DE10321033A1 - Catalyst converter for emission purifier used in motor vehicle, has converter body with channels whose inner and outer surfaces have different coatings to trigger different catalytic effects when exhaust gas passes through channels - Google Patents

Abstract

The converter (1) has a converter body (2) with parallel channels (2.1). Exhaust gas flows through the channels, through a particle filter (8), and then around the channels in the opposite direction. Different coatings are applied on the inner surface (2.2) and outer surface (2.3) of each channel to trigger different catalytic effects when the exhaust gas passes through the channels. The channels are arranged parallel to each other at predetermined intervals, such that two exhaust gas flows can pass through the channels in different directions at the same time.

Description

The The invention relates to a catalyst for an exhaust gas purification device of a motor vehicle with a parallel arrangement, an inner surface having channels formed body, the channels each one with respect to a plane first flow cross-section form, which a first flow direction assigned.

It is already a filter assembly as an exhaust gas purification device for the separation of particles from the exhaust gas from the DE 100 36 597 known. The filter assembly comprises a housing in which between a lower inlet chamber and an upper outlet chamber in a flow path at least one porous filter body is provided, which is provided with means for triggering the combustion of soot deposits. Further, the inlet housing is associated with an ash collection chamber, which is provided with respect to the exhaust gas flow in the inlet fan with a particle-permeable cover.

Of the Invention is based on the object, an exhaust gas purification device such form and arrange that the exhaust gas mechanically and twice is chemically cleaned and the ratio of that per unit time cleaned exhaust gas volume is optimized to the size of the housing.

Is solved the task according to the invention by that the channels at least partially spaced from each other and with Reference to a second level between the individual channels at least form a second flow cross section, which is flowed through in a second flow direction. This ensures that the body of the catalyst in two, allowing dry cleaning flow directions flows through can be. As a result, two independent flow cross sections are in a body formed and available standing surfaces are used optimally. Thus, the size can be reduced to a minimum become.

Regarding In a special embodiment, it is advantageous that the channels in the body in such a way are arranged that the body flows through in a cross-counterflow becomes. By this vertical orientation of the two exhaust gas streams is a special flow arrangement created, which is an optimal use of the catalytic effect to disposal standing surfaces allowed.

A additional possibility is according to a further development, that the inner surface of the channel a coating B1 with a first catalytic property and the outer surface of the Channels a coating B2 with one of the coating B1 of palm of the channel different or equal catalytic property having. The coating B1 is the first flow direction and the coating B2 associated with the second flow direction. Thereby the catalyst has bifunctional properties, which in terms of the exhaust gas treatment or purification are beneficial.

In In this context, it is advantageous that the first coating B1 an oxidizing effect and the second coating B2 a the exhaust gas has de-stiffening effect. This will be a qualitative improved exhaust gas treatment and cleaning achieved. After the oxidizing Treatment, the exhaust gas is filtered before it is used for denitrification a second time between the channels through the body flows.

In further context, it is advantageous that the body in an exhaust gas purification device is provided. The exhaust gas purification device forms a special type of catalyst and has a housing with an inlet pipe and an outlet pipe and arranged in the housing Particle filter on. The combination of a mechanical filter element with a catalyst allows due to the bifunctionality of the body a small size and a optimal exhaust gas treatment.

According to one preferred embodiment of inventive solution in the end provided that the housing has four chambers arranged one behind the other, the inlet pipe in the second chamber, in the body is arranged, the particle filter arranged in the fourth chamber and the exit tube from the first chamber through the second, third and fourth chamber or out directly from the housing out. This is the possibility created that the exhaust gas flows through the body first, then flows through the particulate filter and in a second flow direction the second flow cross section of the body is directed.

From special meaning is for the present invention that an exhaust gas flow in substantially vertical and horizontal flow direction through the body and conductive in a substantially vertical flow direction through the particulate filter is. Due to the vertical orientation of the first through-flow channels of the body and of the particulate filter, the particles fall due to gravity down in one to the housing subsequent Lower shell in which they are collected. The through the particle filter Purified exhaust gas flow can be without the risk of larger deposits in horizontal flow direction passed through the body become.

in the Connection with the construction and arrangement according to the invention it is advantageous that a hot air blower generating a hot air flow is provided is and the hot air flow over one Valve control in the housing is blown, wherein the valve control comprises a pressure element, the to the pressure conditions in the case is adapted and a blowing during the operation of the internal combustion engine allows. This allows the particulate filter during operation of the internal combustion engine getting cleaned. The hot air stream is automatically conveyed with the exhaust gas flow into the particulate filter.

Advantageous it is further provided that a vibration unit on the housing is and the case over at least two rubber bearings stored directly or indirectly on the motor vehicle is. Thereby, the generated by the vibration unit and in the case guided impulses are not damped by the vehicle frame. Of the Efficiency of the vibration unit based on the shaken soot or Amount of ash is thereby improved.

Besides that is It is beneficial that as a body monolithic honeycomb body is provided, which is extruded from a catalytic material and coated molding or formed from a coated with catalytic material ceramic body is. The ceramic body is coated differently in terms of bifunctionality. The channels are coated in with a different catalytic material than outside. In a molded article of catalytic material, is this to achieve the Bifunktionalität partially with a material coated, which has a different catalytic property, than that of the molding itself. Preference is given to the channels from the outside additionally coated.

Further Advantages and details of the invention are in the claims and explained in the description and shown in the figures.

there demonstrate:

1 a schematic side view of an exhaust gas purification device with inlet pipe and vertically traversed channels;

2 one opposite 1 rotated 180 ° schematic side view of an exhaust gas purification device with output tube and horizontally flowed channels;

3 a three-dimensional sectional view of an exhaust gas purification device with the course of the exhaust stream.

As in the 1 and 3 shown, the exhaust gas flows through an inlet pipe 7.1 in a housing 9 the exhaust gas purification device 7 , The housing 9 is through two end walls 17 . 18 bounded in the horizontal direction and by means of partitions 14 . 15 . 16 in four, arranged in a horizontal direction one behind the other chambers 9.1 to 9.4 divided. At the bottom is the case 9 in the area of the second 9.2 and fourth chamber 9.4 open. By one below the housing 9 arranged lower shell 9.5 is the case 9 sealed.

The exhaust gas is through the inlet pipe 7.1 through the first chamber 9.1 passed through and flows into the second chamber 9.2 in which a body 2 as a catalyst 1 is arranged. The exhaust gas flows from above in a vertical direction through the body 2 through and then through an exhaust baffle 11 90 ° to the horizontal. For this purpose, the exhaust baffle 11 between the body 2 and the lower shell 9.5 arranged.

The exhaust stream thread 10 flows in a horizontal direction at the third chamber 9.3 over and through the inclined formed lower shell 9.5 again in the vertical direction through the particle filter 8th passed in the fourth chamber 9.4 is arranged. After flowing through the particle filter 8th becomes the exhaust gas flow 10 according to the 2 and 3 via openings in the partitions 14 . 15 . 16 in the opposite direction towards the first chamber 9.1 through the housing 9 directed.

For this purpose, the circulation through the third chamber 9.3 further developed from the exhaust stream 10 in a horizontal direction between the channels 2.1 enters and the body 2 flows through in a horizontal direction. Via openings in the partition 14 flows the exhaust stream 10 in the second chamber 9.2 , From there, the exhaust gas flow 10 over the exit pipe 7.2 directed to the atmosphere. In the exit pipe 7.2 flows through the exhaust stream 10 a third time the case 9 in a horizontal direction.

In 3 is in particular the course of the manifold branching exhaust stream 10 within the exhaust gas purification device 7 shown.

The housing 9 is by means of partitions 14 . 15 . 16 in the four chambers 9.1 . 9.2 . 9.3 . 9.4 divided and closes by the end walls 17 . 18 in a horizontal direction. The openings have identical diameter in this embodiment, which is advantageous in terms of manufacturing. Depending on the configuration and flow conditions, the openings have different diameters.

The first chamber 9.1 is in a horizontal direction through the front wall 17 and the partition 14 limited. The front wall 17 and the partition 14 have an opening 17a and 14a for the inlet pipe 7.1 on. The exhaust gas flow 10 flows through the inlet pipe 7.1 in the second chamber 9.2 and spread on the lid 2.4 of the body 2 and branches in the vertical direction in the fifteen coated channels 2.1 ,

After the deflection through the exhaust baffle 11 the recombined exhaust stream flows 10 in the horizontal direction partially along the lower shell 9.5 to the fourth chamber 9.4 in the particle filter 8th into it. In the particle filter 8th Branches the exhaust stream 10 into numerous sub-streams to after the particulate filter 8th again uniform through the opening 16a the partition 16 in the third chamber 9.3 to stream.

The exhaust gas flows out of the particle filter 8th out and funnel-shaped through the opening 16a in the third chamber 9.3 directed. In the third chamber 9.3 becomes the exhaust gas flow 10 directed in the vertical direction downwards and flows through three juxtaposed openings in the horizontal direction in the second chamber 9.2 in which he divides into six streams. The openings 15b and 15d are in the 1 to 3 shown. The opening 15c is through an exhaust stream 10 indicated.

After the horizontal flow through the body 2 the exhaust gas flows back into three partial streams through three openings 14b . 14c . 14d through the partition 14 in the first chamber 9.1 and collects at an opening 14e back to a streamline. At the opening 14e closes the exit pipe 7.2 on that the exhaust gas flow 10 through the second 9.2 third 9.3 and fourth chamber 9.4 through the case 9 leads out. For this purpose, have the partitions 14 . 15 . 16 one opening each 14e . 15a . 16b and the front wall 18 an opening 18a on.

As in the 1 to 3 represented, the body becomes 2 in the vertical flow direction 5 and in the horizontal flow direction 6 flows through and is made of three mutually parallel rows of five channels 2.1 educated.

The channels 2.1 pointing in the direction of flow 5 , perpendicular to a plane E1, an inner flow cross-section 3 on. The sum of all flow cross sections 3 forms the total cross section of the body 2 for conducting the exhaust gas in the vertical direction. The inner surface 2.2 of the channels 2.1 have a coating with catalytic property, whereby parts of the exhaust gas, mainly monoxide compounds such as nitrogen and carbon monoxide are oxidized.

The channels 2.1 are to each other with a distance 4 arranged so that the exhaust gas flow 10 as in 2 and 3 also shown in the horizontal flow direction 6 through the body 2 flows. By the distances 4 becomes with respect to a plane E2 in the flow direction 6 a corresponding flow cross section is formed.

To the two in the vertical and horizontal direction led exhaust gas flows 10 to separate from each other are the channels 2.1 each with their end faces in a lid 2.4 and in a ground 2.5 integrated. The exhaust gas flow in the horizontal direction 10 is thus between the lid 2.4 and the floor 2.5 between the channels 2.1 passed. The outer surface 2.3 of the channels 2.1 has a catalytic property coating to de-grease the exhaust gas. Thus, the body rejects 2 in terms of its property as a catalyst 1 bifunctional properties.

As in 3 shown are the openings 14b . 14c . 14d in flight to the openings 15b . 15c . 15d aligned. The exhaust gas is through the three adjacent openings 15b . 15c . 15d for each series of channels 2.1 separately in the second chamber 9.2 introduced and flows around each channel 2.1 over its entire length and its entire circumference. In one embodiment, not shown, there are more than three openings in the partitions 14 . 15 . 16 provided to the the efficiency and the flow conditions when order flow around the channels 2.1 to optimize in a horizontal direction.

In 2 is a vibration unit 13 shown on the housing 9 is attached. The vibration unit 13 transmits vibrations to the housing 9 and the particulate filter 8th to dissolve the burnup and soot particles that collect at the lowest point in the lower shell due to gravity. There, the particles fall into a collection container 13.3 which can be removed for emptying.

Because of the case 9 over two rubber mounts 13.1 . 13.2 at the frame 19 of the motor vehicle are stored by the vibration unit 13 introduced pulses only slightly damped over the vehicle frame. This will increase the efficiency of the vibration unit 13 significantly increased.

Further, as in the 2 and 3 shown a hot air blower 12 provided, the hot air into the housing 9 and in the particle filter 8th blows. To ensure the injection of hot air during operation of the motor vehicle, a valve 12.3 via a valve control 12.1 with a spring 12.2 controlled. Depending on the pressure conditions in the housing 9 opens the valve 12.3 with a corresponding overpressure of the hot air. The hot air is combined with the existing exhaust gas flow 10 in the particle filter 8th geför dert and thus formed the burnup.

Claims (10)

Catalyst ( 1 ) for an exhaust gas purification device ( 7 ) of a motor vehicle with an arranged parallel to each other, an inner surface ( 2.2 ) having channels ( 2.1 ) formed body ( 2 ), whereby the channels ( 2.1 ) in each case one with respect to a plane (E1) first flow cross-section ( 3 ), to which a first flow direction ( 5 ), characterized in that the channels ( 2.1 ) at least partially to each other by far ( 4 ) and with respect to a second plane (E2) between the individual channels ( 2.1 ) form at least a second flow cross-section, which in a second flow direction ( 6 ) is flowed through. Catalyst ( 1 ) according to claim 1, characterized in that the channels ( 2.1 ) in the body ( 2 ) are arranged such that the body ( 2 ) is flowed through in cross-counterflow. Catalyst ( 1 ) according to claim 1 or 2, characterized in that the inner surface ( 2.2 ) of the channel ( 2.1 ) has a coating B1 with a first catalytic property and the outer surface ( 2.3 ) of the channel ( 2.1 ) a coating B2 with one of the coating B1 of the inner surface ( 2.2 ) of the channel ( 2.1 ) has different or the same catalytic property. Catalyst ( 1 ) according to one of the preceding claims, characterized in that the first coating B1 has an oxidizing effect and the second coating B2 has an effect of de-stiffening the exhaust gas. Catalyst ( 1 ) according to one of the preceding claims, characterized in that the body ( 2 ) in an exhaust gas purification device ( 7 ) is provided and the exhaust gas purification device ( 7 ) a housing ( 9 ) with an inlet pipe ( 7.1 ) and a starting tube ( 7.2 ) as well as one in the housing ( 9 ) arranged particulate filter ( 8th ) having. Catalyst ( 1 ) according to one of the preceding claims, characterized in that the housing ( 9 ) four chambers arranged one behind the other ( 9.1 - 9.4 ), the inlet pipe ( 7.1 ) in the second chamber ( 9.2 ), in which the body ( 2 ), the particulate filter ( 8th ) in the fourth chamber ( 9.4 ) and the output tube ( 7.2 ) from the first chamber ( 9.1 ) through the second ( 9.2 ), third ( 9.3 ) and fourth chamber ( 9.4 ) or directly from the housing ( 9 ) is led out. Catalyst ( 1 ) according to one of the preceding claims, characterized in that an exhaust gas flow thread ( 10 ) in a substantially vertical and horizontal flow direction through the body ( 2 ) and in a substantially vertical flow direction through the particulate filter ( 8th ) is conductive. Catalyst ( 1 ) according to one of the preceding claims, characterized in that a hot air flow generating hot air blower ( 12 ) is provided and the hot air flow via a valve control ( 12.1 ) in the housing ( 9 ) is blown, wherein the valve control ( 12.1 ) an overpressure element ( 12.2 ), which corresponds to the pressure conditions in the housing ( 9 ) is adapted and allows blowing during operation of the internal combustion engine. Catalyst ( 1 ) according to one of the preceding claims, characterized in that a vibration unit ( 13 ) on the housing ( 9 ) is provided and the housing ( 9 ) via at least two rubber mounts ( 13.1 . 13.2 ) is mounted directly or indirectly on the motor vehicle. Catalyst ( 1 ) according to one of the preceding claims, characterized in that as body ( 2 ) is provided a monolithic honeycomb body, which is formed from a molded article of catalytic material or from a catalytic material coated ceramic body.