic substances are metal sulfates, for example, calcium sulfate. These substances will gradually clog particulate filters. Under optimal conditions, organic particles will completely burn out during the regeneration of the particulate filter and exit it in the form of gaseous products, CO ₂ and H ₂ O. As for the inorganic component, it cannot be oxidized inside the filter and converted into gaseous products. As a result, it slags the filter in the form of various oxides, generally referred to as “ashes”. To ensure acceptable performance, ash must be periodically removed from the filter to prevent clogging.

In some cases, diesel particulate filters are installed on engines whose operating temperature is too low and does not ensure proper filter regeneration, for example, by oxidizing organic components. In these cases, the filter may be clogged with solid particles, and engine performance may be reduced. In addition, for filters with high soot levels, the likelihood of permanent damage due to uncontrolled regeneration increases the likelihood of damage compared to filters with low soot levels. In these cases of insufficiently high operating temperature, regular soot removal may be necessary.

Known technical solutions to the filter cleaning problem described below are often complex or contain moving parts, and other solutions for removing solid particles firmly bound to the filter surfaces are ineffective. Other solutions may result in high particulate emissions during the cleaning process.

Below are some examples of different approaches (for example, devices and methods) and their disadvantages.

I. Cleaning the diesel particulate filter removed from the engine

The filter is simply cleaned using compressed air, which is supplied through a hose. Compressed air is directed into the outlet of the filter for blowing soot from its walls in the opposite direction (blowing in the opposite direction). This method does not guarantee success, it is potentially dangerous (dangerous factors of compressed air), requires the full attention of the operator and, in case of an error, can lead to the emission of harmful particles from the filter, or as a result, a poorly cleaned filter can be obtained.

A dirty filter can be heated in a furnace to a high temperature to effectively remove particles whose main component is carbon. In this case, a lot of energy is consumed, and the inorganic component of the soot is not removed. After a heating cycle, cooling can take a long time and the ash must be removed using a vacuum or washing the filter.

Many industrial device cleaning systems use a combination of fluid flow and ultrasound, which can be effective, but costs are high in this case. In addition, the cleaning fluid can damage the catalytic coating or matrix material, which fixes the catalyst in a metal casing.

Other methods use cleaning systems that include backwashing a suitable cleaning fluid until the filter is clean. However, many catalysts and matrix materials are sensitive to large amounts of water or solvents. An additional disadvantage of solvents is the need for their disposal. In addition, local control of the flow of the cleaning fluid is not provided (that is, one fluid flow flows through the filter), so some sections of the filter will not be cleaned to the same extent as others.

The problem with this solution is that not all service stations may have suitable equipment for cleaning particulate filters. In this case, it is necessary to use a replacement filter, which will work as long as the dirty filter is cleaned. This requires maintaining a stock of fairly expensive filters at a service station or in an automobile company so that replacement filters are constantly provided.

II. Cleaning the particulate filter while it is on the engine

Methods for collecting particulate matter using multiple filters with valves to control the flow path are described in a number of patent documents.

For example, US Pat. No. 5,930,994 discloses a combination of valve settings that allows one of the filters to be purged with a reverse flow, i.e. The gas flow direction is reversed to blow the soot out of the filter. The return air stream can be heated to burn soot as it passes through the filter.

US 5,725,618 discloses a method for backflushing a particulate filter to remove soot and ash accumulated in the filter. The filter is back-flown when it is mounted on a vehicle, in which case a shock wave valve is used that provides a pressure wave to drive particles out of the filter. To ensure that the entire particulate filter is cleaned, the filter block is rotated so that the air flow provided by the pressure wave valve acts on a specific section of the filter.

A drawback of the above backflushing methods is that the ash generated from the lubricating oil cannot be removed from the filter, since the ash blown from one section of the filter is transferred to another section, and in this case, manual cleaning is also required. In addition, the material ejected from the filter must somehow be removed from the exhaust pipe.

III. Swivel channels

Another method of cleaning a diesel particulate filter involves using a device with a rotating electric heating element. Part of the exhaust gas stream passes through a rotating tube above the heating element. The combination of low flow rate and high temperature increases the likelihood of successful regeneration.

US 5,116,395 discloses a dust collector with an integrated programmable cleaning controller. In this case, a rotating tube with many nozzles is used, which provides a backflush flow to remove particles from the surface of the filter elements / cartridges and direct them to the collection chamber. The controller provides control of the tube and nozzles to produce strong flows of cleaning fluid above a plurality of filter cartridges. The tube also contains a sensor to determine the degree of contamination of each filter cartridge (the use of a pitot tube is provided). The system disclosed in this patent contains several structural elements that make this system unsuitable for cleaning diesel particulate filters. Firstly, the sizes of diesel particulate filters are much smaller than the sizes of dust collectors, and the sizes of nozzles above it are designed for large filters. The diameter of a typical diesel particulate filter ranges from 15 cm to 32 cm. The diameter of the dust collector disclosed in the patent is much larger. Secondly, diesel particulate filters have many thousands of cells (passages), and the direction of air flow into each cell is almost impossible. Other similar dust collector designs have similar disadvantages.

An object of the present invention is to provide an improved method and system for cleaning a vehicle particulate filter using an existing exhaust stream to overcome the problems mentioned above.

Disclosure of invention

The above problems are solved by the method and system in accordance with the attached claims.

In the following text, terms such as “longitudinal” and “transverse” are used to indicate directions relative to the main direction of movement of the vehicle. Similarly, terms such as “front” and “rear” are used to determine the relative position of a component relative to a specified direction of movement.

The invention relates to a method for cleaning a diesel particulate filter of a vehicle equipped with an internal combustion engine, where the diesel particulate filter is installed in the working position inside the muffler of the exhaust system (exhaust) during normal engine operation. The method performs a cleaning process, including the steps in which:

the particulate filter is disconnected and removed from the first end of the muffler;

turn in the opposite direction (turn 180 degrees) and reset the filter to the cleaning position on the said first end of the muffler;

start and control the operation of the engine by adjusting its speed (speed) in accordance with a predetermined (predefined) cycle until a predetermined state is reached;

they stop the engine and return the particulate filter to its working position inside the muffler of the exhaust system.

The engine speed is controlled so that the particulate filter is cleaned by a pulsating flow of exhaust gases from the engine. The engine speed varies between the upper and lower limits a predetermined number of times during at least one cycle, and a value representing the said predetermined state is measured at the end of said at least one cycle. According to a non-limiting example, the engine speed may vary from a lower limit selected within a range of 700 to 1100 rpm to an upper limit selected within a range of 1500 to 1800 rpm. During each cycle, the engine speed is changed between the upper and lower limits a predetermined number of times over a predetermined period of time. According to a non-limiting example, the number of times can be selected from 60 to 120, and the time period can be selected from 60 to 240 s. The total time that the complete cleaning process takes can be from 10 to 20 minutes. The above values are given only as examples, while the choice depends on the type and size of the engine, the size and degree of contamination of the particulate filter and the type of equipment available to carry out the cleaning process, as will be described below.

Before the start of the first cycle, the engine speed increases to a stable value over a period of time sufficient to stabilize the temperature of the exhaust gases (exhaust) in the muffler. The stabilized value for the engine speed is preferably at least equal to said upper limit, but can be selected above or below this upper limit. Then, a quantity representing said predetermined state, such as a pressure drop through a silencer or filter assembly, is measured and a first cycle is initiated. The result of the first measurement can be compared with the stored value from the previous cleaning process to determine the degree of contamination / clogging. If the filter was replaced during previous maintenance, then the reference value for a clean filter can be used.

At the end of said at least one cycle, the engine speed is increased to a value exceeding said upper limit for a predetermined period of time, and at least one value representing said predetermined state is measured. Depending on the type of measured value, such as the pressure at a suitable point in the exhaust pipe, it may be useful or required to allow the temperature of the exhaust gases to stabilize before taking readings in order to obtain a correct measurement result. Said cycle is repeated until said predetermined state is reached or until the maximum number of cycles is completed. The value representing said predetermined state may be exhaust back pressure or pressure drop through the particulate filter. Most modern engines are equipped with exhaust gas pressure sensors (exhaust) to monitor various parameters during normal engine operation. If required, one or more pressure sensors can be provided in a silencer or particulate filter if standard sensors are not available.

According to one example, the method can be implemented by adjusting the engine speed during the cleaning process using an electronic control unit. The electronic control unit may be an electronic engine control unit or an external electronic control unit. The electronic control unit can be pre-programmed, according to which the software required to run the cleaning program is stored in non-volatile memory or on the hard disk in the electronic control unit. Alternatively, the necessary software can be stored on a portable portable device or non-volatile memory unit, such as a USB stick or flash memory, which can be connected to an electronic control unit or engine control unit. In this context, non-volatile storage device for storing data is defined as including systems with electrical addressing, such as read-only memory (ROM), or systems with mechanical addressing, such as hard drives, optical disks, magnetic tapes, storage devices on holograms, etc.

The measurement results of the mentioned value from the previous cleaning process can be stored in the specified electronic control unit and can be used to set (set) a given state. Thus, it is possible to compare the current readings for this value with the values from previous periods when the filter was cleaned or last changed. In this way, monitoring of the mode or current state of the particulate filter and the calculation of the expected service life can be ensured.

It is also possible to store the measurement results of at least one value related to engine operation since the previous cleaning process in said electronic control unit for setting a predetermined state. According to one example, the measured pressure drop through the particulate filter at the end of the previous cleaning process can be taken as a target parameter for a given state. Additional factors that can be taken into account when setting a preset condition may include the distance traveled, engine runtime, or fuel and / or oil consumption since the previous cleaning process.

If it is established that a particulate filter cleaning process is required in an environment where an electronic control unit is not available to carry out this process, a simplified urgent cleaning process may be performed. According to this example, the engine speed is manually changed between the upper and lower limits, while measuring the time from the beginning of the first cycle. The pulsating flow is achieved by pressing the gas pedal with a given frequency, while monitoring the readings of the tachometer or engine speed sensor to control the upper and lower limits of engine speed, respectively. This operation can be performed for a given number of cycles or for a period of time estimated as sufficient for efficient filter cleaning. The diesel particulate filter can then be flipped back to its operating position and the engine will again be ready for operation.

The invention also relates to a system comprising a silencer of a vehicle exhaust system and a particulate filter mounted in a working position inside a silencer of an exhaust system during normal operation of an engine connected to this silencer. The particulate filter has a first contact surface facing the first end of the muffler and is in tight (sealed) contact with the corresponding surface at the first end of the muffler when the particulate filter is in its working position. The particulate filter also has a second contact surface that is in close contact with the corresponding surface at the first end of the muffler when the particulate filter is in the cleaning position.

The particulate filter is placed inside the muffler in its operating position, and the particulate filter is turned upside down (rotated 180 degrees) and placed at least partially outside the first end of the muffler in the cleaning position of the filter.

The first and second contact surfaces are made on opposite sides of the flange around the outer surface at one end of the particulate filter. Each of the first and second contact surfaces includes an annular contact surface, made identical and as a mirror image relative to the plane through the flange at right angles to the central axis of the particulate filter.

The system includes an ash collector attached to the end of the particulate filter, remote from the muffler, when the particulate filter is in the cleaning position. The ash collecting device is preferably attached to the annular sealing surface of the particulate filter remote from the muffler when the particulate filter is in the cleaning position. Examples of such ash collecting devices include from a filter element / bag attached to the end of the particulate filter, to a hose connector with a hose connected to a suction means for removing ash. The removed ash can be recovered from the exhaust gases by means of a suitable gas treatment device, such as a water irrigation scrubber, a cyclone cleaner, an electrostatic filter or the like.

The invention also relates to a computer program containing software coding for performing all the steps of the method described above, when the specified program is executed on a computer. The invention also relates to a computer program product containing software encoding means stored on a computer-readable medium / medium for performing all the steps of the method described above when executing said software product on a computer. Finally, the invention relates to a computer system for implementing a method of cleaning a particulate filter in a vehicle having a memory (memory) for storing software encoding means and a processor capable of executing program code to perform all the steps of the method described above.

Brief Description of the Drawings

The invention is described below in detail with reference to the accompanying figures. You must understand that the drawings are intended solely to illustrate the invention and should not be used to establish its scope, which is determined by the attached formula. You must also understand that the drawings are not necessarily made to scale, and that, unless otherwise indicated, they are intended only to schematically illustrate the structures and methods described below. The accompanying figures of the drawings show:

in FIG. 1 is a view of a vehicle equipped with a particulate filter cleaning apparatus of the invention;

in FIG. 2 - view of the muffler with the particulate filter in the working position;

in FIG. 3 is a view of a disassembled muffler with a particulate filter;

in FIG. 4 is a view of a muffler with a particulate filter in the cleaning position;

in FIG. 5 is a view of a muffler with a particulate filter connected to a suction means for extracting ash;

in FIG. 6a is a schematic sectional view of the silencer of FIG. 2;

in FIG. 6b is a schematic sectional view of an alternative silencer;

in FIG. 7 is a schematic sectional view of the silencer of FIG. four;

in FIG. 8 is a schematic diagram of a change in engine speed over time when cleaning a particulate filter;

in FIG. 9 is a schematic diagram of the pressure drop through the muffler in time when cleaning the particulate filter;

in FIG. 10a is a schematic view of an internal combustion engine and an exhaust system of a vehicle of FIG. one;

in FIG. 10b is a schematic view of an internal combustion engine and an alternative exhaust system;

in FIG. 11 is a block diagram of an embodiment of the invention in a computer system.

The implementation of the invention

In FIG. 1 is a schematic view of a commercial vehicle 1 in the form of a heavy truck. Commercial vehicle 1 has a chassis 2 and a driver's cab 3 mounted on the chassis. Under the driver’s cabin 3 there is an internal combustion engine 4, the power of which is transmitted to the driving wheels 6 of the vehicle 1 by means of a transmission 5, which includes a clutch and gearbox with manual or automatic control. The internal combustion engine 4 comprises an exhaust system 7 with a silencer 8 provided with a system for post-treatment of exhaust gases and a second silencer 9 (see FIG. 10a) connected to an exhaust pipe / silencer pipe (not shown) through which exhaust gases are discharged in atmosphere. The second muffler and exhaust pipe may be located on one side of the chassis, for example, or extend upward behind the driver's cab. The location of these components is not related to the invention and will not be further described in detail. The invention can also be used without these components.

The first muffler 8, which is mounted on a commercial vehicle 1 (FIG. 1) next to the internal combustion engine 4 on the chassis frame 2, may have the structure shown in FIG. 1-5. The muffler 8 is made in the form of a drum having a front end wall 11 and a rear end wall 12, both end walls 11, 12 being connected by an external wall having at least partially cylindrical shape. For normal operation, an inlet pipe 13 and an outlet pipe are provided in the front end wall 11. Within the scope of the present invention, one or both of the inlet and outlet pipes can be located on the outer wall 10. The muffler 8 also has an inner dividing wall extending in the inner the space of the muffler and the separating muffler 8 into two internal chambers (volumes) 15, 16. These chambers 15, 16 can be seen in FIG. 6a, which shows a sectional view of a muffler 8 with a particle filter 18 in its working position. As shown in FIG. 6a, the first chamber 15 comprises first exhaust gas purification means in the form of an oxidizing converter 17 located downstream of the inlet pipe 13 and above the particle filter 18, which in this case is a diesel particulate filter having a generally cylindrical shape. The second chamber 16 contains exhaust gas purification means in the form of a selective catalytic reactor 20, located upstream of the exhaust pipe 14. The first 15 and second 16 of the chamber are connected by a channel 19 having a generally U-shaped shape, which extends from the first hole 21 to the second hole 22 in the rear end wall 12.

In FIG. 6b schematically shows a sectional view of an alternative embodiment of a silencer. In this alternative embodiment, the silencer includes substantially the same components as the silencer of FIG. 6a, with the difference that in this embodiment, the silencer comprises a first silencer block 8a and a second silencer block 8b. Moreover, in FIG. 6b, the same reference numbers are used as were used for identical components in FIG. 6a. The first silencer unit 8a contains the same components as the first silencer chamber 15 of FIG. 6a, while the second silencer unit 8b contains the same components as the second silencer chamber 16 of FIG. 6a. The first and second chambers 15, 16 are surrounded by the first and second outer walls 10a, 10b, respectively. This arrangement allows you to install these blocks 8A, 8b at a distance from each other, connected by a channel / pipe 19a. Accordingly, the first muffler unit 8a comprises a particulate filter 18, accessible by removing the pipe 19a.

In FIG. 3 shows a disassembled part of the muffler 8, from which the particulate filter 18 and the U-shaped channel 19 are removed. As shown in FIG. 3, the first hole in the rear end wall 12 contains a tubular outlet with a first flange 23. The first flange 23 is designed to interact and seal relative to an annular flange 24 located near the rear, first end 25 of the particulate filter 18. A first sealing is located between the flanges 23, 24 ring 26 to provide a gas tight seal during normal operation. For the same purpose, a second O-ring 27 is located between the annular flange 24 and the first flange 28 at the inlet end of the U-shaped channel 19. Similarly, between the second flange 30 at the outlet end of the U-shaped channel 19 and the second flange 31 at the second hole in the rear end a third O-ring 29 is located on the wall 12. To hold the particulate filter 18 in position, the first and second annular clamps 32, 33 are used, pressing the first and second flanges 28, 30 on the U-shaped channel 19, respectively, to the first and second flanges 23, 31 n the rear end wall 12. The first and second annular collars 32, 33 have a generally U-shaped cross-sectional profile, which allows them to be installed on the respective flanges and tightened to seal the connection between the first and second chambers inside the muffler 8. The first collar 32 is also used to press the soot filter 18 to the first flange 23 of the rear end wall 12 when the filter is in the deployed position (180 degrees). This type of clamp is well known in the art and is not described in detail here. The above seals may be integral parts of the sealing surfaces and / or may contain separate removable seals, such as o-rings.

The annular flange 24 is shaped so that its outer contact surface is pressed with a seal to the first flange 28 of the U-shaped channel 19 and to the first flange 23 of the rear end wall 12. This allows the particulate filter 18 to be removed from its operating position in the muffler 8, as shown in FIG. 3, and its rotation with subsequent installation on the first flange 23 of the rear end wall 12 in the cleaning position of the filter, as shown in FIG. four.

In FIG. 4 shows a muffler 8 and a particulate filter 18 in the position to perform the cleaning operation of the filter 18, with its end side (end) 35 in the normal position facing the inlet pipe 13 on the front end wall 11 in communication with the atmosphere. When the U-shaped channel 19 is removed and the particulate filter 18 is attached to the rear end wall 12, the entire exhaust stream will pass through the first chamber 15, since the second chamber 16 is bypassed. This can be seen in FIG. 7, which shows a sectional view of the muffler 8 with the particulate filter 18 in the cleaning position of the filter. In FIG. 7 it is seen that the exhaust gases pass from the inlet pipe 13, pass through the first chamber 15 and the particulate filter 18, and exit through the exhaust hose 37.

Installing the particulate filter 18 as described in relation to FIG. 6a and 8 is also applicable to the alternative silencer design of FIG. 6b.

During the cleaning operation, particles or ash displaced from the particulate filter are moved for reliable removal. In the example shown in FIG. 5, this is achieved by attaching the hose connector 36 to the open end 35 of the particulate filter 18. The connector 36 is provided with a hose 37 connected to a suction means (not shown) for removing ash, as shown by arrow 38. During the cleaning operation, the internal combustion engine starts, thereby the exhaust gases are fed into the inlet pipe 13, pass through the particulate filter 18 to remove ash and are discharged through the hose 37.

In accordance with the invention, the particulate filter is installed in the operating position inside the muffler of the exhaust system during normal engine operation. When it is determined that the filter is clogged and needs to be cleaned, the following steps are performed:

- disconnecting and removing the particulate filter 18 from the rear end wall 12 of the muffler 8;

- turning in the opposite direction (180 degree rotation) and reinstalling the filter 18 in the cleaning position on the rear end wall 12 of the muffler 8;

- starting and controlling the operation of the internal combustion engine 4, adjusting its speed in accordance with a predetermined cycle, until a predetermined state is reached;

- stopping the internal combustion engine 4 and returning the particulate filter 18 to the working position inside the muffler 8 of the exhaust system.

FIG. Figure 8 shows how the engine speed is controlled so that the particulate filter is cleaned by a pulsating exhaust stream from the engine. The engine speed varies between the upper and lower limits a predetermined number of times during at least one cycle C, and at the end of the at least one cycle C, a measurement is made representing the said predetermined state. According to the example of FIG. 8, the engine speed varies from a lower limit of approximately 900 rpm to an upper limit of approximately 1700 rpm. During each cycle, the engine speed changes between the upper and lower limits a predetermined number of times, in this case 15 times, over a given period of time, in this case approximately 180 s. The total time taken by the complete cleaning process can be 10-15 minutes, depending on the degree of filter plugging.

Before the start of the first cycle, the engine speed rises to a level above the upper limit, in this case 2,000 rpm, for a period of time sufficient to stabilize the exhaust gas temperature in the muffler. Then, a quantity representing said predetermined state is measured, in this case a pressure drop through the silencer, and a first cycle is initiated. The result of the first measurement is compared with the stored value from the previous cleaning process to determine the degree of clogging. If the filter was replaced during previous maintenance, then the reference value for a clean filter can be used.

At the end of each cycle, the engine speed is increased to the above level above the upper limit for a predetermined period of time and a value representing said predetermined state is measured again. As indicated above, the temperature of the exhaust gases is allowed to stabilize before taking readings in order to obtain the correct measurement result. Said cycle is repeated until said predetermined state is reached or until the maximum number of cycles is completed without reaching the predetermined state. The amount of pressure drop through the particulate filter to be achieved can be based on empirical values and read from the table, or based on stored pressure drop values from a previous cleaning operation. In FIG. 8 shows a series of three consecutive cycles, as described above.

In FIG. 9 is a schematic diagram showing the pressure drop through the silencer during the cleaning process. From this diagram you can see how the measured pressure drop values, shown as sharp protrusions on the schematic curve, constantly fall after each cycle. Using this curve, cycles can be repeated until a predetermined pressure drop is reached, two consecutive measurements show no or approximately no change, or until a predetermined elapsed time is reached when the process ends and stops.

In FIG. 10a shows a schematic layout of an internal combustion engine 4 and the exhaust system of FIG. 1 using the same reference numbers. As indicated above, the exhaust system includes a first muffler 8 provided with a post-exhaust system, and a second muffler 9 connected to an exhaust pipe that exhausts the atmosphere. Schematically shown, the first muffler 8 corresponds to the muffler shown in FIG. 6a. The electronic control unit 40 is connected to the first and second sensors 41, 42 of the exhaust gas pressure upstream and downstream from the muffler 8, respectively. The electronic control unit 40 is a conventional engine control unit connected to the internal combustion engine 4 by a control line 43. In the presented example, the internal combustion engine is a conventional diesel engine equipped with controllable fuel injectors 44, a turbocharger 45, and a sample air cooler 46. The engine itself will not be further described in detail. The electronic control unit 40 includes a microprocessor and non-volatile memory for storing and providing measured data. The presented exhaust system allows you to install the aforementioned first and second silencers 8, 9 at a distance from each other, which can be useful for layout purposes, when available space is limited.

In FIG. 10b is a schematic plan of an internal combustion engine and an alternative exhaust system. This alternative exhaust system contains substantially the same components as the system of FIG. 10a. The main difference between the two systems is that the silencer of FIG. 10b comprises a single silencer device with combined first and second silencers 8a, 9a. This single silencer device comprises both the first and second silencers 8, 9 shown in FIG. 10a. Schematically represented, the first muffler 8a corresponds to the muffler shown in FIG. 6a. This arrangement is shown with first and second silencers mounted together as a single silencer block 8a, 9a, which may have advantages in terms of access during servicing the exhaust system.

According to one example, the method can be carried out by adjusting the engine speed during the cleaning process using an electronic control unit. The electronic control unit may be an engine control unit, as shown in FIG. 10a and 10b, or an external electronic control unit that is connected to the engine control unit. The electronic control unit can be pre-programmed, according to which the software required to run the cleaning program is stored in non-volatile memory or on the hard disk in the electronic control unit. Alternatively, the necessary software can be stored on a portable portable device or non-volatile memory unit, such as a USB stick or flash memory, which can be integrated into or connected to an electronic control unit or engine control unit. In this context, non-volatile memory for storing data is defined as including systems with electrical addressing, such as read-only memory (ROM), or systems with mechanical addressing, such as hard drives, optical disks, magnetic tapes, storage devices on holograms and etc.

The measurement results of the mentioned value from the previous cleaning process can be stored in memory in the specified control unit and used to set a given state. Thus, it is possible to compare the current readings for this value with the values from previous periods of time when the filter was cleaned or replaced. In this way, monitoring of the mode or current state of the particulate filter and the calculation of the expected service life can be ensured. It is also possible to store the measurement results of at least one value related to the operation of the engine since the previous cleaning process in an electronic control unit for setting a predetermined state. According to one example, the measured pressure drop through the particulate filter at the end of the previous cleaning process can be taken as a target parameter for a given state. Additional factors that can be taken into account when setting a preset condition may include the distance traveled, engine runtime, or fuel and / or oil consumption since the previous cleaning process.

As noted above, the described method is particularly suitable for computer control. Since the present invention also relates to a computer program, a computer program product and a storage medium / storage medium for a computer should be used with a computer to implement this method.

In FIG. 11, the invention is shown in an appendix with an appropriate computer layout. The invention described below relates to a computer program containing software encoding for performing all the steps of the method described above, when the specified program is executed on a computer. The invention also relates to a computer program product containing software encoding means stored on a computer-readable medium / medium for performing all the steps of the method described above when executing said software product on a computer. Finally, the invention relates to a computer system for implementing a method of cleaning a particulate filter in a vehicle having a memory (memory) for storing software encoding means and a processor capable of executing program code to perform all the steps of the method described above.

In FIG. 11 shows a device 50 according to one embodiment of the invention, comprising a volatile memory 52, a processor 51, and a read and write memory 56. The memory 52 has a first memory part 53 in which a computer program for controlling the device 50 is stored. This computer program in a memory part 53 to control the device 50 may be an operating system. The device 50 may be enclosed, for example, in a control unit such as an engine control unit 40 shown in FIG. 10a. The data processing device 51 may include, for example, a microprocessor.

The memory 52 also has a second memory part 54 in which a program for controlling the desired gear selection function in accordance with the invention is stored. Alternatively, the program for setting said predetermined state and controlling the function of performing the cleaning process is stored on a separate non-volatile storage medium 55, such as, for example, a CD-ROM or removable semiconductor memory. A program can be stored in executable or compressed form.

When it is said that the data processing device 51 performs specific functions, it should be understood that the data processing device 51 executes a specific part of the program stored in the memory part 54 or a specific part of the program stored on the non-volatile storage medium 55.

The data processing device 51 is adapted to communicate with the storage medium 55 via the data bus 53. The data processing device 51 is also adapted to communicate with the memory 52 via the data bus 57. In addition, the data processing device 51 is adapted to communicate with the memory 56 via the data bus 58. And further, the data processing device 51 is also adapted to communicate with the data port 59 via the data bus 60.

The inventive method may be performed by a data processing device 51 executing a program stored in the memory 54 or a program stored on a non-volatile data medium 55.

The invention is not limited to the above examples and may include various changes within the scope of the appended claims.

Claims (20)

1. The method of cleaning the particulate filter of a vehicle equipped with an internal combustion engine and a particulate filter installed in the working position inside the muffler of the exhaust system during normal engine operation, characterized in that when performing the cleaning process:
the particulate filter is disconnected and removed from the first end of the muffler;
turn in the opposite direction and reset the particulate filter to the cleaning position on the said first end of the muffler;
start the engine and control its operation by adjusting the speed in accordance with a given cycle until a predetermined state is reached; and
they stop the engine and return the particulate filter to its working position inside the muffler of the exhaust system. 2. The method according to p. 1, characterized in that the engine speed is changed between the upper and lower limits a predetermined number of times during at least one cycle, and a value representing said predetermined state at the end of said at least one cycle is measured. 3. The method according to p. 2, characterized in that the engine speed is increased to a stable value for a predetermined period of time at the end of said at least one cycle, and a value representing said predetermined state is measured. 4. The method according to p. 3, characterized in that they stabilize the engine speed to a value equal to or greater than the upper limit for a predetermined period of time at the end of the at least one cycle and measure the value representing the specified state. 5. The method according to any one of the preceding paragraphs, characterized in that the cycle is repeated until the specified state is reached or until the maximum number of cycles is completed. 6. The method according to any one of paragraphs. 1-4, characterized in that they measure the value related to the backpressure of the exhaust gases, to determine the achievement of the specified state. 7. The method according to any one of paragraphs. 1-4, characterized in that they measure the value related to the pressure drop through the particulate filter, to determine the achievement of the aforementioned predetermined state. 8. The method according to any one of paragraphs. 1-4, characterized in that the regulation of the engine speed during the cleaning process is carried out using an electronic engine control unit. 9. The method according to any one of paragraphs. 1-4, characterized in that the regulation of the engine speed during the cleaning process is carried out using an external electronic control unit. 10. The method according to p. 8, characterized in that they store in the electronic control unit the measurement results of the aforementioned value from the previous cleaning process to set the desired state. 11. The method according to p. 9, characterized in that they store in the electronic control unit the measurement results of the aforementioned value from the previous cleaning process to set the desired state. 12. The method according to p. 8, characterized in that they store in the electronic control unit the measurement results of at least one value related to the operation of the engine since the previous cleaning process, to set a predetermined state. 13. The method according to p. 9, characterized in that they store in the electronic control unit the measurement results of at least one value related to the operation of the engine since the previous cleaning process, to set a given state. 14. The method according to p. 1 or 2, characterized in that the engine speed is manually changed between the upper and lower limits and the time from the start of the first cycle is measured. 15. A system comprising a vehicle silencer and a particulate filter installed in a working position inside this silencer of an exhaust system during normal operation of an engine connected to this silencer, characterized in that:
the particulate filter has a first contact surface facing the first end of the muffler and is in close contact with the corresponding surface at the first end of the muffler when the particulate filter is in its working position;
the particulate filter has a second contact surface in tight contact with the corresponding surface at the first end of the muffler when the particulate filter is in the cleaning position;
the particulate filter is placed inside the muffler in its working position, and the particulate filter is turned upside down and is at least partially located outside the first end of the muffler in the cleaning position. 16. The system according to p. 15, characterized in that the first and second contact surfaces are made on opposite sides of the flange around the outer surface at one end of the particulate filter. 17. The system according to p. 15, characterized in that each of the first and second contact surfaces includes an annular contact surface made identical and as a mirror image relative to the plane through the flange at right angles to the central axis of the particulate filter. 18. The system according to p. 15, characterized in that it includes a device for collecting ash attached to the end of the particulate filter, remote from the muffler, when the particulate filter is in the cleaning position. 19. The system according to p. 15, characterized in that it includes a device for collecting ash, attached to the annular sealing surface of the particulate filter, remote from the muffler, when the particulate filter is in the cleaning position. 20. The system according to p. 15, characterized in that the particulate filter is located in the muffler, and in the particulate filter, in turn, at least one selective catalytic reactor is placed.

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