AT522024A1 - Method and device for preloading a particle filter of an internal combustion engine and particle filter - Google Patents

Abstract

The invention relates to a method for pre-loading a particle filter, in particular an internal combustion engine, in which particles of a pre-loading material in a dispersion together with a fluid, in particular air, are introduced into the particle filter by means of a pressure difference between the inlet and outlet of the particle filter, the pressure difference in the Is chosen such that a mass flow of the fluid of greater than about 200 kg, preferably greater than about 300 kg and most preferably greater than about 400 kg per hour and per liter of filter volume of the particle filter through which flow occurs.

Description

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Method and device for pre-loading a particle filter

an internal combustion engine and particle filter

The invention relates to a method and a device for preloading a particle filter of an internal combustion engine, in particular an Otto engine.

Supercharged and supercharged internal combustion engines, especially diesel engines and gasoline engines, tend to generate emissions with very fine particles in the combustion process. Particle filters are used to limit the emission of particles from motor vehicles. These particle filters generally consist of a porous material such as ceramic with mutually closed channels. The exhaust gas flows through the material of the particle filter and the particles (especially soot) are retained by the particle filter. The degree of separation of the filter improves during a running-in phase due to the accumulation of the particles on the surface of the filter substrate or through the incorporation in its pores.

It is an object of the invention to provide a method and an apparatus to improve a separation performance of a newly produced particle filter. Another object is to provide an improved preloaded particulate filter.

This object is achieved by a device for preloading a particle filter of an internal combustion engine according to claim 11, a method for preloading a particle filter of an internal combustion engine according to claim 1 and a particle filter according to claim 18. Advantageous configurations are claimed in the dependent claims.

A first aspect of the invention relates to a device for precharging a particle filter of an internal combustion engine, in particular an Otto particle filter, having a dispersing device which is set up to disperse particles of a precharging material in a fluid for producing a dispersion, and a pumping device to set a pressure difference between To generate the inlet side and outlet side of the particle filter; and a mixing section, which is arranged downstream of the dispersing device and can be flow-connected to an inlet of the particle filter.

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The pump device generates a pressure difference between the inlet side and outlet side of the particle filter in order to bring about a mass flow of the fluid through the particle filter.

A second aspect of the invention relates to a method for preloading a newly produced particle filter of an internal combustion engine, in particular not yet containing any particles, in particular an Otto particle filter, in which particles of a preloading material in a dispersion together with a fluid, in particular air, by means of a pressure difference between The inlet and outlet of the particulate filter are introduced into the particulate filter, the pressure difference being set such that a mass flow of the fluid of greater than approximately 200 kg, preferably greater than approximately 300 kg and most preferably greater than approximately 400 kg per hour and per liter

flows through the filter volume of the particle filter.

A third aspect of the invention relates to a particle filter with channels which extend from an opening on an end face of an inlet side of the particle filter into the particle filter and are each closed off by a bottom which is opposite the opening, the channels, on average or all , starting from the floor to less than 1/10, in particular 1/20, the length of the channels from the opening to the floor are filled with pre-loading material.

A particle filter in the sense of the invention is preferably a filter body into which the preloading material is introduced and which is preferably available as an individual part for this purpose. However, the pre-loading can also be carried out on an assembly which contains this particle filter and is normally provided for installation in the exhaust line and is then also referred to in general parlance as a particle filter.

A filter substrate in the sense of the invention is preferably a material from which the actual particle filter consists.

Dispersing in the sense of the invention is preferably producing a dispersion.

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A pressure difference in the sense of the invention is preferably a difference in the pressure between the inlet side and the outlet side of the particle filter, by means of which a mass flow through the particle filter is started.

A differential pressure in the sense of the invention is preferably a pressure drop in the flow direction at the particle filter, which is based on the flow resistance of the particle filter.

A mass flow in the sense of the invention specifies an amount of the fluid as mass that passes through the filter per unit of time and through which the filter volume flows. The mass flow preferably relates to the mass flow which is present upstream of the dispersing device, the mass flow which is present downstream of the particle filter. More preferably, these mass flows are essentially the same, with non-filtered particles additionally being able to be present in the mass flow downstream of the particle filter. Since the preloading material has a higher density than the fluid into which it is dispersed and the flow velocity is not significantly influenced in this process, the mass flow of the dispersion (i.e. between the dispersing device and the particle filter) is greater than the mass flow of the pure fluid before and after this section. The mass flow is preferably measured on the pure fluid and corresponding quantitative information relates to this measurement. The mass flow of the dispersion, which is dependent on the concentration of the pre-loading material in the dispersion, results accordingly.

A pre-loading material in the sense of the invention is preferably a chemically inert substance. It is furthermore preferably a chemically inert substance which did not arise in a combustion process of an internal combustion engine. By using a chemically inert substance, undesired chemical changes to the filter are avoided and only the desired physical effects are brought about.

A filter volume in the sense of the invention preferably denotes a volume of

Filter body and results in the generally common prismatic designs from the product of the base and height of this filter body. That volume

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correlates with the effective filter area, but is generally easier to determine from the geometric dimensions.

The invention is based in particular on the knowledge that a particle filter, in particular an Otto particle filter, has an insufficient separation performance when new without soot or ash loading. According to the invention, this separation performance is improved by preloading the particle filter in the new state before the first use with a pre-loading material which is in particular chemically inert and is at least similar in particle size to the soot or ash

becomes.

During pre-loading, the pre-loading material accumulates in the pores of the particle filter and thereby reduces the pore cross-section. In particular, the preloading material is deposited on the lateral surfaces of channels or in the pores of the filter material that forms these lateral surfaces. In this way, the separation efficiency or the degree of separation of the particle filter in the assembled state is significantly increased compared to the new state, in such a way that it preferably essentially corresponds to the separation capacity of a particle filter that has run in as a result of a natural load caused by an internal combustion engine.

The process according to the invention partially closes the pores of the particle filter with the pre-loading material, so that the permeability of the filter substrate is reduced to a predefined level.

The method according to the invention can, in particular, shorten or even make a run-in phase of the particle filter until it achieves its nominal or required separation performance.

The values of the mass flow given in relation to the method achieve a flow velocity at which the momentum of the particles transported in the dispersion is sufficient to stably attach them to the filter substrate or in

to embed its pores.

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The parameters mentioned are preferably matched to one another in such a way that the pre-loading preferably takes less than a minute, in particular

less than 30 s.

If the filter is treated with the dispersion for a predetermined duration, the result is an essentially homogeneous distribution of the pre-loading material over the surface of the filter substrate. In particular, the flow resistance increases in partial areas of the flowed through filter area that are already saturated with particles. This leads to a more intensive flow and thus particle deposition in the previously less saturated areas. The necessary duration of the flow thus depends on the mass flow, the concentration of the dispersion, the ratio of particle and pore size, the particle size itself and the effective filter area.

In an advantageous embodiment of the method according to the invention, the main direction of flow through the particle filter at least essentially corresponds to the direction of flow in real operation of the internal combustion engine. The preloading material is introduced into the particle filter from the inlet side of the particle filter, that is to say the end face facing the internal combustion engine during real operation. This also favors a largely homogeneous distribution of the particles of the pre-loading material in the particle filter, which largely corresponds to that which results as the loading state after a real running-in phase.

In a further advantageous embodiment of the method according to the invention, a duration of the discharge of the particles and / or a throughput of the pre-loading material is set such that the particle filter at the end of the method with approximately 3 g to approximately 20 g per liter filter volume, preferably approximately 10 g to approximately 15 g per liter of filter volume with which the pre-loading material is pre-loaded. This results in a particularly advantageous separation performance.

In a further advantageous embodiment of the method according to the invention, the preloading material is preconditioned, in particular dried, tempered and / or loosened, so that it has a predefined moisture content, a predefined temperature and / or the consistency required for further processing. In this way it can be achieved that the particles of the pre-loading material

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distribute evenly in the dispersion. This favors a homogeneous deposit on the filter substrate of the particle filter.

In a further advantageous embodiment of the method according to the invention, the pre-loading material flows through the particle filter together with a fluid, in particular air, as a result of a pressure difference applied across the filter, the fluid absorbing the particles from a deposited layer of the pre-loading material or the particles using a fluid Dispersing device are added. Both variants enable a uniform distribution of the pre-loading material in the dispersion and thus a homogeneous pre-loading of the filter substrate.

In a further advantageous embodiment of the method according to the invention, a pre-loading state of the particle filter is checked by weighing the particle filter and comparison with the mass of the filter determined before the pre-loading or by determining a differential pressure of the particle filter or by determining a mass flow, preferably a moisture content of the particles of the pre-loading material is taken into account.

The differential pressure or pressure drop across the particle filter and the mass flow are preferably related to one another via the flow resistance of the particle filter

Context.

In a further advantageous embodiment, a pre-loading state of the particle filter is checked by detecting a concentration of the pre-loading material on the outlet side of the filter, in particular behind the outlet of the filter

Measurements of these parameters before and after pre-loading allow conclusions to be drawn on the pre-loading state on the one hand and on possible damage to the particle filter on the other. By checking the pre-loading, the mass of pre-loading material can be corrected and the separation performance of the particle filter can be adjusted with high accuracy.

In a further advantageous embodiment of the invention, the pre-loading material is an oxide, in particular magnesium oxide, and / or a mineral, in particular

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Volcanic ash. These substances are particularly well suited for pre-loading because they have soot or ash-like properties and are easy to handle.

In a further advantageous embodiment of the method according to the invention, the particles of the pre-loading material are designed in such a way that they can be deposited by sorption on the effective surface of the filter substrate or in the pores thereof. In particular, absorption or adsorption on the filter substrate come into play here.

In a further advantageous embodiment of the method according to the invention, the pressure difference is increased in the course of an application of the particles in order to compensate for the increasing flow resistance of the particle filter during precharging and thus an increasing differential pressure with increasing precharging of the particle filter, in particular in such a way that the mass flow of the fluid remains at least substantially constant. This compensates for a reduced permeability of the filter with increasing pre-loading. In particular, the mass flow through the filter which is particularly suitable for homogeneous distribution of the particles on the filter substrate can be maintained.

Here, the method according to the invention takes advantage of an effect that the main flow, owing to the locally lower flow resistance, deviates in surface portions of the particle filter which have not yet been preloaded. Increasing the differential pressure means that these free surface portions of the filter substrate are better supplied with the particles of the pre-loading material, so that their permeability is also continuously reduced as a result. In this way, a particularly homogeneous distribution of the particles of the pre-loading material over the entire effective filter area of the particle filter is finally achieved. By preventing a significant drop in the mass flow, the particles of the pre-loading material also hit the filter substrate towards the end of the pre-loading with an impulse, which ensures a sufficiently stable attachment to the filter wall or the storage in its pores.

In a further advantageous embodiment of the method according to the invention, after or when the application of a predefined quantity has ended,

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in particular volume, mass or number of particles, a cleaning process of the end face on an inlet side of the particle filter, in which pre-loading material deposited there is removed. When the dispersion flows into the filter body, particles are deposited on the closures of the channels closed at the end face of the inlet of the filter body. It is advantageous to remove these deposits in order to prevent particles from trickling uncontrollably from this end face during further processing steps. This cleaning process is preferably carried out as soon as no more new particles are added, but the fluid is still flowing through the filter. In this way, the deposited particles can also still get into the particle filter, so that it is ensured that it is completely filled with the specified and appropriately metered amount of pre-loading material. The cleaning process can preferably be carried out mechanically, in particular by brushing, or also by targeted air flows, in particular by blowing off. Further options for the cleaning process are a targeted change of the flow with regard to direction and speed by running over the end face of the particle filter at a short distance with a suitably shaped screen.

In a further advantageous embodiment of the method according to the invention, the mass flow of the fluid is first generated through the filter and, as soon as it is stable, particles are dispersed in the fluid. This measure also increases the homogeneity of the distribution of the particles on the filter surface.

In a further advantageous embodiment of the method according to the invention, after or upon completion of the application of a predefined quantity, in particular volume, mass or number of particles or when a defined pre-loading of the particle filter has been achieved, no more particles are dispersed in the fluid and the mass flow, in particular after a cleaning process , maintained for a predefined period. In this way the binding of the particles

further improved in or on the filter substrate.

In a further advantageous embodiment of the method according to the invention, the flow through the particle filter is by means of a flap or a valve

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interrupted so that this flow can be switched on and off quickly while the fan is running continuously.

The features and advantages described above with regard to the first aspect of the invention also apply accordingly to the second aspect of the invention and vice versa.

In an advantageous embodiment of the device according to the invention, the particle filter can be arranged in the device in such a way that a main flow direction in the longitudinal direction of the mixing section is at least substantially perpendicular to an end face of the particle filter, in particular at least essentially parallel to channels of the particle filter. This results in a particularly homogeneous deposition of the particles of the pre-loading material on the filter surface.

In a further advantageous embodiment of the device according to the invention, the mixing section extends over a length in the longitudinal direction which is at least twice, preferably at least three times and most preferably at least five times as large as an, in particular average or maximum, expansion transverse to the longitudinal direction. In this way, a particularly good mixing of the fluid with the pre-loading material is achieved.

In a further advantageous embodiment of the device according to the invention, the mixing section has at least substantially the same cross section as the particle filter. This also results in a particularly homogeneous deposition of the particles of the pre-loading material on the filter surface.

In a further advantageous embodiment of the device according to the invention, it also has a pressure tank, in particular a vacuum tank, in which a pressure, in particular a vacuum, can be generated and / or maintained by means of the pump device, in particular a suction device. The pressure tank can cause fluctuations in the pressure difference between the inlet and outlet of the particle filter

be minimized. Preferably, residual amounts of the

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Particles of the pre-loading material are separated because the flow is almost there

comes to a standstill.

In a further advantageous embodiment of the device according to the invention, a fine filter can additionally be arranged in the flow direction behind the particle filter in order to filter out particles that have passed through the particle filter. This may be necessary to prevent these particles from getting into the environment (pollution, health protection). If sensors, in particular for mass flow measurement, are arranged in the flow direction behind the particle filter, the fine filter is preferably arranged in front of these sensors in order to prevent them from becoming dirty

protect.

In a further advantageous embodiment of the device according to the invention, it has a guide device for the fluid, in particular a blowing device and / or nozzles, designed to clean the end face on one side of the inlet of the particle filter by means of the fluid.

A guide device in the sense of the invention is preferably set up to influence the flow of the fluid in such a way that it cleans the surface, or is itself designed as a blowing device which is directed directly onto the surface.

In a further advantageous embodiment of the device according to the invention, the guide device has nozzles which define the blowing direction, the nozzles being arranged in such a way that the blown-out fluid strikes the end face obliquely.

In a further advantageous embodiment of the device according to the invention, the guide device has nozzles which define the blowing direction, the nozzles being arranged in such a way that a swirl is superimposed on the main flow of the fluid.

In a further advantageous embodiment of the device according to the invention, the guide device has or consists of a diaphragm which sweeps over the end face at a short distance, for example by rotation or translation, without touching it. The area on the one hand is reduced by the orifice, which leads to an increase in the flow velocity, in particular at the

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Edges of the bezel. On the other hand, the flow is deflected at the edges of the orifice plate, so that speed components occur parallel to the end face, which carry away the residual amounts of the pre-loading material deposited there and thus enable them to be sucked into the particle filter.

In a further advantageous embodiment of the device according to the invention, the projection of the diaphragm body of the diaphragm onto the end face results in a convexly enclosed area which spans the diameter of the end face completely or partially in one direction and only partially in the direction perpendicular thereto. A panel body, in particular a sheet metal strip, with a width of approximately 20% of the particle filter diameter is preferably used for this purpose, which is further preferably moved slowly over this end face at a distance of approximately 3 mm.

In a further advantageous embodiment of the device according to the invention, the dispersing device has a metering device which is set up to provide the amount of pre-loading material which is present in the filter during pre-loading

is to be brought in.

In a further advantageous embodiment of the device according to the invention, the dispersing device is designed as an ejector, in particular in the manner of a sandblasting gun.

In a further advantageous embodiment of the device according to the invention, a flow cross section for the fluid in the region of the dispersing device is reduced. In this way, a higher flow rate can be achieved, so that a higher static pressure and / or eddies arise, by means of which the mixing of the particles of the pre-loading material with the fluid is improved.

In a further advantageous embodiment of the device according to the invention, the particle filter is sealed by means of an inflatable sleeve during the pre-filling and / or cleaning in the device. This makes it possible to compensate for geometrical tolerances of the filter body and it can be ensured that there is no significant inflow or outflow that falsifies the set / measured mass flow or differential pressure or that preload material does not get into the particle filter

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In a further advantageous embodiment of the device according to the invention, sensors can be provided to detect boundary conditions such as mass flow, temperature, humidity or the like. to record and document or the process in

Controlling dependence on these measured values advantageously.

Further features and advantages result from the description of the figures. It

show at least partially schematically:

Figure 1 shows a first embodiment of a device for pre-loading a particle filter.

2 shows a second exemplary embodiment of a device for pre-loading a particle filter;

3 shows a third exemplary embodiment of a device for preloading a particle filter;

4 shows a fourth exemplary embodiment of a device for preloading a particle filter;

5 shows an exemplary embodiment of a method for preloading a particle filter;

6 shows a first exemplary embodiment of a guide device for the device for preloading a particle filter;

7 shows a second exemplary embodiment of a guide device for the device for preloading a particle filter;

8 shows a third exemplary embodiment of a guide device for the devices for preloading a particle filter; and

Fig. 9 shows a fourth embodiment of a guide device for the devices for preloading a particle filter.

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1 shows a first exemplary embodiment of a device for preloading a particle filter 4.

Fluid from an atmosphere, in particular ambient air, is sucked through the device by means of a pump device 6. The pumping power of the pump device 6 is regulated here, in particular via a sensor a for determining the static ambient pressure, a sensor b for determining a static negative pressure, and a sensor c1 or c2 for determining a throughput,

in particular a mass flow or volume flow.

The ambient air is preferably sucked in via a calming section 1 for calming the flow into a dispersing device 2 which is used for mixture preparation. A dispersion of the ambient air and the pre-loading material, which serves to pre-load the particle filter 4, is generated in particular in the dispersing device 2.

For this purpose, as shown in FIG. 1, the dispersing device 2 is preferably connected to a metering device 7. More preferably, the metering device 7 is a component of the dispersing device 2. The metering device 7 takes the pre-loading material from a silo 8 and feeds it in a defined amount into the dispersing device 2. The dosing device gives the pre-loading material

preferably directly in the mass flow of the fluid.

The dispersion produced is preferably sucked into the particle filter 4 via a mixing section 3.

The mixing section 3 is used for mixing, in particular for homogenization, of the dispersion, this means to produce the most uniform possible distribution of the particles in the fluid. The mixing section 3 extends over a length L in the longitudinal direction. The length L is advantageously at least twice, advantageously at least three times, particularly advantageously at least five times as large as the extent R transverse to the longitudinal direction. The longitudinal direction is preferably at an angle of at most 10 °, particularly preferably at most 5 °, most preferably parallel to a longitudinal axis of the channels of the particle filter 4. In the

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Mixing section 3 gives the dispersion a main flow direction, which advantageously runs essentially parallel to the longitudinal axis of the channels. It may be expedient to provide 3 flow guide elements 9 (not shown) in the cross section of the mixing section.

The cross section of the mixing section at the end facing the particle filter advantageously corresponds to the cross section of the end face 13 of the particle filter 4. In this way, the entire cross section of the particle filter 4, that is to say all the channels, is simultaneously subjected to dispersion. Dispersion is applied homogeneously to all channels by the upstream mixing section 3, so that a largely homogeneous distribution of pre-loading material finally results in all channels.

Due to the pressure difference, the dispersion is passed into or through the filter substrate. The dispersion preferably flows through those channels of the particle filter whose pores have not yet been sufficiently loaded with pre-loading material. As soon as the pores of a channel are sufficiently closed, there is no or no significant entry of pre-loading material. Excessive deposition of pre-loading material on the bottom of the channels is essentially avoided.

In this way, the pre-loading material is introduced into the channels as required, an excess of pre-loading material in the channels is largely avoided. Excess preloading material tends to fall out of the particle filter 4, moreover, it does not bring improved filter efficiency, so that the invention is advantageous both from an economic point of view and with regard to contamination by particles.

The bottom of the channel faces the opening of the channel. The filter surface of the channel, which has the pores, is formed on the circumference between the bottom and the opening. Excessive deposition means filling the channel with pre-loading material of more than 1/10, in particular 1/20, of the length of the channel, measured from the bottom of the channel.

Due to the deposit on the floor, the effective filter area of the channel becomes longer

reduced, so that deposits on the floor should preferably be minimized.

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In order to generate a uniform pressure difference with respect to the ambient pressure, the vacuum tank 5 which is preferably provided provides a volume in order to compensate for possible pressure fluctuations. Also, a flow essentially comes to a standstill in the vacuum tank 5, so that possible residual particles of the pre-loading material can be separated from the fluid before the fluid flows through the pump device 6 into the environment.

Downstream of the particle filter 4, a filter device (not shown) is preferably provided, which separates the particles of the pre-loading material that have passed through the filter surface of the particle filter from the air to be released into the environment.

A scale 10 serves, as described in relation to the method 100 according to the invention, to check the pre-loading of the particle filter 4.

The flow path of the fluid through the device is preferably sealed, in particular with respect to an applied pressure difference.

FIG. 2 shows a second exemplary embodiment of the device according to the invention for pre-loading a particle filter 4. The second exemplary embodiment differs from the first exemplary embodiment according to FIG. 1 essentially in that, instead of a negative pressure, the pump device 15 downstream of the particle filter 4 produces an excess pressure upstream of the particle filter 4 generated and the flow through the particle filter 4 is achieved. For this purpose, a blowing device 15 is arranged in front of the calming section 1.

3 shows a third exemplary embodiment of the device for pre-loading a particle filter 4.

This exemplary embodiment differs from the first and the second exemplary embodiment according to FIGS. 1 and 2 essentially in that the dispersing device 2 has a carrier plate 11. Instead of an application in a mass flow, the pre-loading material is 12 ° in this embodiment

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an optional mixing section 3 from a carrier plate 11 'directly into the filter 4

sucked.

Preloading material 12 is first applied to the carrier plate from the silo 8 by means of the metering device 7. The carrier plate 11 is then placed in front of an optional mixing section 3 or directly in front of that on the inlet side of the particle filter 4. This is indicated in FIG. 3 by the carrier plate 11 ° with the particles 12 '. From here, the particles 12 'are sucked into or through the filter 4 together with the ambient air sucked in. A further suction section 14 is preferably arranged between an optional vacuum tank 5 and the particle filter 4, in which

the mass or volume flow can be detected by means of a sensor c.

In this exemplary embodiment, the dispersion is thus generated by being sucked up from the carrier plate 11. In order to promote the complete suction of the pre-loading material, a relative movement between the carrier plate and the mixing section 3 and / or the particle filter 4 can preferably be provided.

4 shows a fourth exemplary embodiment of the device for pre-loading a particle filter 4.

In contrast to the third exemplary embodiment according to FIG. 3, the particles 12 ″ are sucked into the mixing section 3 via an intake section 1 before they enter the particle filter 4 together with the ambient air as a dispersion. The intake section 1 serves as a kind of elbow and creates turbulence in the flow, which leads to an improved production of the dispersion between the particles 12 ° and the ambient air. In order to ensure that the pre-loading material is completely sucked up, a relative movement between the carrier plate and the suction path can also be generated in this exemplary embodiment.

5 shows an exemplary embodiment of a method 100 according to the invention for pre-loading a particle filter 4.

In a first step 101, the pre-loading material is preferably conditioned. For this purpose, the pre-loading material is dried, tempered in particular

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and / or loosened to ensure a predefined humidity, a predefined temperature and / or the consistency required for further processing.

In a second work step 102 which follows the first work step directly or indirectly, a dispersion of the particles of the pre-loading material and a fluid, in particular a gaseous atmosphere, in particular air, is produced.

In the third and fourth exemplary embodiments of the device for pre-loading according to FIGS. 4 and 5, the dispersion is preferably produced by sucking up the pre-loading material 12 from a carrier plate 11.

In the first and the second exemplary embodiment of the device according to the invention according to FIGS. 2 and 3, the dispersion is preferably produced by introducing the pre-loading material into the fluid stream in a controlled manner. This can be done by direct feeding or blowing, possibly using a static pressure in the flow of the fluid. Alternatively, the dispersion is preferably produced by admixing a more highly concentrated dispersion, the

is generated mechanically or pneumatically in a suitable device.

In the third and fourth exemplary embodiments, the dispersion is produced by introducing a carrier device 11, 11 ° or a perforated plate or a carrier screen into the air flow, so that the pre-loading material 12, 12 ° is entrained by a flow. This can preferably be done by vibration of the carrier device

11.11 'are supported.

More preferably, in the first and second exemplary embodiments, an ejector is introduced into the air stream, with which the pre-loading material is mixed pneumatically (as in a sandblasting device) into the air stream.

More preferably, in the first and second exemplary embodiments, a container is introduced into the air stream, from which the pre-loading material is mechanically, for. B. by rotation of the container or a disc or pneumatically through air nozzles in or on the container, which blow out the pre-loading material, mixed into the air stream

becomes.

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In a third work step 103 which follows the second work step 102 directly or indirectly, the dispersion is introduced into the particle filter 4. The inlet side and the outlet side of the particle filter 4 are connected to one another in a fluid-communicating manner by the pores of the particle filter 4. In particular, the inlet side and the outlet side of the particle filter 4 are connected to one another exclusively by the filter substrate by means of the pores, so that it is ensured that the dispersion does not otherwise flow undefined between the inlet and outlet side. The dispersion at least partially separates into and / or on the effective filter surface. The particles of the pre-loading material are at least partially retained in and / or on the effective filter surface. The fluid reappears on the outlet side of the particle filter 4

out.

In the particle filter 4, the particles are deposited on the effective filter surface of the newly manufactured, i.e. H. filter substrate of the particle filter without soot loading,

or are stored in its pores.

The flow of fluid through the filter is preferably achieved by the device according to the invention generating a pressure difference between the inlet and the outlet of the particle filter 4. More preferably, the pressure difference is set in such a way that a main flow through the particle filter 4 corresponds at least essentially to the flow in real operation of the internal combustion engine. More preferably, the dispersion is flowed into the particle filter 4 until a desired degree of deposition of the particles in the particle filter 4 is reached. The desired degree of deposition preferably corresponds to a state in which the entire effective filter surface is homogeneously loaded with pre-loading material.

At least 90 percent, in particular 95 percent, in particular the entire cross section, of the inlet of the particle filter is preferably flowed with dispersion. At least 90 percent, in particular 95 percent, in particular the entire cross section, of the inlet of the particle filter are preferably used simultaneously with dispersion

flowed towards.

In a fourth work step 104, which follows the third work step 103 directly or indirectly or takes place in parallel, the pressure difference is in the course of a

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Spreading of the particles, in particular in the form of a dispersion before the inlet of the particle filter 4, is increased in order to compensate for a falling mass flow which occurs at the particle filter 4 with increasing preloading, which leads to an increasing flow resistance and thus differential pressure. The pressure difference is preferably increased so that the throughput of the fluid or the dispersion remains constant.

In a fifth work step 105a, which follows the fourth work step 104 directly or indirectly or takes place in parallel, the pre-loading state of the particle filter 4 is checked by weighing it and comparing it with the mass of the particle filter determined in the new state. A moisture content of the particles of the pre-loading material is preferably taken into account in order to be able to determine the exact amount of the embedded particles. Alternatively or additionally, the pre-loading state is checked by detecting a mass flow or throughput or the differential pressure before and after the pre-loading and / or the particle concentration behind the outlet of the particle filter 4, 105b.

The duration of a discharge of the pre-loading material is preferably set in such a way that the particle filter is loaded with a defined amount of pre-loading material after the method 100 has been completed. The defined amount is advantageously about 3 g to about 20 g dry weight per liter of filter volume, preferably about 10 g to about 15 g dry weight per liter of filter volume,

In a sixth working step 106, which follows the third working step 103 directly or indirectly or takes place in parallel, the end face 13 on the side of the inlet of the particle filter 4 is cleaned after and / or during the application of the particles by means of a cleaning process.

Since particle filters often consist of channels or tubes arranged parallel to one another, which are alternately closed at one end, there is generally an end face 13 on the inlet side of a particle filter 4, as is shown schematically in FIGS. 6, 7 and 8.

The dark squares each represent closed channels, the light squares open channels, with the representation both in terms of the exact shape

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the end face 13 and the cross-sectional areas of the channels is at least partially schematic.

The circumference of the channels forms the filter area. When the inlet side of the particle filter 4 flows in, the dispersion enters the open channels and from there passes via the filter surface to the outlet side of the particle filter 4, at least some of the particles of the pre-loading material adhering to and / or in the filter surface. When the end face 13 of the particle filter 4 flows against, particles of the pre-loading material are deposited in particular on the channels of the particle filter 4 which are closed on the end face 13.

These particles can be removed by a cleaning process in step 106 after and / or during the application of the particles and are preferably also thereby fed to the particle filter 4, so that they contribute to its pre-loading.

The cleaning process can be mechanical, e.g. B. by brushing, or by superimposing a swirl in the existing main flow of the fluid, or by blowing.

6 shows a specific cleaning process by means of a first exemplary embodiment of the guide device 9, which has nozzles which are oriented obliquely to the end face 13 of the particle filter 4. In this case, the guide device 9 is preferably a rotating T-tube, which is supplied with the fluid by means of a separate blowing device 15.

Alternatively, as shown in the second exemplary embodiment of a guide device in FIG. 7, the nozzles can be arranged on the circumference of a mixing section 3 adjacent to the end face 13 of the particle filter 4. The nozzles are preferably oriented obliquely, in particular at an angle of less than 60 °, in particular less than 45 °, to the end face 13 through which the fluid is blown in. If necessary, fluid can be applied to the nozzles one after the other and the process as often as desired

be repeated.

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In a third exemplary embodiment of the steering device, the fluid, as shown in FIG. 8, can be inclined via non-radially arranged nozzles on the circumference of the mixing section 3 adjacent to the end face 13 of the particle filter 4, in particular at an angle of less than 60 °, in particular less than 45 °, or be blown in parallel to the end face 13. Here, too, it is preferably possible to blow in through all the nozzles simultaneously or in succession. Furthermore, the blowing direction B can be directed directly onto the end face 13 or in such a way that a swirl component is generated in a main flow of the fluid oriented essentially perpendicular to the end face 13 or is superimposed on this main flow. The main flow here is preferably that flow which follows the essentially predominant flow direction.

The third exemplary embodiment of the steering device in FIG. 8 can advantageously also be used during the third working step 103, i.e. if pre-loading material is still being transported with the main flow. This can

Deposits on the closed channels are reduced from the outset.

In a fourth exemplary embodiment, as shown in FIG. 9, the steering device has a diaphragm 9 which spans the diameter of the end face completely or partially in one direction and only partially in the direction perpendicular thereto. For this purpose, an orifice body with a width of approximately 20% of the particle filter diameter is preferably used, which is slowly moved over this end face at a short distance, the flow being accelerated in particular at the edges of the orifice and deflected such that residual amounts of the pre-loading material on the Face are sucked into the particle filter. This advantageously takes place during the third work step 103.

The second and third exemplary embodiments of the guide device can also be implemented in a device according to the second exemplary embodiment (FIG. 2), third exemplary embodiment (FIG. 3) or fourth exemplary embodiment (FIG. 4) without an additional fan for the nozzles. For this purpose, the nozzle is preferably arranged within the mixing section 3 and the main flow is used to supply the nozzles. by keeping the same

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local pressure, the main flow is reduced by increasing the flow resistance in the mixing section 3 upstream of the particle filter 4.

100 parameters such as differential pressure and mass flow are preferably recorded during the method. In particular, at least one of these measured values is processed further in order to monitor the state of the particle filter 4, in particular with regard to filter damage.

The pressure difference is preferably selected such that a mass flow of the fluid of greater than about 200 kg, preferably greater than about 300 kg and most preferably greater than about 400 kg per hour and per liter of filter volume of the particle filter 4 flows through.

The particles of the preloading material are furthermore preferably distinguished by a high tendency to adhere to surfaces. Method 100 is preferably carried out at 19 ° C. to 21 ° C., in particular at 20 ° C. As a result, the particles adhere particularly well to surfaces.

It should be pointed out that the exemplary embodiments are merely examples which are not intended to restrict the scope of protection, the applications and the structure in any way. Rather, the person skilled in the art is given a guideline for the implementation of at least one exemplary embodiment by the preceding description, it being possible for various changes, in particular with regard to the function and arrangement of the described components, to be carried out without leaving the scope of protection, as is evident from the claims and gives these equivalent combinations of features. In particular, the sequence of the work steps of the method 100 can be varied and the individual features of the exemplary embodiments of the device can be combined with one another. The device variants shown schematically in the figures also take into account the possibility of automation, in which the particle filter is fed to the device manually or by another suitable device at defined transfer points, for example directly onto the scale, and is also removed again. In addition to the dosage of the pre-loading material, which is stored in a storage silo as shown,

Then the transport within the device between the transfer point, the scales and the pre-loading position takes place automatically.

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List of reference symbols for calming section 1 dispersing device 2 mixing section 3

Particle filter 4 Pressure tank 5 Suction device 6 Dosing device 7

Silo 8 guide device 9 scale 10 carrier device 11, 11 'pre-loading material 12, 12'

End face of the particle

filters on the inlet side 13 suction section 14 blowing device 15 sensor for determining the static ambient pressure a sensor for determining a static underpressure or overpressure pressure

Sensor for determining a

Flow rate C blowing direction B length L expansion R

PT32289AT

Claims (1)

15 20 25th 30th - 25 AVL Tippelmann GmbH PT32289AT Claims 1. Method (100) for pre-loading a particle filter (4), in particular an internal combustion engine, in which particles of a pre-loading material in a dispersion together with a fluid, in particular air, by means of a pressure difference between the inlet and outlet of the particle filter (4) in the particle filter ( 4) are introduced (103), the pressure difference being selected in such a way that a mass flow of the fluid of greater than about 200 kg, preferably greater than about 300 kg and most preferably greater than about 400 kg per hour and per liter of filter volume flowed through of the particle filter (4). 2, Method (100) according to claim 1, wherein a main flow direction through the particle filter corresponds at least substantially to the flow direction in real operation of the internal combustion engine. 3. The method (100) according to claim 1 or 2, wherein the preloading material is preconditioned, in particular dried, tempered and / or loosened, so that it has a predefined moisture content, a predefined temperature and / or the consistency required for further processing (101 ). 4. The method (100) according to any one of the preceding claims 1 to 3, wherein the dispersion is generated by the fluid taking up the particles of the pre-loading material from a deposited layer 12, 12 'of the particles or by mixing the particles into the fluid (102). 5. The method (100) according to any one of the preceding claims 1 to 4, wherein a pre-loading state of the particle filter (4) by weighing the particle filter (4) and comparison with the mass of the filter (4) determined before the pre-loading or by determining a differential pressure of the Particulate filter (4) or by determining a mass flow is checked, preferably one Moisture of the particles of the pre-loading material is taken into account (1063). 15 20 25th 30th -26- AVL Tippelmann GmbH PT32289AT 10th 11. Method (100) according to one of the preceding claims 1 to 5, wherein a pre-loading state of the particle filter (4) is checked (106b) by detecting a concentration of the pre-loading material on the outlet side of the filter, in particular behind the outlet of the filter. Method (100) according to one of the preceding claims 1 to 6, wherein the pressure difference is increased (105) in the course of an application of the particles in order to compensate for an increasing differential pressure of the particle filter (4) with increasing preloading of the particle filter (4), in particular in the Way that the mass flow of the fluid remains at least substantially constant. Method (100) according to one of the preceding claims 1 to 7, wherein after or upon completion of the application of a predefined quantity, in particular volume, mass or number of particles, a cleaning process of the end face (13) follows on an inlet side of the particle filter (4) (107), in which pre-loading material deposited there is removed. Method (100) according to one of the preceding claims 1 to 8, wherein first the mass flow of the fluid through the filter (4) is generated and, as soon as it is stable, particles are dispersed in the fluid. Method (100) according to one of the preceding claims 1 to 9, wherein after or upon completion of the application of a predefined amount, in particular volume, mass or number of particles or when a defined pre-loading of the particle filter (4) no longer disperses particles in the fluid and the mass flow, especially after a cleaning process, is maintained over a predefined period. Device for preloading a particle filter (4), in particular an internal combustion engine, preferably by means of a method according to one of claims 1 to 10 a dispersing device (2), which is set up to particles of a pre-loading material in a fluid to produce a dispersion disperse, 15 20 25th 30th "27 - AVL Tippelmann GmbH PT32289AT 12th 13. 14. 15. 16. 17th a pump device (6, 15) to generate a pressure difference between the inlet side and outlet side of the particle filter (4), and a mixing section (3) which is arranged downstream of the dispersing device (2) and with an inlet of the particle filter (4) is fluidly connectable. Device according to claim 11, wherein the particle filter (4) can be arranged in the device in such a way that a main flow direction in the longitudinal direction of the mixing section is at least substantially perpendicular to an end face (13) of the particle filter (4), in particular at least substantially parallel to channels of the particle filter (4) is aligned. Apparatus according to claim 11 or 12, wherein the intermixing section (3) extends over a length (L) in the longitudinal direction which is at least twice, preferably at least three times and most preferably at least five times as large as an, in particular medium or maximum, extension (R ) across Longitudinal direction. Device according to one of claims 11 to 13, wherein the mixing section (3) has at least substantially the same cross section as the particle filter (4). Device according to one of claims 11 to 14, further comprising a pressure tank (5) in which a pressure can be generated and / or maintained by means of the pump device (6). Device according to one of claims 11 to 15, wherein the dispersing device (2) comprises a metering device (8), which is set up to the for the To provide the pre-loading required amount of the pre-loading material. Device according to one of claims 11 to 16, wherein a flow cross section in the region of the dispersing device (2) is reduced. 18. Pre-loaded particle filter (4), in particular pre-loading by means of a method (100) according to one of claims 1 to 10, with channels which extend from an opening on an end face (13) of an inlet side of the particle filter (4) into the particle filter (4 ) extend into and are each closed by a bottom, which is opposite the opening, the channels, on average or all, starting from the bottom to less than 1/10, in particular 1/20, of the length of the channels from the opening to Bottom filled with pre-loading material.